Sagittal cross section of the tooth

A publication of the Micro and Nanoelectrotechnologies Department of

National Institute for Research and Development in Electrical Engineering ICPE - Advanced Research (INCDIE ICPE-CA)

Bulletin of Micro and Nanoelectrotechnologies

December 2015, vol. VII, no.3-4

Editorial Board Scientific Staff

• Alexandru Aldea - NIMP, Bucharest, Romania • Robert Allen, University of Southampton • Leonardo G. Andrade e Silva - Institute for Nuclear Energy Research, Av. Prof. Lineu Prestes,

São Paulo, Brazil • Ioan Ardelean - Academy Romanian Institute of Biology, Bucharest, Romania • Marius Bâzu - IMT Bucharest, Romania • Constantin Brezeanu - Faculty of Electronic, Politehnica University, Bucharest • Maria Cazacu – Academy Romanian Institute Petru Poni of Macromolecular Chemistry, Iasi,

Romania • Mircea Chipară - The University of Texas Pan American, Physics and Geology Department,

USA • Sorin Coţofană - The Deft University, The Netherland • Olgun Güven - Hacettepe University, Department of Chemistry, Polymer Chemistry Division,

Ankara, Turkey • Elena Hamciuc – Academy Romanian Institute Petru Poni of Macromolecular Chemistry, Iasi,

Romania • Wilhelm Kappel - INCDIE ICPE - CA, Bucharest, Romania • Yoshihito Osada, Hokkaido University, Riken Advanced Science Institute, Japan • Mircea Rădulescu - Universitatea Tehnica din Cluj-Napoca, Romania • Yoshiro Tajitsu, Kansai University, Japan • Cristian Teodorescu - NIMP, Bucharest, Romania • Elena Trif – Romanian Academy Institute of Biochemistry, Bucharest, Romania • Traian Zaharescu – INCDIE ICPE - CA, Bucharest, Romania • Slawomir Wiak - Technical University of Lodz, Poland

Executive Staff

• Cristian Morari, INCDIE ICPE – CA, Bucharest, Romania • Gabriela Obreja, INCDIE ICPE – CA, Bucharest, Romania • Iulia Tănase, INCDIE ICPE – CA, Bucharest, Romania • Gabriela Iosif, INCDIE ICPE – CA, Bucharest, Romania

Editor in chief

• Mircea Ignat - INCDIE ICPE - CA, Dep. MNE, mircea.ignat@icpe-ca.ro

ISSN 2069-1505

Manuscript submission The Guest Editors will send the manuscripts by post or to the e-mail: mircea.ignat@icpe-ca.ro Address: Splaiul Unirii No. 313, sect. 3, Bucharest-030138 - Romania

Our staff will contact the Guest Editors in order to arrange future actions concerning manuscripts

Bulletin of Micro and Nanoelectrotechnologies includes the specific research

studies on:

• Microelectromechanical and nanoelectromechanical components. • The typical micro and nanostructure of actuators, micromotors and sensors. • The harvesting microsystems. • The conventional and unconventional technologies on MEMS and NEMS. • The theoretical and experimental studies on electric, magnetic or electromagnetic

field with applications on micro and nano actuating and sensing effects. • The design algorithms or procedures of MEMS and NEMS components. • The applications of MEMS and NEMS in biology and in biomedical field. • The new materials in MEMS and NEMS. • The standardization and reliability preoccupations. • The economic and financial analysis and evolutions of MEMS and NEMS

specific markets.

CHRONICLE

The 3-4/2015 number of Bulletin is dedicated to the XVI INGIMED

workshop, November 26, unfolded to headquarters of the National Institute

for Research and Development in Electrical Engineering-Advanced Research

(to see some images of this scientific event).

We remember the main participants to the XVI INGIMED edition:

Prof. Vitalie Scripnic (guest of Chisinau), Prof. Dr. Constantin Bogdan,

Prof. Mircea Ifrim, Prof. Dr. Eng. Andrei Marinescu, Prof. Dr. Eng. Radu

Negoescu , Prof. Dr. Eng. Ciprian Racuciu, Physician Corina Cîrdei.

This BMNE number includes 6 papers (of 12 papers to INGIMED

which were presented to the XVI INGIMED workshop), with the

participation of the three teams of the Alexandru Proca Centre of Scientific

Research Initiation of the Young, and an interesting paper: Autonomous

Landmine Detection Robot which belongs to Matei Sarivan who is a student at

Robotics Division of Aalborg University.

Editor in Chief

Mircea Ignat

The XVI INGIMED workshop– images

Contents

Reviews Ioan I. Ardelean………………………...………………………………………………….. 11 In Memoriam POMPILIU MANEA: 40 Years of Medical Engineering in Transylvania Prof. Dr. Constantin Bogdan ………...……………………………………...…………….. 15 Biomedical Engineering 2015: Quo Vadis Europe? Radu Negoescu ……………………….…………………………………………………… 19 Comparative Analysis of Cone Beam 3D Medical and Industrial Maria Corina Cîrcei, Ciprian Răcuciu, Ion Tiseanu, Adrian Sima ..……………………… 25 Current State and WiTricity Technology Application Perspectives for Implantable Medical Devices Andrei Marinescu, Mihai Tarata, Mihai Iordache …………………………..…………...... 45 Devices for medical rehabilitation Ana Cosma Radu, Mosessohn Vlad, Mihaila Alin …….………………………………….. 51 Autonomous Landmine Detection Robot Ioan-Matei Sarivan ………………………………………………………………………... 57 Eye anatomy and movement Andra-Maria Ciutac, Carmen Gabriela Popa ……………………………………………… 67

Preparation of a Formatted Technical Paper for the Bulletin of Micro and Nanoelectrotechnologies Clara Hender, Cristian Morari……………………………………………………………………. 75

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Cyanobacteria for Bioremediation of Wastewaters, 2016. Inga Z., Cepoi L. (eds) Springer International Publishing, ISBN 978-3-319-26749-4, 124 p.

The book ”Cyanobacteria for Bioremediation of Wastewaters”deals with a very interesting and modern topic: the importance of cyanobacteria, oxygenic photosynthetic prokaryotes, for the bioremediation of wastewater, with special emphasis on removal of organic pollutants and metals from wastewater. After a short introductory chapter, the next two chapters clearly review the topics of water quality and conventional methods of wastewater treatment, respectively.The fourth chapter shows the most important results (in the laboratory as well as in real life, outdoor experiments ) obtained by the authors with respect to the removal of organic pollutants from wastewater by cyanobacteria, smoothly integrated in some of the results reported on the same topic in the literature. The larger chapter of this book concerns metals removal by cyanobacteria, copiously reflecting the rich personal scientific experience of the contributors on this topic. In strong correlation with this topic, the last chapter focuss on the biosynthesis of metal nanoparticles by cyanobacteria as one of the mechanisms involved in the bioremediation of metals. The book ends with an useful index. Each chapter has a reach reference list whereas the illustration is very unbalanced from one chapter to another: the majority of the chapters hase no illustration at all, whereas thelarger chapter has 6 tables and 29 figures, each one rich in scientific information. The book is edited by two well known specialists in the field of cyanobacterial biotechnology who also copiously contributed to the 7 chapters of this book, joing their coworkers from both Russia and Republic of Moldova. In my opinion the book „Cyanobacteria for Bioremediation of Wastewaters” is a valuable reading for undergraduated students as well as for already known scientists working in the field of bio(nano) technology, and managers. Prof. Ioan I. Ardelean

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Algal Biorefineries: Volume 2: Products and Refinery Design, 2015. Prokop A., Bajpai R., and Zappi M., (eds). Springer International Publishing, ISBN 978-3-319-20199-3, 557 p, 54 illus., 78 in colour.

The book „Algal Biorefineries: Volume 2: Products and Refinery Design” is structured by the editors in two parts. Part I „Algal growth, products and optimization microalgal systems biology for biofuel production”contains several chapters focusing on systems biology, especially metabolic reconstruction for algal biofuel production, government regulation of the uses of genetically modified algae (and other microorganisms) in biofuel and bio-based chemical productionas well as on the advantages and limitation concerning heterotrophic and mixotrophic growth of microalgae; special attention is focussed on different ways to grow microalgae (closed photobioreactors, tubular photobioreactors, photobioreactors with internal illumination, flat panels and sloping cascades).The chapters concerning growing media, in this volume, focus on gas balances and the importance of oligoelements (selenium, rare earth elements) for algal growth and biorefinery. In part II “Biorefinery design and processing steps” one chapter reviews different available technologies to extract lipids either from intact cell or from previously disrupted cells by different methods, including hydrothermal pretreatments. Conversion of microalgae bio-oil into bio-diesel is also clearly presented as well as the conversion of algal biomass to methane and molecular hydrogen. Special attention is also devoted to the valorification of byproducts resulted after lipid extraction, so called algal wastes, to obtain different products (feed, glues etc) which can be commercialized to contribute to the economical sustainability of biodiesel production from microalgae. The last two chapters of this book deal with true economic analysis of the potential for large scale utilization of algal biodiesel, as example, in U.S. Airline Industry. The contributors are well known scientists in their field under the leading authority of truly famous scientists acting as Editors. The chapters are written very clearly, having a very generous bibliography and useful illustrations. This second volume of the Series increases the interest of the reader (undergraduate student, known scientist, science policy managers, entrepreneurs) for the volumes to come. Prof. Ioan I. Ardelean

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Biomass and Biofuels from Microalgae: Advances in Engineering and Biology. Moheimani, N.R., McHenry, M.P., de Boer, K., Bahri, P. (Eds.), Springer International AG Switzerland ISBN 978-3-319-16639-1 2015, 373 p, 42 illus., 27 illus in color.

The book „Biomass and Biofuels from Microalgae: Advances in Engineering and Biology” is the second volume of the Series Biofuels and Biorefineries Technologies. The first chapter is an excellent introduction in the topic of the book, smoothly introducing the reader, even an undergraduate student, without boring the already advised scientist. The other 16 chapters deals with essential biological, technical and economic items concerning the large-scale production of biomass and biofuels from microalgae, the significance and practical importance (with examples of large scale applications) concerning: immobilization techniques, the use of heterotrophic metabolism for biodiesel oil production by microalgae as well as the use of waste waters as source of water and nutrients for the same aim; the growth of microalgae using mankind - generated CO2 (e.g. flue gas) both to increase the growth rate and to bioremediate/biomitigation/decrease/consume this gas. Several other chapters deals with results concerning strategies, tools and results for the modification of selected strains in order to improve their ability to synthesize useful bioproducts, with special emphasis on molecular genetics, metabolic modeling and synthetic biology. One of the greatest problems in large scale application of microalgae, the harvesting, is presented with respect to flocculation and autoflocculation. Anaerobic digestion of microalgae feedstock and the potential of converting solar energy to electricity and chemical energy are also presented in this comprehensive book on biomass and biofuels from microalgae. Two chapters deal with the economics (including energy) of harvesting and downstream processing and of large-scale growing of microalgae for biofuels. This book trully presents some of the most promising existing microalgal biomass growth technologies and summarizes some of the novel methodologies for sustainable and commercial microalgae production.The editors and the other contributors to this book are very well known professionals in their field, thus each chapter is written in a very clear and concise way, having also a selective but rich bibliography. I am positively sure (including from my own experience as a reader) that the editors’ sentence „We trust the reader will enjoy the book as much as we enjoyed writing and editing it.” is TRUE. Prof. Ioan I. Ardelean

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Abstract - Pompiliu Manea, a tireless, prodigious and creative personality, very multidimensional in his approaches and expressions, vanishes surprisingly, leaving many projects unfinished, in a memorable day in the history of our culture - June 15 - the day of departure from this world of our national poet whom he venerated by devoting several pages and studies. Index Terms - Pompiliu Manea, career, didactic activity, scientific activity, textbooks and books published.

I. INTRODUCTION "Dear friends, This is the last message I will send with love to you, since I am leaving this world too early… I had needed some more time to finish together our already started projects for a better world! Unfortunately, just returned from a fantastic trip, which will remain untold, I went to another, from which I will never return! Yours sincerely, Pompi.”

II. POMPILIU MANEA This surprising and disconcerting message

announced the departure from us, the living ones, of a medical engineering personality who gave me the honor of being my friend and collaborator for over five decades, Prof. Dr. Eng. Pompiliu Manea. A moving formula chosen by the family to announce and to mourn the sudden death, in the middle of his creative effervescence, of their beloved, Pompi.

Bioengineering will be poorer for having lost one of its leaders - a passionate of this field, an inseparable part of modern biology and medicine.

Pompiliu Manea gathered in his effervescent and creative personality: bioengineering practitioner, researcher, inventor and innovator, teacher, academician, successful businessman, historic of medicine, patriot and man of culture, writer, glob-trotter, patron of the arts, philanthropist, all these dimensions (and others that I have maybe dropped) of his prodigious restless personality (in a creative sense), full of dynamism and chockfull of initiatives in his profession but also in many other areas of social life and culture, all of which that could be illustrated by his rich biography.

I know him from the beginning of his employment as a servant of medicine, of biomedical investigative and therapeutic technologies. Vocation, passion, innovation, trainer and head of school qualities are the characteristics that would explain his assertion as the leader in his area of expertise and also in other related fields - culture, history, journalism.

Therefore, I was painfully surprised by this unjust and brutal departure to eternity of this robust and dynamic Wallachian that came to Transylvania from Puranii - Teleorman County, where he first saw the light of day on 7 October 1935, after he had stopped for a while in Bucharest, where he left also his creative personality fingerprints.

III. CAREER His career began at an early age, from manual

labor, between 1945 and 1952 he worked as a smoothing tools car and tractor apprentice in his father's farm, Petre Manea Farm, beginning a path that would take him to the forefront of the profession to which he fully dedicated:

● Univ. Prof. Dr. Eng. ● Honorary Member of the Academy of Medical Sciences ● President founder of a successful private company: SC Techno Electro Medical Company (TEMCO).

In Memoriam POMPILIU MANEA: 40 Years of Medical Engineering in Transylvania

Prof. Dr. Constantin Bogdan Sf. Luca Chronical Hospital and Society of Writers and Publicists Doctors, Bucharest, Romania,

constantin.bogdan@yahoo.com

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Main stages of his formation: "Spiru Haret" Bucharest College, Postgraduate Medical Devices Technical School, Polytechnic Institute of Bucharest; after graduation several Postgraduate courses: Pedagogy (which he will serve his teaching career), the use of radioactive isotopes at the Institute of Physics (taught by Acad. Horia Hulubei). Then followed two doctorates: Technical University of Cluj-Napoca - PhD in technical engineering; Doctoral School of University of Technology Belfast Montbeliard, France, thesis: "Medical Engineering in Romania from 1948 to 2012". He participated in 27 training courses abroad.

Before briefly outlining significant data that shape the portrait of the personality of Eng. Pompiliu Manea, its worth to emphasize that his work in the last two decades has spurred the development and affirmation of medical engineering in Transylvania, so directly put into the service of quality and efficient healthcare. Besides, this will be revealed by the data to be presented below.

IV. DIDACTIC ACTIVITY Teaching Professor of Radiology and Nuclear

Medicine with The Sanitary Technical Postgraduate School Bucharest. Professor and Head of Medical Devices Discipline with The Sanitary Technical Postgraduate School, Cluj Napoca.

Lecturer, Faculty of Dentistry of UMF Cluj, discipline: engineering, maintenance and operation of dental medical devices. Lecturer with UMF Cluj, Faculty of General Medicine, courses of radiation physics, X-ray and radiation protection.

Since 1977, Extra-muros Professor with Technical University Cluj, Faculty of Electrical Engineering, Department of Electrical Engineering Fundamentals, radiological investigation techniques course.

Since 1998, Extra-muros Professor with "Gr.T.Popa" UMF Iaşi, Faculty of Medical Bioengineering, Medical Imaging Discipline.

Since 2000, Director of "Radiation Protection in Medicine and Technology” postgraduate course organized by Technical University and UMF Cluj.

This comprehensive didactic activity has meant a significant contribution to the development of bioengineering in particular in Transylvania, and moreover to the development of specialists and to the introduction into the

curricula - nursing schools, sanitary post-graduate schools, Medical Universities (Cluj, Iaşi), Technical University (Cluj) – of bioengineering disciplines and specializations.

V. SCIENTIFIC ACTIVITY Medical engineering expert activity - Ministry

of Health, Academy of Medical Sciences, the Romanian Academy - Cluj branch.

In the early 70s, together with the economist Prof. Dr. Alexandru Popescu and the undersigned have founded the Romanian Society of Economics and Sanitary Administration (SREAS), affiliated with former USSM (today the Romanian Medical Association) and began publishing the magazine of the same name, a magazine that still appears nowadays based on his material and editorial support, taken over, after his disappearance, by his son Eng. Bogdan Manea; I was honored to be deputy chief-editor.

Founder of other scientific and professional societies: National Society of Medical Bioengineering, Iaşi, 1990; National Society for Medical Engineering and Biological Technology, Cluj, 2000.

Scientific Congresses attended: European – 39, World - 15, National - 31.

He published 107 scientific papers, out of which 71 in his professional specializations, 20 in culture and 16 in the history of medicine and pharmacy.

He was a successful and generous businessman as not many, understanding to invest profits in encouraging and supporting research, organization of scientific meetings via sponsorships and donations; thus partially sponsored 30 scientific events, mainly in Transylvanian locations and 27 scientific and cultural books and also many cultural events.

VI. TEXTBOOKS AND BOOKS PUBLISHED

19, out of which as sole author: 8. He was co-author of books published together

with personalities such as: St. M. Milcu, Mircea Malita, Gleb Dragan, Crisan Mircioiu, N. Ghilezan.

Besides the teaching and scientific research, he is the author of the books: "Three years of my life (1986-1989) reflected in the secret service files," "Pilgrim on five continents", "Emil Racovita and his followers towards the South Pole," "Travel Log: Easter Island, Tahiti and Bora Bora Islands, New Zealand, Kingdom of Tonga, New Guinea”.

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He has carried out a rich cultural activity by initiating the Foundation "TEMCO Cultural Thursdays" which had 26 editions, supporting National Literary Saloon "Lit Poplars Rotonda" and others, being awarded 6 diplomas for cultural activity. His sustained cultural activity has been recognized through 24 other diplomas and honors.

He published an extensive study: "Scientific outlook in Mihail Eminescu's work."

VII. CLOSURE Pompiliu Manea, a tireless, prodigious and

creative personality, very multidimensional in his approaches and expressions, vanishes surprisingly, leaving many projects unfinished, in a memorable day in the history of our culture - June 15 - the day of departure from this world of our national poet whom he venerated by devoting several pages and studies.

His remembrance will be blessed at Ingimed XVI – November 26th 2015 and other meetings regrouping his friends, pupils and co-workers.

VIII. BIOGRAPHY Prof. Dr. Constantin Bogdan is PhD in medical

science, expert physician to the field of the geriatrics and gerontology. He is associate professor of the Sociology Faculty of Bucharest University. He has published more than one hundred papers and 300 scientific communications in International Journal and Conferences, and 12 scientific books. He is the President of the Paliatology and Thanatology Romanian Society and of the Bioetics –UNESCO National Committee.

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Abstract - Propelled by inexorable aspirations of human being, biomedical engineering resists to crisis and moves ahead across the world mainly under the impetus of the US scientists & practitioners. Europe unfortunately trails, while Romania presents an undesirable contrast between educational capabilities and the absorption of graduates into the public health system the majority of Romanians rely upon. As a whole, biomedical engineering holds the best promise to improve health and save lives on medium and long terms. Index Terms - biomedical engineering, case of Romania, education & job growth, Europe stagnation, goals of the Academy of Medical Sciences in Bucharest, US impetus, 2013-15 developments.

I. INTRODUCTION Aspiration to health and life, an inexorable

datum of humans propels healthcare industry as the world's biggest industrial sector, with a turnover approaching £100 billion per annum and an expanding rate of 7% per annum [1].

By 2010 world healthcare industry was including 15,000 registered manufacturers, about 10,000 generic devices and > 1 mil products & brands. About 50 percent of the 2007 diagnose & treatment technologies pertained to the last 10 years [2].

BME occupies a central place in healthcare industry and it is one of the few areas of engineering that is expected to continue to grow for many years, despite any crisis [1].

Branches or domains of biomedical engineering are summarized in Fig 1; beyond self-explaining labels, MEMS are micro electro-mechanic systems and MCT Engr is molecular, cell & tissue engineering [3].

II. THE US IMPETUS Rate of increase of BME education in the USA

before world financial crisis is shown in Fig 2. It is quite obvious that BME was towering aerospace and even the ubiquitous IT schooling. As for US Bureau of Labor Statistics (BLS) projections of job growth for 2012, they were (increase vs 2004-05) cf. [3]:

1. Healthcare and social assistance: + 32.4%; 2. BME and biotechnology: + 21 to 35%;

Fig. 1. Branches of BME

Fig. 2. Rate of increase of BME education in the USA

before last world financial crisis [3] 3. Nanotechnology; 4. Security and defense. Long term prospects of BME job descriptors

were assesssed in 2009 as follows [4]: - 2010 Median Pay: $81,540 per year, $39.20 per

hour; - Entry-Level Education: Bachelor’s degree; - Work Experience in a Related Occupation:

None; - On-the-job Training: None; - Number of Jobs, 2010: 15,700; - Job Outlook, 2010-20: + 62% (much faster than

industry average); - Employment Change, 2010-20: +9,700.

*

Biomedical Engineering 2015: Quo Vadis Europe?

*Radu Negoescu National Institute of Public Health, Str. Dr. Leonte Anastasievici, No.1-3, District 5, 050463, Bucharest,

Romania, *radu.negoescu@insp.gov.ro

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On December 29th 2000, president Clinton signed the National Institute of Biomedical Imaging and Bioengineering (NIBIB) Establishment Act to create the newest unit within the NIH campus in Bethesda, MD [5].

15 months later, the NIBIB (April 2002) received its first congressional appropriation of $112 million and began to operate fully.

The NIBIB domain encompasses research conducted at the nexus of biology, physics, engineering, mathematics, chemistry, and computer science.

In 2012: NIBIB budget was $ 350 million. NIBIB’s intramural research program

includes: - Laboratory of Cellular Imaging and

Macromolecular Biophysics; - Laboratory of Molecular Imaging and

Nanomedicine; - Division on High Resolution Optical Imaging; - Division on Biophotonics; - Biomedical Engineering Program.

NIBIB leads the world move to theragnostics as a treatment strategy that combines therapeutics with diagnostics based on a molecular insight offered by bioinformatics, genomics, proteomics, and functional genomics.

NIBIB also funds multidisciplinary research training through institutional training grants and individual fellowships, as well as in the context of individual research project grants.

III. EUROPE: A CLEAR-CUT GAP VS USA Recommendations of the Expert Policy

Workshop on BME under EU Parliament aegis (hosted by Th. Ulmer, MEP & EAMBS) on March 27, 2012 (except from 9 items):

1. […] It is thus important, that the European Union recognizes the full potential of BME and consequently promotes collaborative research in this field. Furthermore, Biomedical Engineering should be understood as a stand-alone discipline […].

2. […] promoting growth and well being, including Active and Healthy Aging.

3. Biomedical Engineering research should be made an explicit priority by introducing it into European Union policies and legislation […].

4. Strengthening of funding for Biomedical Engineering research, by dedicating specific research programs and by supporting the commercialization of research results, is essential.

5. More emphasis should be given to covering the full innovation cycle and focus on the

“missing mile”, the gap between the end of a research project and the provision of sufficient (clinical) evidence to attract private money.

7. Biomedical Engineering should be included into Horizon 2020, in the section on Key Enabling Technologies, as a distinct and separate field from biotechnology […].

8. A fair balance between biological, medical and technological research should be struck in EU research and innovation programs […]“.

Recommendations conclude that “given the societal challenges facing the EU Member States the current situation regarding Biomedical Engineering is unacceptable! The European Parliament would have to make sure that from now onwards Biomedical Engineering will receive adequate funding and support” [6].

IV. DEVELOPMENTS 2013-15 The 2013 EAMBES (Euro Alliance for Med &

Biol Engng & Science, main NG umbrella within European BME) recommendations for health technology research under Horizon 2020 EU program are [7]:

1) How to enable the early adoption of emerging technologies in healthcare that could offer cutting edge developments in industry?

Answer: Funding different types of projects: smaller ones with cutting edge approach, and larger ones with integration approach. In all types of projects a long term perspective to real applications in healthcare is needed.

2) How to ensure the integration of the multidisciplinary research, knowledge and technologies into approaches in clinical practice?

Answer: A series of calls should be implemented each with an emphasis on the integration of technologies to tackle real medical challenges. Integration of knowledge, talents and resources guided by medical needs is only able to place Europe as a global leader in BME.

3) How to provide resources to transfer the cutting edge technology into clinically proven products which will be reimbursed by the healthcare system?

Answer: To speed up the transfer of research findings to clinic and to provide resources, calls should stipulate prosecution of funded projects towards commercialization; unproven but potentially high payoff novel concepts in biomedical engineering must be also given a chance to funding.

The argumentarium behind them was:

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- The biomedical engineering sector is vital not only for the health and well-being of European citizens, but also for the “wealth” of the European economy. - In comparison to other sectors the growth rate of BME –related industry is about 5-7% per year. - In some countries it already is one of the leading high-tech industries. For example, in Finland health technology comprised 29% of Finland’s total high-tech industry exports in 2011. - BME is profoundly an ultra-multidisciplinary area which can be seen in research as well as in the products. Moreover, all phases from basic research to development, manufacturing and finally entry to the health market involve large number of stakeholders and players. - Because of this complexity Europe does not to date recognize the importance of this industry sector and end its specific needs as for research. - The US has already started dedicating programs for biomedical technology (eg. NIBIB creation), and as a result they are at the forefront of medical technology. - Unfortunately most research and funding in these areas takes place in “silos”. For example calls within the EU 7th frame work program were in majority referring to very specific technologies e.g. stem cells, bioinformatics, computational modeling or imaging. - However, having in mind the future needs of Europe’s ageing population, costs of healthcare and the societal challenges we faces, there is a need for the integration of multi-type of technologies into diagnostics, treatments, novel spare parts and rehabilitation. To gain new clinically applicable system this “integrative approach” is vital.

The 2014 setting can be illustrated comparing Europe to the USA at the world main (IEEE) (E)BME(S) forum. Fig 3 indicates BME geography: from 62 countries, the top five were USA, remote-followed by Japan, China, Canada and United Kingdom. In Europe UK was followed closely by Italy and France.

Fig. 3. BME geography 2014 [8]

Fig. 4. BME topics at IEEE-EBMS Conference 2014 As for topics: 1. Brain was the 1st; because

“EEG”, “transcranial”, “neural”, “brain-computer- interface” and “cortical” are brain-related, the brain is the hottest BME research. Other popular areas were 2. Heart, wireless, wearable and sleep, followed by 3. Automatic monitoring and modeling.

In the same vein, the top 10 BME Universities in 2014 were [9]:

1. The Harvard School of Engineering and Applied Sciences;

2. Rochester Institute of Technology; 3. The University of Sheffield; 4. ETH Zürich (Eidgenossische Technische

Hochschule); 5. The Swiss Federal Institute of Technology,

Lausanne; 6. The Georgia Institute of Technology; 7. The University of Cambridge; 8. The University of Twente at Enschede

(Netherlands);

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9. The John Hopkins School of Medicine; 10. The Duke University. Apparently USA vs. Europe is a draw: 5 to 5.

However, as shown before, this is not yet reflected by industry or science output!

To compare with EABMES recommendations, here are in 2015 BME-related Horizon 2020 calls for 2016-17 in public health area (the most integrative domain) [10]: - SC1-PM-17–2017: Personalized computer models and in-silicon systems for well-being - true BME integrative challenge.

Proposals should aim at the development of new integrative dynamic computer-models and simulation systems of acceptable validity, with the potential to being reused, build on open service platforms and with application in well-being, health and disease. - SC1-HCO-12–2016: Digital health literacy – BME associated.

Proposals should provide support for the improvement of digital health literacy of citizens, and, in particular, should design open access online courses for different population cohorts including children and the elderly, supporting an interactive learning environment. - SC1-PM-05–2016: The European Human Bio-monitoring Initiative – BME associated.

The objective is to create a European joint program for monitoring and scientific assessment of human exposures to chemicals and potential health impacts in Europe.

A bit but not much integration!

V. CASE OF ROMANIA: GAP YET LARGER Despite historically favorable premises, and

early 2000 introduction of professions of Clinical Engineer under code no. 221401 and Medical Bioengineer code no. 222907 into the Classification of Occupations in Romania (COR) by diligences of Bucharest AISTEDA University and Iasi University of Medicine& Pharmacy/Faculty of Medical Bioengineering respectively, actual setting is precarious not because of schooling capabilities and total number of practitioners but for the very weak absorption into the health public system the majority of Romanians rely upon.

All these happen on a background of a modest technological endowment of most hospitals & clinics and under-usage of high-tech equipments available in big towns and university hospitals.

BME prospects in Romania

At present the Academy of Medical Sciences (ASM) in Bucharest tries to promote improvements within the framework of EU structural funds 2014 – 2020, Infrastructure chapter.

Appealing the EU structural funds 2014 - 2020 is a necessary condition, given the actual and next future setting of budgetary appropriations for health in Romania.

The ASM pledge concerning BME in Romania Novel regulations concerning the

technological support of medical care in Romania, as: - establishing BME departments in big hospitals (county, university) starting from an 1/8 ratio between the specialized technical personnel (including bioengineers with research labs) and the medical staff (T to M ratio), with gradual evolution towards 1/5 until 2015; - establishing clinical engineering departments with medium size hospitals or small hospital networks starting from an 1/10 T to M ratio with gradual evolution towards 1/6 until 2015; - when updating hospital technological endowment, mandatory appropriation of 20 percent of the investment for biomedical engineers’ remuneration.

VI. CONCLUSION Propelled by inexorable aspirations of human

being, Biomedical Engineering resists to crisis and moves ahead across the world mainly under the impetus of the US scientists & practitioners.

Europe unfortunately trails, while Romania presents an undesirable contrast between educational capabilities and the absorption of graduates into the public health system the majority of Romanians rely upon.

As a whole, Biomedical Engineering holds the best promise to improve health and save lives on medium and long terms.

VII. QUO VADIS EUROPE? “… to Rome, of course, to crucify someone,

yet not St. Peter once more, but MONEY-RELATED GREED, ABHORRENCE AND EGOISM blocking communication & empathy among cultures, BME universities and individuals and opposing conversion of my great minds & thoughts into generous deeds for sake of healthier fellow Europeans.

…. and, by the way, to retrieve a bit my inborn Christianity!”

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* A final message for younger fellows from

ICPE-CA research training centers: Qualify as a biomedical engineer and strive

to put your next competence in service of health-needy people in one of the most salutary and humanly accomplishing ways!

VIII. REFERENCES [1]www.science-engineering.net/.../medical-engineering, UK, visited Nov, 2012. [2] GMDN Ag., Med. Techn. Brief 2007; cf. Sontea et al, Int. Conf. Nanotechnology & BME, Chisinau 2011. [3] Akay M., Keynote at the 2nd E-Health & Bioengineering Conference, Iasi and Constanta, September 2009. [4] ***US Quick Facts on Biomedical Engineers. BLS, Occupational Outlook Handbook, 2012-13 Edition: http://www.bls.gov/ooh/architecture-and-engineering/bio medical-engineers.htm. [5] http://www.nibib.nih.gov/. [6]http://www.eambes.org/news/report-on-the-expert-policy-workshop-on-biomedical-engineering. [7] Hyttinen J., Glasmacher B., Lohmann K., Linnenbank A., Jamsa T., Kennedy J., EAMBES position paper for Horizon 2020 research in technologies for health and medicine: http://www.eambes.org/contents/public-repository/ EAMBES %20position%20paper%20Horizon 2020_mc.pdf. [8]https://www.linkedin.com/pulse/20141007194613-43011485-key-trends-in-biomedical-engineering-a-look-back-at-embc-2014. [9]http://justengineeringschools.com/top-bio-medical-engineering-schools-in-the-world/. [10]http://ec.europa.eu/research/participants/data/ref/ h2020/ wp/2016_2017/main/h2020-wp1617-health_en.pdf

IX. BIOGRAPHY Radu M. Negoescu got the MS degree in 1969 from the

Bucharest Polytehnic University then obtained the PhD in electronic engineering from the Institute of Nuclear Physics & Engineering in 1986, and the MPH degree in public health management from the University of Medicine and Pharmacy in 2001.

His employment records include the National Institute of Public Health in Bucharest - where he is currently the head of Health Promotion Unit, National Institutes of Health (Bethesda, MD), and Totts Gap Institute (Bangor, PA, USA).

His research includes cardiovascular bioengineering, biosignal processing and neurocardiology. He is a Member of Honor of the Academy of Medical Sciences and a senior member of the IEEE.

24

25

Abstract - Human teeth show various conditions requiring removal of dental pulp, pulp which is in a space that the morphology is difficult to predict and harder known exactly.

The main purpose of this research is in studying the reliability of X-Ray images in relation with the real morphology of the endodontic space.

In order to achieve the main purpose, the research will be organized around two main tasks: a) Obtaining radiologic images of the endodontic space by

methods of medical investigation and obtaining radiologic images by means of high resolution investigation;

b) Comparing the images obtained via the two methods. The advanced technology of the X-ray microtomograph

scanner combined with the ultra high performance segmentation of voxelized data software made it possible to obtain clearly superior images (resolution improved about 20 times) to those obtained through medical investigation methods. At the same time, 3D images were obtained that help us look at the real morphology of the endodontic space. Index Terms - Endodontic space, medical imaging, segmentation of imaging data, 3D medical imaging.

I. INTRODUCTION Human teeth show various illnesses conditions

requiring removal of dental pulp. Because of varying morphology and the possibility of the existence of branches, secondary or accessory channels, removal of dental pulp maneuvers are difficult and sometimes even impossible to carry out correctly and completely. Using dental microscope makes the dentist's work much easier. However, it allows only the viewing of straight line canals with image magnification up to 25 times.

Lack of ability to know the exact shape and dimensions of the three-dimensional root canal system can cause failures of endodontic treatment.

The usual method of investigation which overcame this drawback is the radiographic imaging of the endodontic space and bone structure of the alveolar ridge, Radiology is used in dentistry interventions endodontic surgery,

implant surgery, orthodontic intervention and as investigation for the purpose of evaluating the health of the oral cavity.

II. THE OBJECTIVE OF THE STUDY The primary endpoint of this study is the

assessment of the medical radiology in relation to the actual morphology of three-dimensional root canal system (endodontic space).

To achieve its primary objective, the study will be organized around two main tasks:

a) Obtain radiological images of endodontic space by a conventional medical Con Beam Computer Tomograph and by means of an Industrial X-Ray Microtomograph;

b) Comparison of the relevant images obtained by the two means.

III. DESCRIPTION OF THE EXPERIMENTAL RESEARCH

Through this study we intend to investigate the ability of the medical imaging methods to accurately reveal details of the human teeth endodontic space.

A. Materials and Method We chose a real case of a patient M.O. with

definite indication for the extraction of the third molar in the quadrant I - 18, due to malposition eruption and occlusal trauma cause.

The area of intervention underwent a clinical and imagistic evaluation by Con Beam Computer Tomograph.

After the extraction the third molar was preserved in formalin for further investigations.

It is worth noting that the tooth shows no coronary or root cavities or fillings.

A1. Diagnostics Imaging Apparatus - Medical imaging equipment Con Beam Computed Tomograph Planmeca 2011; - Industrial X-ray Microtomograph (Combined 3D X-Ray microtomograph);

Material studied:

Comparative Analysis of Cone Beam 3D Medical and Industrial

*Corina Cîrcei, **Ciprian Răcuciu, ***Ion Tiseanu, ****Adrian Sima *, **Titu Maiorescu University Bucharest, Dâmbovnicului, no. 22, District 4, Bucharest, Romania;

***, ****Plasma Physics and Nuclear Fusion Laboratory National Institute for Lasers, Plasma and Radiation Physics (INFLPR), Atomistilor no. 409, 077125, Bucharest-Măgurele, Romania,

***tiseanu@infim.ro

26

- a real clinical case; - one tooth extracted.

B. Method Stage1. Scanning the tooth using conventional equipment of medical investigation.

We chose for investigation a machine Con Beam Computer Tomagraf Planmeca, year of manufacture 2011. Operation parameters were 90 kVA inverter power, 12 mA anodic current, with a DAP value of 1302.1 mGy*cm2 and exposure time of 12,258 seconds.

Purpose of this stage is to obtaining radiological investigation actual medical treatments used in dental 3D imaging.

Fig. 1. Medical Radiology Data Sheet.

Stage 2. X-ray microtomography scanning of the extracted tooth and image data processing.

2.1. Scanning the tooth with X-Ray micro-

tomography. Scope: The purpose of this stage is to obtain

highly accurate 3D reconstructions of the endodontic space. These images will be compared with the actual morphology of endodontic space.

We chose an industrial X-ray microtomograph developed in the National Institute for Laser, Plasma and Radiation Physics, Măgurele.

The key components are: i) a compact X-ray source with maximum high

voltage of 50 kV, maximum power of 50 W and a measured focus spot of 42 µm;

ii) a 1K x 1K flat panel CMOS X-ray detection system with pixel size of 48 µm;

iii) a XYZ(Theta) motorized micrometric manipulator. The overall performances of the X-ray microtomograph are as follows: spatial resolution < 20 µm, density resolution > 1%,

maximum size of the samples ΦxH = 40x200 mm2. The microCT scan runs with typical exposure

parameters of 48 kV @ 750 mA and 2 sec exposure time per image acquired resulting in an exposure of 1800 mA sec per scan.

The probe took an amount dose of exposure in fascicule equal to (28 x 2400) µGy = 67.2 mGy, and exposure time was 2400 seconds.

This dose of exposure was measured with the PTW - TM 23-342 sensor, a Low energy sensor.

It should be noted that the high precision equipment has no application in medical diagnostic due to the relatively large equivalent dose (≤ 70 mGy) and long exposure time.

2.2. Tomography reconstruction and image

processing. This reconstruction was performed with the

cone-beam Filtered Backprojection algorithm (FDK Method).

Reconstructed volumes of 1024 x 1024 x 1024 voxels allow visualization and measurement of the minimum dimensions of 0.0146 mm on any axis.

The image processing protocol to obtain the 3D images of the root canal space is based on thresholding and segmenting the reconstructed volume and was performed with the VGStudio MAX software. Stage 3. Comparative study of images obtained with the medical and the industrial scanners.

First, as shown in the figures bellow, we conducted a qualitative comparison of similar tomographic sections obtained by medical investigations of Phase I and by the X-ray microtomograph in Stage1 and Stage 2.

In the radiological images a) ,b) and c) obtained with the medical tomograph the voxel size is 320 µm while the industrial microtomograph images d) are resolved to a voxel size of 14.6 µm, i.e. approximately 20 times smaller.

27

c)

a)

b) Fig. 2. Tomographics sections of the 1/3 coronal the tooth radicular pulp.

a) Axial cross-sections – Medical 3D X-Ray CBCT; b) Radiology Sheet: top left: coronal cross-section – Medical 3D X-Ray CBCT;

top right: sagittal cross-section – Medical 3D X Ray CBCT; down left: axial cross-section – Medical 3D X-Ray CBCT;

down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT; c) Axial cross-section – Industrial Combined 3D X-Ray microtomograph.

c)

a)

b)

Fig. 1. Tomographics sections of the coronal tooth pulp cavity floor. a) Axial cross-sections – Medical 3D X-Ray CBCT;

b) Radiology Sheet: top left: coronal cross-section – Medical 3D X-Ray CBCT; top right: sagittal cross-section – Medical 3D X Ray CBCT; down left: axial cross-section – Medical 3D X-Ray CBCT;

down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT; c) Axial cross-section – Industrial Combined 3D X-Ray microtomograph.

28

a)

c)

b)

Fig. 4. Tomographics sections in the apical third of radicular pulp. a) Axial cross-sections – Medical 3D X-Ray CBCT;

b) Radiology Sheet: top left: coronal cross-section – Medical 3D X-Ray CBCT; top right: sagittal cross-section – Medical 3D X Ray CBCT;

down left: axial cross-section – Medical 3D X-Ray CBCT; down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT;

c) Axial cross-section – Industrial Combined 3D X-Ray microtomograph.

a)

b)

c)

Fig. 3. Tomographics sections of the half radicular pulp. a) Axial cross-sections – Medical 3D X-Ray CBCT;

b) Radiology Sheet: top left: coronal cross-section – Medical 3D X-Ray CBCT; top right: sagittal cross-section – Medical 3D X Ray CBCT; down left: axial cross-section – Medical 3D X-Ray CBCT;

down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT; c) Axial cross-section – Industrial Combined 3D X-Ray microtomograph.

29

As it will be shown in the next section of the

paper the tomography images generated with the industrial microtomograph allowed us to perform accurate dimensional measurements.

a)

b)

c)

d)

e)

Fig. 5. Tomographics sections of the apical radicular pulp. a) Axial cross-sections – Medical 3D X-Ray CBCT; b) Radiology Sheet: - top left: coronal cross-section – Medical 3D X-Ray CBCT; - top right: sagittal cross-section – Medical 3D X Ray CBCT; - down left: axial cross-section – Medical 3D X-Ray CBCT; - down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT; c), d), e) Sequential axial cross-section separated by 0.65mm –Industrial Combined 3D X-Ray microtomograph.

30

Fig. 6. Axial cross section in the apical zone by approximately 0.6 mm.

Fig. 7. Axial cross section in the apical zone by approximately 1.2 mm.

31

Fig. 8. Axial cross section in the apical zone by approximately 1.8 mm.

Fig. 10. Sagittal cross section of the tooth.

Stage 4. 3D representation of the endodontic space.

Images below were obtained by the processing of the reconstructed volumes with the VGStudio-MAX 2.2 software (http://www.volumegraphics.com/en/products/vg

studio-max). One can say that the 3D images faithfully convey the real form of the endodontic space in terms of shape, dimensions and canals path. Also this representation allows us to look at the endodontic space from any angle.

32

Fig. 11. Image of the 3D reconstruction used the Combined 3-D X-Ray industrial microtomograph, lateral view.

33

Fig. 12. Image of the 3D reconstruction used the Combined 3-D X-Ray industrial microtomograph, front view.

34

Fig. 13.Image of the 3D reconstruction used the Combined 3-D X-Ray industrial microtomograph, apical view.

35

IV. CONCLUSIONS 1. Advanced X-ray microtomography

combined with powerful data processing software made it possible to obtain superior images with enhanced resolution of about 20 times over those obtained through conventional medical imaging. At the same time the microtomographic scanner were able to provide realistic 3D images of the actual morphology of the endodontic space.

2. Industrial X-ray microtomography has a definite utility in experimental in vitro studies highlighting real morphology and details

undetectable in medical investigations. It is envisaged that one can lay the groundwork for new methods and technologies in addressing treatment in endodontics with emphasize on the need for advanced properties such as viscosity, fluidity and hydrophilic nature of new materials to be used in endodontic fillings.

3. Comparing the imaging results with radiation doses involved in the investigation, imposes the need to explore other methods of dental imaging investigations.

Fig. 14. Image of the 3D reconstruction used the Combined 3D X-Ray industrial microtomograph, coronal view.

36

4. Further studies will continue by using an advanced industrial X-ray microtomograph with X-rays energies up to 150 keV and spatial resolution down to couple of microns. This will

allow us to obtain images free of artifacts that can be better processed with an advanced series of algorithms.

V. APPENDIX - IMAGES

Fig. A1. Medical 3D X-Ray axial cross-sections of the coronal tooth pulp cavity floor (Radiology Sheet):

- top left: coronal cross-section – Medical 3D X-Ray CBCT; - top right: sagittal cross-section – Medical 3D X Ray CBCT; - down left: axial cross-section – Medical 3D X-Ray CBCT; - down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT. 

Fig. A2. Medical 3D X-Ray CBCT axial cross-sections of the coronal tooth pulp cavity floor (Radiology Sheet).

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Fig. A3. Industrial Combined 3D X-Ray microtomograph, axial cross-section of the coronal tooth pulp cavity floor.

Fig. A4. Medical 3D X-Ray axial cross-sections of the 1/3 coronal the tooth radicular pulp (Radiology Sheet):

- top left: coronal cross-section – Medical 3D X-Ray CBCT; - top right: sagittal cross-section – Medical 3D X Ray CBCT; - down left: axial cross-section – Medical 3D X-Ray CBCT; - down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT.

38

Fig. A5. Medical 3D X-Ray axial cross-sections of the 1/3 coronal the tooth radicular pulp (Radiology Sheet).

Fig. A6. Industrial Combined 3D X-Ray microtomograph, axial cross-section of the1/3 coronal the tooth radicular pulp.

39

Fig. A8. Medical 3D X-Ray axial cross-sections of the 1/3 coronal the tooth radicular pulp (Radiology Sheet).

Fig. A7. Medical 3D X-Ray axial cross-sections of the half coronal the tooth radicular pulp (Radiology Sheet): - top left: coronal cross-section – Medical 3D X-Ray CBCT;

- top right: sagittal cross-section – Medical 3D X Ray CBCT; - down left: axial cross-section – Medical 3D X-Ray CBCT; - down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT.

40

Fig. A9. Industrial Combined 3D X-Ray microtomograph, axial cross-sections of the 1/3 coronal the tooth radicular

pulp (Radiology Sheet).

Fig. A10. Medical 3D X-Ray axial cross-sections of the apical thir radicular pulp (Radiology Sheet): - top left: coronal cross-section – Medical 3D X-Ray CBCT;

- top right: sagittal cross-section – Medical 3D X Ray CBCT; - down left: axial cross-section – Medical 3D X-Ray CBCT; - down right: buccal view of 3D reconstruction – Medical 3D X-Ray CBCT.

41

Fig. A12. Industrial Combined 3D X-Ray microtomograph, sequentially axial cross-sections of the apical third radicular

pulp (Radiology Sheet) – sequence 1.

Fig. A11. Medical 3D X-Ray axial cross-sections of the apical third radicular pulp (Radiology Sheet).

42

Fig. A13. Industrial Combined 3D X-Ray microtomograph, sequentially axial cross-sections of the apical third radicular

pulp (Radiology Sheet) – sequence 2.

Fig. A14. Industrial Combined 3D X-Ray microtomograph, sequentially axial cross-sections of the apical third radicular

pulp (Radiology Sheeet) – sequence 3.

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VI. REFERENCES [1] Arnaldo Castellucci, “Endodontics”, Volume I, II Tridente, Editioni Odontaiatriche, pp. 245-314. [2] Walton R. E., “Diagnostic imaging A. endodontic radiography”, Ingle J. I., Bakland L. K., Baumgartner J. C., Eds., Ingles’ Endodontics, 6th edition, Hamilton, Canada, BC Decker, 2008, pp. 554. [3] Tiseanu I. et al., “Fusion Engineering and Design”, Vol. 86, Issue 9-11, October 2011, pp. 1646-1651. [4] http://www.volumegraphics.com/en/products/vgstudio-max.

VII. BIOGRAPHIES Corina Cîrcei, Assistant Lecturer, dentist, Ph.D.,

worked in the Titu Maiorescu University, Bucharest, Romania, 5 years in higher education. Position held: Assistant Lecturer at the Endodontics Department of Faculty of Dentistry.

Scientific activity: 2 books, 3 papers published in impact journals, 6 papers published in national proceedings conferences, or national with international participation. Domains of excellence: dentistry, endodontics.

Dr. Ion Tiseanu is a senior scientist specialized in the field of radiation. He participated, in the last 15 years, at the design, construction and application of several dedicated X-ray imaging instruments: microtomographs, microbeam absorbtion/fluorescence and combined microCT/microXRF systems. He was a scientific consultant of leading manufacturers of computer tomography systems: Wealischmiller (HWM) GmbH and RayScan GmbH, Germany, etc. Thus, in cooperation with UHS, Dr. Tiseanu developed a new device and image reconstruction method - oblique view cone beam tomography (OVCB). Other X-ray CT projects implemented in cooperation with industry are: Audi AG Neckarsulm, Eurocopter and EADS Germany, etc. Recently he proposed a new procedure for the non-destructive inspection of Cable-in-Conduit-Conductor type super conductor cables based on microfocus computed tomography. That procedure has applicability at the Quality Control of Cables for advanced fusion systems (ITER, DEMO) and Accelerators (LHC-CERN). Beside this intense cooperation with industry Dr. Tiseanu was principal investigator in several European and national research projects and is author or co-author of about 80 ISI indexed papers.

Ciprian Răcuciu, full professor, engineer, Ph.D., doctoral studies coordinator, worked in the Military Technical Academy, 22 years in higher education. Position held: International Relations and Community Programs Institutional Coordinator, Head of the Communications Department. Scientific activity: 10 books published by prestigious publishing houses, 24 papers published in journals (11-ISI indexed), 39 papers published in international proceedings conferences, or nationals with international participation (7-ISI indexed); international research contracts: 4 - project manager, 2 - research teams member; national research contracts (in the last 10 years): 7 - project manager, 12 - research teams member; Member of IEEE professional association. Domains of excellence: coding information methods, information security methods, communications security systems, radio-relay communications systems.

Adrian Sima is born on 6 February 1983, in Cugir Alba. He is scientist engineer to the National Institute for

Lasers, Plasma and Radiation Physics and his title of qualification is master in automation and system engineering control at University Politehnica of Bucharest.

His present preoccupations are: -C/C++ and Labview software developer; -porting and parallelizing image reconstruction programs; -data acquisition and processing.

44

45

Abstract - The present accelerated development of microelectronics led to new health care applications that previously could not have been designed and here can be cited the active implanted medical devices − IMD. But their supply implies the existence of a power source, usually a battery whose lifetime is limited and must be changed so it implies repeated incisions. This paper presents an analysis of Transcutaneous Energy Transfer − TET for recharging the batteries from the IMDs based on wireless technology. It is shown that, by using magnetic resonance (WiTricity), the energy and data transmission are not restricted by the position of the patient (receiver) with respect to the source (transmitter). Index Terms - Implantable medical devices, transcutaneous energy transfer, wireless charging, data transfer, magnetic resonance application, safety.

I. INTRODUCTION Implanted medical devices have gained a

widespread in recent decades. Modern microelectronics has allowed the

appearance of some reduced size IMDs, less invasive and with a longer lifespan. Currently, they serve both for therapeutic actions and for monitoring some physiological parameters essential to ensure the quality of life.

An overview of some active IMDs types is given in Fig. 1 [1].

Fig. 1. Implanted devices to solve various medical

problems.

Among the most widespread active implantable medical devices are artificial hearts, implantable heart monitors and defibrillators, pacemakers, neurostimulators, ventricular assist devices and so on. An example of a complete device is shown in Fig.2 [2]

a)

b)

Fig. 2. a) – classical pacemaker (the programming unit, the pacemaker itself, the excitation probe; b) – remote

monitoring system. The dimensions of the implanted pacemaker

(pulse generator) are determined mainly by the power battery size whose lifespan is between 3 and 10 years. The patient can be supervised on-line through a Wi-Fi secure connection or by

Current State and WiTricity Technology Application Perspectives for Implantable Medical Devices

*Andrei Marinescu, **Mihai Tarata, ***Mihai Iordache *National Institute for Research, Development and Testing in Electrical Engineering (ICMET), B-dul Decebal,

No. 118A, 200746, Craiova, Romania; **University of Medicine and Pharmacy of Craiova Medical, Informatics & Biostatistics Dept., Petru Rareş, No.

2, 200349, Craiova, Romania; *** University Politehnica of Bucharest, Electrical Engineering Faculty, Splaiul Independenţei, No. 313,

District 6, 060042, Bucharest, Romania, *amarin@icmet.ro, **mihaitarata@yahoo.com, ***mihai.iordache.44@gmail.com

46

using a smartphone. Under this form, one obtains an ideal IMD that ensures the electrical stimulation and the monitoring/response of the patient under treatment.

Although there is a huge progress up to now, still remain to be solved at a new technological level, the issues related to power supply and to dimensions reduction of the active IDMs. In this way, it could lead to the implantation of a sensors network that will monitor the human body in certain risk conditions.

This paper presents the application of contactless inductive coupling for transcutaneous energy transfer (TET) for recharging the power batteries for the IMDs, which eliminates the necessity of multiple incisions and which can help to decrease the implant size by reducing the battery capacity. We discuss especially the application of wireless technology in WiTricity version, with magnetic resonance coupling that ensures reasonable transfer efficiency at distances and for variable positions with respect to the transmitter. It is analyzed the transfer efficiency, the coupling factor of a planar spiral coils, the patient safety for electromagnetic radiation exposure and one makes suggestions for future research in this field.

II. MAGNETIC CONTACTLESS TRANSCUTANEOUS ENERGY TRANSFER

Contactless energy transmission, although known from the late XIXth century, has gained a widespread use in recent decades due to many applications in low and high power electronics [3]. One of the materializations of this transmission form is that which takes place in a magnetic field at a distance R between the transmitter and an arbitrary point in the field where the receiver is placed in Region 1 from Table I, where D is the largest source size (antenna) and λ is the wavelength. TABLE I. The electromagnetic coupling mechanism according to [4, 5].

Region Distance (R) from the source

1 Reactive near-field region λ

<3

62.0 DR

2 Intermediate (or radiating) near-field (Fresnel) region λ

<<λ

23262.0 DRD

3 Radiative far-field (Fraunhofer) region λ

>2

2 DR

Region 1 is the reactive near-field zone in

which there is no electromagnetic radiation. The analysis made by the authors in IEEE Xplore database, with the keyword “Wireless power transfer and biomedical science” shows the researchers interest and also an explosive growth of the indexed publications in this field.

Fig. 3. The number/year of IEEExplore indexed

publications for the domain: “Wireless power transfer and biomedical science”.

As follows, we will analyze the two realization

forms of the near-field magnetic coupling in which, compared to the electric field coupling, has the advantage that is not so sensitive to the presence of dielectrics placed in the power transfer path.

A. Magnetic Induction (MI) versus Magnetic Strong Resonance Coupling (MSRC)

The classical form of the contactless transmission by magnetic induction is known from Tesla [6] and from the asynchronous motor invention (induction motor) and it actually represents a transformer with separable coils (L1, L2), usually in air, characterized by a coupling factor k of reduced value as in Fig. 4.

Fig. 4. Equivalent diagram of a magnetic inductive power

transfer.

Here, to improving the power transfer properties, a leakage inductivities compensation takes place, primary and secondary, such that these circuits to have the same resonance frequency [7].

In IMDs case, one should take into account that the transmission takes place in media with different dielectric properties, dependent on working frequency [8], [9] as shown in Fig.5 where in addition is specified that besides the

47

power transfer also system status data can be transmitted.

If one denotes by Qp and Qs the quality factors of the primary and secondary circuits, the power transfer efficiency η can be written as [10]:

QQk

QQk

p

sp2

2

1+=η (1)

from where it results that the value of the coupling factor k is decisive for the transfer efficiency.

Fig. 5. A complete contactless inductive transmission

system for IMDs [9].

If one denotes, for the planar coils case, by d the distance between the coils and by rm the geometrical average of the outer radius of the coils rp and rs, then, in the reactive zone of the magnetic near-field, η = f (1/d3) for d >> rm or η ≤ 40% for d >= rm.

This magnetic inductive system requires

precise coils alignment [11] and can only provide power over a small gap (few cm). Although it is widely discussed in literature [12], this short-range power transfer is not acceptable to generalized application, on large scale, at IMDs.

Strong Magnetic Resonance Coupling (SMRC) described in [13], [14], with the commercial name WiTricity, uses the same principle as the magnetic inductive coupling but allows the power transmission for distances much longer than that corresponding to rm. This is the reason for which it is called mid−range power transfer. The wireless transmission system (Fig.6) [15], in this case, consists of four resonant magnetic coupled circuits, grouped two and two, one after another by k12, k23 and k34 but also by couplings from the distance k13, k14 and k24. The coils L1and L2 now forms the transmitter Tx

where the coupling is very tight (k12→1), L3 and L4 forms the receiver Rx with also a very tight coupling (k34→1) and the coupling Tx – Rx ensures the effective power transmission that has a reduced coupling due to the big distance (d) between the coils L2 and L3.

For the general case, the global power transfer efficiency for the SMRC system is [16]:

]41][)1)(1[())()((

323432

22332

22343

23421

212

4323432

22321

212

QQkQQkQQkQQkQQkQQkQQkQQk

+++++=η

(2)

Fig. 6. Mid – range power transfer.

If one takes into account the values of the

above coupling factors, the relationship (2) becomes:

32223

32223

1 QQkQQk

+≅η for d >>rm (3)

The relationship (3) is similar to relationship

(1) but in this case the low k23 can be compensated by a high Q2 and Q3 (independent of source and load resistance).

In the original paper [13] the coils L1 up to L4 are helical coils that occupy an important space.

The solution proposed in this paper consists of using some coplanar spiral coils where L1 is placed inside L2 and L4 is placed inside L3.

The following performances are expected from applying the SMRC to IMDs: - Accept different size for Rx (IMD) and Tx; - Flexible orientation between Rx and Tx; - Use non-radiative magnetic field to transfer energy; - Meets international safety guidelines for human exposure

48

- Work in an extended wireless range (up to few meters) directly or by resonant repeaters; - Small batteries or no batteries.

B. Method for Coupling Factor Determination From the above analysis it results that the

coupling factor k is a very important parameter for characterizing any contactless power transfer. The method described in details in [17] uses a VNA (Vector Network Analyzer) for determining the frequency characteristics for a high power wireless power system and it has been applied for the case of some small power inductive couplers (Fig. 7) specific for IMDs with the characteristics given in Table II.

Fig.7. PCB Spiral Coils.

TABLE II. PCB Spiral Coils Data.

Coils Turns N

Turns width [mm]

Pitch [mm]

OD [mm]

Inductance at 25 kHz

[µH]C1 10 1,2 1,2 50 2.35 C2 5 1,2 1,2 33 0.70 C3 5 1,2 1,2 28 0.54 C4 10 0,6 0,6 29 1.75 C5 10 1,2 1,2 55,5 3.10 C6 10 1,2 1,2 47,5/45 2.36 C7 20 0,6 0,6 51 8.76 C8 5 1,2 1,2 25/23 0.54

Table III. VNA Coupling factor and transformation ratio for C1 – C2 Coils.

d [mm]

Middle Band |G21|

Rx to Tx

Middle Band |G12|

Tx to Rx

k n nmed

2 0,294046 1,156032 0,583 0,504 0,516 (+3.2%)12 0,122354 0,407108 0,223 0,528

where: 1221 GGk ⋅= , 1221 / GGn = .

In Table III are presented the results of the determination of the coupling factor and of the transformation ratio of the coupler realized with coils C1 and C2 both valid in the frequency band

34 kHz up to 8.5 MHz.

III. TRANSCUTANEOUS ENERGY TRANSFER VERSUS SAFETY

Electrical Safety is quantified based on the Specific Absorption Rate (SAR) levels to limit tissue heating due to conduction and relaxation losses, the dominant loss mechanisms in tissues [18]. The optimal frequency for minimizing coil losses is different from the one for minimizing tissue losses. Hence electrical safety demands frequency selection to reduce the overall losses. Using the restrictions available in [19], [20] for general public exposure one can estimate the maximum power output of the link. Between 100 kHz and 30 MHz the estimated maximum power is close to 20 mW;

Bio-compatibility: copper are not biocompatible, so the coils need to be sealed hermetically;

Mechanical safety needs smooth edges and a flexible, conformal design;

In conclusion: trade-offs between performance and biocompatibility & conformity is still in progress.

IV. CONCLUSIONS

• Strong Magnetic Resonant Coupling (SMRC) is a new wireless power transmission technology; • SMRC is best for IMDs, technique under development in the world; • Large interest to apply this technology from research and industry; • Some solutions and developments which could be covered:

- Establishing essential characteristics of a charging system for different IMDs;

- High Q coils development on flexible PCBs - Improving coupling factor and efficiency

(e.g. with metamaterials); - SAR measurement and simulation from 0.1

up to 10 (100) MHz taking in account the variation of skin and tissue dielectric properties;

- Low power compact amplifier development (e.g. class E).

V. REFERENCES 1] IMD Shield: Securing Implantable Medical Devices, Available: http://groups.csail.mit.edu/netmit/IMDShield/ Accesed 24.11.2015. [2] Pacemaker System, Available: www.medtronic.com

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[3] Contactless Power transfer, Available: http://www.acero.ro/cpt.html, Accesed: 23.11.2015. [4] A.J.Schwab, W.W.Kuerner, Ch.5, in book: ”Compatibilitate Electromagnetica”, ISBN: 978-87-92329-23-3, Editura AGIR, Bucuresti, 2013, (Translated from German). [5] G. R. DeJean, “Wireless Evanescent Coupling and its Connection to the Latest Developments Presented by Researchers at MIT”, Microsoft Research, pp. 1 – 9, 2007. [6] M. Iordache, Lucia Dumitriu, D. Niculae, Georgiana Zainea, Chapter 1 – “Power Transfer by Magnetic Induction Studied by Coupled Mode Theory”, in book, “Wireless Power Transfer”, J. I. Agbinya (Editor), ISBN: 978-87-92329-23-3, River Publishers Series in Communications, Denmark, 2012, pp. 1 – 40. [7] D. Niculae, M. Iordache, Lucia Dumitriu, “Magnetic Coupling Analysis in Wireless Transfer Energy”, Proceeding of the 7th International Symposium Advanced Topics in Electrical Engineering – ATEE’11, 12-14 May 2011, Bucharest. [8] S. Gabriel, R.W. Lau, C. Gabriel, “The dielectric Properties of Biological Tissues: II. Measurements in the Frequency Range 10 Hz to 20 MHz”, in Phys. Med. Biol., Vol. 41, pp.2251-2269, 1996 [9] U.M. Jow, M. Ghovanloo,”Modeling and Optimization of Printed Spiral Coils in Air, Saline, and Muscle Tissue Environments”, IEEE Transactions on Biomedical Circuits and Systems, Vol. 3, No. 5, October 2009. [10] L. Rindorf L. Lading, and O. Breinbjerg, “Resonantly coupled antennas for passive sensors,” Proc. IEEE Sensors, Oct. 26–29, 2008, pp. 1611–1614. [11] K. Fotopoulou, B.W. Flynn, “Wireless Power Transfer in Loosely Coupled Links: Coil Misalignment Model”, IEEE Transactions on Magnetics, Vol. 47, No. 2, February 2011, pp. 416-430. [12] K. Van Schuylenbergh, R. Puers, “Inductive Powering”, Chapter 2, in book: “Basic Theory and Application to Biomedical Systems”, Springer Verlag, ISBN: 978-90-481-2411-4, 2009 [13] A. Karalis, J.D. Joannopoulos, M. Soljacic, “Efficient wireless non-radiative mid-range energy transfer”, Annals of Physics 323 (2008), pp. 34-48. [14] A. Kurs, A. Karalis, R. Moffatt, J.D. Joannopoulos, P. Fisher, M. Soljačić, "Wireless power transfer via strongly coupled magnetic resonances", Science 317 (5834), July 2008, pp.83–86. [15] M. Dionigi, Alessandra Costanzo, and M. Mongiardo, “Network Methods for Analysis and Design of Resonant Wireless Power Transfer Systems”, in book “Wireless Power Transfer - Principles and Engineering Explorations”, K.Y. Kim (Editor), Chapter 4, ISBN: 978-953-307-874-8. [16] A. K. RamRakhyani, S. Mirabbasi, M. Chiao, “Design and Optimization of Resonance-Based Efficient Wireless Power Delivery Systems for Biomedical Implants”, IEEE Transactions on Biomedical Circuits and Systems, VoL. 5, No. 1, February 2011. [17] A. Marinescu, I. Dumbravă, “Coupling Factor of Planar Power Coils Used in Contactless Power Transfer”, Proceeding of the 9th International Symposium Advanced Topics in Electrical Engineering – ATEE’15, Bucharest,7 - 9 May 2015. [18] F .A. Duck, Ch. 6, in book, “Physical Properties of Tissue”, Academic Press Ltd, ISBN 0-12-222800-6, 1990

[19] ICNIRP, “Exposure to high frequency electromagnetic fields, biological effects and health consequences (100 kHz – 300 GHz)”, ISBN 978-3-934994-10-2, 2009. [20] A. Marinescu, “EMF Issues Related to Inductive Contactless Power Transfer”, Proceeding of 5th International Conference on Modern Power Systems MPS 2013, May 2013, Cluj-Napoca, Romania.

VI. BIOGRAPHIES Andrei Marinescu was born in 1940 in Craiova and

received the Dipl. Eng. and PhD degrees from the University Politehnica of Bucharest in 1961 and 1977, respectively. From 1961 to 1968 he was with Central Laboratory of Electroputere Company as testing engineer and from 1966 he was part-time Professor for Electrical Engineering by Craiova University (from 2000 Honorary Professor). From 1968 to 1989 he was the Head of High Voltage Laboratory and from 1990 to 2008 Research Manager of ICMET Institute. He is author of over 100 technical papers, and 5 books. DAAD Visiting Scientist at Karlsruhe University and NATO Fellowship at University of Patras. He is full member of ASTR (Romanian Technical Science Academy), founder and Chairman of ACER (Romanian EMC Association), founder of IEEE EMC Romanian Chapter and in 2002 was granted with the “Traian Vuia” Award of Romanian Academy. Since 2008 he is Senior Technical Adviser and Chairman of Research Council in the same Institute. His research interests include High Voltage measuring and testing technology including fiber optic current sensors, contactless power transfer and electromagnetic compatibility. From 2011 he is partially retired from ICMET. He is IEEE Senior Member.

Mihai Tarata was born in 1953, PhD in Electronics, Chair and Professor Medical Informatics & Biostatistics Dept., The University of Medicine and Pharmacy of Craiova, Romania. Visiting Professor: Iowa State University, Ames, Iowa, USA, Universitaet der Bundeswehr, Munchen, Germany, University of Lisbon, Lisbon, Portugal, Catholic University of Leuven, Belgium, University of Patras, Greece, University of Leeds, England. 40 publications in journals and proceedings with peer review out of a total of 87 published in extenso. Member of International Society of Electrophysiology and Kinesiology, International Biometric Society, IEEE Engineering in Medicine and Biology Society, Romanian Academic Society, International Society of Bioelectromagnetism. Interests: Electronics, Neuromuscular Fatigue, Human adaptive behavior, Signal & image processing. Hobby: Radioamateurism YO7LHN.

Mihai Iordache was born on November 19, 1944. He received the M.S. and Ph.D. degrees in Electrical Engineering from the University Politehnica of Bucharest, Romania, in 1967 and 1977, respectively. From 1993 he is a Full Professor in the Electrical Department, University Politehnica of Bucharest, where he is working in the Electrical Engineering Fundamentals, Circuit Theory – methods, computing techniques, algorithms, optimization techniques, parameter estimations, and software tools for analysis and simulation, Graph Theory, Wireless Power Transfer Systems, and Topological Analysis. He is the author or coauthor of more than 300 journal papers (two of them published in Analog Integrated Circuits and Signal Processing, and in International Journal of Bifurcation and Chaos), and 30 books and monographs. From 1997 he is

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Doctoral Advisor at the University Politehnica of Bucharest. He was the recipient of the 2000 Romanian Academy Award and of the 2004 Romania Engineering Association. He is IEEE member.

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Abstract - This project’s purpose is to develop multiple devices for the medical rehabilitation of the hand. The authors present different aspects and experiments and the technological aspects. We have made this paper to present to you means to recovery for a person which has suffered upper arm injuries. With the purpose of regaining the mobility of the damaged parts, we’ve constructed these devices:

• the vibration structure; • the cam electromechanical system (which we are still

working on); • the string system.

Index Terms - rehabilitation, vibration structure, electromechanical system, string system, hand.

I. INTRODUCTION Medical recovery is a subject in which we, as

humans, can improve our medical condition by inventing machines, remedies and researching new ways of approaching the recovery procedures in order to help us to perform like a normal person after an illness or unfortunate accident.

This field is one of great importance and we truly need to pay attention to it, as it may help a lot of people who are in pain or who are disabled by some illness, wound or trauma.

However, this subject must be approached step by step, inventing a recovery means for every disease and condition. As such, we as humans must develop smart ways of healing certain parts of our bodies, using technology and basically any means at our disposal. -maintaining or increasing of the functional level in miscellaneous pathologies, focused on structures of the locomotor system.

Medical rehabilitation is a special clinic-therapeutic section which follows:

• maintaining or increasing the functional level in miscellaneous pathologies, focused on the structures of the locomotor system.

• the realization of some facilitators, internal or external, with the help of which the patient can conduct activity on a normal basis.

II. THE ANATOMYCAL AND PHYSIOLOGICAL DESCRIPTION OF THE

HAND AND FINGER Because our research project is concentrated

on the hand and finger medical rehabilitation we present an anatomical description of the hand.

Fig. 1. The structure of the hand.

In the recovery process we aim to improve the

state of the following bones, which contribute to the movement of the finger: the carp (a), the metacarp (b), the phalanges (c) and the seismodal bones.

The skeleton of the hand consist of 27 (see Fig. 1) bones arranged in three groups:

a. The Carp consists of eight carpapal bones and is the proximal segment of skeleton hand. The eight carpal bones fit together to form an arched bone structure.

b. The Metacarp is the primarily long bone of the hand. It consists of metacarpal bones, numbered from I-V from lateral to medial.

c. The Phalanges are the bones of the fingers and form the distal segment of the hand. Except the thumb, which has only two phalanges, all other fingers have three: proximal phalanx, medial phalanx and distal phalanx. • The Proximal phalanges are the largest and have

the characteristics of a long bone, with head, body and base (proximal segment).

• The Medial phalanges have the same characteristics as the proximal ones, but it is smaller.

• The Distal phalanges are flat on their palmar surface, small, and with a roughened, elevated

Devices for medical rehabilitation *Cosma Radu, **Mosessohn Vlad, ***Mihaila Alin

National Institute for Research and Development in Electrical Engineering (INCDIE ICPE-CA), Splaiul Unirii, No. 313, District 3, 030138, Bucharest, Romania,

*radual99@yahoo.com, **vlad_mose@yahoo.com, ***mihaila.alin99@yahoo.com

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surface of horseshoe form on the palmar surface, supporting the finger pulp. Metals that can be used to produce microwires include copper, silver, gold, platinum, iridium and various alloy compositions. We used copper and iron-boron-silicon for the experiments.

Fig. 2. The structure of the finger.

The Wrists

The wrists are interphalangeal joints of the

hand. • The thumb has only one interphalangeal joint,

while the other fingers have 2. • The joints are between the head and the base

of the phalanges. • Joint capsules are strengthened by 2 collateral

ligaments and palmar ligaments. The Muscles

The muscles acting for the movement of the

fingers are not only in the hand, but in the forearm too. 1. Forearm muscles

• The forearm muscles are flexor muscles of the anterior region of the forearm muscles act as flexors of the hand, wrist and fingers.

• They are divided into:

A. superficial flexor muscles B. deep flexor muscles C. superficial extensor muscles D. deep extensor muscles

2. Hand muscles At the hand level, the muscles are grouped in

lateral muscles (thenar eminence), medial muscles (hipothenar eminence), and between them are the lombrical muscles and the interosseous muscles.

This project is focalized on the devices for hand and finger medical rehabilitation and specific procedures that can help revitalize the upper limb.

III. ELECTROMECHANICAL STRUCTURES AND DEVICES FOR

MEDICAL REHABILITATION

A. A hand and fingers electromechanical device based on vibrations

Fig. 3. The vibration system with solenoid actuators.

The electromagnet(Fig.3) which is feeded in

AC (alternative current) produces vibrations in the vibroplate (coupled with the string of the mechanical vibrations).

The characteristics of the device: Voltage: 220V, frequency: 50Hz, number of turns of electromagnet coils: 2500 (with the diameter of conductor: 0.2 mm).

In Fig. 5 is presented the use mode, in the case of a procedure for wrist of hand rehabilitation. Specific to the carp and metacarp (see Fig.1 and 2).

Fig. 4. The vibration device.

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Fig. 5. The utilization mode.

We designed this device for the use of those

who have broken bones and articulations, because the vibrations generated be this device help the broken parts recover by providing the necessary help for them to get back together. Also, the vibration helps the fixation of Calcium in our bones, which furthers the device’s target.

The metal plate is also designed with only one attachment point to the main device, to facilitate higher vibrations the higher that the amplitude gets. As such, a patient can be exposed to a diminished or to an increased vibration, depending on their needs and the doctor’s recommendation.

The device works with the wrist, the fingers and the base of the hand (the carp). A patient must simply place the affected area on the metal plate, in the area most indicated for the recommended vibration intensity, and turn it on. The duration of the exercise depends on each patient, and it must be repeated at least every day.

“Localized vibration therapy has a stimulating

effect on small groups of muscles. With regards to improvement of bone density, it has been suggested that vibration therapy may induce nuclei inside the cells to trigger the release of osteoblasts, which are needed to build bone.”

-Healthline.com-

B. The cam electromechanical system for finger rehabilitation

The system includes a synchronous motor which drives a spindle with misaligned elements. The structure of this device is presented in Fig.6. The eccentric elements are presented in Fig.7. The kinetic scheme is shown in Fig.8.

Fig. 6. The structure of the cam electromechanical device.

This system is good for medical rehabilitation

because each finger is trained and so the finger joints realize normal movements which help recover the finger.

Fig. 7. The misaligned elements.

We have determined the best dimensions for

these elements by various experiments. Being actuated by the spinning drive, the elements move the patient’s finger without needing him to use any force. This is an extremely important characteristic because more patients have difficulties in moving their fingers and so they can exercise with them. This exercise is benefic for them because, by moving the finger, it tends to get used to the movement and later it may be able to move by itself without any help from a device.

Fig.8 The kinetic scheme of the device.

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The drive of this device (which is not finalized) is possible with the synchronous micromotor with microreducer, showed in Fig.9.

Fig. 9. Synchronous micromotor with microreducer.

This device is not currently finalized, although

we are working hard to get it done as soon as possible, as we believe that it is very important for regaining mobility in the immobile fingers.

C. Flexion device for finger medical rehabilitation

Fig. 10. Flexion device for finger medical rehabilitation.

This device(Fig.10) is useful for those with

impaired but existent mobility in their fingers, enough to pull the resorts. The device has a meter based on the force with which the patient pulls, and at 50N, the ideal force for a recovered person, three LED’s light up.

The utilization mode: 1. Put your fingers into the rings; 2. The LEDs light when the pulling force reach 100 N; 3. Make some exercises for 1 hour per day by pulling the resorts;

4. Write down the progress. Below, in table II and III, are the normal

parameters extracted from our experiments on healthy patients. We measured their pulling force by using a dynamometer. This data is useful in determining the pull force a patient should reach. Of course, this force is also established judging the gravity of the injury. TABLE II. The normal parameters determined on healthy patients – left hand. Patient name

Left hand - pulling force [kgf] little

finger ring

finger middle finger

pointer finger thumb

C. R. 1.25 2.35 3.4 3.45 4. M. A. 1 1.1 1.7 2.15 3.2 M. V. 1.8 2.3 3.6 4.6 5k I. M. 2.5 3 3.1 4.1 2.1 L. A. 1.5 2.5 3 2.9 2 G. S. 1.9 1.7 2.4 2.3 3 S. T. 2.5 2.35 3.65 4.4 4.65 F. A.

(female) 1.95 2.1 3.5 3.8 4.5

I. C. 2.6 2.7 3.2 3.3 3.7 V. M.

(female) 1.35 1.6 2.25 2.9 5.1

R. S. (female) 1.5 1.5 2.4 2.15 4.1

L. A. (female) 1 0.8 1.5 1.1 1.5

Average 1.73 1.88 2.8 3.45 3.63

TABLE III. The normal parameters determined on healthy patients – right hand.

Patient name

Right hand - pulling force [kgf]

little finger

ring finger

middle finger

pointer finger thumb

C. R. 1.55 2.6 3.8 3.9 4.2 M. A. 1.4 2 3.1 4 2.2 M. V. 2.1 2.25 4.35 5.1 4.8 I. M. 2.2 2.5 3.2 3.5 3.1 L. A. 2.3 2.15 3.1 3.4 3.5 G. S. 1.6 1.65 2.1 2.6 2.2 S. T. 2.1 2.1 2.95 2.9 2.2 F. A.

(female) 2.8 2.1 3.7 3.6 4

I. C. 2.9 2.75 4.2 4.1 6.2 V. M.

(female) 1.35 1.75 2.65 2.85 4.1

R. S. (female) 2.1 1.4 2.55 2.3 3

L. A. (female) 1 1 1.3 1.1 1

Average 1.95 2.02 3.08 3.57 3.38

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IV. CONCLUSIONS This project’s purpose is to bring the damaged

upper limb to parameters close of identical to the normal finger. Our project is still in progress, and we are working hard at the cam electromechanical system, hoping for it to be ready as soon as possible. . We have made measurements for it and we are close to its finalization. We are also working on improving the already finished devices.

V. ACKNOWLEDGMENT We couldn’t possibly make this project without the help

and guidance of our coordinator Mircea Ignat and the moral support from our families. They all have been willing to help us whenever they could, from reviewing our project to testing the devices and realize that they really were functioning properly. Thank you so much for supporting us!

VI. REFERENCES [1] Nica S. ,”Recuperarea medicala. Curs” Universitatea de Medicina si Farmacie, Bucuresti, 1996. [2] Vaughan Ch., Davis B. O’Connor, “Dynamics of Human Gait”, Kiboho Publishers, cape Town, South Africa, 1995. [3] Mantea C., Manual fizica clasa a IX-a. Mecanica, Ed.All, 2006. [4] Voinea R.,Voiculescu D., Ceausu V., ”Mecanica”, Ed. Didactica si pedagogica, Bucuresti, 1975. [5]http://www.webmd.com/rheumatoid-arthritis/an-overview-of-rheumatic-diseases. [6]http://www.webmd.com/rheumatoid-arthritis/guide/hand-and-finger-ra. [7] http://www.healthline.com/health/vibration-therapy#2.

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Abstract - Landmines kill or injure thousands of people every year. This is affecting society on both psychological and economical sides. This article will focus on a prototype which will simulate one viable solution that could solve the problem of landmines in various locations around the globe. The prototype was developed by a team of 8 students within the Robotics First Semester Project at Aalborg University, Denmark while assisted by a supervisor. Therefore, the article is based on the actual report written for the project (report itself available upon request). Some current methods and technologies will also be summary described as the proposed solution for the landmine problem will rely on a combination of two devices which are known to be effective in landmine detection. Index Terms - landmines, solution, safety, automation, robot, map, precision, hardware, operation mode, software.

I. INTRODUCTION Landmines were very popular as weapons

through history, especially in major conflicts. Having an important factor in warfare strategy, the development and production of landmines escalated in the Second World War, only the Soviet Union alone plating more than 220 million landmines in the war fields [1].

Landmines and improvised explosive devices pose a great danger for civilians living in current or former war zones. Around 79% of the recorded casualties caused by landmines are reported to be civilians, 46% of them being children [2].

The landmine problem has been acknowledged worldwide, which has resulted in the creation of many organizations, initiatives and technologies in order to reduce to zero the number of landmine caused victims. One initiative to be mentioned is “The mine ban treaty”, created in 1997 and signed by 80% of the world’s countries in order to stop the production and storage of landmines [3].

II. CURRENT METHODS AND TECHNOLOGIES FOR LANDMINE

DETECTION Great efforts were made in order to develop an

optimal solution for detection and disposal of landmines. Different solutions coming from a lot

of different fields are being developed to eliminate the landmine problem.

In what follows, two of the current methods and technologies, which were found fit for the proposed solution, are to be described.

The most popular method to detect landmines is using the metal detector. Usually, the metal detector needs a human operator who will carry the device along the desired area to be landmine free. After detection, the operator has to disable the mine manually. This method is very dangerous as some landmines do not contain metal at all [4].

A method which could come in aid for the metal detector’s inability to sense plastic made landmines is the ground penetrating radar (GPR). The GPR is an old technology which was discovered around 1920, but no viable progress regarding the detection of landmines was made in order to make it a reliable sensor for this purpose. The main reason GPR is not a popular device to detect landmines is the way different soil types are influencing the readings. Anyway, it is expected that in the next years, GPR will become an optimal device for landmine detection [5].

Fig. 1. Ground Penetration Radar [6]

What concerns regarding the above mentioned

technologies is that they need a human operator. The proposed robotic solution which will be described later in this article is eliminating the

Autonomous Landmine Detection Robot *Ioan-Matei Sarivan

Aalborg University (AAU), Fredrik Bajers Vej 5, 9220 Aalborg Øst, Denmark, *isariv15@student.aau.dk, s.i.matei96@gmail.com

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human operator in order to increase the overall safety.

III. PROPOSED ROBOTIC SOLUTION FOR LANDMINE DETECTION

The proposed solution will reduce some of the problems encountered with the metal detector and ground penetrating radar like the need of a human operator. Also, being a robotic solution, a large area can be covered with no time wasted and with minimal human effort. The probability of injury during the detection will be reduced as well.

The proposed robotic solution is shaped by a hovercraft equipped with a metal detection device and a ground penetrating radar (Fig. 1). These two combined are expected to generate precise detection reports and a very low amount of false positives in the case of anti-personnel landmines.

Fig. 2. Schematic representation of the mine detector

hovercraft equipped with Ground Penetrating Radar (GPR) and Metal Detector. The other main components can also

be observed

In order to implement the proposed solution, Renegade IQ hovercraft from the Renegade Hovercraft Company would be a good choice for the robot’s base. IQ is able to carry around 209 kg of cargo and it has a range of 241 km with a full fuel tank [7].

Besides the detection devices, the Renegade hovercraft will be equipped with numerous sensors and miscellaneous devices like GPS, gyro sensor, proximity sensor etc. to make the vehicle as autonomous as possible.

The hovercraft is also an optimal solution because it will not fire the landmines as the pressure applied on the landmine’s trigger plate is very low.

Another advantage of the hovercraft is its segmented skirt. This means that in case of a triggered landmine, the damaged segment can be replaced.

The main processing unit of the mine-detection robot will be a computer which will receive data from the sensors and control the hovercraft in real time. A remote computer can also be used in order to monitor the robot, make

modifications in its processes, view a map with the detected landmines etc.

The proposed solution is addressed to humanitarian organisations involved in the combat with landmines and regular people (farmers) who own land infected with antipersonnel mines. In order to make it highly accessible, the robot will be available to rent for individuals who may only need this kind of solution once.

The proposed solution is not solving the disposal problem which in the end has to be handled by specially trained people.

IV. MINE-DETECTOR PROTOTYPE In order to demonstrate the proposed final

solution, a prototype was developed using all the components which are included in the Turtlebot 2 kit [8]. This section will be divided in three subsections in which the hardware component, operation mode and the software component will be treated separately.

A. Hardware The hardware of the Turtlebot 2 is composed

of the Kobuki base, Asus Xtion PRO Live (Kinect like device) and Asus X200M Notebook (Figure 3).

The Kobuki base is, as the name states, the base of the Turtlebot 2 which is ensuring the movement and the basic functions of the robot. Besides motors and other necessary components, the base holds IR sensors located on the bottom, gyro sensor and rotary encoders. These sensors are ensuring some basic functionalities of the prototype like mine detection simulation, orientation in space and measurement of covered distance.

A crucial component of the prototype is the Kinect like device Asus Xtion PRO Live. Together with the designated software, Asus Xtion is possible to generate a 3D modelling of the surroundings in which the robot is placed. This comes in very handy when dealing with obstacles.

The “brain” of the prototype is an Asus X200M Notebook in which the software component is stored and executed. Therefore, the notebook is used as an operation unit for the Turtlebot.

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Fig. 3. Kobuki Turtlebot 2 equipped with ASUS Xtion PRO Live and Asus X200M Notebook used to demonstrate the

mine-detector robotic solution

B. Operation mode It is very simple to understand how the

prototype works. This is why the basics of the prototype’s operation mode will be implemented in the proposed solution.

To simulate a minefield with obstacles, plastic parallelepipeds with dimensions of 15x15x1 cm were used to represent landmines and cylinders with the diameter of 30 cm and height of 50 cm were used to represent obstacles along the minefield (Figure 4).

Fig. 4. The mine detection robot while operating. A

"landmine" and an "obstacle" can be observed

The size of the detected minefield can be variable and it is required as user input every time a new minefield is required to be scanned.

Fig. 5. Movement of the robot across the minefield

After giving the required input (width and

length of the minefield and the location of the robot relating to the centre of the minefield: right or left), the robot will begin scanning the minefield in a zigzag like manner, insuring that each centimetre of the field was properly checked for landmines.

While the robot is moving across the minefield, it will generate a map on which the mines and obstacles will be displayed. In order to detect the mines, the robot is using the IR depth sensors located on the bottom of the Kobuki base.

The sensors are constantly measuring the distance between them and the ground. The moment the value received from the sensors is considerably bigger; it means that a mine was detected. The detection method is illustrated in Figure 6.

Fig. 6. Detection method

The distance covered by the robot is constantly

measured by the rotary encoders. These sensors provide the necessary data in order to know where the robot is located in relation to the point from which began scanning the minefield.

To determine the orientation of the robot for making 90 degrees turns, the gyro sensor is used.

In order to generate the map and to detect the obstacles located on the minefield, the robot is using the Kinect sensor.

In case of detected mine, a marker will be added on the generated map and the robot will

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proceed to move around it. This process will be further described in the “Software” section.

C. Software The software component is insuring that the

robot will execute all the actions described in the “Operation mode” section. There is no possibility for hardware to work without software and there is no sense for software without hardware.

The software it is stored on the Asus notebook which is running a version of Linux. With Linux is installed ROS (Robot Operating Software) which makes possible low-level control and complex operation of multiple sensors and motors at the same time [9].

One key feature of the prototype’s software made possible by using ROS is the ability to run multiple programs at the same time which can communicate between each other using a publisher-subscriber pattern [10]. These programs are also known as nodes.

The prototype’s software contain multiple nodes, each having different purposes like receiving data from a sensor and processing the data received from other nodes in order to generate an output. The nodes are communicating between each other by publishing or subscribing to a certain topic. This ensures the independence of the nodes: if the node which is publishing on a topic stops, the node which is subscribed to that topic will continue its execution.

With the independence of the nodes between each other comes another great advantage of using ROS in order to program the prototype. The nodes can be programmed in different programming languages like C++ or Python. Python, being a scripted programming language therefore more accessible, is used to program the nodes which are receiving data from the prototype’s sensors because they don’t require a certain speed for execution. C++ being a compiled programming language, therefore much faster to execute, is used to program the nodes which are processing the data received from other sensors as a small execution time is required in order to make the robot work properly at this stage [11], [12].

In Fig. 7 the data flow between different hardware components and different ROS nodes is represented. As it can be observed, the nodes which are handling data from sensors without complex processing are programmed in Python, while the node which is receiving data from all the other nodes and generates input for motors is

programmed in C++. The arrows in the figure represent both the sense in which the data is travelling and the topics on which data is published (the topics have the same name as the subscribers in the prototype’s case). In other words, the “Detection” node, for example, is actually subscribed to the topic where the IR Depth Sensors are publishing.

Fig. 7. Data flow between hardware and software

components

In order to get a better understanding of how the software works the functionality of each node will be individually explained.

The detection of the parallelepipeds which simulate the landmines is made possible by the “Detection” node. This node is receiving data constantly from the IR Depth Sensors and it converts it in a Boolean value which then will be published on the topic to which the “Processor” node is subscribed. The value from the sensors is increasing as the distance between them and the reflective surface gets smaller. During experiments was observed that if a “mine” is placed under the prototype’s base, the value received from the sensors will increase with around 200 units. In order to eliminate any variations caused by different types of surfaces, the node is computing the difference between the current value and the previous value at the moment of measurement. If the difference is bigger than 200, it means that a mine was detected and will publish the value ‘1’ as seen in Fig. 8.

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Fig. 8. The values received from the IR Depth Sensors are

converted into one Boolean value For navigation, the robot is using data received

from the rotary encoders and gyro sensors. Using the rotary encoders, an approximate

value of the distance covered is computed. The “Covered Distance” node is processing the data from the rotary encoders about the same way as the “Detection” node: by computing the difference between the previous and current value. Afterwards, the obtained values are added up until a certain value is obtained while the robot is moving. After a number of experiments, it was determined that the value 3800 (obtained after making consecutive additions with the computed differences) is equivalent with a covered distance of around 35 cm. The down come of this method is that the speed of the robot has to be low in order to determine the covered distance precisely. In Fig. 9 is displayed the data received from the rotary encoders.

Fig. 9. Console data displayed by the “Encoders” node For making 90 degrees turns as described in

the “Operation Mode” section, the “Orientation”

node is gathering data from the gyro sensor and then it publishes it immediately for the “Processor” node to receive. The reason why this node doesn’t include any complex processing is because the raw data from the sensors is used. In order to make turns, the orientation’s quaternion coordinates relating to the minefield’s cardinal points are stored. To head right across the minefield, the robot will have to head east (relating to minefield’s cardinal points). To do that, the robot will turn right or left until the current quaternion coordinates received from the gyro sensor will be the same as the set which is stored in memory at the beginning of the scan.

Fig. 10. The "Orientation" node is receiving the ‘z’ and ‘w’

quaternion coordinates of the robot's orientation while turning

The last Python node, “Obstacle”, is

processing the data received from the Kinect in order to determinate if there is an obstacle in front of the mine detector prototype. Again, this node is similar with the “Detection” one as it converts the value of the distance between the sensor and the first reflectance surface into a Boolean value. If the distance between the robot and the obstacle is smaller than 15 cm, the robot will stop and begin avoidance manoeuvres.

Fig. 11. The "Obstacle" node is publishing a Boolean value:

1 if obstacle is being detected, 0 if the path is clear

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The most important node is the C++ “Processor” node which is receiving the data from all the other nodes generating in the end output for the motors making the robot move accordingly to the environment configuration and the mine-detector algorithm.

After initializing the “Processor” by entering the width and length of the minefield, the robot will enter in a loop, moving the robot as described in the “Operation Mode” section depending whether or not a landmine or an obstacle is encountered.

While the robot is moving, a map is generated on which the detected landmines and obstacles are displayed. This is possible using the “rviz” tool which is available inside the Robot Operating System (ROS). The map is generated using the Kinect sensor mounted on the Turtlebot.

Fig. 12. “Rviz” generated map

In Fig. 12, the detected landmines can be

observed (marked with red squares), while the obstacles are marked with the colour yellow. The blue and indigo colouring around the obstacles represent how the prototype is affected as it gets closer to the obstacles (indigo marks the safe zone and blue means that the robot has to slow down).

While the obstacles are placed on map automatically using the “rviz” tool, for the red markers to be placed a C++ node and a Python node are used together with the “Detection” node.

The Python node named “Coordinates” is getting the Cartesian position and the orientation of the robot inside “rviz”. Depending on these coordinates, a marker will be placed on the map in the moment of detection when the “Detection” node will publish the value ‘1’.

The C++ node, named “Basic shapes” is processing data received from the “Coordinates” and “Detection” node and is publishing the information needed for “rviz” to place the red mark in the designated place. The mark is placed on the map only if a mine was detected.

To place the mark in the right spot on the map, the orientation of the robot at the moment of detection is required. In Fig. 13, are displayed the orientation quaternion coordinates which are important for the computations which are taking place in the “Basic shapes” node.

Fig. 13. The ‘z’ and ‘w’ quaternion coordinates depending

on the robot's orientation. The corresponding angle and cardinal points are also displayed

The orientation of the robot is needed to know

where the marker will be placed referring to the robot (north, west, east or south). Therefore, if:

(1) and

(2) will mean that the robot is heading east relating to the map in “rviz” so the detected mine has to be in east relating to the robot’s position. It is also known that the robot is only turning 90 degrees, not less or more, the orientation angle in this case is θ = 0 and the rotation matrix is the identity matrix:

(3) In case if:

(4)

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(5) the robot is heading north with the orientation angle being θ=90˚ and the following rotation matrix:

(6) The same procedure is applied when the robot

is heading west (the rotation matrix will be R2 for θ=180˚) and south (the rotation matrix will be R3 for θ=270˚).

Now that the rotation matrix is known for the current orientation of the robot, the next step is to translate the landmine marker in the direction in which the robot prototype is heading. It is known that the distance from the centre of the material prototype to the centre of the material “landmine” is around 0.2 meters in the moment of detection, so the landmine will be translated with 0.2 meters from the centre of the robot in the direction the robot is heading inside “rviz”.

To do this, the position vector of the landmine relating to the centre of the robot:

(7) will be multiplied with the respective rotation matrix. Afterwards, the current Cartesian coordinates of the robot inside “rviz” will be added as well in order to obtain the precise location of the landmine marker on the map:

(8) where i [0; 3] and x and y are the current coordinates of the Turtlebot inside “rviz”.

In Fig. 14, the console output of the “Detection”, “Coordinates” and “Basic shapes” nodes at the moment of detection can be observed. The marker will be placed on map only in the moment when the “Detection” node will publish the value ‘1’. “Case: 1” states that the robot is heading north (0 for east, 2 for west and 3 for south) and the coordinates where the marker will be placed are x=0 and y=0.3.

Fig. 14. Console output from "Detection", "Coordinates"

and "Basic shapes" nodes In order to have a better view over the inter-

node communication, Robot Operating System has available useful tool, named “rqt_graph”, which is generating a graphical representation of the relation between the active operating nodes. This tool was also found valuable during the debugging processes, as it shows if a certain node is receiving data from another node or not (Fig. 15).

Fig. 15. The "Detection", "Coordinates" and "Basic Shapes"

nodes are displayed in "rqt_graph"

V. OPERATING THE MINE-DETECTOR ROBOT PROTOTYPE

An important feature of the prototype is the low complexity of the user interface as there are only a few steps needed to be followed in order to start up the robot.

The user only has to input the length and width of the minefield and the location where the mine-detector robot is placed (left or right), in the terminal window displayed in Fig. 16.

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Fig. 16. Main terminal window of the prototype's

software While scanning the minefield, the user is

constantly kept informed regarding the robot’s current status as seen in Fig. 17, 18, 19 and 20.

Figure 17: The robot has encountered a mine and is now proceeding to go around it. The displayed values are the

quaternion coordinates of the goal orientation and the current quaternion coordinates. The angular speed of the

robot is 0.4 radians per second.

Fig. 18: The robot is travelling across the width of the

minefield. It has completed 105 cm of the 140 cm which the robot has to travel until the edge of the minefield. The robot is moving with a speed of 0.25 meters per second.

Fig. 19. The robot is avoiding a "landmine"

Fig. 20. The robot has finished scanning the landmine and

now it is waiting to be turned off. All the detected landmines and obstacles are displayed on the generated

map (Fig. 12)

VI. ERRORS DURING OPERATION While operating, a robot has to be precise in

order to be considered as a viable solution to a problem. This is applying for the mine-scanning robot as well.

During experiments with the prototype, some errors where observed which were not possible to solve at this stage of the project.

The following sources for error have been discovered and their immediate effect as well: • Slow reaction of the sensors is causing the

robot to not turn 90˚ exactly; • Measurement errors of the length are causing

the prototype to go out of the scanned minefield or not reach the edge of the minefield;

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• Variations of external light may cause the robot to not detect the landmine models every time.

Future work on the prototype is expected to eliminate this kind of errors.

VII. CONCLUSIONS The main purpose of this project is to come

with a robotic solution for the landmine problem which is encountered in former and current war zones. This solution implies that no human being is put at danger while a minefield is being scanned for landmines.

Using the Turtlebot 2 kit, a prototype was successfully developed in order to demonstrate the operation mode of the proposed solution described in Section III.

It is hoped that using this kind of robots, human casualties caused by landmines will be reduced by simplifying the task of landmine disposal. Even though the operation mode of the proposed solution is successfully demonstrated using the Turtlebot 2, the actual solution will require more advanced equipment in order to detect landmines in a real life scenario.

VIII. ACKNOWLEDGMENT Simon Bøgh, Assistant Professor and Supervisor at

Aalborg University, Denmark. Group supervisor of the development of the Robotics first semester project “Autonomous Landmine Detection Robot”;

Andreas Flem Norman, Robotics Student at Aalborg University. Group member during the Robotics first semester project;

Rasmus Vedel Nonboe Kobborg, Robotics Student at Aalborg University. Group member during the Robotics first semester project;

Daniel Kjær Bonde Fischer, Robotics Student at Aalborg University. Group member during the Robotics first semester project;

Jakob Kristiansen, Robotics Student at Aalborg University. Group member during the Robotics first semester project;

Sebestyen Nagy, Robotics Student at Aalborg University. Group member during the Robotics first semester project;

Marius Frilund Hensel, Robotics Student at Aalborg University. Group member during the Robotics first semester project;

Casper Benjamin Sloth Mariager, Robotics Student at Aalborg University. Group member during the Robotics first semester project.

IX. REFERENCES [1] Rae McGrath, “Landmines and Unexploded Ordnance: A Resource Book”, Pluto Press, April 2000, p. 6. [2] “Landmine Monitor 2012”, Landmine and Cluster Munition Monitor, November 2012.

[3] “Why the ban?”, www.icbl.org/en-gb/problem/why-the-ban.aspx. [4] Robert Keeley, “Understanding Landmines and Mine Action”, September 2003, http://web.mit.edu/demining/assignments/understanding-landmines.pdf. [5] Jacqueline MacDonald, J.R. Lockwood, “Alternatives for Landmine Detection”, RAND Corporation, Santa Monica, 2003, www.rand.org/pubs/monograph_reports/MR1608.html. [6]www.usradar.com/images/system/quantum-quarterview-large.png. [7] “Renegade IQ Hovercraft” www.renegadehovercraft.com/renegade-turnkey-iq.html. [8] General presentation of the Turtlebot 2 robot, www.robotnikstore.com/robotnik/5121532/turtlebot-2.html. [9] “Introduction to ROS”, http://wiki.ros.org/ROS/Introduction. [10] “Writing a Simple Publisher and Subscriber”, http://wiki.ros.org/ROS/Tutorials/WritingPublisherSubscriber(c%2B%2B). [11] “General Python FAQ”, https://docs.python.org/2/faq/general.html#what-is-python-good-for. [12] “A benchmark about speed of programming languages”, http://nileshgr.com/2012/08/25/a-benchmark-about-speed-of-programming-languages.

X. BIOGRAPHY Ioan-Matei Sarivan is currently a second semester

Robotics student at Aalborg University in Aalborg, Denmark. Between the main fields of this study are Mathematics (linear algebra, calculus etc.), Programming, Robot Mechanics etc.

Starting with September 2013, Matei became a member of the Excellency Centre for Young Olympics (ECYO), which is part of the Micro and Nanoelectrotechnologies department at the Romanian Institute of R&D in Electrical Engineering, under the coordination of Ph.D. Eng. Mircea Ignat.

As a member of ECYO previous publications are to be mentioned: • “The Robots and Measuring Instruments”, published in

the “Bulleting of Micro and Nanoelectrotechnologies”-December 2013, vol. IV, no. 3-4;

• “Line-Follower”, published in the “Bulleting of Micro and Nanoelectrotechnologies”- December 2014, vol. V, no. 3-4.

The research preoccupation include: the synchronous generators and the high speed electric machines. He is member of IEEE.

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Abstract - The paper presents general aspects of the eye. There are described theoretical aspects about the anatomy, physiology, pathology and the movement of the eye. Index Terms – eye movement, eye anatomy, microelectromechanical drive.

I. INTRODUCTION Almost all the information that comes from the

outside world into the brain depends on vision. The eye is one of the most complex organs in the entire body. Among its functions, one could mention the perception of size and texture of an object even before entering in contact with it or the perception of the distance at which it is situated.

It is also presented the intention to create a bionic system that resembles the eyeball, in order to obtain an electro-mechanical unconventional drive upon a spherical object, with different technical appliances.

II. ANATOMY AND PHISIOLOGY The eye is a slightly asymmetrical globe, about

an inch in diameter, although the average newborn’s eye is about 18 mm in diameter. It contains: - the cornea (fibrous tunic; transparent

membrane over the iris; focuses light entering the eye).

- the iris (connective tissue and smooth muscle fibers: circular and radial; organized in 3 layers: endothelium, stroma, epithelium; each pattern, color-determined by our melanin and lipochrome levels and indirectly by chromosomes 15 and 19; texture is unique and could be used as print).

- the pupil (allows the perception of light, controlled by the parasympathetic nervous system).

- the sclera (white opaque membrane; continues with the cornea; it’s an smooth optical surface and protects form drying the eye). [1] Behind the iris and pupil there is the

crystalline lens, whose function is to focus light on the back of the eye and form the image, upside down, on the retina.

Most of the eye is filled with a clear gel called the vitreous humour (about 80% of the eye’s volume; has 99% water in it). Light is projected through the pupil and the lens to the back of the eye, on the innermost layer of the eye. On the retina, there are two types of photosensitive cells that transform light into electrical impulses, i.e. rods and cones. Rods (about 120 - 130 million per eye) perceive only black and white light, suitable for night vision and dim light, whereas cones (6.5-7 million per eye) perceive colors and detailed images. There are 3 types of colors pigments: blue, green and red. Each have different wavelengths, in the above mentioned order from small (420 - 440 nm) to large (564 -580 nm). The impulses of both types of cells pass through the nerve-cell connectors and arrive at the optic nerve. [2]

Retina converts light into electrical impulses. Behind the eye, the optic nerve (C.N.II - Cranial Nerve II, sensorial nerve; about 1.1 million nerve cells) carries these impulses to the brain. It also is responsible for two important reflexes- light and accommodation. The macula is a small extra-sensitive area (great density of cones; 5.5 mm in diameter) within the retina that gives central vision. It is located in the centre of the retina and contains the fovea (1.5 mm in diameter; distinguishes the colors and the shades from one another), a small depression or pit at the centre of the macula that gives the clearest vision. [1]

Fig. 1. Range of the colors’ wavelengths.

Eye anatomy and movement *Andra-Maria Ciutac, **Carmen Gabriela Popa

National Institute for Research and Development in Electrical Engineering (INCDIE ICPE-CA), Splaiul Unirii, No. 313, District 3, 030138, Bucharest, Romania,

*andra123.maria@gmail.com, **carmengpopa@gmail.com

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Fig. 2. Anatomy of the eye.

III. EYE MOVEMENT AND 3D-VISION

Fig. 3. Extra-ocular muscles.

The eye globe is operated upon by six extra-

ocular muscles, four of them called rectus and the others oblique.

The rectus ones are responsible for moving the eye globe into the four cardinal directions: up, down, left and right, whereas the oblique muscles control the adjustment necessary for counteracting with head movement.

The field of vision is binocular, both eyes seeing at the same time, but having different perspectives. The images are superimposed at an angle of 120 degrees. This allows the form of 3D images (stereoscopic vision), as the eye perceives the same object under three different angles, without suffering any deformation. The left eye

perceives an object at an angle of 45 degrees; the images of both eyes superimpose at a right angle; the right eye completes the vision at the binocular arc at 120 degrees. [4]

Fig. 4. Formation of the 3D vision.

In go/no-go tasks, humans initiate manual

responses with average and minimum reaction times about 450ms and 250ms. Otherwise, the fastest eye movements can be initiated at a speed about 80-100ms. However, the fastest reliable eye movements are produced after 120ms.

There are four types of eye movements(Fig.5): saccades, smooth pursuit movements, vergence movements and vestibule-ocular movements.

Saccades movements are rapid and ballistic and they abruptly change the point of fixation. They can be elicited voluntarily (following a

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target, for instance) or involuntarily (while sleeping and when opining the eyes.)

Smooth pursuit movements are slow and help the eye keep a moving stimulus on the fovea. Such movements are under voluntary control. [5]

Fig.5 The specific eye movements.

Vergence movements align the fovea of each

eye with the targets located at different distances from the observer. This type of movement is disjunctive; they involve either a convergence or divergence of the lines of sight of each eye to see an object that is nearer or farther away.

Vestibulo-ocular movements stabilize the eyes relative to the external world. Therefore, it compensates with head movements and prevents the loss of an image. [6]

IV. PATOLOGY Myopia (Fig.6) is a refractive error of the eye

which appears when the light from a faraway object, focuses before it gets to the back of the eye. It is also called near-sightedness. This deficiency can be corrected with divergent lenses. [2]

Fig. 6. Comparison between normal vision and myopia. Hyperopia(Fig.7) is a refractive error of the

eye which appears when the light of an object does not focus by the time it reaches the retina. It is also called farsightedness. It can be corrected with convergent lenses.

Fig. 7. Comparison between hyperopia and normal vision.

In case of astigmatism(Fig.8) at least one of

the two (cornea or the lens) are not spherical enough. This is the most common refractive error.

Fig. 8. Comparison between normal vision and

astigmatism.

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All the above mentioned deficiencies can also be corrected surgically, with a photorefractive procedure-LASIK (laser-assisted in situ keratomileusis).

A natural condition that results once we age (>40 years old) is presbyopia. It is caused due to the lack of flexibility of the lens and has generally similar effects and treatment as hyperopia.

There are many other conditions, such as retinopathy - caused by diabetes or hypertension; glaucoma etc.

V. PRELIMINARY EXPERIMENTS In order to decide which the best material to

replace the eye muscles is, we have tested several materials, such as elastomer materials, carbon fibers and copper fibers, for thermal and mechanic endurance.

A. Elastomers • have shown a good contractility; • have almost recovered at their initial stage (it is slightly

longer in the end – approx. 0.1 cm).

TABLE I. Deformation of the elastomer (Fig.10).

Length(cm) Force(cN)

10,5 0

11,0 50

11,5 100

12,0 150

11,5 100

11,0 50

10,6 0

Fig.9. Elastomer deformation.

In Fig.9 it can be seen that while increasing the force, the length of the elastomer expands as well. A similar process is seen when diminishing the force. Therefore we can state that the force is directly proportional with the length of the elastomer.

Fig. 10. Elastomer experiment.

B. Copper Fibers • the diameter of the copper fibers is 0.2 mm; • it has responded to electrical tests by heating up

to 50ºC and dilating up to 2 mm at a voltage of 0.60 V and strength of 5 A;

• as seen in the table, the initial force is of 150cN.

TABLE II. Deformation of copper fibers.

C. Carbon Fibers • there were 45 carbon fibers in total, having a

diameter of 0.15 cm all together, sharing a resistivity of 1,2-1,4 .

• when applying current at 1 V and 0.2 A the force decreased with 10 cN and then remained unchanged.

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Fig. 11. Cluster of carbon fibers.

D. Elastic Fibers (with nickeline) • the elastic fibers prove to be

flexible(experiments in Fig.12,13,14) and show a superior plasticity;

• the nickeline fibers, when driven on with a low intensity current, respond by quickly heating up, therefore heating the elastic fibers as well.

Fig. 12. Elastic fibers experiment.

TABLE III. Deformation of elastic fibers.

The deformation of the elastic fibers(Fib.15) is not represented by a linear function and the difference between the initial stage of the elastic and the final stage of the elastic is significant, although they present an equal force.

Fig. 13. Measuring the new length of the elastic fibers.

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Fig. 14. Temperature check for elastic fibers with nickeline.

Fig.15. Elastic fibers deformation.

TABLE IV. The dependency of elastic and nickeline fibers regarding the electric current. Force(cN) Voltage(V) Intensity(A) Power(W) Temperature(°C) Time(s)

50 0.5 0.3 0.15 22 0

48 0.5 0.29 0.15 24 120

48 1 0.57 0.58 ≈24 0

45 1 0.58 0.59 28.2 60

100 1.5 0.8 1.32 25 0

90 1.5 0.8 1.33 33 60

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VI. EXPERIMENTAL MODEL

STRUCTURES Before starting working on experiments, we

tried to predict the suitability of a variety of

materials that can be used as muscles. We have written the result in the following table.

Interpretation: *** most likely ** likely * least likely

TABLE V. Possible materials.

Linear Muscles Circular Muscles Vestibular System

Electromagnetic actuator

** *

Piezoelectric actuator

**

Magneto strictive Actuator

**

Electro thermal actuator

**

Electro strictive actuator

*** *

Piezoelectric micro motor

** **

Magneto strictive Micro motor

**

Electromagnetic micro motor

***

VII. ACKNOWLEDGMENT

We thank ICPE-CA for the support given (materials and guidance for the experiments).

We also thank our understanding head teacher Mrs. Claudia Preda.

VIII. REFERENCES [1] Dan Cristescu, Carmen Salavastru, Bogdan Voiculescu, Cezar Niculescu, Radu Carmaciu, Anatomy Student Book, Corint Publishing House, Bucharest, 2014. [2] http://www.tedmontgomery.com/the_eye/. [4] Guy Croton, Neil Adams, “The Human Body- A Family Reference Guide”, Parraton Publishing House, 2012. [5] Holle Kirchner, Simon J. Thorpe, “Ultra-rapid object detection with saccadic eye movements: Visual processing speed revisited”, Vision Research, vol. 46, issue 11, 2006, pp. 1762-1776. [6] Dale Purves, George J. Augustine, David Fitzpatrick, Lawrence C. Katz, Anthony-Samuel LaMantia, James O. McNamara, S. Mark Williams, “Neuroscience-second edition” , Sinauer Associates, 2001.

IX. BIOGRAPHIES Andra-Maria Ciutac was born on September 13, 1999.

She is a student at the national bilingual high school ‘George Cosbuc’, in the 11th grade. She became a member of the ‘Alexandru Proca’ Research Center in September 2015. Andra obtained a multitude of prizes in biology and chemistry contests in the 8th and 9th grade, which outlined her passion for science. Additionally, she has been a volunteer in hospital for a year and she wants to become a surgeon in the future.

Carmen Gabriela Popa was born on August 22, 1998. She is a student in the 11th grade at the national bilingual high school “George Cosbuc”, being a member of the ‘Alexandru Proca’ Research Center since September 2015. She has been a member of the ‘Shakespeare’ drama club for 7 years and has obtained prizes in national English contests. Carmen is interested in programming and wants to study computer science at the university.

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Abstract - This document is itself an example of the desired layout (inclusive of this abstract) and can be used as a template. The document contains information regarding desktop publishing format, type sizes, and typefaces. Style rules are provided explaining how to handle equations, units, figures, tables, abbreviations, and acronyms. Sections are also devoted to the preparation of acknowledgments, references, and authors' biographies. The abstract is limited to 150 words and cannot contain equations, figures, tables, or references. It should concisely state what was done, how it was done, principal results, and their significance. Index Terms - The author shall provide up to 10 keywords (in alphabetical order) to help identify the major topics of the paper and to be enough referenced.

I. INTRODUCTION This document provides an example of the

desired layout for a published MNE technical paper and can be used as a Microsoft Word template. It contains information regarding desktop publishing format, type sizes, and typefaces. Style rules are provided explaining how to handle equations, units, figures, tables, abbreviations, and acronyms. Sections are also devoted to the preparation of acknowledgments, references, and authors’ biographies.

II. TECHNICALWORK PREPARATION Please use automatic language check for your

spelling. Additionally, be sure your sentences are complete and that there is continuity within your paragraphs. Check the numbering of your graphics (figures and tables) and make sure that all appropriate references are included.

A. Template This document may be used as a template for

preparing your technical paper. When you open the file, select "Page Layout" from the "View" menu (View | Page Layout), which allows you to see the footnotes. You may then type over sections of the document, cut and paste into it (Edit | Paste Special | Unformatted Text), and/or use markup styles. The pull-down style menu is at the left of the Formatting Toolbar at the top of

your Word window (for example, the style at this point in the document is "Text"). Highlight a section that you want to designate with a certain style, and then select the appropriate name on the style menu.

B. Format If you choose not to use this document as a

template, prepare your technical work in single-spaced, double-column format, on paper A4 (21x29.7 centimeters). Set top, bottom margins and right margins to 15 millimeters and left margins to about 20 millimeters. Do not violate margins (i.e., text, tables, figures, and equations may not extend into the margins).

C. Typefaces and Sizes Please use a Times New Roman font. (See

your software’s “Help” section if you do not know how to embed fonts.) Table I is a sample of the appropriate type sizes and styles to use.

TABLE I. Table name will be written in Times New Roman font.

Micromotor Code

b [mm]

a [mm]

h [mm] Material

MPR33 33 25 20 PZT 5 MPR27 27 18 9 PZT 5 MPR15 16 10 10 PZT 5

D. Section Headings A primary section heading is enumerated by a

Roman numeral followed by a period and is centred above the text.

A primary heading should be in capital letters and bolded. The standard text format is considered times new roman 12.

The paper title should be in times new roman 20 uppercase and lowercase letters, not all uppercase.

Author name is set to times new roman 12, institution and contact address (E-mail) are set to times new roman 10.

Financial support should be acknowledged below the author name and institution. Example:

Preparation of a Formatted Technical Paper for the Bulletin of Micro and Nanoelectrotechnologies

*Clara Hender, **Cristian Morari National Institute for Research and Development in Electrical Engineering (INCDIE ICPE-CA), Splaiul Unirii,

No. 313, District 3, 030138, Bucharest, Romania, *clara.hender@icpe-ca.ro, **cristian.morari@icpe-ca

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This work was supported in part by the U.K. Department of Defence under Grant TX123.

A secondary section heading is enumerated by a capital letter followed by a period and is flush left above the section. The first letter of each important starting word is capitalized and the heading italicized.

Tertiary and quaternary sections are accepted only in special cases, so usually must be avoided in order to keep a clear article structure. If required, a tertiary and quaternary section heading must be italicized and enumerated by adding an Arabic numeral after each letter.

E. Figures and Tables Figure axis labels are often a source of

confusion. Try to use words rather than symbols. As an example, write the quantity "Torque," or "Torque, M," not just "M." Put units in parentheses. Do not label axes only with units. As in Fig. 1, write "Torque (cNm)" not just "(cNm)". Do not label axes with a ratio of quantities and units. For example, write "Current (A)," not "Current/A." Figure labels should be legible, approximately 10-point type.

Large figures and tables may span both columns, but may not extend into the page margins. Figure captions should be below the figures; table captions should be above the tables. Do not put captions in "text boxes" linked to the figures. Do not put borders around your figures.

All figures and tables must be in place in the text centered and written with times new roman 10. Use the abbreviation "Fig. 1" in sentence and for each figure name. Each table must be defined as „TABLE I”, with capital letters and roman numbers.

Digitize your tables and figures. To insert images in Word, use: Insert | Picture | From File.

Fig. 1. Total torque function of angular speed. (Note that "Fig." is abbreviated and there is a space after the figure

number.)

F. Numbering Please number reference citations

consecutively in square brackets [1]. The sentence punctuation follows the brackets [2]. Multiple references [2], [3] are each numbered with separate brackets [1]-[3]. Refer simply to the reference number, as in [3]. Do not use "Ref. [3]" or "reference [3]" except at the beginning of a sentence: "Reference [3] shows….".

Number footnotes separately with superscripts (Insert | Footnote). Place the actual footnote at the bottom of the column in which it is cited. Do not put footnotes in the reference list. Use letters for table footnotes.

Check that all figures and tables are numbered correctly. Use Arabic numerals for figures and Roman numerals for tables.

Appendix figures and tables should be numbered consecutively with the figures and tables appearing in the rest of the paper. They should not have their own numbering system.

G. Units Metric units are preferred in light of their

global readership and the inherent convenience of these units in many fields. In particular, the use of the International System of Units (“Système International d'Unités” or SI Units) is advocated. This system includes a subsystem of units based on the meter, kilogram, second, and ampere (MKSA). British units may be used as secondary units (in parentheses). An exception is when British units are used as identifiers in trade, such as 3.5-inch disk drive.

H. Abbreviations and Acronyms

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Define less common abbreviations and acronyms the first time they are used in the text, even after they have been defined in the abstract. Standard abbreviations such as SI, CGS, AC, DC, and rms do not have to be defined. Do not use abbreviations in the title unless they are unavoidable.

I. Math and Equations Use either the Microsoft Equation Editor or

the MathType commercial add-on for MS Word for all math objects in your paper (Insert | Object | Create New | Microsoft Equation or MathType Equation). "Float over text" should not be selected.

To make your equations more compact, you may use the solidus ( / ), the exp function, or appropriate exponents. Italicize symbols for quantities and variables. Use a long dash for a minus sign or after the definition of constants and variables. Use parentheses to avoid ambiguities in denominators.

The number of each equation must be consecutively added in parentheses and arranged at the right margin, as in (1). Be sure that the symbols in your equation have been defined before the equation appears or immediately following.

Don’t use "Eq. (1)" abbreviation instead of "equation (1)", in a sentence.

2AmLm = (1)

with m - mechanical mass, A - force factor, mL - electromechanical inductance.

III. ACKNOWLEDGMENT The following is an example of an acknowledgment. The authors gratefully acknowledge the contributions of

Mircea Ignat and Puflea Ioan for their work on the original version of this document.

IV. APPENDIX Appendixes, if needed, appear after the

acknowledgment.

V. REFERENCES References are important to the reader;

therefore, each citation must be complete and correct. There is no editorial check on references, only the format Times new roman 10 must be considered.

[1] Satanobu J., Lee D.K, Nakamura K., Ueha S., ”Improvement of the Longitudinal Vibration System for the Hybrid Transducer Ultrasonic Motor”, IEEE Trans. On Ultrasonic ferroelectrics and Frequency Control, vol. 47, no. 1, January 2000, pp. 216-220. [2] Morita T., Yoshida R., Okamoto Y., Kurosawa M., ”A Smooth Impact Rotation Motor Using a Multi-Layered Torsional Piezoelectric Actuator”, IEEE Trans. On Ultrasonic ferroelectrics and Frequency Control, vol. 46, no. 6, November 1999, pp. 1439-1446.

VI. BIOGRAPHIES A technical biography for each author must be

included. It should begin with the author’s name (as it appears in the byline). Please do try to finish the two last columns on the last page at the same height. The following is an example of the text of a technical biography:

Mircea Ignat was born in Bucharest on March 4, 1953.

He graduated at 1977 and he received Ph.D. degrees in electrical engineering from Bucharest Polytechnic University in 1999.

His employment experience included the National Institute for Research and Development in Electrical Engineering ICPE-CA, Dep. of Electrical Micromachines Research and he is the head of Electromechanics Department.

The research preoccupation include: the synchronous generators and the high speed electric machines. He is member of IEEE.

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