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Procedia Engineering 63 (2013) 547 – 555 Available online at www.sciencedirect.com 1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of Universidad de Zaragoza, Dpto Ing Diseño y Fabricacion doi:10.1016/j.proeng.2013.08.260 ScienceDirect The Manufacturing Engineering Society International Conference, MESIC 2013 Precision study of a coordinate measuring machine using several contact probes I. Puertas a, *, C.J. Luis Pérez a , D. Salcedo a , J. León a , R. Luri a , J.P. Fuertes a a Mechanical, Energetics and Materials Engineering Department, Public University of Navarre, Campus de Arrosadía s/n, 31006, Pamplona, Navarra (Spain) Abstract In this research work, a comparative study between the precision obtained with a touch probe (TP-200) and that obtained with a scanning probe (SP-25) is carried out for a specific coordinate measuring machine (CMM). These two types of probes cover the most commonly used contact probes in CMMs, where touch probes work by making contacts with the part and scanning probes maintain the contact with the part as they scan along its surface. In order to do this, one part was manufactured by machining and a series of measurements were taken over it at distinct locations in the CMM working volume. This part consists of parallel planes with different height values (70 mm, 45 mm, 25 mm and 10 mm) from the horizontal plane located on the granite table. The above-mentioned part was measured at five different locations distributed along the working volume and the measurements were repeated three times, where all of them were taken at a temperature of 20 ºC ± 1 ºC. Moreover, not only the CMM uncertainty is taken into account but also the variability associated with the manufactured part along with the measuring process of it. Keywords: CMM; Uncertainty; Precision 1. Introduction Dimensional precision of manufactured parts is a matter of the greatest importance, especially in cases where these are to be in contact with each other. Measuring with precision is imposed by the need for manufacturing * Corresponding author. Tel.: +34-948-169305; fax: +34-948-169099. E-mail address: [email protected] © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of Universidad de Zaragoza, Dpto Ing Diseño y Fabricacion

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cremation, unless it be taken to be shown by paesive refusaland contrary preference. The example of early timesunder which the owners of the most venerated names werelaid in the earth from which they arose has guided this pre-ference, the existence of which is evident. The sentimentis a worthy one. Nothing can be gained by seeking tocrush it, nor is there anywhere a desire to do this. Itneed not imply opposition to the proved necessitiesof sanitary existence, not even to cremation if in any casecapable of such proof, and its free exercise under wholesomeconditions remains as much a common right as the libertyto burn where the cause of death can be clearly shown.

HONOURS TO PROFESSOR KOCH.

THE German Emperor has conferred on Professor Kochthe Grand, Cross of the Red Eagle, in recognition of

the value of his important discovery. The insignia werehanded to the Professor by the Emperor personally. Thisis the first time since its bestowal on von Humboldt that aGerman scientist has received the above honour. Professor IKoch has also been presented with the freedom of the cityof Berlin-an honour shared byonlytbree otherdistinguishedmen-namely, Prince Bismarck, Count von Moltke, and Dr.Schliemann.

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A NEW USE FOR HOSPITALS.

THE adoption in Germany of the law of compulsory, Iinsurance for workmen whose wages reach a certain

standard, and the stimulus thus given to insurance IIgenerally, have led to quite a novel use being madeof a considerable number of beds in many of the

large hospitals. In the report of the Berlin Charite

Hospital for 1888-89, recently issued by the director,Dr. Mehlhausen, this subject is specially referred to. Aconsiderable addition has been made to the labours of boththe medical and clerical staff, owing to the above circum-stance. Many persons who have suffered injuries, theduration and full extent of which were not quite apparentto the private practitioner who has them under care, alsopersons who did not feel satisfied with the pecuniarydamages awarded to them for accidents, have entered thehospital more with a view to their progress being keptunder observation than for actual treatment. The autho-rities have offered every facility for the admission of suchcases, in so far as they have not interfered with moreserious ones. They regarded it as very desirable to do sobecause such doubtful cases, which usually consist ofnerve disease, involving great difficulties of diagnosis, andwhich are frequently regarded by the person responsible forthe injury and damages as simulated, present features ofthe greatest value from an educational point of view. Theaddition of this new work to the hospital has involved theclerical staff in an enormous correspondence, and has thrownupon the medical staff, in addition to their professional work,a most responsible and difficult task in the preparation ofreports on the cases. -

DIPHTHERIA IN ANIMALS.

IN an editorial article in the Veterinary Journal for

November, Professor Walley calls attention to the paucityof evidence in support of the opinion that diphtheria inman is often to be attributed to transmission from thelower animals. He rightly asserts that the question is onewhich should be settled in the interest of hygiene. As

regards horses, experience enables him to assert positivelythat they are exempt from the disease. He traversesthe statement lately made that outbreaks among peopleliving near horses and the alleged greater proportion of

diphtheria among cavalry than infantry, is to be assignedto infection from the horse. The only instance of cattleaffected with a disease resembling diphtheria is one

recorded by himself some years ago, where some calve9and their attendants were affected, but he now thinksthere were grave doubts as to whether the affectionwas diphtheria. Dogs appear to be exempt, but cats havesuffered from diphtheria, probably infected from humancases. Fowls and pigeons suffer from a disease somewhatresembling diphtheria, but more positive evidence isneeded to warrant a conclusion that this is communicable to,the human species. "In fact," he says, "there is not aninstance, as far as is at present known, of animals trans-mitting this specific, and, it might be said, peculiarlyhuman disease to mankind," and without venturing to.

assert that such may not occur, he thinks it is most un-

likely. He invites records of observations of diphtheria inanimals in order to assist in elucidating the mystery thathangs over the etiology of the disease.

"À BERLIN !"

IT may prove useful to medical men about to join theextraordinary number of their colleagues already in Berlinto invite them to calmly reconsider their plans. What do

they hope to gain by going there? What they will gainwill be this : If they are energetic and can endure equeezingand crushing, they may join the crowds of doctors fromevery known land who surround the beds occupied bypatients under treatment by Koch’s method. One of thestaff will address briefly those immediately surrounding thebed, while the scores or hundreds who are crushing aroundthis inner circle remain absolutely ignorant of what is.

being said or done. The cicerone passes from patient to.patient in a few minutes, and then the demonstration is,over. Should the energetic visitor manage to be wen

placed at the bedside, can he gain much by the brief in-spection of the patient lasting a couple of minutes? Cansuch a visit or several such impart any instruction ? If thevisitor cannot speak German, of course the difficulties aregreatly increased ; indeed, they become insuperable. Theactual inoculation is precisely similar to any other sub-cutaneous injection, yet hundreds of medical men may beseen fighting and crushing their way to see this, as if itwere something important. Anyone seriously interested inthis question would act wisely to first learn all that he canas to the method-and we hope to keep our readers weldinformed-and await some practical results, and afterwards,if he thinks it desirable, go to Berlin for some weeks. To

go for a few days, as so many have done, is merely waste oftime and money.

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DYSENTERY CAUSED BY CALOMEL INJECTIONS.

THE hypodermic or intra-muscular injection of calomesuspended in oil, which is a form of treating syphilis muchmore practised abroad than in this country, is not withoutoccasional inconveniences; thus Dr. Cramer reported a shorttime since a case where, after six injections at inteivals ofa week, a patient became the subject of very severe dysen-tery. This accident was not due apparently so much to anyidiosyncrasy of the patient as to the fact that he had beensecretly dosing himself with iodide of potassium, which permitted a large quantity of mercury to collect in his tissues.

FOREIGN UNIVERSITY INTELLIGENCE.Berlin.--Professor Fliigge, Director of the Hygienic

Institute in Breslau, has been appointed Director of theHygienic Department of the New Bacteriological Institute.Cracow.-Dr. Mars has been promoted to an Extra-

ordinary Professorship of Midwifery.Kharkofl.-Dr. Tolochinoff has been promoted to the.

Professorship of Midwifery.ZM’eA.—Dr. Geisler has qualified as privat.docent in

Medicine.