© Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Industrial Engineering and Ergonomics
Dr.-Ing. Dr. rer. medic. Dipl.-Inform. Alexander Mertens
Univ.-Prof. Dr.-Ing. Dipl.-Wirt.-Ing. Christopher M. Schlick
Chair and Institute of Industrial Engineering and Ergonomics
RWTH Aachen University
Bergdriesch 27
52062 Aachen
phone: 0241 80 99 494
email: [email protected]
Unit 9
Ergonomic Design I:
Anthropometry and Digital Human Models
Fall Winter 2016/2017
10 - 2 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
To understand the need for ergonomic design
To get to know design criteria and requirements
To learn anthropometric foundations
To understand possibilities of movement, vision and reachability
analyses
To learn about computer-aided methods and modelling tools
Learning Targets
10 - 3 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
http://www.baddesigns.com
Introduction - Ergonomic Product Design?
10 - 4 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Aspects • Anthropometry (reachability, visibility)
• Energetic-effect. design (forces, effectiveness)
• Informational design (displays, visualisation)
• Software and graphical user interface design
(user guidance, structure)
• Colour coding and form design (Industrial design)
Greek: work or activity “ergon”
Greek: control, order, law “nomos”
focuses on human beings and their interaction with
products, equipment, facilities, procedures, and
environments used in work and everyday living
Ergonomics
Usability
Engineering
focuses on the process of ergonomic product
development
“producere” Greek: produce, create
What is Product Ergonomics?
10 - 5 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Ergonomic Design – Example 1
Anthropometry
• Field of View
(exterior view, displays,
occlusions)
• Reachability
• Actuating forces
(Pedal force, switch
forces, steering force)
• Comfort
Displaying Information
• Display Concept for the
multifunctional display
• Manual Control (Side-Stick-Control,
„Drive-by-Wire“)
Semi-autonomous
driving and assistance
system
(concept study F 015 Imagination from Daimler, 2015)
10 - 6 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Anthropometry
•Field of View (Programmable multi-vision
display and infrared night-view
system)
• Reachability
• Actuating forces (Pressure-sensitive electronic
controls)
•Comfort
Displaying Information
•Display Concept
• Operating devices
(Side-stick-steering,
“Fly-by-Wire”)
(Cockpit of an Airbus A380)
Ergonomic Design – Example 2
V10-1 Cockpit A380
10 - 7 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Prospective and Corrective Ergonomics
Prospective Ergonomics
product development
under consideration of
ergonomic aspects
Existing
Product
Necessary
Improvements
Unsatisfactory
Working Conditions
Adjustments on
the Product
Corrective Ergonomics
correction of ergonomic
shortcomings in existing
products;
(adapted from Pahl & Belltz., 1997)
Solution
Conceptual Design
Embodiment Design
Detailed Design
Product Planning &
Clarification of the task Ergonomic
evaluation
Definition of target group & product concept
Issue the development request
Ergonomic
evaluation
Ergonomic
evaluation
10 - 8 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Modification Costs in different Phases
of Product Development
Idea Final
Design
Testing Process
Planning
Production Use
Bulk
Production
Batch
Production
Individual
Manufacturing
Modification
costs
Conceptual
Design
Embodiment
Design
(Ehrlenspiel, 1995)
Quality
gates
10 - 9 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Ergonomic Design Criteria
Harmlessness
Feasibility
Avoidance of interferences
Personality development
Consideration of maximum forces, Avoidance of harmful body positions and overstraining
Reachability of operating elements, Visibility of instruments
Comfort considerations, optimisation of the information flow
Design questions, individualisation of the geometrical as well as the biomechanical interpreted information flow
General ergonomic
design criteria
Anthropometric
design criteria
1
2
3
4
+
+
-
-
-
-
+
+
Reali-
sation
* The right for personality development is written down in the constitution
*
10 - 10 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Ergonomic Requirements
Functional Requirements
e.g. - effective and ease of use
- avoidance of human error
- fast and easy learnability of use and application
- good perception of information or objects
- accurate and safe adjustment by control devices
Strain –related Requirements
e.g. - bearable strain
- no annoyance (like noise) for the user
- Accommodativeness for the user
- no risk for injuries
Requirements derived from Side Conditions
e.g. - consideration of importance, frequency of use, and sequence of use
- hygienic and skin friendly materials
- aesthetics / emotional effects.
10 - 11 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Anthropometry
Mediaeval buildings based on human proportions
Anthropometry in medicine
da Vinci's
Divina proportione, 1509
Anthropometry in art
and first approaches in product
design
Anthropometry
Science of measures, porportions and measurements of the human
body (body measurements, movements, masses, forces).
„Gerechte Feldrute“ (engl. „Fair birch“)
(Copper engraving)
10 - 12 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Anthropometric Measures
Body sizes
Body height and length
Sizes of limbs / reachability
Volume
Corpulence
Angles of movement
Forces
Extensive Standards (DIN 33402 ff)
Inquiries (posture, clothes, measurement points, measurement tool)
Description of sample (gender, age, region)
Areas of application
Index values
Estimation of physique and corpulence
VITUS 3D-Laser Scanner
10 - 13 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Distributions of Body Heights c
um
ula
tive
ab
so
lute
fre
qu
en
cy [
%]
body height [mm] (DIN 33402)
population 16 to 60 years of age men
90
80
70
60
50
40
30
20
10
0
3 4 1 2
2000 1900 1800 1700 1600 1500 1841 1725 1629 1510
men women
women
Body height classes
5th percentile women
5th percentile men
95th percentile women
95th percentile men
3
4
1
2
10 - 14 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Body Dimensions of a unclothed, standing human
5. 50. 95.
f 1510 1619 1725
m 1629 1733 1841
f 1402 1502 1596
m 1509 1613 1721
f 1234 1339 1436
m 1349 1445 1542
f 957 1030 1100
m 1021 1096 1179
f 664 738 803
m 728 767 828
f 616 690 762
m 662 722 787
f 323 355 388
m 367 398 428
percentile
1.4 stature/ body height door ways
name examples
1.5 eye height arrangement of scales, visual tasks
1.6 shoulder height standing room, ramps
1.7 elbow height desks, sales counter and bars
1.9 functional down- ward reach with both arms
trunks, bags, roller-cases
1.1 functional for- ward reach
controls, key panel
1.10
shoulder breadth (biacromial widths)
width of prison bars
(DIN 33402, Part 2)
average of 16 to 60 years of age
Human body dimension tables are also available for sitting
persons and for dimensions of fingers, hands, feet, and heads.
10 - 15 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Differentiation of the user groups
Gender differentiation Percentile 5. 50. 95.
Men 1629 1733 1841
Women 1510 1619 1725
Values DIN 33402 (Tallness [mm]: Part 1 – Value definition , Part 2 - Values )
Age differentiation 18-19 m 1681 1789 1906
20-25 m 1683 1788 1912
26-40 m 1665 1764 1870
Values Handbook of ergonomics (Body height [mm])
Region / Land USA 1640 1755 1870
S 1630 1740 1850
F 1600 1715 1830
D 1629 1733 1841
JP 1560 1655 1750
IND 1535 1640 1745
Clothing – ca. 3-4 cm for shoes, etc. All height measures undressed, in [mm]
10 - 16 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Acceleration – Is the limit reached?
Increase of body heights of military recruits in Germany and
Switzerland currently stagnates.
Staub et al. (2013)
Mean body height of military recruits in Switzerland and Germany 1952-2011
Year of recruitment
Germany (from 1992 incl. former DDR) Switzerland
10 - 17 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Distribution of Body Sizes:
Height and Corpulence
Body sizes are not independent but correlate with each other in diverse ways
Statistic factor analysis documents three variation arrays
Body height (small – big)
Corpulence (slim – corpulent)
Proportion (long – short legged)
So the product design must consider different dimensions besides height
2 x 2 x 2 = 8 values for the whole population
Corpulence
Body h
eig
ht
Coordinates of body sizes in the system of body height and corpulence
Body height
Proportion
Corpulence
very tall, slim and
long-legged
tall
slim
long-
legged
corpulent
short-legged
short
very short,
corpulent and
short-legged
10 - 18 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Physical strength of human beings
Muscle
moment
Muscle
power
Inertia force
(forearm)
Applied force
(affects the grip)
Physical Strength is the power developed by the human body.
It can be separated in muscle,- inertia,- and applied forces:
Muscle force: operates through muscle activity inside a body
Inertia force: reacts of the mass of a body through force of inertia
Applied force: Physical strength operates external to the body
Ex. finger, hand, and leg forces
Physical strength is determined by the following figures:
magnitude of force F in Newton [N],
location of the force application point relative to the body,
direction of the line of action of the force relative to the body,
direction of force (with and against gravity).
10 - 19 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Information release – motivity–
Example for the determination of static applied forces
Isodynes describe “lines of equal maximum exerted force” depending on the position of the body and the effective length of the arm. Different diagrams for points of application of force or moments as well as several diagrams of sidewise deflections are provided.
P3
a
P3 P1,P2
Applied force (affects the grip)
P1,P2
Inertia force (forearm)
Muscle
power
Source: DIN 33411-4 1982
P1: Proximal wrist
P2: Distal wrist
P3: Shoulder joint
α: elevation angle between
conduit P1-P3 and the
horizontal plane
β: deflection angle between
conduit P1-P3 and the
plane of symmetry of the
body
a: Distance P1-P3
amax: Maximal distanceP1-P3
(streched arm)
a/amax: Relative arm range
Forces in N
10 - 20 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Maximum Isometric Action Forces
Action Force
[N]
Fre
qu
en
cy women
50th
(452) 5th percentile
(271)
95th
(605)
men
50th
(829) 95th
(1051) 5th percentile
(560)
Body Height
[mm]
Fre
qu
en
cy men
50th (1733)
95th
(1841) 5th percentile
(1629)
women
5th percentile (1510)
95th
(1725) 50th
(1619)
(DIN 33411-5)
(DIN 33402-2)
10 - 21 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Functional Measures:
Active area of the hand-arm-system
The grasping distance is every area in which objects can be touched, grasped or
moved by hand.
Influencing Factors
• Body posture/position
• Range of movement of joints
• Direction of movement and forces
• Necessity of equilibrium
• reduced possibility for movement
with greater muscular strain
• Age
Manual Assembly Workplace (Sanders & McCormick, 1993)
10 - 22 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Functional Measures: Movements
Postures are never static, but always include dynamic
portions
Work is always connected with movements
Movements must be considered in product ergonomics
Problem:
Inter-individual variance of movements increases the variability of body sizes
Degrees of freedom of movements lead to an extreme number of variant movements (e.g. Hand-Arm-System >100 dof)
10 - 23 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Phases of a Movement
???
Stim
ulu
s
Stim
ulu
s
G E S A M T B E W E G U N G WHOLE MOVEMENT
Planung Planning Ausführung Execution Zie
l G
oal
Recognition,
Comprehend
Cognition
of the goal
Perception
Movement
planning
Intention,
programming of
movements
Cognition
Ballistic sequence
of movements
Fast but inaccurate approach
to the goal without regulation
Motor activity
Visually
controlled
phase
Fine tuning,
Reaching of the
goal
Perception,
Cognition,
Motor activity
Time
Ve
locity
Ballistic phase
Visually controlled
phase
10 - 24 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Characteristics of a Movement
Temporal characteristic data
(Access time)
Spatial characteristic data
(maximum lateral deflection)
Course of movement
(Differentiated Analysis)
Biokinematic Models
(Simulation)
Movement from a defined starting point to a certain target point in the vertical plane.
Schmidtke: Handbook of Ergonomics
Index finger-motion according to Alexander (2002)
0 10 20 30 40 50 60
BILD
-300
-200
-100
0
100
X
x(t
)
0 10 20 30 40 50 60
BILD
200
300
400
500
600
700
800
900Y y
(t)
0 10 20 30 40 50 60
BILD
0
100
200
300
400
500
600
700
800
Zz(
t)
Motion width of
the index
finger tip
Average time (s) for an edge length of the target face of
years years years years years years years years years
10 - 25 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Sight Analysis: Field of View
Visual field Field-of-view (fov) Extended fov
Fixation With recumbent
head and eyes
With recumbent
head and moving
eyes
With moving head
and eyes
Horizontal,
Flash lights
Monocular: -60 to +90°; Binocular: -60 to +60° (opt. 15°)
Monocular: –75 to +110°; Binocular: –75 to +75° (opt. 30°)
Monocular: –125 to +160°; Binocular: –125 to +125° (opt. 55°)
Horizontal,
Colour
lights
-19 to +32° green, -20 to +36° red, -27 to 47° blue/yellow
-34 to +47° green, -35 to +51° red, -42 to +62° blue/yellow
-84 to 97° green, -85 to +101° red, -92 to +112°blue/yellow
Vertical,
Flash lights
-75 to +50° -85 to +65°
-90 to +110°
Field of view airplane
Analysis of the field of view
10 - 26 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Somatography and Body Contour Templates
Bosch Template "Kiel Doll"
Template-Somatography
Body contour template,
here a side view to evaluate
the sitting position of a truck
driver
(DIN 33408, Teil 1; Pahl & Beitz, 1997)
10 - 27 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Digital
mannequin
•Anthropometry
•Field of view
•Maximum
forces
•Simulation of
movements
•Tools for analysis
CAD-Model of the product
Procedure for Computer-aided Methods
Rapid-Prototyping
Analysis in CAD (early design phase)
Field of view
Reachability
Comfort
10 - 28 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Generation of the First Mannequin
Direct input of body sizes
Database inquiry
(male) (female) (Child)
(very short) (short) (medium) (tall) (very tall)
(height)
(sex)
(corpulence)
(slim) (medium) (corpulent)
(proportion)
(sitting dwarf) (average) (sitting giant)
(hand model)
(gripper hand) (5 finger hand) (nude)
(Cancel)
(nationality)
(year of
reference)
(age group)
(German)
Mannequin RAMSIS in CAD
10 - 29 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
1.Definition of reference
points and planes
2. Definition of body parts 3. Animation
Definition of Boundary Conditions for Positioning
(targets) (boundary) (fixation) (joint) (grip types) (pelvis) (direction) (torsion attitude)
10 - 30 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Analysis of field of vision and spaces within reach
Field of vision (Cone) and outside view Spaces within reach and reachability
10 - 31 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Analysis of Posture Comfort (I)
Body Measures
(general) Joint Angles
(product specific)
Mass, Center of Mass
(detailed)
(Overall body mass)
(Overall center of mass)
10 - 32 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Analysis of Posture Comfort (II)
(Overall Rating)
(Exhaustion)
(Incommodiousness)
(Bodypart Discomfort)
(Neck)
(Shoulders)
(Back)
(Fundament)
(Left Leg)
(Right Leg)
(Left Arm)
(Right Arm)
(Health Evalution)
(Backbone)
(Reference)
(Set reference) (absolute) (Close)
10 - 33 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Iteration of the Analysis with Different Models
Problem !
10 - 34 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
ATTENTION ... Mannequins make mistakes, too
Mannequins are important tools and appliances on the one hand, on the other
hand they do not replace the expertise of the engineer.
An individual survey and classification of the results is necessary to
identify and avoid defective analysis results.
Example: Calculated analysis result of a mannequin. Similar results can also be found with different
products. (Conradi, 2002)
10 - 35 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Computer-aided Methods - RAMSIS
(www.human-solutions.com)
RAMSIS - 3D-CAD-Tool for the ergonomic design of cockpits
and interiors.
• Generation of animations
• Task-oriented simulation of postures
• Task-oriented simulation of movements
• Analysis of body types
• Analysis of health and comfort
• Simulation of the field of view and field of
view in the mirror
• Force analysis
• Analysis of the safety belt
• Analysis of reachability
10 - 36 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
JACK
Mannequin for product design
and in areas of education.
Main scope
- Virtual environments (VU),
- Computer graphics,
- Product development
Database (mainly US)
Analysis
- Vision, reachability, posture,
movements
http://www.plm.automation.siemens.com/en_us/products/tecnomatix/assembly_planning/jack/index.shtml
Computer aided Methods – Siemens PLM JACK
10 - 37 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Computer-aided Methods – DELMIA Human
Main scope
- Product development/vehicles
Complex database
Statistic modelling
Analysis
- Vision, reachability, posture,
movements
- MTM, Analysis of forces and
efficiency
http://www.safework.com/delmia/delmia_sw.html
DELMIA Human
Mannequins and complex
CAD simulation environment.
10 - 38 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
What is the relationship between prospective and corrective ergonomics?
What are the different levels of ergonomic design criteria?
What are the different anthropometric measures and what are they used for?
Which influencing factors must be taken note of, and what does the the distribution of measures look like?
What is a percentile?
What are the different phases of the movement sequence?
Which fields of vision must be differentiated?
What are the areas of application for virtual human models/mannequins and what advantages do they present in the product development process?
Questions to exmine your success in learning
10 - 39 © Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University
Baber, C.: Human Factors Methods: A Practical Guide for Engineering and Design; Ashgate Publishing;
22. Dezember 2005; ISBN 978-0754646617
Brookhuis, K.; Stanton, N.; Hedge, A.: Handbook of Human Factors and Ergonomics Methods;
Routledge Chapman & Hall; 16. Januar 2008; ISBN 978-0415287005
Landau, K.; Luczak, H.: Ergonomie und Organisation in der Montage; Fachbuchverlag Leipzig, 2001,
ISBN 978-3446215078
Laurig, W.: Grundzüge der Ergonomie. Erkenntnisse und Prinzipien. Beuth; 4. Auflage; November
1992; ISBN 978-3410365808
Salvendy, G.: Handbook of Human Factors and Ergonomics; Wiley & Sons; 3. März 2006; ISBN 978-
0471449171
Sanders, M.; McCormick, E.: Human Factors in Engineering and Design; McGraw-Hill
Science/Engineering/Math; 7. Auflage; Januar 1993; ISBN 978-0070549012
Schmidt, L.; Schlick, C.; Grosche, J.: Ergonomie und Mensch-Maschine-Systeme; Springer Berlin; 1.
Auflage, 25. April 2008; ISBN 978-3540783305
Staub, K., Woitek, U., & Rühli, F. J. (2013). Grenzüberschreitende Zusammenarbeit mit
anthropometrischen und medizinischen Daten der Rekrutierung. Swiss Rev Mil Disaster Med, 1,
41-45.
Tilley, A. R.: The Measure of Man and Woman: Human Factors in Design; Wiley & Sons; 13. Februar
2002; ISBN 978-0471099550
Wickens, C. D.: Introduction to Human Factors Engineering: International Edition; Pearson Education
(US), 2. Auflage; 11. Dezember 2003; ISBN 978-0131229174
Literature