Industrial Engineering and Ergonomics - Startseite - · PDF file© Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University 10 - 2 To understand the need

© Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University

Industrial Engineering and Ergonomics

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 99 440

email: [email protected]

Unit 9

Ergonomic Design I:

Anthropometry and Digital Human Models

Fall Winter 2012/2013

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


http://www.baddesigns.com

Introduction - Ergonomic Product Design?


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?


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“)

(Concept study F 200 Imagination by Daimler, 1996)

Ergonomic Design – Example 1


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

../01_Final/1 Airbus A380 cockpit_ at FIDAE 2008.avi


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


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


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

*


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.


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)


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


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


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.


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]


Acceleration

Increase of body heights of adults in Sweden during 80 years.

Acceleration is the technical term for the general increase of body dimensions.

(Braunfels, 1973)

body h

eig

ht

[cm

]

8,4 cm

(4,9 %)

164

166

168

170

172

174

176

178

1880 1930 1890 1900 1910 1920 1939 1949 1961


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


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).


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


Maximum Isometric Action Forces

Action Force

[N]

Fre

qu

en

cy women

50th

(452) 5th percentile

(271)

95th

(605)

men

50th

(829) 95th


(560)

Body Height

[mm]

Fre

qu

en

cy men

50th (1750)

95th


(1650)

women

5th percentile (1535)

95th

(1720) 50th

(1625)


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)


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)


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


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

../Lehre/Vorlesungsunterlagen/AW I - BO/Analysedaten/WORK/VRML/Konsole_Creator.wrl


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 +95°; 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 +15° -85 to +25°

-90 to +110°

Field of view airplane

Analysis of the field of view


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)


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


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


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)


Analysis of field of vision and spaces within reach

Field of vision (Cone) and outside view Spaces within reach and reachability


Analysis of Posture Comfort (I)

Body Measures

(general) Joint Angles

(product specific)

Mass, Center of Mass

(detailed)

(Overall body mass)

(Overall center of mass)


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)


Iteration of the Analysis with Different Models

Problem !


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)


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


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


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.


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


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

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

Industrial Engineering and Ergonomics - Startseite - · PDF file© Chair and Institute of Industrial Engineering and Ergonomics, RWTH Aachen University 10 - 2 To understand the need

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