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Technical systems must be supervised or operated by humans in all aspects of
human-machine-environment systems, e.g., in the household, automobiles, consumer
electronics, or in traffic. These examples show – and everyone has probably had
experience with these – that the design of systems provided to humans is not always
optimal, i.e., user-friendly. In order to offer hazard-free handling and error-free human-
machine interaction, it is vital that the characteristics and capabilities of future users
are taken into account. In addition, the ergonomic design of products has substantial
meaning for the acceptance of appliances. A mobile phone, for example, that is more
complicated to operate than competitors’ products (because fundamental ergonomic
principles were not incorporated) is no longer capable of competing in today’s market.
Early inclusion of ergonomic aspects during product development thus also leads to a
better market position and a reduction in costs due to later product changes.
Design of products, however, continues to be not seldomly left up to designers and
draftspeople who do not have specific knowledge on ergonomics. This can clearly be
seen in the design of current consumer electronics products, computer software and
mobile telecommunications: the user is completely overwhelmed by the excess of
functionality and highly complex system structures (e.g., nested menus, hidden
functions).
What is Product Ergonomics?
What is Usability Engineering?
Product ergonomics involves adapting products to their users’ characteristics so that
the products can be used more easily.
Anthropometry in product ergonomics primarily involves consideration of measures
and measurement ratios in the design of future product and work places. Based on
body dimensions, cars, for example, have their seating geometry, layout of operating
elements (steering wheel, gear shift, pedals), operating force as well as the visibility of
their instruments laid out.
The principles introduced in the information technology design can usually also be
transferred to the design of software.
The design of a vehicle cockpit (here: an innovative concept study from Daimler)
places high demands on the anthropometric design. This includes visibility, referring
to the exterior view, visibility and readability of displays and instruments, occlusions
(e.g. through the steering wheel or manual controls) as well as the reach
(reachability and operation of actuators) or the actuating power (operation of
pedals, switches and steering elements). Furthermore, considerations regarding the
comfort of sitting postures have to be made, which is especially important for long
distance travel.
An important innovation of the depicted concept study is the driving dynamics
system. Here, the driver controls all car movements with the help of so-called side-
sticks, placed on the interior mantling of the doors and the center console. In order
to steer, the driver moves the side-sticks to the left or to the right, to break he pulls
them backwards and if he wants to accelerate he moves them forwards. Common
control or connecting elements like steering wheel, steering column or pedals do
not exist. The translation of driver commands solely takes place electronically.
Therefore domain experts use the term “drive-by-wire” for this kind of system (of
course, “wire” is not meant literally but refers to the power cables for the
transmission of electronic signals).
Mercedes Engineers placed cameras into the prominent stainless steel covers on
the glass roof in order to replace interior and exterior mirrors. The driver is
comprehensively informed about the traffic situation behind him through screens
The second example is of an airplane cockpit for a study of a passenger plane with
two motors based on the AIRBUS cockpit concept. Through the airplane’s outer
structure the outside view and the position of the pilot is given in the cockpit. Aside
from the numerous SAE, JAR and FAA standards, particularly long operational
durations and the wide spectrum of global users are typical for cockpits.
From a anthropometric perspective, taking visibility into consideration, i.e. outside
view at start and landing and during taxiing on the runway, and visibility of
instruments, is just as important as the reachability of operating instruments through
various safety belt functions with a 5-point belt. With the Fly-by-Wire artificial steering
forces contribute to easier steering. Paying attention to posture comfort is especially
important for long flights (transatlantic).
A similar concept is found in several AIRBUS airplanes and makes the re-training of
pilots from one type to another more simple. This is necessary in almost all airlines
during the course of a career/promotion. Actually, the user interface of an
A319/320/321 can be distinguished from that one of a A330/A340/A380 only by the
design. But regardless the same user interface elements, it is important to say that
flight characteristics and flight dynamics can be significantly different.
In practice, mostly a mixture in design exists:
Purely prospective/planning ergonomics is impossible e.g. in automobile creation
since standards and pre-designs must be taken into consideration as a basis. A
benefit of a pre-design is, through the identification with the brand, an easy transition
from one type to the next: this minimises the training time and increases the reliability.
A continuous modification of existing driver workplaces results, which leads to a
mixture of various ergonomic approaches.
The later changes and counterbalancing measures are recognised and put into
action, the higher are the resulting costs and necessary recalls. A strict adherence to
deadlines with simultaneous high quality is increasingly more difficult, especially in
relation to the increasing relevance of the “just in time” delivery and the
consequences of delays
There is a close relationship between general ergonomic design criteria and
anthropometric design. Therefore, the maximum forces acting on humans are to be
taken into account in terms of harmlessness. Obviously, a failure to notice can easily
lead directly to health damages (e.g. slipped discs during lifting). The feasibility must
be ensured through a meaningful layout of operating elements (reachability,
operation) and instruments (visibility). A product such as an automobile cannot be
steered if important elements like the steering wheel or the pedals are not reachable
for the majority of users. In regard to higher criteria such as tolerability and avoidance
of interference, damaging body postures and overstraining are to be avoided; it is also
important to ensure a high level of comfort through the design. Personality
development answers general questions regarding “well-being”. However, aspects of
colour design for the instruments as well as design aspects are more related to
aesthetic levels.
Three requirements of ergonomic design of products can be derived from slide 10-10.
The historic foundations of anthropometry are, aside from the representation of
humans in art, especially found in architecture. As humans were often seen as an
image of God, “godly” and perfect proportions were thought to be made possible by
incorporating human proportions into building design. Thus, many medieval
structures, particularly sacral buildings, are based on human proportions.
Body measurements were also used in daily life as a form of measurement. The
reason for this is the lack of a universal relative measurement system, such as the
“Urmeter”. Instead, available body measurements would be used: the inch is the
length of the first thumb joint, a cubit the length from the elbow to the tip of the finger,
and paths could be measured with the even “Feldrute” in which 16 people would line
up in a row, one behind the other.
With the Renaissance anthropometry was used in medicine, especially in anatomy, in
order to scientifically identify the skeletal structure and the inner composition of the
human body.
Da Vinci in particular occupied himself with solid results about the build of the human
body. His goal was a representation in beautiful artwork, but also the practical use of
the acquired anthropometric insights in the design of tools. As appliances or tools
were until now only developed through “evolution”, i.e. good designs were pursued,
bad ones were discarded, a goal oriented, almost scientifically engineered design
was now possible.
There are numerous anthropometric measures. These days the principle that counts
is: what can be measured will be measured. In sight of product ergonomics, there is
still a large portion of the total measure that is interesting. These are listed here. An
overview of large data collections can be found in the standards. Besides body sizes,
general conditions for data collection can be found here. These must be adhered to in
implementation since errors may otherwise occur. For example, most body sizes are
collected from unclothed persons in standard positions (perpendicular seating): this
case can rarely be found in practical usage however. Therefore, safety margins are
necessary during product design. Additionally, differentiation/characterisation of
measured samples must be taken into account since there are great differences in
body sizes as well as body proportions between the sexes, age groups and regional
groups. Different body sizes are often combined for general characterisation of
physique and corpulence. Thus, heavy-set short people can openly be distinguished
from lean people, which can then also be taken into consideration during product
design.
The limitation of using only one value for the description of body size (e.g. the
average) is not reasonable since more than one user will be using a product later on.
Instead, percentages are used in anthropometry which cover a range. A percentage
indicates how much of the population fall below the measurement. The 5th percentile
thereby refers to a short person since only 5% of the entire population are shorter.
The 95th percentile is a tall person, since 95% of the population is shorter and only
5% is taller. Length measurements such as body height are normally distributed so
that a simple relation between percentile and mean/standard deviation exists. The
mean relates to the 50th percentile (50% are shorter than that measurement) and the
5th, i.e. 95% less than the mean, or in addition to 1.96 times the standard deviation. In
practice, the 5th and 95th percentile are used.
As can be seen from the diagram, there are further differences between the user
groups that must also be considered: differences in sex are especially important here.
Thus, a body height of an average female (50th percentile) corresponds to a rather
short male (5th percentile). Similarly, sex-specific differences also exist for other body
sizes and proportions. A mixing of data for females and males would not make sense
since the differences would no longer be sufficiently taken into consideration. Instead,
different analyses for product ergonomics are necessary.
For safety-relevant measurements the 1. or 99. percentile is usually used.
The values given in the table are based on statistically validated measurements of
persons from the Federal Republic Germany (DIN 33402).
In the industry, work materials and workplaces, whose measurements are to
correspond to the body dimensions of the person, cannot always be designed for
each individual user due to economic reasons. Therefore, it is necessary to establish
a basis for the adaptation of work materials and the workplace to the body form of as
many users are possible by using statistical data. Thereby, depending on task and
usage type, it is possible to attain different workplace sizes, adjustments or a design
applicable to all users.
Aside from differentiation between the sexes, differences between age groups,
regions and clothing must also be included. This is especially true for when products
are designed for global markets.
Region/Cultural dependencies of measurements: A 95. percentile Vietnamese, and
thus a notably tall man from this region, is approximately equal to a 10. percentile
central European. The range from the .5 to the .95 percentile man from the “South
East Asian” region amounts to 153-172 cm.
Also see: Sanders & McCormick, 1993, pp. 420ff
Through the course of time a general increase in body size, especially in industrial
nations, can be noted. This occurrence called the increase of body dimensions takes
place primarily due to improvements in living conditions (hygiene, nutrition, work
conditions).
An extrapolation for the adaptation of older tables or to the estimation of future ones
remains problematic since the increase in sizes do not occur continuously, and no
reliable prediction about a possible end of the increases is available.
However – as an example – increase of body dimensions was calculated up until the
year 2050 for the Airbus A380 so that passengers will still have comfortable seating
then. (Bauch, 2001, www.haw-hamburg.de/pers/Scholz/dglr/bericht0101/Bauch.pdf)
But the increase of body dimensions is currently changing: this graph shows exactly
this development of the mean body height for both countries (Germany and
Switzerland) starting in the 50ies.
Anthropometric data of military recruitment provides the possibility to analyse the
cumulative length and weight increase of young men between the age of 18 to 22
years with an representative sample every year. The analysis of N = 400.000 swish
data records from the time interval between 1992-2011 and N = 1.8 Mio. German
data records from 1984-1999 shows that the mean body height has increased about
approximately six cam (2.36 inch ) at about 178 cm respectively 180 cm (5.8 foot.).
However, recent data analysis showed that for both countries the height acceleration
currently stagnates. It is commonly assumed that the genetic maximum of human
growth seems to have been attained.
(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.
Height and corpulence
Body sizes are not independent of one another, rather, they strongly correlate with
each other. Body sizes within a group (e.g. high and long measurements as well as
reaches) possess a high correlation to one another, while the correlation between
body sizes of different groups is practically non-existent: not every large person is
overweight!
The statistical tool of factor analysis can be used based on the correlations in order to
combine similar sizes. In anthropometry something similar occurs through the use of
index values.
There are three types of body sizes: the body height, the corpulence and the
proportion (sitting giant/sitting dwarf).
An optimal product design takes into consideration not only small or large people
(height), but also the corpulence and proportions. Instead of two values (big, small)
there are actually 8:
Big, slender, short-legged
Big, corpulent, short-legged
Big, slender, long-legged
Big corpulent, long-legged
And the same for small persons.
Differences between sex and age group must also be considered.
Muscle force is a physical strength that works through the activity of the muscles
within the body. There is a difference between static and dynamic muscle force. Static
muscle force is the physical strength that occurs without a change in the length of the
muscle during its activity. Dynamic muscle force, however, occurs during the change
in length of the muscle in its activity.
Inertia force is a physical strength that works as a force of inertia, e.g. dynamically as
accelerating force, force of deceleration, or centrifugal force at mobile workplaces, or
statically as own weight.
Applied force is a physical strength that works outward from the body. It results from
inertia force, muscle force, or both. Inertia force and muscle force can reduce or
increase their strength depending on amount and direction.
From the force-releasing body parts the applied force is split into e.g. arm, hand, leg
or finger force; from the force direction the applied force is split into e.g. vertical or
horizontal force.
The applied force is differentiated according to the force of attraction and the force of
pressure from the sense of direction of force.
The specifications of DIN 33411-4 apply to an upright unconstrained body posture with non
shifted parallel foot position on a foot spacing of 30 cm. The given values of the maximum
static action forces were determined on fixed positioned handles with a short-term maximum
contraction force of the worker. A cylindrical grip was used with a diameter of 30 mm, which
has been operated without tools. These are average values of the maximum possible static
action forces that apply to certain collectives (e.g., men aged 20 to 25 years) and not
representative for the total population. The representation is in the form of isodynes. The
transferability of the data must be checked for differing operating situations (e.g. in terms of
posture or the required force direction). Maximum static action forces from other operating
situations for example are presented in DIN 33411-3 and DIN 33411-5.
Example: From a side angle ß = 30°, an elevation angle = 0° and a relative range a = 50% a
maximum driving force of F=150 N results for the vertical upward arm forces performed by a
male person.
Human action forces play a role for all mechanical performances. They occur during
the maintenance of body positions, during the execution of free or steered body
movements or its extremities, during the use of work tools, in the operation of
operating elements, or during the manipulation of loads. Physical strengths are
developed as muscular strengths within the body, work as mass force (force of
inertia) from the outside onto the body or are transferred by the body as action forces
to the outside.
Physical forces can be used for the design of work media for various goals. For
example, data collection from the viewpoint of comfortable usage could take place for
how to design the operating elements’ operational resistances that must be served in
an automobile. For the continuous manual regulation of dynamic processes, however,
the question remains regarding which level of operating resistance operating
elements must have in order to deliver an adequate proprioceptive (realisation of
stimuli arising from own organism) response about the movement procedure.
DIN 33411, Teil 1: Körperkräfte des Menschen – Begriffe, Zusammenhänge,
Bestimmungsgrößen (Physical strengths of man – concepts, interrelations, defining
parameters)
Maximum isometric forces (isodynes): DIN 33411, Teil 4, S. 1:
Also see: Sanders & McCormick, 1993, pp. 248-254
Dynamic (Functional) Dimension: Active area of the hand-arm-system
Aside from measures for the performance of functions (work areas, areas of joint
movement), safety measures (safety, minimum and maximum distances) and space
requirement measures (space requirements, compensational movement) can also be
differentiated between.
Aside from static anthropometry it is getting more and more important to account for
dynamics since in reality, postures are never static but always fluctuate around
average. Especially work is always bound to deliberate movements.
For movement planning, a comprehensive methodology to capture and document
data like in anthropometry is not available for yet. Whereas for anthropometry, it is
human body dimensions and corpulence within groups of people, there is not such a
thing for movements.
There is even a stronger diversification and variability of movements. Even the same
person does never move exactly the same way twice. So beside of the inter-individual
diversification, there is also an intra-individual one. Hence, for movement planning,
the ergonomic planner has to rely on estimations of spacial requirements or single
movement tracks.
A specific movement is partitioned into several phases. The actual movement first has
a design phase in which a movement pre-programming takes place. The movement
itself divides into two other phases: the ballistic and the visually controlled phases.
The first phase serves for quick guidance to the goal, while a fine-tuning occurs in the
second phase.
The temporal division of these two phases amounts approximately 2/3 to 1/3.
Approaches of varying complexity are available for the characterisation of movement:
Temporal and spatial characteristic data are easy to use, yet simplify a movement too
much and are therefore only suitable for narrowly outlined special areas (e.g.
methods-time-measurement or work-factor-processes in the scope of production
planning).
Motion paths, or trajectories, express spatial relationships. The problem is the
summarization and meaningful preparation and presentation of the multitude of
possible motion paths.
Biokinematic models are based on different approaches (e.g. biomechanic or inverse
kinematics) and allow an exact replication of individual movements for digital human
models or in simulations. However, the variability of the movements is also a problem
here. Still, due to their high level of clarity and face validity of presentations, they have
managed to be supported by all human models.
Fields of vision (upper left: different areas of the field of view – pay attention to colour
dependencies!) and thereby the recognisability and readability of instruments
(dependent on vision – Visus 1 (normal): 1 arc minute resolution) are at least equally
as important as anthropometry.
The design of vehicles begins with a fictitious eye-point (Design-Eye-Point, airplane)
or from an eye ellipse (auto) in which the eye of the future user exists.
Airplane (bottom left):
Design Eye Position (eye-point):
... Is a set point relative to the airplane structure upon which the eyes of the pilot
are to be in the normal seating position (SAE ARP 4202); fixing of the pilot’s
position in the cockpit; seating adjustment area is to be fixed so that all pilots can
attain positions in the DEP
Line of Sight
The line of sight provides the line of vision during landing; sloped downward (angle
of incidence during landing)
In practice, the verification of the sight requirements can also be done through lines of
sight in CAD or in technical drawings. It is easier to do so with human models (bottom
right) which present the fields of view as cones, or that directly calculate the view of
the user.
Somatography (Greek): sketching of bodies
In video somatography the video image of a test person is superimposed full-scale on a
drawing or a model of the workplace.
The test person can coordinate his/her movements through a control monitor (Luczak,
1998, p. 599f; Original in Martin, 1981)
Body templates exist for various body heights in front and side views as well as top view.
The indication of joint centre points allows an easy presentation of different body positions
for the verification of the design measurements of workplaces.
body templates: DIN 33408 Teil 1, also see: Pahl et al., 1996, p. 306; Pahl & Beitz, 1997,
p. 368; Luzak & Volpert, 1997, p. 382
somatography: Sanders & McCormick, 1993, pp. 419-420
physical models: Sanders & McCormick, 1993, pp. 422-423
(bottom left): Bosch Template – 4 simple templates for: 5. Perc. Female, 50. Perc.
Female/5. Perc. Male, 95. Perc, Female/50. Perc. Male, 95. Perc. Male. The rules of
technical drawings are in effect, therefore three-dimensional results in technical drawings
are also possible.
Significant simplification of the joints (point joints), but with indication of maximum angles.
(bottom right): Kiel Doll – 6 complex templates for 5., 50., 95. Perc. Female and Male. KD
available in side view for different measurements (standardised according to DIN 33408) .
Top view also available, though in practice barely used due to low practicality. Typical are
link joints for the shoulder, hip, and knee that make possible exact reaching range.
Limited applicability range since results only count for shoulder height, i.e. not movements
to the side (which is common in reality).
Today, digital human models have prevailed due to the spread of CAD. If full-scaled
CAD outputs are produced in the beginning stages into which templates are entered,
then in the digital human models body dimensions are directly taken into account in
CAD.
The human models contain databases with anthropometric measurements (body
dimensions, field of vision, joint angles, forces), a movement simulation and additional
analysis tools which make the analysis of reachability and vision, but also the
considerations of comfort, possible.
Depending on the model, two basic procedures can be derived:
1 – Model in CAD:
Here, the digital human model is integrated into the CAD environment (e.g. Anthropos
in CATIA). The geometry of the product does not first have to be exported and
transformed, rather, it is already complete and in the correct layer format. Changes
can be made directly in the primary version of the design. The advantage is that no
losses occur during the transfer of the design into other CAD environments, and
changes are integrated. A disadvantage is that a slower calculation of the CAD model
occurs which was only implemented here as a model of the CAD environment.
2 – Design analysis in the human model environment
The design is exported (partially) from the original CAD environment and then
imported into its own human model environment (with significantly less options than in
CAD). The analyses are then conducted here. The advantage is a faster calculation
(since the entire CAD environment is already running in the background). A
disadvantage, however, are problems in the transfer of the design from CAD into the
human model.
Here is an example for the general procedure of anthropometric product design
Generation of the first human model:
Basic options (left):
(1) Generation of the first representative human model via a database query
(common in human model). Important during this procedure is the relationship to the
user group, i.e. differentiation according to sex, nation, age, increase of body
dimensions, increase in height, corpulence and proportion
OR
(2) Generation of own human model based on anthropometric dimensions. The model
is hereby extrapolated and calculated through the input of a variety of different
reference dimensions.
The model along with the (simplified) product design are then presented in an
environment.
In the second step the task and the restrictions are defined:
1. The posture is determined according to inputs of the seating reference point/hip
point and the incline of the seat/backrests.
In addition, contact surfaces and the positions of the operating elements are
determined and then entered into the human model.
2. Next, the body parts and the posture (e.g. contact or gripping grasp) are
determined.
3. Finally, the animation (calculation of the posture) takes place via the human model
along with the first visual plausibility test.
“Simple” analyses such as fields of vision and spaces within reach/reachable areas
are then carried out by the model. Fields of vision are shown as cones for “outsiders”
as well as for the particular model.
Through a change in the model a plastic impression of the future view is attained.
Spaces within reach can be directly presented for the planning ergonomics, and can
thus be take into consideration by operating elements.
For ergonomics of testing the reachability of operating elements can be directly tested
by entering tasks (see previous slide). In this case the proper posture is also
accounted for.
Important: CAD environments allow for a preferred level of accuracy in such
examinations (1/10. mm are not a problem). However, the anthropometric data as
well as the posture data are not as accurate. In practice, especially for spaces within
reach or collisions with the product, safety margins of at least 1 cm should be used.
The analysis of posture comfort is more complex. Height as well as body dimensions
(these are of a general nature and independent from the product), joint angles (these
are depending on the product) and forces on the joints (details) are included in this
analysis.
By regression respectively comfort models it is possible to get a value of (dis-)comfort
out of the input values.
IMPORTANT: Do not simply follow these instructions without being critical. Instead,
check for which boundary conditions discomfort calculations were validated. Thus,
vehicle considerations (e.g. automobile manufacturing) cannot be taken over by all
areas (e.g. maintenance) without problems - particularly problematic are the
differences in posture (sitting/standing). A transfer here is impossible.
An uncritical reliance on data leads to errors!
With an individual model no user collective can be reproduced. Hence, the analyses
are to be repeated with additional models. Depending on the complexity of the
collective this may encompass more than 10 models. This is the only way that
problem areas (see slide’s head collision of large man of medium corpulence and
medium proportion) be identified and corrected.
These pictures show that the simulated movements and postures of mannequins
cannot simply be used without limitation for the design of products. Several
misinterpretations can be seen that are shown through the movement apparatus and
the theoretically allowable degrees of freedom, and which are theoretically acceptable
according to the mathematical relationships of the human model, but which cannot
actually be captured by a human.
This is especially true for the body angles or torsions and the penetration of adjacent
objects.
RAMSIS is the 3D CAD ergonomics tool. Package and design studies during the
design phase of a vehicle can be extensively processed with RAMSIS. RAMSIS is the
global leader of CAD tools for ergonomic design and analysis of vehicle interiors and
workplaces and is used by more than 60% of all automobile producers.
Advantage: Extensive analysis is already possible in the pre-production phase without
requiring building of expensive physical models. (also see Luczak & Volpert, 1997, p.
383f)
Anthropometric Database 90 real, statistically validated body types
Standard animation: Translation/rotation interactively or numerically, joint animation
numerically or interactively, fast automatic target point animation for freely definable
chains of body parts, interactive drawing of body part chains, analysis of spatial
coordinates and joint angles
Restrictive animation: Marginal posture calculations, body type independent task
description, interactive goal definition, consideration of interfaces, tangential ability
requirements, consideration of self-intersection
Health and comfort analysis: Analysis of posture comfort, posture-dependent body
part comfort evaluation, fatigue analysis, orthopaedic evaluation of spinal curvature
Vision analysis: Incorporation of eye, head and neck movements into restrictive
animation, internal sight, ergonomic evaluation of the field of vision, consideration of
focal distance, simulation of mirror view
Belt analysis: Calculation of belt routing, calculation of seatbelt points
Reachability Analysis: Body type-dependent calculations of reachability levels, (also)
for extremities, calculation of reachability surfaces for body part chains.
The human body model JACK‘s main background is in computer graphics , for
example in animation of virtual humans in movies. In anglophone countries, it is also
used for product design (primarily automotive) and as tool for educational training
movies.
Main objective of JACK today is beside of product design also the display of humans
in virtual environments. With special hardware, JACK is kind of remotely controlled
and follows the real human‘s movements. When aditionally displaying the virtual sight
of JACK, the user gets the impression of personally sitting in the vehicle. This makes
very early and detailled product analysis possible.
The database of body measurements is primarily based on US-American data sets.
They are represented as percentiles. JACK offers functionality for analysis of sight,
range, postures and movements.
Delmia (Digital Enterprise Lean Manufacturing Interactive Application) by Dassault
Systems is a software for planning, visualisation, simulation and validation for
production planning. Delmia is making first attempts to pursue the idea of digital
manufacturing and includes an integrated human model, DELMIA human.
Focus of development has been to model body measure variabilities for vehicle
interior design. Similar to RAMSIS, there an exhaustive methodology which by far
exceed simple percentile measures.
Existing analysis caapabilities comprise vision, reach, postures and movement
analysis. Additionally, there are functionalities to execute methods-time-
measurement, force and performance analysis.
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