Page 84 - Mechatronics for Safety, Security and Dependability in a New Era

Ch15-I044963.fm Page 68 Tuesday, August 1, 2006 12:58 PM
Ch15-I044963.fm
68 68 Page 68 Tuesday, August 1,2006 12:58 PM

description of musculoskeletal human bodies.

Measureing
Subjects'
Physique

fModel-based^ Visualizing
Motion Evaluation/
Evaluation/ Simulation
Simulation J Result
Figure 1: Concept of Info-Ergonomics Simulation System
2. INFO-ERGONOMICS SIMULATION

As mentioned above, Info-Ergonomics is a concept which can simulate pain/fatigue on
computer-based human mockup model. The basic idea of Tnfo-Ergonomics established as a
wide-range application of Real World Database (RWDB) system [1]. RWDB is integration of 4
component of technologies, Video Capturing, Model based Analysis, Database Processing and
Computer Vision. Similarly in the Info-Ergonomics Simulation, Capturing human body motion,
Human model creation, Model based analysis/simulation and Visualization are fundamental
technologies. This concept is summarized in Figure 1. The function and target of each module is as
follows.
• Measuring subjects' physique
In order to evaluate/simulate human body motions precisely, customized human body model
must be required. When measuring subjects' physique, not only body size but the body
characteristics (range of motion, muscle strength, and so on) should be included.
• Motion capturing
Camera-based motion capture system is adequate because it can detect human posture at each
time point without disturbance.
• Model-based Motion evaluation/simulation
Using the customized human model mentioned above, load/fatigue estimation must be done
in musculoskeletal level for each time-point-posture of a work motion, provided by motion
capturing system.
• Visualizing Evaluation/Simulation result
In order to help intuitive understanding of simulation/evaluation result, some 3D CG systems
which can display all bones and muscles with textures in real-time way are required. Also,
coloring bone/muscle segments depending on pain/fatigue level is highly recommended.
When we realize total system, we must develop each device, software, and design data format in detail.
Especially the data format which bridges functions and functions has an important role. As a result,
total system has been designed as a data flow map as shown in Figure 2.
Detail functions of major boxes will be discussed in later sections.

3. PRECISE HUMAN MODEL AND THE DESCRIPTION METHOD

Tn order to achieve precise evaluation/simulation reflecting individuality( body size, flexibility,
physical condition and so on), creating precise human-mockup is the most important issue. However,
as human body has a very complicated structure, it is impossible to implement all factors of human
bodies such as bones' shape, positions to connect bone and muscle, maximum muscle force, and so on.
Therefore selecting essential parameters to execute human simulation and the measurement methods
of those parameters should be considered keenly. Also, another important issue is the description
method of individual human body, i.e. model description methodology.
From now on, we will be focusing on core technologies and data format to descirbe measurement