An online ergonomic evaluator for 3D product design

SpinFire TM SDK.Theresultisthencombinedwiththe
anthropometrical data comprising the digital human in
use and sent over to the pose generator for determining
the value of the corresponding joint angle (the hip angle
in this case). The similar procedure must be applied to
produce all the required joint angles, including elbow,
shoulder, hip, knee, ankle, and toe. The system then
transmits these parameter values along with the
anthropometrical data over to the back end ergonomic
evaluation engine over the Internet. The engine can thus
calculate forces/stresses for various body joints in the
given posture and design settings. The server prompts
the user in real-time with a new page containing the
evaluation result (see Fig. 8), and thus, helps determine
whether the current design needs further improvement.
4.2. Scenario II
Online customization of car interior design using
3D human model is another good application of the
proposed idea. The main screen designed for running
this scenario consists of three modules, similar to that
of the first scenario, as shown in Fig. 9. The left
module provides the user drop down lists for selecting
a specific digital human model for the current use. The
middle area contains a 3D display space of the viewer
and a history data access area. The user can adjust the
interior design through the UI’s in the right module
(R). A typical operational procedure consist of:
C.-F. Kuo, C.-H. Chu / Computers in Industry 56 (2005) 479–492 487
Fig. 8. Evaluation results for various joints generated from the ergonomic engine.
(1) Choose an interior design from the drop down
menu in middle module.
(2) Determine a digital human model that fits the user
best.
(3) Generate preferable 3D views and record them for
future evaluation.
(4) Adjust the car setting according to the digital
human.
(5) Perform the ergonomic evaluation described in the
first scenario if needed.
Similar to the first scenario, the user has to choose a
design model from the CAD database. The system
then automatically constructs a 3D digital human according
to the chosen anthropometric data. Currently,
the available options include: gender (male, female)
and the figure size percentage (95, 90, 50, 10, and 5%).
The model of a full-scale 3D human is thus imported
from the pose generator into the viewer. Fig. 9 demonstrates
a Taiwanese male with a 50% percentage
line. In contrast, a female with a 90% percentage line
is shown in Fig. 10. Note that the imported models
have been converted into the .3D format, which has a
small file size and easy to be transmitted and graphically
manipulated in a browser environment.
In theory, the car interior setting must fit the digital
human as close as possible to create comfort at a given
pose. The user can interactively adjust the seat setting,
mainly controlled by the seat angle and the steering