Synthesis and Analysis Techniques for the Human Body: R&D Projects - 3D Modeling and Animation: Synthesis and Analysis Techniques for the Human Body - page 350

Figure 2. Joint kinematics. Left: Hip joint during a motion of flexion; Right:
Knee joint flexion. Helical axes of motion are displayed, as well.
Kinematics is the study of motion. As part of the VAKHUM project, the motion
of the human lower limb will be studied during several normal activities (walking,
running, stair climbing). Several techniques can be used to study a motion, each
of them having its own advantages and disadvantages. This data, associated with
medical imaging, can bring forth new information on human kinematics (Figure
2). Unfortunately, electrogoniometry is difficult to use to study full-limb motion.
Other systems like motion-capture-devices using stereophotogrammetry (e.g.,
video cameras) allow us to study the relative angular displacement of the joints
of a particular limb by tracking skin markers attached to a volunteer or patient
during some activities (Figure 3).
VAKHUM deals with combining electrogoniometry and stereophotogrammetry
to animate 3D models collected from medical imaging. This technique allows not
only a combination of different data sources, but also a comparison of results
obtained from different protocols, which currently poses an accuracy problem in
Figure 3. Left: Anatomical calibration of skin markers for gait analysis;
Right: Kinematics analysis of stair climbing.