Three-dimensional motion analysis of upright bipedal walking android model

Area of Science:

• Robotics
• Biomechanics
• Human Gait Analysis

Background:

• A bipedal android model driven by trunk motion via psoas major contractions was previously developed.
• A mechanically stabilized principle model was created to preserve gait mechanics and enable autonomous bipedal walking.
• This model addressed knee and foot-ankle joint instability for reliable center of pressure measurement.

Purpose of the Study:

• To investigate if the center of pressure (COP) trajectory generated by a trunk-driven bipedal model approximates that of humans.
• To compare the COP trajectory of the principle model with that of healthy human subjects.

Main Methods:

• Utilized a three-dimensional gait analysis system.
• Attached 35 markers to healthy subjects and 24 markers to the principle model.
• Captured and analyzed ground reaction force data, comparing the right foot's COP trajectory during the stance phase.

Main Results:

• COP trajectories were generally similar during double-limb stance and single-limb support phases.
• The principle model exhibited a backward deviation of COP during single-limb support.
• Differences were attributed to shorter stride length, slower walking speed, and prolonged single-limb support in the model.

Conclusions:

• The principle model demonstrates trunk-driven motion with passive leg swing, partially replicating human COP trajectories.
• This contrasts with conventional gait analysis assuming passive trunk motion.
• A trunk-driven approach may offer valuable insights for robotic gait analysis and biomechanics.