Abstract
This study discussed a generation of wheel gait for planar 4-DOF compass-like biped robot. Wheel gait is a novel locomotion pattern in which the stance leg swings in the opposite direction to that of a normal gait; that is, both the stance and swing legs rotate in the same direction. We derived dynamic equations of the robot and built an output tracking control of the hip angle. Next, we searched for fixed points using a numerical approach, and revealed that it is possible to generate a steady wheel gait on a slope with appropriate initial states. However, since the limit cycle around the fixed point was identicied to be unstable, it is expected that achieving a stable wheel gait with the control method in the real world is nearly impossible. On the other hand, small regions near the fixed point were found where stable period-2 gaits emerge, pointing to the possibility of stable wheel gait generation.