Investigating motion and trajectory forms of a wheeled mobile robot on a flat surface with an inclination angle

PEOPLER-II is a hybrid robot with 8-leg ends and 4-wheels attached to a knee joint rim rotating around a hip joint. It has been developed to assist people who needs enhancement for their capability of locomotion. In order to cope with different environments, investigation of the robot trajectory is of significant importance while a frictional condition of the surface influences the form of trajectory. Therefore, this paper extends a C++ object oriented simulator based on mathematical expression for estimating energy cost of motion utilizing the Principle of Virtual Work to the wheeled locomotion mode of the PEOPLER-II. We clarify the robot trajectory form of turning and spinning. Actually, we demonstrate the simulated trajectories on flat surfaces. In addition, we show the effect of the velocity ratio between right and left side wheels on the trajectory forms as well as the inclination angle of the surface.