Slope-walking of a biped robot with position and orientation based inverse kinematics method

Abstract

This paper proposes a slope-walking strategy of a bipedal robot using position and orientation based inverse kinematics method. Some researchers implemented control approaches to solve this problem. Generally, they apply control feedback at ankle joints and introduced many more control methodologies. Several researchers used pelvis and foot trajectories without showing center of mass trajectory. In this paper, a constant center of mass height trajectory of a biped robot during slope walking is ensured. Inverse kinematics methodology is introduced systematically for bipedal walking on inclined floor. Positions and orientations are embedded into the kinematics calculation. In this strategy, walking pattern for flat floor must be developed first. Then, the same walking pattern can be used for the inclined floor with orientation included so that the bipedal robot is able to walk on the inclined floor successfully. This methodology will distribute the angles caused by the inclined surfaces to the appropriate robot joints. By doing this, control at ankle joints only is avoided. 3-D dynamics simulator, known as Robot Control Simulator is used for simulations in order to validate our proposed method. Simulations of biped walking on 11° slope with our proposed method have been done.