Elliptical motion method for robust quadrupedal locomotion

In this paper we present a new elliptical motion method that allows integration of different walking gaits with Jacobian-based robot body kinematics. Implemented walk and trot gaits are controlled with a central pattern generator (CPG). By combining these gaits with robot kinematics, robot pose control is enabled during robot motion. The proposed method generates the elliptical type of foot motion independently of possible robot pose changes, which makes robot locomotion very robust to various disturbance effects (e.g. impact of uneven terrain, external forces, and sensor-guided changes of robot posture). The method was implemented and tested on the 13 degrees of freedom (DOF) four-legged robot. The results have confirmed that the robot maintains the desired walking gait while changing its pose in accordance with a task being executed.