Implementation of a Versatile 3D ZMP Trajectory Optimization Algorithm on a Multi-Modal Legged Robotic Platform

This paper presents a multi-functioning light weight robotic system, the Autonomous Legged Personal Helper Robot with Enhanced Dynamics (ALPHRED), capable of both locomtion and manipulation. In addition, we extended a 2D zero moment point (ZMP) trajectory optimization (TO) algorithm to a 3D implementation. As well as adding the acceleration of the center of mass to the TO cost in order to smooth out the motion of the robot during trajectories with support polygons that do not intersect. By implementing this versatile TO algorithm on a multi-modal robotic platform we showed that many different forms of stable locomotion and manipulation were possible including a dynamic 0.7 m/s trot gait.