Integrating Trajectory Optimization and Reinforcement Learning for Quadrupedal Jumping with Terrain-Adaptive Landing

Abstract-- Jumping constitutes an essential component of quadruped robots' locomotion capabilities, which includes dynamic take-off and adaptive landing. Existing quadrupedal jumping studies mainly focused on the stance and flight phase by assuming a flat landing ground, which is impractical in many real world cases. This work proposes a safe landing framework that achieves adaptive landing on rough terrains by combining Trajectory Optimization (TO) and Reinforcement Learning (RL) together . The RL agent learns to track the reference motion generated by TO in the environments with rough terrains. T o enable the learning of compliant landing skills on challenging terrains, a reward relaxation strategy is synthesized to encourage exploration during landing recovery period. Extensive experiments validate the accurate tracking and safe landing skills benefiting from our proposed method in various scenarios. I. INTRODUCTION With the development of the legged robot community over several decades, the locomotion performance of quadruped robots has improved remarkably, including but not limited to traversing the wild and performing robustly against disturbances [1], [2], [3], [4], [5], [6], [7], [8], [9].