上海科技大学知识管理系统

Bounding gaits, with their symmetric property and robustness, have great potential in performing high-velocity locomotion. Generally, legged animals, such as cheetahs, position their torso in a non-zero pitch angle to gain acceleration before pouncing. Inspired by this phenomenon, we explore the influences of pitch angle on the bounding velocity using the simulation of an MIT mini-Cheetah. We first model the pitch angle based on robot dynamics and then compare performances via simulation. The pouncing process is divided into the activation phase and acceleration phase. The pitch angle is designed specially for each phase: for the activation phase, we initialize a non-zero starting pitch angle and define a decay function for it to decrease into a suitable range; for the acceleration phase, we use a trigonometric function to model the periodic desired pitch angle in one gait cycle. Our simulation shows that the new design, with a non-zero starting and desired pitch angle, reaches a 40% higher maximum velocity than the original algorithm, with a zero starting and desired pitch angle. This points to the possibility of improving the velocity of legged locomotion with minor changes in the initial states of a robot.