Quadrupedal running at high speed over uneven terrain

High-speed legged locomotion is complicated by the challenge of uneven terrain because the system must respond to the fast-changing terrain elevation under each foot, and quickly secure a solid foothold after touchdown. This paper presents a leg stretch reflex and anti-slip retraction algorithm that are added to a previously presented controller to stabilize a high-speed trot over uneven terrain. Together with fuzzy control and a force redistribution algorithm, these control mechanisms stabilize a quadruped trot at 5.25 m/s. The quadruped can turn at 30 deg/s when running at 3.0 m/s, and can maneuver over uneven terrain with standard deviation of height variation of 3 cm at 4.0 m/s. This appears to be the first reported control of high-speed quadrupedal running over uneven terrain.