Underactuated Motion Planning and Control for Jumping with Wheeled-Bipedal Robots
This research provides a method for wheeled-bipedal robots to perform jumping motions, which could be significant for improving the mobility and versatility of these robots in complex environments.
This paper addresses the challenge of underactuated motion planning and control for wheeled-bipedal robots to enable jumping. It proposes a novel wheeled-spring-loaded inverted pendulum (W-SLIP) model and a quadratic programming-based solution for planning, combined with a LQR-based wheel controller and a task-space whole-body controller for accurate trajectory tracking.
This paper studies jumping for wheeled-bipedal robots, a motion that takes full advantage of the benefits from the hybrid wheeled and legged design features. A comprehensive hierarchical scheme for motion planning and control of jumping with wheeled-bipedal robots is developed. Underactuation of the wheeled-bipedal dynamics is the main difficulty to be addressed, especially in the planning problem. To tackle this issue, a novel wheeled-spring-loaded inverted pendulum (W-SLIP) model is proposed to characterize the essential dynamics of wheeled-bipedal robots during jumping. Relying on a differential-flatness-like property of the W-SLIP model, a tractable quadratic programming based solution is devised for planning jumping motions for wheeled-bipedal robots. Combined with a kinematic planning scheme accounting for the flight phase motion, a complete planning scheme for the W-SLIP model is developed. To enable accurate tracking of the planned trajectories, a linear quadratic regulator based wheel controller and a task-space whole-body controller for the other joints are blended through disturbance observers. The overall planning and control scheme is validated using V-REP simulations of a prototype wheeled-bipedal robot.