Apex height control of a two-mass hopping robot

摘要

The spring loaded inverted pendulum (SLIP) model is commonly used to describe the dynamics of hopping robots. Based on this model, the control of hopping robots has been widely investigated. A fundamental limitation of the model is that it fails to account for impact with the ground, and this is due to its single degree-of-freedom in the vertical direction. A more accurate representation of the hopping robot is proposed using a two mass model and inelastic impact with the ground. A control scheme is developed to converge the maximum jumping height of the robot to a desired value. The control scheme utilizes feedback linearization in continuous time and updates a control parameter in discrete time to achieve the control objective. Simulation results are presented to show the efficacy of the control scheme.