Abstract
In this paper, we discuss a posture control problem of a 2-link acrobat robot with nonzero initial angular momentum. First, we derive a strict feedback system by a coordinate transformation. Then the control problem is formulated as designing a control law such that the state variables of the system go to the origin at a given time. Next, the control law of the driving torque is designed by applying a backstepping procedure to the system. It is shown that the control performance and input efficiency are improved by using time-variant gains. Finally, simulation results are presented to show validity of the proposed controller.
