Abstract
In this paper, we deal with a three-link space robot moving in planar space without controls for the base attitude. An experimental setup of the three-link space robot can levitate by use of compressed air. Using d'Alembert principle, it is shown that the state equation of the three-link space robot can be reconstructed as a first-order nonholonomic system with the constraint condition that the rotational angle of the base is set to be zero. The feedforward torque inputs can be obtained by the final-state control in order to bring the end effector of the space robot from the initial position to the objective position in the desired time. We designed a two-degree-of-freedom control consisting of feedback control and feedforward control to follow the obtained trajectory. It is verified from simulation and experiment that the proposed method of motion control is useful.
