A Stable Docking Operation by a Group of Space Robots

This paper presents an attitude control strategy in the three planar space robots having two DOF for docking operation of a free flying hexagonal object using the bond graph technique for modeling and simulation. As the highly non linearity, strongly coupled and non-holonomic characteristics of a free flying space robot, the position and posture of the base body changes when the free floating space robot is moving its manipulator to the position to capture a target. As the base of space robot is not fixed, it gets disturbed while docking operation in the absence of attitude controller. Therefore, it is a great challenge to control the base disturbance. To minimize this problem, dynamic model of the three space robots is proposed. The simulation results show that the attitude disturbance is minimized by using three space robots in place of the two space robots keeping all parameters same. Keywords— free flying object; space robot; attitude control.