Area-oriented coordinated trajectory planning of dual-arm space robot for capturing a tumbling target

Abstract

The growing amount of space debris poses a threat to operational spacecraft and the long-term sustainability of activities in outer space. According to the orbital mechanics, an uncontrolled space object will be tumbling, bringing great challenge to capture and remove it. In this paper, a dual-arm coordinated “Area-Oriented Capture” (AOC) method is proposed to capture a non-cooperative tumbling target. Firstly, the motion equation of the tumbling target is established, based on which, the dynamic properties are analyzed. Then, the “Area-Oriented Capture” concept is presented to deal with the problem of large pose (position and attitude) deviation and tumbling motion. An area rather than fixed points/devices is taken as the object to be tracked and captured. As long as the manipulators’ end-effectors move to a specified range of the objective areas (not fixed points on the target, but areas), the target satellite will be hugged by the two arms. At last, the proposed method and the traditional method (i.e. fixed-point oriented capture method) are compared and analyzed through simulation. The results show that the proposed method has larger pose tolerance and takes shorter time for capturing a tumbling target. Keywords: Area-oriented capture, Dual-arm coordination, Space debris removal, Space robot, Tumbling target capturing