DYNAMIC CONTROL OF FREE-FLOATING COORDINATED SPACE ROBOTS

The position and force control of coordinated robots mounted on spacec raft, manipulating objects with closed kinematic chain constraints, re presents an important class of control problem. In this article, the k inematics and dynamics of free-floating coordinated space robotic syst em with closed kinematic constraints are developed. An approach to pos ition and force control of free-floating coordinated space robots with dosed kinematic constraints is proposed for the first time. Unlike pr evious coordinated space robot control methods which are for open kine matic chains, the method presented here addresses the main difficult p roblem of control of closed kinematic chains. The controller consists of two parts, position controller and internal force controller, which regulate, respectively, the object position and internal forces betwe en the object and end-effecters. The stability of the closed-loop coor dinated robotic system is analyzed using the error models of the objec t position and internal forces. It is proved that the errors in the ob ject position and internal forces asymptotically converge to zero unde r the assumption of exact kinematic and dynamic models. (C) 1998 John Wiley & Sons, Inc.