DYNAMICS FOR DUAL-ARM FLOATING SPACE ROBOT WITH CLOSED CHAIN AND ADAPTIVE CONTROL FOR OBJECT MOTION WITH LIMITED TORQUE

Dynamic and adaptive control problems for a floating dual-arm space robot transferring a target with limited inputs are discussed. Based on the Lagrange method, the dynamic model of an open chain space robot is established. Then, with closed-loop constraints in a closed chain system, a dynamic model of a dual-arm space robot system is obtained. Upon this basis, adaptive control is proposed for the closed chain system, considering uncertain parameters, external disturbances, and limited inputs, to complete the accurate control of load position and attitude. The input torque is limited by a control law with a saturation function. The uncertainty of the system is estimated by an adaptive controller. The velocity and angular velocity of the system are estimated using a high precision filter, requiring only the feedback position and the angle of the system. The stability of a closed chain system is proved via the Lyapunov Method. At last, numerical examples simulate the process of a planar dual-arm space robot transferring a target and verify the efficiency of the control scheme.