Impedance Control of Space Robots Using Passive Degrees of Freedom in Controller Domain

Abstract

Impedance control is an efficient and stable method of providing trajectory and force control in robotic systems. The procedure by which the impedance of the manipulator is changed is a very important aspect in the design of impedance based control schemes. In this work, a scheme is presented in which the control of impedance at the interface of the end effector and the space structure is achieved by introduction of a passive degree of freedom (DOF) in the controller of the robotic system. The impedance is shown to depend upon a compensation gain for the dynamics of the passive DOF. To illustrate the methodology, an example of a two DOF planer space robot is considered.

Bond graph modelling of a hydraulic cylinder-actuated planar manipulator

“…Moreover, it allows recognition of the nonlinear characteristics of different components, makes the models of the components reusable, and enables one to make a key check on the correctness of the basic equations. Bond graph, which was established by Professor Henry Paynter in 1961 [6], is one of the popular interdisciplinary approach of multiport modelling and it has encouraged research in numerous subfields [7][8][9][10][11][12][13]. Bond graph can represent the interactive dynamics of different Abstract In bond graph approach, the prismatic joint of hydraulic cylinder is usually modelled as two interconnected links (i.e., cylinder barrel and piston rod) constrained to produce the linear sliding motion.…”

Interaction Torque Control by Impedance Control of Space Robots

“…The concept of virtual foundation is discussed in [11]. It is presented in short here for ready reference.…”

“…This paper presents a torque control strategy using impedance control at the interface of the end-effector and a space structure. The impedance control is achieved by the introduction of passive degrees of freedom called virtual foundation in the controller of the robotic system [11]. When torque control is achieved, the vehicle attitude changes.…”

Adaptive Robust Controller For A Constrained Free-Floating Space Manipulator

“…In these constrained systems, forces and moments generated between the end-effector and the target must be controlled, rather than being treated as disturbances and rejected. Impedance control has been applied in [8,10,11] to solve this problem.…”