抄録
A new model-based adaptive control method for a class of robot manipulators whose end-point is moving in touch with a geometrically constraint surface is proposed. A contact force arises at the end-point of the manipulator. Therefore, the manipulator is controlled so as to track both the desired end-point trajectory given on the constraint surface and the desired contact force trajectory simultaneously.
The method is based on the model-based adaptive law that estimates unknown or uncertain physical parameters of the manipulator such as mass, inertia, etc., and constructs the control input by using the estimated values of these parameters. The position and force control of the manipulator is realized in the joint-angle space by orthogonalizing the position and velocity error vectors to the contact force error vectors through introduction of a projection matrix that projects vectors in the joint space to the tangent plane of the constraint surface.
The convergence of position and force trajectory errors is theoretically proved. In addition, computer simulation results are given to show the convergence of these trajectories and to demonstrate the effectiveness of the proposed method.
