Adaptive force/position control of a robot hand

Abstract

Presents a position/force control algorithm for a robot hand grasping a flexible object. The adaptive control algorithm of Slotine and Li (1991) is employed for realising an adaptive position controller for the variation of masses of the fingers during unconstrained movement. A PI nonlinear force controller modifies the position trajectory until the contacts reach the objects to be grasped. The controller parameters are adjusted for minimising the rebounding produced by contact between the hand and its environment. A task planner permits the automation of the motion of the controllers and the processes of grasping the object. The simulation results of a three fingered hand demonstrates the stability and effectiveness of the controllers in the presence of surface impedance variation and kinematic error modelling.