Transition from free motion control to constrained force control for robot manipulators

An adaptive control strategy with direct force feedback is proposed to control robot manipulator moving from free-space to collision with the environment and then tracking a given trajectory on the contacting surface. The collision dynamics, modelled using impulsive force, was studied. The frictions between the robot and environment surface, which have strong effects especially at low velocity, have been investigated. A simulation-based case study is undertaken to justify the control strategy proposed.