Abstract
When a robot manipulator contacts objects, the contact force between the robot hand and the object as well as the position of the robot hand must be controlled in many tasks. In the previous works of hybrid position/force control, it was assumed that the mechanical constraint condition was exactly obtained or the constraint surface or the constraint line was exactly expressed by geometrical equations. In practice, however, the parameter values of geometrical equations, kinematic and dynamics of the robot contain estimation errors. This paper describes position/force trajectory tracking feedback control performance of robot manipulators under parameter estimation error. It is mathematically proven that the trajectory tracking performance can be improved by setting suitable combination of the feedback gains even though all parameters contain estimation errors.
