Abstract: In this paper, the problem of compliance control of a robot manipulator is studied. To realize hybrid control, the dynamic equations of mamipulators are set up by a couple of what is called "task specification project operators", and two design methods of hybrid position/ force controller are proposed to guarantee accurate tracking of the desired motion and force: one is given by means of the computed torque method and the other is variable structure control. It is shown that robustness has been improved in the latter case.