Abstract: Two robot force control systems were analysed with the Lagrange dynamic equations.In system Ⅰ,whichwas comprised of MANIPULATOR-FORCE SENSOR-WOPIECE,the force signals measured by the forcesensor was given to the manipulator controller to drive the end-effector of the manipulator to the final posi-tion.In system Ⅱ,which was comprised of MACRO/MICRO-FORCE SENSOR-WORKPIECE,a gross mo-tion was implemented by the MACRO.Then the MICRO regulated the end-effector of the manipulator toreach the final position according to the force feedback signals.It is shown that system Ⅱ was more stablethan system Ⅰ.