The dynamic instability problem exists in，the force control of robot manipulator，which is the contradiction between response speed and stability. For the sampling control system，the accelerations positive feedback in task space can broaden the system frequency band and raise the system damping. This approach can enhance the robot manipulator's ability to adapt itself to the stiff environment and relax the dynamec instability problem in force control obviously. In addition，this article discusses the prospective application in using the integration of the filtered integral signal of the accelerator and the encodes' signal to replace the velocity coming form the position defference to remove the difference noise and improve the precision in force control of robot manipulator.