Abstract: A force feedback haptic device with a large workspace is developed for space teleoperation tasks, and the motion of the device in 3 directions is decoupled from each other. The velocity isotropic index and force isotropic index are analyzed through the Jacobin matrix. On this basis, a velocity control algorithm based on interaction force signal is proposed. Force signals for each axis are acquired in real time to estimate the magnitude and the direction of force exerted by the operator. And then the difference between the desired force and the acquired interaction force data is taken as the input of the PID (proportional-integral-derivative) controller. The PID control algorithm is used to control the motor speed. A proper data is given to control the motor to accomplish the movement. Experiments are conducted on a prototype mechanism. The results show that the proposed method can achieve better control results.