Hi everyone: I've contacted Mr. Tang. (skype : tangxc@gyems.cn ) I get quick responses on skype. Mr. Tang recommends us to ask him questions on skype. As for the problem above. Myactuator GUI 2.1 is not for some type of motor. We have to use this one: there are two files inside. one is the suitable GUI, the other is the driver for UART. As for the torque problem. I thought the torque was weak because no matter what torque command is, the speed limit is the same. That's why no matter what torque value we command, the outcome looks the same, it's spinning at a same speed. As long as I connect it to the suitable GUI, I can easily tune the torque value, I find a way to measure the real torque output, and it works just fine, it does answer to my torque command. The way I measure the torque is to lock a long bar on the rotor, and measure the force vertical to the bar at the edge of the bar.