To whom it may concern,

I meet a problem when I use the forcemode() function provided by the rtde. When I use the default gain and damping in the force-mode, the TCP also shakes during the contacting with the environment. The shaking frequency is around 2-3 Hz. Then I try to tune the value of the gain and damping. However, the explain provided by the rtde is not enough for me to how these parameters work? I set the damping=1 and the gain=0.02. It won't shake anymore? However, the speed to approach the contacting surface is very slow.

All I can obtained form the rtde is that "A value of 1 is full damping, so the robot will decellerate quickly if no force is present. A value of 0 is no damping, here the robot will maintain the speed." and "A value larger than 1 can make force mode unstable, e.g. in case of collisions or pushing against hard surfaces." However, it is not enough to support me tune the parameters. Could you give me suggestion about the meaning of these parameters? Besides, in this hybrid control, the contact force is controlled in a direct force control way or controlled with admittance control?

Bests,

Yan