A bilateral teleoperation method using an autonomous control based on DFT modal decomposition

In these days, bilateral control is utilized for various scenes such as remote surgery, work in the space, nuclear plants, and so on. But in these cases, there is a dangerousness, for example a fragile organ. These environments are able to be broken or lost its plastic behavior with the excessive force. So there is a necessity to avoid this excessive force. This paper proposes a method of autonomous hazard avoidance control based on DFT modal decomposition. This control system consists of bilateral control based on acceleration control with disturbance observer and variable compliance control. During safe operation, bilateral control works and during dangerous operation, the control so as to avoid dangerous operation works. In order to decide the degree of operation risk in slave side, fuzzy algorithm based on the grasping force added to the environment is utilized. And in order to extract the grasping force, discrete Fourier transform is utilized. If the operation is dangerous, operator feels the force to adjust excessive grasping force to the proper grasping force by the force filter. The validity of the proposed method is confirmed by the experimental results.