Admittance Separation Method for Admittance-Based Bilateral Control

Admittance-based bilateral control is reported to have the same performance as 4ch bilateral control with only force communication. However, admittance-based bilateral control was easy to vibrate when in contact with the hard environment. Previous studies did not assume the contact vibration. Damping injection is one of the effective methods to suppress the vibration, however it generates the extra operational force proportional to velocity. Thus the operability deteriorates. To suppress the contact vibration, this paper proposed admittance separation method. This method used different admittance values for position control and acceleration feedforward. Making a smaller values of admittance for position control is effective in suppressing vibration when in contact with the environment. Moreover, the extra operational force is inertial force, so it is generated only at the beginning of the movement. Thus proposal has advantages in terms of operability. The validity of the proposal was confirmed by simulation of contact with the environment.