Decoupled bilateral control based on modal space observer in master-slave systems with different masses

This paper proposes a decoupled bilateral control based on a modal space observer. In a conventional bilateral control system, the structures of master-slave systems are not considered. This paper shows that a force controller and a position controller in a bilateral control system are interfered when the structures of the master-slave systems are different. In order to solve this problem, a bilateral control system based on a hybrid matrix has been proposed previously. However, the computational process for calculating the hybrid matrix becomes complicated when the number of DOF of master-slave systems is increased. In the proposed method, a nominal equivalent mass matrix with respect to the modal space is used, and the interfered terms are estimated and compensated for using a modal space observer. Therefore, a simple control structure is realized using the proposed method. The performance of the proposed method is compared with that of the conventional methods by simulations and experiments, and the validity of the proposed method is verified.