Improvement of operationality under time varying delay for bilateral teleoperation systems by differential signal based data modulation

This paper proposes a method to improve the operationality of bilateral teleoperation systems under time varying delay. Operationality is an index of the smoothness of an operation and is a performance index of bilateral teleoperation systems. Deterioration of operationality is salient under time varying delay communication because it causes system vibration. Therefore, this paper presentsa novelmethod to improve the operationality in bilateral teleoperation systems by introducing differential signal based data modulation. The data modulation method transmits the original signal and its derivative via the network to mostly eliminate the effect of varying components in the time delay on the received information. Compared with conventional methods, the proposed method improves the operationality of a system while maintaining its symmetric structure but not increasing the time delay. Two experiments were conducted to show the validity of the proposed method.