Predictive Display for Telerobot Based on Time-delay Prediction

In order to solve the predictive display problem of teleoperation system with large time-varying delay, a predictive display method based on time delay prediction is proposed. In this method, the tensile and compressive effects of the varying communication delay on the master-slave control signal in the time dimension are considered as system disturbance, and the on-line delay prediction result is used to perform feedforward compensation on this disturbance. Firstly, the dynamic model of the predictive display based teleoperation system is presented, and the expected control variable of the predictive robot with disturbance is calculated. Then, the mechanism of the communication delay of the space teleoperation system which has the most complex delay composition is analyzed, and the delay is predicted on line according to it's generation mechanism, model and statistical law. Finally, the feasibility and effectiveness of disturbance compensation by delay prediction results are analyzed theoretically, and a contrast test is conducted on the theoretical verification teleoperation system. Experimental results show that compared with predictive display method without time-delay prediction, the proposed method's relative errors of the velocity prediction and the contact force prediction decrease 30.9% and 56% at the peak of errors respectively, under large time-varying delay.