Improved Multi-Motor Synchronization Control of Underwater Robot Based on Virtual Shaft

Underwater robot is the main equipment used to develop underwater resources. This paper solves the problem of speed and load imbalance of multi-motor when the underwater robot works in the random interference environment. A multi-motor synchronization control strategy based on the virtual shaft is proposed. A normalized proportional coefficient distribution method is constructed to achieve all the different speed motor cooperation. Furthermore, it solves the problems of low control accuracy, and slow dynamic response caused by multi-motor cooperation. A backstepping sliding mode controller with dynamic surface is constructed. Combining backstepping control and sliding mode control to eliminate the underwater random nonlinear disturbance. The simulation results demonstrate the multi-motor propulsion under the control of this scheme has good rapidity and robustness when dealing with random disturbance and large instantaneous load disturbance.