Enhanced Predefined-Time Tracking and Synchronization Control for Multimotor Servo Systems

An enhanced predefined-time control strategy is proposed to achieve load tracking and motor synchronization for multimotor servo systems. A new sufficient condition of the Lyapunov function is established to guarantee both predefined-time stability and practical predefined-time stability, which results in a smaller convergence domain. Based on this condition, we develop a predefined-time sliding mode tracking controller that ensures the convergence of the tracking error between the load output and the desired trajectory. This controller exhibits predefined-time convergence capabilities in both the reaching and sliding mode phases. To solve the synchronization problem between motors, a novel predefined-time synchronization controller is proposed within the mean relative coupling control framework, ensuring rapid consistency of motor speeds. The convergence time for both the tracking error and the synchronization error is predefined based on practical requirements. The stability of the proposed control method is guaranteed by Lyapunov theory. Furthermore, numerical simulations and experiments are conducted, and performance indicators are used to quantitatively analyze the results, thereby demonstrating the effectiveness of the proposed method.