Contouring Error-Bounded Control for Biaxial Switched Linear Systems

Biaxial motion control systems are widely employed in manufacturing industries, where improving throughput and reducing machine costs are critical goals. To achieve these, lightweight materials are increasingly being used in structural components, though this often introduces higher flexibility in the machine links, leading to position-dependent precision loss in the end-effector. This article addresses the challenge of maintaining contouring accuracy in such systems by proposing a novel contouring error-bounded control algorithm for biaxial switched linear systems. The algorithm employs model predictive control (MPC) to enforce state, input, and contouring error constraints across different system modes, even when mode switching is not known in advance. While the exact switching signal is unknown, the controller assumes knowledge of the minimum dwell time the system remains in each mode. The proposed algorithm guarantees recursive feasibility and ensures closed-loop system stability. The effectiveness of the method is validated through a high-fidelity simulation of a dual-drive industrial laser machine, demonstrating that the contouring error is consistently maintained within the specified tolerance.