Linearization design of a XY stage based on hybrid reluctance actuators

The nonlinearity of hybrid reluctance actuators (HRA) significantly restricts their applications in XY stage requiring long stroke, high bandwidth, and high precision. This paper presents an improved design methodology and experimental verification focusing on nonlinearity reduction of a XY stage based on hybrid reluctance actuators (HRA-XYS). Initially, the primary sources of nonlinearity in conventional HRA were analyzed, leading to a magnetic flux topological optimization approach for nonlinearity mitigation. Subsequently, a comprehensive dynamic model incorporating nonlinear characteristics was established, followed by a nonlinear optimization framework for key parameter design. Based on the optimization results, a prototype was fabricated for comprehensive performance evaluation and a proportional-derivative (PD)-based feedback compensator was implemented to extend bandwidth by actively modifying system stiffness and damping. Experimental results demonstrate significant improvements: nonlinearity <3.2 %, cross-axis coupling <0.4 %, positioning accuracy better than 0.1 μm, working stroke exceeding ±500 μm, and bandwidth of 375 Hz. These achievements verify the effectiveness of the proposed linearity-oriented design methodology and underscore its advance compared to similar works, indicating that the optimized actuator exhibits superior comprehensive performance in precision, stroke capability, and dynamic response characteristics.