Development of An Optimal Low-Noise Voice-Coil Actuator for Precision Motion Control Applications

Voice-Coil Actuators (VCAs) serve as indispensable components in precision motion applications, valued for their linear force performance, smooth operation, and compact size. The optimal design of VCAs not only contributes to cost reduction in manufacturing and assembly but also results in a more compact size and increased bandwidth, enhancing VCA’s overall performance. On the other hand, developing a model that captures the nonlinear features of actuator dynamics is essential for advancing high-performance controllers. In addition, such a model can be very useful in simulating the performance of controllers before implementation, as well as studying the behavior of different parts of the actuator during its operation. This paper introduces a novel approach to VCA design through a multi-objective optimization problem solved using the Non-Dominated Sorting Genetic Algorithm-II (NSGA-II). Once the optimal design is determined, it undergoes validation via finite-element analysis. After validating the optimal design, the actuator is fabricated and assembled through a detailed electromechanical design. To mitigate potential noise issues arising from switching circuits, the study proposes a high-bandwidth analog servo amplifier. This amplifier is designed to effectively mitigate noise problems, ensuring the seamless operation of the VCA in practical applications. Before modeling, the characterization process is undertaken through a combination of simulation and experimental tests. Finally, the effectiveness of the multi-physics-based modeling approach, enhanced by experimentally-driven characteristics, is evaluated against empirical results.