Design of micro-scanning actuators with large-stroke and high-bandwidth for super-resolution imaging

Super-resolution imaging technology is essential for precision optoelectronic equipment, including reconnaissance satellites, guidance seekers and airborne optoelectronic pods to enhance image resolution. The micro-scanning actuator achieves sub-pixel level scanning through precise fixed-point micro-motion, rapidly and accurately collecting multiple low-resolution image frames, which are then synthesized into higher-resolution images. Given the harsh operating environments and extremely limited installation space, these actuators must deliver large strokes in compact spaces while maintaining high bandwidth. In this paper, an actuator design method based on piezoelectric ceramic drive and rhomboid stroke amplifying and softening mechanism is proposed for planar 2-DOF micro-scanning actuator with large stroke and high bandwidth. First, the basic configuration of the actuator is proposed, and then the static and dynamic analytical models of the micro-scanning actuator are established by using the analysis method based on Castigliano’s second theorem. Then the optimization algorithm is used to obtain the optimal design parameters. A planar 2-DOF micro-scanning actuator is designed, which can achieve ±110um travel of X and Y axes and a first-order natural frequency of 430Hz. The accuracy and reliability of the proposed design method are verified by finite element simulation.