Optimal Design and Control of a Planar Voice-Coil Actuator for Micropositioning Applications

Voice-coil actuators (VCAs) are widely used in precision motion applications due to their linear force behavior and smooth operation. VCAs can be found in different shapes and geometries, such as planar and cylindrical. One of the most meritorious benefits of the planar rectangular VCAs is their planar compact form leading to occupying less space with almost the same operation, that is beneficial in the systems where the space is limited. In this paper, the electromagnetic analysis and optimal design of a planar VCA and its characterization and modeling are discussed. The main application of this actuator is precision positioning and in order to outreach that, a digital controller is designed. The main problem that the controller and system encounter is friction since no return spring is used in the actuator to minimize the effect of friction. In order to address this problem, a friction compensator is designed and implemented to rectify the control effort and reduce the steady-state error. Finally, the system has been examined with and without a friction compensator, and the results have been reported for comparison.