Ironless voice coil actuator used for active magnetic gravity compensator

In this paper, we analyse a moving-magnet type ironless voice coil actuator that can be used as active gravity compensator. Gauss numerical integral is employed to solve the force-position relationship. Based on it, the travel region of the moving magnet in which the voice coil actuator has the spring effect has been determined. What's more, with the force-position relationship, we acquire the dynamic model of the system and construct the nonlinear compensator in the control unit. An experiment prototype is developed to highlight the performance of proposed voice coil actuator. The character of spring effect and the results including step response, trajectory tracking and load regulation are presented.