Introduction, Simulation and Experimental Investigation of a Planar Positioner Based on Permanent Magnet Linear Synchronous Motor Technology

The aim of this research is to design and fabricate an actuator, which operates based on reaction forces between current carrying stator coils and magnetic arrays (Halbach arrays) connected to the mover, in order to move a motion stage for positioning objects. Thus, according to the initial and intended position of the mover, current commutation in stator coils is changed in a way that required force for transporting the mover to the desired position is provided. In this research, the integration of two perpendicular synchronous linear motors is utilized in order to create the planar motion. The stator consists of two sets of rectangular coils, which are placed perpendicular to each other. Mover consists of four Halbach arrays, which two Halbach arrays are used for x-axis motion and the other two arrays are used for y-axis motion. First, the analytic relationship between the applied magnetic force and current commutation was introduced. Then, the design parameters such as mover dimensions and stator workspace were determined. Concerning these parameters, dimensions of cubic magnets for Halbach array fabrication were obtained and with respect to array dimensions, the dimensions and number of turns for stator coils were determined. Using these design parameters and commutation equations, the planar motion of the actuator was simulated. The simulation results showed good agreement with the analytical results. Experimental tests were conducted in order to investigate the positioning capabilities and 2 dimensional motion. The precision of the fabricated actuator is 5mm and the minimum response time of actuator is 0.5sec. The minimum position error occurs at 25mm position that is due to the closeness to motor magnetic period.