Design and test of an ironless, three degree-of-freedom, magnetically levitated linear actuator with moving magnets

This paper concerns the design and test of a ironless three degree-of-freedom linear actuator. The motor consists of stationary coils and a translator with permanent magnets. The translator is magnetically levitated (z-direction) and provides long-stroke motion along the x-axis and limited rotation about the y-axis. The three degree-of-freedom motor is a preliminary study for a six degree-of-freedom planar motor. The actuator is designed using a tool, which is based on the analytical magnetic field solution of a permanent magnet and numerical integration over the coil volumes. Both force and EMF measurements and finite element analysis show the accuracy of the design tool