Development of a novel maglev positioner with self-stabilizing property

This paper presents a novel six degrees of freedom (d.o.f) maglev positioner devoid of mechanical friction which is one of the most severe factors that limit the resolution of a system. One moving part levitated magnetically over fixed element is an inherently unstable, namely open-loop unstable. And the magnetic force acting on the levitated part is nonlinear in nature. Then the system requires a considerably computational load in the control aspect to compensate the instability and nonlinearity of rigid body in space, and to achieve the satisfactory performance. Therefore, we have focused on realizing self-stability with a minimum feedback signal and optimized principal parameters to obtain high disturbance rejection property of the uncontrolled d.o.f with only the passive stability. It means that we can care for a performance of the controlled d.o.f without considering the stability of the uncontrolled d.o.f. We demonstrate that it is possible for the system to achieve the desired performance with feedback of just a position signal via the experiments.