Magnetic field analysis of a PM spherical actuator

This paper presents a three-DOF permanent spherical actuator, with precise measurement system. As magnetic model is very useful to torque model and control model, magnetic model is the basis of spherical actuator study. A new analytical magnetic field model is presented for the proposed 3-DOF spherical actuator in this paper. This analytical magnetic field method combines the Laplace equation with the equivalent magnetic charge law, which is simple and accurate. Finally, we apply the finite-element magnet analysis method to verify the accuracy of the proposed analytical method.