Affiliations: [a] School of Electrical Engineering , Hebei University of
Science and Technology, Shijiazhuang, Hebei, China
Correspondence:
[*]
Corresponding author: Zheng Li, School of Electrical
Engineering, Hebei University of Science and Technology, Shijiazhuang 050018,
Hebei, China. Tel.: +86 311 86924334; E-mail: Lzhfgd@163.com
Abstract: Modeling and torque characteristics analysis are important for
actuators or motors with complicated structures. Based on the presented
configuration design, the magnetic field and torque calculation for a multiple
degrees-of-freedom (M-DOF) spherical actuator are performed using 3D FEM. To
reduce the computation workload, a simplified torque calculation model and
non-linear system dynamic model have been proposed, and magnetic levitation
mechanism is developed for alleviating the friction and resistance to improve
the dynamic performance of this M-DOF actuator. A linear mathematical model of
the levitation force is deduced and corresponding control scheme with power
drive unit is discussed. Then the diagonal recurrent neural network (DRNN)
based control scheme is presented to improve the performance of levitation by
adjusting parameters online as identifiers. Simulation and experiment results
show that the actuator can effectively implement 3-DOF motion combined with
levitation mode, and that the proposed approach can be applied to M-DOF
actuators of the same kind effectively.
Keywords: Magnetic levitation, M-DOF actuator, modeling, neural network control
