Design And Analysis Of A Novel Permanent Magnet Hybird Driven Three-Degree-of-Freedom Motor

With the development of modern precision manufacturing industry and the continuous breakthrough in the field of human bionics,multi-degree-of-freedom motion actuators have entered our vision more and more.The traditional multi-degree-of-freedom actuator consists of multiple single-degree-of-freedom motors,which are bulky and inefficient.Multi-degree-of-freedom motor solves this problem properly,with small size,light weight and high energy index.Therefore,the application prospect of multi-degree-of-freedom motor is very broad.The traditional multi-degree-of-freedom motor is generally spherical motor with low rotation speed and small output torque.The novel permanent magnet hybrid driven three-degree-of-freedom motor proposed in this paper solves this problem.Hybrid drive technology is adopted in this motor,improves the rotation speed and the load capacity of the motor,promotes the vigorous development of the multi-degree-of-freedom motor.The specific work of this paper is as follows:1)A new type permanent magnet hybrid driven three-degree-of-freedom motor is proposed.This motor consists of two parts: the outer rotation module and the internal deflection module.The deflection module is located inside the rotor yoke of the rotation module.Space movement of the output shaft is realized through the coordinated control of the rotation motion and the deflection motion,and improves the output torque of the motor,the rotation speed and the control accuracy.2)The magnetic field shielding and optimization of the two modules inside and outside the motor are realized by applying Halbach permanent magnet array as the rotating permanent magnet and deflection permanent magnet,the magnetic collecting effect and magnetic field characteristics are improved.The analytic method and finite element method are used to analyze the magnetic field characteristics and distribution of the rotating and deflecting permanent magnets of this motor.The accuracy of the mathematics model and finite element model is verified by comparing the analytical results with the finite element method results.The electromagnetic character of load and no load condition are analyzed and calculated,proving the fine electromagnetic character of the motor.3)The output torque of the hybrid driven three-degree-of-freedom motor is analyzed and calculated,and the rotation and deflection torque characteristic curves obtained by finite element method are compared with the analytical result to verify the excellent torque characteristics of the motor.4)In order to comprehensively measure the performance of the motor,the eddy current loss,stator core loss and copper loss of the stator winding are analyzed and calculated.The finite element calculation results are compared with the results summarized by traditional motor theory experience.The conclusion is that the characteristics of motor loss are fine when the motor output power is constant.5)In order to improve the output torque,the Taguchi algorithm and the central composite design method are used to establish the numerical model equation of the response surface of the motor.Based on the goal of maximizing the output torque of the motor,the optimal structural parameters of the motor are proposed.Compare the result with finite element experiment,the accuracy of the structural parameters is verified.6)The dynamic model of the motor is established by ADAMS software.The influence of the motor running track and bearing friction on the running characteristics are analyzed and calculated.The time characteristic of linear velocity,angular velocity and centroid displacement of the rotation and deflection motions are calculated and analyzed.Providing theoretical support for the subsequent optimization and experimental design of the motor.7)The prototype of the motor is fabricated.The winding electromotive force and back EMF are measured.The accuracy of the response surface equation and ADAMS kinematics simulation results are verified by prototype experiments.