Research On Trajectory Planning Of Permanent Magnet Spherical Motor

With the development of modern industry and science technology,people have more and more demands for motion devices that can achieve multi degrees of freedom.Due to the permanent magnetic spherical motor(PMSM)has significantly simplified the complexity of the system,so it has gradually become a research hotspot.The energy consumption,running time and smoothness of the PMSM are important performance indexes,which directly affect the dynamic performance of the control system.Therefore,it is necessary to conduct corresponding research on its trajectory planning and optimization.In this paper,aiming at the trajectoxy problem for a PMSM under specific path in three-dimensional space,a time-optimal trajectory planning strategy based on genetic algorithm(GA)and a multi-objective trajectory planning strategy with optimal time and energy consumption is proposed,respectively Specific research works of this paper are as follows:1.Firstly,the basic structure of the permanent magnet spherical motor is introduced.The three-dimensional model of the permanent magnet spherical motor rotor is drawn by Pro/Engineer software and imported into ADAMS to complete the virtual prototype modeling.At the same time,the dynamic mathematics model of the PMSM is established by combining the Lagrange equation of multi rigid body mechanics.2.Secondly,combined with the given path points,the B spline interpolation method is used to construct the continuous trajectory in joint space.At the same time,the GA is used to design a time-optimized scheme of a permanent magnet spherical motor under the dynamic and kinematic constraints by taking the shortest time as optimization objective.Then the simulation analysis is carried out.3.Finally,the Non-Uniform Rational B-Spline is adopted to construct the trajectory curve of a permanent magnet spherical motor.At the same time,taking the optimal time and the energy optimal as the optimization objectives and the fast-non-dominated sorting genetic algorithm(NSGA-II)is used to optimize the trajectory,and the optimal solution is selected according to the Pareto solution set.Then the simulation analysis is carried outThe work of this paper was supported by Key projects of National Natural Science Foundation of China(51637001),National Natural Science Foundation of China(51307001),Key project of Natural Science in Anhui Provincial Department of education(KJ2017A001).