Research On Trajectory Tracking Control System Of Permanent Magnet Spherical Actuator Based On Active Disturbance Rejection Control Technology

Permanent magnet spherical actuator(PMSA)has the advantages of simple structure,small volume,high positioning accuracy,fast response speed and good dynamic and static performance,which is applied in high-end equipment fields such as multi-dimensional precision machining,radar tracking system,human prosthesis and so on.However,permanent magnet spherical actuator is a typical multivariable,coupled,time-varying nonlinear system.Therefore,in the process of structure design,magnetic field analysis,dynamics analysis and motion control of permanent magnet synchronous actuator,more factors should be considered than traditional actuator.Therefore,in this paper,active disturbance rejection control(ADRC)technology is used to study the motion control system of a three degree of freedom permanent magnet spherical motor.The main contents of this paper are as follows:1.The basic structure of permanent magnet spherical actuator is introduced.The dynamic control model of the spherical motor is established by rotating coordinate transformation and Lagrange equation.2.In this paper,a kind of communication system of permanent magnet spherical motor based on Lab VIEW is designed,and the real-time attitude detection based on optical sensor is realized.Through three ADNS-9800 optical sensors installed on the stator shell are used to detect the speed information on the rotor surface in real time.The speed information is transmitted to the upper computer by the microcontroller STM32f4,and then the real-time angle information of the rotor body is obtained by integral operation.Finally,the real-time position information of any point on the rotor body is obtained by coordinate transformation and the initial attitude information of the point.The experimental results verify the effectiveness of the detection method.3.An active disturbance rejection control scheme based on single parameter nonlinear extended state observer is proposed.By designing a tracking differentiator,the influence of expected trajectory jump is reduced.At the same time,a single parameter nonlinear extended state observer is designed to observe and calculate the system coupling,external disturbance and model error on line.Finally,the nonlinear control law is used to compensate the observed disturbance,and the stability is proved based on Lyapunov equation.The simulation results verify the feasibility of the control scheme.4.The experimental platform of permanent magnet spherical motor trajectory tracking control system based on active disturbance rejection technology is built.The experimental results show that the system still has good static and dynamic performance in the face of model error and random disturbance,which verifies the effectiveness and accuracy of the proposed control scheme.