Research On The Design Of Composite Magnetic Suspension Spherical Active Joint And Its Detection System

With the development of modern industrial technology,magnetic levitation technology and multi-degree of freedom motion organizations have received more and more attention.The compound magnetic suspension spherical active joint is a new type of special motor,which can realize multi-degree of freedom rotation in any direction under the condition of single joint structure,avoiding mechanical friction and wear and no lubrication,and has broad application prospects.The accuracy of pose detection of the spherical joint rotor directly determines the control accuracy of the system,and is also an important link that restricts the development of spherical motors.According to the structure and motion characteristics of the composite magnetic suspension spherical active joint,a non-contact detection technology based on optical measurement is proposed.An annular light source and a silicon photocell array are arranged on the spherical rotor and the stator respectively,and the deflection of the annular light source by the rotor causes a change in the spot area on the silicon photovoltaic array,thereby affecting the output current.A mathematical model of the short-circuit current and the spherical rotor pose angle is established.The spherical pose angle is detected by detecting the change of the output current of the annular silicon photocell array caused by the rotor attitude change.The research content of this paper is as follows:(1)The overall structure of the composite magnetic suspension spherical joint is introduced.The suspension deflection drive structure and the spindle structure of the spherical joint motor are described in detail.The principle of rotation and suspension of the spherical joint motor is proposed and used as a link,a mathematical model of the corresponding electromagnetic torque,electromagnetic levitation force,and electromagnetic pulling force;(2)The optical measuring device of the magnetic suspension spherical joint is designed,and the principle of optical measuring component is expounded.Based on this,the spherical rotor attitude and angle detection algorithm is established.The aim is to calculate the position of the spherical rotor by detecting the short-circuit current information of the silicon photocell.Posture information;(3)Selecting the silicon photocell,and based on the DSP development platform and MATLAB program,the hardware design and software design of the magnetic suspension spherical active joint rotor position detection system;(4)Constructing a magnetic suspension platform spherical active joint rotor attitude detection experimental platform,designing and processing a composite magnetic suspension spherical active joint posture detection system prototype.The experiment of position and attitude detection is carried out and the error analysis is carried out.The experiment shows that the error of attitude angle measured by the position and attitude detection system can be controlled within 0.45 degrees,which can meet the accuracy requirement of spherical motor position and attitude detection.