Permanent-magnet-spherical-motor position detection method based on 3-D magnetic-field sensors

Abstract

The invention relates to a permanent-magnet-spherical-motor position detection method based on 3-D magnetic-field sensors. A motor in which the method is suitable for use is a permanent-magnet spherical-motor, which includes a base, a spherical stator, stator coils and a spherical rotor. The rotor is located in a stator wall, and a rotor output shaft thereof extends out of an opening place on thestator wall. The motor is characterized in that the stator coils are cylindrical coreless structures, and three layers thereof are evenly distributed along an equator inside the spherical stator and on coils which are parallel to the equator, and are radially fixed on the spherical stator wall; and permanent-magnet poles are embedded in a surface of the rotor, the poles are divided into an upper layer and a lower layer along the equator, and N poles and S poles of each layer are alternately distributed. The position detection method includes: firstly, obtaining nonlinear relationships betweenmagnetic induction intensity and rotor position information according to a magnetic-field model and rotation transformation theory; integrating all the magnetic-field sensors to determine a fitness function of position calculation; and utilizing a position calculation algorithm, which combines a particle swarm algorithm and a gradient projection method, to carry out position resolution to obtain position information of the rotor.

Description

technical field [0001] The invention belongs to the technical field of position detection of a permanent magnet spherical motor, and relates to a position detection method of a permanent magnet spherical motor based on a 3-D magnetic field sensor. Background technique [0002] Multi-degree-of-freedom manipulators are widely used. In modern aerospace, military, industrial automation, intelligent robots and other fields, it is required that the end effector of multi-degree-of-freedom manipulators can be adjusted quickly, smoothly and accurately. To complete the multi-degree-of-freedom movement of the current device, it needs the mutual cooperation of multiple single-degree-of-freedom driving elements and complex mechanical transmissions. In this way, not only will the system be complicated, but also the loss of the system will be increased and the dynamic performance of the system will be reduced. These factors have promoted the development of spherical motors that can indepe...

AI Technical Summary

Problems solved by technology

Among the non-contact position detection methods, there are mainly position detection methods based on vision, optical sensors, and laser interferometers. However, the first two detection methods have high requirements for the working environment and are susceptible to external interference. The cost of position detection based on laser interferometers The magnetic field detection method has the advantages of strong anti-interference ability, unaffected by the working environment, high sensitivity, and small package, so it is favored by researchers. However, due to the complexity of the structure of the spherical motor, in order to simplify the calculation of the magnetic field model, it is often ignored. In addition, the complexity of the relationship between the output of the magnetic field sensor and the relationship between the rotor position hinders the widespread use of the magnetic field sensor

Images