A Study of Advanced Spherical Motor for Improvement of Multi-DOF Motion

Abstract

-Since robot industry growing, the machine that could move with multi-DOF has been studied in many industrial fields. Spherical motor is one of the multi-DOF machine that doesn't need gear for multi-DOF motion. Unlike conventional motor, spherical motor can not only rotate on the shaft axis (rotating motion), but tilt the shaft with 2-DOF motion (positioning motion). In the typical type of spherical motor, one coil took part in positioning motion and rotating motion at the same time. As the result, the control algorithm was complex. To solve this problem, this study proposed a novel type of coil on the stator. The coils were separated for positioning motion and rotating motion. Thus the linkage flux of rotating coil didn't be affected the positioning angle. In this paper, comparing the back-EMF of typical and novel type was conducted and the driving experiment was carried out as the positioning angle. From the experiment result, the performance of proposed spherical motor could be verified.

Dynamic Analysis of Double Excited 3-DOF Motor Modeling Using Equivalent Magnetic Circuit

“…Multiple degree of freedom motors have been a topic of interest due to their wide application in industry, such as for helicopters, boat propellers, robots, and so on [1][2][3][4][5]. The 3-DOF machine studied in this paper does not contain any permanent magnets and only field excitation is used, which reduces both the size and cost of the machine [6][7].…”

3D Magnetic Analysis of Permanent Magnets in Spherical Configuration

“…Hyun-Jong Park and et al introduced a several studies about performance increasing of permanent magnet spherical motor. [27][28][29]. Bin Li and et al implemented a spherical motor design by using spherical harmonics [30].…”