Integrated sensor based hybrid stepping motor fuzzy speed servo system

Hybrid stepping motors, promising as a high torque and low-speed servomotors, are widely used in microcomputer-controlled machines where they have to perform high-precision positioning operations. But the variations of the mechanical configuration of the drive can lead to step losses. Moreover, the open-loop speed control is weak and a closed loop control is required. The major obstacle to the successful implementation of a closed-loop controlled stepping motor servo system is the cost of a high-resolution optical encoder. In this paper we propose an integrated sensor to get the rotor information, and applying fuzzy control theory to control the speed of a stepping motor. The experiment has been performed using a TMS320F240 DSP. The very good accuracy of the proposed control algorithm is confirmed by experimental results.