Control of Miniature Linear Actuator Using Sensorless Measurement of Position of a DC Driving Micromotor

The presented research was aimed at creating and testing a control system of a spooler for winding miniature induction coils. The discussed analysis was realized in order to verify a possibility of synchronizing the speed of the spindle drive (stepping motor) with the speed of the wire feed unit (miniature linear actuator based on a DC micromotor). A method of a sensorless measurement of rotor displacement of a DC micromotor was applied to control position of the actuator. The method is based on analysis of the current signal and its pulsation corresponding to the shaft rotation. An ATmega8 microcontroller communicating with PC was used to implement various control algorithms. Using a prototype of the controller, there were performed tests of the drive system, proving that synchronization between drives of a different type by means of the proposed method of analyzing current signal in a DC micromotor is possible