Speed and Position Control of Stepper Motor using 8051 Microcontroller

Speed control of machine is the most vital and important part in any industrial organization. This research work focuses on speed and position control of stepper motor using 8051 microcontroller. The speed of stepper motor has been controlled by the delay between consecutive pulses of stepper motor phases provided by microcontroller. Actually speed is inversely proportional to delay between pulses of consecutive phases and Position of stepper motor has been controlled by the number of revolutions. In this project work step angle of 15 degree per step has been taken when motor is moving in clockwise direction and 7.5 degree per step when moving in anticlockwise direction. The direction of movement of stepper motor depends on opening and closing of switch. When switch is closed, motor moves in clockwise direction and when switch is opened, motor moves in anticlockwise direction. Furthermore, variable resistor connected to pin no. 6 of ADC has been varied in clockwise direction due to which speed increases and when varied in anticlockwise direction speed decreases. In this project work infrared sensor has been used to detect speed of stepper motor in rpm. Speed in rpm & step angle in degree has been displayed on LCD screen and output pulses can be observed on CRO. The control program has been written in assembly language and Kiel compiler has been used to convert this control program into executable file or in a HEX code. This hex code has been burnt into microcontroller by Flash Magic software.