Designing a real time embedded controller using data acquisition system for a DC motor speed control

Abstract

Speed of a DC motor varies proportional to the input voltage. With a fixed supply voltage the speed of the motor can be changed by switching the supply on and off so frequently that the motor notices only the average voltage effect and not the switching operation. This thesis focuses on controlling the speed of a DC motor using PWM technique (varying duty cycle of a square wave) and Data Acquisition Systems.
Virtual instrumentation is defined as the combination of measurement and control hardware and application software with industry-standard computer technology to create user-defined instrumentation systems. DAQ card along with LabVIEW are used to create the virtual instrument for designing a real time embedded controller for controlling the speed of a DC motor in an open loop control system. The DAQ card used is NI PCI 6221 along with daughter board CB-68LP. A ZX-03 IR reflector type sensor is used to study the speed of the motor.