An infrared LED pair based approach to measure high rotation velocity of a motor

To measure the high rotation velocity of a motor, this paper proposes a scheme based on an infra-red led pair and integrated chip technology. By analyzing the infrared LED pair working principle, this paper designs a framework including a signal processing algorithm to measure the rotation velocity and display it in real-time. In details, the paper describes the technical specifications about how to use a SCM (Single Chip Microcomputer) and photoelectric sensor to design the hardware circuit and software programming for this system. The hardware circuit, mainly including photoelectric sensor module, pulse signal processing and display module, uses AT89C51 microcontroller as the core chip. With a specific algorithm, the pulse signal sent into the SCM will be processed and the motor rotation velocity will be displayed on a four seven-segment digital tube. Experimental results show that the rotation velocity measurement system is stable, reliable and has a great potential for a wide range of engineering applications.