Flyball Tachometer

This fly-ball tachometer demonstrates how rotational velocity can be measured using an ultrasonic sensor and a rising platform mechanism. The system includes an AC–DC converter, a DC motor with a Hall-effect encoder, a motor controller, an LCD for displaying RPM, a potentiometer for speed adjustment, an Arduino UNO R3 for interfacing, and an ultrasonic sensor for height measuring. We generated a curve fit by collecting data points relating platform height to encoder-measured RPM, and then used that relationship to estimate shaft angular speed directly from the ultrasonic sensor readings.