Ultrasonic Sensor Module HCSR04

This Ultrasonic sensor module has four pins i.e., Vcc, Trigger, Echo and Ground. At Vcc pin, 5 V DC is supplied to power up the sensor. Trigger pin is kept high for 10ms to start measurement by sending Ultrasonic waves. Echo pin is high for the period of time taken by the Ultrasonic wave to reach back to the sensor. The ground pin is connected to the Ground of the system. Trigger pin is an input pin while Echo is an output pin. This module simply measures the time taken by the Ultrasonic wave to strike the nearest object and reach back to the sensor. As the propagation speed of the Ultrasonic wave (330 m/s in room condition) and time taken by the wave is known, distance travelled by the Ultrasonic wave can be simply calculated by the microprocessor using the formula Distance= Speed X Time. Ultrasonic Sensor Module HCSR04 can be used in various projects for detecting nearby objects and calculating their distance.