Ultrasonic Distance Sensor

An ultrasonic distance sensor is a non-contact sensing device that measures the distance between two points using high-frequency sound waves. These sensors typically generate ultrasonic signals through piezoelectric transducers operating in air and make measurements based on the time it takes for the signals to reflect off an obstacle and return to the sensor. This method is known as the Time of Flight (TOF) technique.

Working Principle

An ultrasonic sensor measures the duration of the echo produced when the emitted sound wave strikes an object and reflects back. This time interval is converted into distance using the speed of sound in air. The distance calculation is based on the following formula:

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