Grove – Ultrasonic Distance Sensor
The Grove – Ultrasonic Distance Sensor is an ultrasonic transducer that utilizes ultrasonic waves to measures distance. It can measure from 3cm to 350cm with the accuracy up to 2mm.
This module has an ultrasonic transmitter and an ultrasonic receiver so you can consider it as an ultrasonic transceiver. Familiar with sonar, when the 40KHz ultrasonic wave generated by the transmitter encounters the object, the sound wave will be emitted back, and the receiver can receive the reflected ultrasonic wave. It is only necessary to calculate the time from the transmission to the reception, and then multiply the speed of the sound in the air(340 m/s) to calculate the distance from the sensor to the object.