Ultrasonic sensors overcome many of the weaknesses of IR sensors – they provide distance measurement regardless of color and lighting of obstacles. They also provide lower minimum distances and wider angles of detection to gaurantee that obstacles are not missed by a narrow sensor beam. Measurement Procedure & Formula: Distance measurements can be made with microcontrollers in a straightforward manner: Send a 10 uS wide pulse to the sensor on the Trigger Pin. The sensor will automatically send out a 40 kHz wave. Begin monitoring the output from the Echo Pin and When the Echo Pin goes high, begin a timer. When the Echo Pin goes low, record the elapsed time from the timer and use the following conversion formula: Distance (in cm) = (elapsed time * sound velocity (340 m/s)) / 100 / 2 Note: we divide distance by 2 because the sensor returns the round trip time, which doubles the distance measurement. Refer to the timing diagram Package List: 1 x Sonar Distance Sensor
