Ultrasonic Ranging Module HC-SR04
The HC-SR04 ultrasonic sensor uses sonar to determine distance to an object - just like bats or dolphins do.
This module offers excellent range accuracy and stable readings in an easy-to-use package. It operation is not affected by sunlight or black material (although acoustically soft materials like cloth can be difficult to detect). Similar in performance to the SRF005 but with the low-price of a Sharp infrared sensor.
Perfect for collision avoidance on your next robotics or multirotor project!
Ultrasonic Ranging Module HC-SR04 provides 2cm - 400cm non-contact measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit.
The basic principle of work:
- Using IO trigger for at least 10us high level signal,
- The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back.
- If the signal back, through high level , time of high output IO duration is the time from sending ultrasonic to returning.
- Test distance = (high level time×velocity of sound (340M/S) / 2