The HC-SR04 Ultrasonic Distance Sensor can measure distances between 2cm and 400cm (4 meters), with up to 3mm accuracy. This cheap but accurate sensor lets you build range-sensing projects with ease.
Each sensor “package” already has a transceiver and controller built-in. You only need to worry about 4 pins all-in-all. VCC (Power), Trig (Trigger/Transmit), Echo (Receive), and GND (Ground).
HC-SR04 Distance Sensor Specifications:
- Operating Voltage: 5v
- You can use this for 3.3v projects (Raspberry Pi). Simply use a 1k or more resistor on Echo pin. Adjust resistance as necessary, or use a variable resistor.
- Operating Current: 15mA
- Measure Angle: 15°
- Ranging Distance: 2cm – 400cm(4m)