Ultrasound Distance Sensor HC-SR05

Ultrasound Distance Sensor HC-SR05 description

Ultrasonic sensors overcome many of the weaknesses of IR sensors by providing distance measurement regardless of the color and illumination of obstacles. < They also provide shorter minimum distances and wider detection angles to ensure obstacles are not lost by a narrow detection beam.
That particular model is an upgrade to the popular HC-SRO4 with better precision. It has 5 pins and can be used in 1 pin trigger / echo mode or 2 pins.

Ultrasound Distance Sensor HC-SR05 features:

- Power supply: 4.5-5.5 VDC
- Supply current: 10 to 40 mA
- Activation pin format: 10 μs digital pulse
- Echo Pin Output: 0-Vcc
- Echo Pin Format: the output is DIGITAL and directly proportional with range. See our conversion formula below
- Measurement range: 2cm to ~ 4.5m
- Measurement resolution: 0.3cm
- Measurement angle: up to 15 degrees
- Measurement speed: 40 Hz,
- Connector: standard 5-pin male connector that can be connected directly to boards or breadboards:
- 1: VCC
- 2: Trig
- 3: Echo
- 4: OUT
- 5: GND
- Size: 45Ã — 21 mm

Distance measurements can be done with microcontrollers in a simple way:
You can find an Arduino library with the code in the arduino forum.
Send a 10 μs wide pulse to the sensor on the trigger pin (Trigger). The sensor will automatically send a 40 kHz wave.
Start monitoring the output of the Pin Echo and:

- When the Pin Echo goes high, start 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 * speed of sound (340 m / s)) / 100 / 2
Note: We divide the distance by 2 because the sensor returns the round trip time, which doubles the distance measurement.