Ultrasonic distance meter HC-SR05.

With the ultrasonic distance sensor HY-SRF05, you can easily perform length measurements with the Arduino. You can also build a robot that detects obstacles with the HC-SR05 and can avoid them. The sensor is very easy to control. Thus, it is suitable for beginners. The HC-SR05 is almost identical to its predecessor HCSR04, except for the following differences:

Improved resolution: New 2mm
Additional OUT pin available

Operating mode 1 SRF04 Compatible Mode:

The control can be done as before: With the pins VCC, trig(T), echo(R), and GND. If the trig(T) pin is set to high for 10u, the sensor performs a measurement. If an object is detected in the measuring range, the Echo pin is set high proportional to the measured distance. The distance can then be easily calculated:

Distance = ((Echo signal duration) * (speed of sound: 344m/s)) / 2

There is a second operating mode where the sensor can be controlled with only one control line. We will introduce this mode later in our blog.