Description
This ultrasonic module uses a separate transmitter and receiver and has all the accompanying hardware necessary to send and receive ultrasonic pulses. These sensors are able to measure distance by using high frequency, inaudible ultrasonic waves. When triggered, the module sends out a few of these waves and receives the same waves reflected back from the target (If there is one within range). The distance between the module and the target can then be calculated from the transmission and reception time of the waves. The module outputs a high pulse on the “Echo” pin with a pulse width equal to the time that it took the ultrasonic waves to travel to the target and then back to the sensor. All that is left for you to do is measure the time of the output pulse, do a simple calculation, and voila you have a distance reading.
Although this module and the HC-SR04 are very similar, people who have used the HY-SRF05 modules have reported that the they are more reliable and are able to detect objects at a higher maximum range (As far as 600cm). We still need to confirm these facts through our own testing, so these are not definite specs as yet.
Specifications:
- Model: HY-SRF05
- Operating Frequency: 40kHz
- Sensing Angle: 15° Maximum
- Detection Range: 2 – 450cm
- Resolution: 2mm
- Quiescent Current: < 2mA
- Average Operating Current: 15mA
- Operating Voltage: 4.0 – 5.0VDC
- Output Type: Digital (High level is the same as the supply voltage)
Pins Details
5-Pin, One each for VCC, Trigger, Echo, Out and Ground.
Trig : Plusing a HIGH on this pin will send a Pulse
Echo : The pulse length is propotional to the distance from the obstacle
( 100usec to 25ms, times out if 30ms)
Resources
Measurement Procedure and Formula
Distance measurements can be made with microcontrollers in a straightforward manner:
You can find an Arduino Library with code here: http://forum.arduino.cc/index.php?topic=106043.0
- 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 / 2Note: we divide distance by 2 because the sensor returns the round trip time, which doubles the distance measurement.
Packing List:
1 x HY-SRF05 Ultrasonic Ranging Sensor
