HC-SR04 Ultrasonic Module
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.
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
- Easy to assemble
- Compatible with Raspberry Pi and Arduino and so on.
- Working Voltage DC 5 V
- Working Current 15mA
- Working Frequency 40Hz
- Max Range 4m
- Min Range 2cm
- MeasuringAngle 15 degree
- Trigger Input Signal 10uS TTL pulse
- Echo Output Signal Input TTL lever signal and the range in proportion
- Dimension 45*20*15mm
- 5V Supply
- Trigger Pulse Input
- Echo Pulse Output
- 0V Ground
The Timing diagram is shown below. You only need to supply a short 10uS pulse to the trigger input to start the ranging, and then the module will send out an 8 cycle burst of ultrasound at 40 kHz and raise its echo.
The Echo is a distance object that is pulse width and the range in proportion .
You can calculate the range through the time interval between sending trigger signal and receiving echo signal.
Formula: uS / 58 = centimeters or uS / 148 =inch; or: the range = high level time * velocity (340M/S) / 2
we suggest to use over 60ms measurement cycle, in order to prevent trigger signal to the echo signal.
- 5 x Ultrasonic sensor
How to use
- Distance Sensing With Raspberry Pi and HC-SR04: [[ https://www.instructables.com/id/Distance-Sensing-With-Raspberry-Pi-and-HC-SR04/ ]]
- Raspberry- Pi (On-board computer) based Intelligent:[[ https://pdfs.semanticscholar.org/a3f3/287527e47c29ba1cdf3efadd5ce4b0eb2811.pdf ]]
- holiday-special--santa-trap: [[ https://www.element14.com/community/community/raspberry-pi/raspberry-pi-bplus/blog/2014/11/06/holiday-special--santa-trap ]]
- Ultrasonic sensor, distance sensor, Raspberry Pi 4B, arduino