Reddit reviews ELEGOO 5PCS HC-SR04 Ultrasonic Module Distance Sensor for Arduino UNO MEGA2560 Nano Robot XBee ZigBee
We found 4 Reddit comments about ELEGOO 5PCS HC-SR04 Ultrasonic Module Distance Sensor for Arduino UNO MEGA2560 Nano Robot XBee ZigBee. Here are the top ones, ranked by their Reddit score.
Ultrasonic hc-sr04 distance measuring transducer sensorHC-SR04 consists of ultrasonic transmitter, receiver, and control circuit. When trigged it sends out a series of 40KHz ultrasonic pulses and receives echo from an object.~Power supply: 5V DC; quiescent current: less than 2mA; effectual angle: less than 15°; distance: 2cm500cm; resolution: 0. 3 cm~Package Content: 5pcs HC-SR04 with a little gift
Not quite. The board I have (which is fairly common) has two pins for trigger/echo. I've wired them together. So I write HIGH out then LOW then read it back. I presume writing to the ECHO pin does nothing.
Indeed on my board it works just fine. I can read distances and actually compare them to a ruler to get somewhat precise results. I mean even with two wires it's hardly a super precise mechanism anyways.
edit: To add... the boards I'm talking about are things like this. It has a speaker and a mic with a little control circuit to trigger the echo pin only if the signal is received. The trigger comes in one pin and the echo leaves another. In my "1 wire" setup they're simply wired together. So I'm setting the "echo" pin high but that doesn't appear to do anything negative.
https://www.amazon.com/Elegoo-HC-SR04-Ultrasonic-Distance-MEGA2560/dp/B01COSN7O6/ref=pd_sim_147_4?_encoding=UTF8&psc=1&refRID=TPBMW2PJ392W4FE64FX1
these should work too, if you find a way to make them more resistible.
Certain sensors, like the HC-SR04 distance sensor, require very reliable, low-latency real-time processing in order to measure the echo time. Raspbian isn't a real-time OS out of the box, so measuring sound wave travel time isn't very practical without some hackery.
I personally have a distance sensor pointed at my sump tank to measure water level, and I have that hooked up to an Arduino that buffers data from sensors, and in turn I have that hooked up to a Raspberry Pi.
Also, as /u/icarus901 mentioned about sensors being consumables, definitely buy sensors in bulk.
As for the controllers themselves, I have them in Ziploc bags because I'm cheap :P
This is for the Arduino starter kit.
This is just the distance sensor.