Distance Sensor HC-SR04: Incorrect measurement
sunnyboy69 last edited by
I experimented with several HC-SR04 using a very simple scetch with Arduino 1.8.5, reading the measurements on the serial monitor. For a static setup I fastened the HC-SR04 in a vice and had it point against a white wall, inside a dust free room. No matter which distance between the wall and the sensor adjusted, the readings kept on being more or less constant BUT all of a sudden for a few readings the values decreased to almost zero and then continued with the expected measurement.
Does anybody have an explaination for this phenomena?
Thanks for your assistance in advance.
bjacobse last edited by
I have had similar issue and to bypass this, I did 3 last measurements needed to be equal, before the result was accepted.
Off cause this requires that your moving target was not too quick, which mine wasn't
zboblamont last edited by
@sunnyboy69 Getting false readings can be anything as it depends if it is a serial read from the device or simple timing of the echo, unstable voltage, or even an object caught in the path of quite a wide cone, but without further details it is impossible to identify. I've been caught before with a serial reading device, took a while before I realised....
An extension of what @bjacobse suggested is to repeat readings until you get two identical consecutive results which are <> known limits and not cuckoo results..