HC-SR04 ultrasonic range finder (max 4000mm)

[thunderer]

Hi all,
I built some time ago a "range finder" based on the cheap ultrasonic module HC-SR04 (max 4000mm). I wrote a small program in Mikrobasic and have the result displayed on a 8x2 LCD. A PIC 16F630 is the brain behind all.

I found some people were interested in this project, so here it is shared with you. I am available for questions, but I guess all is so simple... Source, HEX, schematic, PCB in Eagle (see attached) and some explanations on my blog (including pictures with finished project and a small video).

Feel free to customize your PCB as per your needs.

[f22kma]

What accuracy have you achieved and how did you measure it? In a confined space, were there effects from multiple signal return paths?

[thunderer]

You have to understand that we speak about a $1.5 module. I measure with a ruler (this is how I calibrated), and you have to point the signal perpendicular on the object. Any angle will give you any reading. The object has to be big enough.

[Catcatcat]

I also experimented with the modules. I have a maximum range of measurement was not more than 3 meters. Accurate to within one centimeter. Very wide angle capture. In the video, 1.74 meters is the distance from the surface of the table to the ceiling.

http://www.youtube.com/watch?v=jDSJlmL5ZSU

http://catcatcat.d-lan.dp.ua/en/skachat/primeryi-postroeniya-koda-programm-dlya-pic-kontrollerov/izmerenie-rasstoyaniya-pri-pomoshhi-ultrazvukovogo-modulya-hc-sr04/