Sonar codebug - ultrasonic ranger

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mikerr
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Joined: Fri Jul 31, 2015 10:37 am
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Sonar codebug - ultrasonic ranger

Post by mikerr » Fri Oct 30, 2015 9:01 pm

Use a HC-SR04 ultrasonic sensor with the codebug to detect / measure distance:

- leg 0 set as input, with pullups disabled
- pull down resisitor across leg 0 and ground

Code sends a 10ms pulse, and listens for it's echo.
"distance" is measured by the delay of the echo in ms

Image
https://www.youtube.com/watch?v=Ps05LsqzzxE

Image

Distance value is around 1/3 the measurement in cm
e.g. distance value of 5 is 15cm

The sensor is good to around 2 meters

http://www.codebug.org.uk/explore/codeb ... onar-eyes/
Twitter @mikered codebug profile mikerr

mikerr
Posts: 81
Joined: Fri Jul 31, 2015 10:37 am
Contact:

Re: Sonar codebug - ultrasonic ranger

Post by mikerr » Sat Oct 31, 2015 10:45 am

I should add that the sensor only works reliably at 5v
it gets jumpy and inaccurate down to 3.5 and not at all at 3v.
Twitter @mikered codebug profile mikerr

Gyuri
Posts: 1
Joined: Sun Feb 21, 2016 10:21 am

Re: Sonar codebug - ultrasonic ranger

Post by Gyuri » Sun Feb 21, 2016 4:38 pm

How much resistance?

mikerr
Posts: 81
Joined: Fri Jul 31, 2015 10:37 am
Contact:

Re: Sonar codebug - ultrasonic ranger

Post by mikerr » Tue Mar 22, 2016 2:35 pm

Anything around 10k is ok
Twitter @mikered codebug profile mikerr

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