TONY NIXON 54964 wrote:
>
> This is not really a PIC question, but the project itself will be
> controlled by one.
>
> I need to measure a distance from a 'sensor' to a wall which will
> have a rough surface. The measuring distance should not be any more
> than 5 inches. The PIC will be used to control the 'sensors' movement
> across the wall and to gather the distance data, and thus I should be
> able to map the surface contour.
>
> It would seem a reasonable problem except that the wall will be under
> murky water. Also the wall may have mud sticking to it at places so this
> means I could not have a sensor which actually touched the wall. If
> this happened then mud may attach itself to the sensor giving me
> inaccurate data.
>
> Any leads on a type of sensor would be appreciated.
>
> eg Microwave, Laser etc.

Microwave does'nt work so well in water, and laser won't work in muddy
water. Try Ultrasonic transducers.

--
Friendly Regards

Tjaart van der Walt
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