Hello, I’m just looking for some advice from anyone has experience with proximity sensing and wireless connectivity.
basically my project consists of two poles with an AVR chip in each.
I’d like to be able to detect proximity of the ends of each pole to each other. sensing only needs to happen when the ends are less than 12" from each other.
I’m considering IR but that seems fairly directional so they would have to be end to end like so ( ---- ---- ) -the *s represent the sensors/emitters. Ideally i’d like the sensing to be omnidirectional so if the sensors are anywhere within 12" or so of each other it would still pick up on it.
Ideally this could be a valid arrangement as well :
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It would be really great if the signal could be stronger the closer the poles were to each other and weaker as they get further away. I’m thinking maybe some analog signal utilizing the ADC of the AVR uC.
Also the cheaper the better…
maybe I could diffuse an IR LED a bit by roughing it up with sandpaper or encasing it in some kind of plastic that would diffuse the light. though can IR be diffused like normal light? also I don’t really need to be able to distinguish between which end is what but if that’s possible, that would be cool too.
One more question while I have your attention. I’d like to be able to wirelessly communicate between the two AVRs in each pole. range for this only needs to be maybe 20feet max though really 10 would do it. I’ve been thinking of some kind of cheap RF device. data transfer rates between the two doesn’t need to be very fast at all. I’m already using UART to communicate to a PC through bluetooth so i think whatever I end up using will have to be bit-banged unless i can somehow use 2 UART devices on with one AVR. So again if anyone has any recommendations for a cheap and simple to integrate device, I’d love to hear your opinions.
Thanks,
Jeremiah