Arduino IR pointer (wii mote style)

Hello all!

This is my first arduino project and I’m very excited!

I want to hang a 48"x64" board on the wall covered in leds.

The user would then point a remote at difference areas of the board thus illuminating corresponding areas (like an interactive display).

I’m trying to figure out the best approach to determine where the remote is pointing.I can’t use the actual Leds as sensors as they will be behind plexiglass (or maybe I can?)

Plan A:
putting an IR sensor on each corner of the board, an IR Led on the remote. Then calculate the focus point by reading the 4 Leds.

Plan B:
putting an IR Led on either side of the board and 4 sensors in the remote. Calculate remote’s orientation based on how much IR light is seen by each Sensor

I believe the nintendo wii uses plan B which I would guess is more precise but it involves transmitting coordinates back to the wall which could be a pain.

I only need a resolution of 16x12 but I want the pointing system to be fairly precise.

Anybody tried this? Of coarse the best option would be just to experiment but I’m leaving for a 2week honeymoon tomorrow and would love to get your input in the meantime!!

Thanks so much for your input! :wink:

Great idea! Theoretically you should only need three photodiodes, since you are only triangulating, if I'm not mistaken. However, four photodiodes might make it more accurate. You will have to calibrate them somehow. You will have to make it take into account that you won't always be a set distance away from the board, so keep that in mind. You will probably want to play around with a single photodiode and plot the curve somehow. Good luck to you! Please take some pictures if you get it working!

Kyle

Thanks for your input Kyle! Maybe focusing the IR light to a small dot with a lens will help keep the beam size constant at variable distances...

I will give it a shot as soon as I get back! Best

Alex