Multitouch 2 – Infrared light

For the project mentioned before I needed an infrared light to be able to reflect light off the fingers to the WiiMote camera. I started building this myself but being my first electronics job ever I needed some help. After reading and asking around for tips, the circuit I needed to create looked something like this:Basically two infrared serial LEDs + a 68 ohm resistor for each pair. What I wanted to do next was to power the whole thing off USB to make it more portable. This meant I needed to keep it under 500 mA not to create a power surge. So, in the end my project included 16 LEDs and 8 resistors. Below you can see the result of my work:

I am not very proud of my soldering skills yet so I will not show the backside 🙂

At this point I started testing it. I connected it to USB, I connected the WiiMote to Bluetooth and downloaded the WiiMote Multitouch example written using DirectX to display and manipulate a grid on the screen.
The whole thing is not precise at this moment and I can spot two main problems with it:

  1. I didn’t do the whole in the middle yet, which means I positioned the WiiMote on top and the light is not reflected at a convenient angle.
  2. I didn’t get reflective tape yet and my fingers create too many points to track. Out of all these, the WiiMote is only capable of tracking 4 which means they keep changing all the time, making it impossible to control.

I ordered reflective tape on eBay UK, it will take a few days but it’s very hard to find in the Netherlands. Meanwhile I will start developing other features and get back here when possible. To be continued…