Archive for December, 2007

The Sensor Bar

Tuesday, December 25th, 2007

Intially, I thought the sensor bar is a sophisticated piece of hardware that acts as the receiver of signals emitted from the Wii-mote and transmitts these signals into the Wii-console for processing. In that case, one would need to hack the Wii-console in order to pull motion tracking information from the device. Later, I realized that this is far from the truth. In fact, it’s the exact opposite – the sensor bar is actually the emitter of signals, and it is the wii-mote that is doing all the magic! For more information about the inner workings of Wii, check out the “Wii: Demythified” section.

To recreate the sensor bar, all you need is the following: two IR-LEDs, some wires, and a battery (can be any battery from 1.5V to 9V, although for larger batteries, you will need some resistors). Follow the following schematic diagram to build your sensor bar.

To save soldering, I used a piece of bread-board for connecting the components together. For durability, stability and asthetics, you should do the soldering and preferably mount it on a nice looking case, but that’s all optional. Here is what my final product look like:

I plan to make a video to show you how this is done. Stay tuned.

Update: I actually found a pretty good video on YouTube that teaches you how to do what I explained above to create a sensor bar (without wires) for the Wii itself.

embedded by Embedded Video

YouTube link to: Sensor bar explanation

Testing  Sensor Bar

Despite our sensor bar is extremely simple as a piece of hardware, we still need to test it to make sure we have connected or soldered everything correctly. If the IR LEDS are actually visible, this test would have been very simple – connect the battery and see if the lights would actually turn on. Unfortunately, IR lights are not visible to the human eyes. However, they are visible through a webcam. Connect a webcam to your PC and record a video of the sensor as we plug in and then the battery. If everything’s working, we should see the lights come up and then off through the view of the webcam.

Hello world!

Tuesday, December 25th, 2007

Welcome to – the ultimate guide to building your own Wii system and more!

The hardware list

Tuesday, December 25th, 2007

Here is a list of things you need to invest for building this system:

  • A Wii-mote ($39) – although the Wii console is scarce, the wii-mote seems to be plentiful in a local store near you (e.g. BestBuy, Walmart, Target, ToyRus etc..)
  • A usb bluetooth dongle (optional ~$5) – this allows the PC communicate with the wiimote. If you have a laptop, your laptop may already have built-in bluetooth capability, in that case, you will not need this.
  • >=2 IR-LED ($4) – for building your own sensor bar. You can buy these in your local RadioShack. If you buy them online, it’ll be even cheaper.
  • A Wii nun-chuck (optional, $19) - you will need this if you intend to play games that uses the extra input. Since currently, most wii games do not require a nun-chuck, I anticipate there will also be a lot of games that do not need this and therefore not including the nun-chuck as a must into the list.
  • Misc: some batteries, some wires, soldering equipment, some extra IR-LEDs if you intend to develop more advanced-applications. I also assume you already own a PC or a laptop