This year we’re using a Rev Robotics RIOduino to control some WS2801 LEDs. The advantage of the WS2801s is that they are individually addressable (you can control the color and intensity of every individual pixel separately, instead of control of the entire strip at once).
You can find multiple LED strips that use the WS2801 driver strips, but here is a link to a roll with good reviews on amazon, and here is the link to a library that lets you easily control them with the RIOduino, or any Arduino compatible board for that matter.
Another option is to use non-addressable LEDs like these (which only let you choose the color of the entire strip as a whole with the advantage of being about 1/3rd of the price). To control these you need some components that you can pick up at a Radio Shack.
Good luck, these sort of lights are a hobby of mine so feel free to PM me with any questions you might have!
We use Adafruit Neopixels (http://www.adafruit.com/products/1461). We use an Arduino Uno to control them, and they are very easy to use (source code can be found on the product page). They run off a 5V power supply, so we are using the old 12V-5V power converter from last year’s electronics (and it is legal to use, as long as you follow the Custom Electronics rules R30, R44).
We are looking at putting LEDs on our robot as well. Would using these and this switch connected to the 12V power distribution board and either color switched on depending on what side we are on for each match be legal?
We used a cheap kit I bought of Amazon for 25 dollars. I had to do a lot to make the legal though including cutting the ir receiver off and attaching a pwm connection to each side for easy removal(ir Is illegal during games) other then that it was just wired to the vrm and works great.
I just got some neo pixels in and have found them relatively easy to use. You do need a little programming experience to be able to make custom animations however the provided arduino libraries help a lot.
If you just want a few feet of LED in a single color, the quickest solution is to go to the nearest auto parts store and buy some LED strips (or other lighting solutions) in the detailing area. They’re also made to run off of not-particularly-stable 12V, so automotive electrical devices are often great for FRC - as long as they don’t violate an FRC rule, such as connecting 0V to the chassis. You then connect the red wire to M+ on a spike, the black wire to M-, and use kForward to turn the strip on, any other state is off.
If you want more, and/or a bit of programmability, the next step up is to get some of the long (1 meter or 5 meter) strips from SparkFun or another vendor preferably of the RGB variety. Googling 12V RGB LED strip leads to lots of people who want to sell these to you. These strips come in two main varieties - addressable and non-addressable. Non-addressable strips work just like the ones above, but they have four wires - one common (sometimes common anode (+), and sometimes common cathode (-)). Connect these to the output of four spikes, and different state combinations can give you black (off), red, green, blue, yellow, cyan, magenta, and white.
If you have common anode RGBs and code in java, you can use our Funlights.java as-is. Wiring is:
Relay R2 control wires from relay port 2
Relay R3 control wires from relay port 3
Common anode (possibly labeled +12V) to R2 M-
Red cathode (possibly labeled R) to R3 M+
Green cathode (possibly labeled G) to R3 M-
Blue cathode (possibly labeled B) to R2 M+
Addressable lights are also available, but you probably won’t want to tie up the needed time and other resources of the RoboRIO to do this - see a few posts up for some leads on how to wire and program these.
Last year and the year before we went with WS2811 strips driven by a Teensy 3. I worked with the kids and came up with a custom PCB to drive 8 independent strips, you can find that here: http://www.hackcasual.io/blingboard/
If you go with WS2811 strips, please don’t forget to add the filter caps to the power inputs. It will save you much heartache.
This year we’ve ditched the WS2811 strips for something a bit more… more. I’m just happy to have a reason to put one of our Beaglebones on the robot. We’ll be open sourcing the PCB, designs, and software for this years bling after our first competition, PNW Wilsonville DE6.