Introduction: PixelLux- a 64 Pixel RGB LED Video Screen
Second Prize in the
Wow, I didn't think this project would be so looked at on instructables! thanks for taking a look :). I have a crappy video that I'll upload, but sadly I was an idiot and burnt out my teensy... so I'll post a video of the whole thing working later!
The following is a quick tutorial on how to build my PixelLux, an ultrabright, lo-fi, RGB LED video screen. Feel free to leave questions, comments, or suggestions! This is my first instructable, so any feedback is much appreciated.
What you will need for 1 PixelLux:
Arduino or Arduino based microcontroller (I used a Teensy++, available here)
64 Digitally addressable RGB LEDs
I suggest using a wholesaler on Alibaba, I used Schenzhen Rita Lighting LTD (Least expensive, longest wait).
Other options include Adafruit (A little more expensive) and Sparkfun (Also more expensive)
12 Volt DC, 10 Amp Power Supply (I got a 15A variable power supply from Fry's. It's AWESOME)
1/8" frosted plexiglass (available at a local glass store or acrylic store, should be a little smaller than the back)
20/22 gauge wire
Protoboard and/or pre-made PCB
32"x32"x1/8" Wood Board (for the back)
18x 32"x2.75"x1/8" Wood (for the inside and outside walls... I cut mine out of some lattice from home depot)
Tolex (to finish the light, I got mine from mojotone)
Aluminium corners (also for finishing- any hardware store has these)
4pin connector (I used a 4pin microphone cable from radioshack... but a USB should work too for smaller installations)
Cabling (the 4 pin mic cable wasn't sold anywhere so I had to make my own)
USB cable (for programming and microcontroller power)
Drill (and various bits, metal AND wood)
Nuts&Bolts(1/8" bolts should work)
Clamps (clamps everywhere)
Spray paint (I used black on the inside to make it look less wooden and more finished)
I have access to a lot of tools, which made this project much easier. If you don't have everything, don't worry... this project CAN be done with a drill, dremmel, hand saw, and clamps. you still need clamps. lots and lots of clamps. SO MANY CLAMPS.
Step 1: Building the Frame
The first step is to build the basic frame that will hold are led matrix. This is one of the most important parts of the project, and it's first, so remember- measure twice, cut once!
I went to home depot and found (in the moulding and trim section) some wide lattice that I cut in half to make two 2.75" wide boards. You'll need 9x 32" boards to make the entire thing, so make sure you buy enough of the lattice.
Take your bars and create a basic frame, clamping it together and supporting the middle with an extra board or two. Place larger pieces of wood on the outside of the frame (before the clamps) to distribute the pressure. Make sure the box is square, and glue.
When it's pretty dry, add the remaining 7 bars to create the y (or x) direction of your matrix. Be sure to make them as close to the same size as possible! clamp, and glue. Let this dry for a bit.
Step 2: Finishing the Matrix
With your remaining bars, cut slats to create the x direction. Cut them as accurately as possible, because they will most likely be off (I had to do quite a bit of sanding to get everything right). Measure and glue them in (see my picture for reference).
tips: have a friend help glue while you put them in. Mark where you're going to put them BEFORE you actually put them in- this'll save a lot of time in the long run.
Step 3: Cutting the Back
Before we commit to actually cutting the back board, let's go ahead and trace the inside boxes on the 1/8" back board. You might as well kill two birds with one stone and find the exact center of each square by drawing in cross-hairs. This helps for positioning the LEDs.
When you're done tracing the boxes, trace the outside edge so you know where to cut. Cut it, sand it a bit, and continue onward....
Step 4: Finishing the Back
This is kinda a multi-step thing, so bear with me.
First, you're going to want to drill all 64 holes in the back of the board. If you plan on tolexing your project, DON'T FORGET TO COUNTERSINK THEM. they should also be bolts, not screws (the bottom should be U shaped not V shaped).
After you've drilled the holes, go ahead and spraypaint this thing, though you only need to do it on the front if you're not tolexing.
When it's dry, lay it face down and put all the nails in, flip it over, and string the leds. They should fit JUST right, but you may need to make some new connecting cables. Be sure to check for those twisted cables!!
Step 5: Aligning the Matrix
Laying the matrix perfectly on top of your completed back, mark where the wires are (see pic). Using a dremmel, create little tunnels for the wires. Since I'm making two, I brought up an extra wire to have an input connector and an output connector.
Paint this next, align, and glue, being sure to use adequate pressure (bags of concrete helped with this... had to reglue a few times though :P)
At this time, you should also drill the output/input holes. If you plan on adding more units later, soulder a long cable from the bottom of the strip to the top so the input and output can be next to eachother.
Step 6: Final Steps!!!
Tolex your box if you want to... I used carpet glue and it works perfectly (and is wayyy cheaper and more readily available than the "tolex glue" crap they sell on the internets). Cover the back evenly first, lay the box down and clamp. Give it a good night's rest, and do the sides the next day.
When you're done with that, attach the metal wings drilling holes to take the plexiglass in to account. I embedded bolts into one side of the box so I could remove the plexiglass for servicing.
When you have everything done, peel off that brown protective covering and enjoy!!
Step 7: WHAT ABOUT CODE?
Oh, that's right. Code would be helpful right? Well, I'm still trying to develop my own based on the adafruit test code. I'm working closely with the developer of PixelController (an open source array controller) to create something to work with my specific LEDs, and I should have my code up soon :D.
If there are any master coders out there that want to help, I'd be greatly appreciative!!!
I'm now using adafruit's Adavision code and it's working pretty well.
I've been working all weekend on this stupid thing, only to figure out that my pixels are GRB, not RGB (meaning the colors are switched. I'm trying to figure out how to fix this at the most fundamental level possible. If anyone has any suggestions, I'd appreciate it greatly!
We have a be nice policy.
Please be positive and constructive.