I purchased a Monovelo Monowheel a few years back. I believe they were first seen in the 2008 Beijing Olympics. The company that made them sold them to the public afterward. They come with or without leds in them already. If you get one with, you have 3 choices. Red, White, or Blue.

I didn't like that I couldn't control the lights inside. I wanted it to do some patterns and different colors and whatnot. So I stripped out what was inside, and rebuilt the LEDs from scratch, and this is what came of it.

This instructable will be in flux, as I am learning as I go, and will update the instructable as I feel things should be. I also have a few additions I want to add to the LEDs which haven't happened yet, and as I add them, they will show up here.

Some of those ideas are...
Adding a hall effect sensor to determine the speed of the rotating wheel to be able to time the light patterns to look still.
Put some sort of bluetooth with audio processing so the patterns will light up to music i am playing on my ipod/iphone.
Add a removable LCD faceplate that would ultimately allow me to pick from several preprogrammed patterns on the go! I could switch back and forth from the audio processing pattern to the programmed in pattern and vise versa without having the laptop around.

Here is the wheel in motion...

And here you can see a few vids of the lights in progress...


Step 1: Materials and Tools

materials include:

Monovelo Monowheel - Hopefully you already have this, but if not you can purchase one from Monovelo's site. The most expensive part of this project if you dont have one already.

Addressable RGB LED strips - 3 meters are needed. I used the LPD8806 which I purchased from adafruit.

Teensy 3.0 - This is the arduino, or controller for the LEDs. The teensy I felt was best over other arduinos because of its size. Even though it is so small, I was still barely able to fit it inside the monowheel. There are various places to get this. Kickstarter and adafruit are a few.

Screwdriver - for removing plastic covers on monowheel.

Soldering gun and solder - My wife and I have a Weller soldering gun and use solder wire that is a mixture of tin and lead with the rosin core. Handle the soldering gun with care. The end can get hot enough to burn you pretty well. Keep the tip away from your body parts. Also, if you use solder that has lead in it, wash your hands after handling. Lead is bad for your body.

Header pins - I bought these from the local electronics store but adafruit sells these. I'm sure there are other websites that sell them cheaper though. You need two 14 pin long ones (for the teensy) and a few extra pins. These are the long black bars with silver colored pins running perpendicular through them in the second pic. They have already been soldered onto the teensy in this pic.

Jumper pins - I bought these from the local electronics store also. I'm sure you can find them online, but you are on your own here. These are the rectangular block things in the second picture.

Clamp - Helped hold the LEDs in place while soldering. I used just a regular clamp, but usually soldering alligator clamps are used. And prolly better too.

Battery holder - 3 packs are needed that hold 4 AA batteries each. I purchased mine from the local electronics store but adafruit sells these.

Batteries (and charger) - 12 batteries are being used. I opted for rechargeables for two reasons. 1, this wheel will suck up batteries left and right using non-rechargeables. 2, the LEDs run off a certain voltage, and 4 rechargeables are in that voltage range whereas regular batteries go over and will blow the LEDs unless resistors are put in place. I did not put resistors in my setup, so please go with rechargeable batteries, or learn how to put resistors in the power sources. I bought this charger that came with 8 batteries and 4 more batteries on top of that from newegg. I get about 8 to 9 hours of full brightness life in my monowheel with these batteries.

LED on/off switches (optional) - But really cool, makes it look neater, and helps mount the battery packs better. If you choose to do the switches, three are needed. I bought these from adafruit. They have them in four different colors for your choosing. If you want a better switch than what the battery pack has to provide, but don't want the LED in the switch, a regular toggle switch will do, and will be easier to wire, but make sure it's at least a 3 amp switch.

multimeter (optional) - A good thing to have though. Use it to test the volts coming out of each power source (or battery pack of 4). The LEDs and arduino run off 5 Volts. Anywhere from 4.5V to 5.5V should be ok. 6V and you are going to blow the LEDs, under voltage and the colors will appear muddy. NiMH cells (the rechargeables I bought above) are rated 1.2 V each. 4 together is 4.8V, which is in our range. I tested 5.1 or 5.2 V out of my battery packs with the multimeter, so they are actually slightly higher than what they are rated. Alkaline cells (regular throw away batteries) are rated 1.5V each. 4 of those would be 6V which is too hot for our LEDs and ardiuno.

Micro 'B' usb cable and computer - The cable is used to upload code (to control the LEDs) to the teensy from the computer. The computer can be a laptop or a desktop, but much preferably a laptop because the teensy will be mounted inside the monowheel. Unless you can easily get a desktop close to your monowheel, a laptop is ideal.

Wire cutters/strippers - Self explanatory. But like any cutting tool be careful. It is potentially hazardous if you handle it incorrectly. Keep fingers out of the way when cutting things.

Tin Foil (optional) - Will be talked about in a later step. I felt it helped, but is not necessary, and also was a little bit of extra work.

Hot Glue Gun and Sticks - You are going to need a lot of extra glue sticks. I think I went through three packs of glue sticks for this. Like the soldering gun, the tip of the glue gun gets hot enough to burn you. Be careful with it and keep all body parts away from the tip so you do not get burned.

Small pieces of plastic - Or actually, anything that can be easily cut into little squares, is sturdy, can hold its shape, does not allow light to pass through it, and can be glued into the wheel. Preferably something non-metal. Cardboard would be a good one. I used plastic blinds that the cat messed up. This will be explained later but it NEEDS to prevent light from passing through. Thats where the black electrical tape came into play for me, but if you are using cardboard, you wont need the electrical tape.

Black Electrical Tape - See Above.

Pin Punch - Helped with removal of old LEDs.

Electrical Wire - 4 different colors are ideal. I used red, black, green and yellow. I didn't measure how much, but I'm guessing roughly 20 - 22 feet of each color. Two wires will be used for power, for these I suggest 20 gauge (18 gauge might be better for the current itself, but i found working with 18 gauge was difficult inside the monowheel.) I used red and black for power. The other two wires are to control the LEDs themselves, and 22 to 24 gauge will work fine for these. I used 22 gauge.

Insulated Quick Disconnects (optional) - I actually didn't use these, but I am planning to put them in in the future. I wanted to wire it so the 6 sections of the monowheel could be pulled apart. I started with male and female jumpers, but the gauge I got them in was 24 gauge and they were flimsy so I scrapped those and ended up wiring everything direct. So currently I cannot pull apart the sections. I will eventually put the disconnects in to make so it can be taken apart.

Price of Everything -

This project isn't too pricy, assuming you already have all the tools and the monowheel. With all that in hand already, the LEDS were $105. The arduino roughly around $22. I spent $73 for batteries and charger, electrical wire I spent roughly $15 for 96 feet of wire. The jumper pins, header pins, and battery packs were all only a few dollars each. I needed more glue sticks and solder and stuff... I'd guess I spent roughly $230 on this project.

If you don't have the monowheel, well your project price just skyrocketed another 18 hundred, and the tools? I don't know there, we had all our tools from before for previous things.
Thanks man! It's been a lot of fun, and a great learning experience.
That is neet

About This Instructable




Bio: I am an effects artist for major motion pictures. I moved up to San Jose four years ago with my wife for work. Work is ... More »
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