Help with decorating uni for night time light parade

General
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Every year our local unicycle club participates in a parade called The Parade of Lights. It’s held at night around Thanksgiving and usually has a Christmas holiday theme.

This is the first year I’ll be participating, and I wanted to do a little more than just hook up a string of battery powered LED Christmas lights attached to my unicycle spokes and wear a silly hat.

After talking with a club member this weekend, I learned that the cycling club always shows up the unicycling club with extravagant decorations. That was all it took for the wheels in my head to get spinning, and now I have a purpose other than just participating. I got to represent, yo!

This post may be a bit outside the norm for this forum, but hopefully you can appreciate the spirit in which I come to you with this. We also have some pretty darn intelligent folks here, and I think some of you may have the experience I need for what I have in mind. There are also challenges to decorating a unicycle that only a unicyclist can appreciate! If you’re not interested in digital technology, microcontrollers, etc., you might want to skip this one. I’m gonna jump off the deep end here for a bit…

I’ve dabbled in electronics most of the my life, and I have excellent computer skills, but most of that was geared towards managing computer networks and engineering them. I haven’t had much of an opportunity to deal with programming microcontrollers to control lights, music, etc, but that’s what I’d like to do with this project.

Currently, my plans are to use an Arduino microcontroller board to control LED lights, maybe something like Adafruit’s NeoPixels or DotStar LED strips, and probably synchronized with music. Just want to make a cool light show. The LEDs are going to be attached to either clothing or the unicycle, or both, and it needs to be battery powered. If possible, I might want to synchronize it with music.

I’ve read a lot about this, but I haven’t played with any of this technology yet in my own hands. I’m not married to the idea of using an Arduino, but I’m leaning towards it as it’s marketed towards people like me that don’t have much experience programming microcontrollers, and there’s tons of online support for it.

If you have any experience with this sort of thing or have any suggestions for how we might show up that cycling club, I’m all ears!

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Might be a good place to start although I wouldn’t do exactly this:

ATtiny2313 was hot stuff in 2007 and I’ve got one in the breadboard next to me right now, but there’s better stuff without the painful memory limitations. A classic ATmega328 Arduino ought to be terrific for this, although it’s even a little dated these days.

I’d think about using an accelerometer to sense gravity instead of the magnet and Hall effect sensor. I usually cheap out and buy that junk from generic vendors on eBay.

Need pics when you do it!

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Update: Looks like this is a newer tutorial using more recent hardware:

That’s supposing you like the idea of displaying messages and stuff on your wheel.

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Awesome! Thanks for the links as well as the advice about the accelerometer. That gives me some ideas, and I’m all about the cheap stuff. I bought a Chinese made Arduino UNO R3 board (supposed to be the latest and greatest from Arduino) as part of a kit today to learn how this stuff works. The board is branded “Inland”, and individually is selling at MicroCenter for $6 (the board by itself, not the kit). The kit came with all kinds of stuff like a couple of bread boards and lots of LEDs, including one that’s an RGB. It also came with a servo motor and a stepper motor and all kinds of other kizmos. You can check it out here.

My wife and I set it up and uploaded some programs on it to play around with a few LEDs responding to settings on a switch, a POT, and an analog joystick. It works really well, and there’s lots of support for it online. I can’t wait to see what else we can do with it.

Regarding the bicycle wheel POV tutorial, that’s definitely going in the right direction, and that looks pretty straightforward and relatively easy. Sadly, I don’t think my unicycle wheel will spin fast enough to create the effect they are going for there (especially in a slow moving parade), but there may be other effects I could use with a similar setup.

You’ve definitely given me some good stuff to think about, and I’ll be sure to post a video or something to show off whatever I’m able to come up with. We gotta put those cyclists in their place this year! :wink:

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This unicycle at Unicon 16 in Italy (2012) had a rotating mirror ball, a sign inviting you to the “Handle Bar” for a drink, and an LED system of some sort that could do messages or images into the wheel. What my camera’s shutter cut down there was an image of the Unicon 16 logo. It was really, really cool and I wish I’d taken a video or more pictures!

This one shows the Unicon 16 logo:

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Cool! Good stuff!

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I’ve got a UNO (oddly enough it happens to be a genuine Made in Italy one) right next to me, being used at the moment as a programmer for the ATtiny2313 I mentioned before. The ecosystem of tutorials and code libraries for it is great. Being abie to use one Atmel chip to hack another one is cool too.

Neat! It looks like I’ve managed to get most of that a la carte plus plenty of other stuff. :slight_smile: You can have lots of fun with that.

Sure, try it and see what happens. I’ve never taken part in a parade but I’ve seen comments here about riding around in circles to keep moving because parades sometimes go uncomfortably slowly. Maybe that would help with the POV effect.

And like you mentioned at the start, those NeoPixel strips seem like a good plan for getting lots of LEDs connected to one controller board which doesn’t have a huge number of digital outputs. No experience with them myself though…

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Using the UNO to program the ATtiny2313? That’s cool! :slight_smile: I’ve got a few Raspberry Pis, and I saw instructions for using them to program an Arduino, but for now it’s most convenient to use my laptop.

Oh yeah, lots of riding in circles. No way around that!

I’m also an avid photographer, and there are some really neat things you can do with moving lights and long exposure to “paint” in the air. The picture below is from the tutorial link you sent me. They just took a single long exposure as the girl rode by on her bike. This photographic effect would work just fine with a unicycle as well since rotational speed isn’t as critical for a single, long exposure. I’d probably trigger a flash in the middle so you could see the unicycle in the shot.

I don’t have any experience with it either. I’ll just have to experiment (yay!). The NeoPixel refresh rate isn’t fast enough for the “POV” effect, but the DotStar strip is, but it’s a more expensive. I’ll just have to play around with it and see what fits best where.

Ideally I’m hoping to come up with something that doesn’t break the bank so that other uni riders in the club can do something similar and maybe we can get a theme going for the parade and really show up those bicyclists! There seems to be no end to where you can take this.

projects_Bike_Wheel_POV_Display_adafruit_01.jpg
projects_Bike_Wheel_POV_Display_adafruit_01.jpg800×600 105 KB

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It tickles me every time! My Arduino software bundle (pretty dated by now, v. 1.0.3) has a sketch called ArduinoISP in the “examples” directory. I’ve used it with avrdude to put bootloaders onto unflashed chips, to load non-Arduino applications on an ATmega644 chip, to prototype stuff on a bare AVR chip stuck in a breadboard, etc. Proper device programmers aren’t particularly expensive but I always feel like I’m getting away with something when I can get around buying one.

OK, cool. Now you’ve got me interested. I’m thinking it could be fun to set something up on my Coker and roll around town with it. :slight_smile:

What’s the wheel size on the unicycle you’d be putting this on?

DotStar looks like a huge step up if I’m reading this right, and maybe the price difference now isn’t what it was when that guide was written. Picking comparables more or less randomly, I see a 1-meter 60-LED NeoPixel strip at Adafruit for $25 while the same thing except DotStar is $30, which doesn’t look like a back-breaker for the extra performance with simpler interface you get. (And a few seconds on eBay turned up a US-based seller with the same thing - listed as apa102c - for $20 w free shipping.)

These guys say, “APA102 - (adafruit sells these as dotstars) Fast data rate (I’ve pushed as fast as 24Mhz), stupid high refresh rate. I’d recommend these over just about anything else at this point.” So supposing they know what they’re talking about…

I’d really enjoy hearing about where you go with this if you feel like posting or PM’ing updates.

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Cool! :slight_smile: I’d most likely put it on a 24" wheel. I thought of the 20", but I think that would be brutal to ride any distance, but I think anything larger than a 24" would be too fast and harder to maneuver in tight circles.

Very cool! I’m always happy to save a bit here and there, and I appreciate all the extra info and links you’ve given me about where to get comparable hardware on eBay for good prices. Sa-weet! :slight_smile:

Of course, and likewise! What fun is it if you can’t show it off, right? :wink:

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I know this isn’t what you are going for, but when I see people mention lights on a unicycle I instantly think of EL WIRE!

Not sure if you’ve seen it before, but it might be worth checking out :slight_smile:

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I recommend using neopixel LEDs if you go for the led route, see

these are very easy to program using for example a triket. The uno is a bit bulky for integration in a wheel.

I have tried using monkeylectric which is not too expensive

it turns out however that the wheel turns too slow for the effect to be visible. The elwire is also a nice option but the light may be a bit dim so you will probably want a lot of it. Spokelights are also nice and easy to install. I have a few and the effect is really nice.

i would love to see the result… have fun!

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That’s a really good point. I don’t know much about the Trinket but I had thought of the “Pro Mini” form factor boards, with the same cpu as the UNO and they’re tiny. The UNO would be great for experimenting and prototyping, but for a few extra dollars, a board could be dedicated to the wheel installation. Directly soldered connections are also likely to be more reliable than plugging wires into the female headers on a standard Arduino.

You still need to put a battery somewhere though.

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This guide is well worth the read:

I have made some wearables and did some led projects and found that neopixels are much easier to use because you can string them together and do not have to power them individually.

El wire is also well worth the try. I have found this site which looks promissing http://www.elwirepros.com/customer-photos.html

And here is an aritcle of a guy using paint.

http://www.fietsverlichtingwinkel.com/c-2724515/glow-in-the-dark-bike/

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Have you tried the DotStars? They’re supposed to be even easier to interface and also refresh faster. I’ve never used either.

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Thanks, Juni. I haven’t seen it in person, but I’m familiar with it and seriously considering using it somehow. It seems very cool!

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Yes, I’m looking at both Neopixels and el-wire. I may use a combination of both. Good idea! :slight_smile:

I’m looking into those as well. Probably don’t need the faster refresh rate for what I’m doing, and they are more expensive than Neopixels (but not much). However, I am considering putting the DoStars on my bike for those cool POV effects! :wink: We’ll see where it heads, and I’ll be sure to post pictures!

No, that’s totally cool. Definitely considering el-wire as part of it. :slight_smile:

Yeah, the Uno is too big to put in the spokes, but it might fit under the seat for controlling LEDs on the frame. Currently, I’m considering Adafruit’s Trinket Pro, the Pro Mini, or something comparable. That seems to be a good fit.

Cool!

Great ideas from everyone. This is turning out to be a lot of fun. I like to tinker and learn how to do things like this, and it’s branched out into other projects that have nothing to do with my original project. I’ve already had a lot of fun with the Uno controlling servos, LEDs, sounds, 7 segment LED and LCD displays, temp sensors, etc. This is super-cool stuff! :wink: My coding skills are a bit rusty as well (I was never that great at it to begin with), and it’s been good to dust off some of those neurons and put them back to work.

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Yes, I knew you knew about them because I found out about them from you! :slight_smile: I meant that as a question to janvanhulzen, who recommended NeoPixels after we’d had our exchange on DotStars. Sorry, I should have been more clear about where that was directed.

Indeed it is! It seems a lot different from my attempts at hobby electronics way back when. The knowledge you can find online changes everything, and new things are popping up every day, mostly priced lower than a mediocre meal out. I’m starting to try my luck with some of the 32-bit cpu stuff, where it seems that a lot more is “left as an exercise for the reader.” But that’s building on (false?) confidence from successes with the AVR family. Arduino is a heck of a gateway drug.

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Check out what some of the night time rc heli people use, they have many of the same problems as we do. Also, if they say a certain product is too bright when run at a certain voltage, when they fly hundreds of feet in the air, you can bet it’s bright enough for unicycling in a parade. Link to a forum here

Also, if you haven’t thought about batteries, I would recommend LiFePO4 cells. You could also run a LiPo, like my brother did on his led unicycle, but you run the risk of creating a ridiculously hard to put out fire, with black, carcinogenic smoke.

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Thanks for the info, Superbant. I’ll keep all that in mind.