Intro: The Green Helmet (Solar Powered, Safety Lit, Weatherproof Bike Helmet.)
A solar powered, trickle-charged, weatherproof, safety bike helmet with changeable parts.
> See 45 second video of helmet
> 2-minute video of construction and use
> Charge time: 5-8 hours in full sunlight to charge 4 AA batteries. I used 3 AAA batteries, so it charges in more like 4 hours. It will charge in bright cloud cover as well.
> Runtime being tested, but so far, seems like several hours.
> Replaceable 5 or 10mm LEDs, flashing or not, in O ring sealed mounts.
> Flexible weatherproof solar panel.
> Detachable batteries and panel for use as a AAA battery charger for camping equipment like headlamps that use 3AAA batteries.
> Removable the AAA batteries can be easily taken out and charged in wall if needed, or regular AAAs can be used.
I thought this would be a well-suited application of solar powered trickle charge panels. I only ride at night about an hour a week, so during the day the helmet can sit in a window and charge. Helmet mounted lights also free me from having lights mounted on my bike that need to be detached to keep from being stolen. It works in the rain and so far is always charged when I need it.
This project could be done in many different ways and I spent a lot of time trying different parts and ideas. The key breakthroughs for me were to use 3 AAA batteries, vs the 4AA's that came with the Solar Panel because they were a better balance of weight to the right amount of power and milliamps. I ended up using a simple soft case Velcro wrapped to the helmet, and relied heavily on Black Shoe Goo! (I think it's the new duct tape). Most of the work was getting an easy rapid prototype idea to work rain or shine, for months on end, and be versatile with replaceable parts. I kept it flat black because the helmet is flat black, so chips don't show. And I'm in New York City, where black is the default color.
Good luck! Let me know if you come up with better ideas.
Caleb John Clark. Made at NYU, Tisch School Of The Arts, ITP dept. for Build in Despina Papadopoulo's Softness of Things class
Oct. Nov. 2007
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Step 1: Parts & Tools
Helmet: Bern black Brentwood with visor pads for summer: http://www.bernunlimited.com/2007/brentwood.html
Solar Charger: Flexible Solar Battery Charger SolLite-4AA by Silicon Solar. (I used a different case with 3 AAA batteries). http://www.siliconsolar.com/Flexible-Solar-Battery-Charger-SolLite-4AA-p-16199.html
> 2, Giant 10mm Rainbow Flashing LED: Flash slow, then fast, through red, green and blue. Electronic Goldmine: http://www.goldmine-elec-products.com/prodinfo.asp?number=G16226
Or if you want a longer run time, use regular single color flashing 5mm bulb, say green in color from the sites below.
> 2, Red Clear 10mm Flashing LEDs. Electronic Express: http://www.elexp.com/opt_6bid.htm
> 2, Yellow Clear 10mm Flashing LED. Electronic Express: http://www.elexp.com/opt_6bid.htm
- You can also buy all the colors and rainbow flashing bulbs here: http://www.allelectronics.com/cgi-bin/category/340200/Flashing.html
- and 10mm here; http://www.goldmine-elec-products.com/products.asp?dept=1093
Waterproof, replaceable bulb mounts. Takes 5mm or 10mm bulbs.
6, White 10mm 24 inch wired mounts: 593-CNX460X24124 CNX460-X02-4-1-24 VCC LED Lens Mounts from Mouser Inc. http://www.mouser.com/search/ProductDetail.aspx?R=CNX460-X02-4-1-24virtualkey59300000virtualkey593-CNX460X24124
LED Mount Lenses
Clear Water Tight O-ring Fresnel lenses: 593-HMS462CTP HMS462CTP VCC LED Lens Mounts: Mouser Inc. http://www.mouser.com/search/ProductDetail.aspx?R=HMS462CTPvirtualkey59300000virtualkey593-HMS462CTP
Radio Shack: "AAA" Battery Holder (Holds 3 Batteries)
Item #: AC-1100-270-0412
Switch: Radio Shack DPDT Submini Slide Switch. Model: 275-407
3 high quality rechargeable AAAs, Ni-Cad seems the choice of lots of solar products.
9 volt battery snap connectors
2, nine volt battery connectors. http://www.radioshack.com/sm-fully-insulated-9v-battery-snap-connectors--pi-2062219.html
Soft Case: Case Logic MP3 Mini Disc Player Shuttle: http://www.caselogic.com/small_mp3_player_shuttle/product_detail/index.cfm?modelid=56457
Black Shoe Goo: To fill in around mounts and reinforce/waterproof solar panel connectors, and soldering and switch on battery holder: http://lifehacker.com/software/household/shoe-goo-super-glue-157137.php
Standard 'gap filling" super glue for LED pre-Shoe Goo mounting, wiring and reinforcing Velcro edges
Standard Black Double sided Velcro
Reflective Velcro bike wrap
black shrink tubing (electronic stores)
Krylon ultra flat black spray paint. (hardware stores, could use gloss Krylon "Fusion" paint too)
Step 2: Install LED Mounts in Helmet
Before you start gluing, test the LEDs in a bread board, or 3AAAs in a case, or a 4v power source, just to make sure it all works.
The Shoe Goo is for holding and building in the mounts, but also the mounts are placed so as to let air in the front two vents still, and a little out the back and top. You could put lights in all the vents I suppose. Or skip the top ones altogether.
1. Sand 2 of the LED mounts ribs off on two sides. These are for the top two lights so they fit into the tight vents
2. Super glue the six mounts into the vents. I used "gap filling" supper glue. Super glue dries fast, so place them where you want them and then hold them until the glue sets. Let dry. Make sure the O rings can be unsqrewed!
3. Shoe Goo in the big holes. I had to do one at a time since Shoe Goo flows with gravity. So I mounted the helmet in a vise, with one vent pointed up, taped the backside of the helmet's vent, and filled the gaps. Then let it dry for 24 hours. Then repeated for each vent.
4. Spot super glue wires into the air vents of the helmet.
5. Put another layer or two in vents where the Shoe Goo settled.
Step 3: Reinforce Solar Panel
I broke my first solar panel from moving around the leads that connect to the panel too much.
On my second panel I reinforced the leads with...what else...black Shoe Goo! Both on top and underneath.
Step 4: Velcro
Now it's time for putting the Velcro on the Panel and helmet. It doesn't really matter if you painted or not. You'll have to paint as a last step anyway.
1. I put the fuzzy side of the Velcro on the Solar Panel. I don't suppose it matters. Either way, start with the panel. I used six pieces of Velcro running perpendicular to the where the wires leave the panel, and dealt with the overlap at one end vs. ripping the last piece. It's hard to cut.
2. Mount other Velcro side to the Panel's Velcro, NOT the helmet, this will insure alignment.
3. With the solar panel's bottom showing the sticky (as in glue) side of the Velro, place it squarely on the top of the helmet. Press down hard on all sides.
4. Separate the solar panel from the Helmet, leaving one side or the Velcro on the helmet. Now fix up the helmet Velcro.
5. I edged both the solar panel's Velcro and the helmet's Velcro with super glue. I figured it would keep water from seeping in, but also mean I could someday get the Velcro off of the helmet much easier then if it'd glue down the Velcro on the entire surface.
Step 5: Wiring
I tried 3 different tactics for holding the back batteries. First I tried solid plastic containers for holding wallets when camping/rafting. I was going to mount them directly to the helmet, but be able the take the batteries out of the container. After sever cases and lots of glue, it proved not the way I wanted to go. So I found the little soft case to Velcro on, much better. Could even be smaller.
Either way, the wiring is pretty simple since there's no chip.
1. Get the six white and six black wires twined together.
2. Put on some shrink tubing, like 4 inches.
3. Solder and electrical tape about 8 inches of red wire to the white wires, and black wire to the black wires.
Battery holder to panel connection
Use the black and red wires that come with the battery holder to attach to the solar panel's wires I kept them slaved together since I figured I'd have the batteries with the panel mostly, but you could put any kind of connection. You're going to need an extension of wire too, so two solder joints.
I went from 4 AA's to 3AAAs because it worked fine and was light. I think you'd need about a 150ohm resistor if you went with 4AA's because I burnt out a bulb or two.
1. Cut the 4AA charger that came with the panels. (or if you don't mind the weight, just use it. But beware of the watts, they can blow LEDs)
2. Solder about 8" of red and black wire to the panel's wires. Tape.
3. Put on about 8" of shrink tubing over the joint, close to the panel.
4. Run the wires up into the battery case's hold for ear phones.
5. Then solder to the AAA battery holder's wires and tape.
Power and Switch
Now we've got to get the power to the lights and put a switch in. You could use a variety of switches and cases here, but here's what I did.
1. I carefully soldered red and black wires of a standard 9volt battery clip to the battery case's leads at the same place the leads that came with it attached. However, since I used 9volt battery clips to make it detactable, I soldered Red to black, and black to red And be very careful not to melt the plastic. I did, and had to buy another holder. Cover everything with black Show Goo. Let dry.
2. I mounted the switch with...you guessed it - Black Shoe Goo! Be careful not to glue the switch though. I had to stand around moving it every once i while until the Goo set. You could also super glue it, but that ruined one switch for me.
3. Cut the black wire and wire it to the switch on both the 9volt clip end and the battery case end. Solder, cover with more black Shoe Goo!
4. Once it's all wired, and it works, heat gun the tubing to tighten it around the wires.
Step 6: Paint
Now a final coat of ultra flat black paint and we're done. I used ultra flat black to match the original paint on the helmet, the black Shoe Goo, black solar panel, and black case. This way cratches won't be visible. You could use any color though, if you put a few coats on.
1. Buff, bondo, Shoe Goo, very carefully sand, any bumps or blemishes.
2. Detach panel and case.
3. Tape up Velcro to cover
4. Take off O ring lenses and wrap LEDs in tape, or take out LEDs and cover holds they go into.
5. Wash with rough sponge, rinse, dry
6. Spray paint. Let dry a full night.