Solar LED Bike Bag

I had the opportunity over this past summer to work the night shift at a bakery a few towns over, which meant I had a lot of commuting to do. Back. And forth. At night. On a bike. The buses don't even run that late. I got pretty fed up with continually getting forced to the side of the road by all those damn inconsiderate drivers speeding by - how could they blast past the presence of so earth-conscious a being as myself with such little regard, cruising about in their dirty, carbon-polluting machines?! Of course it probably wasn't all too easy to see me, given the general lack of street lighting in the area, so I went and got the requisite overpriced head-and-rear-lamp kit.

And ate through batteries like pigs at the trough. I didn't want to keep buying all those damn batteries, and I sure as hell didn't want to keep tossing them out, so this is what I came up with. That and the fact that I wouldn't be going to Burning Man this year left me with a bunch of free time that would otherwise be spent thuswisely. So this is my consolation prizes, of sorts. I will be adding on an implementation of Leah Buechley's wonderful Arduino-conrolled turning signal bike jacket in the near future.

This is my first Instructable, and its a retro documentation job, but I hope it suffices. If it seems a bit too dumbed down, then by all means it probably is. That extends to me as well.

Anywho, Create and Enjoy!

Oh and, apologies for the terrible quality of the images. I've worked my camera pretty hard over the years, and it seems like its pretty near the end of its product lifecycle. sniff.

Step 1 Stuff You Need

Materials/Supplies
1 Backpack/messenger bag
1 Project case
1 Cheapo LED headlamp
1 Cheapo/not-so-cheapo red LED backlight for bikes
2 3V, 50mA PowerFilm Solar Cells, product number MP3-37
1 AA battery holder, capable of holding:
3 NiMH AA batteries
1 Piece of perfboard that will fit into the top of the project case
4-8 Standoffs + screws
1 Standard blocking diode, 1N4001 for instance
5 100 Ohm resistors
3 Momentary pushbutton switches
1 DPDT switch
1 SPST switch

Lots of:
LEDs, to your choosing
Wire, to your choosing
Spare batteries, for testing
Solder
Thread (heavy duty nylon, if possible)
Velcro
Boredom

Optional:
1 Arduino Skinny from sparkfun (or the new certified version, the Arduino Pro)
Pounding Psy-trance

I had a cheap backpack from Burton Snowboards which was the perfect size for my purposes, but didn't like the straight "backpack" style. So I rearranged the straps and now its been tilted on its side as a messenger bag with one main body-hugger strap and an auxiliary strap that latches in from the bottom, providing a remarkably secure platform. The biggest downside so far is how it tends to wrap around the body, resulting in a thoroughly sweat-soaked shirt. But, uh, whatever. It works. I found a latching, air-tight tupperware-type container in the kitchen that was perfect for the project box, and the headlamp, I picked up for something like $6 from WalMart. Pretty much everything else was in my gear box or ordered in online. The majority of my wiring is a bunch of speaker wire I had lying around, nice and resilient.

Tools
Soldering iron
Breadboard, for prototyping
Basic multimeter
Screwdriver set
Cordless drill + bit
Alligator-clip jumper wires
Needle-nose pliars
Wire cutter
Sharpie
Lighter
Needle
Xacto blade
Serious industrial adhesive
Duct tape
Wire hanger, like for coats and shirts

Optional:
Soldering iron holder/third hand
Hot glue gun + hot glue, for sealing purposes
Hacksaw, the better to cut with
Scissors
Adequate ventilation, for to preserve your precious grey matter

Comments

[Ghost Wolf]

Smashing idea! I'll going to make a rechargeable camera bag based off your idea here during the summer.

[steve_the_engineer]

I respect the innovation and environmentally-friendly transportation, but I think you need to rethink the 'battery-charger'. It may 'work' for now, but there could be a failure and a possible fire caused by the lack of regard for safety when charging the batteries. You also should consider that others may attempt this with different solar cells or batteries, which may be more likely to fail. A suggestion, there are many ICs available that do exactly what is needed in this situation. Look for something that charges the NiMH batteries and has an integrated buck-boost regulator. This will be magnitudes more efficient than your current setup. Steve