Solar Safety Bag Lights Up The Night, Charges Your Phone

Spend enough time riding a bike, and chances are good that you’ll start carrying a few tools with you. Even if you don’t, you’re probably going to use a bag to carry something along, so why not make that bag do triple duty? This convertible backpack/tote bag can charge your phone and provide safety lighting for nighttime rides. The design lends itself nicely to turn signals, too.

This bag was designed to show off the capabilities of Loomia, a line of prototyping parts made with e-textiles and other flexible applications in mind. It can be sewn, fused, or adhered to various substrates including fabric and wood. [AmpedAtelier] is using a Beetle microcontroller to control RGB LED strips using an illuminated Loomia soft switch on the strap. The switch is wired to the microcontroller through Loomia busses running through the strap.

Although Loomia’s site has a deep dive into the capabilities of their technology, it isn’t exactly open source. If that’s what you’re after, take a look at PolySense, which uses piezoresistive dye to create textile sensors.

15 thoughts on “Solar Safety Bag Lights Up The Night, Charges Your Phone

  1. Interesting, but I wonder how waterproof it is, getting caught miles from home in the rain and stuff (like you) is going to get drenched. Also I would prefer light up panniers.

      1. Whose being critical? First I wondered how waterproof it is, and the answer I’d like is very because this is a good idea and I would hate to see it let down by getting wet. Secondly I was commenting that I think panniers would be nice as the person who made this made it for bicycles and panniers are pretty standard for bikes, I was suggesting that panniers would be an excellent follow up project. So you see I wasn’t criticizing I was just questioning and suggesting. When I want to be mean you’ll know it. :)

    1. Yeah I’m deeply confused by it also, it looks like the bit coming out of the head tube bears most of the load but it can also rotate forwards and backwards at the bolts, then that forwards/backwards motion gets absorbed by the spring. I’m guessing though so if anyone actually knows and knows how much effective travel you get do speak up.

      1. That’s a Springer Fork.

        Popular some years ago. Abandoned for more effective suspension. Turning up in some retro designs, some Rat Rod builds, and on some modern slow moving cruiser designs. The odd person has thought they would be a cheap alternative to a modern suspension fork, put one on, and then thought they could go down a mountain trail with a rock garden, which quickly removes that expectation.

        With the trail of a fork having the axle somewhat forward of the steering axis, the Springer Fork is in the correct position when someone is on the bike, and the spring may or may not be adjustable depending on the implementation. The ones I’ve seen have a pre-load on the spring, so it doesn’t rotate/move-forward (trail) much when you get on. If you hit something that will want to move the wheel upwards, it does so against the spring by fork rotation, but that rotation also has a forward component – so you can see where it lacks efficiency.

  2. I love the optimism of builds like this. But why do we so rarely see a followup on how well it worked?

    So, looking at the specs, when the panel is perfectly aimed at the sun high in the cloudless sky, you can charge that battery at the C/8 rate, so you can get a full charge in a couple of good days. Or one long cloudless summer day, if you take a moment to re-aim it at the sun every hour or so.

    The standby losses from the circuitry as designed eats about 10% of the panel peak output, so you need about 2.4 hours of peak sunlight to cover 24 hours of standby losses. So, after a nice day in the sun you’ll have enough charge for almost an hour of light.

    1. If you ride a bike in -20 weather then you don’t need lights, the glow from the testosterone flowing from your massive brass balls should be good enough to guide you through the darkest night!

  3. I really don’t see why this is linked to bike riding.
    If you’re on a bike use a dynamo/hub-dynamo for your lights, buy a fancy one and you can also charge your phone with it.
    You’ll never end up with out proper light this way and you can actually see where you’re riding.
    Hanging a bag on your handle bar is one of the most annoying things during riding.

    Aside from that its a nice bag :).

  4. How exactly would the panel catch direct sun light when the panel is on the side? You might catch some during sun rise and sun set and some from head lights. Yor are etter off having them on your helmet. :P

    What’s the point of RGB anyway? You want the most efficent LED for this aplication. You are wasting power to drive ws2812b RGB.

    1. I believe the point of the RGB is signalling.

      You might be surprised just how much power a panel can generate while not properly aimed, does vary by panel type significantly and its nothing compared to what it would get on the correct orientation, but anything vaguely towards to sun can work actually kind of alright, and if its the right type of panel it will still function pretty damn well considering from just the ambient light if its not facing the right way at all (its a crap % of the panels potential, but its actually functional)…

      Does look like this will need some revisions to actually be in any real practical sense solar powered, but its not unusable as a solar powered device, just damn inconvenient with the tiny panel size relative to the power draw of those LED, and any phone charged by it – requiring user care to be sure it charges up enough…If you really want effortless convenience for something like this the panel(s) have to either be way oversized (so a second in the sun will run for a min etc) or always have some segment getting good sun in any orientation (not talking perfect solar tracking, but having say the available 3 sides of the bag all with solar cells so you will often have one pointing in mostly the right direction). Can also of course do some of both, which has to be the best option.

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