[jnorby] knows what it’s like to leave the house with her baby in tow, only to realize that she has left something she needs at home. Instead of relying on a paper checklist, she decided to craft her own diaper bag that alerted her if she had forgotten to pack a particular item.
She built her bag from scratch, wiring small circuits into each of the pockets she created on the inside of the bag. Wires were run to each half of a snap fastener, so that they would complete the circuit when the snaps touch. The LEDs and snaps were then connected to a LilyPad Arduino, which checks the status of the snap circuits, lighting the appropriate LED once the proper item has been packed.
While we like the idea of a bag that uses functional indicators that remind you to pack items, we do think that the use of the Arduino, or any microprocessor for that matter, is massive overkill. We would ditch the LilyPad and snap fasteners for reed switches or perhaps normally closed micro leaf switches that turn the LEDs off once the proper item has been packed, rather than the other way around.
Actually I would think using a LilyPad with some sort of RFID combination would extend this capability pretty well. Overkill perhaps, certainly for a diaper bag, I agree. But to use a similar approach with RFIDS would be a military use (they already do this with pallets of supplies for inventory), or paramedical, or any number of other fields where your field- or ready-bag contains “ABSOLUTELY MUST HAVE” items.
I am unsure as to why this necessitates a microcontroller?
Don’t ditch the micro-processor, just add functionality to justify it :)
Perhaps add a thermal monitor to make sure the milk stays cold. Maybe tag the pacifier with RFID, that way if it’s missing from the bag for more than 20 minutes an alarm goes off to keep you from loosing the precious “binky”.
Maybe add bluetooth so you can check the bag inventory from your cell phone?
Can we stop telling people that their choice of platform isn’t right? Telling someone their choice of microcontroller or whatever is “massive overkill” is just a way of fraturing the hacker/maker community by implying that there are ‘cool’ choices they must make to win approval. It’s saying that simply choosing a platform they are comfortable with isn’t good enough — to get complete approval, they have to do it the ‘cool’ minimalist way.
Is this going into mass production? No? Then I think the Lilypad is a fine choice. Let’s stop stigmatizing beginners for sharing the projects they are learning on.
[jnorby]’s bag is sweet. I wish I’d thought of that when my kids were still using diaper bags!
Reed switches would require you to put magnets on everything you pack, and I feel like leaf switches would be prone to false negatives as to whether or not something was packed. I find a certain amount of irritation in calling the use of a microprocessor overkill simply because the project doesn’t take full advantage of it’s uses or features. LilyPads are $22, for all intents and purposes the things are almost disposable. Though I agree about the LEDs turning off instead of on, I feel as though this is a pretty reliable solution as is, and at the price it was made at, having a microprocessor on board is just a reason to find more cool things for your bag to do.
Coming from someone without a lot of component-level experience I can say that sometimes it’s easier to write code than it is to find good information on how to use analog circuits to perform simple tasks. I really like the HaD posts that feature a particular component and describe how to use it as it gives me a chance to broaden my component knowledge.
Oh God… $25 for a LilyPad when he/she could have used a simple NOT gate. That’s exactly what I don’t like about the Arduino: keeps beginners on a little bubble. I may use one, if I want rapid prototyping, but for anything permanent or sellable I would just keep it far away from my circuits.
I think the project is cool, regardless of whether or not it was done perfectly or to everyone’s personal standards. A project represents an idea, and that idea can be good no matter how it was accomplished.
Ideas can be improved for sure, not everyone can crank out flawless projects like the typical HAD comment thread poster… oh wait…
Is the human race now so completely stupid they can’t remember to pack a few simple items to manage a baby’s needs without a microcontroller?
How did the human race ever survive before the advent of the digital age?
Just a suggestion if this were to be revamped or someone was to do something similar. Use bicolor LEDs so you can see that everything is there, or, as the article mentions invert the logic so the lights are out when it is full.
@Charlie: Constructive critism is valid and respectful – even if you cant handle the truth :)
Ever heard of the terms “elegance” or “finesse”? You didn’t explain/reason why the lillypad was a good choice… just stating it means nothing.
Individual lights activated by individual switches on a 1 to 1 basis? Am I missing something?
Battery, current limiting resistors, switch, LED.
Done.
so all this does is light up LEDs when the snaps are closed, right? that doesn’t actually guarantee that you remembered anything at all. it just checks that all the pockets are closed..
useful for avoiding pickpockets I guess but totally pointless for ensuring that you’ve packed things.
I think any excuse to wire up a micro controller to something is a good excuse to wire up a micro controller to something.
I want to make something like this for my messenger bag, and all of the crap I lug to work every day. I have an arm7 development board that I’m not using for anything. I hope it annoys someone if I put it to work in my messenger bag =)
What Lunpa said.
Constructive criticism is one thing. But seemingly every time a project pops up using an Arduino to do something simple, the eye rolling and chiding starts. The complaints are getting so common and predictable that Mike feels that he needs to preemptively apologize for posting a hack that features an Arduino being wired to some lights. That’s a pretty good indication things have moved beyond the level of constructive criticism. Sometimes the beauty of a good hack is its flawless execution, but sometimes it’s just someone had the moxie to make their idea a reality. I mean really — where’s your diaper bag with indicator lights?
Why is a Lilypad a good choice for this project?
It’s a good choice, because if you insist on rigid standards of design for every single project you do, most of them will never get done. And a LED-enabled diaper bag built with a Lilypad is better than no LED-enabled diaper bag at all.
It’s a good choice, because maybe jnorby likes using a Lilypad. Or maybe she wanted to know how to use a Lilypad and needed a project to experiment on. Or she had a Lilypad lying around.
It’s a good choice, because when jnorby decided to add reminder lights to a diaper bag, maybe she didn’t know how, but found some easy examples to follow using a Lilypad, and then made it work.
I don’t know why she chose a Lilypad. Certainly every choice comes with pros and cons. But the fact that she ended up with a diaper bag with functioning reminder lights is all the proof you need that it was a good choice for this hack.
If you want to offer constructive criticism, try something along the lines of, “Hey, did you know that you could use really cheap NOT gates and get the same results? If you change it, you’ll have an extra Lilypad lying around for your next project” instead of “Massive overkill” and “That’s what I hate about Arduinos.”
The first thing I thought when I read this is exactly what the first poster said: this would be awesome with some RFID tags on each important item. That would be simple to implement, but the power source may become an issue of weight.
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How would you implement NOT gates for this? Is the NOT gate just used to invert the status of the LED? Or does it somehow identify the items in the bag and help with tracking? This is a legitimate question.