With an El Niño event in full swing those of us in the northern hemisphere have just had a roasting hot summer, and those in the southern are about to have one. We know what that means, even with the best laid plans the slightest bit of exercise is going to raise a lot of sweat. And if you’re carrying a backpack that means a soaking down your back. Never fear though, because for that one, [Crafterboi] is here with a fan-assisted back protector.
The idea is simple enough, an open framework that sits between you and the backpack, allowing air to flow. If that weren’t enough, there are a couple of 5 volt fans at the top to blow air through the space. It’s printed using PETG, because as he explains, on a really hot day some surfaces can exceed the temperature at which PLA starts to soften.
We like the idea of this project, but what we especially like is that his prototype was made of a pizza box. ten out of ten for resourcefulness! Meanwhile this isn’t the first time we’ve seen a cooling backpack as others have had Peltier systems and evaporative coolers. We would link you to them, but sadly those are both from Hackaday’s early years and link rot has taken their websites.
I wonder how long it will be before aliexpress liquid-cooling garments with e-scooter battery packs and mini-fridge compressors become affordable. Has that been built on HaD before?
Inspired by Neal Stephenson’s Earthsuit? (from Termination Shock)
I’ve never read that so I could’t say.
However there are already liquid-cooled ‘garments’, but they’re more ‘PPE for Seriously Hostile Environments’ rather than ‘Personal Cooling for Hot Summer Days’, and the prices reflect that :)
I’d be nervous with Freon/adjacent and a compressor on my person. Peltiers, properly heat-managed, just seem … better.
Peltiers are too wimpy.. Idk plenty of people have a fridge in their room or at least down the hall, I don’t think having refrigerant nearby is that scary.
Some refrigerants are flammable, but there are plenty of non flammable ones.
Well, none of them are shaking around while climbing hills…
They’re soooo inefecient though.
When you’re carrying the batteries that run it, it’s a difference of probably over double or more the runtime
I certainly would prefer a container with ice which I can refill periodically. It would be safer and heavier.
You can carry more coldness in phase change materials than in the cooling potential of some battery powered mechanism.
Yes, that’s what sweating is.
Pelieter barely even works. It “works” to the level you can record a temperature change but that’s it. Completely useless and power hungry in nearly all applications.
I think this is probably the best way to go. That is, increasing airflow along the skin. Any more active cooling system is going to add a lot of extra bulk and / or weight, and humans are already about as good at getting rid of excess body heat as it gets, through perspiration. Just allowing the natural cooling system to do its job is probably going to work better than something you can carry around.
Humans have been carrying loads on their backs for more millenia that we can count.
This is a solution for people who don’t actually carry stuff often.
Toughen up is the real answer.
haha i would use tough to criticize this from a totally different direction…i carry stuff on my back all the time and i’m good at it and strong but heat wears me out in several different ways, some of which i don’t think i would be able to adjust to no matter how much i work
but i think this frame doesn’t seem tough to me. i suspect i would destroy it in a week at the most, given the way i use my backpacks. it’s a hard engineering problem, no matter whether you think it’s worthwhile or not.
We also invented shoes. And backpacks.
It’s indicative of the future. However, it won’t help when the environment reaches Wet Bulb temperatures as airflow and sweating doesn’t cool you.
Then, as implied by the comment above on Neil Stephenson’s excellent book Termination Shock, one needs an EarthSuit , a battery-powered, actively-cooled garment.