Greetings /diy/
It is I, that Autist with the cooling vest.
Honestly this is barely worth starting a new thread, but I wanted some input from you guys.
Since last thread I have replaced my home made wrist and elbow seals with some cheap Chinese silicone drysuit seals. I now have a workable vacuum seal on the gauntlet.
Next step is figuring out how to mount the heatsink and pressure gauge through the PVC pipe while maintaining a good seal.
I haven't done anything like this before so I've got a few ideas for you guys to tear apart before I waste time and materials testing them.
A quick run down for those not familiar with my project, the aim is to create a highly portable medical device which will dynamically manage a person's core body temperature when climate, required PPE/activity, and/or medical conditions would have resulted in hyperthermia/heatstroke.
It achieves this using a peltier cooler applied to a heatsink in direct contact with the skin, along with a partial vaccum chamber to prevent local vasoconstriction under the heatsink.
>>994315
>>994315
2
>>994315
3
>>994315
4
>>994315
5
>>994315
You know what would work way better than this retarded venture? A small box you stick someone in that has a controlled temperature system you stupid fuck.
A box has no flex seals, less of a chance to leak, fits multiple sizes of humans, is much cheaper, and has an easier to control environment.
That heat sink you have on their is retarded.
Kill yourself.
>pic related, a box already invented that does this exact thing you want to do
>>994321
>>994320
>>994319
>>994318
>>994316
>All I can think of while looking at these drawings is pic related...
>>994335
The heatsink is not the final design obviously.
Oh yeah and I totally see no advantage to having a ~1-2kg self contained wearable cooling device over stuffing a person into a refrigerator.
That's why DARPA is offering grants for the development of wearable cooling systems for soldiers in the field and ARPA-E has funded the DELTA project to the tune of $60 million.
I'm sure once you tell them your idea about stuffing people into refrigerators they will award you the full $60 million.
>>994344
A box is more durable, can be folded, and made cheaper and more portable than your mystery suit.
Good luck designing a 60 million dollar fridge suit in your sanic blueprints.
If you needed to medically cool someone a cooled blood replacement or box is the best option to supercool a body in a brain injury event. Which they already so by the way.
>>994344
>ONE TO TWO KILGRAM COOLING SUIT
Good fucking luck. No way in hell are you going to have a four pound suit like that without literal marvel comic tier magic metals and materials.
The cooling unit alone would weigh triple that EASILY if not much morw.
Maybe if you had a viable exo suit to hold the weight bit otherwise it's completely useless.
Humans have a cooling system built in already. It's called sweat.
Never really followed the threads in detail, but I've always liked your drawings. Keep going for it, anon.
>>994388
>2009
>from 180 to 620 pull ups
>better than steroids and legal
>our commercial version is coming out soon
>2016 has rolled on by still nothing out
Yeah must be a miracle device for it to not be out 7 years later.
>>994386
Most of the elements of what I'm building have been done before, but they've never been put together in quite the way I intend to use them.
There are devices with the same function that are larger and use different cooling mechanisms, and there are devices with a different function that use a similar cooling mechanism.
The Stanford magic cooling glove is probably the closest in terms of form and function, but it uses refrigerated water (requiring a separate cooling unit) and prevents the use of the hand you wear it on.
'Wristify' uses the same peltier technology and is the size of a wrist watch, but seeks only to give the perception of cold, rather than attempting to affect the core body temperature.
DARPA has a compressor based backpack personal cooling system that I believe weighs in at under six kg, including batteries and can last for up to 12 hours, but it uses one off custom parts and would be nigh impossible to /diy/.
Cooling suits (or vests) used by astronauts and race car drivers use recirculating refrigerated water, and while they're much bulkier than my system will be, they are still lighter than installing an A/C system in the car.
I believe there is also a design someone had for a shoe that pumped chilled water through a custom insole, but they were the size of ski boots and only functioned when they were on top of a floormat that powered them inductively.
Ice vests achieve much the same goal as my device, but much less precisely. They often cool too much and the amount of cooling applied cannot be controlled.
Phase change material PCM vests seek to solve the problem of overcooling by use of exotic materials that melt at the temperature you want the vest to maintain. Once again though, the cooling effect cannot be dynamically controlled.
If anyone can find something more similar to what I'm attempting I would love to do some reverse-engineering, but so far I'm coming up with nothing.
>>994390
That's because no one really gives a shit about it. It is only useful in medical situations for heat stroke. There's a version of it for hypothermia too used by the military and underwater welders.
That's also not a miracle, even slightly.
>>994362
Actually the most common cooling technique we use in the ICU is a cooling mat which the patient lays on, not a 'box'. If you weren't such a fucking retard you would understand why putting a patient in a fucking box to cool them down is a stupid way to go about it.
Shedding excess heat is one of the things the human body is best at. It's one of the reasons we were successful persistence hunters during the early paleolithic, and one of the reasons we're hairless beasts to begin with.
There's nothing you're going to carry around on your body that is going to dramatically enhance your capacity to cool down compared to the metabolic effort of carrying around a bunch of fucking heavy gear.
The only reason to engineer a cooling suit is when you're forced to wear a heavy suit to begin with, like when people are firing bullets at you, or you need to resist the vacuum of space.
A cooling suit for cooling's own sake is a retarded idea. Read up on the physiology of thermoregulation, and you'll see what kind of adaptations your body already has. You're up against millions of years of evolution driven by life-or death selective pressure.
I hate to be a downer on a real DIY project, but there's 1000 better things you can do with your time and money.
Lrn 2 CAD scrub
>>994466
I understand the physiology of thermo regulation, my device is based around exploiting how this works.
First: There are people with medical conditions that cannot regulate their own body temperature. The simplest example of this is people with certain types of paraplegia. Due to their injury their bodies do not respond to appropriatly to hyperthermia as yours would, by increasing perspiration and surface perfusion, and so they must wear cooling vests, or avoid going out in hot weather entirely.
Second: This is not a suit, the aim is to cool the whole body with just the gauntlet. This is the advantage of my device over a cooling vest, and the reason a partial vacuum is required to increase skin perfusion. The total weight of the device will be less than 2kg. Granted it's not going to increase your endurance, it's going to be severely limited by its power supply, likely to 2-3 hours running time while it's fully self contained.
Third: Yes there are way better things to do with my time, but this is a personal project. I don't expect to make money off this. I'll be very happy if I manage to build a working prototype.
I'm not American so I'm not eligible for any of those grants anyway.
>>994482
These are just some quick sketches I drew at work. I work in a hospital. They don't spring for CAD software on the computers.
Obviously they're not to scale, but they should be enough to see what I'm getting at.
>wear bodysuit (i.e. something like latex but not latex)
>attach gas canisters to back
>one canister regular air, other cold stuff i.e. nitrogen
>valves
>trade air ballast-style
>apply thermistors
>automate, PIDs everywhere
That's what I'd do.
>>994688
There are significant problems with this idea.
>>994501
>Due to their injury their bodies do not respond to appropriatly to hyperthermia as yours would, by increasing perspiration and surface perfusion
Wouldn't that mean you wouldn't have to use the this trick to do it with them as their body already would not vasoconstrict to the cold gauntlet?
>>994709
Unfortunately no. The response that causes local vasoconstriction can operate independently to the body's autonomic response to core temperature.
So nobody has any ideas for how to mount a pressure gauge on a PVC pipe?
>>994321
might be worth while to look into thermo-electric coolers. i am unsure if you would have to use solar or battery power or how that would work but just a suggestion.
>>995602
It already uses a thermo electric cooler. TEC= peltier element.
>>994315
You are a complete fucking idiot, 1) you dont understand the rules of thermodynamixs 2) you are an autist and C) you should kil yourself
>>995982
Please explain where my understanding of thermodynamics is incorrect?
>>994315
>Next step is figuring out how to mount the heatsink and pressure gauge through the PVC pipe while maintaining a good seal.
Two
Part
Epoxy
I recommend JB Weld or DP or Scotch Weld
If you don't want to fix your pressure gauge on directly, drill a hole and epoxy a tube w/ threads in instead
>>994453
So then make a cooling snuggie instead. They also have heated blankets.
>>996159
The point of this devices is to be more mobile. If you're just going to be sitting in the couch, buy an air conditioner.
Cooling vests (recirculating type) and body suits already exist and operate on a similar principle to the cooling mat.
They are expensive, cumbersome, and require an external refrigeration pack.
I drew up some concepts for a /diy/ circulating cooling vest a couple threads ago, but it's not as simple as you might think, especially with regards to the construction of the vest itself. You can't just wrap yourself in aquarium tubing and call it a day, you need to tubes that are flexible enough to conform to your body in order to give good area of contact, but at the same time not allow themseves to kink, or water to pool in the bottom of the vest.
This isn't a problem with a cooling mat, since the patient lays on top of it and the water only flows horizontally. In a vest you need a well fitted, (elasticised?) outer layer to help the tubes keep their shape, an inner layer to manage perspiration and condensation, and a backpack to hold the refrigeration components and reservoir.
Is it doable? Absolutely, but it's not what I'm trying to build at the moment and it requires some sewing skills which I don't currently have. The refrigeration components are also going to be very expensive.
>>994315
>Greetings /diy/
>It is I, that Autist with the cooling vest.
(I did not see the other thread/s)
First off,,, the main problem with using Peltiers is the relatively large amount of current that they draw.
Second off, a wrist unit is a waste of time. My own invention, the Chill Breather©©, is infinitely more sensible and the only true solution.
[pic related]
The Chill Breather©© is a small box with Peltier units built into the "roof". The hot side is exposed on the top and the cold side is inside.
The box has a intake vent on one end, and an insulated hose+mouthpiece on the other end, and one-way flow valves on the hose. As you breath normally, air is drawn through the running box and cooled before you inhale it.
(the dripping water is condensation--another reason the Peltiers need to be mounted on the roof--so the water from condensation runs down the cold-side heat-sinks and drips off elsewhere)
The reason for this is simple: to benefit from any sort of air-conditioning, you have to expose as much of your body to as much air as possible, so that your body can lose heat to the cooler air.
The interior of your lungs has WAY more surface area than the whole exterior of your body, and the membranes inside your lungs are way thinner than your exterior skin.
The heat transfer will be far more effective inside your lungs than anywhere (everywhere!) else.
The Chill Breather©© -- so awesome I patented it twice.
>>996185
The current design calls for a 60W peltier to provide ~20-30W of cooling. This will put a heat load of about 90W on the external heatsink.
According to some rough estimates, a person at rest puts out about 100W of heat (based on estimates used to calculate air conditioning loads).
Testing will be nece
>>996196
*cont.
Needed to see if 30W of cooling us sufficient, but I'm working under the assumption that it will be.
If the device is running at full power then it will require at least 60Wh of battery capacity per hour (obviously), but my working theory is that it won't need to be running on full blast 100% of the time (since it controls it's output dynamically to maintain a core temperature range).
Are there issues with my idea? Maybe, but these are issues that require testing, not abandoning the project. And yes, I am aware this may not end up working, but that's a chance I'm willing to take.
The idea with the air cooler is interesting, I wonder if anyone has tried something like that before?
>>996185
One of the components I hope will help my efficiency is that I'm not cooling air at all. I've got the cold heatsink in direct contact with the skin (possibly with some thermal gel) which should (in theory) result a more efficient heat transfer (conduction rather than convection) and help to make up for the efficiency loss of using a peltier over a compressor type cooler.
In environments that are colder than body temp, the heatsink may provide some level of cooling with the peltier off and just the fans running. (requires testing).
Op I like you.
>>994344
>for soldiers in the field
>for Generals outside ac huts
ftfy
this shit is a retarded pipe dream. no soldier will have a substantial change in gear for another 15 years
>>998557
DESU I'm mostly aiming at medical applications, the military is just a good source of funding and existing research. They invest tons of money on retarded pipe dreams all the time.
>>994466
As someone who lives in a temperate rain forest where it is currently 100F 89% humidity right now, i can attest that you simply can't sweat to remain cool.
I'm currently sitting at my PC desk with my feet in buckets of cold water that gets changed every 30-45 mins or so, a wet dishrag wrapped around my head, and a box fan blowing across me on high. That still doesn't cool me down enough half the time. I'm holding off from firing up my AC since it makes my feel worse when I have to go outside to work.
A cooling suit would be amazing.
This is a "good on paper" idea.
Whats your power requirements? Solar wont be nearly enough. Battery will add lots of weight. Figure out the volt and amp requirements.
Personally I would scrap the Peltier part of it. A sleeve with a sealed loop tube of coolant running through it and the heat sink would be better.
Tube + sleeve = more surface area contact. Small DC motor as a pump + 9v battery = Lower power bill.
Heat sink #######
tube ======
Sleeve ------------
tube ======
Skin MMMMM
>>998698
So .... Similar to watercooling on a PC?
With any tube/sleeve design you would lose the bodys natural cooling ability. Zero air flow over the skin means zero natural heatloss, making your job ALOT harder.
>>998698
Power requirements are estimated to be about 60w at max output... Which is a lot.
The current design calls for ten 18650 batteries, which weigh about 500g with holders, and provide a combined ~100Wh of power. This gives a theoretical run time of about 1.5 hours.
My working theory is that it won't need to run at max output 100% of the time so I'll see how that goes.
If I need more power then I may have to resort to a belt back.
>>998698
Also, this only works if the environment temperature is less than 37C, otherwise, without a peltier, you'll just be heating them up.
>>994335
It's not for hospital patients you fucking idiot, it's for shit like HAZMAT work in full gear on a hot day.
>>994380
>The cooling unit alone will weigh triple that
OP is using a single peltier element. They weigh about 20 grams.
This reminds me of the hydranus thread.
Seems like it would be a lot more cost effective and pleasant to just drink ice water.
>>998894
Maybe it's the same guy
ayy it's you again
keep up the good work
>>994315
I believe in you op. this could have actual medical uses. fuck the trolls /sjw
I really love how angry people get at this guy, on the board /diy/ someone tries to invent something weird.
And half of everyone goes on a crusade condemning him, attacking his character or just hating in general, I guess /diy/ isn't much better than /b/ when it comes down to it,
Anyway, best of luck with the cooling vest OP. I hope you don't let these /diy/ rats get to you
>>994315
Why do you need the vacuum?
Also, didn't you consider the whole "flexible tubing embedded in textile, going to passive heat sink, powered by battery" thing? What made you discard it for this?
Keep it up, DIY is good for you, regardless of what you make, really.
>>999253
The vacuum is needed to increase skin perfusion. Otherwise you'll just end up with a wrist that's painfully cold and numb without lowering your core temperature.
>>999185
I like the fact that the default assumption is that any OP is a mouth breathing retard, see in most places (like kickstarter) people assume that a person saying sciency things knows what they're talking about.
>>999253
The cooling suit idea was something I drew up some concepts for but it's not something I'm actively developing. You can buy systems that do pretty much what the cooling suit was designed to do. It just seems like a more difficult and less interesting project that the cooling gauntlet which, if it works, will actually be pretty innovative.
>>994335
>Their
>>999185
imo diy is bigger cancer than b, people go full raging autist on here if you don't do things their way.
>>994315
>>999486
>>999185
>>999173
>>999157
>>998698
>>996185
Went through the archives to find the cooling vest saga:
https://warosu.org/diy/thread/S947885 (cooling vest thread; the autism begins)
https://warosu.org/diy/thread/S962807 (peltier gauntlet thread; OP goes sanic)
https://warosu.org/diy/thread/S992720 (Cooling vest guy appears in diy A/C thead)
https://warosu.org/diy/thread/S994315 (this thread)
Limited medical knowledge here, but isn't the issue with overheating that the brain gets too hot? Why not have a belt pack with batteries and heatsink and peltier devices on it, and then run a tube of coolant to the neck to wick heat out of the blood going to the brain?
If a vacuum is needed, it would be easy to put a small pressure lock vacuum fitting on the neck in a small 1" x 1" area on both sides and hold the vacuum to the neck with a strap.
Alternately, instead of the arms, go for the thighs. Large veins and arteries there, easier to conceal, and you don't have to wrap the whole leg in PVC and vacuum seal it.
Just a small like 2" x 6" skin tight, mild vacuum chamber over the large blood vessels in the upper right leg, held on with a moisture wicking tensile cloth and the coolant pumped up to the belt pack.
Either you would be targeting the most crucial location or the location that can make the greatest difference, right?
>>1000067
The main reason I'm using the forearm is because it's easier to set up the vacuum chamber there, and for comfort. Your upper leg changes shape quite substantially when you bend your leg, and the rigid vacuum chamber would be uncomfortable to sit on.
The neck is a good choice for blood flow, but neck seals are uncomfortable, and the fit would be awkward, since it needs to be rigid.
When you're cooling the skin heat is lost mostly from capillaries, that means the cooled blood is on its way back to the heart, so it doesn't really matter where you remove the heat, it all lowers the core body temperature.
>>1000067
Oh, you mean like a vacuum cup? I haven't really looked into that too much, but based on what I've seen with negative pressure dressings (KCI makes them for wound healing) you need to have a pump attached to maintain the vacuum. With the cooling device you would need a ridgid chamber under the dressing and with rigid edges pressing into the skin I would be concerned about causing injury after some time.
It's something to look into, but it's pretty complicated.
>>1000155
>so it doesn't really matter where you remove the heat, it all lowers the core body temperature.
There are some places on the body that are better than others for cooling down. I remember an experiment with 2 guys out in the snow. 1 had a coat and pants on, no gloves, hat or boots. The other guy only had those 3 on.
And the coat pants guy lost his temperature faster. Your statement is correct tho. Cooling the body anywhere will help with the core temperature. But not taking advantage of the best areas seems like a big fat mistake
>>1000184
The forearm is a pretty good place, admittedly it is a compromise since there are other areas with better skin perfusion, but I wanted the hands to be free, making a rigid-yet-comfortable shoe is difficult, and other body parts are more difficult to enclose in a vacuum chamber.
The use of the vacuum kinda cheats a bit here, since it negates what is normally the downside of cooling a more peripheral area, vasoconstriction.
>>1000188
Maybe armpits?
>>994390
>>994390
uhh.. you can buy this...
http://www.avacore.com/
or make your own with about $100 of off the shelf parts. I did it and it works pretty good.
http://www.instructables.com/id/CoreControl-DIY/
I live in the south and its really nice for working outside in the summer. After a couple of hours I feel like shit. Wear the glove and enjoy a cold drink and in 15 minutes I feel totally refreshed to work some more.
>>1000189
Yes, this is one of the things my idea is based on.
My device however doesn't need the refrigeration pack, doesn't enclose your fingers in a rigid box, weighs 1/5th as much and controls itself dynamically... Or at least it will when I get it to work.
>>1000193
This is what their design looks like (with the refrigeration pack off camera).
>>1000193
>>1000201
And this is what mine will look like.
My cooling gauntlet is designed to be worn continuously and turn itself on when needed, theirs is designed to cool someone down once they're already overheating and are taking a break.
I mean, an obvious (to me anyways) option for the heatsink is the casing itself. you would have to either cover the PVC with a conductive metal or remake it with such a metal but it would cut the need for having a separate large heatsink on it. a metal would also possibly help as a pseudo shield in drastic time during combat?
I'm not a robot
Op, keep at it. Even if it fails you'll at least learn something.
Not to mention that it could be awesome if it works.
>>1000217
The external heatsink will likely be at 50-60C under max load, so I need to insulate the arm from it. There's going to be a layer of silicone rubber under the heatsink to protect the PVC from the heat. The internal and external heatsink also need to be as thermally separate from each other as possible, apart from the point where they meet the peltier element.
If this prototype works, the next one will likely be a more form fitting design made of fibreglass to cut down on weight and bulk.
The external heatsink on the first prototype is probably going to be salvaged from an ond GPU, on the second prototype I've got a friend who can mill something custom that wraps around nicely and I'll 3D print the shroud. Ideally I would use heat pipes to put the heatsink on the top of the gauntlet, but that's a bit more complicated.
Consider Kydex instead of fiberglass. Tough and easy to form. Gun forums have plenty of info as it's popular for holsters.
OP keep doing what you are doing and let us know what the outcome is.
Here is a word of caution though, this thing (if it works as you intended) should NOT be used in environments where ambient temp is higher than than your core temp and have high humidity, since it will likely cause condensation of water in your lung which can resulted in serious and even fetal consequences.
>>1001787
>mfw OP slowly starts shrinking back into a baby, eventually becoming a fetus again
How awful.
>>1001787
Are you sure about that? Your body's natural evaporative cooling will keep your core temperature at 36.5-37.5C even in a sauna, if sitting in a sauna with that temperature difference doesn't cause pulmonary edema, why would my device be any different?
>>1001789
fetal ---> fatal
my bad
>>1001799
https://www.quora.com/What-prevents-the-water-vapour-we-breathe-out-to-condense-into-liquid-water-in-our-lungs
The difference, I think, will be in the prolong and repeated use of your device vs a sauna or for that matter a cooling glove.
What you are making can have enormous benefit in many situations if it actually functions, just not in high humidity and high temperature environments. For that kind environments, a fully sealed air condition suit like the one they use in Naica is a better solution.
>>994315
How are you going to seal it around the the ends of the arm and wrist sufficiently to allow for a vacuum to be created on the inside?
>>1001810
That link doesn't seem to support what you're saying, I mean they physics of what you're saying makes sense (100% humidity + temperature drop = condensation), but physiologically your lungs can absorb small amounts of fluid, that's why we can use nebulisers to administer drugs via the lungs.
I'm not sure of the rate of condensation where there would begin to be problems, but I'm sceptical that there would be any difference between the body cooling itself with evaporative cooling vs. using a cooling device/icepack to cool the body; after all the temperature difference between air/core temp will be the same regardless of how the cooling is applied. If core temp raised itself to match ambient temp you would die, or at least be very ill.
Where did you hear this information if I might ask? If there have been studies I would be very interested to read them - I have corporate access to most medical journals, so pay walls shouldn't be a problem.
>>1001815
I have already solved this; using silicone drysuit seals. It's not a total vacuum obviously, I only need a few millibars.
>>1001819
Unfortunately there is no studies I can find for this, since it is not very particle nor likely human to do this kind studies.
I can only point you to situations like exploration of Naica Crystal Caves as example where facing extreme environment of heat and humidity which can kill a human within 20 minutes of exposure w/o protection scientists devised a 2 part solution where a full body cooling suit combine with a cooling backpack which supplies cooled and dehumidified air to user via a gas mask (both passive, aka. ice cooled) that help explorers extend their exploration time to up to 2 hours.
Now, I agreed with you on both physics and physiology facts you lay out on your response. but I will still caution about using it in said environment as form of long term temp regulation device. The fact that lung tissue can absorb a bit of liquid does not mean that it can handle condensations fro say 4 hour work shift or whatnot.
PS: why the focus on its ability to work in environments with 37C+ temp and high humidity? I don't think we have many places like that out in the nature, nor does majority of the machines used in manufacturing will survive long in that kind environments.
>>1001918
I'm not really focusing on that, like you said there's not many places like that in nature - and if my device was to be used in such a place it could be combined with a respirator.
I'm just curious since I had never heard of this phenomenon before and safety concerns are something that's very relevant to my project. If my device cannot work in such an environment that is something I would want to be aware of.
I was thinking about >>998665 where he says the current temp is 100F 89%RH - it's not inconceivable that one day it might be 110F 95%RH - now would my device be dangerous to use in such a scenario? It's certainly not as extreme as Naica. That's something I would want to know.
>>1001933
I think one of the often negated benefit of personal temp-regulation equipment is that it save a lot energy, especially if it is not passively cooled (aka ice).
In >>9988665 situation a compressor based AC works much better, since it is above ideal storage condition of books and electronics alike, they may still work fine, but their reliability and expected life will definitely cut short, so something that can cool and dehumidify the whole room instead of just one's body is defiantly preferred.
>>1001960
This is mostly what the ARPA-E DELTA project is about. Energy conservation. IMO some of the projects they funded are even more autistic than mine.
any o yall knobs consider the most effective and cheap cooling system we have?
>>994315
Holy shit son, these already exist, there's no need to reinvent the wheel here.
I swear, no-one on /diy/ reads the thread before commenting anymore.
>>1003722
Granted this is an incremental innovation rather than a revolutionary one, but if you've been paying attention (>>994430) you'd know the specific advantages my system will provide over similar systems that exist today.
I've been quite open about the potential challenges and limitations of the project, which are numerous.
You're not the first person to point out that the avacore exists. No shit, half my design is based on their research. >>994388 , >>1000193
>>1003575
Yes. >>998923 , >>994466
>>995982
Motherfucker you can't even spell thermodynamics.
>>1001787
no it won't
>>994447
>porters
>construction
>literally any outside job
>>1003734
Tis because of apps to read 4chan I think. Makes us all lazier than before. And God knows we were lazy before
