How to "power-up" a steel body suit?

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In summary: Enough to build a really beautiful Iron Man-style suit!In summary, Simon is planning to build an Iron Man-style suit for Halloween this year. He has some basic questions about how to power the suit and control it, but he is not worried about the power issue.
  • #1
LaloGarcia91
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So, basically... Since I have my own place/office, tools, machines and everything I need. I've been working on a steel suit just for fun, as a hobby. Based on the Iron Man superhero, and I want it as my Halloween costume this year. My idea is to build it gorgeous, and I'm on that at the moment. It won't be something ugly and cheap, trust me.

So my question is, how can I make it move with me inside? I'm not planning on making it fly, don't worry, that's impossible. But what kind of system/power should I use to turn it on with me inside the suit? I just want to walk, move my arms and torso, lift my knees relatively freely and bend over to grab whatever. And of course, be able to grab a drink.

I already took care of the rest, like how to rotate my hand/wrist, the basic mechanics and stuff.. that's to basic. So what do you think? I was thinking on hydraulic systems, using the back and the front of the suit to hide and cover it. Or perhaps a small hybrid engine? I have no knowledge on that, I read a couple of things though.

The suit as a whole, might weight around 200-250 lbs of steel. I just need to power-up the suit.
Thanks.
 
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  • #3
Simon Bridge said:
Investigate "powered exoskeleton". It is a tricky engineering challenge even if all you want to do is compensate for the weight of the suit.
eg. http://spectrum.ieee.org/video/robo...-batterypowered-exoskeletons-on-real-soldiers
Thanks Simon, I just took a look to the link you posted and seems pretty interesting. Although, seems that's nearly impossible to build for myself alone, this researchers took over 3 years straight to develop this "exoskeleton" to compensate the average weight of a single person with clothes on. I don't think this "exoskeleton" can power up this suit in any means.. I only need the energy/power to be able to lift my arms inside, walk freely, bend over and sit down.. Something "big" or "small" enough to be hidden on the back of the suit and/or the chest. I have no knowledge on that area.
 
  • #4
I don't think the issue is about powering the suit, but about controlling it. And that's no simple matter. That's probably the main reason it took the researchers 3 years to get as far as they did, though I admit that mostly a guess on my end.
 
  • #5
Exactly, powering the suit is not the issue - it's getting the fine control to work properly - meaning smoothly or at all.
 
  • #6
Simon Bridge said:
Exactly, powering the suit is not the issue - it's getting the fine control to work properly - meaning smoothly or at all.
Drakkith said:
I don't think the issue is about powering the suit, but about controlling it. And that's no simple matter. That's probably the main reason it took the researchers 3 years to get as far as they did, though I admit that mostly a guess on my end.
So, basically.. There's nothing I could use to achieve the goal desired? Since I don't have much knowledge in engines, I don't have nothing but clues such as a actuators, servomechanisms, hybrid engine, hydraulic system and now, exosuit, or maybe a combination of any of those. Perhaps a type of homemade exosuit. Suficient to make me move inside the suit. Not planning on anything else but that.I'll be the soul of the party if I get this done! And maybe I could even assist to the comi-con convention. I'm really into this suit, I just need knowledge I'm lacking at the moment.
 
  • #7
You can ask again, but the answer is unlikely to change. The issue is not power, but control.
 
  • #8
Vanadium 50 said:
You can ask again, but the answer is unlikely to change. The issue is not power, but control.
Thanks for your answer man! Yeah, I think I misused the words. As you say, the real word is "control".. What kind of system or engine or whatever could I use to control the suit easily.
 
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  • #9
LaloGarcia91 said:
I'll be the soul of the party if I get this done! And maybe I could even assist to the comi-con convention. I'm really into this suit, I just need knowledge I'm lacking at the moment.
I'd suggest that you start with a basic unpowered exoskeleton for your first year's project. That simplifies things a lot, will still be fun, and makes it a do-able project for this year's Halloween party (and ComiCon, or whatever). Then, build on that for next year, and add some basic battery powered strength boosting to your second exoskeleton. You can always add cosmetic bits to each exoskeleton, like a helmet and gloves, boots, etc.

Then maybe the next year you will have learned enough to do an Arduino-based or some other intelligent controlled heavier exoskeleton with a heavier covering, or some other fun project. Stay safe and smart! :smile:
 
  • #10
berkeman said:
I'd suggest that you start with a basic unpowered exoskeleton for your first year's project. That simplifies things a lot, will still be fun, and makes it a do-able project for this year's Halloween party (and ComiCon, or whatever). Then, build on that for next year, and add some basic battery powered strength boosting to your second exoskeleton. You can always add cosmetic bits to each exoskeleton, like a helmet and gloves, boots, etc.

Then maybe the next year you will have learned enough to do an Arduino-based or some other intelligent controlled heavier exoskeleton with a heavier covering, or some other fun project. Stay safe and smart! :smile:
Thank you, that pretty much what I was thinking. That's why the suit is on stand by at the moment, I started building the blueprints and building the forearm from cardboard, but I stopped. Since as you're saying, I first need the "engine", in this case seems it'll be an exosuit. After having that, I could start working the suit around it.
 
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  • #11
Nice. Do you have access to a metal welder? That will help you a lot in your work on an exoskeleton. And a sheet metal break and a shear? You might want to take a metal working class at a local community college, if that is a resource near you. :smile:
 
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  • #12
The movements of the human body are very complex. Almost every joint can move freely in two, if not three, dimensions simulateously.

Just think about the shoulder for a moment. It can go out/in, forward/back and rotate - simultaneously. How will you activate those motions, let alone control the feedback on them? Even doing 1 dimension will be tricky. How will you do it in 2 or 3?

What if they don't deactivate flawlessly? I fear you'd dislocate your shoulder!

Not that I want to be a party-pooper. I am a big big fan of outrageously complex costumes. Matter of fact, it's already getting late in the season for startring on this year's Hallowe'en.
 
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  • #13
Is there a reason to make it out of metal? Other than the extreme cool factor? What if you made the prototype shapes, then vacu-formed them out of plastic? It is very important to keep weight to a minimum in such an outfit.
 
  • #14
berkeman said:
Nice. Do you have access to a metal welder? That will help you a lot in your work on an exoskeleton. And a sheet metal break and a shear? You might want to take a metal working class at a local community college, if that is a resource near you. :smile:
Yeah, I have everything mentioned above and a lot more in my office. I have a bit of knowledge with this kind of tools. I own them all, but the welder, I don't own him. And he's really good,.. I was thinking on getting in a local class actually, and I will though. I highly doubt the welder will have any knowledge on exoskeletons though.
 
  • #15
DaveC426913 said:
Not that I want to be a party-pooper. I am a big big fan of outrageously complex costumes. Matter of fact, it's already getting late in the season for startring on this year's Hallowe'en.
[hijack]This means nothing without pictures [/hijack]
 
  • #16
DaveC426913 said:
Is there a reason to make it out of metal? Other than the extreme cool factor? What if you made the prototype shapes, then vacu-formed them out of plastic? It is very important to keep weight to a minimum in such an outfit.
DaveC426913 said:
The movements of the human body are very complex. Almost every joint can move freely in two, if not three, dimensions simulateously.

Just think about the shoulder for a moment. It can go out/in, forward/back and rotate - simultaneously. How will you activate those motions, let alone control the feedback on them? Even doing 1 dimension will be tricky. How will you do it in 2 or 3?

What if they don't deactivate flawlessly? I fear you'd dislocate your shoulder!

Not that I want to be a party-pooper. I am a big big fan of outrageously complex costumes. Matter of fact, it's already getting late in the season for startring on this year's Hallowe'en.
I'm planning on making the mechanics smart enough to prevent any terrible thing to happen such as a shoulder dislocation, fingers and whatever that could injure myself. The good thing is I'm now planning on using the suit for a battle. I want to do ot of metal for the only reason that it is a personal challenge. I started up with cardboard, then I'll work with aluminium and at the end, steel. Not to thick though. I'm also padding the suit all over on the inside, so myself is not in contact with steel, cables and stuff.
 
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  • #17
berkeman said:
[hijack]This means nothing without pictures [/hijack]
Yeah. Pix are long gone.. :(

I made a costume based on a friend's dream. He dreamt that I was Dave - Fireman of the Future. Hip-mounted jetpacks for getting into and out of fires, and a disintegrator pistol (what better way to put out a fire than to disintegrate whatever's burning?) I added a working grappling hook, a belt pack, shoulder lights, and, of course, a bona fide (retired) fireman's helmet (which I still have) with crosshair sights.

Another year I made a dragon suit. (Picture iron man but with teeth, wings and tail control surfaces). The wings actually deployed and retracted. Man, that was fun to work out the hinges going between laying flat on my back to an eight foot span.
 
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  • #18
DaveC426913 said:
Yeah. Pix are long gone.. :(

I made a costume based on a friend's dream. He dreamt that I was Dave - Fireman of the Future. Hip-mounted jetpacks for getting into and out of fires, and a disintegrator pistol (what better way to put out a fire than to disintegrate whatever's burning?) I added a working grappling hook, a belt pack, shoulder lights, and, of course, a bona fide (retired) fireman's helmet (which I still have) with crosshair sights.

Another year I made a dragon suit. (Picture iron man but with teeth, wings and tail control surfaces). The wings actually deployed and retracted. Man, that was fun to work out the hinges going between laying flat on my back to an eight foot span.
Hard to picture that:woot:! What material was it? And how did you managed to control it once inside the suit? I was thinking, and regardless of the suit weight (250 lbs at most), whatever "engine" I use to "control" it once wearing it, it won't be lifting those 250 lbs in any means. Realistically, I just need to be able to walk and lift my arms freely, how much can the whole arm weight? 50 lbs? at most... The force needed to lift the arm or to "flex" my forearm to 90º is minimal, at any point I'll need to lift 250 lbs, that's just the suit as a whole. I was actually even thinking of pulleys! Perhaps a good set of pulleys inside the suit placed on the right place and being as small or as big as needed will make the work, or at least 50% of it. The rest might be handle by anything else, maybe actuators or hydraulic fluid.
 
  • #19
The good thing is I'm now planning on using the suit for a battle. I want to do ot of metal for the only reason that it is a personal challenge. I started up with cardboard, then I'll work with aluminium and at the end, steel. Not to thick though. I'm also padding the suit all over on the inside, so myself is not in contact with steel, cables and stuff.

This becomes quite challenging on several levels quickly. With added padding there is also added thermal load for you. Thus a larger suit with more power to carry around the AC gear also. There is a Canadian experimenter who is obsessed with a suit primarily for grizzly bear research. I would suggest a web search or at least YouTube for Troy Hurtubise. This will give you lots of entertaining insight into a armored suit. Some of his videos are up to 10 years old as he has been at it for a while.

For a first year costume I would go with composite or sheet aluminum to allow movement with your own power. Then progress as possible with more time.
 
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  • #20
Before you get too far ahead of yourself, think about a simpler problem: a glove. How many motors will you need? (You might get an idea by how many muscles there are) How many sensors? How do you plan on limiting motion? It wouldn't do if the glove broke the hand inside it. How many lines of code do you think this will take? How will you debug it without breaking the hand inside it?

This is a much, much simpler problem than what you propose, since you don't have to worry about balance.
 
  • #21
Ketch22 said:
This becomes quite challenging on several levels quickly. With added padding there is also added thermal load for you. Thus a larger suit with more power to carry around the AC gear also. There is a Canadian experimenter who is obsessed with a suit primarily for grizzly bear research. I would suggest a web search or at least YouTube for Troy Hurtubise. This will give you lots of entertaining insight into a armored suit. Some of his videos are up to 10 years old as he has been at it for a while.

For a first year costume I would go with composite or sheet aluminum to allow movement with your own power. Then progress as possible with more time.
Thanks for your answer fella, that idea looks great. Someone above said something similar and as I said before, I'm first building it from cardboard, then aluminum and if everything went well with the aluminum, I'll start working on steel. The good part is that I'm actually building up the instructions for the suit, they doesn't exist, so by the end of the cardboard suit which I already started, but left on stand at the moment because I didn't know what to use as an engine on the end product... It'll take me around 1 month to complete the cardboard suit, since I'm getting the measurements right (not just for me but for anyone else once I finish the suit). I'm building the instructions, I might finish the aluminum suit in 1 week since I'll already have the instructions done. If someone want to build this from titanium it doesn't matter. The instructions will be there already set for anyone. Also, the thermal thing is not really an issue for me, in the worse scenario I'll just take off the suit and rest maybe 10 minutes and then get it on again.

In the meantime, I'll check out that experimenter you're telling me about.
 
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  • #22
Vanadium 50 said:
Before you get too far ahead of yourself, think about a simpler problem: a glove. How many motors will you need? (You might get an idea by how many muscles there are) How many sensors? How do you plan on limiting motion? It wouldn't do if the glove broke the hand inside it. How many lines of code do you think this will take? How will you debug it without breaking the hand inside it?

This is a much, much simpler problem than what you propose, since you don't have to worry about balance.
Thanks! I'm not really planning on using motors in the glove, that will be completely mechanical.. I might use a basic pulley work attached anywhere from the forearm all the way to each finger, it's not that hard to limit finger motions, it's all about building the right pieces and taking care of security to prevent that.. Plus, that area might work with a flexible "tube" of plastic on each finger to give fingers the ability to flex.Something like this, look at the fingers.
maxresdefault.jpg
 
  • #23
LaloGarcia91 said:
Also, the thermal thing is not really an issue for me, in the worse scenario I'll just take off the suit and rest maybe 10 minutes and then get it on again.
Oh no you won't! :wink: I guarantee the suit will take an hour or more to get on and get wired up (every motion sensor has to be calibrated as you assemble), and 20 minutes to take off again.

If you're only half way through the donning process when you start to overheat, you have a suit that can't be donned.
 
  • #24
DaveC426913 said:
Oh no you won't! :wink: I guarantee the suit will take an hour or more to get on and get wired up (every motion sensor has to be calibrated as you assemble), and 20 minutes to take off again.

If you're only half way through the donning process when you start to overheat, you have a suit that can't be donned.
oh!.. Well.. the padding won't be to thick, just enough to keep the wires and steel away from touching my skin. I just want to feel it smooth on the inside and not a bunch of wires and metal, plus I don't want to get pinch. I'm still investigating on what to you for the basic movements. And I thing I'll get into retractable cables, pulleys and gears. I believe I don't need any kind of engine to make basic movements with the suit on.. Also, I'll build it on a way I could get it on and off easily.
 
  • #25
I guess what I'm trying to figure out is how you will activate motion. Presumably, every possible freedom of motion will have a counterpart pressure pad in the right place.

For example, lifting your forearm will press against a pad on the inside of the armour, activating the suit to lift its own arm. Those pressure pads will have to be carefully calibrated with your own body. You'll have a heckuva time getting them to trigger consistently.

I suspect what will hapoen is you'll have to have a flexible, form-fitting inner skin, with all the pressure pads calibrated, and then you will don the hard suit over that, and plug in a bunch of ribbon cables to the actual motors.
 
  • #26
DaveC426913 said:
I guess what I'm trying to figure out is how you will activate motion. Presumably, every possible freedom of motion will have a counterpart pressure pad in the right place.

For example, lifting your forearm will press against a pad on the inside of the armour, activating the suit to lift its own arm. Those pressure pads will have to be carefully calibrated with your own body. You'll have a heckuva time getting them to trigger consistently.

I suspect what will hapoen is you'll have to have a flexible, form-fitting inner skin, with all the pressure pads calibrated, and then you will don the hard suit over that, and plug in a bunch of ribbon cables to the actual motors.

That's pretty much what I'm trying to do (in a way). The main idea is to make everything or at least almost everything without any kind of "powered" engine, I mean, I'm trying to use as much basic physics as possible to get the suit into motion once wearing it.

For example, imagine a rewind spring at shoulder level going all the way down, passing by a pulley at my "funny-bone" level and keep going until it's attached to the wrist structure of the suit. The pulley and the rewind spring will be of course welded to the suit structure. So, every time I lift my forearm; the wire rope will be constantly rewinding up to the shoulder, making the forearm easier to lift. I can repeat this whole mechanism in the other side of the same arm. Having 2 pulleys and 2 rewind springs working in just 1 forearm.

And maybe, after using basic physics as much as possible I could now get into actuators, servos and pistons to do the rest of the work, which won't be that much since the retracting wire rope will have done around 70% of the work to lift the forearm.

Ex: http://www.vulcanexpress.com/vr1433-40/

Or something like this, which has a average load capacity of 15 lbs... And it goes up to 40 lbs of constant force: http://www.vulcanexpress.com/sl31u70/
 
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  • #27
LaloGarcia91 said:
That's pretty much what I'm trying to do (in a way). The main idea is to make everything or at least almost everything without any kind of "powered" engine, I mean, I'm trying to use as much basic physics as possible to get the suit into motion once wearing it.

For example, imagine a rewind spring at shoulder level going all the way down, passing by a pulley at my "funny-bone" level and keep going until it's attached to the wrist structure of the suit. The pulley and the rewind spring will be of course welded to the suit structure. So, every time I lift my forearm; the wire rope will be constantly rewinding up to the shoulder, making the forearm easier to lift. I can repeat this whole mechanism in the other side of the same arm. Having 2 pulleys and 2 rewind springs working in just 1 forearm.
I assume you mean one pulley for flexion (closing the elbow) and one for extension (opening the elbow)?

The two opposing forces of the rewind pulleys cancel in a neutral position, as you continue in either direction the opposing spring force increases and the spring force of the pulley that's supposed to be helping you is decreasing. The net effect is that you're weaker throughout your entire motion range.

Even if you devise some better way of storing the energy The Law of Conservation of Energy means your arm mechanism will always be weaker than without the suit at all. there are losses in all mechanical devices (mainly friction) so your muscle force must make up the difference and the net result is your arm cannot apply as much force as it could without the device at all.
The other problem is that many antagonistic muscle pairs are not balanced force wise which makes any flexion-extension energy storage inherently unbalanced - eg our fingers have evolved with much higher force in flexion (gripping) rather than extension (releasing), for obvious reasons. The difference is around a factor of 4 to 5 so the greatest increase in grip strength would be 20-25%, before losses, this would require you to apply the maximum force during extension which would be uncomfortable to say the least, dexterity would suffer greatly too.

Long story short, if you want to "power up" like your title says, you'll need a power source.
 
  • #28
I hope this isn't a hijack as what I wish to do is to point out just how big (DARPA Big) the control problem is. I'm a paraplegic (T12-L1 burst) with some use of my quads so I can actually move my legs a surprising amount- for a paraplegic. Because I have no proprioception, I am not aware of how my lower body is located in space, or how my legs and feet are moving. Walking is impossible. Standing still is OK, as long as I have a solid support.
Control is not just hardware and power. You need feedback to maintain stability, and I think that feedback control problem is challenging many many teams around the world. From what I've seen, Boston Dynamics is showing very sophisticated stuff indeed, but even their systems are still way too risky to trust with your life.
 
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  • #29
billy_joule said:
I assume you mean one pulley for flexion (closing the elbow) and one for extension (opening the elbow)?

The two opposing forces of the rewind pulleys cancel in a neutral position, as you continue in either direction the opposing spring force increases and the spring force of the pulley that's supposed to be helping you is decreasing. The net effect is that you're weaker throughout your entire motion range.

Even if you devise some better way of storing the energy The Law of Conservation of Energy means your arm mechanism will always be weaker than without the suit at all. there are losses in all mechanical devices (mainly friction) so your muscle force must make up the difference and the net result is your arm cannot apply as much force as it could without the device at all.
The other problem is that many antagonistic muscle pairs are not balanced force wise which makes any flexion-extension energy storage inherently unbalanced - eg our fingers have evolved with much higher force in flexion (gripping) rather than extension (releasing), for obvious reasons. The difference is around a factor of 4 to 5 so the greatest increase in grip strength would be 20-25%, before losses, this would require you to apply the maximum force during extension which would be uncomfortable to say the least, dexterity would suffer greatly too.

Long story short, if you want to "power up" like your title says, you'll need a power source.

Thanks for your answer man, I was actually thinking only in using the pulley mechanism on flexion, not extension. Once I flex the forearm I will let gravity do its work for the extension. I'm assuming I will lift my arm and extend it freely, depending on how strong the rewind wire rope is of course.. I've never done this before, it is a personal challenge, so I have no idea how it will go. Building the suit is easy, the hard part is to be able to move inside the suit freely.

Maybe I used the wrong title, maybe not. What I'm looking is to move freely inside it. No matter how or what I use, perhaps a hybrid engine, or actuators hidden on the back of the suit structure on the inside of course, not the exterior.

And the hand is not really an issue ,I belive. The glove of the suit won't be an issue.
 
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  • #30
Iain53 said:
I hope this isn't a hijack as what I wish to do is to point out just how big (DARPA Big) the control problem is. I'm a paraplegic (T12-L1 burst) with some use of my quads so I can actually move my legs a surprising amount- for a paraplegic. Because I have no proprioception, I am not aware of how my lower body is located in space, or how my legs and feet are moving. Walking is impossible. Standing still is OK, as long as I have a solid support.
Control is not just hardware and power. You need feedback to maintain stability, and I think that feedback control problem is challenging many many teams around the world. From what I've seen, Boston Dynamics is showing very sophisticated stuff indeed, but even their systems are still way too risky to trust with your life.
Thanks! And it's not a hijack at all.. I know that the control problem is really a problem, since that something I'm seeking to fix onthe suit. I'll investigate about that Dynamic stuff you're talking about, I might study the mechanisms. I've been putting a lot of time and effort to this project I want to do since 2 weeks ago, day after day, investigating and reading hours and hours.. Everything helps, literally speaking.
 
  • #31
LaloGarcia91 said:
Thanks for your answer man, I was actually thinking only in using the pulley mechanism on flexion, not extension. Once I flex the forearm I will let gravity do its work for the extension. I'm assuming I will lift my arm and extend it freely, depending on how strong the rewind wire rope is of course..
The force of gravity on your arm is a small fraction of the force the arm is capable of.
Lift your arm with an empty hand, what fraction of your total strength does that require? - the muscle force required to do that is the max force your scheme could provide. It's pitiful, you would barely notice it when lifting anything significant. Once you add in the weight of the unit and losses you'll be better off without it.
 
  • #32
billy_joule said:
The force of gravity on your arm is a small fraction of the force the arm is capable of.
Lift your arm with an empty hand, what fraction of your total strength does that require? - the muscle force required to do that is the max force your scheme could provide. It's pitiful, you would barely notice it when lifting anything significant. Once you add in the weight of the unit and losses you'll be better off without it.
You are probably right on that. Best to make the suit as light as possible to begin with.

If the fabricator ( the OP LaloGarcia91 ) is considering a model similar to a garage door, or truck door, which can be 300 pounds or so, but with a torsional spring assist, one can open and close the door with one hand, as opposed to not being able to open the door at all with no spring assist. Balancing the spring coiling for optimization of the pre-set of the spring force, but with some trial and error one can have the force to be maximum at when the door is closed, fully open or somewhere in between.

But just look at the coil of spring used for this - 6 feet of 1/4 inch wound around a 3-inch radius, approx. 30 pounds of spring for a 300 pound door, with some additional hardware and cable.
If for the suit, the arm weighs 10 pounds one can possibly model the dimensions with a scaled sized spring ( ratio 10/300 ) - not sure how that is going to give the correct spring size, as the number of turns that the spring makes for the movement would be more of a determining factor for F=kx. Add in the friction of the cable through the guides, the extra bulk of the spring and cabling guides and the complexity, and for some reason I feel about 3 to 4 pounds would be added to the suit for spring assist.

Then we have the shoulder, the torso, legs, etc.

I wish to be proven wrong on that, but if "powering up" adds another 30% of hardware to the suit, the 200 pound initial weight quickly becomes 300 pounds by picking off the shelf hardware.
 
  • #33
I've often thought it might be possible using a Stirling engine. This way you could just burn wood and other materials you find as you go to power it. I doubt you could build one that would lift that much steel though.
 
  • #34
I would start with several historical and operational suits of plate armor. That's for showing mobility and armor coverage. Obviously unpowered, and uses the human body for skeletal support rather than supporting itself. Then look at the several version of powered assist technologies being done by various companies. Finally, I'd look into the several good iterations of robots, such as Honda's, Asimo; and Boston Dynamic's, Atlas.

I have a suspicion that any powered body suit that's going to run for a long enough period of time to be useful is going to entail a miniaturized internal combustion engine strapped to your back with either a micro generator or hydraulic pump. Batteries just don't last long enough to be useful, and the U.S. government frowns on private use of nuclear power.
 
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  • #35
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