Creating a Working Prototype of Armor to Move with You

[drag]

btw, I appologize for being rude , better later than never -
Welcome to PF Multiades !

 

[Multiades]

O.K. So what Kind of features would such a system have ?
I assume you could lift very heavy weights, though controlling
your center of weight during such an act would probably be quite
difficult. Running & jumping a lot better (if them soft problems are
solved too). Breaking things. What else ?

I would consider the advantages of the suit to be the natural by-products of its design rather than "features", but that's just semantics.

Some are very obvious -- the fictional system envisioned by R.A.H. in Starship Troopers worked on a very simple reverse-feedback principle. The actuators move when the wearer moves against the inside of the suit; whatever way the wearer tries to move against the suit, it "moves out of the way" of the path of the wearer's limb, and so duplicates his motion.

What does this accomplish?

*There is zero learning curve; you just wear it and it works. Sure, some of the more sensitive tasks would take a little practice, but basic movement should be immediate. There is no control interface to learn.

*The suit completely isolates the wearer from external loads (aside from gravity and inertia). Lifting a 20lb barbell takes zero effort; similarly lifting a 200lb person takes zero effort -- in fact both loads would feel the same unless the control system was designed to offer resistance.

Balance would be relatively hard to get right, but I don't envision needing gyroscopes or artificially-supplied balance. With a properly sensitive control system, the wearer could balance him or herself either immediately or with a little practice.

Jumping... you would almost certainly be able to jump higher, but there is some question about landing safely when coming down from a height. Would you be able to jump higher than you could tolerate on landing? Probably not. If you hop down from a 20' ledge, your technique could be the difference between a smooth landing and a concussion -- but a properly designed frame should almost completely prevent the possibility of broken bones.

Also, some of this concerns the way that the wearer is "strapped in" which could be done many different ways. I figure the more firmly affixed the better. Can you imagine what would happen if the user was able to wriggle around to oppose one of the joints (like the elbow)?

btw, I appologize for being rude , better later than never -
Welcome to PF Multiades !

Thanks! Rude? Hardly -- unless you deleted a post that I never saw.

-Chris

 

[drag]

I would consider the advantages of the suit to be the natural by-products of its design rather than "features", but that's just semantics.

O.K. but like you hinted that's "a bit" not the engineering approach.
Or as a favourite fictional figure with pointed ears, I like quoting, would say:
"Illogical".

It will be too costly and sophisticated for construction works, factories
don't need such complications either, military uses are limmited by
service life and in short urban engagements it would likely be
uncomfortable due to size and speed limitations. Maybe rescue
operations for collapsed buildings or for firemen ?

Live long and prosper.

 

[Multiades]

O.K. but like you hinted that's "a bit" not the engineering approach.
Or as a favourite fictional figure with pointed ears, I like quoting, would say:
"Illogical".

It will be too costly and sophisticated for construction works, factories
don't need such complications either, military uses are limmited by
service life and in short urban engagements it would likely be
uncomfortable due to size and speed limitations. Maybe rescue
operations for collapsed buildings or for firemen ?

Live long and prosper.

I don't want to talk about service life, limitations, and "too costly and sophisticated" until they have been built and determined as such. I believe that has been said about more than one invention that is in widespread and practical use today.

Cheers,
-Chris

 

[zesban]

You know, power armor would be sweet!

Anyway, first post, but this topic has been great to review. A lot of you have some really great resource links.

I noticed someone mentioned construction material. Check out the following:

http://www.liquidmetal.com

Twice as strong as steel, lighter, cheaper to make, better memory, more resistant to thermal expansion and corrosion, and has a cast strength that makes steel manufacturers weep. (Strong steel usually has to be forged.)

Very cool stuff.

As for power, what about an RTG that also reuses heat generated by operation to increase power efficiency? Oh, and carbonfiber nano tubes as artficial muscles used to assist movement instead of mechanical drive mechanisms. Less likely to break, less maintenance.

Just wanted to throw some ideas out there. Feel free to tear into them!

"One hundred million lemmings can't be wrong!"
- Graffiti

 

[whisper]

Hafnium is a beautiful metal, just beautiful.

Hafnium is a beautiful metal, just beautiful. It's also very useful, because it likes to give up electrons to the air around it.

Hafnium excited with a low power microwave produces wonderful blue plasma of pure electrons and a surprisingly substantial amount of very useful heat.

66 ounces of hafnium excited by microwave energy produces enough electrical and thermal energy to power a predator size aircraft for 1 week.

Check it out, the information is out there on the net.

If "you" are dreaming it, It's probably already been built.

Cheers

 

[drag]

I suppose you'll be the first (and last) volunteer for such a suit ?

 

[whisper]

hmm.. why would that be?

Hafnium is inert, that is to say you could eat it if you were so inclined with no ill effects beyond the obvious gastronomical protestation .

Seriously when excited it does produced non-ionizing gamma radiation that would indeed produce, uncomfortable side effects to put it mildly. But the gamma radiation produced is low energy and with a modest amount shielding, not a problem.

I'm sure that it's possible to build a compact system say the size of modern re-breathing scuba apparatus which can comfortably power an electric vehicle the size of an civilian suv.

Just a thought.

cheers

 

[drag]

Greetings !

Didn't find the info. Where's the energy coming from ?
(Only possible thing I can think of is fission = not user friendly.)

Peace and long life.

 

[zesban]

From what I read it would appear that Hafnium must be first be placed into an excited nuclear state, known romantically as Hf178m2. This extra nuclear energy radiates over a 31 year half life, making Hafnium pretty unique as most isomers placed in an excited state have a half life shorter than a minute. The energy it sheds is given off as a gamma radiation and after it collapses to it's next state, it has a 7 second half life before returning to nuclear ground state.

A scientist at the University of Dallas claims that he has caused Hf178m2 to collapse into it's next half life stage immediately, as opposed to taking 31 years to do so, which yields all of the potential gamma radiation at once, by exposing the isomer to x-ray radiation. Only he has been able to perform the experiment.

According to his results, you get a 50-60 times energy return on the gamma radiation shed from what you use in the x-ray trigger. This is potentially a very promising energy source, and weapon. The thing is because this isn't a release acting the weak or strong force, but simply on the energy state of the particle, it doesn't fall under any known non-proliferation treaties. This has naturally grabbed the attention of the U.S. Military, though the scientific community at large has a problem with this as no other scientist can verify the results. They think this process isn't actually possible and the military is chasing phantoms while angering the international community by persuing such a weapon.

Check it out:

http://www.globalsecurity.org/wmd/intro/hafnium.htm

 

[drag]

Thank you for the info - very interesting, zesban.

At any case then, even assuming that it works and that a
small X-ray emitter could be used, the big problem for a backpack
generator of this sort, as I suspected in the first place, would still
be shielding and energy conversion of the gamma radiation.

Live long and prosper.

 

[zesban]

I agree. While it would be suitable as a weapon, I think there are better avenues to explore for energy sources. I had made the suggestion of using an RTG, or Radio-isotope Thermal Generator a while back. I still think it would be pretty cool.

An RTG produces electrical current based off of the Seebeck thermalelectric effect. Basically it takes two units, coupled together, that have radically different thermal states. The excitation due to thermal energy of one unit creates pressure which then flows to the other unit, generating current.

See the following link:

http://www.wws.princeton.edu/cgi-bin/byteserv.prl/~ota/disk1/1994/9423/942306.PDF

While the RTGs discussed weigh approximately 1-2 tons, they also produce anywhere from 9-20 Watts constantly for at least a 30 year lifespan. If these generators could be scaled down for uses in the armor I think they would make an effective power source.

See, the community has developed this carbon fiber nanotubing that acts like muscle. When you apply an electric current to it it contracts and then relaxes when current is removed. But it's 100 times as powerful as muscle, approximately, per similar densities.

http://www.eikos.com/articles/carbnano_routetoapp.pdf
(This is a lengthy article but discusses a number of applications for this material. Look under Electromechanical Devices, it's in the second half of this section.)

The generators would provide the current needed to drive the nano tubing throughout an armored exoskeleton. These methods would eliminate a lot of moving parts making the suit pretty reliable for away missions and with such an efficient power source you include a number of other tools.

The suit itself would have to be as lightweight as possible. I would suggest components of Liquidmetal Steel and Tungsten alloyed or Ceramic Aluminum composite. This would provide a very strong, very corrosion resistant, light weight, and heat resistant material with which to craft the armor. Any heat generated could be fed back into the RTG to improve efficiency.

http://www.liquidmetal.com
http://www.astromet.com/alumina-ceramic-amalox68.htm

Right now I can't decide between the steel or the alumina. I wanted to bounce these ideas off of the posters here as a lot of good knowledge is being thrown around here.

 

[drag]

Titanium could be good too.

The muscle idea sounds cool. Though, the "good old"
motor would probably be better for the major parts.

 

[zesban]

The problem with titanium by itself would be that it isn't as resistant to corrosion and not strong enough. When you alloy it with steel it would solve these problems, but then it is heavier then these other materials.

Motors are nice, but they break. Often right when you need them the most. They also require a lot of chemicals, i.e. coolants, lubricants, etc...

By eliminating the moving parts you create a much longer lived field suit. The "muscles" would have the capabilities to lift a ton or more and be approximately the size of a man's arm in volume.

If we had a motor with no friction that didn't need coolant or other chemicals that need regular replacement than I would consider it equitable. Or if the motor could far outperform the nanotubes. I haven't seen anything like this out there though, but I'm always willing to be enlightened.

I like that people are still talking about this stuff though. Very cool, and I bet it'll happen, a lot sooner than people think too...

 

[whisper]

Very true, exposure to Gamma radiation is very harmful; Gamma rays are stopped only by direct collision with an atom and are therefore dangerously penetrating.

Conventional thought would have you strap on several hundred kilograms of lead to reduce the amount radiation you are exposed to. Now enter if you will the world of Plasma Physics and Magneto hydrodynamics; while magnetic fields alone do not stop Gamma Rays, magnetic fields can contain plasma and plasma is where the magic happens.

Here are the principals:

Very High Density Plasma forms a barrier with which the Gamma radiation collides, on collision with the VHDP barrier the Gamma Rays trajectory is deviated to such a degree the radiation becomes briefly trapped within the plasma giving up more energy with every collision.

By the time the radiation moves beyond the plasma it has attenuated to the point that most of the radiation will not pass through the reactor housing and the radiation that does would be no more harmful than the radiation given off by a standard CRT.

The byproduct of the process is heat and free electrons.

Q: What about the heat you say, how could anyone survive with that sort of heat strapped to their back?

A: Now bear in mind that were talking about a containment core roughly the size of a grapefruit.

“In the 1980s, Scott Backhaus and Greg Swift at the Los Alamos National Laboratory realized that compression/expansion action could be used to cool and heat metal plates placed in the path of a sound wave.”

Radio waves also work and have actually been used for near absolute zero experimentation.

I think you see where this is going. Waste heat management was never an issue.

Q: Great what about Electricity, where does that come from?

A: The free electrons are harvested from within the core through electron migration and thermal coupling. Again producing enough electrical energy needed to power an SUV sized electrical vehicle.


Whisper

 

[kirkmcloren]

If you like electron emitters try cesium.

BTW you aren't going to shield a backpack gamma emitter with a magnetic field.

 

[whisper]

Thats correct, magnetic fields can't stop gamma radiation. Plasma on the other hand works wonderfully. Megnetic fields only keep the plasma where and in what shape you want it.

The plasma is the radiation sheild.

Whisper

 

[drag]

Do you have a link on such plasma radiation shields ?
Never heard of this before, for some reason.
It could be considered for space applications too, if it works.

Peace and long life.

 

[kirkmcloren]

Thats correct, magnetic fields can't stop gamma radiation. Plasma on the other hand works wonderfully. Megnetic fields only keep the plasma where and in what shape you want it.

The plasma is the radiation sheild.

Whisper

You had it right when you said:
Gamma rays are stopped only by direct collision with an atom and are therefore dangerously penetrating.

Plasma has no enhanced gamma interception. Stipping electron(s) from a nucleus reduces the capture area, not enhances it. Someone yanked your crank when they sold you on plasma as a wonderful shield. A solid has lots more atoms per unit volume than a gas.

 

[whisper]

"Plasma has no enhanced gamma interception."
That is based on scientific theories made when the scientific community had very limited understandings of Plasma Physics. The fourth state in now understood to range from gaseous to crystalline. That’s as much as you can get from me, however you can google for this information as some of it is already making its way to the public domain.
http://www.iop.org/EJ/abstract/0741-3335/44/12B/319


"Stripping electron(s) from a nucleus reduces..."
What you are referring to is a state of Plasma, Ionization. Ionization is simply a subset of a state of plasma, nothing else. "Plasma can be ionized or not"

There has already been a "RADICAL!" shift in ideas and understandings concerning Plasma Physics and Magneto hydrodynamics, terrestrial and otherwise.

So please believe me when I say it's probably been done. I assure you that I'm no quack; I simply was impressed with you general conversation. I however noticed that you all were limiting yourselves by assuming that no suitable power supply existed, or would be viable in the near future. And that is just not true.

whisper

 

[kirkmcloren]

"Plasma has no enhanced gamma interception."
That is based on scientific theories made when the scientific community had very limited understandings of Plasma Physics. The fourth state in now understood to range from gaseous to crystalline. That’s as much as you can get from me, however you can google for this information as some of it is already making its way to the public domain.
http://www.iop.org/EJ/abstract/0741-3335/44/12B/319

The abasract is:
Abstract. Liquid and crystalline phases can be formed in so-called complex plasmas—plasmas enriched with solid particles in the nano- to micrometre range. The particles absorb electrons and ions and charge negatively up to a few volts. Due to their high mass compared to that of electrons and ions the particles dominate the processes in the plasma and can be observed on the most fundamental—the kinetic level. Through the strong Coulomb interaction between the particles it is possible that the particle clouds form fluid and crystalline structures. The latter is called `plasma crystal'. In this review we present an overview on the physics of this new area in plasma physics on the basis of theory and dedicated experiments performed in the laboratory and under microgravity conditions on the International Space Station.
---------------------------------
So where in all that do you get the impression it stops gamma better than the same mass in a non ionized state?

--K

 

[whisper]

Please read the PDF attached to the abstract.

Here are a couple facts.


Metal generally is crystalline.

Strong magnetic fields cannot stop gamma radiation but magnetic fields can alter its trajectory.

Structural alignment is more important than mass and beyond that there are other forces that are more important than structural alignment.

Please don't expect me to explain the science or find all the papers and articles necessary explain all the process it's not something I can do.

So you'll have to take it on faith for now, I’m sure before long it'll show up in Scientific America or the like.

whisper

 

[kirkmcloren]

Please read the PDF attached to the abstract.

Here are a couple facts.


Metal generally is crystalline.

Strong magnetic fields cannot stop gamma radiation but magnetic fields can alter its trajectory.

Structural alignment is more important than mass and beyond that there are other forces that are more important than structural alignment.

Please don't expect me to explain the science or find all the papers and articles necessary explain all the process it's not something I can do.

So you'll have to take it on faith for now, I’m sure before long it'll show up in Scientific America or the like.

whisper

Sorry, I take nothing on faith especially when it is contrary to the established body of science. Only alpha and beta are deflected by a magnetic field. Gamma is not.

You don't have to find papers and articles. Just tell me where you got the misinformation you already have. What papers were they?

Remember gamma rays are used by astronomers because they are not deviated by magnetic fields during their travels over intergalactic distances.
They point right back to their source.

Kirk

 

[drag]

There are no strong magnetic fields in intergalactic space either.
But, I too never heard of magnetic fields affecting
gamma ray trijectory.

 

[russ_watters]

Keep it on topic guys - whisper, that stuff sounds suspiciously like Electric Cosmos. We won't be discussing that in the engineering forum and likely not at all on this site. Please obey the rules of the forum.

 

[kirkmcloren]

There are no strong magnetic fields in intergalactic space either.
But, I too never heard of magnetic fields affecting
gamma ray trijectory.

What you are trying to perceive is the affect. If the distance is short, as in a lab, the field's effect has to be large enough to be measureable. If the field is quite weak and it's effect quite small it would still be easy to see as intergalactic distance is many times the distance in the lab. A very small affect would be large over that distance.

Kirk

 

[zesban]

Alright, coming back around to the topic then.

I believe we do have the capability for the power source. RTGs I think hold potential and there are probably even better solutions that already exist or are close. I think we should focus on one that can generate steady amounts of electricity from a stable system with a long life span. The reason I would argue this is that I'd like to see the muscle like nanotubes provide the mechanical energy for the armor from this electrical source.

The problem here is even if plasma fields could be used to harvest gamma radiation, the original idea was to have the Hf178m2 provide, unless I'm mistaken. And it would appear that this is not likely, as the experiment itself is so far unable to be reproduced and seems to not be possible.

One possibility may be a Helium-3 fusion reactor. This exciting material has been concepted to fusion with itself and release no radiation. Only appropriate heat shielding would be necessary. Further, proof-of-principle has been established that it can fusion with Deuterium with very little radiation given off.

http://www.space.com/scienceastronomy/helium3_000630.html

Also, a more mundane solution may come from a company called UltraLife batteries. Their Lithium ION cells are flexible in their configuration and rechargeable. Further, they appear to produce a decent current.

http://www.ulbi.com/market-display.asp?ID=10

Feel free to contribute further ideas, this forum has been great for sharing ideas on this!

 

[FutureRNS]

Helow. I'm new here, so I can't undersand what's the problem? Power armor has got basic parts:
1) Engine that creates energy. It could be anything from micro nuclear or hydrogen plant to biological synthesis.
2) Armor plating. USA army has been developing new tipes of armor for tank. Lates polifabric ceramical armor could be used to cover power armors. It is light ant has got good qualitys even in few centimetre thick. New researches of fiber produce by spiders
could be useful here too. It's incrediblly stong and elastic. But you should understand that you can't make power armor resistant to everything. Basicly it should be inpenetratable for bulets up to 50 cal.. RPG and 50 cal. could penetrate every armor of up to 3-4 cm thickness.
3) Muscular system. I read about fiber muscles long time ago. It's the most progresive solution I can think of. It is highly tolerant to heat, pressure or other factors. It doesn't need other machinery to work (not like hydraulics whitch needs masive compresors). Fully operational unit could produce speeds up to 30-50 km/h, jump to 6-12 meters high.
4)Control system. It would be imposible to move your leg forwards, so no pressure plates would work. But I think I found interesting solution. When you move your arm or leg your brain sends a neuro signal for muscle. Everything is like with a fiber that is developed already. So you could intercept these signals and produse into electronical signals. This way power armor wouldn't be a suit it would be extension of human body.
5)Visual system. I think everyone would agree that it isn't a problem :) New technology cameras would help to see targets that is 2-6 km away. When connected whith weapon, it could improve targeting system. Hitting a moving target wouldn't be a problem even in distance of 2km.Such weaponry is already in development or production.
6)Life suport system. Power armor should protect what is inside. But armor isn't everything. Soldier should be protected from biological weaponry. So it should be hermetic container whilth individual air suport or air cleaning system.

With such power armor, soldier could be be exteemly mobile, invulnerable to bulets and could take down 10-20 soldiers in close combat and even more in distance. So it's future of warfare.
By the way, sorry about my grama, Engish is my second language. I'm from lithuania :)

 

[zesban]

Yes, it's interesting how more and more we're able to get metals to act like polymers. This over all but the power source, is probable the greatest advancement we've toward developing such a piece of technology.

I still think the power source is, like most things that are in development, the most critical hinge on which a project like this is fixed. Unfortunately, this also seems to be the slowest developing component. I wish we had more info on viable power sources, but crawling the internet even doesn't seem to yield much in this way.

Anybody out there got some info on compact power sources?

 

[wgayton]

Good stuff

It’s truly amazing, seems like a powered suite has all the pieces in place to a large degree except for the power supply. I think I remember seeing something similar to what whisper was talking about on darpa's website sometime ago, I'm trying to find it again. Anyway I think it was about very small reactors for robotic spy submarines. If I can find it I’ll post a link.

How long would you need to power such a suit and how much power would it consume? It may not be necessary to have a very advanced power supply.

Just a few hours at before a recharge would probably still make something like this very effective.

My thoughts.

 

[FutureRNS]

Yes, it's interesting idea to use stored energy. But it would greatly reduse the efectivnes of power armor. Still maybe it's the only solution for this time. I found interesting product that is already in stocks. It's simple batary, of unusual thikness. one batary is only 0.6 mm. You can find all data about Powe paper here http://www.powerpaper.com/u/3_technology/batteryspecs.htm .
But i don't think that it would be good solution. I'm looking into a beter perspective. Nano-technology. It is said that nano robtos will be in production after 2 to 5 years. It isn't very long. So every power armor created would be opsolyte when nano-technology will be developed. But i think that there is a formu for this technology. But by the way i wanted to ask what is power usage of the muscle fiber? I think that i saw about it on tv and they said that is very low.

 

[zesban]

I'm not sure what power would be needed to drive the nano fiber. Most people researching that technology are interested in it for its tensile strength currently. This property is unique to certain layouts in its structure and was an accidental discovery. Never-the-less, it has fantastic possibilties for an armored suit, but nobody is reasearching what it would take exactly to power such a device, to my knowledge anyhow.

If anyone finds any figures on this it would be interesting to seen them. We know the human body can produce enough power to drive its muscular system readily enough, so I don't imagine this to be too taxing on a power system, but real figures are always better than educated guesses.

 

[notal33t]

Darpa & Nanotech

One wonders if DARPA's involvement in the whole area of nanofiber research isn't going to ultimately bury the construction of such projects as the space elevator under a blanket of 'national security interests', due to this whole area of nano-armor. I hope I'm wrong, but I've run into several attempts at misinformation and, unexplicable (sic) ridiculing of the concept of using CNT, by people one could term defence establishment types.
It's would truly be a shame if, 'defence establishment types', have placed civilian nanofiber technology on it's KILL list, because of 'nano-armor'.

 

[zesban]

Indeed, a frightening inference. Regardless, unless a suitable power source is found the point is moot. I haven't had much time to research potential power sources or what the power requirements would be for the suit myself. Any ideas, figures, etc...?

 

[lucien86]

I have been working on things rather like this for many years, I was mainly looking at
the design for bipedal robots but power suits have much the same problems.

Yes power supply is the biggest issue. Nuclear reactors, biochemical engines, and batteries are basically out because of various reasons, but basically don't produce enough energy.
The simple and only current sane solution is our old friend the internal combustion engine. Its light weight strong reliable and above all produces a lot of energy. This can then drive an efficient pneumatic or hydraulic compressor, electrical drives or even mechanical half shafts and clutches.
Another potential solution is steam drive, this can deliver quite a lot of power for low weight but generates a lot of heat. Steams real problem though is its safety aspects, - if anything goes wrong it tends to explode with shrapnel, or broils the operator alive.

These are some old robot technologies developed in the 50's and 60‘s, mostly by the American military, most of these come under the heading called pitons. (Pitons work rather like pneumatic rams, the movement comes directly from a sliding piston, but they are driven in a different way.)
There are several kinds of pitons. -
Petrol pitons use tiny pulsed petrol explosions inside the cylinders themselves, they were very powerful but unstable (I don't know if they ever worked).
Hyper-sonic pitons used hypersonic shockwaves to move the pistons, they were incredibly fast and powerful but extremely dangerous. The shockwave generator was basically a powerful whistle and if it failed in the wrong way the energy could leak out killing anyone within a hundred feet or more. Also although the drive system was very lightweight the shockwave generator itself weighed several tones. Shockwave machines tend to explode if 'anything' goes wrong.
Rocket pitons used a rocket engine to provide the impetus (probably similar to the V1's pulse jet), again a lot of power and again subject to self detonation.
Vacuum pitons were more sensible and used strong vacuum pumps rather than compressors, but are otherwise quite similar to modern pneumatics.
Electrical pitons were the strangest of all, they used electrical fields to move the pitons and they are quite different to any technology used today. As far as I know they were pretty close to genuine positronics and used a 'very' high field strength. Surprisingly very fast and very strong. Completely invulnerable to EMP themselves but unfortunately a very strong generator of EMP and radio noise. Electrical pitons could well have been connected to a nuclear fusion engine developed in the 50's by the American military that used the same technology - it was one of the programs destroyed by Kennedy and nothing is known about it now.
The final type of piton used a wonderful idea, it was driven by a battery that stored energy by bending space directly, not surprisingly it is entirely theoretical. The plus side of such a battery is that it can store energy almost without limit. The downside is that space is slippery, and if the batteries ultimate limit is reached or anything goes wrong all the energy is released instantly, and it explodes with enormous force.
There is a legend that this battery actually was built and has been used in teleportation experiments, it was essentially a giant electrical capacitor with a colossal electrical field inside it. (The legend says that it was powered by 8 500 megawatt power stations). The 'Hoover' teleportation experiment had the vile motto (something like) '6 seconds from Moscow'.


The real point about all the above though is that any really high energy system has a high tendency to fail, and particularly to explode. The same is true of liquid oxygen systems.

At the end of the day it looks like its sad old petrol that's the solution. In the future some kind of system using muscles may be possible BUT it is really decades away. The real problem with muscles is that they get damaged constantly in use so they need to be self repairing, I don't see how synthetic muscles can (ever) do it. A living machine using natural muscle seems to be the real best solution but would be colossally difficult to construct and is practically identical to a well known experiment by a certain Dr Frankenstein. (pictures greens and animal rights protesters chasing me with pitch and burning torches)