Is it possible to build a jaeger?

[ZedNova]

After seeing pacific rim and it's awesomeness, i got to thinking; Would it ever be possible to build monstrosities such as the jaegers? And would they really even work?

Edited October 30, 2013 by ZedNova

[Fitzy3]

Yes, with some mods (like infernal robotics), you could make some pretty cool creations.

[Xeldrak]

In reality? Well, I guess you could probably build something like them - but I don't think they would be very practial. Probably prone to break under their own weight.

[Seret]

First of all, I've not seen Pacific Rim, so I don't know anything in particular about the giant robots in it. But in general no, sorry there is a maximum practical size for a vehicle.

Take tanks for example. The Germans were trying to build some really ludicrous sized tanks in WW2, they actually fielded one which was nearly 190 tonnes. The problem with this is that their mobility sucks. Modern tanks have stabilised at about a maximum of 40-50 tonnes, adding any further size and weight actually makes them less effective.

Part of the problem is that if you scaled a vehicle up its weight would increase at the cube of the size increase, but the area of it's tracks only increases at the square, so the pressure per unit area goes up. Ground pressure strongly affects off-road performance. Total weight also limits what bridges the vehicle can use, as not all rivers are fordable.

This problem means that if you wanted to create a really big vehicle you'd want to build it very low and wide, to give it lots of area in contact with the ground. Tall and narrow (ie: humanoid) is the exact opposite of what you'd want. In reality giant humanoid robots would have immense ground pressure, and would simply sink into the ground and get stuck when they tried to move. Contrariwise, building a very large low wide vehicle would also be of little use, since it wouldn't be able to use roads, tunnels, bridges, couldn't enter built up areas, etc.

There's a reason why tanks haven't increased in size or weight much over the last few decades. They're pretty much at their maximum practical size and weight. Tank designers are now looking for ways to decrease the weight of the armour while improving performance. A decent airmobile tank is highly desirable, but all the attempts so far have been very limited compromise designs that aren't able to stand up to proper tanks.

[dr_jt]

There is also a limit on what can be moved and how fast it can be moved. The arms of a jaeger would be many 100 of tons to be effective as a battering ram. i.e. punching. The hydraulics would be massive for it and the speed would be limited to how fast you could pump the fluids around. Tying to armor all of the hydraulics would also pose a problem. Break a couple of lines and the arm is now just a useless weight you have to carry around. The whole leg assembly would not only have to move quickly but also carry the massive weight of the body and arms. All on just a couple of hip joints which would be of great concern for failure. To add more insult you would have these mega ton robots standing on a very small surface area. Just look at your feet and how small they are. The robot would have a hard time walking about because it would sink into the ground and in some places like the deserts or jungles they many sink quite a way into it.

[Canopus]

Just take those "Anti-Kaiju missiles" from the Australian Jäger and put them on an aircraft or a ship, much more effective than a giant robot that just can't work in realty anyway.

Edited October 31, 2013 by Canopus

[Seret]

Right, now having seen Pacific Rim I'm going to double down on "hell no". There was absolutely no attempt to make it even veer towards reality. It was just bubblegum celluloid that you weren't supposed to think too hard about. 8 Chinook-sized helicopters lifting thousands of tonnes of giant robot? Yeah right.

[TwoHedWlf]

Hah, just watched it a couple days ago. Another thing in addition to how fragile they would be in reality, and ignoring how catastrophic it would be if they simply fell over... They move WAY too fast. Just the way they walk they'd have to be forcing their feet downwards rather than just accelerating under gravity, and forcing their foot down at that rate would lift the rest of the Jaeger into the air. It would just look weird, and then it would probably fall over.

It's tech magic, you don't nitpick how magic spells work in a fantasy movie, it's the same kind of thing. It's bigass robots beating up giant monsters, it's not meant to be shakespeare...

Although...

Romeo, romeo, wherefore art though battlemech?

[drakesdoom]

The closest to real large robots I have seen were AC 2 and 3 where the were relatively short and slow. Any fast movements happened with the assist of thrusters.

Battletech are also not to ridiculous. They are more in line with size and weight of current tanks, they get somewhat heavier but the heavy ones do have a lot of mobility issues. Falling down does cause major damage if it happens.

In both cases the lynchpin is that they are using fusion reactors with crazy energy outputs that only weigh 20-40 tons. I believe that is completely beyond what is theoretically possible unless you don't mind letting some radiation out whenever it is on.

[Fr8monkey]

No... Good entertainment; but physically impossible using current or near future technology.

http://www.zimbio.com/Beyond+the+Box+Office/articles/TzjPYG8JMuA/Pacific+Rim+How+Engineer+Sees+Jaeger

Edited November 18, 2013 by Fr8monkey

[Nuke]

a jaeger didnt seem like the makers of that moving understood how structural engineering works. like that ship/club would have broke in half if not supported by buoyancy.

Just take those "Anti-Kaiju missiles" from the Australian Jäger and put them on an aircraft or a ship, much more effective than a giant robot that just can't work in realty anyway.

the kaiju have their own structural issues as well. meat is heavy and doesnt absorb damage very well (its main advantage is the ability to self heal, not absorb energy, see zerg). i found out on a hunting trip some years ago what kind of damage a tiny 7mm round can do to a deer's spine. now take a 15 inch battleship gun and shoot a kaiju with it. i figure you will get the same result.

The closest to real large robots I have seen were AC 2 and 3 where the were relatively short and slow. Any fast movements happened with the assist of thrusters.

Battletech are also not to ridiculous. They are more in line with size and weight of current tanks, they get somewhat heavier but the heavy ones do have a lot of mobility issues. Falling down does cause major damage if it happens.

In both cases the lynchpin is that they are using fusion reactors with crazy energy outputs that only weigh 20-40 tons. I believe that is completely beyond what is theoretically possible unless you don't mind letting some radiation out whenever it is on.

i think battletech is the most believable, but still far from practical (its primary awesomeness point is that it has awesome gameplay mechanics). i dont think its beyond the capacity to build something like that. loads are somewhat acceptable. you might have issues in your heavy and assault classes (i always preferred mediums and lights myself).

as for the reactors, dont use the tokamak as the yardstick for how big a fusion reactor needs to be. physics require it to be that big because of probability of divergence and the fact that gyroradi are finite size, but thats entirely due to the toroidal nature of the core. other forms of fusion like polywells and dpf could result in reactors considerably smaller. the tokamak will go down in history as the brickphone of fusion reactors.

Edited November 19, 2013 by Nuke

[Seret]

a jaeger didnt seem like the makers of that moving understood how structural engineering works. like that ship/club would have broke in half if not supported by buoyancy.

Yeah, that bugged me too. There was just no appreciation of the fact that you can't just scale things up a hundred times with the same materials and expect them to work the same way. Very large and very small things just don't act the same way things at the everyday human scale do.

[tom1499]

I didn't watch it, but my mum and sister did, and from the snippets I caught it was exactly what I expected, just another battleship/independence day/transformers.I mean really: "The neural pathways must be connected in a special way because uhh...yeah" I'm not even sure what the big fan on the front was for? Cooling? You don't cool a giant robot with a jet engine, it doesn't make sense!

I don't mind hollywood churning out these midless explosion-fests, but for the love of god STOP CALLING IT SCI-FI! There is no science! It is fantasy! GIANT ROBOTS PUNCHING GODZILLAS IS NOT SCIENCE! Just FICTION!

[Seret]

just another battleship/independence day/transformers.

It actually wasn't quite that bad. It was unrealistic and dragged out just about every cinematic cliche there is, but having Guillermo del Toro behind it meant it didn't descend to Michael Bay level. Hardly del Toro's finest work though.

[Motokid600]

Two hundred years from now I could see something like it. When humanity is processing multiple planets worth of resources. As is such a build would bankrupt the entire planet.

Then there is the practicality. Biped mechs would be nice for the versatility, but they'd have to be small. As others have said skyscraper sized mechs would collapse under their own weight. So a Biped that's the size of a mach truck on end would be better. If that..

Then theres power. That solution is more sci fi then the mech itself. Motor control would have to be revolutionized as well. Hydraulics are not fast enough. A new method would need to be developed. Something that can make such a machine move with the dexterity of a human. On top of all this.. humans would NEVER pilot these machines.

Armored Cores are my favorite mechs. But if humans were actually in them they'd be spam in a can. Anyway if society gets to the point were the development of these super destructive machines is waranted god help us.

Edited November 19, 2013 by Motokid600

[Wesreidau]

Seret is unfortunately incorrect about tanks in some respects.

1. The central engineering component of a tank is the turret ring. This element determines the recoil length of the gun. More powerful guns with more recoil require larger rings, which in turn require a larger chassis to accommodate the ring. This determines the actual size of the vehicle. The German superheavies were being built to accommodate a 128mm gun ordinarily fired from an open platform where recoil length was not originally a design concern. Modern Western MBTs use much more efficient penetrators, 4 kg compared to 28 kg, and so the weapons are much lighter. Tanks of that size were abandoned because changes in penetrator technology made such superheavy guns unneeded, which meant such large turret rings were unneeded.

2. Because of their wide chassis, numerous heavy tanks had better cross-country performance and lower ground pressure than their weight class would suggest. Tiger tanks in Italy could maneuver in terrain Shermans bogged down in, in spite of the power-to-weight ratios or lower top speeds. The Maus was also noted for a very reasonable ground pressure.

3. Tanks haven't changed in the last few decades because current tanks are all a few decades old. MBT design basically ended with the cold war and had plateaued towards its end due to three factors; the effectiveness of sub caliber penetrators and gun-launched ATGMs made 120mm~ guns sufficient for all threats, the elevated lethality of the weapons made detection and fire control systems more worthwhile investments than armor or gun bore, and lightweight non-gun threats to armor became prevalent and effective.

What does all this mean for Jaegers (why such silly Japanese nonsense has an honest German name I have no idea)? First, I doubt there is any weapons system mounted on a Jaeger, aside from its fist, that requires such an enormous and expensive 'carriage'. Second, because of their small footprint to tremendous weight, such a vehicle would be incapable of traversing terrain less solid than nonporous rock, and would step through a road surface like a thin crust of ice on a snow drift. Third, weapons capable of destroying it are available to any third-rate regional power, fired from man-portable systems easily concealed from the Jaeger, which would be more than capable of crippling the entire complicated weapons system with so much as...

An Arrow to the knee.

Yes, this whole post -was- leading up to that.

[LaydeeDem]

Could we? Of course. Is it practical? No. Pacific Rim was supposed to be a fun movie filled with explosions and monsters. The Kaiju would never be able survive on Earth. The gravity is too high and the oxygen content in our atmosphere is too low to support life that large. They would die of exhaustion the moment they stood up.

[air805ronin]

I get the feeling I'm in the minority in that I can turn off my science brain and just watch the movie to be entertained. I went in expecting a Godzilla v Gamera level movie, not a dystopic science fiction masterpiece. I was not disappointed.

that said...they kept saying X number of diesel generators per muscle strand. I don't know if they were powering hydraulic pumps or if the muscular architecture of the robot was powered by electricity. Then the hilarious moment where digital vs analog becomes a thing... Oh and the weird dual person walking clunkily translated to movement in the bipedal robot?

It was a big monster popcorn flick. I will look at it as nothing more. I really loved it as long as I look at it that way. If I overanalyze it, it would destroy it.

[Seret]

Seret is unfortunately incorrect about tanks in some respects.

Hey, I actually don't disagree with most of what you've posted, but the reason I brought up tanks at all was to make the point about geometry and ground pressure. As you say, humanoid robots are about the least optimal shape you could choose. A vehicle with the mass of a Jaeger would have to have a huge area in contact with the ground to avoid getting bogged, which would necessitate a fairly wide squat shape. In fact, such vehicles already exist, such as Bagger 288.

I doubt there is any weapons system mounted on a Jaeger, aside from its fist, that requires such an enormous and expensive 'carriage'

I think this is the main point here. Not only would it be incredibly difficult to make a big angry robot, there would never be any need to.

[nhnifong]

In the movie, they said the jager had a "solid iron hull with no alloys" which is hilariously stupid, like the rest of the script.

But anyways, if you wanted to be true to the movie and make it out of cast iron, the answer would hell no.

[Nuke]

as a movie i thought it was pretty good. but it was so full of obvious technical mistakes and annoyances. every time they tried to explain any of the technology i had to facepalm. analog tech! why? analog systems are so dead that its hard to find people who know how to build them. unlike digital systems which everyone and their mother seems to know and understand. but you keep on watching and at the end of the movie you didnt feel ripped off.

one big pet peeve of mine with movies, is how grossly they underestimate the effectiveness of modern weapon systems. after seeing what a simple full metal jacket rifle round can do to meat, that big M61A2 vulcan 20mm gatling gun (firing 110 rounds a second!) should have ripped a massive wound in the side of that kaiju. especially if equipped with du rounds. depleted uranium is really good for projectiles because its liquid state is so small to be no-existant, it essentially goes from solid to vapor instantly on impact, resulting in a devastating explosive effect. why just planes, why not artillery, 105mm howitzer. such a large beast would be hard to miss, even from several miles out. lets just face it meat is easy to mutilate with weapons of war.

Edited November 20, 2013 by Nuke

[nhnifong]

Really great movie for jarheads with half a brain.

[Nuke]

i didnt exactly go in expecting shakespere.

[Seret]

In the movie, they said the jager had a "solid iron hull with no alloys" which is hilariously stupid, like the rest of the script.

But anyways, if you wanted to be true to the movie and make it out of cast iron, the answer would hell no.

Yeah, I did wonder why they were saying that like it was a good thing. Alloys were created because they outperform non-alloys. About the only reason not to use them is cost.

[ZedNova]

Really great movie for jarheads with half a brain.

I don't know, i thought it was pretty entertaining. Although unrealistic.