Sunday, November 30, 2008

What would it take to bring down a t-rex?

i asked myself this question on friday morning, and this is what i drew in answer. i went with an economic design. a "this should just about do it" design for a military group sent back to the cretaceous.

the idea behind the gun is basically to satisfy the needs of the user as best as i could imagine them. it has to be powerful, hence its girth and size and heavy dutiness, it has to be fast and maneuverable, hence the legs (ill explain in a bit), it had to be small enough to be able to move around in a jungle, and then later in hallways on space ships and bunkers, and it had to have enough room for fuel, a motor/engine of sorts to power the gun, legs and computers and equipment on board, and ammunition (which the guy using it would carry in big chains as well as a compartment on the side of the gun to feed it in), looks like it could be mass produced without too much difficulty, looks sturdy, and also look kinda scary.

so the legs. basically the idea of this is to enable one man to be able to bring down, with as little effort as possible, a creature with the same size, toughness and ferocity as a tyrannosaurus rex. inside the guts of this contraption would be a shit load of accelerometers, a gyroscope, radar/sonat, and tons of sensors that would literally read the input given into the handle by the user, as well as it would use blue tooth or something to transder information taken by a camera inside the guys visor which would also guide the gun (like an apache helicopter pilot has. the giant machine gun aims where he looks). and so anyway, it takes this information and accomodates to the users actions. so what this means is the guy could swing that thing around like a pistol. if he wants to do a 180 and shoot behind him, all he has to do is turn, point, and shoot like he would with a pistol, and the gun will do what needs to be done to get itself into position. imagine a mix between the darpa dog robot cargo carrying thing, and the doll head/spider bodied thing from toy story. and maybe a little johnny 5.

note: the legs under the big green fuel tank and engine encasement are shorter than the legs on the other side, though id imagine they would be attached to some sort of framework that could swivel around to so it could straighten all its legs out and still keep the gun level

i also tried my hand at a different technique on the gun for this. i did it with a blocky digital style, sort of like how id like to learn how to paint with photoshop, rather than just color in simple linework. and then hopefully ill be able to learn how to do that and itll help me with my portraiture and even just painting in general. and then the guy was done in markers, but i sorta wish i pushed his colors further


Anonymous said...

Can I begin to describe the technical inefficiencies in the design of this walking turret?

Tom Rhodes said...


Anonymous said...

The first thing I think of when I see it is "weight". The thing must weigh at least a 100-120 pounds. Getting it to the T-Rex hunting grounds requires additional transportation. In isolated and other varying environments, getting fuel to the walker itself would be something of a pain. This is a problem paralleled in the XM134 'minigun' currently in use with the various US armed forces. The unit, while itself mobile, requires a separate power source, literally a battery to drive the motor of the gun. The combined weight of the gun, the mount, the batteries, and the ammunition, make it at worst a logistical nightmare, and at best a gross inefficiency in terms of manpower. It sits in helicopters, gunships, and vehicles. No infantry unit in the world would bother lugging it around. (I'll comment on the legs in a bit)

You mention that the gun is 'powered', suggesting that it's ammunition is either a) energy based or b) a more standard gun/cannon that uses secondary power in order to drive the action of the gun itself (like a chaingun or other rotary cannon). Assuming it is not an exotic energy weapon (I assume they would have perfected cold fusion if such a weapon were to exist), the size of the bore of the gun in your illustration appears to be something in the range of a 20mm-30mm projectile. That is massive, too large to realistically use in such a 'hand held' application. The recoil alone would be nearly impossible to control. A 25mm projectile fired from a variety of weapons produces 70,000-80,000 ft/lbs of muzzle energy. That's a 7 ounce projectile flying at approximately 1000m/s! I suppose this could be theoretically counteracted by increasing the weight of the unit itself, the idea of such a large gun is precluded by a fairly simple fact (which I will also comment about further on).

The legs of this walking turret appear to have up to a metre of clearance for the body itself. Which, all told, is pretty good. Problem being, it would appear to be quite easy to knock over or at least disturb the balance of the unit. A tracked or half-tracked mode of transportation is far more sturdy, especially with the consideration that it is a weapons platform. The recoil of the main cannon would demand that the legs of the walker cease movement and brace for impact (whereas wheels or treads are virtually always in a 'ready' position). Not a huge issue I suppose, but for reliabilities sake, I would feel safer if the unit didn't move like a Hummer on toothpicks; We are hunting dangerous game, after all.

The final, somewhat dubious, fact is that T-Rex's are really not that large. Large Savannah Elephants can reach up to 12,000kg in weight, whereas a T-Rex averaged approximately 13,000kg in weight. Now you might be thinking '1000kg is a lot of teeth and meat', it's really only an ~8% increase in mass. Hunters regularly take down elephants of many thousands of kg with a single shot to the head (typically a brain shot). With a hand held rifle. There are many popular rounds to use against elephants and the other four members of the 'Big 5' African game, but something like .470 Nitro Express is an oft recommended and proven round against something as large as an elephant, almost always being a 'one shot kill' with good shot placement on the part of the marksmen. The round itself, while most often handloaded for a variety of applications, produces anywhere from 4500-6000 ft/lbs of energy (approximately 6000-8000 joules of energy transferred upon impact). Compared to the 25mm projectile described above, it seems rather tame. But if a simple rifle can take down the largest land animals existing today, would a cannon designed for destroying lightly armoured vehicles and even heavier items really be required? I can only imagine the 'overkill' placed on the T-Rex itself. Even without incendiary or High Explosive rounds, the metal slug itself could cause catastrophic and most certainly instantly fatal damage to the soft tissue of a T-Rex.

Really, why have a complicated robot do what a simple tool like a big ass rifle can achieve with ease.

Assuming you are fighting against a pack (if that is the correct term) of T-Rex's, I would place a good deal of faith in the many hand-held anti-tank weapons available to almost every army in the world, much less a professional and well funded force like the US Marines.

I personally would unload enough lead to sever the head of a charging T-Rex, but that's just me. And while I do not currently own something powerful enough to engage something as dangerous as a T-Rex, I rest assured knowing that many varieties of anti-tank rifles are available to the average law abiding, firearm owning, Canadian such as myself. In the case of T-Rex invasions, I would assume most laws on civilian firearm restrictions would pretty much go out the window anyway.

And don't you think the marine could use a bigger knife?

Tom Rhodes said...

Well now I'm gonna have to make a whole new one, Thanks! That was awesome!