Walk Under His Huge Legs and Peep About

Shakespeare. Julius Caesar. What, everyone else gets to use his stuff for titles.

Got meself thinking about tanks, like you do, and that—as it does—got me to thinkin' about mecha. I have them, in my SF books; not going into more detail than that. But anyway, so I was thinking about how to do them, in terms of power and whatnot.

I like, in my books, to use real things as bases for my conjectures. So: ASIMO! ASIMO stands 1.3 m tall and weighs 54 kg. So if it was 10 m tall, it'd weigh 24.6 megagrams—we're assuming future-y materials that are that light, but can also support that weight. Now, ASIMO needs a 6 kg battery to run for an hour (at the mecha's scale, that comes to 2.7 Mg)—but then again, the mecha can just use atomic batteries, kick the training wheels off your quaint "electrochemical" toys. Hey, Gundams have fusion reactors, you know.

Now, 'course, ASIMO might be a little light. So how about BigDog? Certain steampunk sissy-pantses of my acquaintance think it's creepy; I think it's awesome (robot mule for the win!), and they're working on a muffler for it. Anyway, if we assume the thing would stand roughly 1.5 m tall, bipedally, that (since it weighs 110 kg) gives us a 10-meter mecha of 30.7 Mg—much more reasonable, considering the thing's gotta have weapons and armor. Incidentally, that's only 300 kg heavier than a Sherman tank.

Okay, so we got a weight, and a generator. Next, power. A BigDog uses an 11.2 kW go-kart engine; a Sherman's engine is 253 kW, or about half again the Tesla Roadster's engine. So plainly outputting sufficient power to drive the thing is not going to be trouble for a 24th-century tech-level. Especially because, remember, mecha don't walk on level terrain, they have tracks in the soles of their feet. Walking is only for bad terrain—they're designed to go on that nearly 50% of the landmass that wheeled and tracked vehicles can't get to.

Controls? Well, probably it'll use variations of most of a BigDog's proprioception systems, to keep its balance. As for the actual controls, the setup I keep picturing is basically an XBox/PS2 controller, except full-size joysticks, set into each armrest. Each would have two triggers in front, worked with the index and middle fingers, while the thumb works four buttons, set in the top of it. Rather than controlling the movements one-to-one, probably its movement programming will be a lot like in an FPS—one stick controls direction and speed the vehicle walks in, the other determines facing and point-of-aim. The triggers activate the weapons, of course, while the buttons do the other functions.

You're gonna want it to have weapons it can pick up, like an anime mecha: hands make a great basis for modularity. Now, you're probably gonna want something simpler than a trigger that has to be pulled, maybe male-female linked surfaces on hand and weapon, and then firing is done electronically. You're also going to want built-in weapons, though, like shoulder guns and whatnot. The way I picture it, you pull one left trigger to fire the weapon in the left hand, while the other fires the weapon on the left shoulder (or in the left kneecap, left side of the head, you know); right triggers fire the right-hand weapon and right (other body-part) weapon, respectively. I dunno, does a medium tank that can go on virtually any ground terrain and fire four weapons simultaneously sound like a bad idea? Plus gives the psychological advantage of being a mobile colossus whose hands rain down death upon the enemy.

PS. My robots use a similar proprioception system. I realized something funny, actually: they use only about 10% of their processing power for conscious thought, same as us. What's the rest of it doing? Watch how slowly ASIMO has to move, and consider yourself answered.