Robot helicopter’s impossible tricks

“Controls” is the branch of engineering that deals with the regulation of moving things. Thermostats and cruise control are the obvious examples, but control systems show up all over the place: temperature control, power control, attitude control… anything that, if left untended, is likely to become a puddle, a crater, or a ball of flame. Behind each one of those regulatory control systems is some code, probably written by a grad student, that spells out how the system should behave.

I was once a controls grad student, and one of the things we learned is that, once you’ve figured out how to control something, it’s not very hard, mathematically speaking, to control it amazingly well. Crank up the gain high enough, and you can make a tractor tap dance or a jet skywrite in cursive. In theory. The situation is similar to the old Archimedes quote “Give me a lever long enough and I can move the world.” It’s a nice line, but I checked the catalog, and they’re currently back-ordered on those super long space levers.

From a practical point of view, to do amazing things with control design, you need fast, accurate sensors with very clean signals and fast, accurate actuators with very clean response. This makes for a system that is heavy, hot, power-hungry, and very very expensive. Or rather, it always did until now. Everything is getting so much smallerer and betterer that old-timers like me can scarcely believe what’s possible. This is the best time ever to go to engineering school. Look at what you can build. Behold the insane quadrotor built by a group (of grad students!) at Penn.

Pardon my French, but that’s some crazy shit right there. Every working controls engineer in the world is wishing they were starting grad school right now.

The tactical value of these systems is obvious. Imagine snooping spy-bats that can perch on walls and quietly eavesdrop before flitting away into the night. Here’s a nice piece on perching planes at Stanford.

Prepare to see an unparalleled rush of innovation in micro-aircraft.