> closing a control loop in software (delay leads to instability; if you can't perform a computation fast enough, you cannot perform the control function, thus, certain such tasks could not be performed by a human with pencil and paper).
I agree with your point but I find a certain irony in the fact that a pilot is clearly closing a highly delay-sensitive control loop without doing any math whatsoever.
It's not delay sensitive on the same order of magnitude as something like a dc/dc converter. The relevant time constants in the pilot->controls->control surfaces->attitude->pilot loop are measured in fractional seconds (and when they're not, e.g., in fly-by-wire designs, the loops aren't closed by a person).
The fastest relevant time constant for the control loop of a switching power converter with meager 1 kHz closed-loop bandwidth is measured in fractional milliseconds (you care about poles up to, say, 10x your crossover frequency). For a pretty run-of-the-mill analog circuit like an op-amp, the relevant time constants are often measured in nanoseconds. Heck, even something slow like an audio amplifier has relevant time constants in the tens of microsecond range.
Also, don't underestimate the amount of subconscious math you're doing even for a simple task like walking. Your body's subconscious understanding of physics is pretty damn impressive. The problem is that our brains are pretty specific in the types of problems they're adapted to solving. Riding a bike, sure. Induction motor controller, probably not so much :)
The problem is that our brains are pretty specific in the types of problems they're adapted to solving. Riding a bike, sure. Induction motor controller, probably not so much :)
I suspect that it would be possible to map most control problems onto a problem that the human mind can solve, either consciously or instinctively. I don't think the speed of the loop should be a deciding factor at all, at least when a computer is doing the control. For example, you could map maintaining power supply stability to standing upright just by slowing the problem down and converting the input variables into axes of motion.
To sum up, bumping up the clock speed on something a human could do (even if it took them a thousand years) seems like a very poor criterion for patentability, and I hope the issue is revisited and clarified.
The point parent was making is you can't slow the induction controller problem down because it would yield a completely different output due to the instability.
Slowing down the sort of pen and paper calculation the court ruled on does not change the result, it simply yields the same result more slowly.
I still agree this is probably not a sufficient criterion for patentability though. There are plenty open loop systems that intuitively seem like they should be patentable... for example video encoding methods.
"The problem is that our brains are pretty specific in the types of problems they're adapted to solving"
Brain in fact can adapt it's physic coprocesor to solve many problems it was not originaly intended to solve - see extreme sports, arcade games, steering vehicles, playing live music (and imrpovising it).
I think we could perform many task currently thought to be too computation intesive for human, if there was some clever interface, allowing us to use our coprocessor to solve it.
Like somehow translating problem of controlling induction motor into problem of keeping balance on the bicycle :)
I was going to say the same thing kwantam did about piloting: airplanes generally fly themselves. In the vast majority of situations, all the pilot (ideally) does is add slow and small perturbations. Airplanes without inherent stability, like some fighter jets, are without exception flown by computers, with the pilot providing control inputs to the loop.
I had a professor who was a control systems engineer. They had a helicopter simulation hooked up where you could attempt to fly it both with and without the control system. I don't think I was able to move it more than a few feet without having it flip over when I wasn't using the control system.
And if you want to bring math into it, he was also damn good at solving the matrices filled with hairy PDEs that described the whole system.
I agree with your point but I find a certain irony in the fact that a pilot is clearly closing a highly delay-sensitive control loop without doing any math whatsoever.