Common misconceptions about the complexity in robotics vs. AI (2024)

harimus.github.io

44 points

wallflower

4 days ago


13 comments

jvanderbot 3 hours ago

> Moravec’s paradox is the observation by artificial intelligence and robotics researchers that, contrary to traditional assumptions, reasoning requires very little computation, but sensorimotor and perception skills require enormous computational resources. The principle was articulated by Hans Moravec, Rodney Brooks, Marvin Minsky, and others in the 1980s.

I have a name for it now!

I've said over and over that there are only two really hard problems in robotics: Perception and funding. A perfectly perceived system and world can be trivially planned for and (at least proprio-)controlled. Imagine having a perfect intuition about other actors such that you know their paths (in self driving cars), or your map is a perfect voxel + trajectory + classification. How divine!

It's limited information and difficulties in reducing signal to concise representation that always get ya. This is why the perfect lab demos always fail - there's a corner case not in your training data, or the sensor stuttered or became misaligned, or etc etc.

  • lang4d 2 hours ago

    Maybe just semantics, but I think I would call that prediction. Even if you have perfect perception (measuring the current state of the world perfectly), it's nontrivial to predict the future paths of other actors. The prediction problem requires intuition about what the other actors are thinking, how their plans influence each other, and how your plan influences them.

  • bobsomers an hour ago

    > I've said over and over that there are only two really hard problems in robotics: Perception and funding. A perfectly perceived system and world can be trivially planned for and (at least proprio-)controlled.

    Funding for sure. :)

    But as for perception, the inverse is also true. If I have an perfect planning/prediction system, I can throw the grungiest, worst perception data into it and it will still plan successfully despite tons of uncertainty.

    And therein lies the real challenge of robotics: It's fundamentally a systems engineering problem. You will never have perfect perception or a perfect planner. So, can you make a perception system that is good enough that, when coupled with your planning system which is good enough, you are able to solve enough problems with enough 9s to make it successful.

    The most commercially successful robots I've seen have had some of the smartest systems engineering behind them, such that entire classes of failures were eliminated by being smarter about what you actually need to do to solve the problem and aggressively avoid solving subproblems that aren't absolutely necessary. Only then do you really have a hope of getting good enough at that focused domain to ship something before the money runs out. :)

    • portaouflop an hour ago

      > being smarter about what you actually need to do to solve the problem and aggressively avoid solving subproblems that aren't absolutely necessary

      I feel like this is true for every engineering discipline or maybe even every field that needs to operate in the real world

  • jvanderbot 3 hours ago

    > Moravec hypothesized around his paradox, that the reason for the paradox [that things we perceive as easy b/c we dont think about them are actually hard] could be due to the sensor & motor portion of the human brain having had billions of years of experience and natural selection to fine-tune it, while abstract thoughts have had maybe 100 thousand years or less

    Another gem!

    • Legend2440 3 hours ago

      Or it could be a parallel vs serial compute thing.

      Perception tasks involve relatively simple operations across very large amounts of data, which is very easy if you have a lot of parallel processors.

      Abstract thought is mostly a serial task, applying very complex operations to a small amount of data. Many abstract tasks like evaluating logical expressions cannot be done in parallel - they are in the complexity class P-complete.

      Your brain is mostly a parallel processor (80 billion neurons operating asynchronously), so logical reasoning is hard and perception is easy. Your CPU is mostly a serial processor, so logical reasoning is easy and perception is hard.

      • cratermoon an hour ago

        > Perception tasks involve relatively simple operations across very large amounts of data, which is very easy if you have a lot of parallel processors.

        Yes, relatively simple. Wait, isn't that exactly what the article explained was completely wrong-headed?

no_op 2 hours ago

I think Moravec's Paradox is often misapplied when considering LLMs vs. robotics. It's true that formal reasoning over unambiguous problem representations is easy and computationally cheap. Lisp machines were already doing this sort of thing in the '70s. But the kind of commonsense reasoning over ambiguous natural language that LLMs can do is not easy or computationally cheap. Many early AI researchers thought it would be — that it would just require a bit of elaboration on the formal reasoning stuff — but this was totally wrong.

So, it doesn't make sense to say that what LLMs do is Moravec-easy, and therefore can't be extrapolated to predict near-term progress on Moravec-hard problems like robotics. What LLMs do is, in fact, Moravec-hard. And we should expect that if we've got enough compute to make major progress on one Moravec-hard problem, there's a good chance we're closing in on having enough to make major progress on others.

jes5199 2 hours ago

I would love to see some numbers. How many orders of magnitude more complicated do we think embodiment is, compared to conversation? How much data do we need compared to what we’ve already collected?

Legend2440 3 hours ago

Honestly I'm tired of people who are more focused on 'debunking the hype' than figuring out how to make things work.

Yes, robotics is hard, and it's still hard despite big breakthroughs in other parts of AI like computer vision and NLP. But deep learning is still the most promising avenue for general-purpose robots, and it's hard to imagine a way to handle the open-ended complexity of the real world other than learning.

Just let them cook.

catgary 3 hours ago

Yeah, this was my general impression after a brief, disastrous stretch in robotics after my PhD. Hell, I work in animation now, which is a way easier problem since there are no physical constraints, and we still can’t solve a lot of the problems the OP brings up.

Even stuff like using video misses the point, because so much of our experience is via touch.

cratermoon 2 hours ago

It might be nice if the author qualified "most of the freely available data on the internet" with "whether or not it was copyrighted" or something to acknowledge the widespread theft of the works of millions.