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MIT cheetah robot lands the running jump [video]

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Re: MIT cheetah robot lands the running jump [video]

#151
post #31

No one seems to be discussing how this can be improved! Here are a few points: 1. Real cheetahs don't run like that. The action of both pairs of legs is staggered for smoother motion and control. Check this out - https://www.youtube.com/watch?v=131wvVGjZUc 2. Looking at this jumping-over-obstacles video, it seems like the robot is lacking flexibility. The real life cheetah's hind legs go quite a bit underneath in pre…

I think it's safe to assume that the researchers have watched hours and hours of footage of cheetahs running - I'm sure they're aware the ways in which their work is not like the real thing. Watching some of the cheetah videos, I wonder how much of their staggering is compensation. That is, the "ideal" cheetah gait may actually be non-staggered. But as the cheetah is changing direction, dealing with slightly uneven g…

We can't possibly know what the researchers have actually done in their study but I think it's safe to say that symmetrical action is a lot easier to wrap your head around (it essentially becomes a 2D problem). That's why a staggered action should be seen as an improvement to the already existing design.

When it comes to cheetahs, I bet a million bucks that it has everything to do with impact and smoothness rather than a compensation for changing direction and such. My confidence in this comes from my own experience imitating animal movement in parkour. For an example of one person running in a staggered way - https://www.youtube.com/watch?v=W8oh5Xuy7NA. Running like that is MUCH easier on the joints than running with a symmetrical action. If you make a human gallop in a symmetrical way they'd quickly give it up for staggered action, regardless of surface or directions.

Re: MIT cheetah robot lands the running jump [video]

#152
post #46
post #31

No one seems to be discussing how this can be improved! Here are a few points: 1. Real cheetahs don't run like that. The action of both pairs of legs is staggered for smoother motion and control. Check this out - https://www.youtube.com/watch?v=131wvVGjZUc 2. Looking at this jumping-over-obstacles video, it seems like the robot is lacking flexibility. The real life cheetah's hind legs go quite a bit underneath in pre…

1.The goal is not to build a cheetah, buy to learn from them. One thing to consider is that this team is constrained by materials. What works for an animal will likel not transfer directly due to the difference in materials. Harmonics are well absorbed by tissue but the robot may have issues with them. 2. How did you come to this conclusion? Have you built a robot that mimics an animal? If so, may you provide some in…

I also forgot to point out that their robot is capable of running in a staggered manner [1] and the results are much cleaner than non-staggered action [2]. You can practically feel the second robot nearly tear itself apart even at lower speeds.

[1]: https://www.youtube.com/watch?v=1TXOHAVuS5Q&t=65

[2]: https://www.youtube.com/watch?v=chPanW0QWhA

Re: MIT cheetah robot lands the running jump [video]

#156
post #128

Earlier quoted context omitted.

I thought the whole point of Asimov's exploration of his three laws was that they were fundamentally insufficient for any real ethical security.

I think the only interaction most people have with Asimov's laws is just reading them and thinking they seem reasonable. If people actually read the stories they'd learn that the robots are constantly put into situations that pose exceptions to the laws or force the robots to make decisions that fundamentally break them.

I liked the story with the robot on Mercury running in circles, because it couldn't go closer to a lake from which it was tasked with taking a sample without being destroyed by the heat, but couldn't go back, because it would mean disobeying a direct command. Of course, a longer inference chain would show that not going back would lead to the people at the base dying, but you have to cut it somewhere, because if you let a robot indefinitely extrapolate possible actions, the only rational thing for it to do would be to self-terminate, since breaking the third law with certainty is obviously preferable than the infinitely many possibilities of infinitely many times breaking the first and second laws.

Re: MIT cheetah robot lands the running jump [video]

#157
post #24

Earlier quoted context omitted.

using something that's ground-based to impose control? I think we have that, they're called soldiers.

Which leads to the appeal of a mechanized infantry that never gets tired, never gets sick, kills without remorse, follows orders invariantly, doesn't eat or drink, has an upgrade path but most importantly can't be killed only destroyed or broken. Sure the first generation won't replace all soldiers and they may never replace them all. We will need logistics and support people of course. Its not a perfect solution. Bu…

We already have perfect soldiers that are "ever courageous, never sleep, never miss", but land mines are outlawed in most situations.

Re: MIT cheetah robot lands the running jump [video]

#158
post #88

Stuart Russel of AI a Modern Approach fame ( with Norvig ) asks us to consider the ethics of AI research - killer robotics, & hunter drones. http://www.nature.com/news/robotics-ethics-of-artificial-int... He calls for a moritorium until we can get a neural net to learn Asimov's 1st Law. Should the self driving car swerve into you to avoid greater moral hazard ? Humour aside as researchers and robotocists do we have a…

How about "the car slams on the breaks and swerves towards the more distant object". That's a simple algorithm with no morality issues. In general, building morality into machines is a very perilous proposition.

Re: MIT cheetah robot lands the running jump [video]

#159

So they can spend millions developing the robot, but the best they can do for tracking while they film from the side is a guy pushing another guy in a big plastic box on wheels. Way to go geeks!

They likely didn't spend millions, but got (hardware for) the robot for free from Boston Dynamics.

Re: MIT cheetah robot lands the running jump [video]

#160
post #151

Earlier quoted context omitted.

I think it's safe to assume that the researchers have watched hours and hours of footage of cheetahs running - I'm sure they're aware the ways in which their work is not like the real thing. Watching some of the cheetah videos, I wonder how much of their staggering is compensation. That is, the "ideal" cheetah gait may actually be non-staggered. But as the cheetah is changing direction, dealing with slightly uneven g…

We can't possibly know what the researchers have actually done in their study but I think it's safe to say that symmetrical action is a lot easier to wrap your head around (it essentially becomes a 2D problem). That's why a staggered action should be seen as an improvement to the already existing design. When it comes to cheetahs, I bet a million bucks that it has everything to do with impact and smoothness rather th…

You may be correct, but I wouldn't extrapolate from humans. We evolved to walk upright, so running on all fours is not something our structure will be good at.
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