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Humanoid Robot Actuators

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Re: Humanoid Robot Actuators

#11

Post by Fraterkes »

Animats wrote: post #7

The power of money. I spent some time on legged locomotion back in the 1990s. It was clear then that you wanted torque control, and I did some work on the theory for that, trying to solve it from first principles, not machine learning. Got some nice theory and a patent out. But the parts just weren't there to build such things. As the article points out, the key to this is motor back-drivability. The final drive has…

Silly question maybe, but didn’t Boston Dynamics have videos of bipedal robots doing acrobatics / running ~7/8 years ago? Kinda looked like they “solved” locomotion then

Re: Humanoid Robot Actuators

#12

Post by Animats »

Fraterkes wrote: post #11
Animats wrote: post #7

The power of money. I spent some time on legged locomotion back in the 1990s. It was clear then that you wanted torque control, and I did some work on the theory for that, trying to solve it from first principles, not machine learning. Got some nice theory and a patent out. But the parts just weren't there to build such things. As the article points out, the key to this is motor back-drivability. The final drive has…

Silly question maybe, but didn’t Boston Dynamics have videos of bipedal robots doing acrobatics / running ~7/8 years ago? Kinda looked like they “solved” locomotion then

Their approach required pre-computation and simulation before execution. If you watch their videos carefully, you can see the advance planning work on some of the screens.

Re: Humanoid Robot Actuators

#13

Post by Fraterkes »

Animats wrote: post #12
Fraterkes wrote: post #11

Earlier quoted context omitted.

Silly question maybe, but didn’t Boston Dynamics have videos of bipedal robots doing acrobatics / running ~7/8 years ago? Kinda looked like they “solved” locomotion then

Their approach required pre-computation and simulation before execution. If you watch their videos carefully, you can see the advance planning work on some of the screens.

I can understand pre-computation making the “software” problem of locomotion easier, but how does it help with the hardware problems laid out in the article, ie repeated very high load over a very short amount of time?

Re: Humanoid Robot Actuators

#14

Post by Animats »

Fraterkes wrote: post #13
Animats wrote: post #12

Earlier quoted context omitted.

Their approach required pre-computation and simulation before execution. If you watch their videos carefully, you can see the advance planning work on some of the screens.

I can understand pre-computation making the “software” problem of locomotion easier, but how does it help with the hardware problems laid out in the article, ie repeated very high load over a very short amount of time?

BD used hydraulics for a long time. Works, but inefficient. You have to carry the actuators, the tank, probably a hydraulic accumulator, the pump, valves, and the power source for the pump. That's why BD's machines were so big. Someone at Google said "We need to have a conversation about hydraulics", and the dog robot in 2019 was the first all-electric machine.

Re: Humanoid Robot Actuators

#15

Post by rob74 »

elil17 wrote: post #10

I simply do not understand why you would ever prefer a fully humanoid robot as opposed to a humanoid torso on some other locomotion system.

Isaac Asimov already explained that better than I could (https://www.reddit.com/r/asimov/comments/pm84ud/why_robots_a...):

> Besides that, our entire technology is based on the human form. An automobile, for instance, has its controls so made as to be grasped and manipulated most easily by human hands and feet of a certain size and shape, attached to the body by limbs of a certain length and joints of a certain type. Even such simple objects as chairs and tables or knives and forks are designed to meet the requirements of human measurements and manner of working. It is easier to have robots imitate the human shape than to redesign radically the very philosophy of our tools.

Re: Humanoid Robot Actuators

#16

Post by zarzavat »

elil17 wrote: post #10

I simply do not understand why you would ever prefer a fully humanoid robot as opposed to a humanoid torso on some other locomotion system.

Presumably for outdoors or home deployment. The world is designed for bipedal locomotion, and human bipedal locomotion is designed for the world.

But yes, for a factory or commercial environment it doesn't make too much sense. It would be cheaper to adapt the environment, and many commercial environments are already designed to be accessible for wheelchair users anyway.

Re: Humanoid Robot Actuators

#17

Post by elil17 »

rob74 wrote: post #15
elil17 wrote: post #10

I simply do not understand why you would ever prefer a fully humanoid robot as opposed to a humanoid torso on some other locomotion system.

Isaac Asimov already explained that better than I could ( https://www.reddit.com/r/asimov/comments/pm84ud/why_robots_a... ): > Besides that, our entire technology is based on the human form. An automobile, for instance, has its controls so made as to be grasped and manipulated most easily by human hands and feet of a certain size and shape, attached to the body by limbs of a certain length and joints of a certain typ…

Right, but:

1. Asimov wrote that because he needed robots to be indistinguishable from humans for plot reasons.

2. We do 99% of our tool use with our arms and hands. We are already very good at building robot arms. We are getting better at robot hands. We can build robot legs, but they're very expensive and they pose a major safety risk for the robot itself and surrounding humans (because the robot can fall if there is a failure). For most applications, why not just put biomimetic hands and arms on a rolling base?

Of course, all this humanoid robotics research is still useful because if you can build a fully humanoid robot you can trivially build a torso-on-rolling-base robot. I sort of suspect that most of the humanoid robotics companies already know that the vast majority of their sales will be in that category.

Re: Humanoid Robot Actuators

#19

Post by ramon156 »

modeless wrote: post #5

AI was clearly heavily used in the making of this article, and I almost dismissed it as slop. But after reading it I think there's enough correct information here for it to be useful as a general overview of the problems in the space.

They should've left out figure 6. it adds very little and the screws are wrong.

Re: Humanoid Robot Actuators

#20

Post by raphman »

modeless wrote: post #5

AI was clearly heavily used in the making of this article, and I almost dismissed it as slop. But after reading it I think there's enough correct information here for it to be useful as a general overview of the problems in the space.

I believe that bad/wrong explanations are actually much worse than no explanations.

Many figures seem to be either missing key information (e.g. Fig. 5: the elliptical deformation is not shown - a human artist would have created a very different figure to explain the concept) or plain wrong (Fig. 6: the threaded rollers have the wrong orientation, Fig. 7: the ball is much too large for the bearing and the whole figure seems nonsensical at first glance).

And if the author did not spot these obvious problems with the figures, they either have no clue, accept sloppy work, or didn't even read the article they generated. That article is not really good advertising for the company's products.

(That the link behind the author's name leads to their Wikipedia article which seems to be a revised copy of the CV on their website is interesting, too.)

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