Learning athletic humanoid tennis skills from imperfect human motion data

3/15/2026 at 9:15:27 PM

We have just started ramping up practical use of imitation learning from human demonstrations in humanoids. A bigger development is that one or two projects are working on training foundational vision action language models based on large video datasets.

I think before the end of summer general purpose physical knowledge and capabilities will start to be demonstrated by one or more humanoid AI or robotics groups.

Maybe 18 months at the absolute latest.

I'm guessing by next year or 2028 there will be services where you can order a robot to come cook and or clean for you. By 2029 it should be quite affordable to get a humanoid on a short term rental.

Do we have any standard benchmarks for humanoids to do domestic tasks?

by ilaksh

3/15/2026 at 9:21:22 PM

That seems like quite an extrapolation and an extraordinary statement. This is a single task, in a lab setting. What your describing are extremely open-ended tasks in people’s homes.

What is informing these timelines?

by mplappert

3/15/2026 at 10:30:24 PM

Look at recent developments/announcements involving novel increasingly generalizable learning capabilities from projects like 1X/Neo, Figure 03, Skild AI. Also see open published work like MimicDroid, HDMI, GenMimic, Humanoid-Union Dataset, RoboMirror, Being-H0

Figure 03:

https://www.youtube.com/watch?v=e-31-KBBuXM

https://www.youtube.com/watch?v=ZUTzuhkDG3w

1X Neo:

https://www.youtube.com/watch?v=lS_z60kjVEk

Skild AI

https://www.youtube.com/watch?v=YRmjBdKKLsc (Learning by Watching Human Videos)

by ilaksh

3/16/2026 at 10:45:36 AM

Yeah those are demos. I think we‘re pretty far away from this becoming a real thing. I wrote up why here: https://matthiasplappert.com/blog/2026/humanoid-robot-in-the...

by mplappert

3/16/2026 at 2:58:21 PM

You're not really trying to see the advances in things like the data flywheel. If you were you would see that those demos represent real movement towards generality.

by ilaksh

3/16/2026 at 5:07:26 PM

Where’s the data flywheel exactly?

by mplappert

3/15/2026 at 10:37:53 PM

" Do we have any standard benchmarks for humanoids to do domestic tasks?" The answer is yes. Steve Wozniak proposed the Coffee Test. See https://www.youtube.com/watch?v=MowergwQR5Y

It's actually very clever. Despite the apparent simplicity, no current model could pass it.

Re your forecasts, I think they are optimistic in terms of timing but not ridiculously so.

by nmaley

3/16/2026 at 2:52:27 AM

I think coffee test for robots will be similar to Turing Test for LLMs, which was quietly achieved and forgotten somewhere between gpt-3.5 and gpt-4. Real tests are tasks like cooking or plumbing - I expect that to come in 2-3 years.

by p1esk

3/16/2026 at 12:10:57 AM

The "AGI" (-ish) moment for AI was shoving Common Crawl into a transformer.

What's the animal intelligence (physical int.) equivalent of that? I don't think such a dataset exists? (e.g. NVidia is trying to compensate for that with simulated worlds, i.e. synthetic data)

by andai

3/16/2026 at 7:17:29 AM

Hey guys I rooted my humanoid and it killed my mom when I disabled the "slow limb motion" mode. It just wacked her in the head as she walked in the kitchen and she's not moving what do I do??

by vasco

3/16/2026 at 11:29:01 AM

You should @linustechtips and hope he picks it up, then you have a good chance of getting a voucher for the funeral and getting a shout out in the manufacturers next demo when they talk about their new safety features.

by SiempreViernes

3/15/2026 at 11:06:22 PM

I think that's a bit too optimistic, but I still think the direction is right-ish. It feels hard to give a timeline though. Robotics is hard.

by impossiblefork

3/16/2026 at 8:09:39 AM

>I'm guessing by next year or 2028 there will be services where you can order a robot to come cook and or clean for you.

Bullshit.

by auggierose

3/15/2026 at 9:20:45 PM

omg Elon Musk posts here! Are we also going to get full self driving, no interventions from NYC to LA within this timeframe, sir???

by ohyoutravel

3/16/2026 at 2:45:15 AM

I’ve been thinking about this too, and I share your optimism: https://news.ycombinator.com/item?id=47213310

by p1esk

3/15/2026 at 7:09:04 PM

It is interesting to watch. The movements of the robot are robot-like. I mean, wtf, there were no robot playing tennis before, but I have an idea how a robot playing tennis would be like, and this video confirms my expectations. Sharp, unsure movements, a lot of hesitation, ...

Movies pictured robots like this long before this become possible, but how did producers guessed it?

Or maybe movies rendered different kinds of robots, but this video bring into my memory only those, that look like this. A kind of confirmation bias?

by ordu

3/16/2026 at 10:40:13 AM

Also, I can't help noticing that the guy(s) playing with the robot are doing their utmost to make it look good: playing the ball as gently as possible (so it has time to react and doesn't have to exert too much force to return it), aiming for places the robot can comfortably get to etc.

by rob74

3/15/2026 at 10:26:46 PM

I agree that the movements look quite robotic (though not as much as you might expect), but I don't think any movies have depicted robots moving like that. A much more common depiction is moving only a single joint at a time.

> Sharp, unsure movements, a lot of hesitation, ...

I like these particular descriptors. Another I would add is holding poses unnaturally still. While waiting for the ball, the robot holds its racket extremely consistently relative to its body even while sharply turning.

by thethirdone

3/15/2026 at 6:28:36 PM

Nothing constructive to say, besides that the video really shows we're entering into a Sci-fi era.

by KolmogorovComp

3/15/2026 at 8:27:11 PM

Very impressive. But it doesn’t solve the whole problem yet.

The robot and ball pose is estimated by high speed mocap cameras, and is fed to the policy.

I imagine estimating that with onboard cameras - how humans do it - is much harder.

Almost all of closed loop robotics is a state estimation problem. Control is “solved” if you can estimate state well enough.

by blueblisters

3/15/2026 at 8:31:25 PM

We know. Just appreciate it for what it is. Which is…awesome.

by ohyoutravel

3/16/2026 at 11:31:59 AM

Look at the guys above posting that within 18 months these sorts of robots will be able to cook in anyone’s home; the above reminder is very necessary.

by SiempreViernes

3/16/2026 at 6:04:50 AM

I agree it is pretty awesome!

by blueblisters

3/15/2026 at 9:00:16 PM

This is so interesting. Especially since it's kinda weird to train a robot to mimicking human play. I wonder what a perfect robot what actually behave like.

It wouldn't need to split-step to activate muscles, the footwork would probably be minimal. I imagine a lot of different unusual looking swings to confuse human players, while still making perfect contact. It could make really late drop shots or even rotate the racket at the last moment for crazy angles.

Would love to watch this.

by V__

3/16/2026 at 5:53:47 AM

The humans in the video shot easy balls to the robot, which returns more difficult balls. It's the human that is doing all the running. The robot is quite static. However with better software and better hardware is possible that the robot will be so fast that it will miss no ball, and so strong to return balls faster than any human can reach. So there is no need to play fine shots. That could be a goal if we want to provide automated training partners to humans. If we want to win games against humans, stronger and faster is more than enough.

by pmontra

3/16/2026 at 7:19:38 AM

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by vasco

3/15/2026 at 10:39:17 PM

> I wonder what a perfect robot what actually behave like.

Really depends what its hardware is. One with hardware a lot like a human would behave like a human.

Since you didn't specify, I'm going to go with a robot that looks like a giant pong paddle.

by kadoban

3/16/2026 at 11:35:41 AM

I don't know much about tennis, but the perfect opponent is probably some form of slightly concave wall that will always bounce the ball into the court no matter the angle you send the ball at it

by SiempreViernes

3/15/2026 at 8:38:59 PM

Impressive! Looks like a nice alternative or evolutionary step for a ball machine. Either way, teach it to serve :)

by hbcondo714

3/15/2026 at 7:05:57 PM

Really impressive. In a few years there will be robotic AI instructors for the wealthy and their kids

by Aboutplants

3/15/2026 at 8:02:16 PM

Maybe for novelty, but the rich usually just pay humans to act like robots.

by squibonpig

3/15/2026 at 10:45:27 PM

Ironically something like this could eventually make elite level tennis training cheaper and more accessible. Families of some top US juniors already spend $100k per year, much of that on 1:1 coaching. Some fraction could eventually be automated, at least for repetitive basic skills practice. Like the next level of a tennis ball machine.

by nradov

3/16/2026 at 12:51:39 AM

human instructors for wealthy, robotic AI for the rest of us

by dandaka

3/16/2026 at 3:08:34 AM

So this is all pretty much theoretical, but very tightly woven strictly bounded protocols to be brought to production-- perhaps an accelerated alternative to perceive a much sooner ETA of 18months...

Maybe its moreso about reaching out to the right people about this "white paper" worthy research.

AFAIK, billions of dollars are poured into tennis mechanics at the highest level.

Introduce this to the right group of people, I truly can see this funded to play Janik Sinner where he would pay as a service to play against his worst nightmare.

by sam1r

3/15/2026 at 6:56:10 PM

This just makes me want to play tennis right now. Such an addictive sports.

by Void_

3/15/2026 at 7:14:16 PM

Why can some Temu humanoid robot do this sort of impressive, coordinated, high-speed thing, but Tesla Optimus completely sucks at everything unless they’re moving at 0.02m/s (and even then they’re not great)? Like, train this thing on the latent space of folding my clothes out of the dryer and I will send you my money.

by ohyoutravel

3/15/2026 at 7:50:24 PM

Relax, it is one demo. It probably can't handle the millions of edge cases that exist in real life.

by 10xDev

3/15/2026 at 7:52:55 PM

I’d be OK (and from a product perspective think it would be a win) if Optimus just mastered one high-value skill like clothes folding. Yet, here we are.

by ohyoutravel

3/16/2026 at 12:33:30 AM

Now we intellectual workers can race physical workers to see who becomes obsolete first!

by kace91

3/16/2026 at 3:51:48 AM

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by stainlu

3/16/2026 at 5:02:40 AM

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by useftmly