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Comment by zacharydanger | Hacker News Reader

I couldn't figure out how the quadrocopters were coordinated. Turns out it's a high-speed motion capture. More here: http://www.flyingmachinearena.org/

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I've ranted on this topic before [1]. I still think it's a bit dishonest... academics shouldn't promote their work to general audiences without properly denoting caveats. In this case... they're using a ~$50k vicon motion capture system that returns millimeter-precision pose estimates at ~1kHz.

[1] http://www.hizook.com/blog/2012/07/02/being-honest-robot-vid...

Without the vicon and (probably) a central control PC, this feat would be SUPER difficult -- by ~1-2 orders of magnitude. The real problem is: when someone does solve that herculean problem, the general public won't care. They'll just say, "eh, we've seen that before."

Who cares what the public thinks? The funding and eventual commercialization will come from people who do understand what is going on here.

I'm no expert, but I would imagine that research using remote viewing and centralized processing is just a first step that could make it easier to validate particular solutions, which can then be "baked into" self-contained platforms.

It's the same as industry... good PR goes a long way toward acquiring funding. Would you be upset if (say) Apple, Google, or Microsoft's PR machine was intentionally deceiving folks? Academics are even more sensitive to this -- it's why we're always railing against "shitty science reporting."

Also, I suggest reading the article. I am an expert... I greatly admire this group's research(!!), which is why I don't mind giving 'em some tough love. But I also want the group that "cracks the egg" for self-localization and decentralized control to get their deserved limelight. This video makes that less likely.... as evidenced by the fact that so few people in this thread (probably) know what a Vicon is, how it works, or that it's being used.

What if they demo it in a non-laboratory setting, especially one where noisy backgrounds would make vicon impossibly difficult. If I understand correctly, the main problem with vicon is that it can't really be used in a real world scenario, right? So if the demo shows what can be done with the non-vicon solution, it should still be effective.

To first order, this is always true. It should also be noted that computation happens on a desktop computer.

For quadrotors at least. Most of the projects I've seen coming out of Boston Dynamics are, as best I can tell, entirely self-contained.

(This is part of why BD impresses me so much)

I may not be fully up to date but I have never seen a BD video with cooperating robots.

Yes, but none of them are (permanently) aerial and some of them use internal combustion for power. Computation requires weight and energy, and computer vision requires lots of computation.

Aren't most of their videos using a tether though? Which is pretty much the same "only works in the lab" issue.

Projects using quadrotors to do things like fly cooperatively and do acrobatics [1,2] will often use high speed motion capture systems with multiple fixed cameras. This decouples the problem of perceiving the environment from the problem of responding to the environment.

More broadly in robotics there are plenty of people working on ground-based robots that don't rely on multiple fixed high speed cameras - self-driving cars [3] would be one example. There are also people working on cooperative ground based robots that don't rely on multiple fixed high speed cameras - for example, the RoboCupSoccer Middle-Size League [4]. There are also people working on quadrotors that don't cooperate/do acrobatics and who don't rely on fixed vision systems - for example people working on autonomous quadrotor mapping [5] and using IMUs and on-robot vision [6].

[1] http://www.youtube.com/watch?v=MvRTALJp8DM

[2] http://www.youtube.com/watch?v=wuSqwb13iw0

[3] http://www.youtube.com/watch?v=uoiJeIb0wBA

[4] http://www.youtube.com/watch?v=cXSGTkI390w

[5] http://www.youtube.com/watch?v=WoMrPKCpWXw

[6] http://www.youtube.com/watch?v=QKGZcTFambE

Yeah, kind of restricts to the lab, unfortunately, although a secondary camera drone meshed with the others might serve. Lighting would be a problem... though they could use IR beacons or something.

Lasers wouldn't have that issue. And make this even cooler.

Lasers are typically directional.

That must be the purpose of the spherical marker-balls on the "pendulum" (looks like a rod???), two of them dividing it into three segments. I wondered what they were for, I'm guessing they help with the motion capture/tracking.

Maybe, but they could also be used to fine-tune the rod's moment of inertia.

They probably use them to track the center of gravity of the rod while in flight.

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