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PhD Student gets quadrotor helicopter moving aggressively

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Re: PhD Student gets quadrotor helicopter moving aggressively

#41

Post by wwalker3 »

andreyf wrote: post #29
thaumaturgy wrote: post #5

Nice! This is more of what I'd like to see on HN.

Might be asking too much, but I'd also like to see a thread discussing the possible parts, schematics, and source code I could use to hack one of these together myself :) To start: what kind of rotors are those? Are they expensive?

It sounds like the control system is the expensive part. It uses a Vicon motion capture system to track the quadrotor using 20 cameras arranged around the room, plus custom control software running on a laptop, and an XBee wireless link from the laptop to the quadrotor to send the control signals.

The interesting part to me is the overshoot you see when the quadrotor shoots through the window, then pulls back nearer into a resting position. This implies that the control software can work out a dynamic trajectory (one where the quadrotor wouldn't be able to hover at every point along the trajectory), then reconcile it with a desired end point that won't fit onto the trajectory.

That sounds simple, but many walking robots still can't do that -- their gaits are designed so they could freeze in place at any time and still not fall over.

Re: PhD Student gets quadrotor helicopter moving aggressively

#42

Post by ajuc »

viraptor wrote: post #17
ajuc wrote: post #2

This is cool. But it looks like it has too many degrees of freedom to make such fast/complicated manoeuvres steered by human.

Isn't that thinking about the control on a very low level? Why do you need to know about the degrees of freedom -- if you're able to say exactly where you want the device to be, do you need any more details about the path? Sure - the fun factor of the complete control is gone, but the usability goes through the roof.

I just like to feel in control of machine, here it wouldn't be possible.

Besides - the more direct control is the more predictable behaviour of this vehicle can be.

I don't think every possible route between 2 points will be possible even using these vehicles. So steering this will probably look more like RTS - I pick control points, unit chooses the path.

This can cause some pain.

Re: PhD Student gets quadrotor helicopter moving aggressively

#43

Post by electromagnetic »

baddox wrote: post #21
chaostheory wrote: post #13

I'm sure the DOD would probably want a word with that guy

You don't think the DOD has tons of this stuff under its belt already?

If it doesn't already, it will do soon. 3 ... 2 ... 1 ... oh look, the guy just got a DOD research grant.

Re: PhD Student gets quadrotor helicopter moving aggressively

#44

Post by blhack »

starkfist wrote: post #39
dschobel wrote: post #37

Serious question, is there anything driving mobile robotics research besides the defense dept? I spent my grad school time in a robotics lab and it always bummed me out that anytime you see something amazing like this it's invariable funded by a military research agency which can't wait to strap a gun to the damned thing. Same thing for computer vision, except it was all about surveillance.

In the USA, no, not really.

So where is this different? And how? Who is funding this outside of the US and for what?

Re: PhD Student gets quadrotor helicopter moving aggressively

#45

Post by erik »

blhack wrote: post #44
starkfist wrote: post #39

Earlier quoted context omitted.

In the USA, no, not really.

So where is this different? And how? Who is funding this outside of the US and for what?

Apparently a lot of robotics work in Japan is aimed at assisting the elderly and making up for labor shortages.

Re: PhD Student gets quadrotor helicopter moving aggressively

#46

Post by starkfist »

blhack wrote: post #44
starkfist wrote: post #39

Earlier quoted context omitted.

In the USA, no, not really.

So where is this different? And how? Who is funding this outside of the US and for what?

The japanese do a lot of robot research and AFAIK most of it is not military.

I'm not sure if the non-military clause in their constitution means they can't do military research.

Re: PhD Student gets quadrotor helicopter moving aggressively

#47

Post by philwelch »

run4yourlives wrote: post #26
dpatru wrote: post #19

Earlier quoted context omitted.

This was my first thought. It's sad that whenever new technology is developed, governments think of ways to use the technology to kill people.

A simple look a history suggests that 99% of all human invention begins with looking for a better way of killing each other. Don't blame governments, we're all like that.

That's kind of a weird thing to say, since the main reason so many inventions are related to weapons is directly because political entities war with each other so much. Serial killers, cuckolded husbands, and street gangs don't usually pay for new weapons inventions the way governments do.

Re: PhD Student gets quadrotor helicopter moving aggressively

#48

Post by sp332 »

nitrogen wrote: post #27
volare wrote: post #23

Earlier quoted context omitted.

I do not dismiss this research: it is amazing. But, I also think you are underestimating the skill and sophistication of RC helicopter hobbyists. There are international competitions involving very complex, but well-defined and precise maneuvers. For example, there is a maneuver named "chaos" in which the pilot continuously pirouettes while continuously flipping while continuously rotating the axis of the flip while…

That was an amazing stunt. Has something like that been used as a plot device in an action movie yet?

There was a stunt at the end of the Italian Job (the new one, of course) where a stunt pilot actually flew a full-size helicopter around inside a parking garage. Can't find the clip right now, probably DMCA'd :-/

Re: PhD Student gets quadrotor helicopter moving aggressively

#49

Post by Natsu »

I wonder what the control system for that looks like?

I had a professor who engineered control systems and I remember him showing me this giant PDE-filled matrix that described the control system for the helicopter.

One of his grad students even had a computer simulation where you could try to fly a helicopter with no control system on it. It was pretty much impossible to control. Whenever you tried to go forward, you were likely to flip over.

Re: PhD Student gets quadrotor helicopter moving aggressively

#50

Post by HeyLaughingBoy »

slackenerny wrote: post #38
andreyf wrote: post #29

Earlier quoted context omitted.

Might be asking too much, but I'd also like to see a thread discussing the possible parts, schematics, and source code I could use to hack one of these together myself :) To start: what kind of rotors are those? Are they expensive?

$100 in parts, according to this guy: http://vicacopter.com I tried (unsuccessfully) to make his design a year ago and it was more like $300 though, and that assuming you have the RF equipment. Guy works at NASA I think. The claim that his is the only fully open source autopilot is to my knowledge true. No docs or schematics though, but these could be adapted from other projects, http://mikrokopter.de http://diydrone…

What about the Rotomotion guys? I thought their stuff was also released as OSS.
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