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DraganFly III Gyro-stabilized RC Helicopter
Pronoun54 writes "It hovers! It spins! It spies!
The Draganflyer III weighs just 17 ounces with its high-tech stabilization system. "As an eye in the sky, the Draganflyer III can be used indoors or out, up to a mile away, to take aerial views of real estate, promote products at trade shows, or give the guy in the next cube a close encounter he won't soon forget." "One more advantage of the Draganflyer III: if you're grounded by bad weather, you can still open the throttle and hover indoors." Their site has videos of this thing in action both indoors and out. Seems like it can move pretty fast at top speed." The Times has a piece talking about the piezo gyroscopes (including purty pictures) that the chopper uses to self-stabilize.
Their marketing people must be extremely happy!
Here's a project on sourceforge (GPL'ed):
autopilot
"It's too bad that stupidity isn't painful." - Anton LaVey
"hard to reach locations to make money on the side!" This has Jailbait written all over it!!!o:-)
Of course, you won't get the purty pictures:
: www.rctoys.com/draganflyer3.php+&hl=en&ie=UTF- 8
http://216.239.51.100/search?q=cache:Zcv7fU8bM28C
--
http://nemilar.net - Not your grandmother's soup kitchen
more importantly -- it needs re-chargin' every 5 minutes or so.
My life in the land of the rising sun.
if not, imagine all the places (other than the shower) you could put that X10 you bought while you were drunk! ... delay for reader to close popup ad....
wouldn't that be fun!?
MARIJUANA, SHROOMS, X: ONLINE?! - E
NiCd's tolerate high discharge rates better than NiMH batteries, and FAR better than Li-ion batteries. They can also be charged faster.
You can discharge a SCR NiCd battery in four minutes and not damage it. Do that to a NiMH battery, and it'll be too hot to touch, and will be damaged. Try to do that to a Li-ion battery, and you'll ruin it the very first time.
Also, the NiMH and Li-ion batteries have a higher internal resistance. Voltage drop == discharge rate * internal resistance, so as you draw more and more amps, you get fewer and fewer volts. Eventually, you get less total power from the NiMH and Li-ion batteries, even though they have higher capacities.
I doubt these things will fly for much longer than ten minutes (if even that.) You're discharging the batteries at a high rate, so you need batteries that can handle it. And those batteries are NiCd's.
Some park fliers can use Li-ion batteries, and they can stay up for 30-60 minutes at a time. But they fly very slowly and have very little power. Helicopters and other similar vehicles are not so efficient.
Don't forget the VIDEO
/ 20 020808_HOWW_helicopter/cir_HOWW_heli_05.html
http://www.nytimes.com/packages/html/technology
If you were to use NiMH or Li-ion batteries, you'd need much larger ones -- they'd be so large that it couldn't fly with the additional weight.
On the bright side, these NiCd's can probably be charged in 15 minutes. So, if you have four or five battery packs and a good charger, you should be able to keep flying with only short stops to swap out batteries -- the other battery packs will either be cooling or charging (charging hot batteries = bad idea -- great way to ruin them.)
I have been flying r/c gas-powered, gyro-stabilized helicopters for 8 years now. This is nothing new. Most people can buy a full fledged heli setup for $700 or so. Back about 5 years ago, solid state gyros (piezo gyros) came out and have made the old mechanical gyros seem slow and imprecise. For more info on "real" r/c helicopters here are some links:
. century.comh eli-world.comt aba-rc.com
.61 SX-H engine. Any questions, feel free to ask.
http://www.miniatureaircraftusa.com
http://www
http://www.heliproz.com
http://www.
http://runryder.com
http://www.fu
http://www.osengines.com
I fly an X-Cell Graphite 60 size helicopter with a futaba 9zhs (9 channel) computer radio controller, futaba gy601 piezo gyro, OS
Check out their Draganflyer X-Pro model.
Here's the google cache.
Only $4997! (no, I didn't miss a decimal point.)
X10 is probably already hard at work on the pop-up/pop-under ads for this...
"Good things don't end with eum, they end with mania or teria." - H. Simpson
Combine this with a fun GUI and we can chase osama out Afghanistan. So he hides in the tunnels eh? Just load up another GUI and down some
tunnels we go!
It's a marvelous device. The one thing I was really bummed about was that it only went 5 minutes on battery. That's a pretty big limitation if you think about it. Even 15 minutes would be a heck of a lot better.
And the robotics professor who tried controlling it by computer really only got it to fly up 15 centimeters and land without help. That was a bit disappointing, as I'd love to work on programming one of these puppies.
--LP
What's being claimed for the Draganflyer is claiming is that hovering is essentially taken care of by the onboard processors, and all a novice flyer has to learn to do is move the joysticks in the direction they want to go. Compared to flying a regular R/C helicopter, this is trivial to learn. With a R/C heli, you have to understand quite a lot about how the collective, the "ailerons", the main rotor pitch, and the tail rotor pitch all interact in order to learn to fly, and you certainly can't just point it in the direction you want it to go and expect it to go there. With the Draganflyer, you apparently can.
I had a similar craft called the "UFO", which was maybe 50% larger than this one, but exactly the same design. Four props, two counter-rotating, with fancy stabilization electronics.
I've flow planes, gliders, gas helicopters, electric helicopters, and mini helicopters, but this 4-bladed craft was harder than any of them.
The problem is with yaw stability. Any time I tried to do a fast straight flyby, the craft would slightly rotate (yaw) in the wind. It's exceedingly hard to visually see which leg is the "nose" and keep it forward.
That, and the flight times are abysmally low. The four motors weigh quite a bit, and use a huge amount of power to stay airborne.
That, with the difficulty in forward flight makes one prefer hovering, where power is used even faster.
All in all, a nice idea, but I threw mine out after crashing it repeatedly from disorientation. I even tried spraypainting the nose leg orange, no luck. It's that very slow sneaky rotation that gets the controls all goofed up.
A helicopter has a tail fin that helps orient it nose-to-the-wind in flight. This craft needs something like that before it can fly figure eights with the same ease.
I submitted this article almost two month ago when I saw it on Apple's website. Is this the normal turn around on articles? Soooooo Loooooooong.
The Black Widow (.pdf only, sorry) by AeroVironment doesn't hover but it's designed for just such a purpose.
I'd be happy to get either one for my birthday, thanks.
Others have already pointed out the open source Autopilot project.
The Draganflyer is limited to 5 minutes because it's so small and light, and runs on batteries. If you go with one of the more established conventional helis, you can get longer flight times. The longest times are still achieved by combustion engines, using either model fuel or regular gasoline, and it's quite easy to achieve more than 15 minutes with one of those.
However, I don't think it's any accident that the Draganflyer has an unconventional four-rotor design - this allows it to avoid many of the instabilities that a regular helicopter suffers from, and probably makes the job of programming an autopilot for it much easier.
Still, computer-controlled regular helis, even fully autonomous ones, are possible and have been done. There's even an annual International Aerial Robotics Contest. The site doesn't seem to be responding right now (secondary /. effect?), but here's one of the previous entries, the MIT/Draper Autonomous Helicopter Project.
In the past, these have been pretty expensive devices to put together. Nowadays, as the Draganflyer proves, it's not as expensive as it used to be. The piezo gyros are pretty cheap - in the $100 range for a decent one. Building your own computer-controlled helicopter is definitely doable. The Sourceforge project is probably a good place to start, especially since it'll be a lot easier if it's not a one-man project.
Crashing is a part of the learning experience. What many of us did is we take two long dowel and make an "X" out of them and attach it to the bottom of the heli. THis gives in a big footprint so if one was to come down the wrong way, the heli won't tip.
c ts&cat=20
Given the FMA co-pilot and heading hold gyro, the heli can fly on its owwn almost.
link to FMA co-pilot: https://www.fmadirect.com/site/fma.htm?body=Produ
Yeah, way to totally avoid the point. In real life, there's usually wind, which your X-Cell can't deal with without inputs. I'll rephrase. Would you hand your controls over to a random passer-by with no flight experience, to try out? No? Didn't think so. That's why the Draganflyer is something new, because you can actually do that.
Pretty cool video... but since it doesn't have sound, you *really* need to insert "Flight of the Valkyries" on the audio track. :-)
~Philly
Aerial surveillance and photography and stuff would be a neat little hobby
Not with this. It only flies for five minutes. What you need for longer flight times is an RC Airship. They can fly for quite a bit longer as the gas does the lifting, and the battery just powers steering. The cost is in the thousands of US dollars however.
Yes. I've also written code to do stabilization on a Scenix microprocessor.
I wasn't trying to say that the Draganflyer guys invented the idea of stabilization, but the fact is that most R/C helis today have no such technology.
In case you're just not understanding what the DraganFlyer does, you can think of it like your heading-hold gyro, but applied to more dimensions. It uses piezo gyros in multiple dimensions, in a similar way to what the FMA Copilot does using infrared differential.
In addition to that, the DraganFlyer's four rotor design and computerized control mechanism means that flying is intuitive - you don't have to deal with collective, pitch, etc. to make it fly, the computer translates the direction you want to go into the appropriate instructions for the aircraft.
In short, it seems you just haven't yet understood what the Draganflyer does. Hope I've cleared it up a bit for you.
The Vectron Flying Saucer is insanely fun and less than $100.
:-)
Check out this Tech TV article.
I bought one recently and my only regret is not letting the Vectron have it's recommended cool-down breaks. I was having too much fun and the constant use killed it in one weekend.
If you don't have vaulted ceilings, get some.
I know it's redundant, but just imagine the marketing potential if this thig gets bundled with X10 cameras.
"See what you've been missing in your nieghbor's second story bedroom"
T Money
World Domination with a plastic spoon since 1984
And there is one for Linux: the autopilot simulator. It's GPLed and easier to extend for your hacking projects. I'm using to help tune our helicopter autopilot, which is also available under the GPL. Unlike the DragonFlyer, our rev 2.2 IMU (also GPLed) is a full inertial guidance system with GPS interface.
-- http://www.swcp.com/~hudson/
This is gonna do to the haircutting business what McDonalds has done to dinner.
Bulk discounts at stadiums are the wave of the future.
Table-ized A.I.
you mean "Who's the moron now?!?" I think.
Moron.
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
It depends on what type of rc maybe. At least in the car world NiMH rule the world. 3000 milli-amp sanyo 3000 HV are pretty much the top of line. Even where you can get NiMH and NiCD overlap (2400 milli-amp) to NiMH are the ones used. They have more "punch" and thier voltage discharge curve is better. When racing rc cars the NiCD tend the drop quickly at the beginning, then drop at a fairly even rate for the rest of the battery. Whereas NiMH drop off early but level off (same speed as the top end of the NiCD). They only dump right at the end of thier charge.
And I would have to say I use some fairly hefty draw. the standard tamiya plugs (basically the tube type connectors - not sure their technical name) will melt and fuse the metal together. I either have to directly solder everything or use "zero resitence" plugs (the resistence is less than the equivilent length of wire - so they use some marketing crap) such as deans ultra plugs. For the 10'th scale rc cars some of the modified engines will drain a 3000 milliamp NiMH in around 5 minutes. If your taking more draw that a 9 turn single hand wound 540 engine in a small rc then you must be making it yourself.
For lightweight motors look at something like a speed 280 bb - runs aprox 4000rpm/volt. I can run them in my HPI micro rs4 and get ~30000 rpm at the shaft (same as my larger stock engine for the 10'th scale touring car). I run it from a 6 sub aa 1100 pack and get ~15 mins runtime.
I dunno, maybe in other types of rc this is not the case but for the extremely high draw engines only the NiMH are used - NiCD does not have the performance in a 10'th or 12'th scale vehicle.
FYI I got my matched set of sanyo's out - the tag says 369 sec @ 1.143 volt - 30 amp - 3.2 mOhm internal. In rc car land matched batteries are batteries that someone (in this case team orion - or whoever they paid to do it) fully charges the batteries. They are next placed on a discharge tray and are given a draw of 30 amps. Things such as discharge time and internal resitence are checked and then the batteries are "matched" to all have fairly equal settings. They are sold in grades - the longest running/lowest resitence seel the highest with the sucky ones going into unmatched packs (eg radio shack specials). I do not have an older set of matched NiCD's to look at - but the NiMH perform much better here.
------- Sorry about the spelling, I suffer from two problems. Dyslexia makes it difficult to spell well, lazy makes it
Or, perhaps you need to read the given links.
:-)
Draganfly comes from the inventor's name, Zenon Dragan.
Clever, eh?
regards,
MAJ
-Better it is to be thought of as a moron, than to type and remove all doubt.-
NiMH offers higher capacity for a given size/weight. But the internal resistance is higher, and they will not tolerate the high discharge rates that NiCd's will. Here's a reference for you. Cars and planes have similar requirements, but planes are far more vulnerable to increased weight, so you'll find that high performance planes often only have enough capacity to fly for a few minutes -- they use the bare minimum capacity to keep weight down. And since they need to dump their charge in 3 minutes, they need NiCd's.
Matched packs have been around for a long time, and the procedures for making them have not changed since NiMH became popular. The idea is to have all your cells go dead at the same time -- otherwise 1) you've got extra, unused capacity at the end of your race, capacity that could have given you more speed and 2) if one cell goes dead first, the other reverse charge it, making it even weaker, and eventually ruining it.
In your case, if a good NiMH cell can do 30 amps, a good NiCd cell of the same size may be able to do 60 amps delivering the same voltage. It all depends on what you're looking for. If you want to dump all your power *very* quickly, you want NiCd. If you want to do it slower, NiMH may be what you want. And if you've got an hour to do it, Li-ion works well.
After all, there's a reason rechargable power tools and similar items usually use NiCd's -- the same sized battery can deliver more current at the same voltage.
Btw, the reason that NiMh batteries are taking over isn't just the higher capacity -- the main reason is that NiCd batteries are unfriendly to the environment, so they're being `phased' out.
I have planes that use NiCd cells, and planes that use NiMH cells. The NiCd planes are usually high performance, short flights, and the NiMH planes are usually lower performance but fly longer.
I've also got a few R/C cars, and so far, all my batteries for those are NiCd. NiCd's may give me a shorter run, but they also give me more power. It's all a tradeoff ...
You could have a 'helipad' bolted to your window-ledge, you program it as home (by GPS),
I hope you help assist it in landing. My GPS us usualy acurate within 20 feet most of the time in the horizontal plane and 50 feet verticaly. It would need to be a big landing pad to avoid broken windows.
The truth shall set you free!
I bought one in early 1999.
Build stuff. Stuff that walks, stuff that rolls, whatever.
Piezo gyros are almost standard now for yaw stability on regular helis, but the ones now available for regular helis to better than the ones on the Draganflyer. Regular helis use a "flybar" in the rotor head that does the same thing the as the other two piezo elements on the Draganflyer - but, again, they do it better. The Draganflyer hovers with about the same difficulty as a regular heli - the feel isn't even much different - but once you get moving faster than a crawl, it becomes a real handful. Regular helis are actually much easier to control when flying with any speed. Regular RC helis also have aerobatic potential that fixed-pitch machines like the Draganflyer can't even come close to.
It's not a bad way to get the hand-eye coordination for hovering, but if (when) you want to get it flying around or get into aerobatics, you'll need something else entirely. And if you're looking for a way to get started with RC helis, a PC simulator is a much better investment.
Build stuff. Stuff that walks, stuff that rolls, whatever.
Some friends and I put gyros on a flybarless heli once, just to see what would happen, and while they tame down the bad behaviors, they don't help nearly as much as a flybar. The Draganflyer (fak Roswell Flyer) feels about as bad as a flybarless heli, and probably for the same reasons (no flybar on the Roswell, just wacky rotor flapping due to disymmetry of list). I'd prefer a flybar-equipped rotor over flybarless any day, and the (flybarless) Roswell Flyer / Draganflyer is no exception.
In short, it seems you just haven't yet understood what the Draganflyer does.
Seems to me he knows exactly what the score is. I've flown one. Have you?
Build stuff. Stuff that walks, stuff that rolls, whatever.
I added a vertical stabilizer to my Roswell (Draganflyer = Roswell Flyer v2.0, same electronics on a more robust chassis). The fin did help keep it pointed forward, but then the problem is the pitch & roll response. It turns out that a platform with four flybarless rotors fly just as bad as a heli with a single flybarless rotor. It's really hard to describe, but if you've flown a flybarless heli, you know what I'm talking about.
These are OK for indoor flying where you never build up much speed, but beyond that they're a real handful.
Build stuff. Stuff that walks, stuff that rolls, whatever.
Flight times: They all get about 10-15 minutes on a tank of fuel, as the other fellow said. The control system battery needs to be recharged every 4-6 flights. Eletrics typically fly 4-6 minutes on a charge, but flight times and performance are getting better all the time for those things (I'm hoping to switch to electric when they can make good power for 10 minute flights, but it will probably be a couple years at least). Gasoline powered helis (only available in the larger size, around 12 pounds) run for 25-45 minutes on a tank of fuel, but they don't have quite the same power-to-weight ratio as alcohol burners. Alcohol helis are more popular for aerobatics. Gassers are popular for aerial photography because they have almost no exhaust trail, and for everyday flyers who aren't as concerned with aerobatics and who enjoy cheap fuel (alcohol is $12-25/gallon depending on various factors including the nitro content).
Cameras: I put a video camera and wireless video transmitter on a couple of mine, with the intention of recording aerobatics from the 'pilots' point of view. There are small cameras that work pretty well for this, the handling of the helicopter was unchanged. Unfortunately, the video range you get with FCC-license-free video transmitters is not very good. It works well for upright flight, but the signal drops out a lot during aerobatics.
Click here for one of my videos. I made this one to demonstrate the video drop-out problem, so it's pretty bad. I had a couple others that (by pure luck) had better reception, but unfortunately I don't have copies online on a server that can take a slashdotting.
I got a ham license a couple summers ago specifically so I could get some more powerful transmitters for wireless video, but I haven't upgraded the video transmitter yet. It's still something I want to do, though. I'll get around to it eventually.
Build stuff. Stuff that walks, stuff that rolls, whatever.
I know nothing about full-size helis, but the PC simulators available for RC heli practice are spectacularly useful. I pity people who learn without them. It's possible of course, but simulators make it so much easier it's almost like cheating. Even all the way into complex aerobatics... I still practice stuff on the simulator all the time before I do it out at the field.
Most of the commercial RC heli simulators cost $200ish, but it's money well spent. That's the cost of a couple crashes with the model, and a sim will save you from way more than just two crashes. I highly recommend a sim to anyone getting into RC helis.
Build stuff. Stuff that walks, stuff that rolls, whatever.