Robotic Helicopter

Larry Sutherland

First· apology due for first posting a question for ideas in Completed Projects.

I've completed "What's a Microcontroller",· "Robotics with Boe Bot·", (with Ping and GPS), and currently working through "....Toddler".

Reading Completed Projects Forum and I'm very inspired with all the good projects and great minds.

I am looking for some ideas, suggestions,· and other info for Robotic Helicopter.

Again my apologies too the Completed Projects Forum.

L Sutherland, Phoenix AZ··

Steve Joblin

That is quite a tall order... seems like most of what has been done to date is at Universities and such... I haven't seen too many "non-pros" with autonomous choppers.

Franklin

The first thing I can see that needs to be done is to acheive stable level flight. Use the same ideas used for the balancing robots.

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- Stephen

Larry Sutherland

I agree! I was looking at those helicopters at Frys Electronics and hacking it.

Beau Schwabe

Larry,

The mechanism used for auto balance on those helicopters is Very! slick ... by devoting more blade pitch to the lowest side ; less blade pitch to the highest side ; thus keeping the unit stable ....
And their fun to fly too! (until they meet their fate with a ceiling fan) <--- OopS .... The event knocked one of the balance weights off of the gyro. I was able to repair it, but it was never quite the same.

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

LoopyByteloose

Newer small R/C helicopters are like musical instruments - some are very expensive and easy to use; others are cheap and quite difficult. The cheaper ones have gotten a lot better recently, but I suspect they are not so good for robotic control.

If you want automated flight, might I suggest that you find a good helicopter you like and learn to fly it well?

I bought one of the cheaper ones last year just to try out and it tended to bounce off buildings and cars everywhere. Crosswinds will send it suddenly veering off in unexpected directions. The good ones [noparse][[/noparse]and expensive] have gyros which make flight under gusty winds and complex flight quite easy.· After all, the whole idea is to be able to hover over one spot when you want to.· Otherwise, you might as well use winged flight.

In other words, electric [noparse][[/noparse]or even gas] R/C helicopters generally will require an investment of some bucks to get rewarding results. In my case, I used the cheap $60 'copter for a week and gave it to a friend and his son that used it for a similar amount of time.· Everyone was happy with the experiment, but we all agreed that we had to have something better to really log a lot of hours.

For a first helicopter, you might find someone in a club·that is trying to upgrade from a trainer to higher performance. I'd much rather put my dings from learning into a 2nd hand machine than a brand new one.· It wouldn't hurt to have a mentor too.

Jens Altenburg won a prize in a·Parallax SX contest with a semi-automated flight controller that will give you a lot of useful ideas. Parallax has documented the project. He was able to detect horizon under a wide variety of conditions using two thermopiles as sensors [noparse][[/noparse]day and night; summer and winter]. Sparkfun also has altimeters that would contribute a lot to a useful design as once you are high enough, you have a lot more freedom to manuver.

There are Futaba gyros already available that integrate with all the controls in small R/C helicopters.· I wouldn't try to intergrate my own as it might slow·development way down. ·Eventually, I imagine you can use GPS to follow a preprogrammed flight plan or fly stunt sequences within a 'safe zone'.

I'd love to do ariel photography from one.· There is nothing quite as picturesque as a bird's eye view.

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PLEASE CONSIDER the following:

Do you want a quickly operational black box solution or the knowledge included therein?······

···················· Tropically,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Post Edited (Kramer) : 11/11/2007 4:19:38 PM GMT

Larry Sutherland

Good morning

·I was inspired after visiting·

http://info.com/·· search·_ robotic helicopter

L Sutherland_··

Gadgetman

To start off you might want a chopper with contr-rotating blades on a single axle, as these pretty much removes the torque problem(the tendency of a chopper to spin wildly in thee opposite direction of the rotor)

I have a Silverlit X-UFO somewhere among all my crates and boxes(just moved to a new apartment, and my 'office'/'tinker room' only has standing room, and that only barely), which I hope to get to fly autonomously, using a Propeller, a 'Five Degrees of Freedom(XY Gyro/XYZ accel from Sparkfun) and a heap of IR transmitter/receiver pairs for proximitiy detection...
Hopefully I get to start on that project before Xmas...

The X-UFO, if you don't know it, is a 4 x prop design(one in each corner) with a foam body, an iffy Ni-mh battery pack and a rather awful mechanical gyro...
(There's 'a few' sites selling upgrade parts like brushless motors, Li-ion packs, carbon-fibre boy parts, precision propellers, electronic gyros... In fact, they replace everything but the main PCB... )

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Don't visit my new website...

LoopyByteloose

Gadgetman,
I'm really a novice at all r/c flight. Though I have an airplane, everytime I think of flying, the wind is too strong for it. I need to shift over to the newer brushless motors and a completely new airplane that is responsive to the added power. At least I have the r/c transmitter and reciever.

I suspect the contra-rotating blades would handle gusts better than a tail rotor. I believe that is called an auto-gyro - one of the first designs for helicopters. When I tried the small copter [noparse][[/noparse]no gyro] with tail rotor, it seemed that gusts would just catch the tail and randomly redirect all forward motion. A good gyro could also stop that.

I really like the 4 prop flying platform design as it eliminates a lot of mechanical linkage of traditional choppers- everything is done in the microprocessor.

Of course, if you have an indoor arena to use regularly, you can work with small designs and less power. Just having and indoor helium blimp can be quite amusing and I guess you could get by with an XY accelerometer as a stabilizer. Seems like an interesting entry point.

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PLEASE CONSIDER the following:

Do you want a quickly operational black box solution or the knowledge included therein?······

···················· Tropically,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Gadgetman

Actually, an auto-gyro is called that because the rotor is 'auto-rotating', not powered by the engine at all. (An auto-gyro with zero ground-speed will lose control pretty d@mn quick.)
Auto-gyro designs are simply a basic(aeroplane) fuselage with normal tail, stubby wings, a normal airplane propeller in the nose and a rather steeply angled rotor at the top.(It needs to be angled or the forward airspeed won't set it it rotating.)

If the wind is too strong for you, get hold of a 'slope' type RC-glider, like a 'Ridge Runt' or the Ripmax Coyote. small, sturdy and plenty of fun... (particularly if you enjoy builing/repairing them... )
Reminds me that I really need to gt a new RC-rig. The old 27MHz AM set I have isn't safe to use.
(Too many toys, walkie talkies and whatever on that band now) In fact, it hasn't been used since the last time I crashed my Goldberg Gentle Lady and before I built the Coyote...

I have a blimp, too, but unfortunately, the only ones selling helium nearby sells only the LARGE bottles... Anyway, I'd think that with the slow movements of a blimp, a gyro would be better.

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Don't visit my new website...

jsmasterking

I think this should be quite easy, just get a contra-rotation rc heli, take out the receiver and put the stamp in place. The mixer will read the gyro and automatically stabilize heli from spinning, all you have to do is feed out pulses for the servos positions and motor speeds. As for elevation, a simple ping sensor will work perfectly, especially b/c of its conical shape. If you only want it to hover, an ir distance sensor will be cheaper and perform better. You'll also need proximity sensors on the front, back and sides.

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