icecool2

Hey Everyone,

I'm on a team at Drexel University in Philadelphia that's designing an autonomous control system for an RC micro-helicopter. We had a Kyosho EP Caliber M24 in the lab, but that can barely lift its own weight let alone the electronics it will need to carry. We're looking for a heli that can lift at MOST 2 pounds, it will most likely be less than 1 pound. We're not really familiar with this area so I was hoping you all might have some suggestions for where to look or specific ones. Maneuverability is not important since this first model will really only be a proof of concept type use.

Thanks for the advice!

dinuka

T-REX might its the best heli in the market that i'm aware of pretty solid neatly assembled my friend has one I have a dragonfly 36 still working on it if it worked i'll let you know but the t-rex I think it will lift a pound if you had a powerfull motor like a 4200kv and will cost about $500 to complete

credence

My Feedback: (2)

T-rex won't lift 2 lbs. Not even close.

For that kind of weight lifting, you're going to need a bigger electric. Something in the .30 size range. Mikado Logo 10/14 or Ikarus eco-8/16 would work. Maybe even a corona 110 with a good brushless setup.

All three would be able to lift this weight with the proper power setup, but they will all cost you quite a good chunk of money to get flying, and they're all kit form and so require assembly, and a general knowledge of helicopter mechanics would be needed to set them up and fine tune them.

There may be other "in between" kits that might do what you want, perhaps someone else can help.

icecool2

hmmm..... well, can you maybe provide which micros can lift more than their own weight? We can make it fit within the constraints as long as they are not too small. I'd prefer something that doesn't require too much extra knowledge to build. If it is just putting it together, that's fine. We can handle that, but if it requires any special reworking, that's probably outside of our realm.

I think we can make our system weigh less than a pound. I just would like the freedom to add some additional parts if we need to.

VinceHerman

Most helis require this tweaking to make work. And if any of your test flights are less than perfect, you will trash the heli and have to use a fair bit of knowledge to replace the broken and bent parts, and tweak things again.
Do you have a budget in mind?

icecool2

Well, tweaking is fine. Just major changes that require years of experience aren't. If we need to machine a part, that's fine too. I'm not too sure what you guys consider tweaking. I'm not so worried about test flights and crashing, we have a rig to allow controlled indoor flight without the risk of crashing. Our budget is pretty large, but given the chance that we may need to purchase more than one heli if we crash them off of the test rig, I'd like something under $300. But, I'm open to anything. Do you have something in mind?

colrod12

I Have A Trex XL CDE
AON 3500kv Motor
Castle Creations 35 amp ESC
Perculating With
Thunder Power 2100mah 11.1 battery... for S h i t s and grins I Just carried a bag Of peanuts (sealed) that Weighs 1lbs
From One Side of my living Room to the other With my trexer.
Don't know How many times I could have gone back and Forth because i Crashed[:'(] making the Peanut Drop Over There.
But At least I Know My Copter can Pick Up a Pound Of Peanuts Anyway
A
Trexer Like This Is About At The Very Least $600[&o]
Sounds To me From You'r Comments Of Who You's Are, You's Would'nt have Any Problems Building,trimming And Flying a Heli

oops

Hi Icecool2.

If you want something in that range, you may have to get creative. Also, you haven't mentioned how long it has to fly for. That's going to be the final killer for your application.

You might like to look at the AluSEF (Aluminium Super Easy Fly) which is reasonably strong, but quite light. Then you will need to upgrade the tail gears to steel or replace the shaft with a belt. You can extend the tail about an inch, and then install T-REX main blades, and a T-REX 420 LF motor! Since weight is important, gears are probably a better idea for the tail, but the brass ones are crap.

The AluSEF is a lot smaller/lighter than a T-Rex, but since it's quite strong, and you can upgrade to a big T-Rex motor and blades, should give you a weight advantage.

Now every gram is critical. Since you will be proving controls, scrap the Gyro and maybe the receiver. Use 7g or 8g servo's. Also lose the extra fiberglass on the tail, and remove as much as possible from the body. Maybe even use a thinner diameter boom.

Then use an 800 maH 30C LiPo.

It won't fly for more than a few minutes, but I think you will find it will get you close to a pound lift capability.

And finally, make whatever you stick in it as light as possible.

Alternately, build your own heli from scrap....

Walkera 4/ Dragonfly4 etc Fixed Pitch modules are cheap. You could buy three and join them at the tails to make a tri-rotor. That would, when lightened and used with a LiPo, easily lift more than a pound, and cost next to nothing to build. And you could even get rid of the servo's... Maybe lift 2 pounds.

Just be creative.

Or as Credence points out, consider something serious in terms of size

David

bdavison

My Feedback: (1)

I think the Trex would work, and it should lift at least 1lb - 2lbs might be pushing it. It's going to degrade performance though, no 3D stuff, but it should work for normal flying. No telling how much it would actually pull, without testing it.

There are also systems available that may be able to reduce weight and still offer you some of the features you'll need for this.
The Co-Pilot is a box that attempts to keep the helicopter level based on it "seeing" the horizon in a 360 degree field of view. Combined with a good heading hold gyro like a GY401, much of the tasks your autonomous computer would have to deal with could be assigned to existing available equipment. Possibly further reducing weight of your system.

Carnegie Mellon has an outstanding Autonomous Helicopter Project They were doing full unaided flights in 1998. They were running a MUCH larger helicopter for their tests. A Yamaha R-50 if I remember correctly.
You can contact them at:
Carnegie Mellon University
Robotics Institute
5000 Forbes Avenue
Pittsburgh, PA 15213

There are a few people I would suggest you contact for more information
Marco La Civita - He's the mechanical engineer for their project.
You can reach him at [email protected]
and
Ryan Miller - He's one of the robotics engineers
You can reach him at [email protected]

Im not sure if these e-mail addresses still work, but its worth a try.

I'd also suggest contacting the Association for Unmanned Vehicle Systems International
They have a contest every year for these things, and award $60G's to the winner.
Their website is http://avdil.gtri.gatech.edu/AUVS/IARCLaunchPoint.html

thecheatscalc

well, I think you could try making a large draganflier out of 4 / 3 walkera 36's really mine alone can lift the body at a total weight of 720g, on one of those cheap li-polys, that aren't flight worthy, as well as a 25A esc and the align420LF. if you got more powerful engines you could probably lift quite a bit more than that. good luck on this thing. what's the total budget and what're you trying to lift?

icecool2

Total budget is several thousand dollars. The budget for the heli is around $300 each. I've been speaking with someone at Kyosho and they tell me that the caliber 400 will lift half a pound with a LiPo battery and brushless motor.

thecheatscalc

well if you tried making a four proped 36 with a 8800mAh lipoly on it as well as some nice brushless motors, that would lift quite a lot. oh you forgot to mention, what're you trying to lift and what is that object(s) for?

bdavison

My Feedback: (1)

He's gonna be lifting the autonomous system..

Normally it includes a GPS for guidance, Laser or radar avoidance system, Gyros, computer for holding the programming, etc.

Lots of stuff to cram into a lb of cargo.

icecool2

bdvasion is on the right track. The system will consist of GPS, a DSP chip, accelerometers, magnetometers, etc. All in all, the board should weigh somewhere around 1/8 to 1/4 of a pound. My concern for additional weight is if we decide to add additional batteries or if any new sensors are added that we didn't foresee.

I really appreciate all of the advice you guys have given me. Kyosho has assured me that the Caliber 400 (should be out next week) with a LiPo battery and a brushless motor will be able to lift at least 1/2 a pound. How do I go about choosing a motor and battery?

oops

Hi Icecool2.

If you're working from a recommended model, go with the motor, ESC and battery they recommend also -

Especially if you've managed to get a suitable spec from a supplier

Otherwise, you'll need to get some technical information from the supplier and work it out. (eg, what main rotor RPM, Gearing, Estimated current draw etc).

David

thecheatscalc

heh or you could talk with the airplane guys and make a draganflyer with turbines instead of props, that would be cool.

Ok for a brushless motor you'll probably want something in the 4000KV range, as well as a 40A min ESC. With the li-poly you'll need a discharge rate of probably 15C. or you could get some of those 30C li-poly batts and take those and re-wire them together for a 2200mAh battery.

good luck on this thing and I want to see what it looks like once you're done! you could cut off grams by replacing the stuff with carbon fiber parts. this looks like fun

THECHEAT

mazakari

LOL This made me laugh. I would love to have been there !!!

About a week ago I did some underslung work with my TRex (don't ask why). The load was just under 1 pound in weight. I am running a 400LF with a Align 25A esc. The heli lifted it no problem, and my TRex is a bit of a fat bird too, coming in (ready to fly) at 1lb 10oz (750g). Thats an all up weight with load of nearly 2lbs 10oz !!!!! If you can loose some weight off the heli and fit a decent motor and esc it should pull a decent weight. Flight times will be low though.

Taking the strain



Waiting for the load to steady



And we are away !!



Jon

credence

My Feedback: (2)

Such abuse of a nice helicopter..!

darthdrk

The Corona can lift quite a bit of weight well over a pound in stock form.There is a stretch kit available from BallisticTechnology.com which im sure will put you in and over the two pound
range. Some are even using the Corona as an aerial photography platform. Its pretty versatile and its not complicated to set up.