wanna get rid of torque affect...update...
 

I am in the works of developing a counter rotating system for small planes, if will loose very little efficiency and may gain it back due to its design, also it will ditch torqu affect and would be way cheaper than those dual outrunner type systems out now, anyone interested in the idea, any thoughts imput...

RE: wanna get rid of torque affect
 

Maxx products (Himax motor) demo their counter-rotate motor in Toledo show this April, using two back-to-back brushless outer runners series together, very neat design. This CR-motor maybe in market anytime, call them to find out. The pix is I found in RC Group.

RE: wanna get rid of torque affect
 

many companies have that design in the works, some are already out using dual outrunners, is that one a single unit?. the others are twin outrunners requiring twin escs, although they are cool, they are not anywhere close to the Idea I am working on, which in some cases will be a better choice than that setup...I just can't say exactly what it is for fear someone will copy it, I can tell you a prototype will be flying by mid august on a gws pico stick f as a testbed aircraft.

RE: wanna get rid of torque affect
 

Please keep us posted on the results. Might have some interesting applications in pattern.

RE: wanna get rid of torque affect
 

yeah, it could definatly have its place and should be fairly efficient still, I will keep you updated here, and will try to have the hard part done before august, thats just when I will be flying home an can ship my motors and gear back to here where I am living for school, that way I can get this thing in the air...

RE: wanna get rid of torque affect
 

OK, more details about the Maxx Product's CR-motor, since I'm testing their Himax 6332-230 motor (equivalent to AXI 5330/F3A), so I know their new motor design progress.

The Himax CR-6320 is using two Himax 6320 brushless outer runners. This prototype is currently tested by Dan Landis (see pix) after Toledo Show. As I heard:
1. Load for two motors are significantly different: the second motor drives more power than the first one, so you have to use two esc.
2. Still trying to find out the best propeller combination: two propellers can not use the same pitch. For Pico-stick size motor you may not see the difference, but for the big 2000W motor for 140-size patternship, the noise is terrible and currents on two motors are significantly different!
3. When first motor is driving ~28A and the second is driving ~34A, the testing airplane can do ALL 3D stuffs.

The original Himax 6320 rated ~2000W at ~70A, so it is only testing around 50% power. I talk to Jarvis Yeh, designer and owner of the Maxx Product, the pre-production CR-motor will be available in 4 weeks.

Jason, you may call them to ask a sample for testing in pattern flight!

The only draw back of CR-motor is its weight. More pix can be found in here http://www.maxxprod.com/mpi/newdevelopment.html

RE: wanna get rid of torque affect
 

yeah, that system is fine for the big stuff, as you mention the wieght is a problem, the need for two escs, the need for heavier batteries I'd assume, my system is not a dual motor system, I was just kicking an idea around one day and something great hit me, I have it scetched, I will be building it soon,(sucks being in school and having no money) so it will be cheaper, still get rid of torgue, be more efficient than those dual motor setups, should work out well, I will start with two of the same pitch props as it will be a smaller model, and shouldnt present much problem... you'll see it as soon as its built and I have somethi ng to protect the rights to it, I am hoping a company will pick it up if theres interest in it, making it available to more people, and putting a few bucks in my pocet also, I think itd be cooler to see people using something I designed though, but I wont complain about free money...looking to get rich, no, but a couple bucks wouldnt hurt...

RE: wanna get rid of torque affect
 

At a contest in Liechtenstein, earlier this month, Michael Ramel flew a model with a counter rotating prop. I don´t know any details about the power system, but i´m curious about this idea, too.

RE: wanna get rid of torque affect
 

Yeah, well I am building one regardless that will be easy to size up or down to fit any application, a bigger one would actually be easier to build, but as long as interest is generated then hopefully a manufacturer will by the idea from me or pay me a certain amount of the profits to use the idea...that way it would be mass produced an will cut the cost of counter rotating in at least half of what those dual outrunner setups cost, maybe cut it by even more...Plus it could me made to fit any multitude of motors without to much work...I am glad people are interested though...

RE: wanna get rid of torque affect
 

The reason of two ESC is not only for big battery packs; when balance the torque (using the same pitch prop in opposite directions at same rpm), measured current load on two motors showed big difference. As I mentioned, in one case, motor one is ~28A and motor two is ~34A. Two propellers have different initial (air flow) velocity. The first one is the speed of airplane, and the second is washed out after the first propeller. To optimize the counter rotate propellers, you can use

1. Same rpm, same pitch (in opposite directions), but different currents (need two esc)
2. Same rpm, different pitch, same current (use one esc, or gear-linked from one motor)

I believe these are what they are working on now. In your case, I think you're case #2.

If just use gears to drive CR propellers without consider about these, then your setup may look fency but is not optimized for pattern flight. Again, you may not see the difference in small pico-stick size motor.

There were many full-scale CR propellers reseaches back to 50', just wondering if any data are available to modelers.

RE: wanna get rid of torque affect
 

NOPE, Mine would be a third type, not fancy, not inefficient, like I said I cannot tell right now, I always think outside the box, it should work very well, and my pico stick will just be beacuase the slope kit is like 15 bucks, meaning its a cheap and stable flying testbed, after that it will be put on a small 3-D model, I would go pattern but dont have the space to fly a pattern plane in front of my apartment...this things gonna be cool, flight times will be the true teller of the effiency compared with just running a standard setup...should be interesting, I can't wait to start it up the first time and see it lift off...

RE: wanna get rid of torque affect
 

I'd imagine the rear prop needs more? pitch, as the initial airspeed is greater.

RE: wanna get rid of torque affect
 

Found two more pix, just wondering how it works? Single motor-gear drive, or two motors? Should be very interesing in pattern flight w/o torque!

RE: wanna get rid of torque affect
 

Hes either got a gear drive or dual motors in that...my system is definatly different, that is a cool plane though, I also wanna try a hover with no torgue in a 3-D plane so we will see how it works when I get the stuff and get it built...

RE: wanna get rid of torque affect
 

Hi Guys,

Michael enginered an original light and effective system: only one motor/esc with one gear box which is also a "differentiel" driving both props. (differentiel: is it english? [&:] It's like the device between the wheels of your car!)
So, you get exactly the same torque on both props.
The contrarotatings props should be very nice to reduce/remove single prop's side effects: torque, rotating airflow, P-factor, gyroscopic precesion, but keeping gyroscopic stability :D.
Michael is still experimenting but it works great. Engine is perfecly in the plane's longitudinal axe, rudder action is symetrical.
The noise is different but nice to hear. He reduces it a lot by reducing the rpms, big pitch and big prop separation.
I would like to test fly his plane :)

RE: wanna get rid of torque affect
 

Yeah, well gearboxes are fine, beats having to buy twice the stuff, the twin motor design is cool too, I have something though that hasent been seen before, which is why I even bothered posting, because when VPP came out look how thats taking off, so hopefully when I release this idea it will take off, I was a CNC machinist for a year and have been building and inventing things for almost all of my 19 years, I am suprised I didnt think of this sooner as I have been flying 3-D for about a year now, and interested in it for about 3 years, so this should be cool, especially for stuff like pattern and a few other things...

RE: wanna get rid of torque affect
 

Thanks Benoit, that's really a good detail information. The single motor setup is much lighter than the two motors setup for sure.

Luke

RE: wanna get rid of torque affect
 

mine should eaqual it and if I could see the gearbox Id prolly say it will be lighter, so we will see...

RE: wanna get rid of torque affect
 

well I have a list of all my required items made up on tower, got a plane in mind other than the pico stick F, I need a new foamy 3-Der anyway so it will be built onto t pitts bi-plane from hobby lobby, the new white one they have out, should work out real well, mid august will definatly happen now, this thing is gonna be awesome to fly...anyone know or work for any companies that would show interest in this, so far I have e-mailed electrifly but I don't know if the email got through plus it didnt tell any real details as to protect the idea...in august you'll be seeing some photos of it here, but I will be hiding to CR mechanisin somehow, but you'll be able to see the motor and props, just not in front of or behind them, I may even block out the motor, but you'll get an in flight shot too hopefully to prove its working...for those non-believers if any out there...

RE: wanna get rid of torque affect...update...
 

well I have heard back from hobbico aka greatplanes, electrifly, and they seem interested I e-mailed them back and believe it has a chance of being picked up, I sure hope it does...flying in 2 weeks or so

RE: wanna get rid of torque affect...update...
 

How come this forum ended?