15 inch span RC ornithopter

[Vincent Lee]

Hi, my son & I have recently developed a small electric RC ornithopter (39 cm wingspan) that flies with authority. Is this a progress in micro ornithopter technology? I have searched infos for small (micro) RC ornithopter, but found only Caltech's Microbat. I tried to attach a photo and a movie clip, but was not able to do so. Maybe later... I would welcome your feedbacks.

Cheers,
Vincent Lee
Seoul, Korea

[eflyer1234]

Vincent,

We would all be happy to see your pictures and video. If you need to, you can email the video to me and I will post it on my website for you.

Congrats on the small size. It has been done before but it is still a feat not many can claim.

-Jeffrey
JGRC
www.jgrc.biz

[Vincent Lee]

OK, here is a picture for model No. 1. GWS B2C motor, home-made micro gear-box (using Micro Servo gears), 7.4V 110mA Li-Po battery, JMP2.3 or GWS micro Rx, JMP 5 ESC, Many parts from Nathan Chronister's rubber powered kit, 28g flying weight, 39 cm wing span. After several trial & errors, now it flies & turns very well. Very stable after lateral balance adjustment (see double sided tape on right wing). Hope it helps.

[Vincent Lee]

Model No. 2. Specs as in model 1 (+Wes-tech LS 2.4 servo), but with a free floating trailing edge, which produces more lift.

[Vincent Lee]

Model No. 3.

[Vincent Lee]

Model No. 1 in flight (captured from a movie clip), piloted by my 10-year old son. Yes, it is easy to control. Some of the mechanisms are patent pending ( ??)

[ornitech]

Vincent,

Very impressive. What is the flight duration? What is the gear ratio and how durable are the gears? I always have problems with stripping gear teeth when I attempt to build models this size.

-Sean

[jms336]

An incredible achievement! How many channels are you using?

Thanks, John

[Vincent Lee]

Sean & John,

I have not tried this yet, but perhaps it will fly as long as battery provides power. I guess more than 10 minutes of flying is possible, and maybe more if we use 150mA Kokam pack instead of 110mA pack (only 1g of weight penalty). The motor, ESC, and battrey are only slightly warm when we land our models in the middle of test flights. This was not the case in our first test models when the gerabox was not efficient. Yes, once durable & efficient gearbox is made, it's almost done. Following Microbat, we started from 22:1, and now 26:1 appears to be much better as it maintains level flight at 50% throttle (about 0.4-0.5 A, 3-4W). We use only two channels. We invented a special mechanism so that both yaw & pitch controls are possible with only one LS-2.4 servo while turning. I think this is a key for the success. I had a problem with usual airplane type rudder or the mechanism adopted in Sean's and Cybird models, although it seems that the former works well in a Microbat model (23 cm span, which will be our next project).

Best wishes,

Vincent

[Jerry Rose]

Vincent: that is a beautiful achievment!! Very nice indeed.

[joe price]

Vincent,
I've been following this Forum for a long time
waiting for something like your design to show up
excellent work.
Any chance that you will publish design or at least provide details of your Special Mechanism?
I've been trying to reproduce the Flapping
Wing Micro flyer that that was shown in Microflight It uses a similar crank for driving flappers.

[joe price]

Anyone on list trying to reproduce Vicent's
design? After several attemps with motors and gear
reductions (currently using m20 hi voltage with
25//1)bird will fly, i have not tried any control
of tail yet i'm not clear what type of control input is required for turns. Also i notice Vicent
used a fin on his tail. Can anyone give me some
insite on what's required?

Joe

[massimo]

Hi to all

Dear Vincent,

when you can sell your sub micro rc Orni . We can hope? You will sell your micro orni?


Thanks in advanced for reply


BEST regards

[Vincent Lee]

Hi Massimo,

It has been for a while since I and my son made our first micro ornithopters. I am a professional scientist working in space science, and the model airplanes & ornithopters are just my hobby. Therefore, I have no plan to sell our orni. If you are interested, I think you can follow what we did. Buy Nathan Chronister's rubber powered kit, get micro motors, Li-Po battery, micro Rx/ESC combo, etc, specified above (or even smaller ones available by now). Make a gearbox out of some broken (or new) micro servos. This part is still the most difficult one, though. Anyone has a suggestion for a good micro gearbox for about 30:1 ratio? I am sorry but I can not describe more on our simple yaw & pitch control mechanism as it is under patent pending, but it seems others working in micro orni's (including Graham in other thread) were successful with the usual airplane type rudder. Hope this helps.

Vincent