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Old Feb 13, 2014, 10:49 PM
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12", 3.7g Indoor ornithopter

Airframe:
Wing 12"x4" half ellipse. Carbon rods 0.5 and 0.3mm, 7g/m2 Mylar.
Stabilizer R 4.5 52 deg sector of the circle. 0.3mm Carbon, 2.2 g/m2 Mylar.
Fin and rudder 0.25mm balsa with 0.3mm carbon reinforcements.
Fuselage: 0.8mm carbon tube, EPP foam nose, Balsa+carbon lamination gearbox housing.

Components:
4x12mm Corelless motor
40mAh Full River LiPo
Deltang R42b Rx
Plantraco Nano Act
M0.2 1:125 gearbox

Performance:
Total weight 3.70g
CG = 1"5/8 from LE
Tail installation angle -18deg
Upstroke +30 deg
Downstroke -20 deg
Endurance - up to 10 min.
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Old Feb 13, 2014, 10:51 PM
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3.5g, 12" RC Ornithopter (1 min 38 sec)
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Old Feb 15, 2014, 12:36 AM
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Joined May 2011
691 Posts
Here almost everything looks clear until starting replicating it of course
I like the ruder position, seems efficient and side gusts will turn and bank the ornithopter in the right directions IMO .
What material this "tongue"- hinge that coming out of the actuator coil is made of?
Is it related to the auto centering or is connected to the magnet?

Have you investigated how the wrinkles on the wing membranes and tail affect performance in this scale?

Do you know some algorithm/software for optimization of the reduction ratio ,motor-gearbox efficiency and its weight in the models scale range?

Also gears looks like lubricated? What is the lubricant ?

Very clean, lightweight and simplified design Bravo!

Thanks for sharing Dmytro

PS here is an interesting web site with interesting ideas of one good in the micro stuff guy enjoy if you didn't know him already.

http://micro-plane.com/index.php?opt...mid=14&lang=en
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Old Feb 15, 2014, 01:17 AM
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What material this "tongue"- hinge that coming out of the actuator coil is made of?
Is it related to the auto centering or is connected to the magnet?
The 2mm magnet is held by U-shaped 0.1mm music wire. No centering.


Have you investigated how the wrinkles on the wing membranes and tail affect performance in this scale?
No, but I used to pre-wrinkle film on smaller models, when it is to hard to make membranes smooth.

Do you know some algorithm/software for optimization of the reduction ratio ,motor-gearbox efficiency and its weight in the models scale range?
Yes.


Also gears looks like lubricated? What is the lubricant ?
White silicon grease


Very clean, lightweight and simplified design Bravo!
TY
Thanks for sharing Dmytro

PS here is an interesting web site with interesting ideas of one good in the micro stuff guy enjoy if you didn't know him already.

http://micro-plane.com/index.php?opt...mid=14&lang=en[/QUOTE]

Sure I do, here is another one
http://www.microflierradio.com/

The NANO stuff is not that hard to build. But it is extremely hard to tune and to fly, IMAO. The 5" orni just vanishes in the sky 30' away
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Old Feb 15, 2014, 01:41 AM
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Thanks a lot!
If you don't mind, please post link to the place where such algorithm/software can be found please.
Did you optimized the shown ornithopter by this software ?
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Old Feb 15, 2014, 09:14 PM
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Quote:
Originally Posted by seagull10 View Post
Thanks a lot!
If you don't mind, please post link to the place where such algorithm/software can be found please.
Did you optimized the shown ornithopter by this software ?
There is no link. I did a research on flapping wing in the university. Wrote a lot of Matlab code for data analysis.

As for algorithms, you can find a lot of articles on aerodynamics of a flapping wing.
In some of them you can read about effects of different parameters on the performance of a flapping wing.

I believe you know about this one
http://www.ornithopter.org/software.shtml
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Old Feb 16, 2014, 06:22 PM
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I converted my cheap ebay ornithopter to a spektrum controlled ornithopter.

DSM2 Ornithopter Flying Bird (4 min 56 sec)
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Old Feb 16, 2014, 10:41 PM
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Joined May 2011
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Quote:
Originally Posted by SingSoftKitty View Post
There is no link. I did a research on flapping wing in the university. Wrote a lot of Matlab code for data analysis.

As for algorithms, you can find a lot of articles on aerodynamics of a flapping wing.
In some of them you can read about effects of different parameters on the performance of a flapping wing.

I believe you know about this one
http://www.ornithopter.org/software.shtml
Thanks Dmytro .

https://solarbotics.com/product/gm25/
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Old Feb 16, 2014, 11:25 PM
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Originally Posted by Ron_RC View Post
I converted my cheap ebay ornithopter to a spektrum controlled ornithopter.

http://youtu.be/UancpFE1J3s
What is the overall weight after conversion with the battery and what was the original weight of the original bird ?

Original------------------------------------- Converted

RX,ESC combo---------1.8 g---------- RX HK R415--------------------2 g

Battery 70mA/h 1 cell 1.98 g-------- ESC 3A Brushed with wires 1.6 g

EM actuator--------------0.47 g---------Battery 130 mA/h 1 cell-------3.8 g

------------------------------------------------Servos 2x HK 5320-------------3.8 g
---------------------------------------------------------------------------------------------------------------
------------------------------4.25 g-----------------------------------------------11.2 g


Weight increase 11.2 - 4.25 = 6.95 g

How you manage to fly it ? Overall weight over 20 g ?
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Last edited by seagull10; Feb 16, 2014 at 11:35 PM.
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Old Mar 30, 2014, 06:15 PM
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Joined Nov 2011
164 Posts
Seagull10, I just weighed it and it came to 20g. It seems the brushed ESC I put on it has more power that the combo system's ESC. Anyway, it flies nice but not as long as it did with the original system. I am running a 160mAh battery with a 30C rating and it does quite well. I did have to figure out the CG and now that I have the battery moved farther back it flies even better than in the video. All the best an Happy flying!
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