RC India

Hi everyone! this thread is about me and my team's attempt at building an ornithopter as our final year project.We were inspired to do this project by watching the amazing builds flown by
Kazuhiko Katuka http://homepage2.nifty.com/smark/HabatakE.htm (http://homepage2.nifty.com/smark/HabatakE.htm) and Joydeep Bhowmick http://www.rcindia.org/kites-trains-free-flight-and-all-others/rc-ornithopter (http://www.rcindia.org/kites-trains-free-flight-and-all-others/rc-ornithopter)

We named the ornithopter 'The Misago' which means Osprey in Japanese. Now you may ask why a desi ornithopter has a Japanese name ?-well we thought it would be 'cool'. little did we know at that time that thinking up a name and building an ornithopter are completely different ;D.

So let me first start by admitting- we did not manage to make our Misago fly, but we did manage to learn a lot on the way! I would like to share our experiences and the problems we faced and how to avoid them with people who are interested in building an ornithopter. That is going to be the entire objective of this thread. So if you are interested, please read on...

When we started, we built a rubber powered model made of ice cream sticks, wrapping paper, rubber bands taken from the sky captain rubber powered model and wires.The design was loosely based on 'the freebird' http://www.ornithopter.org/plans.shtml. (http://www.ornithopter.org/plans.shtml.)

The rubber powered model flew after a few attempts- https://www.youtube.com/watch?v=Svq3u-diAT4 (https://www.youtube.com/watch?v=Svq3u-diAT4)

Now,the initial design was done in Google sketchup8.
The design influence primarily comes from the Sean Kinkade 'Kestrel', kazuhiko katuka's ornithopters and Deepu 5292's ornithopter http://www.rcindia.org/self-designed-diy-and-college-projects/my-ornithopter (http://www.rcindia.org/self-designed-diy-and-college-projects/my-ornithopter) (the acrylic body idea came from him) and arun.sreelakam http://www.rcindia.org/kites-trains-free-flight-and-all-others/rc-ornithopter-homemade (http://www.rcindia.org/kites-trains-free-flight-and-all-others/rc-ornithopter-homemade)

Hi there! I have seen the videos of your ornithopter on youtube and I am very impressed by them. They are as good as those by Mr. Kazuhiko!  I have a few questions  If you could help- 1) Is that a ball joint? 2) How did you make this crank joint ?3) How is the CF rod fixed with the aluminium shaft?4) How are the articulating rods fixed to the body, and how do you figure the correct distance?5)Where do you find lightweight gears,were they made?6) what is the motor which you are using? and7) finally what material is the wing made of? It would really be great if you could give some solutions.Thanks in advance!    what about this then u did not get anything out of it      https://www.youtube.com/watch?v=aTbNwfZ4Alw (https://www.youtube.com/watch?v=aTbNwfZ4Alw)

Quote from: ash on March 10, 2015, 10:23:00 AM
   what about this then u did not get anything out of it      https://www.youtube.com/watch?v=aTbNwfZ4Alw (https://www.youtube.com/watch?v=aTbNwfZ4Alw)

Hey Ash!
your demo video doesn't quite explain how you made your gears now, does it?. It would be great if you could elaborate on that! good advice is kinda hard to come by...

Now, the problems started arising once we had to figure-

1) What motor to use?
2) The gear assembly setup and no. of stages, no. of teeth on on each gears.
3) How to match the flapping frequency (in Hz) with the RPM.
4) How to convert the rotation of the crankshaft into flapping motion.

The first thing I did was call up VC sir. It was a characteristically 'VC style'  short conversation.

Me-" Hello VC sir, I was building an ornithopter. Do you have any idea how to build one and where I might get the gears for it?"
VC-" No idea "
Me-" Well do you know how I could fabricate the gears?"
VC-" None at all"

There! I was on my own.

So, I designed the gear box based on the BC 5010/14 360 KV motor sourced from rchobbyaddict.com with the following specs-
1) 3 stage speed reduction
2) 6 gears- pinion teeth with 26 teeth,then 60,25,60,25 then final driven gear with 60 teeth giving a reduction ratio of 13.29 (see figure)
3) Gearbox plate made out of 1.5mm thick carbon plate.
4) Gear shafts made of 4mm thick solid CF rods. ( a CRITICAL MISTAKE, I will tell you why soon)
5) Gear box plates held at appropriate spacing with 3mm brass screws.( later replaced by nylon ones )

The calculation was simple 360 kv motor runs with an 11.1V battery = 3996 rpm. At 80% it gives 3196.8 rpm which after going through reduction (3196.8/13.29) gives 240 rpm which is equivalent to 4Hz flapping frequency.(f=N/60).

uploading a video now i used 2560kv motor with 7.4 volt battery  i used nylon gears 48p  maingear is 66T spur 60T   http://youtu.be/U6sNZGiYXRU (http://youtu.be/U6sNZGiYXRU)

video is private! ???

now its working video link

post some close up pics, would be nice

2015-03-18 15:39

INDIA, MUMBAI EMS, Record item customs information (Inb), Air, CUSTOM EXAM MUMBAI, Retention reason : Call Customs 022 26156063 OR Email

please help me, what i have to do
i buy 3g smart phone from aliexpress $58
i have to wait for get my item
what i have to write in email or what time i have to contact mumbay custom

http://www.birdkit.com/models.gbx.html (http://www.birdkit.com/models.gbx.html)

Hey Irfan , I have no idea why you are asking about customs, (that too about 3G mobile phones) in a thread about ornithopters.   ??? PM senior members for queries about customs.. 
 

So coming back on the topic of gears ( I post once in a couple of days ), anyone who has tried making custom gears will understand that finding specific gears is tough in India.
You have limited options- either you have to use printer gears(like Joydeep did) or gears out of toys both which may not suit your needs.

Fortunately, there are lot of online resources in how to actually produce laser cut gears. I used this as my guide-  http://makezine.com/projects/make-your-own-gears/ (http://makezine.com/projects/make-your-own-gears/)
another awesome site is https://www.ponoko.com/login.You (https://www.ponoko.com/login.You) will need to install inkscape where you make the 2D design.

Using these as step 1 and 2 and selecting acrylic as option (5mm thick) , I ordered the laser cut gears from Ponoko UK- thats the cheapest of all the other options. US,Germany and Australia charge exorbitant shipping charges...

I could have used laser cut gears made in India but I did not know any manufacturers. If you do know any who can custom laser cut parts in India please let me know :help:
Shipping was fast, came within 30 days( that too to Guwahati !)

Now that I rethink there are better ways of making gears, if you know any CAD software such as google sketchup, FreeCAD you can have your designs converted to .stl file format and have them 3D printed right here in India at-
www.nutsandboltz.in (//http://) (//http://) (//http://)
http://www.3dprintronics.com/3d-printing-services (http://www.3dprintronics.com/3d-printing-services)

additionally search- http://www.hobbyking.com/hobbyking/store/__423__59__Electric_Motors-Gearboxes_Parts.html (http://www.hobbyking.com/hobbyking/store/__423__59__Electric_Motors-Gearboxes_Parts.html) if you want readymade gearboxes.

....super stuff  :thumbsup:

this build log was posted in  March  2015 , i wish @Fw190 will  complete it , will be better if you post a video too :0