Wednesday, 29 April 2020

So what to do next ?

So after completed few rubber band powered ornithopters I realised it is nice for startup and learning but it is essentially dead end. There is no indoor flying venues in my town and it requires zero wind for flights which is only few times per year. After watching nice inspirational videos on You Tube about ornithopters I decided to go for RC controlled one.
I have never done it before so I started from scratch. Yes it is 50 times more complicated than rubber band powered ones. I bought X wing E bird toy from the internet for $ 32 to se how does it works. It arrived together with small RC transmitter 2 channels, ESC control and actuator controlled ruder like airplane. I flew it in nearby park and it flyies , Bit difficult to control and if motor cuts off mid flight it nose dives to the ground. But did not break. I decided to use E bird internal organs and tail and try to implant it to my monoplane ornithopter rubber band powered. 



Soon I realised it is impossible. Changed plan to build my firs RC powered ornithopter around mechanism from dead E bird. It proved to be far more complicated than I expected.
When finished motor could not make even one flap and cut off, with my wings 40 cm wide.
Torque was to high to move bigger wings than toy bird. Gear ratio was 1:26 pretty high flapping rate. I could not change that, so i put smaller wing same size like original bird but only monoplane. So wings area is half size of x wing double wings E bird. Bird weight is 18.5 g. Same as original one but half wing area, very high wing loading. I was suspicious that it won't fly at all. 
First version all balsa wood frame  CF rods wing spars modified gear with single crank shaft. Transplanted original tail, no time to develop mine.



So first flight in local park.
Watch that on this link

Yes it can fly somehow. Wing was to small for 18.5 g weight. But motor and transmission 1:26 can not drive bigger wing and that was it.
After many heavy crashes every pice of wood was broken. Only wings, mechanism and receiver did not. I tried to improve steering by side truster 4 mm nano motor and prop.
With 6 mm motor and 70 mAh LiPo battery it could fly around 6 min.




Monday, 27 April 2020

Apart from my artistic painting I also like technical stuff. Its a bit like curse if you have multiple interests to enjoy. I took little break from painting now. While sitting in my backyard watching birds flying around I was curious how do they produce lift and thrust by flapping wings. I started watching different articles and videos on the internet about that. Accidentally    I came across  some thing I have never heard of called an ornithopters. I was hocked up.
It looked like very nice to do some fine technical things when have free time (semi retired now). And few months ago I have built my first rubber band powered ornithopter by free plans from website The ornithopter zone. Was not so simple to by different materials and parts, learn about glues. etc. But I have done few of them. They flew nicely but with rubber band power and without any controls flight where very short and unpredictable.




This video is recorded with iPhone camera  slow motion 240 Frames per second.
Actual flight lasted only about 30 sec.
Watch this on You Tube
While ago when I was living in Croatia I enjoyed flying ultralight aircraft called trike. It was very nice only with helmet and in t-shirts flying over nice landscape like a bird.
Aaa happy days. There is some photos from my former air club back there.






I did not fly since I have migrated to Australia 21 years ago. To expensive and to windy for flying trikes here in Perth.