Simple active-twist mechanism for an ornithopter

[@AndyFromBeaverton]

Kazuhiko Kakuta in Japan has mastered these movements a long time ago. I hope you have seen his massive collection of unique ornithopters.

[@XXXmags]

Dr. Kazu is a legend when it comes to these machines. Great work on his part.

[@harveylorenzedejesus2383]

Clever!! Genius work you're doing right there.

[@user-ew7nz3yw2i]

Nice geometry! I was not expecting....the great looking glide lock. Wow.

[@XXXmags]

Thanks! see this video for more details on the glide lock: kzbin.info/www/bejne/rGHdYqKgpdSYnrM

[@promitchakraborty]

Beautiful

[@onuralkaya8744]

You have made a very different and very good wing mechanical design. I think it will be very efficient. It is very good in wing design, and very compatible with mechanical design. The wing performance in slow motion seems very good and efficient. Congratulations and good work

[@XXXmags]

Thanks! It's very simple for what it does.

[@TheWindGinProject]

Have you ever considered a fabric type wing that uses a simple check valve system? Example; when the wing is on the up stroke, air is allowed to flow through the wing.

[@XXXmags]

Yes. I've had mixed results with this concept and its not as efficient as one would think. Please see these posts: Clutch wing: www.rcgroups.com/forums/showpost.php?p=43071065&postcount=159 Rotating LE spar: www.rcgroups.com/forums/showpost.php?p=49687763&postcount=209 Asymmetric elasticity: www.rcgroups.com/forums/showpost.php?p=49685699&postcount=208

[@TheWindGinProject]

@@XXXmags Not the check valve design I'm thinking of but thanks.

[@eddieharris3150]

Interesting design but why go to all that trouble, and added weight? Doesn't it do that passively anyway, especially if you leave the front spar not connected to the wing fabric, basically in a tube. The fabric will rotate on it naturally, creating the same effect, and if you're trying to limit the twist, that can easily be done

[@XXXmags]

Passive twist will cause the wing to deform under load. While it works to generate thrust, it will also cause the wings to deform when countering weight. So you strike a compromise between a good-enough twist distribution for lift, and a good-enough twist for thrust. Passive twist also generates thrust inefficiently at higher frequency, since the wing cannot twist fast enough. See: Analysis of wing twist: www.rcgroups.com/forums/showpost.php?p=49734105&postcount=226 Active flapping mechanism: www.rcgroups.com/forums/showpost.php?p=49734129&postcount=227 Lastly, this mechanism shown here is just a couple of levers and some links. It's quite a small weight penalty. It also adds the equivalent of aileron control.

[@sennlich]

and where is the fly footage?

[@XXXmags]

See this video: kzbin.info/www/bejne/eXavZKKrd9-Eh6s

[@k1ortia]

D.A.R.P.A hold our Beers...

[@maxra4277]

in the real ornithopter the drive was a piezo crystal drive ))

[@Drenov]

Was there supposed to be anything clever in this?

[@XXXmags]

There's a lever that twists the wing.

[@icarusix8750]

I didn't see much better on your channel. You're subbed to some great channels, I would've thought a watcher of them would be above a comment like this