[MOC] Tandem Helicopter

[colinrichardson]

I started this project a few years ago but let it sit dormant. I've started it up again and figured it would be good to track its progress and start getting some feedback (though there's not much to critique yet).

This is going to be a tandem helicpoter loosely based on the Chinook. I'm especially interested in mimicking the Chinook's flight controls and expect this to be the biggest challenge. The real helicopter's controls uses a sophisticated, for its time, hydraulic system to mix inputs from the throttle, stick, and pedals into outputs to the rotors so that it "feels" to the pilot that they're flying a more traditional helicopter.

Though I briefly considered using pneumatics to create the control system, the lack of pressure variability made it an unappealing option. Instead, I'm working-out a mechanical gear and axle system to combine and actuate the controls. I may convert to an rc/servo system in the future, but plan on only motorizing the rotor's spin for now.

The crude testbed / proof-of-concept mockup that I'm starting with.

I'll upload some more images over the next few days.

[steph77]

Hi,

If you are interresed i realise a full set of chinook mixing comand. This is the most challenging part of the Moc for sure.

Here is the vid:

and here is apic of what i arrived finally by compressing at max the command system at this page (the system doesn't allow me to post directely here?)

http://www.techlug.fr/Forum/topic6224-15.html?hilit=chinook

[adunaphel1]

Interesting project.

I'm a conformist!!

[colinrichardson]

Hi,

If you are interresed i realise a full set of chinook mixing comand. This is the most challenging part of the Moc for sure.

Here is the vid:

and here is apic of what i arrived finally by compressing at max the command system at this page (the system doesn't allow me to post directely here?)

http://www.techlug.f...l?hilit=chinook

Very nice work - I hadn't seen it before. I've been focused on gear mechanisms for the control combinations but your lever-based system seems to be very elegant. It's going to take me a few more work sessions to install and test my current design, if it fails (too much friction etc) I'm going to give your system a try.

Thanks.

[colinrichardson]

A few videos of the mechanisms I've been working on:

The control combinations discussed above- one is linear-actuator based: https://flic.kr/p/r86eSo

the more compact one uses worm gears and racks: https://flic.kr/p/qSVTri

The rotors and swash-plates have been through a number of iterations and are remarkably similar to designs by some other MOCers I've seen recently.

Cyclic: https://flic.kr/p/r86phf

Collective: https://flic.kr/p/qSW18K

In Motion: https://flic.kr/p/qdA9LP

Finally, a quick look at my first attempt at a control stick mechanism that outputs rotation: https://flic.kr/p/qSNt7j