Hello all.
I have a question please.
Is there a way to use coax mounted motor like with coaxcopter for arducopter, but with arduplane, for a tailsitter configuration ?
My physical frame is a coaxcopter with wings.
I’d like to use différence of thrust for roll control in plane mode after transition.
Thanks for your reply.
I recall helping a person with single-copter-like plane controls. I am not a Plane expert by any means, but I could not find a way to split a rudder in two different surfaces (otherwise copter-yaw control was incredibly poor), so I had to implement additional surfaces in the firmware, which I called “rudderons”. This worked for that person after few priority adjustments (like, which axis should let go first under which conditions), but eventually this went to nowhere, and I felt like there is no chance this was acceptable upstream.
However, my impression is that differential RPM, employed by coax copters, would be a very poor plane roll control. Slightly non-symmetric wings, and you are saturated in roll once you have enough speed, which sounds like an imminent crash.
As a somewhat coax copter person (e.g. see the profile thumbnail), I may help you with custom frame code and stuff like that, but you want some aerodynamic roll control by wing surfaces too.
Thanks a lot for taking the time to reply!
I think it’s possible to manage the roll using the torque difference, exactly like ArduCopter’s coaxcopter model. Yes, I would be interested in help implementing the model in ArduPlane, in case there’s no way to emulate it using special functions.
With what control surfaces?
HI ! Only with pitch and yaw surface (exactly like coaxcoter frame class in arducopter), but i want to benefice from transition to level flight with arduplane
Have you looked at this:
This (both the article and the available options in the code) don’t cover a single-axis design with two counter-rotating propellers (I believe at least), and I believe this is what @Julien_Theodore wants to have.
Again, my belief was that OP’s machine uses surfaces to manage pitch and yaw, and differential RPM to manage roll. (And these surfaces will be in the wake of the motors).
In the design you are referring to, to the best of my knowledge, the logic for generating RT and LT totally ignores the momentum and solely manages yaw by differential thrust, whereas roll and pitch are managed by tilting these motors or by additional surfaces.
@Julien_Theodore I’m a bit busy right now, but I’m planning to recall how things are done properly in Plane by looking at my own “rudderon”-related patch, and to produce something to manage the coax layout. I will probably start a private thread for communicating how to work with this, because from my past experience things will get very wordy very quickly.
I’m still not sold on whether differential RPM for roll on a Plane is a good idea, but why the hell not trying. (Right now I’m assembling a new coax, that can also work as a singlecopter too, to finally start bringing together all my experience and to deliver the new code for SIngle and Coax because the existing one honestly sucks - so I’m going to be elbows deep in frame code anyway)
Yes but no configuration correspond to coaxcopter.
Only 1 moteur (like 3D plane) or 2 motors like taimsitter but not coax.
