Hi, I’m working on some custom builds and would like to implement tilt rotor capabilities to a quad or X8. See below link to an example. I’m seeing many racing drones now have the ability to tilt all 4 rotors in order to gain faster speeds and less body drag (since the rotors are tilting and not the whole body to gain speed):
Does ArduCopter support this type of frame and mechanism? I know ArduPlane has support for Tilt rotor for VTOL purposes. Taking it further, can it support an X8 configuration (OctaQuad copter)?
ArduCopter doesn’t. But what you can easily do (and what I am pretty sure they are doing in the examples you link to, and other similar) is mix in tilt servos input in your radio. Might be a bit of trial and error at first, but should work well.
I suppose you could, as an alternative, try loading plane and using modes QSTABILIZE, QHOVER, QLOITER, QLAND or QRTL. And never initiate a transition! Don’t see why this wouldn’t work in theory, although somewhat of a not so good hack, and haven’t ever tried that so don’t know for sure. Also wouln’t be suprised if there’s something specific to plane that would prevent you to do so. Tridge could confirm or not.
G’day Alex!
To offer a different opinion: Copter doesn’t do output mixing/blending, so as you tilt the motors forward you’re likely to get unusual control responses (normally increasing the two left motors would cause roll. Tilt them 90 degrees, and the same output from the autopilot actually causes yaw). Quadplane understands this logic. Not sure anyone has done an octo tilt rotor @tridge ?
Good point. I was thinking in terms of mixing tilt with pitch only, and only in a symmetrical and completely proportional way on all four motors. (As would be ensured if you were titting arms instead of motors, and both with the same amount).
@OlivierB/@james_pattison
Thanks for your input. @OlivierB you are correct…I’m thinking pitch as to rotate the arms (all 4 at the same time) to provide faster forward proportion. Essentially the same as shown in the linked videos above.
Has there been any discussion with ArduCopter providing this functionality? Is it something on the drawing board for a future release? Just out of curiosity, how are other tilt-rotor racing drones accomplishing this? What firmware are they using?
Not that I know of in terms of integrating into copter, but would be nice.
I think AliShanMao only modified radio and used stock firmware, probably cleanflight or naze32 given the date, but not completely sure, nor do I know if there’s been some code mods to those to make this work better. Also since these are racing drones they don’t have to worry about loiter or poshold.Or even stabilize.
It has come up, as has the pusher prop (5th motor) configuration. I don’t think anything is planned though.
I’ve seen it done with kk2 and betaflight, I’m guessing they use a custom mixer to blend roll and yaw based on the servo position but haven’t checked.
unless there is a particular “copter only” feature you need, I’d try using quadplane, with some “generous” QAssist settings - QAssist being how the code uses the vtol motors to prevent stall. It’ll take a little playing around, but will work.
Actually, hold on that. I’d have to look at how QAssist treats tilt rotors.
Don’t see why this wouldn’t work in theory, although somewhat of a not so good hack, and haven’t ever tried that so don’t know for sure. Also wouln’t be suprised if there’s something specific to plane that would prevent you to do so. Tridge could confirm or not.