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3D RoboticsPermalink Reply by Chris Anderson on May 28, 2012 at 10:29pm

Rudder is coordinated with ailerons in turn. You probably won't see it work on the ground, when you're not moving. But if you tilt is far enough you should see it move enough to tell if it's going in the right direction or not.  

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Permalink Reply by criro1999 on September 4, 2012 at 4:09am

Hi Chris,

Indeed, when I tilt the plane, I can see the rudder position change. Could you please confirm that the rudder direction is OK, based on the attached files?

Thanks, Chris

Attachments:

• WP_000415.jpg, 606 KB
• WP_000416.jpg, 588 KB

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Permalink Reply by Jake Stew on May 28, 2012 at 11:36pm

You should also notice the rudder flapping around a lot when you have the plane inverted.  Also note that the elevator currently tries to smash you into the ground if you end up inverted.

I suggest not trying to fly inverted with the APM unless you really know what you're doing.

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Permalink Reply by Tom Pa on May 29, 2012 at 10:22am

Well, the rudder never moves here when rolling the fuselage while in the house no matter what mode I am in.

Jake, I do not see the actions you do when inverted. Only the elevator moves and it does it in a correct fashion to right the plane. Up elevator is given whenever the plane goes inverted.

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Permalink Reply by Jake Stew on May 29, 2012 at 12:27pm

Up elevator when inverted will do a downward loop right?  In most cases that will crash you right into the ground if you don't have a lot of altitude.  Proper way out of inverted flight is rolling out.  Just thought you should know what to expect.

When I hold my plane perfectly upside down and roll it a few degrees either way it swings the rudder fully one way or the other.  If you're getting no rudder you must have something hooked up wrong.

Check if your TX/RX in manual works the rudder properly.  If it doesn't you most likely have a wiring problem.

With the default PIDs the APM doesn't move the control surfaces by much at all in stabilize mode.  But I would check that your rudder is working a little bit at least before messing with the PID settings.

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Permalink Reply by Tom Pa on May 29, 2012 at 9:38pm

Yes the basic wiring/servos are ok. I was able to reproduce the big rudder moves when inverted by turning on rudder mix in either adruplane pid's/ other mixes/ rudder mix  or just turning rudder mix on in Standard Params/ Rudder Mix.  I turned mixing off for now, So I  am back to square one.  What does Servo Yaw Pid do??

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Permalink Reply by Jake Stew on May 29, 2012 at 11:33pm

You're not going to get rudder movement if you've turned off rudder mixing.  

Rudder mix = coordinated turn.

No rudder mix = aileron only (banking only) turn.

You probably want rudder mixing enabled if you're flying a standard 4+ channel plane.

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Permalink Reply by Andreas Breitenstein on May 30, 2012 at 3:49am

I have the rudder mix "ON" and can also not se the rudder move when I am in stabilized mode.

I am not so much concerned with the rudder not working in the turns, but more to keep my plane on track when flying a crosswind.

Will the plane track straight in "Auto" when planning a mission in crosswind? Even if the plane crabs

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Permalink Reply by Jake Stew on May 31, 2012 at 8:10am

I'm not too sure what's going on in stabilize.  There's no heading set, so I'm not sure why it would be using the rudder at all.

IME you are going to crab in auto with a cross wind.  There's not much smarts in the navigation currently.

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