I'm moving from my flybarless TREX 45 to a Raptor 90 SE with a flybar soon.
I heard that control for roll and pitch is rate based, and we have full acro control, but does stabilize mode also work?
Also, are there any general rules to consider when setting new PID's for yaw? Do the constants generally go up or down? I'll start it from scratch on a test bench, obviously, but the test bench can't handle everything, so if anyone has any pro tips, I'd owe you one.
Regards.
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Chris, have a look at this:
http://aeroden.files.wordpress.com/2011/12/helicopter_test_and_eval...
The horizontal flight stuff starts on page 22. I'm just reading through it myself.
Yes, lack of measured airspeed is a problem. Ground speed is the best we have at the moment. The problem is the airspeed would need to be airspeed and wind direction. And getting that would probably be difficult on a helicopter due to the large rotor we're under. I would think you'd need a stinger going far forward.
Hmmm... can't give you any insight into the tuning between sizes off the top of my head. Best I could do is to send you files for my 450 and 600, and you can compare and see what I ended up with.
There is no rate control on flybarless or flybarred. Stab is the only mode, and it works the same for both. The only difference is, with a flybarless, you CANNOT use Acro mode, period, it does not work, at all. With flybar, you can set the parameter H_Flybar_Mode (IIRC) to 1, which means flybarred. Now, if you use Acro mode, you will get direct stick input to swash with no gyro interference on pitch/roll, it's full manual just like the APM wasn't there.
I have tested flying in Acro mode, getting out of shape, and then flipping to Stab, and it stabilizes it well. But I wouldn't try going inverted, it can't handle that at this time.
Make that a TREX 450* Not sure why I can't edit the original post.