Re: [Paparazzi-devel] Question about throttle control for fixed-wing aircrafts

[Loic Drumettaz]

Hi,

If measured pitch is higher than setpoint we should add down elevator. So I suppose down elevator is negative here. That's only a matter of sign conventions. 

I recommend to use stabilization_adaptive instead of stabilization: not because of the "adaptive" terms (that i never tried) but because of integral term in the pitch and roll control loops.

This reduces static error.

See: http://wiki.paparazziuav.org/wiki/Fixedwing_Configuration

Regards

Loïc

2014-08-14 17:22 GMT+02:00 wertrrte <address@hidden>:

Loic,thanks for your reply!

Your advice is so helpful and I will follow it.

Since you know so well about the control loops,I'd like to ask another
question,sorry for bothering you so much.

In the pitch loop (in stabilization_attitude.c,fixed-wing),comparing to the
code,there is one sentence:

float cmd = -h_ctl_pitch_pgain * (err + h_ctl_pitch_dgain * d_err);

So,why the  '-' ?  If real pitch is bigger than the expected,we should add
positive value to the elevator so

the plane's pitch will be smaller and the err can be eliminated.Isn't it?
Why is the '-' used?

wertrrte



--
View this message in context: http://lists.paparazziuav.org/Question-about-throttle-control-for-fixed-wing-aircrafts-tp15982p15987.html

Sent from the paparazzi-devel mailing list archive at Nabble.com.

_______________________________________________
Paparazzi-devel mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/paparazzi-devel