[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Paparazzi-devel] Paparazzi Yaw channel control

From: Reto Büttner
Subject: Re: [Paparazzi-devel] Paparazzi Yaw channel control
Date: Sun, 3 Jul 2011 08:42:31 +0200

Hi Dee,

on airframes with both ailerons and rudder the standard method is to
mix some rudder to the aileron command. This reduces side slip as it
compensates adverse yaw and improves control characteristics as it
accelerates turns. The same effect can be achieved by implementing
differential deflection of the ailerons. On puller airframes you can
further reduce sideslip by mixing some rudder to the throttle command.

On aerodynamically stable airframes, like the EasyStar by Multiplex,
some people simply use the rudder as "aileron". They send the
paparazzi commands designed for the ailerons to the rudder and don't
have any ailerons on the airframe. The control quality is not very
high, but it works and in good atmospheric conditions (no turbulences)
nice flight results can be achieved. My personal experience is less
inspiring, as I failed to get satisfying control characteristics on a
Discus 2CT by Graupner using rudder only.

By actively controlling the rudder the sideslip can be neutralized in
all flight phases, in all flight attitudes and in all throttle
settings. An active control (feedback control) added to simple mixers
(feedforward control) improves control quality. Sideslip can be
measured either aerodynamically (similar to the yaw string on gliders)
or gyroscopic (similar to the bank indicator on motor planes). This is
a technically and academically interesting and challenging problem. It
might be beneficial especially for airframes with a long wing span and
a short fuselage (e.g. gliders). An implementation for paparazzi is

>From a practical, economical and reliability point of view to my
opinion the possible efficiency benefit of an active rudder control
additional to ailerons is not worth the complexity and effort. Flying
just with aileron and elevator works perfectely in all conditions and
fantastic flight results can be achieved.

Cheers, Reto

2011/7/3 Long Di <address@hidden>:
> Hello everyone,
>         the current Paparazzi flight control consists of the roll, pitch and
> throttle, I am wondering why the yaw control wasn't designed originally? For
> flying wing, the current control structure works great but for conventional
> aircraft (with rudder and elevator), a dedicated yaw control will improve
> the performance significantly. Is that necessary to add a yaw channel into
> the current architecture? (What we do know is mixing the rudder and
> ailerons)
> Regards
> Dee
> --
> (Dee) Long Di, Graduate Research Assistant
> Center for Self-Organizing and Intelligent Systems (CSOIS),
> Department of Electrical & Computer Engineering,
> Utah State University, 4120 Old Main Hill, Logan, UT 84322-4120, USA
> E: address@hidden, address@hidden T: (435)754-6787,
> W:
> _______________________________________________
> Paparazzi-devel mailing list
> address@hidden

reply via email to

[Prev in Thread] Current Thread [Next in Thread]