[...]
> I was looking at your driver docs and noticed a bit of nonstandard
> coordinate frames going on. First, see
> http://www.ros.org/reps/rep-0103.html for an overview of how
> coordinate systems are defined in ROS. Body frames are generally
> defined as +X forward, +Y left and +Z up. In that case, what you do
> with the Twist is a bit non-standard; linear.x should be forward/back,
> linear.y would be left/right and linear.z would be up/down, with
> angular.z as yaw if the AR.Drone's body frame was following the
> standard ROS convention for coordinate systems. Any reason why you
> went with the Twist interpretation as documented on the wiki at
> http://www.ros.org/wiki/ardrone_driver as opposed to a more standard
> interpretation?
>
Hi,
Actually, the standard coordinate frame for flying system is with Z down
(it allows standard compass angle to be coherent with the X,Y motion).
For this reason,
I'm voting in favour of a Z down coordinate system for the AR-Drone.
However, I agree that I would be suprised without x forward, y
sideways, and yaw around z....
As soon as we have velocity control on the CoaX helicopter, our control
will definitely be like that.
Best regards
--
Dr. Cedric Pradalier
http://www.asl.ethz.ch/people/cedricp
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