Hi Anton,

Did you set relative_entity_name to "ModelName::BodyName" of the reference
entity?  Without specifying relative_entity_name the pose returned will be
in the gazebo world frame.

John

On Mon, Oct 4, 2010 at 11:25 PM, Antons Rebguns <anton@email.arizona.edu>wrote:

> Hello folks,
>
> We hit what looks like a bug in implementation of get_model_state service
> in Gazebo. The scenario that we are working with is the following: imagine
> an object and a robot that is always oriented towards this objects and is
> certain distance away from it. We expect the object's position in robot's
> coordinate frame to be, let's say, 40cm away on x axis and 0 cm on y axis.
> Now if we rotate both the robot and the object by 180 degrees, we would
> expect that relative position would stay the same since robot is still
> looking straight at an object and it didn't move anywhere in relation to the
> object, but gazebo gives us -40cm on x axis and 0 on y axis. These numbers
> get weirder with different yaw angles of the robot with respect to the world
> coordinate frame. So it looks like the absolute location in the world still
> matters when getting the relative pose of one objects in some other
> coordinate frame (except 'world'). Is there something obvious that I am
> missing here?
>
> Thanks,
> Anton
>
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