<element name="spherical_coordinates" required="0">
<element name="surface_model" type="string" default="EARTH_WGS84" required="1">
<description>
Name of planetary surface model, used to determine the surface altitude
at a given latitude and longitude. The default is an ellipsoid model of
the earth based on the WGS-84 standard. It is used in Gazebo's GPS sensor
implementation.
</description>
</element>
<element name="world_frame_orientation" type="string" default="ENU" required="0">
<description>
This field identifies how Gazebo world frame is aligned in Geographical
sense. The final Gazebo world frame orientation is obtained by rotating
a frame aligned with following notation by the field heading_deg.
Options are:
- ENU (East-North-Up)
</description>
</element>
<element name="latitude_deg" type="double" default="0.0" required="1">
<description>
Geodetic latitude at origin of gazebo reference frame, specified
in units of degrees.
</description>
</element>
<element name="longitude_deg" type="double" default="0.0" required="1">
<description>
Longitude at origin of gazebo reference frame, specified in units
of degrees.
</description>
</element>
<element name="elevation" type="double" default="0.0" required="1">
<description>
Elevation of origin of gazebo reference frame, specified in meters.
</description>
</element>
<element name="surface_axis_equatorial" type="double" default="0.0" required="0">
<description>
Equatorial axis of a custom surface type, specified in meters.
This is only required for custom surfaces.
</description>
</element>
<element name="surface_axis_polar" type="double" default="0.0" required="0">
<description>
Polar axis of a custom surface type, specified in meters.
This is only required for custom surfaces.
</description>
</element>
<element name="heading_deg" type="double" default="0.0" required="1">
<description>
Heading offset of gazebo reference frame, measured as angle between
Gazebo world frame and the world_frame_orientation type.
The direction of rotation follows the right-hand rule, so a positive
angle indicates clockwise rotation (from east to north) when viewed from top-down. Note
that this is not consistent with compass heading convention.
The angle is specified in degrees.
</description>
</element>
</element>