Rigid Body Cone
===============

A rigid body cone is a circular cone of uniform density. The cone has length defined in the X-axis, and radius for the Y- anc Z-axes, where (X, Y, Z) are the basis vectors of the body fixed frame.

**Keyword Arguments**

:param str name: Key to be used when referencing this cone.

:param str ref_point_key: Key of the point to which this cone is attached, either at its CG, aft, or forward ends.

:param str ref_frame_key: Key of the frame to which this cone orientation is defined.

:param numeric density: Uniform density of this cone.

:param numeric length: Dimension of this cone in the X-axis of the body-fixed frame.

:param numeric radius: Dimension of this cone in the Y- and Z-axie of the body-fixed frame.

:param str attach_to: CG, fore, or aft

:return str: Message about the created cone