A physical link with inertia, collision, and visual properties. A link must be a child of a model, and any number of links may exist in a model. A unique name for the link within the scope of the model. If true, the link is affected by gravity. If true, the link can collide with other links in the model. If true, the link is kinematic only This is the pose of the link reference frame, relative to the model reference frame. Exponential damping of the link's velocity. Linear damping Angular damping