The collision properties of a link. Note that this can be different from the visual properties of a link, for example, simpler collision models are often used to reduce computation time. Unique name for the collision element within the scope of the parent link. intensity value returned by laser sensor. Maximum number of contacts allowed between two entities. This value overrides the max_contacts element defined in physics. Mass Density of the collision geometry. This is used to determine mass and inertia values during automatic calculation. Default is the density of water 1000 kg/m^3. Parent tag to hold user-defined custom params for mesh inertia calculator