public override void UpdatePhysicalParameters()
{
base.UpdatePhysicalParameters();
// Recompute any linkset parameters.
// When going from non-physical to physical, this re-enables the constraints that
// had been automatically disabled when the mass was set to zero.
// For compound based linksets, this enables and disables interactions of the children.
if (Linkset != null) // null can happen during initialization
Linkset.Refresh(this);
}