This is probably if the other end of the spring element is not connected to a real element with mass (bar, shell, solid) as it takes its mass from that.
If this is connected just to a grounding point which is constrained or to an RBE2 (which is not a nodal rigid body FULLRIG), then you can add a dummy mass point (CONM2) to that node.
This is probably if the other end of the spring element is not connected to a real element with mass (bar, shell, solid) as it takes its mass from that.
If this is connected just to a grounding point which is constrained or to an RBE2 (which is not a nodal rigid body FULLRIG), then you can add a dummy mass point (CONM2) to that node.
