LinearSpring

For samples with single input/output, a locally linear spring is provided. It does not have any material and its equations are simply governed as a linear approximation

\[f(x) = k(x-x_0) + f_0,\]

where \(f\) is the force and \(x\) is the deformation measure, \(x_0\) is the deformation measure at the point about which we have linearized, and \(f_0\) is the force at that point. The force can be converted into stress/pressure by dividing by an effective area \(A_0\).

LinearSpring can be linked to other samples by “layering” them. For example, using a LayeredTube the springs acts as a Robin-type boundary condition on the next sample.