This information is part of the Modelica Standard Library maintained by the Modelica Association.

This package contains components to model 1-dimensional translational mechanical systems, including different types of masses, external forces, spring/damper elements, frictional elements, elastogaps, elements to measure position, velocity, acceleration or the cut-force of a flange. In sublibrary Examples several examples are present to demonstrate the usage of the elements. Just open the corresponding example model and simulate the model according to the provided description.

A unique feature of this library is the component-oriented modeling of Coulomb friction elements, such as support friction. Even (dynamically) coupled friction elements can be handled without introducing stiffness, which leads to fast simulations. The underlying theory is based on the solution of mixed continuous/discrete systems of equations, i.e., equations where the unknowns are of type Real, Integer or Boolean. Provided appropriate numerical algorithms for the solution of such types of systems are available in the simulation tool, the simulation of (dynamically) coupled friction elements of this library is efficient and reliable.

A simple example of the usage of this library is given in the figure above. This model consists of a mass1 with mass m = 1 kg which is connected via a spring to a mass2 with mass m = 5 kg. The left mass is driven via an external, sinusoidal force. The filled and non-filled green squares at the left and right side of a component represent mechanical flanges. Drawing a line between such squares means that the corresponding flanges are rigidly attached to each other. By convention in this library, the connector characterized as a filled green square is called flange_a and placed at the left side of the component in the "design view" and the connector characterized as a non-filled green square is called flange_b and placed at the right side of the component in the "design view". The two connectors are completely identical, with the only exception that the graphical layout is a little bit different in order to distinguish them for easier access of the connector variables. For example, mass1.flange_a.f is the cut-force in the connector flange_a of component mass1.

The components of this library can be connected together in an arbitrary way. E.g., it is possible to connect two springs or two shafts with mass directly together, see figure below.