Modelica Standard Library

The workbench ships with the Modelica Standard Library 4.1.0: Modelica, ModelicaServices and Complex appear in the package browser next to the bundled Daedalus library, with nothing to install. On the command line, pass an MSL checkout as extra sources (see Command line).

#Coverage

473 of the 534 MSL 4.1.0 example models translate and simulate to the end, and 424 of them match the Modelica Association's reference results (see below). They include:

• Mechanics (Rotational, Translational, MultiBody), Electrical (Analog, Digital, Machines, QuasiStatic machines, PowerConverters, Batteries), Thermal, Blocks, StateGraph and clocked synchronous models;
• Modelica.Media: IF97 water, R134a, ideal-gas mixtures, moist air and reference air, through compiled run-time functions with exact partial derivatives;
• most Modelica.Fluid systems;
• ModelicaStandardTables lookups, replaced by native tables with linear, constant, Akima and Fritsch–Butland smoothness, hold, linear and periodic extrapolation, and time events at breakpoints.

The remaining failures, and what is being done about them, are listed in the Roadmap.

#Checked against the reference results

Simulating is not enough: the results have to be right. A nightly CI job simulates every MSL 4.1.0 example and compares its comparison signals with the Modelica Association's reference results (MAP-LIB_ReferenceResults, generated with Dymola), and fails if a model that passed in the committed baseline stops passing.

The scoreboard lists every example with its status, the signals that differ and the error text, with a link to open it in the workbench.

The baseline is docs/conformance/msl-4.1.0.json, made by tools/refcompare.py.

#Examples to try

Each link opens the model in the workbench; press ▶ Simulate.

#Rotational mechanics: CoupledClutches

Four inertias coupled by three clutches that open and close at set times: a classic test of friction events, stuck and sliding phases.

Open Modelica.Mechanics.Rotational.Examples.CoupledClutches

#Analog electronics: ChuaCircuit

A chaotic oscillator. The second subplot plots C2.v against C1.v to show the double scroll attractor.

Open Modelica.Electrical.Analog.Examples.ChuaCircuit

#Control: PID_Controller

A drive train under a PI speed controller, following a kinematic reference profile while a load step hits it.

Open Modelica.Blocks.Examples.PID_Controller

#Heat transfer: TwoMasses

Two masses at different temperatures that equalize through a thermal conductor.

Open Modelica.Thermal.HeatTransfer.Examples.TwoMasses

#MultiBody: DoublePendulum

Two bodies on revolute joints, with the 3-D animation that every MultiBody result gets.

Open Modelica.Mechanics.MultiBody.Examples.Elementary.DoublePendulum

For full vehicle models built on MultiBody, see Multibody vehicles.

#How the browser loads it

The MSL sources are not in the repository. At build time, web/scripts/fetch-msl.mjs downloads the v4.1.0 release from GitHub and packs its .mo and package.order files into one gzip bundle (about 2.6 MB; 14.8 MB unpacked) with a content hash in its name. The workbench downloads it after the Daedalus library, unpacks it with DecompressionStream, and registers every file without parsing it. A light token scan outlines each file so the package browser lists the whole library within seconds, and a class is parsed only when it is opened, checked or simulated, together with the classes it needs.