Troubleshooting

This page lists common BobLib problems and their fixes. Most come from package loading, library versions, template selection, or baseline changes. For what each check does, see Tests and Checks.

Loading problems

OMEdit cannot find BobLib

Open the BobLib/package.mo file with File > Open Model/Library File(s). Do not open the directory. That can confuse Modelica package discovery.

If OMEdit opened an old session or a generated build directory, close it. Then open the repository package file from a clean session.

OMEdit or omc cannot find a required library

BobLib needs Modelica Standard Library 4.1.0 and VehicleInterfaces 2.0.2. Install both:

make modelica-deps

Restart OMEdit, or load the package again in a new omc session. To check the libraries by hand:

loadModel(Modelica, {"4.1.0"});
loadModel(VehicleInterfaces, {"2.0.2"});
getErrorString();

OMEdit opens but diagrams are incomplete

Load BobLib/package.mo again and check getErrorString() for missing package or class errors. On Linux, if you installed only the CLI package, install the full OpenModelica GUI package set.

Model problems

A standard template looks wrong

Check which template the entry point extends:

BobLib/Experiments/Standards/VehicleSim.mo
BobLib/Experiments/Standards/FourPostSim.mo

The templates live under BobLib/Experiments/Standards/Templates/. See Static Vehicle Templates.

If a class is missing from OMEdit or omc, check that the relevant package.order file lists the record, subsystem model, axle assembly, or template.

Animation is too heavy

Set headless = true for the run. The standard models default to headless = false, so animation geometry is on.

Full-vehicle models translate slowly

VehicleSim and FourPostSim are large multibody models. Slow translation is expected.

For repeated workflow runs, use the BobSim build targets. They reuse compiled artifacts when the inputs have not changed. Use make modelica-translation or python -m pytest Tests/test_boblib_modelica.py when you want the regression check.

Halfshaft compliance studies run slowly

Halfshaft compliance and damping are valid study parameters. More compliance detail can add faster torsional modes. When you study these effects:

• reduce the default step size or output interval
• keep the solver tolerance tight enough for the target dynamics
• confirm the adaptive solver resolves the halfshaft transient and does not step across it

Check failures

Translation failed or an equation count changed

make modelica-translation runs checkModel on the standard entry points, two regression models, and every BobLibTest fixture. The pytest node id names the failing model.

A check fails on an equation count only if its ModelCheck entry in Tests/modelica_translation_checks.py sets expected_equations. A structural change is not always wrong, but make it on purpose. If the change is expected:

1. Review the Modelica diff.
2. Confirm the model still initializes and simulates.
3. Update expected_equations in Tests/modelica_translation_checks.py.
4. Run make ci PYTHON=.venv/bin/python.

Smoke check failed

Run the package smoke check directly:

python -m pytest Tests/test_boblib_modelica.py -q

If it fails at load time, check the Modelica and VehicleInterfaces versions first. If it fails in checkModel, inspect the failing class under BobLib or BobLibTest.

Initialization baseline changed

make modelica-initialization compares fixture initialization metrics against Tests/modelica_initialization_baseline.csv.

If a model still translates but its metrics changed, inspect the affected fixture first. Regenerate the baseline only after you confirm the new state is expected:

python Tests/modelica_initialization_checks.py --update-baseline

Signal regression failed

make modelica-regression simulates selected low-level models and checks their output signals. Run the failing test directly:

python -m pytest Tests/test_modelica_regression.py -q

Then inspect the matching fixture under BobLib/ or Tests/BobLibTest/.