BeamMe (previously MeshPy) is a general purpose 3D beam finite element input generator written in Python. It contains advanced geometry creation and manipulation functions to create complex beam geometries, including a consistent handling of finite rotations. It can be used to create input files for the following finite element solvers (adaption to other solvers is easily possibly): - 4C (academic finite element solver) - Abaqus (commercial software package) - AceFEM (Finite element package for automation of the finite element method in Mathematica)

BeamMe is jointly developed at the Institute for Mathematics and Computer-Based Simulation (IMCS) at the Universität der Bundeswehr München and the Institute for Computational Mechanics (LNM) at the Technical University Munich.

• Website: https://beamme-py.github.io/beamme/
• API Documentation: https://beamme-py.github.io/beamme/api-documentation/beamme.html
• Coverage Report: https://beamme-py.github.io/beamme/coverage-report/
• Github: https://github.com/beamme-py/beamme
• Launch interactively online in Binder: https://mybinder.org/v2/gh/beamme-py/beamme/main

Overview <!-- omit from toc -->

• Examples
• How to use BeamMe?
• How to cite BeamMe?
• Work that uses BeamMe
• Installation
  • Python environment
  • Install BeamMe from GitHub (most recent version)
  • Install BeamMe from source
• Optional dependencies
  • 4C
  • CubitPy
  • ArborX geometric search
• Developing BeamMe
  • Coding guidelines
  • Testing
  • Cython geometric search
• Contributing
• Authors

Examples

Honeycomb structure under tension	Fiber reinforced composite plate
Fiber reinforced pipe under pressure	Fiber reinforcements of a twisted plate

How to use BeamMe?

BeamMe provides example notebooks to showcase its core features and functionality. The examples can be found in the examples/ directory. They can be run locally or directly tested from your browser via the following links:

• Example 1: Finite rotation framework
• Example 2: Core mesh generation functions

You can also interactively test the entire BeamMe framework directly from your browser here

How to cite BeamMe?

Whenever you use or mention BeamMe in some sort of scientific document, publication or presentation, please cite BeamMe as

BeamMe: A general purpose 3D beam finite element input generator, https://beamme-py.github.io/beamme

This could be done with the following BiBTeX entry: TeX @misc{BeamMe, author = {{BeamMe Authors}}, title = {{B}eam{M}e -- {A} general purpose {3D} beam finite element input generator}, howpublished = {\url{https://beamme-py.github.io/beamme}}, year = {YEAR}, note = {Accessed: DATE} }

Feel free to leave a ⭐️ on GitHub.

Work that uses BeamMe

Peer-reviewed articles <!-- omit from toc -->

1. Datz, J.C., Steinbrecher, I., Meier, C., Engel, L.C., Popp, A., Pfaller, M.R., Schunkert, H., Wall, W.A.: Patient-specific coronary angioplasty simulations — A mixed-dimensional finite element modeling approach. Computers in Biology and Medicine. 189, 109914 (2025). https://doi.org/10.1016/j.compbiomed.2025.109914
2. Firmbach, M., Steinbrecher, I., Popp, A., Mayr, M.: An approximate block factorization preconditioner for mixed-dimensional beam-solid interaction. Computer Methods in Applied Mechanics and Engineering. 431, 117256 (2024). https://doi.org/10.1016/j.cma.2024.117256
3. Hagmeyer, N., Mayr, M., Popp, A.: A fully coupled regularized mortar-type finite element approach for embedding one-dimensional fibers into three-dimensional fluid flow. International Journal for Numerical Methods in Engineering. 125, e7435 (2024). https://doi.org/10.1002/nme.7435
4. Steinbrecher, I., Popp, A., Meier, C.: Consistent coupling of positions and rotations for embedding 1D Cosserat beams into 3D solid volumes. Computational Mechanics. 69, 701–732 (2022). https://doi.org/10.1007/s00466-021-02111-4
5. Hagmeyer, N., Mayr, M., Steinbrecher, I., Popp, A.: One-way coupled fluid-beam interaction: Capturing the effect of embedded slender bodies on global fluid flow and vice versa. Advanced Modeling and Simulation in Engineering Sciences. 9, 9 (2022). https://doi.org/10.1186/s40323-022-00222-y
6. Steinbrecher, I., Mayr, M., Grill, M.J., Kremheller, J., Meier, C., Popp, A.: A mortar-type finite element approach for embedding 1D beams into 3D solid volumes. Computational Mechanics. 66, 1377–1398 (2020). https://doi.org/10.1007/s00466-020-01907-0

PhD thesis <!-- omit from toc -->

1. Hagmeyer, N.: A computational framework for balloon angioplasty and stented arteries based on mixed-dimensional modeling, https://athene-forschung.rz.unibw-muenchen.de/146359, (2023)
2. Steinbrecher, I.: Mixed-dimensional finite element formulations for beam-to-solid interaction, https://athene-forschung.unibw.de/143755, (2022)

Installation

Python environment

BeamMe is tested with, and supports Python versions 3.9-3.13. It is recommended to use a virtual Python environment such as Conda/Miniforge or venv. - A Conda/Miniforge environment can be created and loaded with bash # Create the environment (this only has to be done once) conda create -n beamme python=3.13 # Activate the environment conda activate beamme - A venv virtual environment can be created and loaded with (on Debian systems the following packages might have to be installed: sudo apt-get install python3-venv python3-dev) bash # Create the environment (this only has to be done once) python -m venv <path-to-env-folder>/beamme-env # Activate the environment source <path-to-env-folder>/beamme-env/bin/activate

Install BeamMe from GitHub (most recent version)

If you want to install the current main version of BeamMe directly from GitHub, simply run: bash pip install git+https://github.com/beamme-py/beamme.git@main

Install BeamMe from source

You can either install BeamMe directly from the source in a non-editable and editable fashion like: - Non-editable: This allows you to use BeamMe, but changing the source code will not have any effect on the installed package bash git clone git@github.com:beamme-py/beamme.git cd beamme pip install . - Editable: This allows you to change the source code without reinstalling the module bash git clone git@github.com:beamme-py/beamme.git cd beamme pip install -e . Now you are able to use BeamMe. A good way to get started is by going through the examples bash jupyter notebook examples/ If you also want to execute the associated test suite check out our development section.

Optional dependencies

4C

BeamMe can run 4C simulations directly from within a Python script, allowing for full control over arbitrarily complex simulation workflows. Fore more information, please have a look at the beamme.four_c.run_four_c module.

CubitPy

CubitPy is a Python library that contains utility functions extending the Cubit/Coreform Python interface. Furthermore, it allows for the easy creation of 4C-compatible input files directly from within Python. BeamMe can import meshes created with CubitPy and allows for further modification and manipulation of them.

CubitPy can be installed as an optional dependency with: bash pip install -e .[cubitpy]

ArborX geometric search

BeamMe can optionally execute its geometric search functions using the C++ library ArborX. First make sure the pybind11 submodule is loaded bash cd <path_to_beamme> git submodule update --init To setup BeamMe with ArborX, CMake and Kokkos have to be available on your system (the preferred variant is via Spack). Create a build directory bash mkdir -p <path_to_beamme>/src/build/geometric_search Configure cmake and build the extension bash cd <path_to_beamme>/build/geometric_search cmake ../../beamme/geometric_search/src/ make -j4

Note: Currently ArborX only works if BeamMe is installed in editable mode.

Developing BeamMe

If you want to actively develop BeamMe or run the test suite, you must install BeamMe in editable (-e) mode and with our optional developer dependencies ([dev,fourc]) like bash pip install -e ".[dev,fourc]" # Quotation marks are required for some shells You can now run the BeamMe test suite to check that everything worked as expected bash pytest

Coding guidelines

• When working on BeamMe, use a leading underscore (_) to indicate functions, classes, and variables that are intended for internal use only. This is a coding convention rather than an enforced rule, so apply it where it improves code clarity, especially for functions that check consistency or modify internal states.
• To avoid ambiguous or incorrect imports when using BeamMe as a library, internal imports must follow a strict aliasing convention as illustrated below:

```python # Not OK import numpy # No alias import numpy as np # Missing leading underscore

from numpy import * # Wildcard imports from numpy import core # We don't allow the import of private functionality from numpy.linalg import norm # No alias from numpy import sin as sin2 # Missing leading underscore from beamme.core.mesh import Mesh as _BeamMesh # BeamMe imports have to be aliased with the same name, i.e., should be `Mesh` (imports from third party libraries can be renamed)

# OK import numpy as _np import sys as _sys

from pathlib import Path as _Path

from math import sin as mathsin from numpy import sin as npsin

import beamme.core.conf as _conf from beamme.core.mesh import Mesh as _Mesh from beamme.core.node import Node as _Node from beamme.core.node import NodeCosserat as _NodeCosserat ```

Testing

BeamMe provides a flexible testing system where additional tests can be enabled using specific flags. The following flags can be used with pytest to enable specific test sets: - --exclude-standard-tests: Disables the default test suite - --4C: Runs tests related to 4C integration - --ArborX: Enables tests for ArborX-related functionality - --CubitPy: Runs tests for CubitPy integration - --performance-tests: Includes performance tests

These flags can be combined arbitrarily; for example, to run the 4C, CubitPy, and ArborX tests but exclude the default test suite, use: ```bash

4C Tests require a path to a 4C executable

export BEAMMEFOURCEXE=<pathto_4C>

CubitPy Tests require a path to a Cubit/Coreform installation

export CUBITROOT=<pathtoCubitor_Coreform>

pytest --4C --ArborX --CubitPy --exclude-standard-tests ```

Cython geometric search

Some performance critical geometric search algorithms in BeamMe are written in Cython. If Cython code is changed, it has to be recompiled. This can be done by running bash python setup.py build_ext --inplace

Contributing

If you are interested in contributing to BeamMe, we welcome your collaboration. For general questions, feature request and bug reports please open an issue.

If you contribute actual code, fork the repository and make the changes in a feature branch. Depending on the topic and amount of changes you also might want to open an issue. To merge your changes into the BeamMe repository, create a pull request to the main branch. A few things to keep in mind: - Read our coding guidelines. - It is highly encouraged to add tests covering the functionality of your changes, see the test suite in tests/. - To maintain high code quality, BeamMe uses a number of different pre-commit hooks to check committed code. Make sure to set up the pre-commit hooks before committing your changes bash pre-commit install - Check that you did not break anything by running the BeamMe tests. For most changes it should be sufficient to run the standard test suite: bash pytest - Feel free to add yourself to the authors section in the README.md file.

Authors

Maintainers <!-- omit from toc -->

• Ivo Steinbrecher (@isteinbrecher)
• David Rudlstorfer (@davidrudlstorfer)

Contributors (in alphabetical order) <!-- omit from toc -->

• Dao Viet Anh
• Max Firmbach (@maxfirmbach)
• Martin Frank (@knarfnitram)
• Nora Hagmeyer (@NoraHagmeyer)
• Matthias Mayr (@mayrmt)
• Gabriela Loera (@eulovi)