Improving the k-File to BRL-CAD Converter

[drossberg]

Outline

In the past years, we put some effort in the development of a LS-DYNA keyword file to BRL-CAD converter. Although we made great progress there, we still can't convert every k-file to g, i.e. the native BRL-CAD format. The goal of this project is to increase the number of covertable k-files.

Details

The sources of the current k-file to BRL-CAD converter can be found in the brlcad repository at src/conv/g. You have to compile BRL-CAD from its sources to work on this project and see the effects of your changes.

Examples of k-files, which cannot be converted with k-g, can be found here: THUMS You can however use your own examples.

Expected Outcome

We expect an improved k-g LS-DYNA keyword file to BRL-CAD converting program as the outcome from this project.

Project Properties

Skills

• C/C++
• LS-DYNA or a similar FE solver software, which can read k-files (needed as reference for how the geometry should look like)

Difficulty

medium

Size

This project could have any size, short (90h), medium (175h) or long (350h), depending on the amount of functionality you want to add.

Additional Information

• Potential mentor(s):
  Ali Haydar
  Daniel Rossberg
• Organization website: https://brlcad.org
• Communication channels: https://brlcad.zulipchat.com

[MihirGore23]

Hello @drossberg

I’m Mihir Gore, a junior at VJTI Mumbai, with experience in C++, Python, and computational geometry. I was a GSoC 2024 contributor with JdeRobot, and I’m interested in contributing to this task.

From what I understand, LS-DYNA k-files primarily store finite element (FE) mesh data, while BRL-CAD relies on constructive solid geometry (CSG). The conversion process seems to involve mapping FE-based geometries to CSG primitives, which can be non-trivial, especially for meshed surfaces. I wanted to ask—what are the major failure cases in the current converter? Are there specific LS-DYNA element types that don’t translate well into BRL-CAD’s format? Understanding these limitations would help me focus on the key areas that need improvement. Also, are there any starter tasks that I need to complete before getting hands-on with contributing and proposal drafting?

[drossberg]

Hi @MihirGore23, thanks for your interest in contributing to BRL-CAD.

Lets start with your last point: You should familiarize yourself with BRL-CAD. I.e., install the programs and go through the tutorial. Also, you should join our community chat https://brlcad.zulipchat.com. There, you can ask questions, e.g. Louis Googl about k-files. He can tell you about the issues of the current converter (mainly unhandled formats and keys in the k-files).

[AliHaider93]

Hello @MihirGore23, as @drossberg mentioned, you can join us on the Zulip chat for further discussions. I also recommend installing LS-PrePost, the pre- and post-processor for the LS-DYNA solver. Familiarizing yourself with it will help you visualize models, which can be crucial for debugging.