Room modeling with complex geometries and different boundary conditions on walls

[lucpdi]

Hello,

For my research, I am working on the validation of performance and usability of different open-source room acoustics modeling software. Included in this research will be PyRoomAcoustics.

To have a reproducible result, I am using rooms from the BRAS database [source]. These are real rooms, which means that they are not necessarily shoebox shaped and could have multiple materials on one wall (for example, a hard wall with windows). I wanted to be able to model these different real world scenarios, but I was not able to find an example capable of this. Therefore, I developed by own example.

Below code is a combination of the following provided examples:

room_complex_wall_materials.py
room_from_stl.py

Furthermore, I implemented a method to assign different materials from the materials dictionary to the corresponding mesh vectors based on the build order of the mesh from the .geo file. I made sure to check the order using gmsh [source]. This method is an implementation of the suggested method from issue #260.

I wanted to provide the user the possibility to control all necessary settings, which is why I implemented these settings in the 'user input' part of the code.

After the simulation, the RIR's will be saved as .wav files. I think I developed this myself, but since it was developed a while ago I am not certain. If I missed giving anyone any credit, please post a comment and I will add this to this description.

Finally, I want to ask anyone interested to check this implementations and provide your feedback about any issues you might encounter. I want to present a reproducible and correct result in my research, which is why this is important. In addition, if you feel like you miss important user settings, please let me know so I can add this to the code.

Best, lucpdi

20250128_pra_RIR-from-stl_multiple-complex-material_v1.6.txt

@fakufaku

[coreeey]

Hi @lucpdi, could you please advise on where I can find geo/stl files for common home environments? The stl files I find online are always too complex and cannot be used properly. Additionally, besides PyRoomAcoustics, are there any other recommended open-source room acoustics modeling software?

[lucpdi]

Hi @coreeey,

I used the room from the BRAS database for my research, although I found the provided 3d models too detailed.

You could model your own rooms using Sketchup. You might also be able to model a room using the open source alternative FreeCAD, although I do not have experience using this software. I expect this might work with the script above since you can also export *.obj files from FreeCAD. If you decide to use this, I would love to hear back your experience.

If you use the above script, I would love to hear back your experience and suggestions for improving the usability.

Besides PRA you could also take a look at I-Simpa, which is another open-source room acoustics simulation software based on geometrical acoustics.

[fakufaku]

@lucpdi Thank you so much for sharing your work, and sorry for the late reply.
This is very cool, and I would be interested to add this as an example to the repository. Would you happen to have an example STL file with the materials you used? I could also add them to the repo together with the example.

[lucpdi]

Hi @fakufaku,

That's really nice! Thanks!

Please find a zip with the supplementary files below. This zip includes:

• Room model | Original Sketchup (*.skp) file, *.obj file exported from Sketchup, and the *.stl file converted from the *.obj file. The room model is a simplified version of the original from the BRAS database, available here.
• Boundary conditions | Fitted estimates from the BRAS database, available here.
• Source and receiver positions | In accordance with the original positions from the BRAS database, available here

The BRAS database also includes measurement data from the room.

I would love to hear feedback on the script.

Best, lucpdi

Supp_materials_BRAS_CR2.zip

[lucpdi]

Hey @fakufaku,

Did you manage to take a look at the script yet? What do you think of it and is it fully correct?

Thanks for your feedback!