Osdag Internship Screening Task

Hey! This is my submission for the FOSSEE Osdag internship screening. The project involves creating 2D and 3D force diagrams (SFD and BMD) for a bridge structure.

What's Inside

Task 1: 2D Force Diagrams

Located in Osdag TASK1/

This script generates interactive 2D plots showing the Shear Force Diagram (SFD) and Bending Moment Diagram (BMD) for the central girder of the bridge. The plots include:

• Automatic peak detection with annotations
• Interactive range slider for zooming
• Clean, professional styling

To run:

cd "Osdag TASK1"
python task1_sfd_bmd.py

Output: bmd_sfd_central_girder.html (open in any browser)

Task 2: 3D Force Diagrams

Located in Osdag TASK2/

This generates 3D visualizations of the BMD and SFD for all 5 longitudinal girders. The plots use a mesh-based approach with:

• Color-coded force magnitudes
• Structural wireframe for context
• Clean, minimal axes

To run:

cd "Osdag TASK2"
python task2_3d_diagrams.py

Outputs:

• 3d_bmd_all_girders.html (3D Bending Moment Diagram)
• 3d_sfd_all_girders.html (3D Shear Force Diagram)

Setup

You'll need Python 3.7+ with these libraries:

pip install xarray numpy plotly netCDF4

Or just:

pip install -r requirements.txt

Data Files

Both tasks use screening_task.nc which contains the force data from the structural analysis. Task 2 also needs node.py and element.py for the geometry.

Notes

• All plots are interactive HTML files - you can rotate, zoom, and hover for details
• The scripts work from any directory (they find the data files automatically)
• Terminal output is kept minimal and clean

Author

Sumit Prasad
FOSSEE Osdag Internship Screening - 2026