gcs is a Python library for creating generalized cylindrical shells (GCS).

GCS are parameterized by 11 values:

Syntax	Description
c4_base	The parameter controlling the size and shape of the base $4$-lobe feature.
c8_base	The parameter controlling the size and shape of the base $8$-lobe feature.
c4_top	The parameter controlling the size and shape of the top $4$-lobe feature.
c8_top	The parameter controlling the size and shape of the top $8$-lobe feature.
twist_linear	The rotation (rad) of the top. This creates a linear twist between the base and top.
twist_amplitude	The amplitude (rad) of the oscillating twist between the base and top.
twist_cycles	The number of cycles of the oscillating twist between the base and top.
perimeter_ratio	The ratio between the top and base perimeters.
height	The height (mm).
mass	The mass (g).
thickness	The wall thickness (mm).

c4 and c8 Relationship

• Adopted from Overvelde and Bertoldi, 2014

twist_linear, twist_amplitude, and twist_cycles Relationship

Download

gcs requires Python version 3.8 (or higher). To install, run the command:

pip install gcs-shape

Requirements

• bentley-ottmann (version: 7.3.0)
• mapbox_earcut (version: 1.0.0 or higher)
• numpy (version: 1.21.5 or higher)
• numpy-stl (version: 2.17.1 or higher)
• pandas (version: 1.4.1 or higher)
• scipy (version: 1.7.3 or higher)

Supported Operating Systems

gcs is operating system independent. The package has been tested on the following operating systems:

• MacOS Ventura 13.4.1
• Ubuntu 22.04
• Windows 10

Quickstart

import gcs

# Create a generalized cylindrical shell
shape = gcs.GCS(c4_base=0.3,
                c8_base=-0.2,
                c4_top=0.4,
                c8_top=-0.3,
                twist_linear=2,
                twist_amplitude=0.05,
                twist_cycles=3,
                perimeter_ratio=1.5,
                height=20,
                mass=2.1,
                thickness=0.48)

# Assert the shape is valid
print(shape.valid)

# Save shape to STL file
gcs.io.save_mesh(file='shape.stl', shape=shape)

Contributing

The contribution guidelines can be found in CONTRIBUTING.md.

Maintainers

• Sam Silverman - sssilver@bu.edu

Citation

@article{Snapp:2024:SuperlativeMechanicalEnergy,
author={Snapp, Kelsey L. and Verdier, Benjamin and Gongora, Aldair E. and Silverman, Samuel and Adesiji, Adedire D. and Morgan, Elise F. and Lawton, Timothy J. and Whiting, Emily and Brown, Keith A.},
title={Superlative mechanical energy absorbing efficiency discovered through self-driving lab-human partnership},
journal={Nature Communications},
year={2024},
month={May},
day={21},
volume={15},
number={1},
pages={4290},
issn={2041-1723},
doi={10.1038/s41467-024-48534-4},
url={https://doi.org/10.1038/s41467-024-48534-4}
}