AstroTouch

AstroTouch transforms astronomical FITS images into 3D-printable STL relief models. Designed primarily for astronomy outreach for the blind and visually impaired (BVI), it allows anyone to feel the universe by turning brightness data into tactile contours.

AstroTouch Desktop GUI

AstroTouch features a powerful, interactive desktop application that lets you preview and customize your 3D models in real-time.

GUI Features

• Real-time 3D Preview: View your model immediately after generation.
• Tactile Labeling: Add custom raised text or Unified English Braille (UEB) labels.
• Dedicated Label Areas: Extend the model base to create a flat, easy-to-read surface for labels.
• Interactive Controls: Adjust scaling, clipping, smoothing, and borders with instant feedback.
• One-Click Save: Export your finalized model directly to STL.

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Key Engine Features

• UEB Braille Support: Fully compliant Unified English Braille translation, including capitalization indicators and punctuation.
• Smart Scaling: Choose between Linear, Logarithmic, or Arcsinh scaling to bring out the best detail in your data.
• Auto-HDU Detection: Smartly identifies the correct 2D image data within complex multi-extension FITS files.
• Tactile Optimization: Built-in Gaussian smoothing and clipping to ensure models are comfortable to touch and easy to print.
• High Performance: Vectorized mesh generation engine for rapid processing of high-resolution images.

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Installation

Prerequisites

• Python 3.8 or higher.
• A 3D printer (or a slicer like Cura/PrusaSlicer to view the models).

Steps

1. Clone the repository:

   git clone https://github.com/enzoperesafonso/AstroTouch.git
   cd AstroTouch

2. Install dependencies:

   pip install -r requirements.txt

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Usage

Desktop GUI

Launch the interactive interface:

python gui.py

Command Line Interface (CLI)

For batch processing or advanced workflows:

python cli.py input.fits [output.stl] [options]

CLI Parameters

Argument	Type	Default	Description
input	Path	(Required)	Path to the input FITS file.
output	Path	input.stl	Path to the output STL file.
--hdu	Int	Auto	HDU index containing the 2D image data.
--longest-side	Float	None	Scale the longest side of the image content to this size in mm.
--max-height	Float	10.0	Maximum height of astronomical features above the base (mm).
--base-thickness	Float	2.0	Thickness of the solid base plate (mm).
--clip	Float	1.0	Percentile to clip outlier pixels (e.g. 1.0 clips top/bottom 1%).
--smooth	Float	0	Gaussian smoothing sigma in pixels (e.g. 1.5).
--downsample	Int	1	Factor to reduce image resolution (e.g. 2 halves dimensions).
--nan-value	Float	Min	Value to replace NaNs with.
--log	Flag	False	Apply log(1+x) scaling (ideal for high dynamic range).
--asinh	Flag	False	Apply arcsinh scaling (common in astronomical imaging).
--invert	Flag	False	Invert heights (brightest pixels become lowest points).
--border-width	Float	0.0	Width of a raised frame around the model (mm).
--border-height	Float	0.0	Height of the border frame above the base (mm).
--label	String	""	Custom text for the tactile label.
--label-mode	String	text	Style of label: text or braille.
--label-depth	Float	1.5	Height/thickness of the raised label characters (mm).
--label-size	Float	5.0	Font size/scale of the label characters (mm).
--label-area	Float	0.0	Width of dedicated flat area at the bottom for the label (mm).
--verbose	Flag	False	Enable detailed logging.

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Example Workflow: Helix Nebula

This example demonstrates how to create a high-quality tactile plaque of the Helix Nebula.

1. Command: Generate a 120mm plaque with logarithmic scaling, a protective border, and a UEB Braille label in a dedicated area.

   python cli.py helix.fits helix_tactile.stl \
     --longest-side 120 \
     --log \
     --clip 1 \
     --smooth 1.5 \
     --border-width 5 \
     --border-height 2 \
     --label "Helix Nebula" \
     --label-mode braille \
     --label-area 15

2. Result: The engine produces an STL file with a 120mm core, a 5mm frame, and a 15mm flat section at the bottom containing the Braille dots for "Helix Nebula".

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Project Structure

• gui.py: Desktop GUI launcher.
• cli.py: Command Line Interface launcher.
• src/astrotouch/: Core logic and UI source code.
• assets/: Documentation images and example data.
• tests/: Verification scripts.

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Motivation

Astronomical data is overwhelmingly visual. This project aims to bridge the gap by providing a tool to create tactile representations of celestial objects and data, making astronomy more accessible and engaging for individuals who are blind or visually impaired. By feeling the contours, peaks, and valleys corresponding to stars, nebulae, and galaxies, users can gain a different understanding of astronomical structures.

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License

This project is licensed under the MIT License - see the LICENSE file for details.

By Enzo Peres Afonso (2025).