XArray Constructor

A calculator that simplifies the design of X-ray baggage scanner geometry.
It allows you to parameterize the X-ray tube, detector cards, and the scanning plane structure, including the detector array.
The program outputs the precise positions of detectors within the array, along with the coordinates of their mounting platforms.
Using this data, you can design a detector array that enables your scanner to produce geometrically flawless images.

Installation:

git clone https://github.com/kdmitruk/xarray_constructor.git
cd xarray_constructor
pip install -r requirements.txt

How to use:

Prepare configuration files for the X-ray tube and detector card.
Run the program with the path to your scanner configuration file:

python arr_constructor.py scanners/scanner_name.json

If you want to create a new scanner configuration, the best way is to modify an existing scanner file.
All scanner parameters can be adjusted through the graphical interface.
A realtime scanner visualization is displayed, allowing you to verify the layout interactively. Detector card and X-ray tube details can only be modified by editing their respective files, as they are not meant to change frequently.
All device description files use the JSON format.

Benchmark

The --benchmark option allows for the measurement of model calculation time and plotting time. A benchmark.json scanner configuration is available that is large enough to be used for benchmarking.

Tube file

The X-ray tube file describes its dimensions and the position of the focal spot inside the tube.
The tube emits fan-shaped radiation whose angular range is parameterized.
To maintain consistency with the technical drawings typically used by tube manufacturers, it is assumed that zero degrees corresponds to the vertical (Z-axis) direction.
Angles are measured in degrees.

Tube configuration files are located in the tubes directory.

parameter	description
size_x	Tube case width
size_z	Tube case height
focal_spot_x	Distance from the left border of the tube case to the center of the focal spot
focal_spot_z	Distance from the bottom border of the tube case to the center of the focal spot
start_angle	Left boundary angle of the radiation fan. Use negative values for counterclockwise angles.
angle	Total clockwise angle of the radiation fan, starting from the start_angle

Detector card file

The detector card file describes a single building block of the detector array.
The starting point is defining the dimensions of the PCB (printed circuit board) on which the card is built.
The position and dimensions of the photodiode, which registers radiation, are defined relative to the PCB.

The list of platforms defines where in 3D space the supports for the detector card are placed.
The bottom margin shifts the photodiode upward from the array base, leaving space for components such as cables.

Detector card files are located in the cards directory.

parameter	description
plate_size_x	Width of the detector card
plate_size_y	Length of the detector card
photodiode_offset_x	Distance from the left edge of the detector card to the photodiode
photodiode_offset_y	Distance from the top (Y-axis) edge of the detector card to the center of the photodiode
photodiode_offset_z	Distance from the bottom (Z-axis) edge of the detector card to the bottom of the photodiode
photodiode_size_x	Length of the photodiode
photodiode_size_y	Width of the photodiode
bottom_margin	Margin between the bottom of the photodiode and the bottom of the array. Useful if the detector card includes cables or other elements below the photodiode.
platforms	List of supporting platform positions. Each entry specifies:
platforms[].y	Position along the length of the detector card (measured from the top edge)
platforms[].z	Height of the platform relative to the bottom of the detector card. Use this if platforms have different heights.

Scanner file

The scanner file describes the relative positions of all scanner components.
The reference point for most dimensions is position (0, 0).

The tube and detector card models are referenced by file names from their respective directories (without .json).
The tube can be tilted using the tube.shift_z parameter.

The program assumes that the tube is positioned below the tunnel, while the detector array surrounds the tunnel on one to three other sides.
The case and tunnel allow for visual assessment of element positions but do not affect calculations.

Scanner configuration files are located in the scanners directory.

parameter	description
array	Parameters of the detector array
array.mode	Array configuration mode. Options: compact or arc. Arc mode disables the left and right arms of the array.
array.offset_x	Horizontal offset of the array
array.offset_z	Vertical offset of the array
array.length	Length of the top part of the detector array
array.height	Height of the top part of the detector array
array.bottom_thickness	Thickness of the array’s bottom plate. Used as an additional placement margin for detector cards.
array.initial_card_offset	Offset of the first detector card. Use for fine-tuning the card alignment. Do not exceed the width of a single detector card.
array.left_side	Parameters of the detector array’s left arm
array.left_side.enabled	Whether the array’s left arm is present
array.left_side.length	Length of the array’s left arm
array.left_side.height	Height of the array’s left arm
array.right_side	Parameters of the detector array’s right arm
array.right_side.enabled	Whether the array’s right arm is present
array.right_side.length	Length of the array’s right arm
array.right_side.height	Height of the array’s right arm
tube	X-ray tube parameters
tube.model	Model of the X-ray tube. Use the name of a file from the tubes directory
tube.offset_x	Horizontal offset of the tube’s bottom-left corner
tube.offset_z	Vertical offset of the tube’s bottom-left corner
tube.shift_z	Vertical offset of the tube’s bottom-right corner relative to its bottom-left corner
card	Detector card parameters
card.model	Model of the detector card. Use the name of a file from the cards directory
tunnel	Scanner tunnel parameters
tunnel.offset_x	Horizontal offset of the tunnel
tunnel.offset_z	Vertical offset of the tunnel
tunnel.size_x	Width of the tunnel
tunnel.size_z	Height of the tunnel
case	Protective casing parameters
case.offset_x	Horizontal offset of the case
case.offset_z	Vertical offset of the case
case.size_x	Width of the case
case.size_z	Height of the case

Output:

The application allows exporting the results of its calculations as a JSON file, which includes the locations of the platforms supporting the detector card, as well as the positions of the photodiodes. It is also possible to generate a scene file for the simulation, which is described here.

License

This project is licensed under the GPLv3 License.
See the LICENSE file for details.

Author

Developed by Krzysztof Dmitruk.