open source
instructions & files
License
GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007
Software
Hardware
Components: Electronics & 3D-Files (STLs)
The brain of the CAT is the BPI-Leaf-S3. The PCBs for the different modules can be ordered from JLCPCB, and other parts can be obtained from AliExpress. If you are not familiar with JLCPCB, the ordering process is explained in the video below. The STL files can be downloaded from Thingiverse.
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note:
deselect the LED from placement on the PCB



3D-Printing Settings​
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Nozzle - 0.4 mm
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Layer height - 0.2 mm, exception for keys - 0.12 mm
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All parts can be printed without support
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Infill can be based on your preference for the cat-weight (personally: I go for 5% - Lightning)
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For complicated geometry drop the printing speed of the first layer to 50%
Assembly
Electronics

Switch matrix with diodes
Diodes are included in the circuit to prevent 'ghosting' and 'blocking' issues that can occur when multiple keys are pressed simultaneously.
Circuit: Pins-Legend

Circuit: Thumb-Module

Circuit: Thumb-Module with Joystick

Circuit: Finger-Module

Circuit: Finger-Module with Scroll Wheel

Circuit: Mouse Module

Circuit: Gyroscope Module

Firmware for the CAT
The firmware is written in PaltformIO (setup tutorial) with following options:
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platform -> espressif32
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board -> bpi_leaf_s3
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framework -> arduino
Software for key assignment - LYNXapp
Assembly Tutorial
Future of the project
Here is a list of the next features and improvements.
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Trackball module
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Wireless Connection
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optimizing the form and design for different hand sizes
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web game to accelerate the adaption
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If you are interested in being a part of the LYNXproject, please visit the Join the Team page.
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