So i am almost done with my schematic. I just need to do some finishing touches and check the ERC. then I can start with my PCB!
Working on the first stages of the Schematics for the PCB
Dum-E is my Iron-Man-inspired robotic arm: 3 axes plus a gripper, 4 servos in total. This week I opened KiCad for the first time and designed the full schematic for its custom control board. The brain is a Seeed XIAO ESP32-S3 running CircuitPython. It talks over I2C to a PCA9685 16-channel driver that runs all the servos. For manual control there are 4 potentiometers and 3 buttons, powered by a dedicated 5-6V supply with a 1000uF cap to smooth out servo current spikes. ERC is now fully clean. Next up: footprints and the PCB layout.
Just finished setting up my account, converting stl files to .step ones and I added a demo URL to my project.
Finished my LG Hackpad! 🎉
This is a 9-key mechanical macropad with a rotary encoder and an OLED display, built around the Seeed XIAO RP2040.
What I did:
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Designed the schematic and the 2-layer PCB completely from scratch in KiCad (my first PCB ever!). Hand-routed the switch matrix with per-key 1N4148 diodes, added a GND pour and fitted everything under 100x100mm (final: 68x99.68mm).
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Designed the case in Tinkercad: an open tray design with the XIAO RP2040 exposed, an anti-flex support grid under the PCB, USB cutout and 4x M2 standoffs - printable without supports.
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Built the firmware (CircuitPython): the encoder browses through profiles on the OLED, and each of the 9 keys is freely configurable via a JSON config.
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Made a desktop configurator app (Python + CustomTkinter) to assign key combos or custom scripts to every key.
Biggest challenge as a first-timer: hand-routing a 2-layer board without crossing nets while keeping a clean GND pour. Super happy
with how it turned out!
