Robot arm

I 3d printed this robot arm I original found on Thingiverse, but the Instructable is recommended. There's a MK2, and also a delta style arm, both of which look like good alternatives, but this will do for now. Here's a video of it moving:



I've attached it to an STM32F4 Nucleo board, via a prototype shield:


In the video, I'm sending commands from a python script that runs on my desktop, communicating via USB serial. I've written an implementation of canonical s-expressions in c++ that doesn't require memory allocation, as well as a python version to talk to it. It's the main reason I haven't posted for so long, and of course overkill for just controlling some servos, but should prove more generally useful.

Here's the code. It uses platformio for the build, and mbed rtos.

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