Go2Kin

• Equipment
• First-time setup
• Regular use
• GUI reference
• Known issues & tips

Work in progress

Go2Kin and this manual are under active development.

Go2Kin is an integrated markerless motion capture pipeline for up to 4 USB-wired GoPro cameras, run from a single desktop GUI.

It covers the full workflow of a traditional marker-based lab (e.g. Vicon Nexus): - camera connection and setup (Open GoPro HTTP API over USB), - camera calibration (adapted from Caliscope), - recording and auto-sync in post processing (hand claps or an LED flash), - pose estimation (RTMpose), triangulation, filtering, interpolation (Pose2Sim), - 3D kinematics (OpenSim).

The code was designed to be modular so blocks can be swapped in/out; e.g. change the camera connection/handling block to use different cameras / conenction method (e.g. WiFi), change pose estimtion to use e.g. some vision transformer instead of CNN-based method, etc.

It is also designed mainly for indoor labs, and several design choices follow from that setting:

• USB-wired cameras for simple reliable connection,
• Audio-based synchronisation using hand claps - simple and robust indoors,
• or, hands-free, LED light sync - an LED flash seen by all cameras, unaffected by room noise or camera distance.

Developed and tested with the GoPro Hero 12 Black on Windows 11; any GoPro supporting the HTTP API (Hero 9 or later) should work.