How much motion does a camera-to-gyro offset fit need, and what does clock skew do to a one-off calibration?

What it found

Same single-axis gyro and camera world as sensing-timesync, with the camera stamp error growing as t_d = t_d0 + skew·t. An alignment fit recovers a 20 ms offset within 5 ms in 8 of 8 runs at 16 deg/s or more, but only 2 of 8 at 1 deg/s and 0 of 8 at 0.3 deg/s. A camera clock 1000 ppm fast raises attitude error from 0.152 to 0.514 deg uncorrected and 0.254 deg after a fixed-offset fit, while fitting offset and skew together gives 0.155 deg up to 2000 ppm; skew recovery needs a window of about 40 s. Stylised: one axis, linear skew, synthetic noise, skews exaggerated to show an effect in 40 s.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.