How many milliseconds of camera-to-gyro time offset double a fused attitude error, and can online calibration recover it?
research/sensing-timesync
How many milliseconds of camera-to-gyro time offset double a fused attitude error, and can an alignment fit recover it? About 12–14 ms at 30 deg/s motion; the fit recovers it to ~1 ms with motion and fails on a still platform. Synthetic, single axis.
What it found
Single-axis simulation: a 200 Hz biased gyro and a 30 Hz camera whose timestamps are late by td, fused by a complementary filter. At 30 deg/s motion the error doubles at 12–14 ms; the doubling offset is 32–34 ms at 10 deg/s and 8–10 ms at 90 deg/s, and grows with camera noise. A gyro-integral alignment fit recovers the offset to about 1 ms rms and restores the zero-offset error, but fails on a nearly still platform. Stylised: one axis, constant offset, angle measurements only, synthetic noise.
A figure from its own output
Paper, code and results
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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.