Abstract
A method for race and lap timing to tell which layout of a track a vehicle drove on each lap, and whether the lap was clean, using only a yaw-rate gyro and accelerometer on the vehicle and the times it crossed a timing line. It needs no satellite positioning, so it is meant to work indoors too. Between two crossings, the vehicle cuts its yaw-rate trace into corners and records each corner's signed angle. Where a corner has a straight before and after it, the track sets both headings, so the corner turns through close to the same angle whatever line is taken. Each lap is matched by edit-distance alignment against the venue's layouts, which are learned by clustering laps and named once by staff. The same data reveals cut corners and spins (a slow half-spin isn't flagged, and usually leaves the lap as an unknown layout), and lateral acceleration divided by yaw rate estimates each corner's speed. In simulation, with the gyro offset estimated at standstill, it identified 358 of 360 laps on six closed layouts sharing one line (2,511 of 2,520 over seven seeds, none given the wrong layout), against 216 from lap time alone, and 549–567 of 592 laps on 74 Australian track outlines mapped in OpenStreetMap, with 0–3 assigned to the wrong track. The limits and the simulation code are included.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
James, River, "Identifying the track layout and checking laps from a vehicle's yaw-rate gyro, without satellite positioning", Technical Disclosure Commons, (October 20, 2026)
https://www.tdcommons.org/dpubs_series/12332
Python simulation code behind section 6 (appendix A of the PDF); needs numpy and scipy