TrueNorth is the sensor-fusion engine behind every TracQi timing number. It blends GPS, the phone's motion sensors and live vehicle data so a handset can deliver accuracy people expect from dedicated track hardware. Here are the numbers - measured, not marketed.
Positioning error (RMSE) across driving scenarios, compared to an RTK reference unit logging the same runs. Lower is better.
| Scenario | Horizontal RMSE | 95th percentile | Reference |
|---|---|---|---|
| Open circuit | 5.0 m | 8.2 m | RTK GNSS |
| Street course | 6.4 m | 11.0 m | RTK GNSS |
| Drag strip (straight) | 3.1 m | 5.4 m | RTK GNSS |
| Tree / canyon cover | 9.7 m | 17.3 m | RTK GNSS |
RMSE = root-mean-square error vs. reference track, aggregated over logged sessions. Figures represent typical results; your accuracy depends on device GPS hardware and sky visibility.
A Kalman-filter pipeline reconciles three independent sources every cycle, so a dropout in one is covered by the others.
Phone IMUs vary wildly. TrueNorth ships 90+ device profiles that pre-calibrate noise characteristics per handset, with on-device learning to refine the fit over your first few sessions.
TracQi auto-detects and speaks all nine legislated OBD2 transports, so the same adapter works across the modern fleet.
