Session Logs

While built-in smartphone GPS receivers typically update coordinates at 1Hz to 5Hz, MyLapLog overcomes discrete hardware limitations using sub-sample linear time interpolation and a 2D vector cross-product line intersection algorithm to deliver millisecond-accurate timing.

The algorithm calculates the exact intersection ratio (α) between the vehicle trajectory vector spanning the points immediately before (P1, t1) and after (P2, t2) the start/finish gate line (A–B) using real-time simultaneous vector equations: This reconstructs the exact instant the vehicle physically crossed the timing line down to 0.001s, independent of hardware polling intervals. A perpendicular heading gate filter (±45°) and Haversine distance threshold eliminate false triggers from nearby pit-lane rollouts or paddock movement. External high-rate Bluetooth GPS receivers (10Hz–25Hz) are also natively supported for ultra-high-resolution telemetry.

MyLapLog automatically detects the instant a vehicle crosses the pit-entry and pit-exit geofence gates using real-time vector crossing calculations.

1. Mandatory Pit-Stop Regulation Timer: Upon crossing the pit-entry line, a visual and acoustic HUD countdown initiates immediately, pre-configured to motorsport championship regulations (such as Hyundai N Festival, Superrace, or endurance trackday series).
2. Stationary vs Transit Separation: By evaluating GPS velocity thresholds (v < 3.0 km/h) combined with vehicle acceleration data, MyLapLog splits total pit duration into Stationary Box Time (driver swaps, tyre pressure checks, wheel changes) and Pit Transit Time (rolling through the speed-limited pit lane) with 0.1s precision.
3. Pit-Lane Speed Limit Alerts: Visual and audio warnings activate instantly if the vehicle exceeds the circuit pit-lane speed limit (typically 60 km/h), mitigating penalty risks.

MyLapLog outputs telemetry strictly in compliance with the Racelogic VBOX file specification for seamless integration with Racelogic Circuit Tools 3.

1. Dedicated Channel Header Architecture: Files are strictly partitioned into [header], [channel units], [comments], and [data] sections. Coordinates are converted to the standard NMEA-derived DDMM.MMMMM format expected by Circuit Tools.
2. Uniform 10Hz Telemetry Stream: Timestamps, latitude, longitude, velocity (km/h), heading (0–360°), altitude (m), vertical velocity, and satellite count are cleanly serialised at 10Hz.
3. Symmetrical Gate Pair Calibration: To prevent split-line interpolation discrepancies in Circuit Tools, MyLapLog generates a calibrated gate pair (±1.0m, ±20ms) straddling the start/finish line. This guarantees 0.000s timing variance (perfect synchronization) between the live web timer readout and post-session Circuit Tools desktop analysis.

MyLapLog is architected specifically for demanding motorsport environments, featuring a Progressive Web App (PWA) offline engine and the W3C Screen Wake Lock API.

1. Complete Offline Buffering: All GPS telemetry acquisition, gate intersection calculations, lap timing logic, and 10Hz data streaming execute entirely inside the browser's client-side JavaScript engine and IndexedDB / LocalStorage persistence layers. The platform operates flawlessly in cellular blackspots without any internet connection.
2. Continuous Display Wake Lock: The Screen Wake Lock API keeps your device display active throughout your stint, preventing automatic sleep or dimming. In addition, the Web Audio API frequency synthesiser generates split-second audio lap beeps locally with 0ms latency, independent of network status.