Optimal Karting Line
TL;DR
Everything is good as long as you dont get 529 status on CC.
Intro
The GD was the one that worked best so far: https://jalcocert.github.io/JAlcocerT/kart-optimum-path/#the-results
a
under the honest κ-fix physics, the real driver is 3.35 s faster than the model says is theoretically possible. The exact numbers:
- Real fastest lap (GX020010 lap 2): 78.20 s - κ-fix N=400 honest theoretical optimum: 81.55 s
- Gap: −3.35 s (real beats the calibrated model) That doesn’t mean the driver is magically beating physics — it means the model is under-stating what the kart can actually do. Two consistent stories from today’s analyses:
- The driver is faster in both corners and straights, but more on straights: - corners: −1.08 s (driver gains 1.1 s net) - straights: −2.26 s (driver gains 2.3 s) - total: −3.35 s
- The sensitivity sweep says the model’s max_lateral_g = 0.95 is the most sensitive parameter at −27.5 s/g. Bumping it to 1.07 g (+12%) would bring the sim down to ~78 s and match your fast lap. That’s a believable correction: the calibrated 0.95 g came from yaw-rate-κ-based lap-time matching, which slightly under-counts true peaks. The sustained-vs-transient-peak distinction is exactly what Phase 4’s load-transfer model would capture.
- The pro’s 75 s sits another ~3 s below your 78.20, which the sensitivity sweep says needs another +0.12 g of lateral — total 1.19 g. That’s high-but-plausible for harder/fresher tires (the pro likely had different equipment too).
So the honest, today-as-of-now reading is:
▎ The calibrated point-mass model is slightly conservative — about 1.07 g of “true effective” lateral grip vs. the 0.95 g it has calibrated. Once Phase 4’s bicycle model captures the transient grip from load transfer, ▎ the gap to your real laps should close (and possibly close further toward the pro). The driver isn’t superhuman; the model is leaving 3 s on the table because it can’t represent trail-braking and load transfer. That’s the cleanest narrative the data supports. Sub-text: Phase 4 was the right next move — today’s evidence (real-beats-sim by 3 s, mostly explainable by transient grip the ellipse can’t represent) is exactly what richer dynamics should fix.