Pantograph + laser scan

Train moves along +X — perpendicular to the graphite strips. Strips run along +Y (pantograph head). +Z = up. Along +X (travel): fixed laser rate → spacing Δs = v / f: low speed = closer profiles, high speed = wider apart. Vibration at f_vib Hz → wavelength along track λ = v / f: low speed = more wave cycles in the selected window, high speed = longer, smoother waves. Along +Y (strips): more km/h → more samples on inserts (× density). Heights in the model are a few mm; the viewer stretches Z (~16×) so the surface is visible, not a flat wall. Serve locally if modules fail from disk (npx serve .).

Vibration frequency (Hz)

Vertical amplitude (mm)

Tilt amplitude (mrad)

Vertical amp. jitter (%)

Tilt / direction jitter (mrad)

Train speed (km/h)

Scan window (wagons) · m

Scan density × · line rate ≈ /s

Along travel +X: Δs mm · profiles · ~ /s Δs = v / f_line. Nominal f_line ≈ 10 kHz at ×1; density × scales f (≈1.5–30 kHz). Lower speed → more profiles per window. “M of N” only if N exceeds draw cap.

Along head +Y (strips): samples — from density × below Cross-section resolution along graphite; independent of train speed.

Laser half-span on head (mm)

Insert wear (true surface, mm): cross wear and wire groove along +Y. Pits: up to six base spots; depth shared; jitter ± mm + seed shift centers (deterministic). Green boxes stay ideal.

Cross wear (arc depth) mm

Wire groove depth mm

Pit / chip depth (each) mm · count

Number of pits / chips

Pit position jitter ± mm

Pit placement seed

Pantograph + wire + mast sensor Profile polylines (laser lines) Pixel / point cloud (samples) Reconstructed surface (measured) True inserts (reference boxes) Heatmap: color = measured − true (mm)

+X = train ⊥ strips · Y = along graphite · Z = up