NAVEE

Articles, guides, and products tagged "NAVEE" — a combined view of every catalogue resource on this topic.

User guide

Aerodynamics of an electric scooter as an engineering discipline: F_drag = ½·ρ·v²·CdA, decomposition into pressure/friction/induced/interference, Reynolds regimes (rider Re ≈ 10⁶, wheel Re ≈ 6×10⁴), CdA breakdown (rider 60-75% + frame 10-15% + wheels 5-10% + bag 0-15%), measurement methods (wind tunnel + coastdown ISO 10521 + power-meter Martin 1998), yaw-angle dependence Cy, why wheel aero on 8-10" differs from bike/moto, body-position tradeoffs vs stability, P_drag > P_roll crossover ≈ 19 km/h, fairings engineering and EU L1e, vehicle-class CdA table

Why a standing upright rider posture on an e-scooter is the worst CdA configuration among all personal vehicles (typical 0.55-0.70 m²), and why that means drag power begins to dominate rolling resistance from just 18-22 km/h — whereas a tucked motorcyclist only reaches that crossover at ~50 km/h. This article does not repeat the user-facing wind protocol from [Riding in windy weather](@/guide/riding-in-wind.md) and is not the same as the [energy-budget model](@/guide/real-world-range-energy-budget.md) — it is the **engineering foundation under both**: the formal drag equation F_drag = ½·ρ·v²·CdA with decomposition into pressure/friction/induced/interference, Reynolds regimes for the rider (L ≈ 1.7 m → Re ≈ 10⁶ at 25 km/h: turbulent boundary layer) and wheel (R ≈ 0.1 m → Re ≈ 6×10⁴: subcritical regime, drag crisis Re ≈ 3×10⁵ unreachable); CdA breakdown by component (rider 60-75% of frontal silhouette 0.4-0.55 m² + frame/deck 10-15% + wheels 5-10% + bag/cargo 0-15%), extrapolated from Crouch et al. 2017 J. Fluids and Structures 74:153-176 cycling aerodynamics state-of-the-art review and Bert Blocken et al. (TU/e + KU Leuven) bicycle-pose CFD studies; three measurement methods (wind tunnel low-speed automotive Eppler-section; coastdown ISO 10521-1:2015 + SAE J1263/J2263; power-meter regression Martin et al. 1998 J. Applied Biomechanics 14(3):276-291) with accuracy bands; yaw-angle dependence — Cy reaches 0.6-0.8 at 15-20° yaw, explaining catastrophic crosswind behaviour; wheel aerodynamics on small 8-10" wheels — why disc-vs-spoke difference is <2% drag (vs ~5% on 700c bike wheels) because of small frontal area; body-position tradeoffs — tucked posture possible but constrained by deck length and vibration absorption; power crossover P_drag > P_roll for CdA 0.55 + Crr 0.012 + m_total 105 kg at v ≈ 19 km/h (below it P_roll dominates, above it cubic P_drag dominates); fairings engineering — CdA reduction potential 25-40%, but crashworthiness penalty + EU L1e enclosure rules; vehicle-class CdA table for context (cyclist tucked 0.20-0.25; cyclist upright 0.45-0.55; e-scooter rider 0.55-0.70; motorcyclist tucked 0.30; auto 0.6-0.8). ENG-first sources (0 RU): Wilson «Bicycling Science» 4th ed. MIT Press 2020; Martin et al. 1998 J. Applied Biomechanics 14(3):276-291; Crouch et al. 2017 J. Fluids and Structures 74:153-176; Blocken et al. TU/e + KU Leuven cycling CFD; Hoerner «Fluid-Dynamic Drag» 1965; ISO 10521-1:2015; Anderson «Fundamentals of Aerodynamics» 6th ed. McGraw-Hill 2017; Schlichting & Gersten «Boundary-Layer Theory» 9th ed. Springer 2017; SAE J1263 and SAE J2263.

14 min read

User guide

Carrying cargo and payload on an e-scooter: backpack vs panniers vs handlebar bag vs frame bag vs deck-mounted, max-payload engineering, weight distribution and effects on stopping distance / range / CoG / stability / tire pressure / motor thermal load

Carrying cargo on an e-scooter is not «just throw on a backpack» — it is a separate engineering discipline in which every extra 5 kg changes five parameters at once: stopping distance (through disc heating and pad fade), CoG height (the difference between a backpack at the shoulders +1.4 m above the deck and a load on the deck itself +0.2 m is up to ±0.1 m of composite-CoG shift, which changes the tip-over threshold and the wheelie limit), tire footprint and optimal pressure (ETRTO targets 15 % tire drop, ΔP ≈ 0.5 psi per +5 kg), range (every 9 kg of additional mass eats 5–10 % of range on flat ground and 10–20 % on uphill per Ride1Up and EBIKE Delight data), motor thermal load (power splits between traction force and gravity on grade, MOSFET overheating scales with the square of current). Manufacturer max-loads range from 100 kg (Segway Ninebot ES4) through 130 kg (Segway MAX G3) and 150 kg (Apollo Pro, Segway GT3) to 180 kg (Kaabo Wolf King GTR) — and that is total deck load, meaning `m_rider + m_apparat (not counted if you hold it) + m_cargo` must remain within a 15 % margin of spec due to frame fatigue, brake-component wear and folding-mechanism stress. The five most common carrier formats — backpack, panniers, handlebar bag, frame bag, deck-mounted — rate differently across five metrics (CoG-impact, steering-impact, fold-impact, capacity, accessibility). This guide is drill-oriented: composite-CoG physics, weight-redistribution formulas, a 7-step securing protocol and an 8-point pre-ride checklist. ENG-first sources: eridehero / Unagi / Levy / NAVEE manufacturer specs, XNITO load-weight-and-braking analysis, Rene Herse / SILCA tire-pressure (Frank Berto 15 % drop standard, ETRTO 20 % deflection), arXiv 1902.03661 tire-deformation paper, Ride1Up / EBIKE Delight / QuietKat range formulas, RegenCargoBikes / Academia.edu cargo-bike CoG physics, Letrigo / ADVMoto / Bike Forums cargo-securing best practices.

14 min read