La différence entre sécurité active (active safety) et sécurité passive (passive safety) est que les composants de la premières ont vocation à éviter les accidents. Les composants de la sécurité passive quant à eux cherchent à réduire les conséquences et dommages d’un accident.
Le premier levier “actif” de sécurité est d’avoir un véhicule pilotable facilement et prévisible, c’est à dire avec des liaisons au sol bien conçues, des freins efficaces et prévisibles et une motorisation fonctionnelle. Le véhicule doit être ressenti par le conducteur comme un ensemble homogène.
Le second levier est d’offrir au conducteur un environnement de conduite non agressif. Il faut notamment veiller à limiter le bruit (moteur, pneu, aérodynamique), les vibrations (moteur, transmission, suspension, aérodynamique), et l’impact des conditions climatiques (température, humidité, vent et pression).
Enfin, dans les derniers éléments de base à la sécurité active, on va retrouver:
Maintenant, les véhicules proposent aujourd’hui des fonctions plus complexes permettant d’optimiser le contrôle de son véhicule même en situations précaires. On retrouve notamment:
Electronic Stability Control (ESC)
Lane Guard Warning System (LGWS)
Advanced Electronic Braking System (AEBS)
The General Safety Regulation (GSR) is the European Union framework that sets out the safety equipment new motor vehicles must carry. Its second phase, GSR-II, applying to new heavy vehicle types from 2024, mandates a defined suite of active-safety systems intended to prevent collisions or reduce their severity. The principal requirements for heavy goods vehicles include autonomous emergency braking (AEBS), which detects an impending collision and brakes automatically and which must now also recognise vulnerable road users such as pedestrians and cyclists; intelligent speed assistance (ISA), which informs the driver of the prevailing speed limit and of any overspeed; driver drowsiness and attention warning; blind-spot and turn-assist systems that warn of, and may automatically brake for, cyclists and pedestrians alongside the vehicle during a turn; an emergency stop signal that flashes the brake or hazard lights under heavy braking to alert following traffic; reversing detection to identify people or obstacles behind the vehicle; and tyre-pressure monitoring. This page gives only an overview of these mandated systems; the braking mechanism is described on the Brakes page, and the sensors and software behind the driver-assistance functions are covered on the Electronic systems page.
The value of these requirements is uneven, and an honest assessment distinguishes the genuinely useful from the immature. Tyre-pressure monitoring, for example, delivers a clear safety and fuel benefit at little cost. By contrast, the sign-reading element of intelligent speed assistance is at present unreliable, since camera recognition of speed-limit signs is readily defeated by temporary, hidden or ambiguous signage and can warn incorrectly. A continuing policy debate concerns how far such functions should evolve, including the prospect of future binding speed limitation that would actively cap a vehicle's speed rather than merely warn the driver; the current generation of systems is advisory, and their reliability is one reason caution is urged before mandatory intervention.
Beyond braking-based stability control, active steering systems contribute to keeping a heavy vehicle on its intended path. Understeer-correcting functions, marketed for instance as Smart Steering, apply small automatic steering inputs to counter understeer and assist lane-keeping, improving directional stability in adverse conditions. The steering hardware and its integration with the vehicle's dynamics are discussed on the Chassis page.