Driver assistance systems

Assistance or automation: the difference

Assistance systems support you: they warn or intervene briefly. Control remains entirely in your hands.

Automation goes further: the vehicle takes over the driving in defined situations. But even then you remain responsible for as long as you must be able to take back control.

The most important systems

• ABS: prevents the wheels from locking – the vehicle stays steerable under braking. Limit: it does not shorten the braking distance on ice.
• ESP: brakes individual wheels to stabilise the vehicle. Limit: it cannot recover a plainly excessive entry speed.
• Automatic emergency braking: brakes by itself when a collision threatens. Limit: narrow objects such as cyclists are not always detected.
• Adaptive cruise control: maintains speed and gap. Limit: it reacts late to vehicles cutting across.
• Lane keeping assist: corrects the line. Limit: faded markings or roadworks confuse it.
• Blind spot warning: signals vehicles in the area you cannot see. Limit: it does not replace the shoulder check.

The limits of every system

Sensors: cameras and radar are limited by snow, heavy rain, fog, backlight or dirt. A sensor covered in mud simply stops working.

Physics: no system can overcome the laws of grip. If the grip is not there, it is not there – with or without electronics.

Switching systems on and off

Many systems can be switched off; some switch themselves back on when the engine is started.

The sensible approach is to leave switched on those that work in the background – ABS, ESP, emergency braking – and to use deliberately those that intervene in the driving, such as cruise control or lane keeping.

Remember: however many systems are on board, you are driving and you are answerable. An assistant is a safety net, not a pilot.