Losing concentration

Losing concentration while driving can have serious repercussions for drivers and other road users. But the designers of the new Lexus LS 600h have a solution to the problem - they've developed a system that keeps an eye on the driver and his or her concentration levels.

The driver monitoring system forms part of a Pre-Crash Safety (PCS) system which brings together a series of features that can recognise a potentially dangerous situation, help the driver take avoiding action and reduce the risk of a collision happening. If there is an impact, they also work to help minimise the consequences.

The system uses an algorithm to map the position of the driver’s facial features and monitors movement of the driver’s head. A CCD camera is mounted on top of the steering column with six built-in near-infrared LED’s which allow the system to work day and night.

When the vehicle is started up, the system automatically plots the position of the driver’s facial features – eyes, nose and mouth – and measures the width and centre line of the face. If the driver’s head is turned away from the road at an angle of more than 15 degrees when the vehicle is moving and an obstacle is detected ahead, the system automatically activates the Pre-Crash warning buzzer and briefly applies the brakes to warn of the danger.

If this still fails to prompt action from the driver, the PCS engages emergency braking preparation and pre-tensioning of the front seatbelts.

Before being put into production, the system was tested with more than 100 drivers, covering a total of more than 60,000 miles. As long as the driver’s face is in the clear sight-line of the camera, it will function accurately, regardless of the driver’s seat position, facial characteristics, or if sunglasses are being worn.

As well as scanning the driver’s face and the road ahead, the Lexus LS also sports a system to look at what's going on in the rear of the vehicle. 

In this system, a rear-mounted miniature camera constantly monitors the area around the back of the car. If it detects an imminent collision, the front seat headrests will automatically move up and forwards to cushion the occupants’ heads and help prevent whiplash injury. The system operates whether the car is moving or stationary.
 
If a collision is calculated to be unavoidable, the system activates the front seat headrests. These then move up to 60mm forwards and 35mm upwards to cushion the head in anticipation of an impact, reducing the risk of whiplash injury. The headrests are fitted with a sensor that measures the distance between the passenger’s head and the headrest itself, so there is no risk of the emergency adjustment itself causing substantial contact. The system does not operate if the seat is unoccupied.

The systems will be fitted as standard on the LS 600h and LS 600h L (long wheel base) as well as the LS 460, launched earlier this year.