“ARTS is the world’s first occupant-sensing system, to give maximum control over the deployment of airbags in any kind of impact”

To optimise protection, ARTS senses the severity of a crash, the position of the driver and the usage of the seatbelts to provide tailored protection. The occupancy-sensing system uses ultrasonic technology combined with a seat weight sensor to also detect the presence, position and size of a front seat passenger. ARTS uses this information to determine the airbag energy levels most appropriate to the individual occupants during a frontal crash and to control whether the two-stage airbags are deployed at all, or inflated fully or only partially.

If the front airbags are deployed, they will be inflated fully or partially depending on the severity of the impact and the data from ultrasonic occupant sensing. In a severe impact, the airbags will be deployed with full force. In other circumstances, for example a low-speed collision and with a small front-seat occupant in the car, the airbag will not inflate with full force because it does not need to, and because doing so could actually be more hazardous. That means in every case the airbags in Jaguars provide the maximum level of appropriate protection, but not so much “protection” as may be harmful.

2005 Jaguar S-Type

The system introduced the world’s first ultrasonic occupant-sensing system, to give maximum control over the deployment of airbags in any kind of impact. Ultrasonic occupant sensing is combined with a series of other sensors that assess a passenger’s weight, the position of the driver in relation to the steering wheel, whether or not seatbelts are being worn and, in the event of a crash, whether or not the impact is severe enough to need the airbags.

By being sophisticated enough to tailor airbag response to the needs of each front-seat occupant and the severity of any impact, ARTS greatly reduces the risk of injury caused by unnecessary airbag deployment and is particularly beneficial for smaller front-seat occupants, who are more vulnerable to airbag-related injury. It also avoids the cost of airbag replacement when a deployment wasn’t needed – either because the seat was unoccupied or because the impact didn’t require it.

ARTS also features an energy-absorbing seating system, incorporating an anti-whiplash mechanism in the front-seat back rests, and pyrotechnic pretensioners for all seatbelts. Dynamic stability control is another standard-fit active safety system on the new S-Type launched this year. It enhances safety at the limits of grip and roadholding, which is especially valuable when road conditions are poor. If it recognises the onset of instability – either understeer or oversteer – it takes measures to counteract it. That might be by reducing engine torque or selectively applying gentle braking to one or more wheels, or a combination of both. The system also intervenes to prevent wheelspin in low grip conditions, automatically reducing power and, if necessary, braking individual wheels.

“Faster-acting than any driver, Jaguar’s emergency brake assist can dramatically cut raking distances, with obvious safety benefits”

Front park assist in addition to reverse park assist that is already available across the range is a sophisticated speed-sensitive system which helps the driver to avoid unseen obstacles such as hidden kerbs or low bollards, and it switches off automatically at speeds above 9mph (15km/h). It is also less sensitive than the rear system, so that it does not, for instance, pick up cars ahead in slow-moving traffic. A radar sensor mounted under the bumper cover is used in addition to the new S-Type’s adaptive cruise control and forward alert. Conventional cruise control is now standard across the range, with adaptive cruise control optional. Adaptive cruise, like normal cruise control, allows the driver to set and maintain a cruising speed, but it is also able to detect slower-moving vehicles ahead and will slow the new S-Type below the set speed as necessary. When the traffic ahead speeds up, adaptive cruise will return to the driver’s chosen speed.

The new Jaguar X-Type Estate

Forward alert uses the same sensors to detect obstacles ahead of the car even when it is not in adaptive cruise mode, and alerts the driver with an audible signal and a dashboard light. The driver can adjust its sensitivity to cover a preferred range and can switch it on or off as desired. As with front park assist and adaptive cruise control, it is available across the full model range.

At the opposite end of the Jaguar model spectrum is the new XJ long wheelbase which will go on sale in the UK from the autumn. The luxury sporting flagship shares all the advantages of advanced aluminium construction, including light weight, significantly improved body strength – it is constructed using an extended version of the innovative aluminium monocoque introduced last year when the standard wheelbase model was launched with the additional body length incorporated behind the B-pillars – and comprehensive safety features.

Jaguar XJ8 airbags

In the spring, Jaguar launched the revised XK with drivers having the option of increasing the specification of their car by choosing new Premium and Technology packs. These optional packs greatly increase specification over a standard car and include such extras as reverse park control. Meanwhile, a new automatic speed limiter is added to the wide range of electronic systems already standard across the XK range to further enhance the driver’s ease. Revisions to the XK since 2001 have seen all models fitted with ARTS, emergency brake assist and dynamic stability and adaptive cruise control become an optional extra.