Safety

Safety  - Overview - Volvo XC70

Safety is the key quality of any Volvo. Ever since the first Volvo was built in 1927, the overriding priority has been to develop cars that help prevent accidents and, if the accident does happen, to offer maximum protection. 'Cars are driven by people. Therefore the guiding principle behind everything at Volvo is, and must remain, safety,' declared co-founders Assar Gabrielsson and Gustaf Larson.

'When we developed the all-new Volvo XC70, our goal - just as for the all-new V70 - was that it should be the safest car in the segment,' says Hans Nyth, director of Volvo Cars Safety Centre. 'The XC70 model shares the same sophisticated network of interacting safety systems as the Volvo S80. The patented body structure absorbs energy in a highly efficient way. And the interior safety system includes the latest generation of side airbags and whiplash protection. What is more, we are introducing a world innovation in the field of child safety.'

'The best way to stay safe is to avoid accidents'

The Volvo XC70 has the most comprehensive and sophisticated array of safety protection devices in its class, and its suite of accident avoidance and stability devices is no less impressive.

These include numerous advanced braking functions (see 'Driving Dynamics: Steering, Brakes and Transmission'), Volvo's DSTC (Dynamic Stability and Traction Control - see 'Driving Dynamics: Chassis') and Collision Warning with Auto Brake (see 'Driving Dynamics: Steering, Brakes and Transmission') - Volvo's clever new technology that reduces the risk of rear-end accidents.

Active bending headlamps

Good headlamps are essential for safe night driving, especially in a car that is designed to go to out-of-the-way locations, miles from any public lighting. The standard halogen headlamps give an excellent light spread on low or high beam and are automatically height-adjusted to avoid dazzling oncoming cars, irrespective of load.

For even better illumination, the Volvo XC70 can be equipped with Active bending headlamps - swivelling headlamps that follow the sweeps and bends of the road. The headlamps can be swivelled up to 15 degrees in either direction, totalling 30 degrees, and can light up a longer stretch of road as it twists and turns. In order to save wear and tear on the system, it is automatically deactivated in daylight.

Like the standard halogen headlamps, the Active bending headlamps are automatically adjusted depending on how heavily the car is loaded and also on whether the car is accelerating or braking. So the headlamps always point at optimal 'level' height.

The headlamps are cleaned using an electromagnetic, high-pressure system that washes one headlamp at a time - another ingenious Volvo safety feature - so as to always provide the best possible illumination under all conditions.

Advanced driver information systems boost safety

The Volvo XC70 can be equipped with BLIS (Blind Spot Information System) and LDW (Lane departure warning) with DAC (Driver Alert Control). Using cameras integrated into the door mirrors, BLIS registers whether another vehicle is in the blind spot offset to the rear of the car. If there is a vehicle there, a lamp lights up at the relevant mirror to alert the driver.

Rather than monitoring human behaviour (which varies from one person to another) DAC monitors the progress of the car on the road. Monitoring driving behaviour is more reliable as it assesses the impact that fatigue or distraction has on the car's movements and assesses whether it's being driven in a controlled, consistent manner. This system consists of a camera located between the windscreen and the interior rear view mirror, a number of sensors and a control unit. The camera measures the distance between the car and the road lane markings, while the sensors register the car's movements. This information is sent to the control unit which then calculates whether the driver is at risk of loosing control of the car. If the risk is assessed as high, the driver is alerted via an audible signal, while a text message and coffee cup symbol appear in the cars information display to urge the driver to take a break. The driver has the opportunity to access driving information throughout a journey, the starting point is five bars and the less consistent the driving, the fewer bars remain.

Both the Driver Alert Control and Lane Departure Warning are activated when the car reaches 40mph and they will stay active as long as the speed exceeds 37mph. The availability of these systems depends on the number and quality of visible road markings. The lane markings must be clearly visible and poor light, fog, snow and extreme weather conditions can make the system unavailable.

IDIS (Intelligent Driver Information System) is standard on all Volvo XC70 models. IDIS is an electronic information system that helps prevent the driver from becoming distracted by irrelevant information in busy situations. By continuously monitoring certain functions in the car, such as brake application and movements of the steering wheel, accelerator pedal and turn indicators, IDIS can assess the complexity of the driving situation. The information is processed and at a certain level of complexity, any information that is not essential to safety is delayed, for instance incoming phone calls or SMS text messages.

ACC (Adaptive Cruise Control) with Distance Alert and Collision Warning with Auto Brake

To help the driver maintain a safe distance from the car in front, Volvo has developed Adaptive Cruise Control or ACC. It uses a radar sensor to measure continuously the distance to the vehicles in front and automatically adapts the speed of the car to help ensure the distance is not too short. This technology also forms the basis of several of Volvo's advanced driving and support systems, including Collision Warning with Auto Brake.

The driver activates the cruise control, setting the desired maximum speed at between 18 and 125mph, and chooses the minimum time interval to the cars in front. There are five different time intervals to choose from.

Distance Alert is another feature included in this option. The system helps the driver maintain a safe distance to the vehicle in front even when Adaptive Cruise Control is not in use. Activated via a button on the centre console, the driver can choose between five settings, similar to that of the ACC. If the time gap to the car in front gets shorter than the selected speed, the driver gets visual information in the head-up display on the lower section of the windscreen.

ACC with Distance Alert forms an option along with Collision Warning with Auto Brake.

Child safety improved with two-stage booster cushion

Volvo has also been a pioneer in child safety - an area of car design that is frequently overlooked. A world first for the Volvo V70 and XC70 is a height-adjustable booster cushion. Integrated into the rear seat, it can be set at two heights, allowing children of different sizes to see out of the car while also getting optimal seatbelt support. The lower setting is intended for children between 115 and 140cm in height and weighing between 22kg and 36kg. The upper setting is designed for children measuring 95-120cm and weighing between 15kg and 25kg. The integrated child booster cushions can be used on both outer rear seats.

The seats are specially designed so that the seatbelt geometry is optimum irrespective of the child's height. The safety belts also have specially adjusted force limiters so they restrain the child with just the right amount of tensioning force in a collision.

'It's a sad fact that the least well protected occupants in many cars are children,' says XC70 project director Tomas Ahlborg. 'This is because the child seats don't fit them properly, the seat is not properly secured or the belt does not fit them correctly. This new Volvo innovation optimises safety for children who have grown out of rear-facing baby chairs but who are too small to sit in a normal adult seat.'

SIPS side impact protection offers even greater safety

Volvo has also further developed its SIPS (side impact protection system) thanks to a stronger side body structure. The body's entire side structure is both stronger and lighter thanks to a well balanced combination of high-tensile steel of different grades (High Strength Steel, Extra High Strength Steel and the extremely strong Ultra High Strength Steel). The various components and grades of steel interact to reduce penetration into the passenger compartment.

The inflatable roof curtains in the Volvo XC70 have been extended by 60mm, offering greater head protection for children and adults alike.

The Volvo XC70 also gets a new type of side airbag. These new side impact airbags have two separate chambers - one for the hip section and one for the chest. The hips can withstand greater force than the chest, so the lower chamber inflates with up to five times more pressure than the upper section. The side impact airbags interact with the inflatable curtains and the car's network of safety beams to provide the most effective possible protection.

Crumple zones made using different grades of steel

The patented front body structure in the Volvo XC70 is divided into zones, each of which has a different task during the crash sequence. The outer zones are responsible for most of the deformation. The closer the collision forces get to the passenger compartment, the less the material deforms. In order to give each zone the right properties, different grades of steel are used in different structures. In all, there are four different grades. Apart from regular body steel, three different grades of high-tensile steel are used: High Strength Steel, Extra High Strength Steel and Ultra High Strength Steel.

These crumple zones are:

Zone for deformation at low speeds: The front bumper is attached to a cross-member made of aluminium. The attachment points at the body's longitudinal beams are designed as collapsible 'crash boxes'. They absorb low-speed collision forces without damaging the rest of the body's beam structure.
Zone for deformation at high speeds: The straight sections of the longitudinal beams are made of High Strength Steel, a very tough grade of steel optimised for high energy absorption. This zone accounts for most of the deformation.
Back-up zone: The beam section that curves out towards the A-posts serves as a barrier protecting the passenger compartment and also as a back-up to reduce deformation. Its shape also helps minimise the risk of the front wheel penetrating the passenger compartment. Instead, the wheel helps absorb the collision forces. This section is very rigid and is made of Extra High Strength Steel.
Three-point attachment: A rigid cross-member links the two A-posts and the lower side-members so that they form a particularly sturdy three-point attachment on each side. This design is particularly effective at protecting the passenger compartment in a severe impact.

Compact transverse engines improve safety

Like all other models in the Volvo range, the Volvo XC70 has a transverse driveline. A transverse installation gives the engine more space inside the engine compartment to allow the crumple zones and other safety systems to work more effectively. It also reduces the risk of the engine penetrating the passenger compartment in a frontal impact.

Second-generation WHIPS system

WHIPS (Whiplash Protection System) reduces the risk of neck injuries in a rear-end collision. The front seat backrest accompanies the passenger's initial body movement and dampens the incoming force rather like one's hand does when catching a ball.

The Volvo XC70 features the same generation of WHIPS mechanism as was launched on the S80 model and the V70. This generation was further developed to ensure that the damping motion is gentle and to provide good contact between the head and head restraint throughout the impact sequence.

Protection for pedestrians and cyclists

The new, rounder front end of the all-new Volvo XC70 has a large, energy-absorbing soft structure in front of the bumper that helps reduce leg injuries to other road users in the event of a crash. The spoiler's lower edge has also been reinforced and moved forward, almost on a level with the bumper. The area of contact on a pedestrian's or cyclist's leg should be distributed across a larger area, reducing their risk of injury.

The bonnet is raised on impact to help cushion any blow and its underside has a honeycomb structure that absorbs crash energy and reduces injury.

Protection for other motorists

With its high ground clearance, the Volvo XC70 has relatively high bumpers. This creates a greater potential risk of damage to an oncoming 'normal' passenger car. To reduce the risk of injury in a collision, the front suspension subframe in the Volvo XC70 is supplemented by a lower cross-member, positioned at the height of a conventional car's bumper. This lower beam is integrated into the Volvo XC70's structure and is neatly concealed behind the spoiler. In a collision, the lower cross-member should strike the oncoming car's protective structure, activating its crumple zone as intended so the occupants can be given the maximum level of protection.

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