BMW has 60 dummies, representing a variety of human body sizes, that gather information on how specific types of impact affect different parts of the body

BMW's safety showcase demonstrated a continued determination to get it right, writes Conor Twomey

AT THE END of two gruelling days of workshops and presentations came the highlight of BMW's safety showcase - a live crash test.

The test involves smashing a brand-new 7-Series into a flat surface at 56km/h (35mph). We're seated no more than 10 metres from the car, slightly behind the point of impact. Between us and the crash zone, there's a Perspex sheet to protect us from debris - but other than that, we're right in the thick of things. Moments before the crash, spotlights fire up and the thousand-frames-per-second cameras spring to life, followed by a quick siren burst and the whirr of electric motors pulling the 7-Series along.

It's amazing how quick 56km/h seems in a confined space, alarming how violent the impact is and I'm quite shocked at how quickly it all happens. Years of "cops on camera" shows have trained me to expect at least a half-dozen slow-motion replays, so it's something of an anti-climax for everything to be over in, literally, the blink of an eye.

We don't even get a chance to get a look at the carnage - engineers and technicians swarm, disconnecting cables, gathering debris and preparing the car for analysis later. Already, computers are logging data collected from multiple sensors inside the car and the dummies, as well as those in the wall which will help them understand which parts of the car endure the highest loads.

The lead up to the crash test comprises numerous workshops explaining various aspects of safety research at BMW.

In one section of the test facility, the forces of an impact on the interior are replicated. A high-pressure ram bashes a rig on to which BMW has bolted a stripped down 7-Series chassis. It's considerably less expensive to set up than a crash test and the same chassis can be used over and over again, replicating the effect of decelerating rapidly from 50km/h in an impact. High-speed cameras are used to see how, for example, two 17kg wooden boxes (representing luggage) fare when smashed into the rear bulkhead.

We also got a chance to meet the test dummies. I didn't expect them to be so heavy, so manoeuvrable, so diverse in terms of the data they collect. BMW uses 60 dummies priced between €100,000 and €250,000 for full-sized, 200-sensor units.

Some measure loads and deceleration, others gather impact depth and temperature data on particular points of the body. A side-impact dummy doesn't need legs or arms - what's important is knowing what the head, ribcage and internal organs are going through.

Others collect data from the spinal and neck regions, some are specifically for rear impact (with a liquid "stomach" to represent the organs) and they're all different sizes, too, representing various ages and weights.

The data collected from these dummies allows carmakers to develop new technologies such as curtain airbags, which turn a fatal side impact into a bad headache by reducing the Head Injury Criterion (HIC) level from 1,800 to 600, some way below the 1,000 widely considered to be the maximum survivable.

Indeed, it's getting to the stage where the car is no longer a factor in crash survival - it's down to the limitations of the human, both in terms of how they drive and how much abuse the body can take.

Crumple zones, airbags, seatbelt pre-tensioners and load limiters all aim to slow down the rate of acceleration, thereby preventing one of the most common causes of accident fatalities - a ruptured aorta leading to almost instant death due to massive internal bleeding.

With that in mind, BMW is working on improved active safety systems - those designed to prevent an accident in the first place - as well as communications systems that not only call an ambulance if the car is in a crash, but also direct the emergency services to the correct location and even inform them of the nature of the accident (speed of impact, G-forces endured and so on), which in turn helps paramedics to determine the best course of action for the individual concerned.

Among the active safety systems demonstrated (and available on the new 7-Series) is adaptive cruise control (which broke on our test car); blind-spot warning systems; cameras in the sides of the front bumper; accident pre-warning with brake pre-fill; lane departure warning; night vision; adaptive headlamps; speed limit recognition and rear-wheel steer, in addition to run-flat tyres and stability and traction control systems.

Some of these are quite brilliant - front cameras make pulling out of blind junctions a doddle while the rear-wheel steer gives the big 7-Series the kind of agility expected from cars half its size - while others aren't quite there yet.

The ACC system can regulate your speed but can only apply 30 per cent brake pressure, so in a real emergency you're required to jump in as soon as the car beeps at you.

The blind-spot warning systems uses an illuminated orange triangle located on the mirror to warn you if you decide to change lanes into the path of oncoming traffic, but the triangle is invisible in bright sunlight and the vibration through the steering is the same as the lane departure warning. I haven't been able to sample the night-vision, and the speed limit recognition system got it wrong at least three times during my 15-minute test drive.

Despite reservations about these new systems, BMW's commitment to safety means they will continue to improve and evolve until they not only work flawlessly but also become commonplace, like airbags, ABS, seatbelt pre-tensioner and, more recently, stability control.

© 2008 The Irish Times