Analysis of a crash

07/06/2016
NEWS STORY

For most of us, probably including the man himself, Fernando Alonso's horrific crash during the season opening Australian Grand Prix is a distant memory.

Indeed, if you watched the excellent Life at the Limit on ITV4 at the weekend you'll realise that we now regularly see drivers dusting themselves off and walking aways from accidents that would have been totally unsurvivable not the long ago.

Alonso's Melbourne crash however was unique, in the sense that for the first time every single new safety measure has been coordinated to allow a full forensic study of what happened.

A high-speed camera directed at the driver has been installed on every car from the start of the season and in conjunction with a tiny accelerometer in the driver's earpiece measures the forces on his head. This, in tandem with the Accident Data Recorder, the F1 equivalent of the 'black box', measures all the external forces.

"Combined with the multiple camera angles from the cameras around the track, safety researchers have more information than ever before to determine what exactly happens at every millisecond of a crash," reveals the FIA in its Auto magazine. "This is essential for deciding on future areas of safety development and research."

The Spaniard crashed into the back of Gutierrez' Haas at the end of the DRS zone between Turns 2 and 3 in Melbourne. At the time he was travelling at 313kph (194 mph) as he began his overtaking manoeuvre and had slowed marginally to 305kph (189 mph) at the point of impact, when his front-right wheel made contact with the rear-left wheel of Gutierrez's car.

Following the initial impact, Alonso's front-right suspension was destroyed, and the car veered left towards the outside wall. The collision was made with the front left corner of the car, resulting in a peak lateral deceleration of 45G, with high acceleration levels also recorded by the ear accelerometers, demonstrating the forces on the driver's head.

The High-Speed Camera, which took video frames of the driver every one hundredth of a second, showed that Alonso's helmet made contact with the left inside face of the headrest twice during the impact, corresponding with two peaks seen on the ear accelerometer data.

The car rebounded and proceeded to slide along the circuit towards the gravel trap. With front-left, front-right and rear-left suspensions destroyed, the car was heavily leaning laterally on its left side as it travelled over the grass. This left side dug into the gravel, which rolled the car and propelled it into the air, recording a lateral deceleration of 46G.

The car travelled in the air, rotating approximately 540 degrees (1.5 times) and was airborne for 0.9 seconds. On landing it made its initial contact with the ground on its rear impact absorbing structure, experiencing a peak longitudinal acceleration of 20G.

The car then rotated about its rear before falling and eventually coming to a stop on the left side of its engine cover, just before the tyre barrier.

Yet Alonso walked away.

A report into the accident by the Global Institute for Motor Sport Safety, the research partner of the FIA Institute, concluded: "From an initial 305kph impact, the car of Alonso was able to manage three high-G decelerations and an airborne phase without major injury to the driver, primarily due to a range of safety systems on the car performing well for their designed purpose."

Unbelievably, much of this data was delivered to medics and researchers at the track in real time.

"We receive the data in real time as the car is running, so if it crashes the ADR is able to send us a signal to give us a rough idea of the magnitude of the accident," Laurent Mekies, Global Institute's General Manager Research, told Auto.

"We have that in the same timeline as any other parameters so we can put that on the same graph with the car speed, where the driver braked, with anything that is recorded by the car and this allows us quite a reasonable understanding of the dynamic of the car from the loss of control to the actual crash and impact."

The accelerometer is housed in the driver's earpiece with a wire running straight into the Electronic Control Unit (ECU) of the car, alongside the cable from the ADR.

"That's the beauty of the system," says Mekies. "You gain all that info in a non-invasive way for the driver because we don't add extra connections; we just use what is already available there and add our own stuff into it. That was very much the driving concept in the way we are trying to implement this data system."

Similarly, the high-speed camera is hidden in the cockpit surround behind the steering wheel. However, footage from this camera cannot be delivered in real time because there is a huge amount of data from recording at 400 frames per second. To prevent any loss, this data is recorded twice on the car - on the camera itself and also transmitted to the ECU.

The footage has already proved invaluable for safety researchers. Mekies says: "What we want to understand is the exact dynamic of the head, neck and shoulders in a high-G crash and how they interact with the other parts of the cockpit environment - the padding, the HANS, belts and anything else that can be in the space of the driver. This camera allows us to better understand the exact forces on the head to a given displacement, the elongation of the neck, how it engages with the headrests, how the headrests perform and what we need to do to produce the next generation cockpit environment."

For any major accident, all of the information collected from a crash is studied by the FIA and sent to Global Institute researchers for further analysis.

"One of the primary functions of the Global Institute is to be a crash investigation body," says Mekies. "This means that on one side we do the crash investigations and on the other side we actually do the research into mitigating the consequences of crashes that we have analysed. So this gives us a full 360-degree approach.

"It's also very important that everybody fully embraces what we are trying to achieve and why we need all these sensors on the cars. [F1 Race Director] Charlie Whiting is giving us invaluable support by keeping the communication flowing with the teams and the drivers, and is always pushing us to go and target the next step."

But this work is not just limited to F1. The FIA recently launched a World Accident Database for every championship to insert data from major accidents. The Global Institute analyses that data and feeds back recommendations to the corresponding series.

Safety researchers have more data than ever before but there is more to come. Despite the detail with which that they can currently analyse an accident, there is always more that can be added to the picture to give a clearer view.

Tools of the Analysis

In-ear Accelerometers

These tiny accelerometers have been housed in silicon gel (above) and designed to sit in a driver's ear canal to precisely measure the accelerations of a driver's head in the event of a crash.

Introduced into Formula One in 2014, they work in combination with the Accident Data Recorders that measure the forces acting on the car and provide hugely important information.

After a few years of research, which included getting the accelerometer to measure the forces that can peak at 400G, the devices were trialled and then introduced into the top level of motor sport.

High-Speed Cameras

This cockpit-mounted camera, which was introduced to F1 in 2016, rapidly films the driver at up to 400 frames per second. The data captured by the camera provides accurate information of what happens to a driver in the event of a crash, which may have been missed by previous technology, and can help inform medical officials of any injuries.

The research team at the Global Institute worked together with Charlie Whiting's FIA F1 team of engineers and automotive engineering company Magneti Marelli to create a prototype system that would record images in real time onto the memory of the car's black box device, which was specifically designed to have the capacity and processing power to receive and record the video data.

The camera that has been developed is 12mm wide, 25mm tall and around 80mm in length, roughly half the size of a smart phone. These specifications are designed so the camera can be integrated seamlessly into the cockpit of a single-seater car (above).

Accident Data Recorders

Accident Data Recorders (ADRs) capture data about the performance of a car during a crash, which can be downloaded and interpreted by researchers to study how the safety devices reacted during an impact.

They help researchers understand how the driver's safety equipment is performing and allows them to more fully understand the limits concerning drivers' tolerance to injury. With ADRs working in conjunction with devices like the high-speed camera and the accelerometer, a bigger and fuller dataset can be collected and a better picture of an accident emerges. All of that data is then fed into the World Accident Database.

Although Formula One, the World Rally Championship, and other high-profile series have already been using ADRs for some time, for many lower-level series the price of the system had prohibited its widespread use. But following research conducted by the FIA Institute that successfully reduced costs, from the beginning of the 2015 season, ADRs became mandatory for all FIA Formula 4 championships around the world.

"I don't like to call it a complete picture because I think we have added one step and there will be other steps after that," says Mekies. "It's an exercise that never stops, but it is certainly a very significant step."

The next step is biometrics - gathering data from drivers such as heart rate, body heat and even sweat levels.

"I hope that we will be able to put something on a driver before the end of the season, at least in a test. Biometric data will help us to assess the driver's conditions before, at the time of the crash and after the crash, as far as the rescue operations are concerned."

There are also plans to have more cameras pointing at the drivers in future. F1 is bringing in a cockpit protection system and this will offer further opportunities for camera placement above the driver. There is no end to the usefulness that this data would bring to drivers.

As Mekies puts it: "You could imagine a million things tomorrow - you could imagine us trying to estimate the loads on the actual upper body of the drivers through the safety belts, for instance.

It is something that will never stop as much as safety research will never stop and we will continue to push the boundaries to gain
a deeper understanding."

Again, watching Life at the Limit at the weekend, and the many heroes we have lost, this is a move in the right direction.

Picture credit: John Morris (MPix)

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Published: 07/06/2016
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