Improving track safety with passive external airbags

While cars are becoming increasingly safe thanks to strengthened crash tests performed by the FIA, there is still a lot of room for improvement, both for the cars as well as for the tracks.

Looking at the current methods applied around a modern Formula One track, it is clear that massive improvements can be made to avoid injuries or even fatal crashes. Along with tarmac and gravel runoff areas, most current racing circuits are surrounded by a mixture of concrete walls and aluminum crash barriers, mostly with piled used tyres in front of them.

Taking a closer look at each of these surroundings, it is obvious that a concrete barrier is the worst among all solutions as it provides no protection in case of a high speed crash. Basically one could say concrete is only strong to protect itself, but because of its rigidity does not bend or absorb any crash energy. Such an inelastic material would result in complete destruction of the car and possible serious injuries for the driver aboard.

Another alternative used more commonly are the aluminum crash barriers. Although they are effective against low impact collisions, a current Formula One car has a far too irregular body surface for these fences to withstand a heavy impact.

Finally, most often used are now several rows of used tyres ahead of an aluminum barrier to help absorb energy. This type of fence is however not made for this purpose and could well amplify the effects of a crash due to the tyre wall's irregular surface. It has happened before that cars virtually run under the tyre wall, making it impossible for a driver to get out of his car by himself, even if uninjured.

Passive airbags

In an attempt to solve the aforementioned problems and to improve overall track safety, car designer Soussi Al haj has developed a new alternative that can be used alongside tracks as a safety barrier. The completely new system consists of passive exterior airbags. Each airbag is quite simply a passive, pre-inflated bag of air that can be used as an addition to current fencing or when applied correctly replace the current fencing completely.

These large bags can alternatively be inflated with any other kind of gas, possibly even a foam or an adequate liquid. Due to the ease of operation and the cost, (dry) air is certainly the preferred filler.

The system is precisely designed to completely absorb the momentum of a vehicle striking them in a rush on the motor racing circuits. Upon impact, the passive external airbag evacuates a quantity of air equivalent to the strength of the impact. The partially deflated bag can however remain in use as the quantity of air evacuated is at once replaced by a a pumping system which inflates the bag back to its normal volume and pressure. As such, bags can be used for a complete race, across several races or even during multiple years.

In its normal configuration, the airbag fencing can be compared to a big-sized curtain composed of many inflatable cushions attached one to another like a chain. They can be affixed to each other as well as to guarding rails behind them or possibly even on the floor, provided that the bag's structure has enough vertical rigidity. The quickest application however is without doubt replacing all current tyre walls with airbags fixed to the fencing behind it.

To be effective, the airbags should be sewn or thermoformed from various tissues in such a combination that the bag is highly resistant to high speed impacts, intrusions and fire in all weather conditions. All materials should be tested and validated, but a mixture of synthetic fibers may be a judicious choice. As such, carbon fibers or Kevlar, materials already widely in use in motor sports can be used for this purpose.

Variations to suit each situation

Depending on the appliciation of the airbags, different pressures can be applied when inflating the bags. A bag pressurized with more air can potentially absorb more energy, but the air exits will have to be sized accordingly. Each bag is therefore equipped with a considerable number of air outlets in the form of small orifice allowing a hermetic sealing when the airbag is inflated and at the same time enabling the leaving of a quantity of air contained inside the airbag(s) at the moment of the collision. These air exits are the key solution in the airbags as these allow the vehicle striking the airbags to be contained instead of bouncing back.

In order to further customize the airbags to the application, airbags can be constructed in the form of wall of many meters length or width or more to protect a racing track's borders. Another configuration could consist of one or more elements composed of many assembled portions having one or more pockets to increase its combined capacity to resist heavy impacts. Such combination could for instance be supported by a resistant plastic framework.

Whether a combination of smaller attached bags or large bags should be used will depend on the situation, studies before implementation and on full-scale tests. In essence the principle of the airbags does not exclude or mandate any construction material or shape for the bags.

These airbags are put on the circuits or roads to absorb the energy of the vehicles going out of the roads, and we may fix them, stick, fasten, weld, encase them to any fixation system according to the surface to be protected as explained before , the tissue may be a mixture based on glass fiber, synthetic fiber, or carbon fiber-based tissue or why not Kevlar fiber, but It is not excluded to increase the depth of the airbags using one or many piles of carbon with a texture of synthetic fiber or any other combination of two or more types of texture , it should has the characteristics which are the resistance to violent impacts and to unintended weather and the resistance to fire.

Apart from rigid systems, the airbags are also applicable as mobile passive airbags. These can be displaced and fixed easily in different locations and could potentially be supported on a transportable structure that can support violent crashes. This property makes this also a viable solution for temporary circuits, such as those used in the World Rally Championship.

Among the countless advantages of the passive airbags applied on racing circuits, is the transformation of circuits and roads into a more secure place. The system can be easily used to replace inferior and currently widely used systems for track safety. By their property to efficiently absorb energy through controlled deflation of the airbags, these airbags become an unhoped-for protection that perfectly absorbs the energy of the impact and does not transmit it to vehicles striking it.

Another advantage is the displaying surface gained thanks to these external airbags along the circuits or roads, wherever they are applied. This functional surface can be advantageously utilized by advertisers.

In the end, there is currently real potential for this product on circuits around the globe. The external airbags are easy to develop and put in the market as the required technology is already available for further research and implementation.

Note that this technology is new and patented with PCT by Mr. Souissi Al Haj. He is looking for a business partner to develop this invention and put it on the market. You can contact him through his user profile or by direct email to dubai2008@hotmail.fr or souissi12000@yahoo.fr .