Seatbelts to restrain passengers during an accident and save them from more serious injuries due to smashing against the dashboard or even crashing through the windscreen began appearing in the 1960s. Volvo lays claim to having been the first carmaker to encourage its customers to use these safety devices – initially just across the waist – by providing anchorage points initially and then including the seatbelts as standard.
Over the years, seatbelt mechanisms didn’t change significantly and the only major innovation has been the pyrotechnic pre-tensioner which was developed to enable airbags to work more effectively. By tightening the reel a split second before the airbag fully inflates, the occupant is not flung forward so much that he or she is being propelled forward against an airbag inflating at 200 km/h.
But in spite of minimal evolution, the seatbelt is still regarded as the primary restraint system and this is always emphasised because the airbags are designated as “Supplementary Restraint Systems” which is what the ‘SRS’ you see on airbag-equipped vehicles stands for.
Soon, a major advancement in seatbelt design will become available in cars and it’s technology that was originally designed for aircraft use. Known as the ‘SmartBelt’, the system works with existing vehicle airbags. During a significant crash, the system rapidly inflates a bladder that runs the length of the belt from the buckle to the point where it enters the upper part of the seat or pillar.
The ‘Smartbelt’ is a patented design by BFGoodrich which you may know as a tyre company. But the original BFGoodrich which was a tyremaker actually exited the automotive tyre industry back in 1986 after selling its tyre business to Michelin (which still manufactures and markets tyres with the BFGoodrich label). Today’s BFGoodrich is a leader in aerospace systems and services, performance materials and engineered industrial products
The company says that its system will be available to the public within two years. In initial applications, ‘SmartBelt’ systems will provide added protection in cars for rear passengers. BFGoodrich expects the product to become a standard feature in cars and even planes, trains and school buses within a few years.
“The inflatable seatbelt is a giant step forward for passenger safety because it provides airbag-like qualities while deploying away from the wearer and then cradling him or her into the impact,” said Mike Vecchio, Safety Consultant for BFGoodrich.
The ‘SmartBelt’ actually works in concert with the airbag and can create additional protection for smaller occupants and especially children – which has been a major issue for manufacturers. The ‘SmartBelt’ inflates within the first 10 milliseconds of a crash, and the airbag deploys after 25-30 milliseconds so the wearer becomes “pre-positioned” by the SmartBelt to more safely accept the enormous force of the airbag. Therefore the airbag’s ability to protect is optimized.
In side-impact crashes too, the ‘SmartBelt’ system is claimed to out-perform airbags and conventional seatbelts. Tests have conclusively shown that its its usage would result in a driver or passenger sustaining considerably less head injury than if they were using traditional airbag/seatbelt combinations. Additionally, the ‘SmartBelt’ is said to offer superior rollover protection, even in convertibles.
The ‘Smartbelt’ addresses some of the drawbacks of conventional seatbelts which can cause pain and, in some cases, even severe injury. That’s because the force between a body and a seatbelt can be tremendous – up to 55g (the factor which body weight is increased by). The ‘Smartbelt’ is said to provide two benefits to reduce this effect, firstly by the additional cushion for the occupant and secondly, though force distribution over a wider area on the body since the belt’s bladder expands to a full 150 mm width.
Most likely, this next-generation seatbelt will first appear in vehicles made by North American carmakers and then other manufacturers around the world will slowly adopt them.