Inflatable 'airbag' for cyclists

Two Swedish students have designed a revolutionary airbag for cyclists that remains completely hidden away when it is not needed - but springs into action in the event of an accident.
The inflatable device is stored inside a durable collar that is worn by the cyclist at all times. Abnormal motion triggers the mechanism which inflates a hood-shaped helmet in a split second (0.1 second, to be precise) thrusting it up out of the collar and over the wearer's head.
By the time the cyclist hits the floor, their head is entirely protected, surrounded by the asphalt-proof nylon hood. 
The airbag provides shock absorption and pressure for several seconds, meaning it can withstand several impacts to the head in the same accident before slowly deflating.
Anna Haupt and Terese Alstin, the designers behind the 'Hovding' helmet, say they approached the safety gear industry from an entirely new angle.
They dispatched of the traditional hard shell altogether, creating a helmet that is not only invisible for the majority of the time, but is worn in a device that becomes a fashion accessory - and provides more protection than a standard helmet.

The two conceived the idea when they were working on their design thesis at Lundig University. 
The Swedish government had just introduced a law making cycle helmets compulsory for under-15s, and were discussing the possibility of extending the law to adults.
Such nanny-state action was seen as a threat by the Swedish public - so Haupt and Alstin set about finding a way to make wearing helmets an enticing prospect, instead of a sort of punishment, their goal to make something so stylish that people would voluntarily protect themselves instead of having to be forced to do so by law.
With the help of the Swedish Stunt Group and the Swedish National Road and Transport Research Institute, the two had hundreds of bicycle accidents recreated to ascertain exactly when the sensors should deploy the airbag.
The airbag is deployed by sensors – accelerometers and gyros – that pick up on cyclist's abnormal movements in the event of an accident. The sensors then send a signal to the gas inflator to inflate the airbag.

Inflation happens thanks to a small cold gas inflator concealed in a collar on the cyclist's back that uses helium to speed-inflate the device.
Once the bags have been deployed, they can be sent back to the company for recycling, and customers will receive a discount on a new Hovding product.
The helmets are completely legal, and have been cleared by the Swedish government as regulation safety gear - but crucially for the youngsters who Hovding Sverige hope will wear them, they look good too.
Indeed, the firm unveiled the device in a fashion show in Stockholm last year, proving that the unobtrusive garment can be styled dozens of different ways, with faux fur, leather and spotty silk being just a handful of the coverings available for the collar.
In the fashion show's finale, the firm sent out a bride wearing a white silk collar with the inflatable helmet engaged, acting as a sort of veil - the perfect marriage of fashion and function.