BMW's GINA concept car features a flexible skin instead of solid body panels

What if the exterior of a car wasn't made of heavy, rigid metal? What if it was made from flexible fabric stretched over a moveable structural subframe? BMW's GINA concept explores the design possibilities opened up when a car's exterior is completely flexible - from variable lines to hingeless doors to eyelid headlights - in one of the most fascinating design studies we've seen in years.

One design element of cars that has been largely taken for granted is the rigid outer shell - but designers at BMW are asking the question: is there a flexible alternative? Metal car exteriors are heavy and expensive. They dent easily, are costly to paint - and in serious accidents, they sometimes twist into a metal cage, meaning emergency crews have to call on huge hydraulic cutters to extract injured drivers.

From a design point of view, a solid exterior means that a car's design has to stay static, and features that need to be exposed have to generally remain revealed or behind doors or hatches. A flexible fabric covering, on the other hand, allows the exterior shape of the car to be quite dynamic, bending, extending and moving to fit the contours of the moving substructure beneath it.

The GINA (Geometry and Functions in 'N' Adaptations) Light Visionary concept is BMW's future-focused design study on the possibilities offered by flexible coverings. Based on a 2-seater roadster platform, GINA's revolutionary exterior has allowed its designers to do away with the traditional body panel approach, concentrating on visual and structural lines rather than full body pieces. The stretched fabric follows the outlying lines and forms visually pleasing curves between them.

GINA's doors don't have any external hinges - instead, the internal subframe tilts upward and the car's 'skin' simply flexes as the door opens. Its headlights are completely covered when they're not in use, and when they're switched on, the curve of the bonnet changes to accept higher side ridges as GINA's 'eyes' open up. The rear spoiler moves beneath the skin, creating extra downforce at higher speeds while maintaining slippery aerodynamics. The indicators and tail-lights are hidden, and shine through the skin, which is permeable to light, but not transparent, and the intake grille can adjust its size if more or less air is needed.

Opening the hood to work on the engine is like performing surgery - the fabric is opened down the middle of the bonnet and the sides are pulled apart to allow access. The safety aspect of the car is entirely handled by the structural frame beneath the skin.

The effect from a design perspective is quite striking - and even if the GINA concept is mainly a styling exercise at the moment, it opens up some very cool possibilities down the track. Multistructural cars could be built on a platform that, at its core, simply encompasses a rolling chassis, engine and interior, as well as moving structural elements that change the shape of the car completely. If the fabric can be rolled up somehow inside the structure, there's no reason why it wouldn't be possible to design a sportscar that transforms into a hatch - or even a wagon - when extra carrying room is needed, finally allowing the sportscar to become a practical everyday vehicle as well.

Naturally, the flexible fabric would have to prove itself in terms of durability, resistance to tearing, puncture and road debris, road noise reduction and overall vehicle safety before GINA ever made it to the market, but it's fair to say this is one of the most fascinating and fundamentally revolutionary design studies the auto world has seen for some years.

Loz Blain