Lightening-up time

A carbon-fibre concept car that weighs half as much as its metal equivalent and achieves 115 miles to the gallon is to be built in the UK early next year.

Researchers at Cranfield University are working to secure funding from the car industry to build the lightweight, super-efficient vehicle. They claim the vehicle will be 600kg compared to 1,200kg for a similar-sized car. It could achieve speeds of 95mph with a conventional 660cc petrol engine, the team claimed.

Associate professor Steve Cousins has been working on the project since it began in 1998. He believes the efficiency of his vehicle could compete with a steel-bodied electric/internal combustion engine hybrid such as the Ricardo/Valeon i-MoGen (The Engineer, 27 September). ‘We can get fuel efficiency as good as a standard car powered by a hybrid electric/petrol engine, because ours is lightweight with a low drag design.’

The body panels and space frame chassis of the Aerostable Carbon Car, as it is known, are made from carbon fibre. Another innovation is the lack of bonded or welded joints in the chassis. Instead, the frame is held together by a series of nodes. The frame itself is made from newly-designed braided fibre tubes, known as Coretex. These were developed as part of the Fast Frames sister project at Cranfield.

The tubes are snaked through the nodes in the vacuum mould. This is then sealed and the resin is infused into the tube as it is drawn around the mould by the vacuum.The bodyshell is to undergo wind tunnel tests next month. The design includes fins, bonnet inlets and extended wheel spats to stop the lightweight car being buffeted by winds. The space frame has so far had its production methods and crash resistance proven.

The method of manufacture is also viewed as an advantage. The project team claims that tooling costs could be cut by 95 per cent because the fibre’s moulds are so much cheaper than traditional press tools.

Robots will be used for building fibre components to cut production time. The companies involved in the current stage of the project include Ford, Lotus, Honda, various materials suppliers and Caterham Cars, with funding from the EPSRC Link programme. Changes in environmental legislation and subsequent industry agreements are pushing firms to develop more efficient vehicles.