“The concept isn’t difficult to understand,” said Dirk Landheer, managing director of Simpact, which came up with the idea. “The flexible wishbones attach to the chassis and their internal structural design controls the wheel movement. However, suspension systems move in a variety of directions, not just up and down, so it’s highly complex in detail. Only now that we have access to a great deal of computer power has it been possible to analyse and prove the system in all conditions.”
Manufacturing the critical composite suspension arms
is also complex, explained Landheer. The parts need very careful hand lay-up at present, with the direction of the fibres and the wishbones’ thickness very precisely controlled.
By applying dozens of sensors to the basic structure of a standard Atom, and using the University of Warwick’s measuring apparatus to record the car’s behaviour, the partners were able to gather large quantities of data about the basic functioning of a conventional suspension system and then apply it to the design of Lift.
The partners were encouraged by early experiments that flexible suspension arms could replace springs, but discovered a need for much more precise damping. Experiments will proceed with suspension
arms incorporating piezo fibres (which can change
their bending behaviour when electrified) that have the potential to provide improved damping without any need for a classic tubular damper.
Looking further down the road, the partners believe the converse ability of piezo fibres to generate electric power through movement — in this case, the action of bumps on the suspension — may produce enough energy to make a worthwhile contribution to
the propulsion of a whole vehicle. “We got interested in this because, though this was disruptive technology, we could see it working,” said Ariel boss Simon Saunders. “We’re always open to new ideas; in fact, if it works, we could be one of the first adopters.”
The work on Lift so far revealed is the product of a year’s backing from Innovate UK. The next stage would be to build a running Atom prototype, but the go-ahead for that awaits the results of further funding competitions.
Though the first Lift parts will be tested on an Atom, Landheer says the system should allow designers great flexibility in devising future suspensions. Configured for a service life of about 620,000 miles, Lift should have no serious durability problems and be applicable to both light and heavy vehicles. It should also afford designers the opportunity to go for sporty or luxurious suspension — or anything in between.