Feel the vibes

Driving is a sensory experience. Even the most pragmatic driver doesn’t think of their vehicle as a way of getting them from A to B - the feel of the car and particularly the sound are important. This poses a problem for car makers. How can they ‘design-in’ acoustic performance in their new cars? Germany’s Fraunhofer Institute is trying to find out.

Acoustic performance is determined on a variety of rolling road-test rigs. The cars sit with their wheels on revolving drums, whose surfaces are covered with strips of different road surfacing materials. This allows the makers to test performance at different speeds. However, the systems are bulky, costly and can be dangerous at high speeds.

Also, they can only test perfect road surfaces. If you want to find out what happens if the car goes over a pot-hole or any other source of vibration, you need a different rig that tests the car’s suspension with hydraulic systems.