New, ‘smart’ solutions to drone out those annoying car noises

The droning of a car is just one of the annoying noises cars make but now 11 Fraunhofer Institutes have joined forces to create the ‘Adaptronics Alliance,’ making new, "smart" solutions so that you have a more enjoyable drive.

Researchers use piezoceramics, a material that transforms electrical energy to motion and conversely dampens vibrations by converting them to electrical energy.

The piezo bearings are electromechanical energy transducer devices, being electronically controlled to counteract and neutralize these bothersome vibrations.

In an opposite approach, researchers are developing piezo components that convert the oscillations in a structure - such as within high-traffic bridges - to electrical energy.

This energy can be used to supply tiny - energy-autarchic sensors that can monitor the condition of the bridge and notify a control center of any damage.

An alternative material are ‘magneto-rheological fluids,’ which contain tiny particles that align themselves to form fixed chains in a magnetic field. The fluid solidifies and depending on the strength of the field, the fluid is hard, viscous or watery.

The Alliance partners have used it to develop a safety clutch for machinery - for use in motor vehicle drives or milling machines. During operation, the fluid is solid. In this state, it creates a solid linkage between drive shaft and cutter head. Activating the emergency shutoff button switches off the magnetic field. The substance returns to its fluid state. The drive shaft spins freely. The cutter head comes to a standstill.

"The technology is ready. Work is moving forward on other exciting solutions - from mechanical engineering to the consumer-goods market," notes head of the Alliance Tobias Melz of the Fraunhofer Institute for Structural Durability and System Reliability LBF in Darmstadt.