This “metamaterial” developed by Nissan is based on a plastic structure, light and capable of attenuating low-frequency vibrations like those produced by the road and the engine. A particularly interesting innovation for electric vehicles.
The soundproofing of the car is a technical challenge for engineers. They must at the same time use efficient materials, not too bulky or too heavy and economically viable on an industrial scale. The most important noises to seal are those of the engine and the contact of tires on the road. Currently, rubber panels are one of the main insulators used in the automobile. But Nissan researchers have come up with an alternative that looks promising.
The Japanese car firm came to present at CES 2020 an ” acoustic metamaterial ‘very light and able to limit the spread of the cabin noise to broadband of frequency (500-1200 Hz ), such as road and engine. Behind this somewhat obscure description hides a relatively simple process: a honeycomb structure applied to a plastic film. When the sound comes into contact with such a panel, it will bounce off the material, which considerably reduces the level of sound which manages to pass through the insulation.
An economically viable material
In addition to its efficiency, Nissan’s new acoustic material weighs a quarter of the weight of traditional sound insulation. This gain is particularly interesting in the case of electric vehicles since it can help improve performance and range.
In addition, Nissan underlines that the cost of mass production would be almost equivalent, even better than that of current materials. This insulation could be used in categories of vehicles where this type of protection is usually limited for reasons of cost or weight.