Application: cabin noise measurements

The optimization of a vehicle cabin noise quality is a priority for car manufacturers. Nearfield acoustical holography already proved to be efficient to deal with this problem during the various development phases of a vehicle. It can quantify the acoustic leaks or the soundproofing weaknesses, and by the same time, locate these failures with such an accuracy that the processing of these defects is thus made much easier to the design engineers. The result is visualized by colors' spots that software like dBVision can display on top of a numerical pictures or a diagram of a part of the cabin under study: it all becomes clearer to understand for the design office.

The industrialization of this method needed the elaboration of reliable economic procedures to carry out the tests. Indeed, the tests must be run under various loading conditions in order to allow the quick evaluation of improvement solutions and/or the benchmarking between competitor vehicles of the same segment...

As such requirements imply in the first instance the measurements' automation and reliability, the market is naturally waiting for a robot-based solution. This removes any sensors' manipulation, complex and time consuming, and guaranties a perfect repeatability of the analysis.

With the development of the IPS (*) system, 01dB-Metravib had already acquired experience. Then in close collaboration with the NVH department engineers from DaimlerChrysler in Detroit (USA),
01dB-Metravib developed the measurement means the market was waiting for, to carry out the complete scan of the vehicle cabin in a totally automatic way and within a record time: less than 30 minutes for the two front doors and the windshield! This new tool combines the unique abilities of the dBVISION acoustical imaging system with the flexible use of a compact robot placed inside the vehicle. It now allows performing the most accurate acoustical analyses in the respect of your time, security and cost constraints.

This system is now a product of the 01dB-Metravib robot range, which can be used in any type of cabins (aircraft or helicopter cockpits, train or truck cabins, ...)

(*) 3D Instrumentation Positioning System, (patent n° FR 02 12456 (2 845 510))

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