Ensuring the acoustic and vibration performance of a vehicle is hugely challenging and requires expertise in a range of noise vibration harshness (NVH) performance domains. To achieve fast and efficient response, automotive OEMs sometimes choose to outsource the responsibility for NVH vehicle integration.
We have worked with a number of customers where we have taken full responsibility for the development of all aspects of noise and vibration in the vehicle programme and have acted as the noise and vibration lab.
Activities range from initial subjective and objective benchmarking, vehicle-level and system/component-level target setting, NVH troubleshooting and development to achieve programme targets and launch support.
Projects include initial subjective and objective benchmarking, vehicle-level and system/component-level target setting, NVH troubleshooting and development to achieve programme targets, and launch support.
Here are some projects and project elements we have worked on with customers:
A software and services company working with an automotive OEM requested that we assess (experimentally) all the cabin acoustic cavity modes in a vehicle, up to 150 Hz, to achieve better correlation between test and Computer-aided engineering (CAE) analysis.
Stationary acoustic and vibration measurements were conducted in a hemi-anechoic chamber. Vehicle body panels were instrumented with accelerometers and several microphones were positioned in the cabin. For the acoustic artificial excitation tests, a low-frequency volume velocity source was placed behind the rear seats. For the structural artificial excitation tests, a rear wheel was removed and a shaker positioned to excite at a rear suspension attachment point. Measurements were made at customer-defined locations with different trim configurations, from fully trimmed to completely bare. Complete datasets of acoustic, structural and vibro-acoustic transfer functions (V/F, P/F, V/Q, P/Q) were taken for each trim configurations and provided to the CAE team for correlation.
Vibration energy from an engine travels into the structure, through the engine mounts, and through the car seat into the driver. But energy from the same source can take a similar path through the structure to become acoustic noise when it is amplified by the cabin. Both interior and exterior noise are critical and subject to regulation. There can be too much or – in the case of EV's – too little noise. Noise and vibration characteristics of components, sub-assemblies and the entire vehicle need to be tested at an early stage of development to avoid costly design changes and a delayed go-to-market. Therefore, optimizing these factors is not only of utmost importance for the overall user experience of the vehicle, it also ensures the finished product will meet noise emission targets and certification requirements. HBK offers a comprehensive suite of best-in-class NVH test equipment and highly skilled engineering service.