Electric vehicles are changing the way consumers understand vehicle comfort and quality. Electric vehicles have a significantly lower noise threshold compared to their conventional gas-powered counterparts. Therefore, it is important to pinpoint BSR (buzz, squeak, and rattle) issues in the passenger compartment before these vehicles hit the market. Here at MGA, we are determined to provide our customers with the highest quality sound data analysis. We aim to achieve this by constantly working to improve our lab equipment to ensure we are at the forefront of the industry standard.

SM Instruments / Sound Camera

Traditionally, BSR testing utilizes an electro-dynamic shaker table to induce frequency responses that can be detected through acoustic analysis either subjectively with the human ear or objectively using microphones. Engineers use these types of tests to evaluate vehicle components based on the noise they generate while in use.  Ref to: Vibrationresearch.com Some BSR issues can be difficult to locate, however. Even with multiple people evaluating a vehicle component, sometimes there is confusion as to exactly where a BSR issue is located. MGA Research has a state-of-the-art Sound Camera from SM Instruments that can help identify these problem areas by providing a visual sound pressure contour map. 

This Sound Camera incorporates an array of 30 microphones and a video camera that offers a new dimension to audio-video recording. The camera works in unison with the microphone array to generate a live sound pressure contour map which accurately pinpoints the emitted noise. Multiple noise hot spots can be displayed at the same time based on the sound frequency bandwidth selected.  

sound camera

Image Courtesy: SM Instruments

The SeeSV software which operates this Sound Camera is intuitive and easy to use. This software offers manual variation of band-pass filters and plays out live sound wave signals. This is extremely beneficial when there is a need to filter out background noise at low frequencies and isolate high frequency sounds from the tested component. Sounds emitted simultaneously or intermittently can be captured and seen live, all inside one window screen of the software.  

Once the required sound frequency is isolated and well-defined, pressure contours are generated. The software can record a video that displays the pressure contours and a colored severity map on your screen that signifies the direct location of the BSR issue. This allows you to revisit previously captured data and share test results (Audio-Video) with your team without them having to personally witness the testing and identify areas of concern. The equipment is best suited to capturing notorious sounds from seats, instrument panels, HVACs, heavy machinery, etc.

sound BSR article

This sound camera can perform tasks faster than a human evaluator and with greater accuracy. With efficient use of this equipment, valuable time can be saved in generating conclusions, implementing design changes, retesting, and deeming a part fit for production.

HEAD acoustics / Lab COMPACT12 

Our LabCOMPACT12 Frontend DAQ Unit from HEAD acoustics allows for use of up to 12 microphones (or other sensors such as accelerometers) at a time, enabling a complete coverage of a component under test. The captured sound recordings are processed using Artemis Suite and HEAD Recorder software to generate numerical values or graphical representations for different aspects of sound quality analysis. This quantification helps engineers gain further insights into sound produced by an in-vehicle component that is subjected to vibration input or operational noise. Proper analysis of this data can be used to determine whether a component meets manufacturer requirements or not.

sound head acoustics

Image Courtesy: Head Acoustics

HEAD acoustics / RPM Generator

In recent years, automotive seats have become more advanced with incorporated features such as fully automated adjustment motor functions, inflatable lumbar and bolsters, and cooling vents. These added functions have raised the bar for interior performance, as these features may add unwanted electrical noise to the cockpit. MGA has recently acquired an RPM Generator software from HEAD acoustics that can evaluate and detect very specific sound levels in motor rotation functions. With the RPM Generator, we can analyze the specific sound modulations emitted by these motors.

The algorithm developed by HEAD acoustics allows users to generate missing RPM signals from order curves with little effort, and to add them as new channels automatically. Using the Batch RPM Generator, this process is applied to a larger number of measurements simultaneously. This allows users to generate RPM curves for many similar measurements at the touch of a button.

The algorithm even detects the correct revolution speed for measurements of different lengths, keeping manual adjustments to a minimum. When measuring rotating objects, such as small motors or turbochargers, it is often very difficult to measure the revolution speed. In such cases, the RPM Generator allows users to generate these missing RPM signals, e.g., from structure-borne noise signals, and to embed them in the recording as new channels, with simple means and a short investment of time.

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sound data2

In conclusion, to keep up with the ongoing changes constantly happening in automotive manufacturing, MGA Research always has and always will continue to improve upon our lab capabilities based off our customers’ requirements so that way we will always be your dedicated test lab, validating the future together.