Cambra Semi-Anecoica 1 low NVH Vehicle Development

Applus+ IDIADA is an independent partner for the automotive industry with extensive capacity for management and resolution of NVH (noise, vibration and harshness) development projects.

Advanced tools for testing and simulation, a highly experienced team, integrated within a whole vehicle performance department and management network for global development projects, which provide us with unique characteristics to carry out successfully global NVH projects.

Applus+ IDIADA offers a wide range of activities that allow us to take into account the NVH performance at any stage of the vehicle development project:

  • Vehicle concept and target definition
    • Benchmark measurement programs
    • Establishment of project targets – Target book
    • Analysis of design concepts
  • Development and testing
    • Design validation plans
    • Subjective assessments
    • Measurements and troubleshooting for the full-vehicle NVH performance: combustion noise, intake and exhaust noise and vibration measurements, door slam, brake noise, tire noise, noise from HVAC units.
    • Measurements to support CAE development and correlation: body-in-white and trimmed body modal analysis, NTF and Dynamic stiffness measurements, noise and vibration isolation measurements, structural acoustic cavity modes.
    • NVH target validation
    • Troubleshooting and tuning
    • Component validation

 

Noise and vibration measurements are performed either in Laboratory or test tracks.

NVH testing tracks

The test tracks are normally used to assess the general noise and vibration performance of the vehicle. Test tracks which we use for NVH purposes include the following:

  • High speed circuit

The high speed circuit is used for on-vehicle NVH general assessments and measurements due to its smooth surface. The optimal conditions of the asphalt, its length and good weather conditions are the key aspects that make this facility very attractive for our clients.

  • Deterministic inputs test track

This track provides a complete variety of transient inputs. It is used to assess and measure the vehicle comfort performance when the vehicle drives over a known input surface.

  • Road noise test track

This rough asphalt section consists of two parallel strips which are 300 m long and 1.2 m wide. With a 0.8 m space between them. The asphalt is a hot bituminous mixture which is quite common on British roads, and is defined by the BS 594 standard.

  • Comfort test tracks

Comfort test tracks surfaces provide a complete variety of surfaces for ride comfort, rattles, squeaks, suspension steering vibration and noises.

  • Exterior noise test track

The exterior noise test track provides is an excellent facility to measure the pass by noise. Due to its approaching and departure length, the ISO surface allows measuring any kind of vehicle, including buses and heavy trucks.

 

NVH Laboratories

The NVH laboratories are used to reproduce NVH issues on full vehicles, systems and subsystems. Measurements, assessments and troubleshooting are performed in our facilities. Laboratories  we use for NVH purposes are  the following:

  • Semi-anechoic vehicle dynamometer

The vehicle semi-anechoic chassis dyno is used to perform any type of tests that requires no extraneous noise and vibration events. The room is completely isolated form the rest of building and the dyno roller is capable to reproduce the driving conditions existing in the tests tracks. The noise absorbing wedges installed in the walls and ceiling avoid noise reflection and allows measurements in a free field condition.

  • Modal analysis test bench

The modal analysis test bench is placed in a quiet room and is suitable to perform modal analysis over trimmed body and body-in-white. Also measurements are performed over systems and sub-systems.

  • Four posts bench

The four posts bench is especially useful to apply a known input to the vehicle wheels. This allow us to investigate multiple vehicle issues. Some examples are body resonances or squeaks and rattles.