When the AVAS1 switches off from a speed of about 20 km/h, electric cars drive quietly – a great achievement. However, this results in a new challenge: Unwanted noises in the interior of vehicles, caused by tires, chassis and bodywork, are now more noticeable and usually unpleasant with the quiet electric motor.
We are supporting Volvo Cars in optimizing the all-electric premium SUV EX90 with regard to "NVH" (noise, vibration, harshness). This refers to the audible or perceptible vibrations in the vehicle, especially on uneven road surfaces.
For this purpose, Volvo Cars uses our VESPA electric vertical dynamic structural test bench, equipped with a special safety system for battery-powered vehicles. The acoustics of the entire structure, all add-on parts and above all the interior are tested under simulated mechanical and climatic loads as well as sunlight with regard to any noise that may be present.
Tests in climatic chambers with sun simulation are essential here in order to be able to test the effectiveness of optimization measures even under extreme climatic conditions. All relevant environmental conditions are simulated in order to be able to analyze and optimize a wide variety of noise sources in the entire vehicle, from "Alaska to Africa" at very low or high temperatures.
The special feature of the 4-poster VESPA: Due to the electrical actuators, the test bench operates so quietly that disturbing noises can be determined not only in the interior, but also on the outside of the vehicle. Due to its extremely powerful actuators, VESPA achieves retraction qualities that are very difficult or impossible to achieve with hydraulic test benches. The requirements of our customer regarding environmental conditions (temperature, humidity and sun) as well as mechanical load can be covered with the VESPA simultaneously and partly above the required accuracies.
Another unique selling point is the possibility to perform tests on electric vehicles with a charged battery.
Details about VESPA can be found here on our website.
1 Acoustic Vehicle Alerting System