No more shaking on start-up, no revving of the engine in the case of quick take-off from traffic lights, and no monotonous humming during long freeway driving. Noise and vibration that drivers currently regard as perfectly normal are suddenly a thing of the past in the case of electrically powered vehicles. Noise and vibration previously covered by the combustion engine now disturb this newly found silence. This personal impression of each passenger will be intensified if nobody is playing the active role of driver in the future, as everybody in the vehicle will be more sensible for vibration and noise.
E-mobility: silent is not really silent
Electric vehicles may be quieter, but their drive creates vibrations in a frequency range that is more unpleasant for humans. One such example is that combustion engines produce vibrations of between 20 and 400 Hz, while electric engines produce vibrations of over 10,000 Hz. At the same time, previously unheard noises come to the fore, such as rolling and wind noise, or previously unnoticed noise sources like the air conditioning compressor.
The use of new vibration control technology specially developed for the requirements of electrically powered vehicles is required. Current vibration control technology solutions are only able to partially cover these new conditions from a purely physical perspective.
“This may result in completely different damping characteristics of the products used. New solutions will then offer the same, or even greater, level of comfort as in current vehicles. Highly robust chassis mounts and innovative air spring systems from Vibracoustic, for example, are already responding to these new challenges,” says Dr. Jörg Böcking, CTO at Vibracoustic.
Autonomous driving: an uncomfortable future?
It is a fascinating vision: self-driving vehicles organizing themselves in such a way that traffic levels and accident numbers are reduced. Passengers can make productive use of their time, reading the newspaper or working. However, this is one of the major challenges facing autonomous driving, as productive use of time is only possible if passengers are not battling with a feeling of discomfort. No matter how interconnected the systems are and how sophisticated the safety technology is, autonomous driving will only be really accepted if passengers can feel at ease and comfortable while being driven.
Vibration control technology has an important role to play in this. During a transitional period, it needs to take two very different scenarios into account. First, the classic scenario, with the chassis tuning focused on the driver. It defines the dynamic properties and the driving feeling that is so vital in the purchase decision. But once the vehicle switches to autonomous driving operation, this configuration needs to change completely. Disruptive noise is damped, with vibration and impact reduced.
“This comfort mode places the focus on passive passengers. This is a necessary paradigm shift for autonomous driving to be regarded as an enjoyable experience. Already today, switchable air spring systems offer a wide range of adjusting options,” says Dr. Jörg Böcking, CTO at Vibracoustic.
Entertainment services, such as screens integrated into the seats, are another example. Here, vibrations need to be compensated by means of seat dampers to ensure a pleasant, smooth entertainment experience.
Road network 4.0: decentralized monitoring of road damage
Just a click of a mouse is all it takes for ESA and NASA ground stations to check the condition of every part of their satellites located thousands of miles away in space. Meanwhile, on our doorstep, street construction authorities sometimes use pins on maps to mark road damage. Large routes are monitored with considerable use of resources, while authorities rely on complaints from road users in the case of secondary roads.
Future innovations in vibration control technology include active damping components fitted with sensors, identification of shock through road damage, linking of this information with precise GPS data, and uploading it to the cloud. From there, the relevant authorities or operators can obtain a comprehensive real-time image of the condition of their roads. The interconnected vibration control technology in vehicles not only helps to record road condition, but also to improve comfort in the vehicle.
“Vibracoustic already has adaptive and active vibration control technology, which counteracts the various vibrations and balances them out. In the future, a chassis will be able to adapt to current road conditions in real time using data from the cloud, for example” says Dr. Jörg Böcking, CTO at Vibracoustic.