In-vehicle tire noise is an unwelcome intrusion that can travel through chassis components, such as control arms and dampers. At the Consumer Electronics Show (CES), ZF is presenting its new “Active Noise Reduction” software function, which reduces this type of noise at the source without additional noise dampening hardware in the vehicle. The purely software-based function for the chassis significantly minimizes annoying tire noise in the interior. In the future, the technology group will expand the use of the function to other ZF chassis actuators.
The software-based solution uses ZF’s Smart Chassis Sensor with an integrated acceleration sensor to precisely measure vibrations transmitted from the tires to the vehicle via the chassis. The vibration data is analyzed using a specially developed algorithm that recognizes the characteristic noise patterns of tire cavity noise (typically around 200 hertz). The software then generates a counter-signal provided by ZF’s cubiX software via the valves of semi-active dampers (CDC). The function uses micro-movements of the damper to specifically reduce the noise interference without impairing the actual damper function.
“Active Noise Reduction is an excellent example of how we use smart algorithms to make ZF components even more efficient. This gives our semi-active CDC dampers a clear unique selling point in the market and sets new standards in comfort – without the need for any additional noise dampening hardware,” says Dr. Peter Holdmann, member of the ZF Board of Management and head of Division Chassis Solutions.
Intelligent dampers, brilliant quietness: this is what the future of chassis technology sounds like
The achievement of noise reduction is implemented purely on a software basis through intelligent control of the CDC dampers – without additional installation costs or space requirements. The current version of the technology achieves noise reductions of more than 3 dB today – which is a clearly audible difference for passengers. Up to 10 dB is possible in the future.
Active Noise Reduction can be adapted to different vehicle types and customer requirements via software. This creates a new market, particularly for lower-priced vehicles – as high-quality acoustic solutions with microphones or speakers have mostly been available only in luxury segments. Approximately 40 percent of all semi-active dampers worldwide already come from ZF, making the technology group the market leader. In view of the trend toward automated driving, ZF expects sales in this area to increase.
Active Noise Reduction part of Chassis 2.0
Series production of Active Noise Reduction is scheduled to start in 2028. In the future, the software function may also be used in other ZF actuators — for example, for active reduction of brake squeal or in the fully active damping system sMOTION.
“Thanks to our system expertise, we are able to offer our mechatronic actuators as true innovation drivers with the help of smart algorithms and we will extend our software-based control approach to other ZF actuators in the future. The goal for us is clear: mechatronic actuators that are capable of efficiently reducing both their own and external noise with the help of software,” explains Holdmann.
The new function fits perfectly into ZF’s Chassis 2.0 product strategy. Chassis 2.0 uses intelligent and networkable actuators to enable new chassis functions via software. It combines intelligent actuators such as brakes, steering, and damping, scalable electronic architectures (E/E), and innovative software solutions into a highly integrated, flexible system. “With our Chassis 2.0, we are laying the foundation for the software-defined vehicle,” says Holdmann.
Captions:
• With its new Active Noise Reduction function, ZF is presenting a purely software-based solution at CES in Las Vegas that specifically reduces annoying tire noise in the vehicle interior – without any additional noise dampening hardware.
• The solution is based on the new generation of the ZF Smart Chassis Sensor with integrated acceleration sensor. This precisely measures the vibrations that are transmitted from the tires to the vehicle via the chassis. A specially developed algorithm recognizes the characteristic noise patterns of cavity noise and generates a phase-inverted counter signal.
