World-first noise tech revealed by Hyundai

VEHICLE cabin noise-cancelling systems have been around for years, but now Hyundai Motor Group is claiming a breakthrough with a system it says can detect and counter road noise in 0.002 seconds.

The South Korean company says the world-first active noise control technology can cut road noise by up to 3dB and can even render electric and fuel-cell vehicles “nearly silent”.

Set to make its debut on a future unnamed Genesis model, the system is claimed to be so effective that Hyundai says it might be able to reduce the weight of its cars by cutting back on insulation and noise-reducing dampers.

In a collaborative project taking six years, Hyundai worked with Korean scientists to develop the sophisticated sensors and software for Road Active Noise Control (RANC), and then worked with global audio system manufacturer Harmon to bring it to production.

Announcing the system in South Korea, Hyundai said current noise-cancelling systems – some of which are used on current Hyundai models – were limited due to the limitations of noise measurement and analysis technology that had trouble countering engine and road noise waves that reached the cabin in 0.009 seconds.

The new system uses an acceleration sensor to calculate road vibration, helping the control computer to analyse and then – via an inverted sound wave – combat the noise in just 0.002 seconds.

The system can even adjust its noise-countering waves to maximise the effect in each of the seating positions around the car.

A microphone monitors the cabin noise, sending signals to the digital signal processor.

“Based on tests evaluating road surface, vehicle speed, and different seating positions, RANC was able to reduce in-cabin noise by 3dB,” Hyundai said. “That 3dB level is roughly half the noise level as compared without RANC.”

Hyundai says it sees road noise cancellation as an imperative as vehicles move towards electric and fuel-cell powertrains that emit little noise compared with internal-combustion engines.

The company has patented the system around the world as it prepares to roll it out, first on its luxury Genesis fleet.

Like many technologies adopted by car manufacturers, active noise control was first employed on aircraft, with the first experimental systems developed in the 1950s.

The first car credited with such a system was the Nissan Bluebird in 1992.