A Feasibility Study of an ESG to Suppress Road Noise of a Car

Young-Sup Lee,Eunsuk Yoo,Chasub Lim,Seokhoon Ryu

doi:10.3390/app12052697

Young-Sup Lee, Eunsuk Yoo + Show 2 more

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https://doi.org/10.3390/app12052697

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Abstract

This study considered implementing an active road noise control (ARNC) system using an electronic sound generator (ESG) as a secondary actuator to suppress road noise in a car cabin. The ESG was installed to the cowl panel of a test car to generate structure-borne anti-noise by vibrating the panel. A robust multiple-reference single-input single-output (MR-SISO) ARNC algorithm based on the FxLMS was designed. Four 3-axis accelerometers and a microphone were adopted to acquire the reference signals and the error signal for the control algorithm. The radiated sound pressure from the ESG–cowl pair was high enough to suppress the road noise at a car speed of 60 kph. The optimized least number of reference signals and their locations were determined after computer simulation from the measured primary path data. Real-time control experiments showed an A-weighted sound pressure level reduction of 6.0 dB in the average of three dominant road booming noises in 100–250 Hz with the four optimized reference signals at 60 kph. More reference signals gave a further reduction such as 8.3 dB with 12 reference signals. Thus, this study suggests that the ESG coupled with the cowl panel can be an affordable alternative as a secondary actuator in an ARNC system to suppress road noise in a car.

Highlights

This study considered implementing an active road noise control (ARNC) system using an electronic sound generator (ESG) as a secondary actuator to suppress road noise in a car cabin
The frequency range for ARNC was determined to utilize 100–250 Hz where the magnitude was large enough to suppress road determined to utilize 100–250 Hz where the magnitude was large enough to suppress road noise and the coherence was sufficiently high as it reached almost 1. This indicates that noise and the coherence was sufficiently high as it reached almost 1. This indicates that the the ESG–cowl pair is an effective sound radiator at that frequency range in the car cabin
This paper investigated the feasibility of an ESG as a secondary actuator for an active control system to suppress road noise in a passenger car

Summary

Introduction

This study considered implementing an active road noise control (ARNC) system using an electronic sound generator (ESG) as a secondary actuator to suppress road noise in a car cabin. The radiated sound pressure from the ESG–cowl pair was high enough to suppress the road noise at a car speed of 60 kph. Real-time control experiments showed an A-weighted sound pressure level reduction of 6.0 dB in the average of three dominant road booming noises in 100–250 Hz with the four optimized reference signals at 60 kph. This study suggests that the ESG coupled with the cowl panel can be an affordable alternative as a secondary actuator in an ARNC system to suppress road noise in a car. For implementing an ARNC system including relevant electronics, the secondary actuators in active control are essential to generate anti-sound to suppress road noise. Proper actuators for this purpose are limited because of some practical reasons such as implementation cost, size, and weight [2]

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Conclusion