Active structural control on a car for cancellation of road noise disturbance

摘要

An active structural control strategy is applied to the structure-borne road noise trans-mission paths on a car in the laboratory. A methodology is first presented for the real-ization of a vibro-acoustic model of the car using measured primary and secondary Fre-quency Response Functions (FRFs). Primary FRFs are characterized between the ex-citation signal at each wheel and each suspension/chassis linkages and secondary FRFsare characterized between the excitation on different locations at each suspension andeach suspension/chassis linkages. Vibro-acoustic FRFs are also measured between theexcitation (primary and secondary) and the acoustic pressure inside the car cabin. Anexperimental model of the car is used to simulate the configuration of the active con-trol system, using the primary FRFs and secondary FRFs. A genetic algorithm is thenused to optimize the configuration of the control actuators. Optimal control results sim-ulate the noise reduction achieved by the approach in the cabin using candidate costfunctions. A prototype of the active control was then implemented on the car and mea-surements were performed in order to assess the performance of the control approach.More than 10 dB attenuation on acoustic field inside the car was obtained at some fre-quencies. Finally, road excitation was used to simulate the active control performanceon real conditions (car rolling at 50 km/h). Optimal control results show more than17 dB(A) global attenuation inside the cabin between 20 Hz and 500 Hz.