A test method for structural road noise transfer function

Abstract

The invention discloses a structure road noise transfer function test method. The signal-to-noise ratio of a signal can be remarkably improved by sequentially applying periodic pulse excitation onto each wheel, and the strong coherent excitation input and influence of background noise on structure noise transfer function estimation are reduced by a windowing the measured signal. Compared with the prior art, the structure road noise transfer function test method proposed by the invention has the advantage of higher accuracy, is simple and convenient to operate and has relatively high application value in aspects of automobile road noise transfer function test and transfer path analysis.

Description

technical field [0001] The invention belongs to the technical field of automobile NVH (English abbreviation of Noise, Vibration, Harshness) experiment, and in particular relates to a test method of structural road noise transfer function. Background technique [0002] The noise in the car has a direct and important impact on ride comfort, which reflects the core competitiveness of automotive products, and is highly valued by both the automotive industry and academia. The main components of interior noise are tire / road noise, power / drive train noise, wind noise, etc. According to different sources and transmission media, tire / road noise can be divided into air noise and structure noise. Air noise is caused by the mutual circulation and disturbance of the air around the tire when it rotates. Structural noise in tire / road noise (referred to as structural road noise) is generated by the vibration of the vehicle body caused by the excitation of the road surface through the tire...

AI Technical Summary

Problems solved by technology

However, the traditional TPA needs to disassemble the system, the test preparation is cumbersome, time-consuming and labor-intensive, and the vehicle cannot reflect the dynamic nonlinear transfer characteristics of the suspension in the static state, so the transfer path analysis method (OTPA-Operational Transfer Path Analysis) was proposed. By testing the excitation source response and the target point response under the actual working state of the system, and calculating the transmissibility matrix between the two, the contribution of each transmission path can be obtained without identifying the actual vibration source. Excitation load

Compared with the traditional TPA, OTPA greatly reduces the test workload and improves the efficiency significantly. It can simultaneously identify structure-borne road noise and air-borne road noise. However, due to the strong coherence between the excitations input to the four wheels, the input signal Since the power spectrum matrix is ​​singular, it will cause a large error in the calculation of the transfer function

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