Objective Identification Of Subjective Sound Quality In Passenger Cars During Acceleration

This paper study the objective identification method to judge subjective feeling of speed up sound quality.Considering present research situation in this field,a method to evaluate subjective sound quality features is established.Objective parameters of speed up sound quality are analyzed,and mathematical model between subjective feeling and objective parameters is set up through strict statistical methods.This mathematical model can provide a theoretical basis for directing the speed up sound quality design.Determination of sound quality subjective parameters and construction of noise samples.Subjective evaluation parameters are determined by literature research ?questionnaire and statistical analysis.The felling of smooth?weak of oppression?clean?quiet?no harsh felling and hard are defined in subjective evaluation parameters which are more refined than the same research field.Ten reference vehicles were selected for the interior noise acquisition determined by the vehicle type,the displacement and the noise level to get noise sample.In order to ensure the representativeness and rationality of samples,refer to the actual requirements of the national standard,Dongfeng enterprise standard and sound quality research,as far as possible to eliminate the interference to evaluation caused by the shift difference,engine speed difference and the difference of power assembly,developing the acquisition process and processing methods of sound samples,and the evaluation samples of sound quality are determined.The implementation of subjective evaluation of sound quality.The subjective evaluation was performed by using the paired comparison method(the general evaluator)and the grading method(the professional evaluator).In order to ensure the accuracy and stability of the results,a set of test results(reverse sequence test,triangular cyclic test,Spearman correlation coefficient test,Grubbs criterion,etc.)was established and the results of the evaluation were quantified(Bradley-Terry model method).At the same time,in order to verify the effectiveness of the results,the results of the subjective evaluation using those two methods were compared and found that the Spearman correlation coefficient is greater than 0.8,with high consistency.The results of this study reflect the reliability of the evaluation method and its test criteria,and ensure the correctness of the subjective evaluation results,which provides the support for the accuracy of the model.The subjective feeling of sound quality will be objective quantification.Based on the existing research results and combined with the noise characteristics of vehicle acceleration,the objective parameters of acoustic quality are studied from two aspects of the psychoacoustic and physical acoustics.The objective parameters were screened and analyzed by objective and subjective analysis and statistical analysis,and then the objective parameters of acoustic quality,which were directly related to automobile development,are determined.These parameters can better reflect the quality characteristics of the car when the acceleration,but also more conducive to the later car sound quality design.The establishment of subjective and objective assessment relation model of sound quality: On the basis of subjective assessment and objective parameters determined,analysis the advantages and disadvantages of different modeling methods,finally establish the relationship model between the subjective and objective via using multiple linear regression method;Establish six subjective and objective relationship model for the above six groups of subjective assessment parameters.These models can be used well to guide the design and development of accelerated sound quality.