Research On Non-Steady-State Sound For China-Made Cars

With the popularity of automobiles in China, the issue of vehicle noise emerged gradually, according to the relevant data, it show that traffic noise pollution has been accounted for 75% in the environmental noise pollution . Car exterior noise is a major part of traffic noise. Vechicle noise which come from the streets every day harms to normal people study, work and rest. If long-term exposure in such an environment, it will affect the normal physiological. When the car exterior noise causes harm to the environment, its higher interior noise is easy to irritate and worry people, and even endanger traffic safety. Consumer's subjective feelings of the car noise have become one of the main factors to be considered, when they want to buy a car. This contributes to a number of automotive manufacturers for automotive sound quality research.Study of automotive sound quality is not only confined to people in the reduction of subjective annoyance caused by noise but also improve the Sound Quality and add some pleasant sound into car, it can increase people's comfortable when driving, In this paper, by studying the sound quality of nine cars of the domestic cars in the state to speed up, we establish the subjective evaluation of objective and quantitative model for car. Design a domestic car sound quality database, Its findings can promote the quality of car noise and guide the sound quality research.The article not only elaborate the human auditory system components and working principle and introduce the features of auditory system including loudness, characteristics of the band and masking effect in psychoacoustic but also explain objective evaluation of sound quality and the number of parameters.This paper introduces the sound quality process of an objective test, we collect noise signal of 9 car and use ArtemiS7.0 software to analysis and evaluate signal by objective methods. By analyzing the signals, we gain loudness, sharp, roughness, fluctuation strength, tonality, AI Index, linear sound pressure level and sound pressure level, etc. By comparing of objective assessment of each car results we know that the best sound quality belong to the eighth car. The results showed that the sound quality level of Chinese-made cars is high. We analyze the sound signals using of grading scale methods. SPSS software has been used to make the correlation analysis and multiple linear regression analysis for the value of subjective and objective, to establish the objective model for sound quality subjective, and passed the inspection. The results show that the sound quality is mainly affected by the effects of loudness and roughness in the state of the car to speed up. For sound quality parameters of objective evaluation and subjective evaluation, We design a Chinese-made car sound quality database management system. The database is a relational database. we design the database using c# and sql. Database greatly facilitates the sound quality management of the cars parameters. Data administrator can easily manage the operation of the data.