JP2008298474A - Sound quality evaluation device and method for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly and quantitatively evaluate with reproducibility a feeling of concord relative to various sounds generated from a vehicle. <P>SOLUTION: A measured sound, an evaluation object, is subjected to order analysis, and the inclination of a straight line to a sound pressure level of an order component which is a fundamental tone of the evaluation sound subjected to the order analysis and an order component which is a harmonic sound thereof is determined as an analysis tilt angle x, and the feeling level of concord is determined by a feeling-of-concord quantitative evaluation expression formed by including operation terms with respect to each of a difference between the analysis tilt angle x and an ideal tilt angle xr stored beforehand, a total value NL0.5 of 0.5 order pitch background noises, and a main order level sum total value S. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicular sound quality evaluation apparatus and a vehicular sound quality evaluation method for evaluating a feeling of sound harmony at an exhaust outlet of a vehicle, a driver seat ear position, and the like.

Conventionally, various techniques for evaluating the transmission sound of a vehicle have been proposed. For example, in Japanese Patent Application Laid-Open No. 2002-123261, various evaluation words (“comfortable”, “crisp”, “linear”) based on auditory sensibility in a database and sound levels corresponding to predetermined machine elements are recorded. It has acoustic characteristics data such as frequency spectrum, correlation table between engine speed and noise level, measurement of noise level of sound received by the sound receiving unit, periodic sound caused by engine sound, non-periodic sound caused by running A technique is disclosed in which analysis such as measurement is performed and an evaluation word and an evaluation value are calculated by referring to a database of these analysis values.
JP 2002-123261 A

  By the way, there is a thing called “consonance” as one element that makes a sound feel beauty. Conventionally, evaluation of this “consonance” in a vehicle has been evaluated by a sensory method by a skilled evaluator. However, the sensory method has a large evaluation variation due to individual differences of the evaluator and changes in physical condition, and a quantitative evaluation method with reproducibility is required. In the evaluation method disclosed in Patent Document 1 described above, an example in which an evaluation value of “linear feeling” is calculated by calculating a displacement amount from a regression line in order to evaluate a “linear feeling” sound is disclosed. However, there is no disclosure about the evaluation of the “consonance” of the sound, and there is a strong demand for the development of an appropriate quantitative evaluation method with reproducibility for the “consonance”.

  The present invention has been made in view of the above circumstances, and a vehicle sound quality evaluation apparatus and a vehicle sound quality evaluation that enable appropriate quantitative evaluation with reproducibility for a sense of harmony regarding various sounds generated in a vehicle. It aims to provide a method.

  The present invention provides an order analysis means for performing order analysis of the evaluation sound to be evaluated, and an ideal inclination angle of a straight line with respect to the sound pressure level of the order component serving as the fundamental tone and the order component serving as a harmonic thereof, as an ideal tilt angle. An ideal inclination angle storage means for storing, an analysis inclination angle calculation means for obtaining, as an analysis inclination angle, an inclination of a straight line with respect to a sound pressure level of the order component which is the fundamental sound of the evaluation sound subjected to the order analysis and a harmonic component thereof; A quantitative evaluation means for preliminarily setting an evaluation formula for quantitatively evaluating the cooperative feeling of the evaluation sound based on at least the ideal inclination angle and the analytical inclination angle, and quantitatively evaluating the cooperative feeling of the evaluation sound based on the evaluation formula; It is characterized by having.

  According to the vehicle sound quality evaluation apparatus and the vehicle sound quality evaluation method according to the present invention, it is possible to perform appropriate quantitative evaluation with reproducibility for a sense of harmony regarding various sounds generated in the vehicle.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 8 show an embodiment of the present invention, FIG. 1 is a block diagram showing the overall sound quality evaluation apparatus for a vehicle, FIG. 2 is a flowchart of a sound quality evaluation program, and FIG. FIG. 4 is an explanatory diagram showing an example of the order analysis of the evaluation sound, FIG. 5 is an explanatory diagram showing an example of the analysis of the interior sound of the 4-cylinder engine, and FIG. 6 is the interior of the 6-cylinder engine. FIG. 7 is an explanatory view showing an example of sound analysis, FIG. 7 is an explanatory view of evaluation sound evaluation, and FIG. 8 is an explanatory view of an example of displaying sound quality by engine speed and frequency.

  In the present embodiment, the sound quality evaluation process of the vehicle is performed by executing a processing program described later in a computer system such as a personal computer (hereinafter abbreviated as PC).

  As shown in FIG. 1, a PC 1 that is a sound quality evaluation apparatus for a vehicle includes a computer main body 2 that includes a central processing unit (hereinafter abbreviated as a CPU) and a storage device that stores various data and programs, and the computer main body 2. And a keyboard 3 that is a key input device, a mouse 4 that is a pointing device, and a monitor 5 that is a display device.

  In the computer main body 2, a sound quality evaluation program described later is recorded in a built-in HD (Hard Disk).

  The HD built in the computer main body 2 has a plurality of ideal tilt angles xr in advance, with the ideal tilt angle of the straight line with respect to the sound pressure level of the order component serving as the fundamental tone and the harmonic component serving as the overtone as the ideal tilt angle. Is remembered.

  These ideal inclination angles xr are set in advance through experiments or the like. For example, for a four-cylinder engine vehicle, the fundamental order is a 2.0th order component, and its harmonic component (4.0th order component, 6.th order component). The ideal inclination angle of the straight line with respect to the sound pressure level corresponding to the 0th order component, the 8.0th order component, ...).

  As an ideal inclination angle corresponding to a 6-cylinder engine vehicle, the fundamental order is a 1.5th order component, and its harmonic components (3.0th order component, 4.5th order component, 6.0th order component...) The ideal inclination angle of the straight line with respect to the sound pressure level corresponding to and the fundamental order is the 3.0th order component, and its harmonic components (6.0th order component, 9.0th order component, 12.0th order component,... ) Are stored as two kinds of ideal inclination angles of the straight line with respect to the sound pressure level corresponding to.

  The data of the evaluation sound to be evaluated is supplied through a recording medium such as an FD (flexible disk), a CD (Compact Disc), a DVD (Digital Versatile Disk), and the like. Sound quality evaluation is executed according to a sound quality evaluation program described later. This evaluation sound is a sound acquired by a microphone provided at an ear position in a driver's seat or a passenger seat in the passenger compartment, or exhaust noise measured at the exhaust outlet of the vehicle.

  Specific sound quality evaluation executed according to the present embodiment will be described with reference to the flowcharts of FIGS.

  First, in step (hereinafter abbreviated as “S”) 101, an evaluation condition is input for an evaluation sound to be evaluated. Specifically, this evaluation condition is the evaluation position of the evaluation sound (for example, the position of the ear in the driver's or passenger's seat in the passenger compartment if the sound is in the vehicle, or the position of the exhaust outlet of the vehicle if the exhaust noise. ), A sound that is generated during full-open acceleration, a sound that is generated during slow acceleration, and a condition for evaluating a sense of harmony such as an engine speed range.

  Then, the process proceeds to S102, where the evaluation sound is measured under the evaluation conditions of S101 described above, and the measured evaluation sound is recorded on a recording medium such as FD, CD, DVD, etc., and the computer main body 2 is recorded from these recording media. Recorded on the HD.

  Next, the process proceeds to S103, and the above-described recorded evaluation sound is subjected to order analysis at a 0.1th-order pitch, for example, as shown in FIG. That is, S103 is used as an order analysis means.

Next, the process proceeds to S104, and a sense of harmony level calculation process is performed using a sense of harmony quantitative evaluation formula.
As shown in the flowchart of FIG. 3, first, in S201, whether or not the sound pressure level of the secondary component is higher than the sound pressure level of the tertiary component is calculated in S201. If the sound pressure level of the secondary component is greater than the sound pressure level of the tertiary component, it is determined that the sound is related to the 4-cylinder engine and the process proceeds to S202, where the fundamental order is set as the secondary component, A higher order component is discriminated as a harmonic component (an example is shown in FIG. 5).

  Conversely, if the sound pressure level of the secondary component is determined to be equal to or lower than the sound pressure level of the tertiary component, it is determined that the sound is related to the 6-cylinder engine, and the process proceeds to S203, where the sound pressure level of the 1.5th component is determined. Is compared with the sound pressure level of the 6.0th-order component.

  As a result of the comparison in S203, if the sound pressure level of the 1.5th order component is higher than the sound pressure level of the 6.0th order component, the process proceeds to S204, where the fundamental order is set to the 1.5th order component, and the higher order component. As a harmonic component (an example is shown in FIG. 6A).

  Conversely, if it is determined that the sound pressure level of the 1.5th-order component is equal to or lower than the sound pressure level of the 6.0th-order component, the process proceeds to S205, where the fundamental order is set to the 3.0th-order component, and the higher-order component is the harmonic component. (An example is shown in FIG. 6B).

  That is, in the case of a 6-cylinder engine, a 1.5th order component is recognized as a fundamental sound and a harmonic component is recognized as a vehicle sound, and a 3.0th order component is recognized as a fundamental sound and a harmonic component is recognized as a vehicle sound. This is because there are two cases where the two cases are performed, and therefore, an evaluation that can appropriately deal with the two cases is performed. In this embodiment, the sound pressure levels of the respective order components are compared by the processing of S201 to S205 to determine the fundamental order and its harmonic component, but are given in advance as initial conditions for evaluation. You may do it.

  After the fundamental order and its harmonic component are determined in S202, S204, or S205 described above, the process proceeds to S206, and the peak level inclination angle (analysis inclination angle) x is calculated for the fundamental order and its higher order components. .

  For example, in the case where the fundamental order is a 2.0th order component and its higher order component, as shown in FIG. 5, the 2.0th order component, 4.0th order component, 6.0th order component are used as the inclination angle of the peak level. The straight line Lx that approximates the sound pressure level of... Is calculated by, for example, the least square method, and the inclination angle (analytical inclination angle) x of this straight line is calculated.

  In the case where the fundamental order is a 1.5th order component and its higher order component, as shown in FIG. A straight line Lx that approximates the sound pressure level of the fifth-order component,... Is calculated by, for example, the least square method, and the inclination angle (analysis inclination angle) x of this straight line is calculated.

  When the fundamental order is a 3.0th order component and its higher order component, as shown in FIG. 6B, the peak level inclination angle is 3.0th order component, 6.0th order component, 9. A straight line Lx that approximates the sound pressure level of the zeroth order component,... Is calculated by, for example, the least square method, and the inclination angle x (analysis inclination angle) of this straight line is calculated.

  The order to be analyzed is, for example, up to the twentieth component. That is, this S206 is used as an analytical tilt angle calculation means.

  In step S207, the ideal inclination angle xr corresponding to the fundamental tone order is read. The ideal tilt angle xr is recorded in the HD built in the computer main body 2 as described above. Therefore, the HD built in the computer main body 2 is provided as an ideal tilt angle storage means. .

  Next, in S208, the total value of the sound pressure levels of the background noise existing between the respective orders of multiples of the 0.5th order component (the total value of the 0.5th order pitch background noise) NL0.5 is calculated. . As shown in FIG. 4, the 0.5th order pitch background noise is a portion excluding the main order component of the 0.5th order component (0.0th to 0.4th order component, 0.6th to 0.9th order). The sound pressure level of the component, 1.1 to 1.4 order component,. In the present embodiment, the 0.5th-order pitch background noise is extracted and added, but as the total value of the sound pressure level of the background noise, there are other primary pitches, secondary pitches, or other values. May be extracted and the sound pressure level of the background noise may be added.

  Next, proceeding to S209, the sum of these sound pressure levels, that is, the main order level sum value S is calculated based on the fundamental order and its higher order component level.

Next, the process proceeds to S210, and the level of cooperative feeling is calculated and output by the following quantitative feeling evaluation expression, and the routine is exited.
Sense of harmony = -A ・ | xr-x | -B ・ NL0.5 + C ・ S + D
Here, A, B, C, and D are preset constants (positive values in the present embodiment), and the determination range of the sense of harmony level is determined according to how these constants are set, The degree of influence of each operation term is also determined.

  According to the above-mentioned quantitative evaluation formula for the sense of harmony, the sense of harmony level decreases as the analytical tilt angle x deviates greatly from the ideal tilt angle xr by the first calculation term. In other words, this is an arithmetic term indicating that the level of harmony decreases as the distance from the sound that everyone feels as a beautiful sound with a high sense of harmony increases.

  Further, according to the second calculation term, the level of cooperating feeling decreases as the total value NL0.5 of the 0.5th order pitch background noise increases. In other words, this is an arithmetic term indicating that the greater the total value NL0.5 of the 0.5th-order pitch background noise is, the lower the recognizability of the main order component and the lower the sense of harmony.

Further, the third calculation term is such that the level of cooperating feeling increases as the main order level sum value S increases. That is, the larger the major order level sum value S is, the higher the recognizability of the major order component is, and the calculation term indicates that the sense of coexistence increases.
Thus, S210 serves as a quantitative evaluation means.

  Thereafter, returning to FIG. 2 again, the process proceeds to S105, and the evaluation value of the evaluation sound is calculated. For example, as shown in FIG. 7, the evaluation value of the evaluation sound is an evaluation value focusing only on the total value of the sense of unity in the region of the engine speed NEC1 to NEC2. Of course, the evaluation value may be all engine speed ranges.

  Next, the process proceeds to S106, and the evaluation result of the evaluation sound is displayed. Specifically, as shown in FIG. 8, for example, the sound pressure level is three-dimensionally displayed with the engine speed and the frequency, and the sound quality is displayed. Then, along with this display, what percentage of the preset judgment value is ((evaluation value / judgment value) · 100) is displayed as the evaluation result.

  Then, the process proceeds to S107 to determine whether or not the above-described evaluation result has achieved the target. For example, when the evaluation result is 90% or more, it is determined that the target has been achieved, and the sound quality evaluation is terminated. Conversely, if the evaluation result is less than 90%, it is determined that the target has not been achieved, and the process proceeds to S108, and sensitivity analysis is performed on the evaluation value of each order component and frequency band component from the sound quality displayed in S106. . For example, it is analyzed whether there is a specific order component that has a large influence on the evaluation result, or a specific frequency band component that has a large influence on the evaluation result.

  Next, the process proceeds to S109, and a design variable is selected (change of a specific order component or a specific frequency band component) based on the analysis result in S108.

  In S110, the target achievement sound quality is calculated when the design change selected in S109 is executed, and the processing from S104 is repeated again.

  As described above, according to the embodiment of the present invention, the measured evaluation sound to be evaluated is subjected to order analysis, and the slope of a straight line with respect to the sound pressure level of the order component which is the fundamental sound of the evaluation sound subjected to the order analysis and its overtone component is obtained. Calculated as an analytical inclination angle x, the difference between the analytical inclination angle x and the ideal inclination angle xr stored in advance, and the total value NL0.5 of the 0.5th-order pitch background noise determined as the total value of background noise Thus, the sense of unity level is obtained from the unity sense quantitative evaluation formula formed including the calculation terms for each of the main order level summation values S. For this reason, it is possible to perform appropriate quantitative evaluation with reproducibility for a sense of harmony regarding various sounds generated in the vehicle.

  In the present embodiment, the sound evaluation related to the four-cylinder engine and the six-cylinder engine vehicle has been described. However, a program for evaluating only the four-cylinder engine vehicle or the six-cylinder engine vehicle may be used. In addition, the evaluation of the sound related to the vehicle of the engine having the number of cylinders other than these may be performed in the same manner. In addition, the Kyowakan quantitative evaluation formula is the sum of the difference between the analysis inclination angle x and the ideal inclination angle xr stored in advance and the 0.5th-order pitch background noise obtained as the total value of the sound pressure level of the background noise. Although the calculation terms for each of the value NL0.5 and the main order level total value S are formed, the difference between the analysis inclination angle x and the ideal inclination angle xr stored in advance and the background noise It may be formed including a calculation term for only the total value NL0.5 of the 0.5th order pitch background noise obtained as the total value of the sound pressure level, or the analysis inclination angle x and the ideal inclination stored in advance. You may form including the calculation term about only the difference with angle xr, and main order level total value S.

The block diagram which shows the whole sound quality evaluation apparatus for vehicles Flow chart of sound quality evaluation program Flowchart of the calculation processing routine for the level of cooperativeness using the quantitative evaluation formula for cooperativeness Explanatory drawing showing an example of order analysis of evaluation sound Explanatory drawing which shows an example of the analysis of the interior sound of a 4-cylinder engine Explanatory drawing showing an example of analysis of in-vehicle sound of 6-cylinder engine Illustration of evaluation of evaluation sound Illustration of an example of displaying sound quality with engine speed and frequency

Explanation of symbols

1 Personal Computer 2 Computer Body 3 Keyboard 4 Mouse 5 Monitor

Claims (8)

Order analysis means for order analysis of the measured evaluation sound to be evaluated;
Ideal inclination angle storage means for storing an ideal inclination angle of a straight line with respect to the sound pressure level of the order component serving as a fundamental tone and the harmonic component serving as a harmonic thereof, as an ideal inclination angle;
An analysis inclination angle calculation means for obtaining an inclination of a straight line with respect to the sound pressure level of the order component serving as the fundamental tone and the harmonic order component of the evaluation sound subjected to the order analysis as an analysis tilt angle;
A quantitative evaluation means for presetting an evaluation formula for quantitatively evaluating the sense of harmony of the evaluation sound based on at least the ideal tilt angle and the analysis tilt angle, and quantitatively evaluating the sense of harmony of the evaluation sound based on the evaluation formula; ,
A vehicle sound quality evaluation apparatus comprising:   The evaluation formula includes an operation term that varies an evaluation result of the evaluation formula in accordance with a total of sound pressure levels of background noise existing between multiple orders of multiples of a predetermined number order component. The vehicle sound quality evaluation apparatus according to claim 1.   The said evaluation formula has an operation term which changes the evaluation result of the said evaluation formula according to the sum total of the sound pressure level of the order component used as the said fundamental sound, and the order component used as its harmonic. Item 3. The vehicle sound quality evaluation apparatus according to Item 2.   2. A determination unit according to claim 1, further comprising: a determination unit that determines that the evaluation sound achieves a target when a result of the quantitative evaluation unit is equal to or greater than a predetermined determination value in a predetermined engine speed range. The vehicle sound quality evaluation apparatus according to any one of 3.   5. The vehicle sound quality evaluation apparatus according to claim 1, wherein the evaluation sound is an evaluation sound of a vehicle of either a 4-cylinder engine or a 6-cylinder engine.   6. The vehicle sound quality evaluation apparatus according to claim 5, wherein when the evaluation sound is an evaluation sound of a vehicle having a four-cylinder engine, the order of the fundamental sound is a 2.0th-order component.   When the evaluation sound is an evaluation sound of a 6-cylinder engine vehicle, the sound pressure level of the 1.5th order component is compared with the sound pressure level of the 1.5th order component and the 6.0th order component. When the sound pressure level is higher than the sound pressure level of the second component, the harmonic component is a 1.5th harmonic component, and when the sound pressure level of the 6.0th component is higher than the sound pressure level of the 1.5th component, 6. The vehicle sound quality evaluation apparatus according to claim 5, wherein the harmonic component is a 3.0th-order harmonic component. An order analysis step for order analysis of the measured evaluation sound to be evaluated;
An analysis inclination angle calculation step for obtaining an inclination angle of a straight line with respect to the sound pressure level of the order component that is the fundamental sound of the evaluation sound and the harmonic component that is the harmonic order, as an analysis inclination angle;
An evaluation formula is set in advance to quantitatively evaluate the sense of unity of the evaluation sound based on the ideal ideal inclination angle of the straight line with respect to the sound pressure level of the order component which is the fundamental tone and the harmonic order component and the analysis inclination angle. A quantitative evaluation step for quantitatively evaluating the sense of harmony of the evaluation sound based on the evaluation formula;
A sound quality evaluation method for a vehicle, comprising:

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