A method for evaluating acceleration smoothness of an automobile

Abstract

The application provides a kind of automobile acceleration smoothness evaluation method, it includes the following steps: step S1, obtains the data of acceleration value and time in automobile driving process;Step S2, the jerk value corresponding to each data point is calculated to determine the acceleration inflection point;Step S3, the acceleration inflection point meeting the requirement is screened out;Step S4, the absolute value of the jerk value in a certain range before and after each acceleration inflection point screened out is used to calculate the jerk coefficient of each acceleration inflection point, to evaluate the acceleration smoothness of automobile at each acceleration inflection point;The maximum value and average value of each jerk coefficient are used to evaluate the acceleration smoothness of automobile.The maximum value and average value of the jerk coefficient of each acceleration inflection point obtained by the application can evaluate the smoothness of automobile, realize the evaluation of automobile smoothness by quantitative index, so as to better provide data support for product performance optimization.

Description

Technical Field

[0001] This invention belongs to the field of vehicle ride comfort evaluation technology, and specifically relates to a method for evaluating vehicle acceleration ride comfort. Background Technology

[0002] The smoothness of a vehicle's ride significantly impacts the driving and passenger experience, reflecting the vehicle's comfort level. During vehicle development, numerous driving experience tests and evaluation experiments are required, with overall vehicle smoothness being a crucial testing component used to assess overall vehicle comfort. Accurate, reasonable, and quantitative evaluation of vehicle smoothness is beneficial for setting, optimizing, verifying, and achieving design goals during the vehicle development process.

[0003] Currently, the industry primarily uses subjective evaluation methods to assess vehicle ride comfort. These methods involve subjective evaluation engineers driving the vehicle under specific conditions for a period of time and then scoring its ride comfort based on their memory of the experience. A 10-point scale is used, with 6 points indicating acceptable comfort and higher scores signifying better ride comfort. However, this subjective evaluation method, while reflecting the overall performance of the product, cannot quantify the impact of individual performance optimizations on ride comfort, thus offering limited support for product performance optimization efforts. Therefore, how to evaluate vehicle ride comfort using quantitative indicators to improve support for product performance optimization has become a pressing technical problem for those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a method for evaluating the smoothness of vehicle acceleration, so as to solve the above-mentioned technical problems in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for evaluating the smoothness of vehicle acceleration includes the following steps:

[0007] Step S1: Obtain data on acceleration values ​​and time during the vehicle's movement;

[0008] Step S2: Calculate the acceleration value corresponding to each data point to determine the acceleration inflection point;

[0009] Step S3: Select acceleration inflection points that meet the requirements;

[0010] Step S4: Calculate the jerk coefficient of each acceleration inflection point by using the absolute values ​​of acceleration values ​​within a certain range before and after each selected acceleration inflection point to evaluate the acceleration smoothness of the car at each acceleration inflection point; use the maximum and average values ​​of each jerk coefficient to evaluate the acceleration smoothness of the car.

[0011] Preferably, in step S1, the acceleration value is obtained from the vehicle speed.

[0012] Preferably, in step S1, the acceleration value is obtained by an accelerometer installed on the vehicle.

[0013] Preferably, the accelerometer is a gyroscope.

[0014] Preferably, in step S2, the acceleration value is obtained by calculating the derivative of acceleration with respect to time.

[0015] Preferably, in step S2, the rule for determining the acceleration inflection point is that the acceleration value of the data point preceding the acceleration inflection point and the acceleration value of the data point following the acceleration inflection point have opposite signs.

[0016] Preferably, in step S3, the selected acceleration inflection points must meet the following requirements: the interval between two adjacent acceleration inflection points is a certain time, and within a set time before and after the acceleration inflection point or within a set number of data points, the absolute value of the acceleration value of at least one data point is greater than a set value.

[0017] Preferably, the time interval between two adjacent acceleration inflection points is 0.3s to 0.7s.

[0018] Preferably, the set value is 3 m / s 3 Up to 5m / s 3 The set time is 0.6 seconds; the set quantity is three.

[0019] Preferably, in step S4, the method for calculating the jerk coefficient is as follows: extract the maximum absolute value of the acceleration values ​​of the two data points before the acceleration inflection point and the maximum absolute value of the acceleration values ​​of the two data points after the acceleration inflection point, and the average of the two maximum values ​​is the jerk coefficient of the acceleration inflection point.

[0020] The beneficial effects of this invention are as follows:

[0021] The vehicle acceleration smoothness evaluation method of the present invention evaluates the smoothness of the vehicle by using the maximum and average values ​​of the jerking coefficients at each acceleration inflection point. This method achieves the evaluation of vehicle smoothness through quantitative indicators, thereby providing better data support for product performance optimization. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly described below, and the specific embodiments of the present invention will be further described in detail with reference to the drawings, wherein...

[0023] Figure 1 A flowchart illustrating the vehicle acceleration smoothness evaluation method provided in this embodiment of the invention;

[0024] Figure 2 This is a schematic diagram of the acceleration inflection point provided in an embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solution of the present invention, the present solution will be further described in detail below with reference to specific embodiments.

[0026] like Figure 1 As shown in the figure, this invention provides a method for evaluating the smoothness of vehicle acceleration, which includes the following steps:

[0027] Step S1: Obtain data on acceleration values ​​and time during the vehicle's movement;

[0028] Step S2: Calculate the acceleration value corresponding to each data point to determine the acceleration inflection point;

[0029] Step S3: Select acceleration inflection points that meet the requirements;

[0030] Step S4: Calculate the jerk coefficient of each acceleration inflection point by using the absolute values ​​of acceleration values ​​within a certain range before and after each selected acceleration inflection point to evaluate the acceleration smoothness of the car at each acceleration inflection point; use the maximum and average values ​​of each jerk coefficient to evaluate the acceleration smoothness of the car.

[0031] Understandably, the jerk coefficient is used to evaluate the smoothness of a car. The larger the jerk coefficient, the worse the smoothness of the car at that acceleration inflection point; the smaller the jerk coefficient, the better the smoothness of the car at that acceleration inflection point. In the evaluation, if the maximum and average values ​​of the jerk coefficients at each acceleration inflection point are both less than the set values, then the overall acceleration smoothness of the car is good; otherwise, the car's smoothness is poor. Of course, the maximum or average value of the jerk coefficients at each acceleration inflection point can also be used as an evaluation index, but this cannot comprehensively evaluate the acceleration smoothness.

[0032] For automakers, a comparative approach is preferable for evaluating vehicle smoothness. This involves two main methods: first, comparing with competitors and benchmark vehicles; and second, comparing the jerking coefficients at different stages of the development process, before and after smoothness improvement efforts. This comparison serves to evaluate vehicle smoothness and the effectiveness of related controls and optimizations. For example, if the maximum value of the jerking coefficient at each acceleration inflection point of a vehicle is less than that of competing vehicles, and the average value of the jerking coefficient at each acceleration inflection point of the vehicle is also less than the average value of the jerking coefficient at each acceleration inflection point of the competing vehicles, then the vehicle's acceleration smoothness is better than that of the competing vehicles. Conversely, if the maximum value of the jerking coefficient of the vehicle is greater than that of competing vehicles, then optimization can be performed at the acceleration inflection point corresponding to the maximum value of the jerking coefficient.

[0033] Vehicle driving conditions can be summarized into four driving states: stopping, acceleration, constant speed, and deceleration. Currently, automobiles on the market generally do not have smoothness issues in stopping, constant speed, and deceleration conditions. Therefore, this invention is aimed at acceleration conditions where smoothness issues often occur, but it is also applicable to constant speed and deceleration conditions.

[0034] The vehicle acceleration smoothness evaluation method provided in this invention evaluates vehicle smoothness by using the maximum and average values ​​of the jerking coefficients at each acceleration inflection point. This method achieves vehicle smoothness evaluation through quantitative indicators, thereby providing better data support for product performance optimization and providing direction for optimization.

[0035] Furthermore, in step S1, the acceleration value is obtained from the vehicle speed. It can be understood that the acceleration value can be obtained by differentiating the vehicle speed from time.

[0036] In another embodiment, in step S1, the acceleration value is obtained by an accelerometer installed on the vehicle.

[0037] Ideally, the accelerometer should be a gyroscope.

[0038] Specifically, in step S2, the acceleration value is obtained by calculating the derivative of acceleration with respect to time.

[0039] Furthermore, in step S2, the rule for determining the acceleration inflection point is: the acceleration value of the data point preceding the acceleration inflection point and the acceleration value of the data point following the acceleration inflection point have opposite signs, that is, one is a positive value and the other is a negative value.

[0040] Furthermore, in step S3, the selected acceleration inflection points must meet the following requirements: the interval between two adjacent acceleration inflection points is a certain time, and within a set time period before and after the acceleration inflection point or within a set number of data points, the absolute value of the acceleration value of at least one data point is greater than the set value.

[0041] Specifically, the interval between two adjacent acceleration inflection points is 0.3s to 0.7s, preferably 0.5s, meaning the interval between two adjacent acceleration inflection points must be greater than 0.5s. It is understandable that setting this interval effectively avoids using the same data points when calculating the jerk coefficient, thus preventing duplicate evaluations. This time value can be obtained through statistical analysis using 10Hz data, based on a large amount of experimental data combined with subjective evaluations.

[0042] The preferred value is 3 m / s. 3 Up to 5m / s 3 The optimal value is 4 m / s. 3 This value can be obtained statistically from subjective evaluation combined with experimental data; the set time is 0.6s; the set number is three. In this embodiment, the selected acceleration inflection point must meet the following condition: within 0.6s before and after the acceleration inflection point, or within the range of three data points, the absolute value of the acceleration value of at least one data point is greater than 4m / s². 3 .

[0043] Specifically, in step S4, the abruptness coefficient is calculated as follows: The maximum absolute value of the acceleration values ​​at the two data points before the acceleration inflection point and the maximum absolute value of the acceleration values ​​at the two data points after the acceleration inflection point are extracted. The average of these two maximum values ​​is the abruptness coefficient for that acceleration inflection point. It can be understood that the maximum absolute value of the acceleration values ​​at the two data points before the acceleration inflection point can be denoted as a. max The maximum absolute value of the acceleration values ​​of the two data points after the acceleration inflection point can be denoted as b. max When extracting the maximum value, it is not limited to using only two data points before and after the acceleration inflection point. Three or more data points before and after the acceleration inflection point can be used, and the specific number of data points can be flexibly set.

[0044] It is understandable that the acceleration value obtained during the car's movement can be in the direction of the car's movement (which can be defined as the X direction), the lateral direction of the car body (which can be defined as the Y direction), or the direction perpendicular to the ground (which can be defined as the Z direction).

[0045] like Figure 2 As shown in Table 1, a specific embodiment is provided, taking the vehicle's driving direction (X direction) as an example, to introduce the process of obtaining the jerking coefficient in this direction. The calculation method for other directions (such as Y and Z directions) is the same; in the following specific embodiments, a data frequency of 10Hz is used as an example. Figure 2 The large black dot indicates the inflection point.

[0046] Table 1 Data for specific embodiments

[0047]

[0048]

[0049] The vehicle ride comfort evaluation method of the present invention is applicable to all passenger cars and commercial vehicles, and is applicable to ride comfort evaluation in the X, Y, and Z directions during vehicle operation. In addition, the evaluation method is also applicable to ride comfort evaluation under constant speed and deceleration conditions.

[0050] This invention provides a reasonable and accurate method for evaluating vehicle ride comfort. The evaluation algorithm is based on quantitative data, identifies typical characteristics of jerking sensation during vehicle driving, establishes an evaluation feature parameter algorithm, and evaluates the ride comfort through quantitative parameters.

[0051] The evaluation results described in this invention are intuitive and can clearly reflect the optimization effect of the test vehicle's ride comfort, as well as the gap with competing and benchmark vehicles in the market.

[0052] The above are merely preferred embodiments of the present invention. It should be noted that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. Moreover, after reading the contents of the present invention, those skilled in the art can make various modifications or alterations to the present invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A method for evaluating acceleration smoothness of an automobile, characterized by comprising: It includes the following steps: Step S1: Obtain data on acceleration values ​​and time during the vehicle's movement; Step S2: Calculate the acceleration value corresponding to each data point to determine the acceleration inflection point; Step S3: Select acceleration inflection points that meet the requirements; Step S4: Calculate the jerking coefficient of each acceleration inflection point by using the absolute values ​​of acceleration values ​​within a certain range before and after each selected acceleration inflection point, in order to evaluate the acceleration smoothness of the car at each acceleration inflection point. The acceleration smoothness of a car is evaluated by using the maximum and average values ​​of each jerking coefficient. In step S2, the rule for determining the acceleration inflection point is: the acceleration value of the data point preceding the acceleration inflection point and the acceleration value of the data point following the acceleration inflection point have opposite signs; In step S3, the selected acceleration inflection points must meet the following requirements: the interval between two adjacent acceleration inflection points is a certain time, and within a set time before and after the acceleration inflection point or within a set number of data points, the absolute value of the acceleration value of at least one data point is greater than the set value. In step S4, the method for calculating the jerk coefficient is as follows: extract the maximum absolute value of the acceleration values ​​of the two data points before the acceleration inflection point and the maximum absolute value of the acceleration values ​​of the two data points after the acceleration inflection point. The average of these two maximum values ​​is the jerk coefficient of the acceleration inflection point.

2. The automobile acceleration smoothness evaluation method according to claim 1, characterized by In step S1, the acceleration value is obtained from the vehicle speed.

3. The automobile acceleration smoothness evaluation method according to claim 1, characterized by, In step S1, the acceleration value is obtained by using an accelerometer installed on the vehicle.

4. The automobile acceleration smoothness evaluation method according to claim 3, characterized by The accelerometer is a gyroscope.

5. The automobile acceleration smoothness evaluation method according to claim 1, characterized by, In step S2, the acceleration value is obtained by calculating the derivative of acceleration with respect to time.

6. The automobile acceleration smoothness evaluation method according to claim 1, characterized by The time interval between two adjacent acceleration inflection points is 0.3s to 0.7s.

7. The automobile acceleration smoothness evaluation method according to claim 1, characterized by The set value is 3 m / s 3 to 5 m / s 3 ; the set time is 0.6 s; the set number is three.

Images