Vehicle acceleration dynamic response consistency evaluation method based on time domain response characteristics

Abstract

The application is suitable for the technical field of automobile performance evaluation, and provides a vehicle acceleration dynamic response consistency evaluation method based on time domain response characteristics, which comprises the following steps: step 1, test condition definition; step 2, data acquisition and preprocessing; and step 3, evaluation index calculation. The method is composed of three parts of test condition definition, data acquisition and preprocessing and evaluation index calculation, can objectively and accurately quantify the vehicle acceleration dynamic response consistency, effectively makes up for the lack of evaluation method in the prior art and the difficulty in realizing objective quantification, and provides reliable technical support for vehicle performance optimization and driving quality improvement.

Description

Technical Field

[0001] This invention belongs to the field of automotive performance evaluation technology, and in particular relates to a method for evaluating the consistency of vehicle acceleration dynamic response based on time-domain response characteristics. Background Technology

[0002] With the continuous development of the automotive industry and the increasing diversity of vehicle products, drivers are paying more and more attention to vehicle drivability. The dynamic response characteristics of a vehicle during acceleration directly affect drivability, and consistent dynamic response characteristics help create a stable driving experience, reduce driver workload, and avoid misoperation and safety risks caused by inconsistent responses. Currently, the industry lacks a systematic and quantitative evaluation method for the consistency of acceleration dynamic response, making it difficult to scientifically assess this performance. Therefore, establishing an accurate and objective evaluation method for vehicle acceleration dynamic response consistency is of great significance for supporting the development and optimization of vehicle acceleration dynamic response consistency control.

[0003] Chinese invention patent CN119218234A, entitled "Driving Performance Evaluation Method, System, Electronic Device and Storage Medium for Vehicles," objectively evaluates the acceleration performance of heavy-duty vehicles with automatic mechanical transmissions (AMT) by calculating multiple indicators such as longitudinal acceleration disturbance characteristics, frequency distribution, acceleration gradient, desired acceleration, throttle matching degree, and low-frequency resonance under constant acceleration conditions, and combining them with preset weights to generate a comprehensive driving performance score. However, this method mainly focuses on the comprehensive performance level evaluation under constant acceleration conditions and does not consider the temporal consistency characteristics of the acceleration dynamic response process, thus making it difficult to quantitatively describe the consistency of acceleration dynamic response under different operating conditions.

[0004] Chinese invention patent CN108072530A, entitled "An Evaluation Method for Automobile Driving Performance," sets four standardized pedal operation conditions—gentle pressing, sharp pressing, gentle releasing, and sharp releasing—and collects the vehicle's longitudinal acceleration curves under specific gear and engine speed conditions. It then quantitatively evaluates driving performance based on the first peak value of the acceleration curve (used to evaluate impact) and the peak stabilization time (used to evaluate smoothness). However, this method only analyzes the acceleration curve characteristics under specific operating conditions, failing to comprehensively consider the impact of load changes and road slope variations on the vehicle's acceleration response process, and also lacks an evaluation mechanism for the consistency of dynamic acceleration response. Summary of the Invention

[0005] The purpose of this invention is to provide a method for evaluating the consistency of vehicle acceleration dynamic response based on time-domain response characteristics, aiming to solve the problems mentioned in the background art.

[0006] The present invention is implemented as follows: a vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics includes the following steps:

[0007] Step 1: Define test conditions;

[0008] The working conditions of the quantitative test include key information such as vehicle speed, vehicle load status, road slope, accelerator pedal opening and driver operation mode, to determine the working condition parameters for the acceleration dynamic response consistency test.

[0009] Step 2: Data Acquisition and Preprocessing;

[0010] Determine the characteristic physical quantities and sampling frequency to be collected to ensure that the collected data meets the needs of subsequent evaluation index calculation and analysis; perform outlier removal, low-pass filtering and filter delay correction on the collected data to eliminate noise and compensate for the time delay introduced by filtering.

[0011] Step 3: Calculate the evaluation indicators;

[0012] Define the root mean square error of peak acceleration. Root mean square error of peak acceleration response time Root mean square error of dynamic response Three evaluation indicators; each indicator is calculated based on the preprocessed data to objectively and quantitatively evaluate the consistency of the vehicle's dynamic acceleration response.

[0013] In a further technical solution, in step 1, the test condition is defined as the vehicle starting from a standstill, with the driver depressing the accelerator pedal at a constant rate, the pedal opening rate being controlled at 15% per second, and the same rate being used to actuate the accelerator pedal in each test.

[0014] Stable pedal openings of 10%, 30%, and 50% were selected as typical acceleration conditions. The vehicle was accelerated at each pedal opening. The test ended after the vehicle acceleration reached its maximum and showed a clear downward trend.

[0015] A further technical solution involves conducting combined working condition tests at each pedal opening degree under no-load, half-load, and full-load conditions, combined with road slopes of 0%, 8%, and 15%, to form a total of 9 typical working conditions for subsequent evaluation of the consistency of acceleration dynamic response.

[0016] In a further technical solution, step 2 includes the following specific steps:

[0017] Tests were conducted on three accelerator pedal openings and nine typical operating conditions under each pedal opening. Simultaneously, the accelerator pedal trigger signal, accelerator pedal opening signal, and vehicle acceleration time-domain signal were collected. The accelerator pedal trigger signal was used for time alignment, the accelerator pedal opening signal was used to confirm whether the pedal opening met the test requirements, and the acceleration signal was used for data processing and index calculation. The sampling frequency was 100 Hz.

[0018] A one-dimensional median filtering method is used to smooth the vehicle acceleration signal and remove anomalies; the specific processing method is as follows: Let the original time-domain signal be... The filter window length is ; at each sampling time Retrieve the sequence within the window for:

[0019] ;

[0020] In the formula, This represents the number of sampling points on either side of the center point of the median filter window;

[0021] For sequence Sort the data in ascending order and take the median as the output:

[0022] ;

[0023] In the formula, For the processed time-domain data, For sequence of the median.

[0024] Thus, we obtain the accelerator pedal opening signal and the vehicle acceleration signal after outlier removal.

[0025] The vehicle acceleration signal after median filtering is processed by an FIR low-pass filter with a cutoff frequency of 5 Hz, and the time lag introduced by the filtering is corrected by zero-phase bidirectional filtering to remove high-frequency noise and maintain signal time alignment.

[0026] A further technical solution is that, in step 3, the root mean square error of the peak acceleration... Evaluate the magnitude of the deviation of peak acceleration from the unloaded flat road condition for each working condition to the unloaded flat road condition, and the root mean square error of the peak acceleration response time. Evaluate the magnitude of the deviation between the peak acceleration response time and the unloaded flat road condition for each working condition, and the root mean square error of the dynamic response. Evaluate the magnitude of the cumulative deviation between the acceleration time-domain curves of each working condition on a non-unloaded flat road and the working condition on an unloaded flat road;

[0027] Before calculating the evaluation index, the preprocessed data is classified according to the accelerator pedal opening signal, and the data is divided into datasets corresponding to the three pedal openings of 10%, 30% and 50%.

[0028] Starting from the trigger moment of the accelerator pedal trigger signal, the acceleration time-domain curves under different operating conditions at each pedal opening are aligned, and various indicators are calculated according to the evaluation index calculation formula, as follows:

[0029] ;

[0030] In the formula, For the number of test conditions, The peak acceleration under unloaded flat road conditions. This represents the peak acceleration under the combined load and slope conditions. The peak acceleration response time under no-load flat road conditions. For the remaining load and slope combination conditions, the peak acceleration response time is... This is the cumulative value of the acceleration deviation between the non-unloaded flat road conditions and the unloaded flat road conditions.

[0031] The calculation formula is as follows:

[0032] ;

[0033] In the formula, The acceleration time-domain curves for various operating conditions on a non-unloaded flat road are shown. The acceleration time-domain curve is shown for unloaded flat road conditions. For time;

[0034] according to , and The three evaluation indicators are used to assess the consistency of the dynamic acceleration response at each accelerator pedal opening.

[0035] The vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics provided in this invention consists of three parts: test condition definition, data acquisition and preprocessing, and evaluation index calculation. It can objectively and accurately quantify the consistency of vehicle acceleration dynamic response, effectively making up for the lack of evaluation methods and the difficulty in achieving objective quantification in the prior art, and providing reliable technical support for vehicle performance optimization and driving quality improvement. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics provided in an embodiment of the present invention.

[0037] Figure 2 A schematic diagram of the consistency evaluation index for acceleration dynamic response. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0040] like Figure 1 As shown, a vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics is provided in an embodiment of the present invention, including the following steps:

[0041] Step 1: Define test conditions;

[0042] The working conditions of the quantitative test include key information such as vehicle speed, vehicle load status, road slope, accelerator pedal opening and driver operation mode, to determine the working condition parameters for the acceleration dynamic response consistency test.

[0043] The test condition is defined as starting the vehicle from a standstill, with the driver pressing the accelerator pedal at a constant rate. The rate of change of the pedal opening is controlled at 15% per second, and the same rate of actuation of the accelerator pedal is used in each test.

[0044] Considering that emergency acceleration conditions are rare in actual driving, this method selects stable pedal openings of 10%, 30%, and 50% as typical acceleration conditions, and accelerates the vehicle at each pedal opening. The test ends when the vehicle acceleration reaches its maximum and shows a clear downward trend.

[0045] At each pedal opening, combined working condition tests were conducted under no-load, half-load, and full-load conditions, including flat road (0% slope), small slope (8% slope), and large slope (15% slope), to form a total of 9 typical working conditions for subsequent evaluation of the consistency of acceleration dynamic response.

[0046] Step 2: Data Acquisition and Preprocessing;

[0047] Based on the test conditions defined in step 1, determine the characteristic physical quantities and sampling frequency to be collected to ensure that the collected data can meet the needs of subsequent evaluation index calculation and analysis; perform outlier removal, low-pass filtering and filter delay correction on the collected data to eliminate the influence of noise and compensate for the time delay introduced by filtering, thereby ensuring the accuracy of evaluation index calculation.

[0048] Specifically, tests were conducted on three accelerator pedal openings and nine typical operating conditions under each pedal opening. Simultaneously, the accelerator pedal trigger signal, accelerator pedal opening signal, and vehicle acceleration time-domain signal were collected. The accelerator pedal trigger signal was used for time alignment, the accelerator pedal opening signal was used to confirm whether the pedal opening met the test requirements, and the acceleration signal was used for data processing and index calculation. The sampling frequency was 100 Hz.

[0049] A one-dimensional median filtering method is used to smooth the vehicle acceleration signal and remove outliers. The specific processing method is as follows: Let the original time-domain signal be... The filter window length is ; at each sampling time Retrieve the sequence within the window for:

[0050] ;

[0051] In the formula, This represents the number of sampling points on both sides of the center point of the median filter window.

[0052] For sequence Sort the data in ascending order and take the median as the output:

[0053] ;

[0054] In the formula, For the processed time-domain data, For sequence of the median.

[0055] Thus, the accelerator pedal opening signal and vehicle acceleration signal, after outlier removal processing, are obtained.

[0056] The vehicle acceleration signal after median filtering is processed by an FIR low-pass filter with a cutoff frequency of 5 Hz, and the time lag introduced by the filtering is corrected by zero-phase bidirectional filtering in order to remove high-frequency noise and maintain signal time alignment.

[0057] Step 3: Calculate the evaluation indicators;

[0058] There are three evaluation metrics for the consistency of acceleration dynamic response: peak root mean square error of acceleration. Root mean square error of peak acceleration response time and root mean square error of dynamic response ; where the root mean square error of the peak acceleration Evaluate the magnitude of the deviation of peak acceleration from the unloaded flat road condition for each working condition to the unloaded flat road condition, and the root mean square error of the peak acceleration response time. Evaluate the magnitude of the deviation between the peak acceleration response time and the unloaded flat road condition for each working condition, and the root mean square error of the dynamic response. The cumulative deviation of the acceleration time-domain curves for each working condition on a non-unloaded flat road compared to the unloaded flat road working condition is evaluated, and the indicators are illustrated as follows: Figure 2 As shown.

[0059] Before calculating the evaluation index, the preprocessed data is classified according to the accelerator pedal opening signal, and the data is divided into datasets corresponding to the three pedal openings of 10%, 30% and 50%.

[0060] Starting from the trigger moment of the accelerator pedal trigger signal, the acceleration time-domain curves under different operating conditions at each pedal opening are aligned, and various indicators are calculated according to the evaluation index calculation formula, as follows:

[0061] ;

[0062] In the formula, For the number of test conditions, The peak acceleration under unloaded flat road conditions. This represents the peak acceleration under the combined load and slope conditions. The peak acceleration response time under no-load flat road conditions. For the remaining load and slope combination conditions, the peak acceleration response time is... This is the cumulative value of the acceleration deviation between the non-unloaded flat road conditions and the unloaded flat road conditions.

[0063] The calculation formula is as follows:

[0064] ;

[0065] In the formula, The acceleration time-domain curves for various operating conditions on a non-unloaded flat road are shown. The acceleration time-domain curve is shown for unloaded flat road conditions. For time.

[0066] according to , and The three evaluation indicators are used to assess the consistency of the dynamic acceleration response at each accelerator pedal opening.

[0067] This method was used to verify the performance of vehicle models employing two different control strategies. The results of the evaluation index calculation are shown in Table 1 below:

[0068] Table 1 Objective Evaluation Index Values

[0069]

[0070] The test results show that Model 1 exhibits significant dispersion across all three evaluation indicators, indicating poor consistency in its acceleration dynamic response under different operating conditions. In contrast, Model 2 shows significantly less dispersion across the three indicators, maintaining a more stable acceleration dynamic response under various operating conditions. Based on these test observations, it can be concluded that this method can clearly distinguish the consistency level of dynamic response of vehicles with different control strategies, effectively and accurately reflecting the quality of vehicle acceleration dynamic response consistency, and possesses good testing and evaluation capabilities and application value.

[0071] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for evaluating the consistency of vehicle acceleration dynamic response based on time-domain response characteristics, characterized in that, Includes the following steps: Step 1: Define test conditions; The working conditions of the quantitative test, including vehicle speed, vehicle load status, road slope, accelerator pedal opening and driver operation mode, are used to determine the working condition parameters for the acceleration dynamic response consistency test. Step 2: Data Acquisition and Preprocessing; Determine the characteristic physical quantities and sampling frequency to be collected to ensure that the collected data meets the needs of subsequent evaluation index calculation and analysis; perform outlier removal, low-pass filtering and filter delay correction on the collected data to eliminate noise and compensate for the time delay introduced by filtering. Step 3: Calculate the evaluation indicators; Define the root mean square error of peak acceleration. Root mean square error of peak acceleration response time Root mean square error of dynamic response Three evaluation indicators; each indicator is calculated based on the preprocessed data to objectively and quantitatively evaluate the consistency of the vehicle's dynamic acceleration response. In step 3, the root mean square error of the peak acceleration Evaluate the magnitude of the deviation of peak acceleration from the unloaded flat road condition for each working condition to the unloaded flat road condition, and the root mean square error of the peak acceleration response time. Evaluate the magnitude of the deviation between the peak acceleration response time and the unloaded flat road condition for each working condition, and the root mean square error of the dynamic response. Evaluate the magnitude of the cumulative deviation between the acceleration time-domain curves of each working condition on a non-unloaded flat road and the working condition on an unloaded flat road; Before calculating the evaluation index, the preprocessed data is classified according to the accelerator pedal opening signal, and the data is divided into datasets corresponding to the three pedal openings of 10%, 30% and 50%. Starting from the trigger moment of the accelerator pedal trigger signal, the acceleration time-domain curves under different operating conditions at each pedal opening are aligned, and various indicators are calculated according to the evaluation index calculation formula, as follows: ； In the formula, For the number of test conditions, This represents the peak acceleration under unloaded, flat road conditions. This represents the peak acceleration under the combined load and slope conditions. The peak acceleration response time under no-load flat road conditions. For the remaining load and slope combination conditions, the peak acceleration response time is... This is the cumulative value of the acceleration deviation between the non-unloaded flat road conditions and the unloaded flat road conditions. The calculation formula is as follows: ； In the formula, The acceleration time-domain curves for various operating conditions on a non-unloaded flat road are shown. The acceleration time-domain curve is shown for unloaded flat road conditions. For time; according to , and The three evaluation indicators are used to assess the consistency of the dynamic acceleration response at each accelerator pedal opening.

2. The vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics according to claim 1, characterized in that, In step 1, the test condition is defined as the vehicle starting from a standstill, with the driver depressing the accelerator pedal at a constant rate, the rate of change of the pedal opening being controlled at 15% per second, and the same rate of actuation of the accelerator pedal being used in each test. Stable pedal openings of 10%, 30%, and 50% were selected as typical acceleration conditions. The vehicle was accelerated at each pedal opening. The test ended after the vehicle acceleration reached its maximum and showed a clear downward trend.

3. The vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics according to claim 2, characterized in that, In step 1, at each pedal opening, combined working condition tests were conducted under no-load, half-load, and full-load conditions, along with road slopes of 0%, 8%, and 15%, to form a total of 9 typical working conditions for subsequent evaluation of the consistency of acceleration dynamic response.

4. The vehicle acceleration dynamic response consistency evaluation method based on time-domain response characteristics according to claim 3, characterized in that, Step 2 includes the following specific steps: Tests were conducted on three accelerator pedal openings and nine typical operating conditions under each pedal opening. Simultaneously, the accelerator pedal trigger signal, accelerator pedal opening signal, and vehicle acceleration time-domain signal were collected. The accelerator pedal trigger signal was used for time alignment, the accelerator pedal opening signal was used to confirm whether the pedal opening met the test requirements, and the acceleration signal was used for data processing and index calculation. The sampling frequency was 100 Hz. A one-dimensional median filtering method is used to smooth the vehicle acceleration signal and remove anomalies; the specific processing method is as follows: Let the original time-domain signal be... The filter window length is ; at each sampling time Retrieve the sequence within the window for: ； In the formula, This represents the number of sampling points on either side of the center point of the median filter window; For sequence Sort the data in ascending order and take the median as the output: ； In the formula, For the processed time-domain data, For sequence the median; Thus, we obtain the accelerator pedal opening signal and the vehicle acceleration signal after outlier removal. The vehicle acceleration signal after median filtering is processed by an FIR low-pass filter with a cutoff frequency of 5 Hz, and the time lag introduced by the filtering is corrected by zero-phase bidirectional filtering to remove high-frequency noise and maintain signal time alignment.

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