Vehicle driving control performance test and evaluation method based on actual driving conditions

Abstract

The application discloses a vehicle driving control performance product force test and evaluation method based on actual travel conditions, which comprises power driving performance test, braking performance test and steering stability test. After the power driving performance test, the braking performance test and the steering stability test, corresponding final test results are obtained. Based on the three test results, the overall score of the vehicle driving control performance is calculated, and the vehicle driving control performance is evaluated according to the overall score. The test method is a systematic and reasonable vehicle driving control performance product force test and evaluation method based on actual travel conditions in China, and can intuitively reflect the vehicle driving control performance under the actual travel conditions of Chinese consumers.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle performance testing, in particular to a vehicle driving control performance product force test evaluation method based on actual travel conditions. BACKGROUND

[0002] At present, the automobile consumption group tends to be younger, and the driving control performance becomes the primary concern of young consumers. The vehicle driving control performance refers to the ability of the driver to control the vehicle during dynamic driving. The driving control performance includes power driving performance, braking performance and handling stability, which are embodied in the daily use of the vehicle by the consumer and are the core part of the overall performance of the vehicle.

[0003] At present, the evaluation conditions in the national standard GB / T 12543-2009 for power driving performance only include 0-100km / h and 60km / h-100km / h full throttle acceleration extreme conditions, but these two conditions are rarely seen in daily use of the vehicle, so they are inconsistent with the typical travel scenarios of consumers.

[0004] At present, the test conditions for the braking performance of the vehicle are mostly based on GB 21670-2008, which is an extreme condition in the standard. The test standard is the minimum requirement for vehicle access, and cannot accurately reflect the braking performance of the vehicle under actual travel conditions.

[0005] There are two ways to evaluate the handling stability: subjective evaluation and objective evaluation. The subjective evaluation method is based on the feeling of the person to evaluate, which is more consistent with the actual use of the vehicle by the consumer, but it is greatly affected by the state and environmental factors of the evaluator, and the consistency and accuracy of the evaluation results are difficult to guarantee. The objective evaluation method is based on GB / T 6323-2014, which has a large difference from the actual use of the vehicle, and the evaluation indexes are numerous and difficult to understand, and cannot clearly indicate how each index reflects the handling stability quality characteristics of the vehicle.

[0006] In view of the actual travel conditions in China, it is necessary to provide a performance verification method for the OEM in the development process, and to provide an intuitive selection and purchase reference for the driving control performance of the vehicle for the consumer, and to innovatively propose a vehicle driving control performance product force test and evaluation method based on the actual travel conditions in China. SUMMARY

[0007] The purpose of the present application is to solve the technical defects in the prior art, and to provide a vehicle driving control performance product force test evaluation method based on actual travel conditions, which can realize the performance verification of the OEM in the new product development process, upgrade the driving control performance of the vehicle, and ultimately improve the travel quality of the consumer.

[0008] The technical scheme adopted to achieve the object of the present application is:

[0009] A vehicle driving control performance product force test evaluation method based on actual travel conditions, including power driving performance test, braking performance test and handling stability test, after the power driving performance test, the braking performance test and the handling stability test are respectively carried out, the corresponding test final results are respectively obtained: based on the three test results, the overall score of the vehicle driving control performance is calculated, and the vehicle driving control performance is evaluated according to the overall score of the vehicle driving control performance;

[0010] 1. The method of power driving performance test is as follows:

[0011] It is carried out on a clean, dry and flat test road, and the vehicle is preheated before the test starts;

[0012] 1.1 Medium-speed power driving performance test:

[0013] The vehicle is accelerated from a stationary state to 30km / h at 30% throttle opening, and the following indexes are calculated using the collected test data: the time required for a manual transmission vehicle to accelerate from the start of movement to 30km / h; the time required for an automatic transmission vehicle to accelerate from the start of the acceleration pedal to 30km / h; the time required from the start of the acceleration pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration during the process from the start of the acceleration pedal to the peak longitudinal acceleration; the arithmetic mean of the results of each valid index, which is the final result of the index;

[0014] 1.2 Medium-speed power driving performance test

[0015] The vehicle is accelerated from a stationary state to 30km / h at 30% throttle opening, and the following indexes are calculated using the collected test data: the time required for a manual transmission vehicle to accelerate from the start of movement to 30km / h; the time required for an automatic transmission vehicle to accelerate from the start of the acceleration pedal to 30km / h; the time required from the start of the acceleration pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration during the process from the start of the acceleration pedal to the peak longitudinal acceleration; the arithmetic mean of the results of each valid index, which is the final result of the index;

[0016] The time required from the start of the acceleration pedal to 80km / h; the time required from the start of the acceleration pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration during the process from the start of the acceleration pedal to the peak longitudinal acceleration; the arithmetic mean of the results of each valid index, which is the final result of the index;

[0017] 1.3 High-speed power driving performance test

[0018] The vehicle is driven at a constant speed of no less than 110 km / h, the accelerator pedal is released, the vehicle is coasted to 100 ± 1 km / h, the accelerator pedal is depressed to 100% opening and maintained, the take-off time of the accelerator pedal is no more than 0.2 s, and the vehicle accelerates to above 140 km / h; the following indexes are calculated by using the collected test data:

[0019] the time required from the start of depressing the accelerator pedal to acceleration to 140 km / h; the time required from the start of depressing the accelerator pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration in the process of reaching the peak value of the longitudinal acceleration from the start of depressing the accelerator pedal; the arithmetic mean of the results of each valid index; and the final result of the index;

[0020] 2. Brake performance test

[0021] 2.1 Dry ground brake test

[0022] Under the full load state, the average temperature of the service brake on the hottest axle of the vehicle is confirmed to be 65-100°C, the test vehicle is accelerated to above 105 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is maintained in D, when the vehicle speed drops to 100 ± 2 km / h, the brake pedal is quickly depressed until the ABS system starts to work or the pedal force reaches 500 N, until the vehicle stops; the vehicle speed, braking distance, brake pedal force, deceleration, body pitch angle, braking stability and abnormal conditions occurring during braking are recorded; the brake test is repeated 5 times;

[0023] 2.2 Wet ground brake test

[0024] The test vehicle is accelerated to 85 ± 2 km / h on the starting section, the vehicle enters the test road, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is maintained in D, and emergency braking is performed at the same time, the ABS system is activated to act on each wheel, and the braking is maintained until the vehicle stops; the distance traveled by the test vehicle from 80 km / h to 20 km / h is recorded; the first two test data of each test are discarded, and the test vehicle completes at least 6 valid tests;

[0025] 2.3 Brake stability test

[0026] At the beginning of the test, the left and right wheels of the vehicle are located on two road surfaces with different adhesion coefficients, and the longitudinal center plane of the vehicle passes through the junction line of the high and low adhesion coefficient road surfaces; emergency full braking is performed at an initial speed of 80 km / h, and any part of the tire cannot cross the junction line until the vehicle stops, and steering wheel correction is allowed during the test; the longitudinal vehicle speed and yaw rate signals during the test are recorded; the test vehicle completes 3 valid tests on the left and right sides respectively;

[0027] 2.4 Brake pedal linearity test

[0028] Under light load, the average temperature of the service brake on the hottest axle of the vehicle is confirmed to be in the range of 65-100°C, and the brake booster is at a normal level; the test vehicle accelerates to more than 105 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is kept in D, and when the vehicle speed drops to 100±2 km / h, the brake pedal is slowly pressed until the ABS is triggered, and the deceleration changes linearly during the process. The process is prolonged, and the vehicle speed, deceleration, pedal force, pedal stroke, and ABS working condition are recorded. If the brake pedal is pressed too quickly, resulting in a vehicle speed of more than 50 km / h when the ABS is triggered, the test is invalid. The test vehicle must complete at least 3 valid tests;

[0029] 2.5 Light braking test

[0030] Under light load, the test vehicle accelerates to more than 65 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, and the automatic transmission vehicle is kept in D. When the vehicle speed drops to 60±2 km / h, the brake pedal is quickly pressed and the pedal stroke is kept constant, the brake pedal jump time is not more than 0.2s, until the vehicle stops. When the brake pedal stroke is selected, the vehicle speed in the range of 50-30 km / h and the average deceleration in the range of 1.8-2.2 m / s2 during the test are met. The vehicle speed, deceleration, and pedal stroke are recorded. The test vehicle must complete at least 3 valid tests;

[0031] 3. Handling stability test

[0032] It is carried out on dry, flat and clean cement concrete or asphalt pavement, and the slope from any direction of the test road should not be greater than 2%, and for steering wheel center zone characteristic test, the slope should not be greater than 1%;

[0033] Before the experiment, drive straight at the test speed for 10 km or along a radius of 15 m, at a corresponding vehicle speed with a lateral acceleration of 3 m / s2, drive 500 m, left and right each time, to warm up the tires. After the tire warming is completed, the test vehicle enters the test area for various tests;

[0034] 3.1 Vehicle body roll test

[0035] On the test site, draw a circle with a radius of not less than 15 m in a conspicuous color; start the vehicle and drive it along the drawn circle at the lowest steady speed, accelerating slowly and uniformly, the longitudinal acceleration not exceeding 0.25 m / s2, until the lateral acceleration of the vehicle reaches 6.5 m / s2 or the maximum lateral acceleration that can be reached under the limitation of engine power, or the vehicle becomes unstable, and record the whole process; the test is conducted in two directions, left and right, and the arithmetic mean of the results of 3 left-turn tests and 3 right-turn tests in terms of the body roll of the vehicle is taken as the final result;

[0036] 3.2 Obstacle avoidance test

[0037] Determine the distance between stakes and the length of each part according to the width of the vehicle, and arrange the stakes on the site; start the test at a preset low vehicle speed, gradually increase the vehicle speed until the test driver feels that the vehicle cannot be controlled; record the highest passing speed of obstacle avoidance, and obtain the initial vehicle speed of entering the stake area; take the maximum value of multiple test results as the final result of the highest passing speed of obstacle avoidance;

[0038] 3.3 Center zone steering characteristic test

[0039] The initial state of the test is straight-line driving at a constant speed, and the test standard speed is 100 km / h, or the test speed is increased or decreased based on 100 km / h, with a speed interval of 20 km / h; during the test, the steering wheel input is an oscillating angular input, and the preferred input form is a sine wave, with a reference frequency of 0.2 Hz and a frequency deviation of no more than 10%; the steering input during the experiment is realized by manual or steering robot;

[0040] When the steering signal is input manually, the test should last at least 40 s; when the steering signal is input by a steering robot, the test should last at least 20 s; record the steering wheel angle, steering wheel angular velocity, vehicle longitudinal acceleration and vehicle lateral acceleration during the test;

[0041] Process the test data to obtain the lateral acceleration hysteresis and the steering wheel angle hysteresis; take the arithmetic mean of the results of 3 tests for each index as the final result;

[0042] 3.4 Low-speed steering return performance test

[0043] The test vehicle drives straight along the test section at a speed of 10 ± 1 km / h, and records the zero line of each measured variable; then turn the steering wheel to the limit position, wait for stability and start recording, and then quickly release the steering wheel, and record the vehicle motion process within at least 6 s after releasing the hand; the vehicle speed remains unchanged during the recording time; the test is conducted in two directions, left and right, with 3 tests in each direction;

[0044] The residual steering wheel angle is calculated to obtain the steering wheel angle at the time of releasing the steering wheel for 5s; the arithmetic mean of the results of 3 left turns and 3 right turns of the residual steering wheel angle is taken as the final result;

[0045] 3.5 High-speed steering returnability test

[0046] The test vehicle travels straight along the test section at a speed of 100±1 km / h, and the zero line of each measured variable is recorded. Then the steering wheel is turned to make the vehicle lateral acceleration reach 2+0.2 m / s 2 After stabilization and starting recording, the steering wheel is quickly released, and the vehicle motion process within at least 4s after releasing the hand is recorded, and the accelerator pedal position remains unchanged during the recording time; the test is performed in two directions of left turn and right turn, 3 times for each direction;

[0047] The test data is processed to obtain the yaw rate overshoot; the arithmetic mean of the results of 3 left turns and 3 right turns of the yaw rate overshoot is taken as the final result;

[0048] 3.6 Steering wheel angle step input test

[0049] Before the test, travel at a speed of 100 km / h, and pre-select the steering wheel angle position at a steady-state lateral acceleration value of 4 m / s 2 The vehicle travels straight at the test speed, first gently presses the steering wheel in the input direction to eliminate the free travel of the steering wheel and start recording the zero line of each measured variable, and after 0.2-0.5s, turn the steering wheel at a speed of not more than 0.2s or a speed of not less than 200° / s to reach the pre-selected position and fix it for a few seconds until the measured variable transitions to a new steady-state value, and stop recording; keep the vehicle speed unchanged during the recording process; the test is performed in two directions of left turn and right turn; the two directions can be alternately performed, or a one-direction test is performed continuously, and then another direction test is performed;

[0050] The test data is processed to obtain the lateral acceleration response time; the arithmetic mean of the results of 3 left turns and 3 right turns of the lateral acceleration response time is taken as the final result;

[0051] 3.7 Sweep frequency test

[0052] The vehicle travels straight at a test speed of 100 ± 2 km / h, and starts under the condition of balance of yaw rate of 0 ± 0.5° / s, and performs a continuous sinusoidal input with gradually increasing frequency to the steering wheel at a predetermined steering wheel angle amplitude, the frequency gradually increases from 0.2 Hz to 3 Hz, and the time is not less than 20 s; the vehicle speed is kept unchanged during the test; the vehicle travels around a circle at the selected test speed, and the steering wheel angle when the predetermined steady-state lateral acceleration is reached is taken as the preselected steering wheel angle; the standard steady-state lateral acceleration level is 4 m / s 2 ; the effective test is repeated for 3 times;

[0053] The test data are processed to obtain the resonance frequency; the arithmetic mean of the results of 3 times is taken as the final result;

[0054] 3.8 Minimum turning diameter test

[0055] The running track display device is installed on the farthest point from the steering center, the nearest point and the center of the wheel tread on the vehicle body; the automobile is in the lowest forward gear and travels at a low vehicle speed, the steering wheel is turned to the limit position and kept unchanged, the track display device is started after stabilization, the vehicle travels one round, so that each measuring point displays a closed motion track on the ground respectively, and then the vehicle is driven out of the measuring area; the diameters of the track circles formed by each measuring point on the ground are measured with a ruler, which should be measured in two mutually perpendicular directions, and the maximum value is read by moving left and right during measurement; the arithmetic mean of the measured values in two directions is taken as the test result; the test is measured once for left turn and once for right turn, and the test results are recorded; the test data are processed to obtain the final result of the minimum turning diameter.

[0056] 3.9 Steering wheel turn number test

[0057] The test automobile is parked on the test site, the vehicle is started, the transmission is placed in neutral, the brake is released, and the steering wheel is in the intermediate position, and the zero line of each measuring variable is recorded; the force steering wheel is slowly and uniformly turned to the maximum angle to the left, then the force steering wheel is turned to the maximum angle in the opposite direction, and finally the force steering wheel is turned to the intermediate position to the left; the changes of each measuring variable during the whole process are recorded; at least three tests are performed; the average value of the test results of 3 times is taken as the final result;

[0058] 4. Overall score calculation of driving control performance

[0059] The selected test indexes are divided into first-level indexes, second-level indexes and third-level indexes; the overall score of the driving control performance is calculated according to the scores and weights of the first-level indexes, and the last one decimal place is retained, and the calculation method is formula 1:

[0060]

[0061] In the formula, S is the evaluation total score of the driving control performance, i is the serial number of the first-level index, Si and a i respectively are the score of the primary index and the weight of the primary index of the i th sequence number;

[0062] The score of the primary index is calculated according to the score of the secondary index and the weight, and the two decimal places are reserved. The calculation method is shown in the following formula 2:

[0063]

[0064] In the formula, j is the sequence number of the secondary index in the primary index, and n i is the number of the secondary index of the i th primary index. ij , b ij respectively are the score of the secondary index and the weight of the secondary index of the j th sequence number in the i th primary index;

[0065] The score of the secondary index is calculated according to the score of the tertiary index and the weight, and the two decimal places are reserved. The calculation method refers to the calculation method of the score of the primary index;

[0066] The score of the tertiary index is calculated by linear interpolation method according to the index result measured by the test and the index limit value corresponding to 60 points and 100 points, and the two decimal places are reserved. When the calculation result is greater than 100 points, it is calculated as 100 points;

[0067] The primary index includes three indexes of power driving test, braking performance test and handling stability test. The power driving test includes three secondary indexes of low-speed power driving, medium-speed power driving and high-speed power driving. Under the secondary index, a plurality of tertiary indexes are included, which include 0-30km / h acceleration time, 40-80km / h acceleration time, 100-140km / h acceleration time, acceleration pedal response time, starting impact and power system impact. The braking performance test includes five secondary indexes of braking distance, braking stability, braking pedal linearity, braking response sensitivity and braking comfort. The corresponding tertiary indexes include dry braking 100-0km / h braking distance, wet braking 80-20km / h braking distance, yaw angular velocity peak value, initial braking pedal force linearity, final braking pedal force linearity, initial braking pedal stroke linearity, slight braking response time, emergency braking response time, braking pitch angle and deceleration change rate.

[0068] The longitudinal stability test includes six secondary indexes of steady-state handling stability, transient handling stability, center zone steering characteristics, steering return performance, steering response characteristics and maneuverability. The corresponding tertiary indexes of the six secondary indexes include body roll, maximum obstacle avoidance speed, lateral acceleration hysteresis, steering wheel angle hysteresis, residual steering wheel angle, yaw angular velocity overshoot, lateral acceleration response time, resonance frequency, minimum turning diameter and steering wheel turns.

[0069] The test method of the present application is a systematic and reasonable whole vehicle driving control performance product force test and evaluation method based on actual travel conditions in China, which can directly reflect the whole vehicle driving control performance under the actual travel scene of Chinese consumers. It is used for the host factory to calibrate and verify the whole vehicle driving control performance strategy of the engineering prototype in the development or verification stage by using the test and evaluation conditions mentioned in the present application, so as to achieve the positioning of the whole vehicle development target. BRIEF DESCRIPTION OF DRAWINGS

[0070] Figure 1 is a flow chart of the whole vehicle driving control performance product force test and evaluation method based on actual travel conditions.

[0071] Figure 2 is a schematic diagram of the obstacle avoidance playground performance site.

[0072] Figure 3 is a relationship curve between the body roll angle and the lateral acceleration.

[0073] Figure 4 is a schematic diagram of the hysteresis loop.

[0074] Figure 5 is a yaw rate time history curve.

[0075] Figure 6 is a lateral acceleration response curve.

[0076] Figure 7 is the amplitude-frequency phase-frequency characteristic diagram of the automobile. DETAILED DESCRIPTION

[0077] The present application will be further described in detail below in combination with the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0078] Referring to Figure 1 the whole vehicle driving control performance product force test and evaluation method based on actual travel conditions of the embodiment of the present application is tested and evaluated by the following steps:

[0079] 1. Dynamic driving test

[0080] 1.1 Test site

[0081] (1) The road surface should be clean, dry, straight concrete or asphalt (or similar) road surface, and the longitudinal slope should not be greater than 0.1%.

[0082] (2) The road surface should be paved in the same period, the road surface should be flat, the structure should be uniform, the abrasion should be consistent, and the surface should be free of loose materials or foreign deposits.

[0083] (3) The pavement texture depth measured by the sand patch method according to ASTM E 965-96 shall be 0.7 mm ± 0.3 mm.

[0084] 1.2 Environmental Conditions

[0085] The test shall be conducted when the atmospheric temperature is between 0 °C and 40 °C, without fog, rain or hail, and with a wind speed not greater than 3 m / s.

[0086] 1.3 Test Equipment

[0087] 1.3.1 Test Vehicle

[0088] (1) The test vehicle shall be a standard two-axle passenger car that can accommodate the test tire, and the powertrain and suspension systems of the test vehicle shall be in good working order. Prior to the start of objective testing, the test vehicle shall be run-in for 1000 km on the selected test site, and the vehicle shall be inspected after run-in to ensure that all systems are in good condition.

[0089] (2) The original equipment tires shall be used, with good tread, and the tire tread depth shall be more than 90% of the original tire tread depth, with no significant uneven wear, and the inflation pressure shall meet the requirements for the vehicle. If the original equipment tires are damaged, they shall be replaced with tires of the same brand and model as the original equipment tires.

[0090] (3) The original equipment lubricant shall be used, and if it must be replaced due to an accident, the same brand and model as the original equipment lubricant shall be used. The fuel shall be provided by the same supplier, and the fuel grade shall be the minimum grade specified for the vehicle.

[0091] (4) For vehicles with different driving modes, the default mode of the vehicle shall be selected for testing. If the vehicle does not have a default mode, the comfort mode or standard mode shall be selected for testing. For vehicles equipped with an automatic transmission, the "D" range shall be used for testing. For vehicles that can manually select two-wheel drive and four-wheel drive modes, the two-wheel drive mode shall be selected for testing.

[0092] 1.3.2 Test Instrumentation

[0093] (1) The test instrumentation shall be able to withstand dust, impact, vibration, and 100% humidity.

[0094] (2) The test vehicle shall be equipped with speed and acceleration acquisition equipment that meets the test requirements. The measurement range and maximum error of the instrumentation shall meet the requirements of Table 1.

[0095] Table 1 Measurement Range and Maximum Error of Instrumentation

[0096] Measurement parameter and unit Measurement range Test instrument and recording system error Longitudinal acceleration / (m / s 2 )]]> -20～20 ±0.1 Longitudinal speed / (km / h) 0～200 0.2

[0097] 1.4 Test Procedure

[0098] The vehicle should be preheated before the start of the test. All types of vehicles should be driven at 80% of the maximum speed estimated by the manufacturer for 30 minutes. The power battery SOC of the pure electric vehicle should be above 80%. The power battery SOC value of the hybrid vehicle should be displayed full on the instrument, and the preheating driving process should be carried out in the hybrid mode.

[0099] 1.4.1 Low-speed power driving test

[0100] The vehicle is accelerated from a stationary state to 30 km / h at 30% throttle opening.

[0101] During the test process of the manual transmission vehicle, the vehicle is stationary, the transmission is placed in forward gear 1, the accelerator pedal is quickly depressed to 30±1% opening and maintained, and the clutch is released. The clutch should be operated to maximize the acceleration performance, and the vehicle is accelerated to above 30 km / h. When the vehicle is moving, the recording device is triggered, and the recording is stopped when the speed is greater than 30 km / h. During the test process of the automatic transmission and single-stage reducer vehicle, the vehicle is stationary, the transmission is placed in "D" gear, and the engine is in idle state. After releasing the brake, the accelerator pedal is immediately depressed to 30±1% opening and maintained (the take-off time of the accelerator pedal is not more than 0.2s), and the vehicle is accelerated to above 30 km / h. When the accelerator pedal is depressed, the recording device is triggered, and the recording is stopped when the speed is greater than 30 km / h. For fuel vehicles, the test should be carried out in both directions, at least 3 times in each direction; for pure electric vehicles and hybrid vehicles, the test should be carried out in both directions, at least 1 time in each direction.

[0102] The following indicators are calculated using the collected test data: the time required for a manual transmission vehicle to accelerate from the start of vehicle movement to 30 km / h; the time required for an automatic transmission vehicle to accelerate from the start of the accelerator pedal to 30 km / h. The time required from the start of the accelerator pedal to the longitudinal acceleration (3Hz low-pass filter) reaching 50% of the peak value. The maximum slope of the longitudinal acceleration (10Hz low-pass filter) during the process of the longitudinal acceleration reaching the peak value from the start of the accelerator pedal. The arithmetic mean of the results of each valid indicator is the final result of the indicator.

[0103] 1.4.2 Medium-speed power driving test

[0104] The vehicle is driven at a constant speed of not less than 50 km / h, the accelerator pedal is released, and the vehicle is coasted to 40±1 km / h. Immediately, the accelerator pedal is depressed to 60±1% opening and maintained (the take-off time of the accelerator pedal is not more than 0.2s), and the vehicle is accelerated to above 80 km / h.

[0105] For manual transmission vehicles, the transmission is set to 3rd gear, and the recording device is triggered when the accelerator pedal is depressed. The recording stops when the vehicle speed is greater than 80 km / h. For automatic transmission and single reduction vehicles, the transmission is set to "D" gear, and the recording device is triggered when the accelerator pedal is depressed. The recording stops when the vehicle speed is greater than 80 km / h. For gasoline vehicles, the test should be conducted in both directions, with at least 3 runs in each direction. For pure electric vehicles and hybrid vehicles, the test should be conducted in both directions, with at least 1 run in each direction.

[0106] Using the collected test data, the following indicators are calculated: the time required to accelerate from the start of the test to 80 km / h. The time required to accelerate from the start of the test to the 50% of the peak longitudinal acceleration (3 Hz low-pass filter). The maximum slope of the longitudinal acceleration (10 Hz low-pass filter) during the process of reaching the peak longitudinal acceleration. The arithmetic mean of the results of each valid indicator is the final result of this indicator.

[0107] 1.4.3 High-speed power driving test

[0108] The vehicle is driven at a constant speed of not less than 110 km / h, the accelerator pedal is released, and the vehicle is coasted to 100 ± 1 km / h. Immediately, the accelerator pedal is depressed to 100% opening and maintained (the start-up time of the accelerator pedal is not greater than 0.2 s), and the vehicle accelerates to above 140 km / h.

[0109] For manual transmission vehicles, the transmission is set to 4th gear, and the recording device is triggered when the accelerator pedal is depressed. The recording stops when the vehicle speed is greater than 140 km / h. For automatic transmission and single reduction vehicles, the transmission is set to "D" gear, and the recording device is triggered when the accelerator pedal is depressed. The recording stops when the vehicle speed is greater than 140 km / h. For gasoline vehicles, the test should be conducted in both directions, with at least 3 runs in each direction. For pure electric vehicles and hybrid vehicles, the test should be conducted in both directions, with at least 1 run in each direction.

[0110] Using the collected test data, the following indicators are calculated: the time required to accelerate from the start of the test to 140 km / h. The time required to accelerate from the start of the test to the 50% of the peak longitudinal acceleration (3 Hz low-pass filter). The maximum slope of the longitudinal acceleration (10 Hz low-pass filter) during the process of reaching the peak longitudinal acceleration. The arithmetic mean of the results of each valid indicator is the final result of this indicator.

[0111] 2. Brake performance test

[0112] 2.1 Dry ground brake test method

[0113] 2.1.1 Test conditions

[0114] (1) The mass state of the vehicle shall meet the corresponding requirements of each test.

[0115] (2) Each test shall be conducted at the corresponding specified speed; if the maximum design speed of the vehicle is lower than the specified test speed, the test shall be conducted at the maximum design speed.

[0116] (3) During the test, the force applied to the brake control device to achieve the specified braking performance shall not exceed the specified maximum value.

[0117] (4) The test road surface shall have good adhesion, and the test road shall be a high adhesion coefficient road with an adhesion coefficient of about 0.8.

[0118] (5) The test shall be conducted under wind conditions that do not affect the test results.

[0119] (6) At the beginning of the test, the tires shall be cold and at the specified pressure corresponding to the actual load of the wheels when the vehicle is stationary.

[0120] (7) The specified performance shall be achieved without wheel lock, vehicle deviation from the 3.5m wide test lane, lateral angle less than or equal to 15°, and no abnormal vibration at a speed greater than 15km / h.

[0121] 2.1.2 Instruments and equipment

[0122] Table 2 Measurement range and maximum error of instruments and equipment

[0123]

[0124] 2.1.3 Vehicle load

[0125] The vehicle test load is full load, i.e. loaded to the maximum design total mass of the vehicle.

[0126] 2.1.4 Test method

[0127] Under full load, the average temperature of the service brake on the hottest axle of the vehicle is confirmed to be 65-100°C, the test vehicle is accelerated to more than 105km / h, the accelerator pedal is released, the manual transmission model is shifted to neutral, the automatic transmission model is kept in D, when the vehicle speed drops to 100±2km / h, the brake pedal is quickly depressed until the ABS system starts working or the pedal force reaches 500N, until the vehicle stops. Record the vehicle speed, braking distance, brake pedal force, deceleration, vehicle body pitch angle, braking stability and abnormal conditions during braking. Repeat the braking test 5 times.

[0128] During each test, the brake control force shall not exceed the maximum allowable value (≤500N), and the vehicle body shall not deviate from the specified lane. If the test conditions do not meet the above requirements, the test result is invalid and needs to be repeated.

[0129] 2.1.5 Data processing and result expression

[0130] (1) Dry braking distance 100-0 km / h

[0131] The actual braking distance (S2) shall be corrected to the dry braking distance 100-0 km / h (S1) according to the following formula:

[0132]

[0133] Where: V 规定 is the specified initial speed, i.e. 100 km / h; V 实际 is the actual initial speed.

[0134] The shortest braking distance in 5 tests is taken as the final result of the dry braking distance 100-0 km / h.

[0135] (2) Emergency braking response time

[0136] The time required from the brake pedal being depressed to the longitudinal deceleration reaching 6 m / s 2 . The arithmetic mean of the emergency braking response times in 5 tests is taken as the final result of the emergency braking response time.

[0137] (3) Braking pitch angle

[0138] The average value of the vehicle body pitch angle in the speed range of 80 km / h to 20 km / h during braking. The arithmetic mean of the braking pitch angles in 5 tests is taken as the final result of the braking pitch angle.

[0139] 2.2 Wet braking test method

[0140] 2.2.1 Test conditions

[0141] (1) The slope of the test road surface shall not be greater than 2% and shall be uniform, and the slope in the length or width direction of the test road surface shall not be greater than 6 mm when measured with a 3 m straight ruler.

[0142] (2) The materials, laying period and corrosion of the road surface shall be consistent, and there shall be no loose materials and foreign objects on the road surface.

[0143] (3) The road surface shall use dense asphalt mixture materials, and the maximum nominal size of the stone shall be 8 mm to 13 mm.

[0144] (4) The sand layer of the road surface shall be tested according to ASTM E965-96 and shall be 0.7 mm ± 0.3 mm.

[0145] (5) The wet friction characteristics of the test road surface shall meet one of the following two:

[0146] a) British Pendulum Number (BPN) method

[0147] The average BPN value, after correction by the temperature correction formulae (4) and (5), should be between 42 and 60 when tested by the pendulum tester. The test road should be divided into 10 m sections and the BPN value should be tested according to ASTM E303-93, with 5 repeats for each section. The coefficient of variation of the average BPN value should be no more than 10%.

[0148] Temperature correction value = -0.0018(t-20) + 0.34t - 6.1 (2) 2

[0149] BPN = BPN (measured) + temperature correction value (3)

[0150] Where: t = temperature of the test road in degrees Celsius (°C).

[0151] The BPN value of the test road should not change with the entire braking distance in order to reduce the dispersion of the test results. The friction block compound formulation and physical properties should comply with the relevant requirements. The slider block should be replaced when the wear reaches a flat of 3.2 mm or a vertical distance of 1.6 mm, which is the maximum wear level, according to the requirements of ASTM E303-93.

[0152] b) Standardized Tire Test (SRTT) method

[0153] The average peak braking coefficient, after correction by the temperature correction formulae (4) and (5), should be 0.7 ± 0.1 when measured by the trailer method at a test speed of 65 km / h. The test road should be selected from a road section of 10 m or less, and the braking position on the test road should be within 2 m of the test position.

[0154] Temperature correction value = -0.0035(t-20) (4)

[0155] Average peak braking coefficient (μ peak ave ) = peak braking coefficient (measured) + temperature correction value (5)

[0157] Where: t = temperature of the test road under wet conditions in degrees Celsius (°C).

[0158] (6) The water spray device should be located on the side of the test road or on the special tire test vehicle (trailer). If the water spray is located on the side of the test road, the water should be sprayed for at least 0.5 h before the test to allow the test road temperature to reach equilibrium with the water temperature.

[0159] ​(7) During the whole test, the water film thickness should be kept at 1.0 mm ± 0.5 mm, and the water film thickness should be uniform during the whole test cycle.

[0160] (8) The interference of wind speed on the wet road surface should be avoided, and a barrier device can be used if necessary.

[0161] (9) The temperature of the wet road surface and the surrounding environment should be 2℃ to 20℃ when testing snow tires, and 5℃ to 35℃ when testing ordinary tires. The temperature of the wet road surface should not change by more than 10℃ during the test. The temperature of the surrounding environment should be similar to that of the wet road surface, and the temperature difference should not exceed 10℃.

[0162] (10) Before the test, check the inflation pressure of the vehicle tires at the ambient temperature, and adjust the tire pressure to the specified air pressure under the full load condition of the vehicle.

[0163] 2.2.2 Instruments and equipment

[0164] (1) The test instruments should be able to withstand dust, impact, vibration, 100% humidity and other environmental conditions.

[0165] (2) The test vehicle should be equipped with speed and distance sensors that meet the test requirements. The speed of the test vehicle should be measured using a five-wheel instrument or other non-contact speed measurement instrument, including Vbox, radar, GPS and other measurement systems.

[0166] (3) The allowable error is as follows:

[0167] - Vehicle speed: ± 1% of vehicle speed or 0.5 km / h, whichever is greater;

[0168] - Distance: ± 0.1 m

[0169] (4) During the test, the test vehicle should display the difference between the time speed and the standard speed, so that the driver can adjust the vehicle speed.

[0170] 2.2.3 Vehicle load

[0171] The vehicle test load is full load, i.e. loaded to the maximum design total mass of the vehicle.

[0172] 2.2.4 Test method

[0173] The test vehicle is accelerated to 85 ± 2 km / h on the starting section, the vehicle enters the test road, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is kept in D range, the emergency brake is applied, the ABS system is activated to act on each wheel, and the braking is maintained until the vehicle stops. Each braking test must be strictly controlled in the same test area, and the actual driving distance of each test must be within 5 m longitudinally and 0.5 m laterally. The distance traveled by the test vehicle from 80 km / h to 20 km / h is recorded. The first two test data of each test are discarded, and the test vehicle must complete at least 6 valid tests.

[0174] 2.2.5 Data processing and result expression

[0175] For any two consecutive groups of three test tires and test data of the test tires, if the coefficient of variation of the average braking distance is greater than 3%, the test data of the standard test tires and the test tires are discarded and retested, and the coefficient of variation of the average braking distance is calculated according to formula (8):

[0176]

[0177] In the formula: C.V. - coefficient of variation, %; S - standard deviation; A - average value of average braking distance.

[0178] The arithmetic mean of the 80-20 km / h braking distance on wet ground in the 6 test results is taken as the final result.

[0179] 2.3 Braking stability test method

[0180] 2.3.1 Test conditions

[0181] (1) The mass state of the vehicle should meet the corresponding requirements of each type of test.

[0182] (2) Each type of test should be carried out at the corresponding specified speed; if the maximum design speed of the vehicle is lower than the specified test speed, the test should be carried out at the maximum design speed.

[0183] (3) During the test, the force applied to the brake control device to achieve the specified braking performance should not exceed the specified maximum value.

[0184] (4) The test road is a split road with a high adhesion coefficient k H ≥ 0.5, and the adhesion coefficients of the low adhesion coefficient road and the high adhesion coefficient road should meet the requirement of k H / k L ≥ 2.

[0185] (5) The test should be carried out under wind conditions that do not affect the test results.

[0186] (6) At the beginning of the test, the tires shall be cold and at the specified pressure corresponding to the actual load of the wheels when the vehicle is stationary.

[0187] (7) The specified performance shall be achieved without occurrence of wheel lock, vehicle departure from the 3.5 m wide test lane, lateral angle less than or equal to 15° and without abnormal vibration at a vehicle speed greater than 15 km / h.

[0188] 2.3.2 Instruments and apparatus

[0189] The measuring range and maximum error of the instruments and apparatus shall meet the requirements in Table 5.

[0190] Table 3 Measuring range and maximum error of instruments and apparatus

[0191]

[0192] 2.3.3 Vehicle load

[0193] The test load condition is light load, i.e. the total mass of the test vehicle, test equipment and the driver and test operator.

[0194] 2.3.4 Test method

[0195] At the beginning of the test, the left and right wheels of the vehicle are located on two road surfaces with different (k H , k L ) adhesion coefficients, and the longitudinal center plane of the vehicle passes through the junction line of the high and low adhesion coefficient road surfaces. Emergency full braking is performed at an initial speed of 80 km / h, and any part of the tire cannot cross the junction line until the vehicle stops. Steering wheel correction is allowed during the test. Record the longitudinal vehicle speed and lateral angular velocity signals during the test. The left and right sides of the test vehicle each complete 3 valid tests.

[0196] 2.3.5 Data processing and result expression

[0197] Calculate the peak lateral angular velocity: the maximum value of the absolute value of the lateral angular velocity within 2 s after the brake pedal is depressed. The arithmetic mean of the results of 6 tests is taken as the final result.

[0198] 2.4 Brake pedal linearity test method

[0199] 2.4.1 Test conditions

[0200] The same as 2.1.1.

[0201] 4.2 Instruments and apparatus

[0202] The same as 2.1.2.

[0203] 2.4.3 Vehicle load

[0204] The test load state is a light load state, i.e. the total mass of the test vehicle, test equipment and the driver and test personnel after being fully loaded.

[0205] 2.4.4 Test method

[0206] Under the light load state, the average temperature of the service brake on the hottest axle of the vehicle is confirmed to be in the range of 65-100°C, and the brake booster is at a normal level. The test vehicle is accelerated to above 105 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, and the automatic transmission vehicle is kept in D. When the vehicle speed drops to 100±2 km / h, the brake pedal is slowly pressed at a constant speed until the ABS is triggered to work. The process requires the deceleration to change linearly, and the pressing process is as long as possible. The vehicle speed, deceleration, pedal force, pedal stroke, and ABS working condition are recorded. If the brake pedal is pressed too quickly, resulting in the vehicle speed being above 50 km / h when the ABS is triggered to work, the test is invalid. The test vehicle completes at least 3 valid tests.

[0207] 2.4.5 Data processing and result expression

[0208] (1) Initial brake pedal force linearity

[0209] The brake pedal force and deceleration signals collected during the test are intercepted, and the brake pedal force and deceleration in the range of pedal stroke greater than 5 mm to deceleration reaching 4 m / s2 are selected to calculate the linearity, and the calculation method is shown in formula 9.

[0210]

[0211] In the formula: R 2 — linearity; F— brake pedal force (N·m); A— deceleration (m / s 2 ).

[0212] (2) Final brake pedal force linearity

[0213] The brake pedal force and deceleration signals collected during the test are intercepted, and the brake pedal force and deceleration in the range of deceleration of 5-8 m / s2 are selected to calculate the linearity, and the calculation method is shown in formula 9.

[0214] (3) Initial brake pedal stroke linearity

[0215] The brake pedal stroke and deceleration signals collected during the test are intercepted, and the brake pedal stroke and deceleration in the range of pedal stroke greater than 5 mm to deceleration reaching 4 m / s2 are selected to calculate the linearity, and the calculation method is shown in formula 10.

[0216]

[0217] wherein: R 2 Linearity; S - Brake pedal stroke (mm); A - Deceleration (m / s 2 ).

[0218] The arithmetic mean of the results of each effective indicator is taken as the final result of the indicator.

[0219] 2.5 Light braking test method

[0220] 2.5.1 Test conditions

[0221] As 2.1.1.

[0222] 2.5.2 Instrumentation

[0223] As 2.1.2.

[0224] 2.5.3 Vehicle load

[0225] The test load condition is light load condition, i.e. the total mass of the test vehicle, test equipment and the driver and test operator after preparation.

[0226] 2.5.4 Test method

[0227] Under light load condition, the test vehicle accelerates to above 65 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral gear, and the automatic transmission vehicle is kept in D gear. When the vehicle speed drops to 60 ± 2 km / h, the brake pedal is quickly pressed and the pedal stroke is kept unchanged (the brake pedal jump time is not more than 0.2 s), until the vehicle stops. The brake pedal stroke is selected to meet the condition that the average deceleration of the vehicle speed in the range of 50-30 km / h during the test is in the range of 1.8-2.2 m / s 2 . The vehicle speed, deceleration and pedal stroke are recorded. The test vehicle completes at least 3 effective tests.

[0228] 2.5.5 Data processing and result expression

[0229] (1) Light braking response time

[0230] The average deceleration Ax 50-30 of the vehicle speed in the range of 50-30 km / h is calculated, and the light braking response time is the time required from the start of pressing the brake pedal to the deceleration reaching 90% of Ax 50-30 .

[0231] (2) Deceleration rate of change

[0232] The calculation method of the deceleration rate of change is shown in formula 11.

[0233]

[0234] where: K = deceleration rate of change; Ax = average deceleration (m / s2) over the speed range 50-30 km / h 50-30 average deceleration (m / s2) over the speed range 50-30 km / h 2 )Ax 10-5 average deceleration (m / s2) over the speed range 10-5 km / h 2 ).

[0235] The arithmetic mean of the results of each valid indicator is taken as the final result of the indicator.

[0236] 3. Test of steering stability

[0237] 3.1 Test site

[0238] (1) The test shall be carried out on a dry, level and clean, cement concrete or asphalt paved surface, and the slope in any direction from the test surface shall not exceed 2%, and for the test of the steering wheel centering characteristics, the slope shall not exceed 1%.

[0239] (2) The surface shall be of the same period of construction, and the surface shall be even, uniform in structure and consistent in abrasion, and the surface shall be free of loose materials or extraneous deposits.

[0240] 3.2 Environmental conditions

[0241] The average wind speed during the test shall not exceed 5 m / s, the atmospheric temperature shall be within the range of 0°C to 40°C, and the weather condition shall be free of rain, snow and fog.

[0242] 3.3 Test equipment

[0243] 3.3.1 Test vehicle

[0244] (1) Before the test, the wheel alignment parameters shall be measured, the steering and suspension systems shall be inspected, adjusted and fastened, and the lubrication shall be carried out according to the provisions. Only when it is determined that the test vehicle has met the technical conditions specified by the manufacturer, the test can be carried out.

[0245] (2) New tires shall be used for the test, and the tires shall be run-in for at least 200 km before the test; if old tires are used, the remaining tread depth of the tire crown shall be not less than 1.6 mm at the end of the test. The tire pressure shall meet the technical requirements of the vehicle manufacturer.

[0246] (3) The test load state is the light load state, i.e. the total mass of the test vehicle, the test equipment and the driver and the test operator.

[0247] 3.3.2 Test instruments

[0248] (1) The test instruments shall be able to withstand the environmental conditions of dust, impact, vibration and 100% humidity.

[0249] (2) Test equipment required: vehicle speedometer; steering wheel torque and steering wheel angle measuring instrument; vehicle handling stability tester; stopwatch; multi-channel data acquisition system.

[0250] (3) The measurement range and maximum error of each measuring instrument meet the requirements of Table 6.

[0251] Table 4 Measurement range and maximum error of measuring instruments

[0252]

[0253]

[0254] 3.4 Test procedure

[0255] Before the test, the test vehicle is driven at a constant speed for 10 km, or along a circle with a radius of 15 m at a lateral acceleration of 3 m / s 2 for 500 m (once to the left and once to the right) to warm up the tires. After the tires are warmed up, the test vehicle enters the test area to perform the tests.

[0256] 3.4.1 Vehicle body roll test

[0257] The test load state is light load. On the test site, draw a circle with a radius of not less than 15 m in a conspicuous color. Start the vehicle and drive it along the drawn circle at the lowest stable speed, slowly and uniformly accelerating (the longitudinal acceleration should not exceed 0.25 m / s 2 ), until the lateral acceleration of the vehicle reaches 6.5 m / s 2 (or the maximum lateral acceleration that can be reached due to engine power limitations, or the vehicle becomes unstable), and record the entire process. The test is performed in two directions, to the left and to the right, and each direction is tested three times. At the start of each test, ensure that the longitudinal symmetry plane of the vehicle body is in the center of the drawn circle.

[0258] The true value of the lateral acceleration (unit, m / s 2 ) is equal to the instantaneous yaw rate (unit, rad / s) multiplied by the instantaneous speed of the vehicle (unit, m / s).

[0259] Draw the relationship curve of the body roll angle and the lateral acceleration in the form of Figure 2 . See the relationship curve of the body roll angle and the lateral acceleration shown in Figure 2 .

[0260] Find the body roll Kφ, which is the average slope (calculated by dividing the longitudinal coordinate value by the horizontal coordinate value) of the body roll angle and the lateral acceleration relationship curve at a lateral acceleration of 2 m / s 2 .

[0261] The arithmetic average of the results of the three left turns and the three right turns of the body roll is taken as the final result.

[0262] 3.4.2 Obstacle avoidance test

[0263] The test load state is light load. According to Table 5, the post spacing and the length of each part are determined according to the vehicle width, and the posts are arranged on the site as shown in Figure 3 Figure 3 The black dots in the figure represent the positions of the posts, and 6 in the figure represents the offset. Table 5 Obstacle avoidance maneuver performance site parameters

[0264] Serial number Length (m) Offset (m) Width b (m) 1 12 ---- 1.1×w+0.25 2 13.5 ---- ---- 3 11 1 w+1 4 12.5 ---- ---- 5 12 ---- 1.3 x w + 0.25, but not less than 3

[0265] In Table 5, w represents the vehicle width, No. 1 is the length of the site corresponding to two rows of posts, 12 m, No. 2 is the length of the site without posts, 13.5 m, No. 3 is the length of the site corresponding to two rows of posts offset on one side, 11 m, No. 4 is the length of the site without posts, 12.5 m, and No. 5 is the length of the site corresponding to two rows of posts, 12 m, which forms a straight line of the vehicle with the two rows of posts in No. 1, and the space between the two rows of posts is used for the vehicle to pass through.

[0266] Before the test, turn on each test instrument and preheat it to the normal working temperature. The test driver should have rich driving experience, and before the formal test, practice the route shown in the figure several times;

[0267] During the formal test, the test vehicle with a manual transmission will have the gear position at the highest gear, and the test vehicle with an automatic transmission will have the gear position at the "D" gear. The vehicle enters the first test section at a certain speed. After entering the first section (as shown in Figure 3 ) for 2 m, release the accelerator pedal, and the engine runs in the engaged state through the subsequent passage; record the vehicle parameters and the time through the post area during the entire process. The test starts at a lower speed (here it refers to the speed of entering the first section, recommended at 50 km / h), and gradually increases the speed until the test driver feels that the vehicle cannot be controlled.

[0268] Record the highest obstacle avoidance passing speed (the initial speed of the vehicle entering the post area). Take the maximum value of the results of multiple tests as the final result of the highest obstacle avoidance passing speed.

[0269] 3.4.3 Center zone steering characteristic test

[0270] The test load state is light load. Turn on the instrument power supply and make it reach the normal working temperature. The initial state of the test is constant speed straight running, and the test standard speed is 100 km / h. Alternatively, 100 km / h can be taken as the reference, and the test speed can be increased or decreased (the speed interval is 20 km / h).

[0271] ​The steering wheel input is an oscillating angular input, preferably a sinusoidal input, but other inputs (e.g. triangular input) can also be used. The reference value of the steering wheel input frequency is 0.2 Hz, with a frequency deviation of ±10%. The amplitude of the input angular velocity should be sufficient to achieve a peak lateral acceleration of the vehicle of the reference value, with a peak deviation of ±10%. In order to obtain good test data and to ensure that the vehicle and its subsystems are operated in a range beyond the hysteresis, the reference value of the peak lateral acceleration is 2 m / s 2 , but smaller values or other values not exceeding 4 m / s 2 may also be used. 2

[0272] During the entire test, the steering wheel angular amplitude and the angular velocity through the center should be kept as constant as possible. The accelerator pedal position should be varied as little as possible, provided that the longitudinal speed of the vehicle is within the specified range. The variation of the longitudinal speed within the data segment used for data analysis should not exceed ±3% of the test speed.

[0273] All measured parameters are recorded during the entire test, including the measured variables in the initial driving state. In order to ensure that the test is not affected by the use of the instrument, the data recording should continue for at least 1 s after the end of the entire test.

[0274] The steering input during the test can be achieved by a human or a steering robot. When a human is used to input the steering signal, the test should last at least 40 s to ensure that at least 8 input cycles are obtained. When the test site limits do not allow for sufficiently long and consistent continuous data, a series of short data can be combined for test analysis. In this case, at least 20 cycles of data should be ensured and appropriate statistical methods should be used to process the test data, and the statistical methods should be included in the test report. When a steering robot is used to input the steering signal, the test should last at least 20 s to ensure that at least 4 input cycles are obtained.

[0275] The true value of the lateral acceleration (unit, m / s 2 ) is equal to the instantaneous yaw rate (unit, rad / s) multiplied by the instantaneous speed of the vehicle (unit, m / s).

[0276] The measured time histories are screened to select cycles with good steering wheel angular and vehicle lateral acceleration data for data analysis. The steering wheel angular and vehicle lateral acceleration data are plotted in a rectangular coordinate system, and the graph is a group of hysteresis loops formed by superimposing a plurality of hysteresis loops, and the number of hysteresis loops is equal to the number of cycles selected.

[0277] The group of hysteresis loops should be averaged in an appropriate manner, and the recommended method is to use the following equation: Figure 4 ​The upper and lower parts of the test curve in the interval A are fitted by polynomials respectively, and the fitting order is 3. When processing the data, first determine the data coordinate interval, and then select interval A in the interval according to a certain proportion. When selecting, make sure that interval A is large enough to cover the data region of interest, but avoid the influence of hysteresis effect at both ends. The recommended proportion of the coordinate interval is 50%-70%.

[0278] It is recommended to perform linear fitting by fitting polynomials in the data region of interest to estimate the slope. The average slope should be fitted in the specified region, and the transient slope should be fitted in a small region near the point of interest. The typical region value is ±0.1 m / s 2 of the lateral acceleration change. Each hysteresis loop can be analyzed separately, and the characteristic parameters of each loop are averaged to obtain the final result. Through polynomial fitting of the hysteresis loop group, the following parameters can be obtained: longitudinal coordinate hysteresis region, transverse coordinate hysteresis region, slope. The hysteresis loop diagram obtained is as follows, Figure 4 Figure 4 , wherein 1 is the longitudinal coordinate hysteresis region; 2 is the transverse coordinate hysteresis region; A is the polynomial fitting region. As Figure 4 Draw the lateral acceleration versus steering wheel torque curve and the steering wheel angle versus steering wheel torque curve to obtain the lateral acceleration hysteresis and the steering wheel angle hysteresis. Take the arithmetic mean of the results of 3 tests of each index as the final result.

[0279] 3.4.4 Low-speed steering return performance test

[0280] The test load state is light load. The test vehicle drives straight along the test section at a speed of 10±1 km / h, and the zero lines of various measured variables are recorded. Then turn the steering wheel to the limit position, wait for stability and start recording, and then quickly release the steering wheel. Record the vehicle motion process within at least 6s after releasing the hand, and the vehicle speed remains unchanged during the recording time. The test is performed in two directions of left turn and right turn, with 3 times in each direction.

[0281] Calculate the residual steering wheel angle: the steering wheel angle at 5s when the steering wheel is released. Take the arithmetic mean of the results of 3 left turn tests and 3 right turn tests of the residual steering wheel angle as the final result.

[0282] 3.4.5 High-speed steering return performance test

[0283] The test vehicle drives straight along the test section at a speed of 100±1 km / h, and the zero lines of various measured variables are recorded. Then turn the steering wheel to make the vehicle lateral acceleration reach (2+0.2) m / s 2 , wait for stability and start recording, and then quickly release the steering wheel. Record the vehicle motion process within at least 4s after releasing the hand, and the accelerator pedal position remains unchanged during the recording time. The test is performed in two directions of left turn and right turn, with 3 times in each direction.​

[0284] The yaw rate time history curve is plotted, on which the ratio of the part of the yaw rate response exceeding the new steady state value to the initial value (see Fig. 6) is plotted. Figure 5 The yaw rate overshoot is determined by equation (10):

[0285]

[0286] where: - the mean value of the yaw rate overshoot, %; σ i - the yaw rate overshoot of the i-th test, %.

[0287] Figure 5 The yaw rate response: the arithmetic mean of the results of 3 left turn tests and 3 right turn tests of the yaw rate overshoot is taken as the final result.

[0288] 3.4.6 Steering wheel angle step input test

[0289] The test load state is the light load state. Before the test, the vehicle is driven at a speed of 100 km / h, and the position of the preselected steering wheel angle is determined according to the steady state lateral acceleration value of 4 m / s 2 . The vehicle is driven straight at the test speed, the steering wheel is gently pressed in the input direction to eliminate the free travel of the steering wheel, and the zero line of each measured variable is recorded. After (0.2-0.5) s, the steering wheel is turned at the fastest speed (the rise time is not more than 0.2 s or the rise speed is not less than 200° / s) to reach the preselected position and is fixed for a few seconds (until the measured variable transitions to the new steady state value) to stop recording. The vehicle speed is kept constant during the recording process.

[0290] The test is performed in two directions, left turn and right turn. The two directions can be alternately performed, or a test in one direction is continuously performed, and then a test in the other direction is performed.

[0291] If Figure 6 The curve is plotted, and the lateral acceleration response time is obtained. The arithmetic mean of the results of 3 left turn tests and 3 right turn tests of the lateral acceleration response time is taken as the final result.

[0292] 3.4.7 Sweep frequency test

[0293] The test load was lightly loaded. The vehicle traveled in a straight line at a test speed of 100±2 km / h, starting under equilibrium conditions with a yaw rate of 0±0.5° / s. A continuous sinusoidal input was applied to the steering wheel with a predetermined steering wheel angle amplitude, gradually increasing in frequency from 0.2 Hz to 3 Hz, for a duration of at least 20 seconds. The vehicle speed was kept constant throughout the test. The test vehicle traveled in a circle at the selected test speed, and the steering wheel angle at which the predetermined steady-state lateral acceleration was reached was used as the pre-selected steering wheel angle. The standard steady-state lateral acceleration level was 4 m / s². 2 Repeat the valid experiment 3 times.

[0294] The vehicle speed and steering wheel angle time history (vt and θ-t curves) recorded during the test should be displayed on the computer. The actual vehicle speed variation should not exceed ±5% of the specified speed. The zero line of the steering wheel angle should be consistent before and after the pulse input is made by turning the steering wheel. When the difference is no greater than ±10% of the maximum steering wheel angle, the line connecting the start and end points of the steering wheel pulse input should be used as the reference zero line; if the vehicle speed variation exceeds 10%, the test record is invalid.

[0295] The amplitude-frequency and phase-frequency characteristics of the steering wheel angle pulse input and yaw rate response are calculated and analyzed on a dedicated signal processing device or on a general-purpose computer according to formula (11).

[0296]

[0297] In the formula: r(t) — yaw rate time history; δ sw (t) — Steering wheel angle time history;

[0298] ω0—The minimum angular frequency used in the calculation, typically 0.2π.

[0299] k = 1, 2, 3, ..., n

[0300] Based on the average value of the processed test data, the amplitude-frequency and phase-frequency characteristic diagrams of the car are plotted for turning the steering wheel left and right, respectively. Figure 7 As shown ( Figure 7 The horizontal axis is a logarithmic scale representing frequency, but a linear scale can also be used. The horizontal axis should be between 0Hz and 3Hz. The vertical axis represents the phase lag angle and amplitude ratio. The resonant frequency f is... p This is the frequency corresponding to the resonant peak of the amplitude-frequency response. When there is no obvious resonant peak, divide the bandwidth of the 70% yaw rate gain by... Calculate f p The final result is the arithmetic mean of three test results at the resonant frequency.

[0301] 3.4.8 Minimum Turning Diameter Test

[0302] The car is in the empty state, only with 1 driver, and all wheels are on the ground. According to the needs, the running track display device is installed on the farthest point from the steering center, the closest point, and the center of the wheel tread of the car body. The car is in the lowest forward gear and travels at a low speed, the steering wheel is turned to the limit position and remains unchanged, the track display device is started after stabilization, the vehicle travels a circle, and each measuring point displays a closed motion track on the ground, and then the car is driven out of the measurement area. The diameters of the track circles formed by each measuring point on the ground are measured with a steel tape, which should be measured in two mutually perpendicular directions, and the maximum value should be read by moving left and right; the arithmetic mean of the measured values in the two directions is taken as the test result. The car is measured once to the left and once to the right, and the test results are recorded.

[0303] If the difference between the test results measured in the left and right turning directions is within 0.1 m, the average of the left and right turning test results is taken as the final result of the car, otherwise the larger value of the experimental results measured in the left and right turning directions is taken as the final result.

[0304] 3.4.9 Steering wheel turn number test

[0305] The test car should be parked on the test site, the vehicle is started, the transmission is placed in the neutral position, the brake is released, and the steering wheel is in the middle position. The zero line of each measured variable is recorded. Slowly and evenly turn the force measuring steering wheel to the maximum turning angle to the left, then turn the force measuring steering wheel in the opposite direction (to the right) to the maximum turning angle, and finally turn the force measuring steering wheel to the middle position (to the left). Record the changes of each measured variable during the entire process. At least three tests should be conducted. The average of the results of the three tests is taken as the final result.

[0306] The calculation method of the steering wheel turn number is shown in formula (14).

[0307]

[0308] In the formula: n - steering wheel turn number; δ Lmax - left limit position steering wheel turning angle (°);

[0309] δ Rmax - right limit position steering wheel turning angle (°).

[0310] 4. Overall score calculation of driving control performance

[0311] The selected test indicators are divided into first-level indicators, second-level indicators, and third-level indicators, as shown in Table 6.

[0312] The overall score of the driving control performance is calculated according to the scores and weights of the first-level indicators, and the last digit is retained. The calculation method is shown in the formula.

[0313]

[0314] In the formula, S is the total score of the evaluation of the driving control performance, i is the serial number of the primary index, S i and a i are the score and weight of the primary index with serial number i respectively.

[0315] The score of the primary index is calculated according to the score and weight of the secondary index, and is rounded to two decimal places, and the calculation method is shown in the formula.

[0316]

[0317] In the formula, j is the serial number of the secondary index in the primary index, and ni is the number of the secondary index of the i-th primary index. S ij , b ij are the score and weight of the secondary index with serial number j in the primary index with serial number i respectively.

[0318] The score of the secondary index is calculated according to the score and weight of the tertiary index, and is rounded to two decimal places, and the calculation method is referred to the calculation method of the score of the primary index.

[0319] The score of the tertiary index is calculated by linear interpolation method according to the index limit value corresponding to 60 points and 100 points in Table 6 combined with the index result measured by the test, and is rounded to two decimal places, and if the calculation result is greater than 100 points, it is calculated as 100 points. The weight and index limit value of each level index of the driving control performance of the whole vehicle are shown in Table 6.

[0320] Table 6 Weight and index limit value of each level index of the driving control performance of the whole vehicle

[0321]

[0322] Among them, for the manual transmission vehicle, the indexes "accelerator pedal response time (low speed)" and "start shock" can be calculated as 80 points.

[0323] The above shows and describes the basic principles and main features of the present application and the advantages of the present application, and it is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be realized in other specific forms without departing from the spirit or essential characteristics of the present application;

[0324] Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the essential elements of the claims are intended to be included in the present application.

[0325] Furthermore, it should be understood that although the specification is described in terms of embodiments, not every embodiment includes every feature or implementation described herein. The specification can include implicit combinations of explicitly mentioned features and / or implicit combinations of implicitly mentioned features. Such combinations are also expressly included within the scope of the specification and an embodiment.

Claims

1. A vehicle driving control performance product force test evaluation method based on actual travel conditions, characterized in that it comprises power driving performance test, braking performance test and handling stability test, and after the power driving performance test, braking performance test and handling stability test are respectively carried out, the corresponding test final results are respectively obtained: based on the three test results, the overall score of the vehicle driving control performance is calculated, and the vehicle driving control performance is evaluated according to the overall score of the vehicle driving control performance.

1. The method of power driving test is as follows: The test is carried out on a clean, dry and flat test road, and the vehicle is preheated before the test starts; 1.1 Medium-speed power driving test: The vehicle is accelerated from a stationary state to 30 km / h at 30% throttle opening, and the following indexes are calculated by using the collected test data: the time required for a manual transmission vehicle to accelerate from the start of movement to 30 km / h; the time required for an automatic transmission vehicle to accelerate from the start of stepping on the accelerator pedal to 30 km / h; the time required from the start of stepping on the accelerator pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration during the process from the start of stepping on the accelerator pedal to the peak longitudinal acceleration; the arithmetic mean of the results of each valid index; and the final result of the index; 1.2 Medium-speed power driving test: The vehicle is accelerated from a stationary state to 30 km / h at 30% throttle opening, and the following indexes are calculated by using the collected test data: the time required for a manual transmission vehicle to accelerate from the start of movement to 30 km / h; the time required for an automatic transmission vehicle to accelerate from the start of stepping on the accelerator pedal to 30 km / h; the time required from the start of stepping on the accelerator pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration during the process from the start of stepping on the accelerator pedal to the peak longitudinal acceleration; the arithmetic mean of the results of each valid index; and the final result of the index; 1.3 High-speed power driving test: The vehicle is accelerated from a stationary state to 30 km / h at 30% throttle opening, and the following indexes are calculated by using the collected test data: the time required for a manual transmission vehicle to accelerate from the start of movement to 30 km / h; the time required for an automatic transmission vehicle to accelerate from the start of stepping on the accelerator pedal to 30 km / h; the time required from the start of stepping on the accelerator pedal to 50% of the peak longitudinal acceleration; the maximum slope of the longitudinal acceleration during the process from the start of stepping on the accelerator pedal to the peak longitudinal acceleration; the arithmetic mean of the results of each valid index; and the final result of the index; 2. Braking performance test 2.1 Dry ground braking test: Under full load, the average temperature of the vehicle's hottest axle's service brake is confirmed to be between 65°C and 100°C, the test vehicle is accelerated to above 105 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle remains in D, when the vehicle speed drops to 100±2 km / h, the brake pedal is quickly stepped on until the ABS system starts working or the pedal force reaches 500N, until the vehicle stops; the vehicle speed, braking distance, brake pedal force, deceleration, body pitch angle, braking stability and abnormal conditions during braking are recorded; the braking test is repeated 5 times; 2.2 Wet ground braking test: ​ ​ The test vehicle is accelerated to 85 ± 2 km / h on the starting section, the vehicle enters the test road, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is kept in D range, the emergency brake is applied, the ABS system is activated to act on each wheel, and the brake is maintained until the vehicle stops; the distance traveled by the test vehicle from 80 km / h to 20 km / h is recorded; the first two test data of each test are discarded, and the test vehicle completes at least 6 valid tests; 2.3 Braking stability test At the beginning of the test, the left and right wheels of the vehicle are located on two road surfaces with different adhesion coefficients, and the longitudinal center plane of the vehicle passes through the junction line of the high and low adhesion coefficient road surfaces; emergency braking at an initial speed of 80 km / h, any part of the tire cannot cross the junction line until the vehicle stops, and steering wheel correction is allowed during the test; record the longitudinal speed and yaw rate signals during the test; the left and right sides of the test vehicle complete 3 valid tests respectively; 2.4 Brake pedal linearity test Under light load, the average temperature of the service brake on the hottest axle of the vehicle is confirmed to be 65-100℃, and the brake booster is at normal level; the test vehicle is accelerated to more than 105 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is kept in D range, and when the vehicle speed drops to 100 ± 2 km / h, the brake pedal is slowly pressed until the ABS works, the process requires the deceleration to change linearly, the pressing process is prolonged, and the vehicle speed, deceleration, pedal force, pedal stroke, ABS working condition are recorded; if the brake pedal is pressed too fast, the vehicle speed is above 50 km / h when the ABS works, the test is invalid; the test vehicle completes at least 3 valid tests; 2.5 Light braking test Under light load, the test vehicle is accelerated to more than 65 km / h, the accelerator pedal is released, the manual transmission vehicle is switched to neutral, the automatic transmission vehicle is kept in D range, and when the vehicle speed drops to 60 ± 2 km / h, the brake pedal is quickly pressed and the pedal stroke is kept unchanged, the brake pedal jump time is not more than 0.2 s, until the vehicle stops; when the brake pedal stroke is selected, the vehicle speed in the range of 50-30 km / h and the average deceleration in the range of 1.8-2.2 m / s2 in the test process are met; record the vehicle speed, deceleration and pedal stroke; the test vehicle completes at least 3 valid tests; 3. Handling stability test The test is carried out on dry, flat and clean cement concrete or asphalt pavement, the slope from any direction of the test road should not be greater than 2%, and for steering wheel center zone characteristic test, the slope should not be greater than 1%; Before the test, drive straight at test speed for 10 km or along a radius of 15 m, at a corresponding vehicle speed with lateral acceleration of 3 m / s2, left turn and right turn each once, to warm up the tires; after the tire warming up is completed, the test vehicle enters the test area for various tests; 3.1 Vehicle body roll test On the test site, draw a circle with a radius of not less than 15 m in a conspicuous color; start the vehicle and drive along the drawn circle at the lowest steady speed, accelerating slowly and uniformly, the longitudinal acceleration not exceeding 0.25 m / s2, until the lateral acceleration of the vehicle reaches 6.5 m / s2 or the maximum lateral acceleration that can be reached under the limitation of engine power, or the vehicle becomes unstable, and record the whole process; the test is conducted in two directions, left and right, and the arithmetic mean of the results of 3 left-turn tests and 3 right-turn tests is taken as the final result; 3.2 Obstacle avoidance test Determine the distance between the stakes and the length of each part according to the width of the vehicle, and arrange the stakes on the site; start the test at a pre-set low vehicle speed, gradually increase the vehicle speed until the test driver feels that the vehicle cannot be controlled; record the highest passing speed of obstacle avoidance, and obtain the initial vehicle speed of entering the stake area; take the maximum value of multiple test results as the final result of the highest passing speed of obstacle avoidance; 3.3 Center zone steering characteristic test The initial state of the test is straight-line driving at a constant speed, and the test standard speed is 100 km / h, or the test speed is increased or decreased based on 100 km / h, with an interval of 20 km / h; the steering wheel input is oscillating angular input during the test, and the first input form is sine wave, with a reference frequency of 0.2 Hz, and the frequency deviation is not more than 10%; the steering input during the test is realized by manual or steering robot; When the steering signal is input manually, the test should last at least 40 s; when the steering signal is input by the steering robot, the test should last at least 20 s; Record the steering wheel angle, steering wheel angular velocity, vehicle longitudinal acceleration and vehicle lateral acceleration during the test; Process the test data to obtain lateral acceleration hysteresis and steering wheel angle hysteresis; take the arithmetic mean of the results of 3 tests of each index as the final result; 3.4 Low-speed steering return performance test The test vehicle drives straight along the test section at a speed of 10±1 km / h, and records the zero line of each measured variable; then turn the steering wheel to the limit position, wait for stability and start recording, and then quickly release the steering wheel, and record the vehicle motion process within at least 6 s after releasing the steering wheel; the vehicle speed remains unchanged during the recording time; the test is conducted in two directions, left and right, for 3 times in each direction; Calculate the residual steering wheel angle to obtain the steering wheel angle at 5 s after releasing the steering wheel; Take the arithmetic mean of the results of 3 left-turn tests and 3 right-turn tests of the residual steering wheel angle as the final result; 3.5 High-speed steering return performance test The test vehicle drives along the test section at a constant speed of 100 ± 1 km / h, and the zero line of each measured variable is recorded; then the steering wheel is turned to make the lateral acceleration of the vehicle reach 2 ± 0.2 m / s 2 After being stable and starting to be recorded, the steering wheel is quickly released, and the vehicle movement process within at least 4s after the hand is released is recorded, and the position of the accelerator pedal remains unchanged during the recording time; the test is performed in two directions of left turn and right turn, and each direction is performed 3 times; Process the test data to obtain the yaw rate overshoot; take the arithmetic mean of the results of 3 left-turn tests and 3 right-turn tests of the yaw rate overshoot as the final result; 3.6 Steering wheel angle step input test Before the test, the vehicle is driven at a speed of 100 km / h, and the steady-state lateral acceleration value is 4 m / s 2 , the position of the pre-selected steering wheel angle; the vehicle is driven straight at the test speed, the steering wheel is gently pressed in the input direction to eliminate the free travel of the steering wheel and start recording the zero line of each measured variable, and after 0.2-0.5 s, the steering wheel is turned at a speed of not more than 0.2 s or not less than 200° / s, so that it reaches the pre-selected position and is fixed for a few seconds until the measured variable transitions to a new steady-state value, and the recording is stopped; the vehicle speed remains unchanged during the recording; the test is performed in two directions, left and right turning; the two directions can be alternated, or a one-direction test can be continuously performed, and then another one-direction test is performed; Process the test data to obtain the lateral acceleration response time; take the arithmetic mean of the results of 3 left-turn tests and 3 right-turn tests of the lateral acceleration response time as the final result; 3.7 Sweep frequency test The vehicle is driven straight at a test speed of 100 ± 2 km / h, and the test is started under the condition that the yaw rate is 0 ± 0.5° / s, and a continuous sinusoidal input with gradually increasing frequency is applied to the steering wheel at a predetermined steering wheel angle amplitude, the frequency gradually increases from 0.2 Hz to 3 Hz, and the time is not less than 20 s; the vehicle speed is kept constant during the test; the vehicle is driven around a circle at the selected test speed, and the steering wheel angle when the predetermined steady-state lateral acceleration is reached is taken as the preselected steering wheel angle; Standard steady state lateral acceleration level of 4 m / s 2 ; 3 valid trials were repeated; The test data is processed to obtain the resonance frequency; the arithmetic mean of the results of three times is taken as the final result; 3.8 Minimum turning diameter test The driving trajectory display device is installed on the farthest point from the steering center, the closest point and the center of the wheel tread on the vehicle body; the automobile is in the lowest forward gear and is driven at a low speed, the steering wheel is turned to the limit position and kept unchanged, the trajectory display device is started after stabilization, the vehicle is driven for one round, so that each measuring point displays a closed motion trajectory on the ground respectively, and then the vehicle is driven out of the measurement area; the diameters of the trajectory circles formed by each measuring point on the ground are measured with a ruler, which should be measured in two mutually perpendicular directions, and the maximum value should be read by moving left and right during measurement; the arithmetic mean of the measurement values in the two directions is taken as the test result; the automobile is measured once for left turn and once for right turn, and the test results are recorded; the test data is processed to obtain the final result of the minimum turning diameter; 3.9 Steering wheel turn number test The test automobile should be parked on the test site, the vehicle is started, the transmission is placed in neutral, the brake is released, and the steering wheel is in the middle position, and the zero line of each measured variable is recorded; slowly and uniformly turn the force measuring steering wheel to the maximum steering angle to the left, then turn the force measuring steering wheel to the maximum steering angle in the opposite direction, and finally turn the force measuring steering wheel to the middle position to the left; record the changes of each measured variable during the whole process; at least three tests are performed; the average value of the results of three tests is taken as the final result; 4. Overall score calculation of driving control performance The selected test indicators are divided into primary indicators, secondary indicators and tertiary indicators; the overall score of the driving control performance is calculated according to the scores of the primary indicators and the weights, and the first decimal place is retained, and the calculation method is as follows: In the formula, S is the total score of the evaluation of the driving control performance, i is the serial number of the primary index, S i and a i are the score and weight of the primary index with serial number i, respectively. The score of the primary indicator is calculated according to the scores of the secondary indicators and the weights, and the second decimal place is retained, and the calculation method is shown in formula 2: In the formula, j is the serial number of the secondary index within the primary index, and n i is the number of secondary indexes of the i th primary index; S ij , b ij are the score of the secondary index with serial number j within the primary index with serial number i and the weight of the corresponding secondary index, respectively. The score of the secondary indicator is calculated according to the scores of the tertiary indicators and the weights, and the second decimal place is retained, and the calculation method refers to the calculation method of the score of the primary indicator; The score of the tertiary indicator is calculated by linear interpolation method according to the test results of the indicators and the indicator limits corresponding to 60 points and 100 points, and the second decimal place is retained, and if the calculation result is greater than 100 points, it is calculated as 100 points. The first-level indexes include power driving test, braking performance test and handling stability test; the power driving test includes three second-level indexes, i.e., low-speed power driving, medium-speed power driving and high-speed power driving, and each second-level index includes a plurality of third-level indexes, such as 0-30km / h acceleration time, 40-80km / h acceleration time, 100-140km / h acceleration time, acceleration pedal response time, start-up impact and power system impact; the braking performance test includes five second-level indexes, i.e., braking distance, braking stability, braking pedal linearity, braking response sensitivity and braking comfort, and the corresponding third-level indexes include dry ground braking 100-0km / h braking distance, wet ground braking 80-20km / h braking distance, yaw angular velocity peak value, initial braking pedal force linearity, final braking pedal force linearity, initial braking pedal stroke linearity, slight braking response time, emergency braking response time, braking pitch angle and deceleration change rate; The longitudinal stability test includes six second-level indexes, i.e., steady-state handling stability, transient handling stability, center zone steering characteristic, steering return performance, steering response characteristic and maneuverability, and the corresponding third-level indexes include body roll, obstacle avoidance maximum passing speed, lateral acceleration hysteresis, steering wheel angle hysteresis, residual steering wheel angle, yaw angular velocity overshoot, lateral acceleration response time, resonance frequency, minimum turning diameter and steering wheel turns.

2. The product force test evaluation method for vehicle driving control based on actual travel conditions according to claim 1, characterized in that, The power driving test should be performed on clean, dry and flat concrete or asphalt pavement, the longitudinal slope of the pavement should be no greater than 0.1%, when preheating, all types of vehicles should be driven at 80% of the maximum speed given by the manufacturer for 30 minutes, the pure electric vehicle power battery SOC should be above 80%, the hybrid vehicle power battery SOC value should be displayed full on the instrument, and the preheating driving process should be performed in hybrid mode.

3. The product force test evaluation method for vehicle driving control based on actual travel conditions according to claim 2, characterized in that, During the wet ground braking test, each braking test is controlled in the same test area, and the longitudinal error of the actual driving pavement of each test is no greater than 5m, and the lateral error is no greater than 0.5m.

4. The product force test evaluation method for vehicle driving control based on actual travel conditions according to claim 3, characterized in that, The weights of the power driving test, the braking performance test and the handling stability test are 35%, 30% and 35% respectively, the weights of the low-speed power driving, the medium-speed power driving and the high-speed power driving in the power driving test are 40%, 30% and 30% respectively, the weights of the 0-30km / h acceleration time, the acceleration pedal response time and the start-up impact under the low-speed power driving are 30%, 40% and 30% respectively, the weights of the 40-80km / h acceleration time, the acceleration pedal response time and the power system impact under the medium-speed power driving are 40%, 30% and 30% respectively, and the weights of the 100-140km / h acceleration time, the acceleration pedal response time and the power system impact under the high-speed power driving are 50%, 30% and 20% respectively. The index limit values corresponding to 60 points are as follows: 0-30 km / h acceleration time of 12 s, 40-80 km / h acceleration time of 10 s, 100-140 km / h acceleration time of 15 s, acceleration pedal response time at low speed of 0.85 s, acceleration pedal response time at medium speed of 2 s, acceleration pedal response time at high speed of 2 s, and start shock of 15 m / s 3 ; power system shock at medium speed of 26 m / s 3 ; power system shock at high speed of 22 m / s 3 ; The index limit values corresponding to 100 points are as follows: 0-30km / h acceleration time is 5s, 40-80km / h acceleration time is 4s, 100-140km / h acceleration time is 6s, acceleration pedal response time at low speed is 0.08s, acceleration pedal response time at medium speed is 0.2s, acceleration pedal response time at high speed is 0.2s, and start shock is 1m / s 3 , power system shock at medium speed is 1m / s 3 , power system shock at high speed is 6.5m / s 3 .

5. The product force test evaluation method for vehicle driving control based on actual travel conditions according to claim 4, characterized in that, The weights of the braking distance, braking stability, braking pedal linearity, braking response sensitivity and braking comfort are 30%, 10%, 20%, 20% and 20% respectively; the weights of the dry braking 100-0km / h braking distance and wet braking 80-20km / h braking distance are 70% and 30% respectively, the weight of the peak yaw rate in the braking stability is 100%, the weights of the initial braking pedal force linearity, final braking pedal force linearity and initial braking pedal stroke linearity in the braking pedal linearity are 40%, 20% and 40% respectively, the weights of the slight braking response time and emergency braking response time in the braking response sensitivity are 50% and 50% respectively, and the weights of the braking pitch angle and deceleration change rate in the braking comfort are 60% and 40% respectively; The index limit values corresponding to 60 points are as follows: The dry braking 100-0km / h braking distance, wet braking 80-20km / h braking distance, peak yaw rate, initial braking pedal force linearity, final braking pedal force linearity, initial braking pedal stroke linearity, slight braking response time, emergency braking response time, braking pitch angle and deceleration change rate correspond to 45m, 35m, 10° / s, 0.89, 0.9, 0.8, 0.3s, 0.25s, 2.5° and 30% respectively; The index limit values corresponding to 100 points are as follows: The dry braking 100-0km / h braking distance, wet braking 80-20km / h braking distance, peak yaw rate, initial braking pedal force linearity, final braking pedal force linearity, initial braking pedal stroke linearity, slight braking response time, emergency braking response time, braking pitch angle and deceleration change rate correspond to 38m, 24m, 2° / s, 1, 1, 1, 0.12s, 0.12s, 0.8° and 2% respectively.

6. The product force test evaluation method of the whole vehicle driving control performance based on actual travel conditions according to claim 5, characterized in that, The weights of the steady-state handling stability, transient handling stability, center zone steering characteristic, steering return performance, steering response characteristic and maneuverability are 20%, 15%, 15%, 15%, 20% and 15% respectively; the weight of the body roll in the steady-state handling stability is 100%, the weight of the maximum passing speed of the obstacle avoidance in the transient handling stability is 100%, the weights of the lateral acceleration hysteresis and steering wheel angle hysteresis in the center zone steering characteristic are 50% and 50% respectively, the weights of the residual steering wheel angle and yaw rate overshoot in the steering return performance are 50% and 50% respectively, the weights of the lateral acceleration response time and resonance frequency in the steering response characteristic are 50% and 50% respectively, and the weights of the minimum turning diameter and steering wheel turns in the maneuverability are 60% and 40% respectively; The index limit values corresponding to 60 points are as follows: The body roll, the maximum obstacle avoidance passing speed, the lateral acceleration hysteresis, the steering wheel angle hysteresis, the residual steering wheel angle, the yaw rate overshoot, the lateral acceleration response time, the resonance frequency, the minimum turning diameter, the steering wheel turns are respectively 6° / g, 65km / h, 1.5m / s 2 , 9°, 10°, 60%, 0.35s, 1Hz, 12.6m, 3.4r; The index limit values corresponding to 100 points are as follows: The body roll, the highest passing speed of obstacle avoidance, the lateral acceleration hysteresis, the steering wheel angle hysteresis, the residual steering wheel angle, the yaw rate overshoot, the lateral acceleration response time, the resonance frequency, the minimum turning diameter, the steering wheel turns are respectively 3° / g, 80km / h, 0.2m / s 2 , 1°, 2°, 20%, 0.2s, 1.8Hz, 9.8m, 2.1r.

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