Test method for performing road durability assessment on power assembly on rotary drum test bed

Abstract

The invention discloses a test method for performing road durability assessment on a power assembly on a drum test bench, and belongs to the technical field of automobile tests. The method comprises the following steps: preparation before test; collecting road spectrum information of the endurance test of the test vehicle; according to the collected road spectrum information, compiling a standard and a parameter for simulating durability assessment of the drum test stand; a test vehicle is installed on a drum test bench, and a drum driving robot is installed; performing assessment working condition simulation according to the parameters for durability assessment of the drum test bed compiled in the step S3; and after the examination is completed, the power assembly is decomposed and judged. According to the invention, the endurance quality of the power assembly in different environment states under the whole vehicle condition can be simulated, the pre-judgment range of the test is widened, the performance of the power assembly performance component in different conditions can be known in advance, and the test efficiency is improved. By simulating actual road conditions of the whole vehicle on the rotary drum to perform durability assessment, the limitation of traditional actual road test is overcome.

Description

Technical Field

[0001] The invention relates to a test method for carrying out road durability assessment on a power assembly on a drum test bench, and belongs to the technical field of automobile testing. Background Art

[0002] Traditional actual road durability testing, as a key means of evaluating vehicle performance under various environmental conditions, has long faced many challenges. Such tests usually require vehicles to experience various natural environments and road conditions during long-term and long-distance driving to fully evaluate their durability and reliability. However, this testing method has exposed many shortcomings in actual operation.

[0003] First, changes in the natural environment have a significant impact on actual road durability testing. Temperature fluctuations caused by seasonal changes and slippery roads caused by rain and snow may not only cause test interruptions, but also cause deviations in test results, which cannot accurately reflect the actual performance of the vehicle. This uncertainty not only prolongs the test cycle, but also reduces test efficiency and increases test costs.

[0004] Secondly, there are difficulties in standardization of actual road tests. As actual road conditions are complex and changeable, it is difficult to unify and standardize test conditions, which leads to doubts about the repeatability and reliability of test results. Different test batches may produce completely different results due to differences in road conditions, weather conditions and other factors, making it difficult for test results to be used as a reliable basis for evaluation.

[0005] In addition, actual road testing is also accompanied by higher safety risks. During long driving, the vehicle may lose control due to failure of non-test parts, posing a threat to testers and the surrounding environment. This safety risk not only increases the complexity of the test, but also limits the scope and frequency of the test.

[0006] Finally, considering the impact of production consistency on vehicle durability, traditional actual road durability testing requires at least three vehicles to be tested simultaneously to ensure the accuracy of the test. This not only increases the number and cost of vehicles required for testing, but also multiplies the cost and risk factor of durability assessment. These unfavorable factors have a serious impact on test progress and cost control.

[0007] Therefore, seeking a more efficient, accurate and safer testing method has become an urgent need in the automotive industry. Summary of the invention

[0008] In order to solve the problems existing in the background technology, the present invention provides a test method for performing road durability assessment on a powertrain on a drum test bench.

[0009] To achieve the above object, the present invention adopts the following technical solution: a test method for road durability assessment of a powertrain on a drum test bench, the method comprising the following steps:

[0010] S1: Preparation before the experiment;

[0011] S101: Perform adaptive loading of powertrain;

[0012] S102: Optimizing the adaptive matching between the vehicle status, the powertrain, and the vehicle;

[0013] S103: Installing sensors required for durability assessment on the test vehicle;

[0014] S104: Conduct safety and comprehensive performance inspection on the test vehicle.

[0015] S2: Collecting road spectrum information of the test vehicle durability test;

[0016] The road spectrum information is obtained by transporting the test vehicle to a durability test site and collecting it according to the durability test conditions, or by calculating the engine speed and transmission ratio parameters through the road spectrum information of a similar vehicle model.

[0017] The calculation process is as follows:

[0018] Case 1:

[0019] If the similar parameters between the test vehicle and the similar vehicle model exceed the preset settings, the road spectrum information of the similar vehicle model will be directly applied;

[0020] Case 2:

[0021] If the parameters of the test vehicle and the similar vehicle model do not exceed the preset settings, the difference between the engine speeds is calculated by the difference ratio of the transmission speed ratio. The changed engine speed is used as the road spectrum information of the test vehicle; the specific process of calculating the difference between the engine speeds by the difference ratio of the transmission speed ratio is as follows:

[0022] Step 1: Calculate the wheel speed in a specific gear:

[0023] Wheel speed = engine speed / transmission ratio

[0024] Step 2: Select two different gears, calculate the corresponding wheel speeds respectively, and calculate the difference between the two wheel speeds;

[0025] Step 3: Calculate engine speed difference from wheel speed difference

[0026] Engine speed difference =

[0027] Wheel speed difference × transmission ratio (higher gear) / transmission ratio (lower gear).

[0028] The road spectrum information includes at least the engine speed, engine output power, accelerator pedal opening, transmission clutch state, gear position, output speed and output power of the powertrain in continuous time.

[0029] S3: Prepare the standards and parameters for the simulated durability assessment of the drum test bench based on the collected road spectrum information;

[0030] S301: Determine the resistance to be simulated during the drum test based on the collected road spectrum information

[0031] S302: Confirm the current powertrain operating status through engine speed and gear information

[0032] S303: Confirm the engine load according to the throttle opening

[0033] S304: The vehicle speed is used as a stability indicator to balance the power generated by the vehicle and the power absorbed by the drum, so as to confirm the standards and parameters of the simulated durability assessment of the drum test bench.

[0034] S4: Install the test vehicle on the drum test bench and install the drum driving robot;

[0035] S5: Simulate the test conditions according to the parameters of the drum test bench durability test compiled in S3;

[0036] S501: Divide the test working condition into multiple working condition sections according to the power load, including an urban working condition section, a suburban working condition section, a high-speed working condition section, and an extreme working condition section;

[0037] S502: According to the temperature conditions, each working condition section assessment interval is further subdivided into three temperature assessment intervals of -7°C, 25°C, and 40°C;

[0038] S503: According to the vehicle load, each temperature assessment interval is divided into three load assessment intervals: no load, half load, and full load;

[0039] S504: Combining the above working condition section assessment interval, temperature assessment interval and load assessment interval to form multiple actual assessment working conditions;

[0040] S505: According to the positioning requirements of the vehicle model usage characteristics, select the number of repetitions of each actual test condition to perform durability test;

[0041] S506: After completing the assessment of all actual assessment conditions, corresponding actual assessment conditions are added according to the actual state of the powertrain to conduct further durability testing.

[0042] S6: After the assessment is completed, the powertrain is analyzed and judged.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. The present invention can simulate the durability performance of the powertrain under different environmental conditions under vehicle conditions, broaden the scope of test prediction, and understand the performance of powertrain performance components under different conditions in advance, thereby improving test efficiency. In addition, by simulating the actual vehicle road conditions on the drum for durability assessment, the limitations of traditional actual road tests are overcome, the product development cycle is shortened, and automobile manufacturers can bring high-quality products to market faster.

[0045] 2. The present invention uses a specific test platform vehicle to perform a whole vehicle durability simulation assessment, which reduces the probability of risks occurring during the durability assessment process and ensures the safety and reliability of the test; uses a driving robot to drive the whole vehicle, avoiding test data deviations or misoperation caused by driver fatigue, ensuring the consistency and comparability of each test, and providing reliable data support for the continuous improvement of product quality. DETAILED DESCRIPTION

[0046] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0047] The drum test bench is a device that can simulate the driving state of a vehicle under laboratory conditions. It can provide a stable and repeatable test environment, including environmental conditions such as road conditions, light and temperature, and is not affected by external weather and road conditions. By precisely controlling the speed of the drum, acceleration and deceleration mode, slope simulation and other factors, the load conditions of the vehicle under different working conditions can be more realistically reproduced, thereby achieving a comprehensive evaluation of the powertrain system. In addition, using advanced sensor technology and data processing algorithms, various performance indicators of the vehicle can be monitored in real time during the drum test, such as engine output power, gearbox shifting smoothness, brake system response time, etc., thereby improving the accuracy of the test results.

[0048] A test method for testing the road durability of a powertrain on a drum test bench of the present invention comprises the following steps:

[0049] S1: Preparation before the experiment;

[0050] S101: selecting a corresponding test vehicle according to the powertrain to be tested, mounting the powertrain to be tested on the whole vehicle driving platform of the corresponding test vehicle, and performing powertrain adaptive mounting;

[0051] S102: Optimize the adaptive matching between the vehicle status and the powertrain and the vehicle to ensure that the test vehicle can successfully complete the WLTC working condition test and meet the emission standards of the corresponding vehicle model;

[0052] S103: Install sensors required for durability assessment on the test vehicle, including transmission oil pressure sensor, exhaust temperature sensor, output shaft torque sensor, etc.;

[0053] S104: Conduct safety and comprehensive performance inspection on the test vehicle.

[0054] S2: Collecting road spectrum information of the test vehicle durability test;

[0055] To ensure the accuracy of the test, the road spectrum information is obtained by transporting the test vehicle to a durability test site and collecting it according to the durability test conditions, or by calculating the engine speed and transmission ratio parameters through the road spectrum information of other similar models in the past.

[0056] The calculation process is as follows:

[0057] Case 1:

[0058] If the parameters similar to the test vehicle and the similar model exceed the preset settings (for example, the engine is a 1.6L engine, the transmission has a main reduction ratio between 3.414-3.722, the speed ratios of each gear are not much different, and the vehicle test mass is between 1.5t-1.7t), the road spectrum information of the similar model will be directly used;

[0059] Case 2:

[0060] If the parameters of the test vehicle and the similar vehicle model do not exceed the preset settings, the difference between the engine speeds is calculated by the difference ratio of the transmission speed ratio. The changed engine speed is used as the road spectrum information of the test vehicle; the specific process of calculating the difference between the engine speeds by the difference ratio of the transmission speed ratio is as follows:

[0061] Step 1: Calculate the wheel speed in a specific gear:

[0062] Wheel speed = engine speed / transmission ratio

[0063] For a given transmission, each gear has a fixed speed ratio, which can usually be found in the vehicle's technical data sheet or obtained by consulting the relevant information of the transmission.

[0064] Step 2: Select two different gears, calculate the corresponding wheel speeds respectively, and calculate the difference between the two wheel speeds;

[0065] Step 3: Calculate engine speed difference from wheel speed difference

[0066] Engine speed difference =

[0067] Wheel speed difference × transmission ratio (higher gear) / transmission ratio (lower gear)

[0068] The difference in vehicle test quality is an indicator that affects the vehicle's acceleration performance. The difference in acceleration can be calculated based on the well-known formula F=Ma, and the acceleration time can be appropriately increased in the drum test.

[0069] The road spectrum information includes at least the engine speed, engine output power, accelerator pedal opening, transmission clutch state, gear position, output speed and output power of the powertrain in continuous time.

[0070] S3: Prepare the standards and parameters for the simulated durability assessment of the drum test bench based on the collected road spectrum information;

[0071] S301: Determine the resistance to be simulated during the drum test based on the collected road spectrum information

[0072] S302: Confirm the current powertrain operating status through engine speed and gear information

[0073] S303: Confirm the engine load according to the throttle opening

[0074] S304: The vehicle speed is used as a stability indicator to balance the power generated by the vehicle and the power absorbed by the drum, so as to confirm the standards and parameters of the simulated durability assessment of the drum test bench.

[0075] S4: Install the test vehicle on the drum test bench and install a drum driving robot to operate the accelerator pedal, brake pedal and shift handle for durability assessment to improve efficiency, reduce personnel safety risks and improve test accuracy;

[0076] S5: Simulate the test conditions according to the parameters of the drum test bench durability test compiled in S3;

[0077] S501: Divide the test working condition into multiple working condition sections according to the power load, including an urban working condition section, a suburban working condition section, a high-speed working condition section, and an extreme working condition section;

[0078] S502: According to the temperature conditions, each working condition section assessment interval is further subdivided into three temperature assessment intervals of -7°C, 25°C, and 40°C;

[0079] S503: According to the vehicle load, each temperature assessment interval is divided into three load assessment intervals: no load, half load, and full load;

[0080] S504: Combining the above working condition section assessment interval, temperature assessment interval and load assessment interval to form multiple actual assessment working conditions;

[0081] S505: According to the positioning requirements of the vehicle model usage characteristics, select the number of repetitions of each actual test condition to perform durability test;

[0082] S506: After completing the assessment of all actual assessment conditions, corresponding actual assessment conditions are added according to the actual state of the powertrain to conduct further durability testing.

[0083] S6: After the assessment is completed, the powertrain is analyzed and judged.

[0084] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalents of the claims be included in the present invention.

[0085] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A test method for road durability assessment of a powertrain on a drum test bench, characterized in that: The method comprises the following steps: S1: Preparation before the experiment; S2: Collecting road spectrum information of the test vehicle durability test; S3: Prepare the standards and parameters for the simulated durability assessment of the drum test bench based on the collected road spectrum information; S4: Install the test vehicle on the drum test bench and install the drum driving robot; S5: Simulate the test conditions according to the parameters of the drum test bench durability test compiled in S3; S6: After the assessment is completed, the powertrain is analyzed and judged.

2. The method for testing the road durability of a powertrain on a drum test bench according to claim 1, characterized in that: The S1 comprises the following steps: S101: Perform powertrain adaptive loading; S102: Optimizing the adaptive matching between the vehicle status, the powertrain, and the vehicle; S103: Installing sensors required for durability assessment on the test vehicle; S104: Conduct safety and comprehensive performance inspection on the test vehicle.

3. The test method for road durability assessment of a powertrain on a drum test bench according to claim 2, characterized in that: The road spectrum information described in S2 is obtained by transporting the test vehicle to a durability test site and collecting the information according to the durability test conditions.

4. The test method for road durability assessment of a powertrain on a drum test bench according to claim 2, characterized in that: The road pattern information in S2 is obtained by calculating the road pattern information of a similar vehicle model through engine speed and transmission ratio parameters.

5. The test method for road durability assessment of a powertrain on a drum test bench according to claim 4, characterized in that: The process of calculating the road spectrum information is as follows: Case 1: If the similar parameters between the test vehicle and the similar vehicle model exceed the preset settings, the road spectrum information of the similar vehicle model will be directly applied; Case 2: If the similar parameters of the test vehicle and the similar vehicle model do not exceed the preset settings, the difference between the engine speeds is calculated by the difference ratio of the transmission speed ratio, and the changed engine speed is used as the road spectrum information of the test vehicle; the specific process of calculating the difference between the engine speeds by the difference ratio of the transmission speed ratio is as follows: Step 1: Calculate the wheel speed in a specific gear: Wheel speed = engine speed / transmission ratio Step 2: Select two different gears, calculate the corresponding wheel speeds respectively, and calculate the difference between the two wheel speeds; Step 3: Calculate engine speed difference from wheel speed difference Engine speed difference = Wheel speed difference × transmission ratio (higher gear) / transmission ratio (lower gear).

6. A test method for road durability assessment of a powertrain on a drum test bench according to claim 3 or 4, characterized in that: The road spectrum information includes at least the engine speed, engine output power, accelerator pedal opening, transmission clutch state, gear position, output speed and output power of the powertrain in continuous time.

7. The test method for road durability assessment of a powertrain on a drum test bench according to claim 1, characterized in that: The S3 comprises the following steps: S301: Determine the resistance to be simulated during the drum test based on the collected road spectrum information S302: Confirm the current powertrain operating status through engine speed and gear information S303: Confirm the engine load according to the throttle opening S304: The vehicle speed is used as a stability indicator to balance the power generated by the vehicle and the power absorbed by the drum, so as to confirm the standards and parameters of the simulated durability assessment of the drum test bench.

8. The test method for road durability assessment of a powertrain on a drum test bench according to claim 1, characterized in that: The S5 comprises the following steps: S501: Divide the test working condition into multiple working condition sections according to the power load, including an urban working condition section, a suburban working condition section, a high-speed working condition section, and an extreme working condition section; S502: According to the temperature conditions, each working condition section assessment interval is further subdivided into three temperature assessment intervals of -7°C, 25°C, and 40°C; S503: According to the vehicle load, each temperature assessment interval is divided into three load assessment intervals: no load, half load, and full load; S504: Combining the above working condition section assessment interval, temperature assessment interval and load assessment interval to form multiple actual assessment working conditions; S505: According to the positioning requirements of the vehicle model usage characteristics, select the number of repetitions of each actual test condition to perform durability test; S506: After completing the assessment of all actual assessment conditions, corresponding actual assessment conditions are added according to the actual state of the powertrain to conduct further durability testing.