On-road driving test evaluation method, vehicle test system, and on-road driving test evaluation program

Abstract

To make efficient motor vehicle development conforming to a road driving test by front loading evaluation of a road driving test complying with regulations such as RDE.SOLUTION: A road driving test evaluation method performs a bench test on a test piece that is an actual vehicle or a part thereof to evaluate a road driving test complying with regulations. The method includes: a virtual evaluation step of simulating a road driving test by using a driving environment model obtained by modeling a driving environment, a driving mode model obtained by modeling a driving mode, and a vehicle model obtained by modeling the actual vehicle; a bench test evaluation step of combining a part or all of the actual vehicle, a part or all of the vehicle model, a part or all of the driving environment model, and a part or all of the driving mode model to perform a bench test on part or all of the actual vehicle, thereby simulating the road driving test; and a road driving test evaluation step of executing the road driving test on the actual vehicle in an actual driving environment.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a road driving test evaluation method and a vehicle test system for evaluating a road driving test that complies with regulations such as an RDE (Real Driving Emission) test.

Background Art

[0002] In recent years, road driving tests that comply with regulations such as the RDE test have been conducted. And, in order to develop automobiles that comply with this road driving test, by simulating the road driving test using a bench test device such as an engine test bench, a drive system test bench, or a vehicle test bench, efforts have been made to improve the efficiency of developing automobiles that comply with the road driving test.

[0003] By the way, in order to simulate a road driving test using the above bench test device, settings such as a route model that complies with regulations, a driving environment model, and a driving mode model (driver model) are required. For this reason, a route model, a driving environment model, and a driver model are created using commercially available model creation software. As shown in Patent Document 1, in a road exhaust gas certification test, in order to easily perform driving that satisfies the test conditions, a driving operation style including at least any one of an accelerator operation, a brake operation, or a shift operation for satisfying the test conditions is considered to be presented to the driver.

[0004] However, in conventional model creation software, since a plurality of input parameters for creating a model are not optimized for creating a model for a road driving test, to a large extent, it depends on the experience and skills of the model creator as to which parameters should be set to what values to obtain a model that complies with the road driving test, and a lot of labor is required to create an optimal model that complies with the road driving test.

[0005] In addition, in the above description, the on-road driving test is only simulated using a bench test apparatus such as an engine test bench, a drive train test bench, or a vehicle test bench, and the test results of these tests and the test results of the actual on-road driving test are not comprehensively judged.

Prior Art Document

Patent Document

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, the present invention has been made to solve the above problems, and its main problem is to improve the efficiency of automobile development in accordance with on-road driving tests by front-loading the evaluation of on-road driving tests that comply with regulations such as RDE tests.

Means for Solving the Problems

[0008] That is, the on-road driving test evaluation method according to the present invention is an on-road driving test evaluation method for evaluating an on-road driving test that complies with regulations by bench-testing a test specimen that is an actual vehicle or a part thereof, and includes a virtual evaluation step of simulating the on-road driving test using a driving environment model that models a driving environment, a driving mode model that models a driving mode, and a vehicle model that models the actual vehicle, and a bench test evaluation step of simulating the on-road driving test by combining a part or all of the actual vehicle, a part or all of the vehicle model, a part or all of the driving environment model, and a part or all of the driving mode model and bench-testing a part or all of the actual vehicle, and an on-road driving test evaluation step of performing the on-road driving test on the actual vehicle in an actual driving environment.

[0009] In such a case, since at least three steps, namely the virtual evaluation step, the bench test evaluation step, and the road test evaluation step, are performed, the validity of the driving environment model, the driving mode model, and the vehicle model used in the virtual evaluation step can be verified using the evaluation results of the bench test evaluation step. Thus, a model compliant with the road test can be created regardless of the experience and skills of the model creator. Also, by performing the virtual evaluation step and the bench test evaluation step, the evaluation of the road test compliant with regulations such as the RDE test can be front-loaded. As a result, the efficiency of vehicle development compliant with the road test can be improved. In addition, by performing the road test evaluation step in addition to the virtual evaluation step and the bench test evaluation step, the validity of the virtual evaluation step and the bench test evaluation step can also be verified.

[0010] It is desirable that the bench test evaluation step includes a first bench test evaluation step that simulates the road test by combining a part including the engine of the actual vehicle, a part or all of the vehicle model, a part or all of the driving environment model, and a part or all of the driving mode model, and performing a bench test on the part including the engine of the actual vehicle.

[0011] Furthermore, in order to further improve the efficiency of vehicle development compliant with the road test, it is desirable that the bench test evaluation step further includes a second bench test evaluation step that simulates the road test by combining the actual vehicle, a part or all of the driving environment model, and a part or all of the driving mode model, and performing a bench test on the actual vehicle between the first bench test evaluation step and the road test evaluation step.

[0012] As a specific embodiment of the present invention, it is desirable to include at least one step among a first comparison step of comparing some evaluation results including the engine of the actual vehicle in the first bench test evaluation step with the evaluation results of the vehicle model in the virtual evaluation step, a second comparison step of comparing the evaluation results of the actual vehicle in the second bench test evaluation step with some evaluation results including the engine of the vehicle in the first bench test evaluation step, and a third comparison step of comparing the evaluation results of the actual vehicle in the road running test evaluation step with the evaluation results of the actual vehicle in the second bench test evaluation step.

[0013] In order to front-load the evaluation of the road running test compliant with regulations such as the RDE test by utilizing the evaluation results, a first feedback step of feeding back to the virtual evaluation step so that the evaluation results of the vehicle model in the virtual evaluation step match some evaluation results including the engine of the actual vehicle in the first bench test evaluation step, a second feedback step of feeding back to the first bench test evaluation step so that some evaluation results including the engine of the actual vehicle in the first bench test evaluation step match the evaluation results of the actual vehicle in the second bench test evaluation step, and a third feedback step of feeding back to the second bench test evaluation step so that the evaluation results of the actual vehicle in the second bench test evaluation step match the evaluation results of the actual vehicle in the road running test evaluation step. It is desirable to include at least one step.

[0014] In the road running test evaluation method of the present invention, as a specific embodiment for performing quantitative evaluation, it is desirable that the road running test evaluation step is performed using an in-vehicle exhaust gas analyzer, and the second bench test evaluation step is performed using a stationary or in-vehicle exhaust gas analyzer.

[0015] The detection efficiency of the solid particle number measurement unit in the stationary exhaust gas analyzer is different from that of the solid particle number measurement unit in the in-vehicle exhaust gas analyzer. Therefore, In order to accurately front-load the evaluation of the on-road driving test that complies with regulations such as the RDE test, it is conceivable to use an in-vehicle exhaust gas analyzer in the second bench test evaluation step. However, it is troublesome to move the in-vehicle exhaust gas analyzer to the test bench (laboratory) for testing. To solve this problem, the second bench test evaluation step is performed using a stationary exhaust gas analyzer, and it is desirable that the detection efficiency of the solid particle number measurement unit of the stationary exhaust gas analyzer is the same as that of the solid particle number measurement unit of the in-vehicle exhaust gas analyzer.

[0016] Also, in the on-road driving test evaluation method of the present invention, as a specific embodiment for performing quantitative evaluation, the exhaust gas test results in at least any two of the first bench test evaluation step, the second bench test evaluation step, and the on-road driving test evaluation step are compared, and the measurement components used for the comparison of the exhaust gas test results are carbon dioxide (CO2), carbon monoxide (CO), particulate matter (PM), particulate matter number (PN), ammonia (NH3), nitrous oxide (N2O), nitrogen oxides (NOx), or total hydrocarbons (THC), and it is desirable that at least one of them is used.

[0017] As the driving mode of the bench test evaluation step, it is desirable that the bench test evaluation step drives a part or all of the actual vehicle based on the driving mode model used in the virtual evaluation step.

[0018] As the driving mode in the second bench test evaluation step, based on the driving mode reproduced in the first bench test evaluation step, the driving mode in the second bench test evaluation step is reproduced. In the second bench test evaluation step, it is desirable that the driver drives the actual vehicle or the automatic driving robot drives the actual vehicle based on the driving mode model used in the first bench test evaluation step.

[0019] As the realization mode of the driving environment model in the first bench test evaluation step or the second bench test evaluation step, it is desirable that the driving environment model in the first bench test evaluation step or the second bench test evaluation step is reproduced by connecting pipes to the intake side and the exhaust side of the engine and controlling the pressure through the pipes.

[0020] As a specific implementation mode of the driving mode model, in the virtual evaluation step, the combination of parameters constituting the driving mode model is preferably associated with at least one of RPA (Relative Positive Acceleration) or vapos_

[95] (Relative Positive Acceleration 95th percentile) so as to conform to the on-road driving test compliant with regulations.

[0021] As the test specimen, those having an advanced driver assistance system (ADAS) are also conceivable. In the test specimen having this ADAS, in order to front-load the evaluation of the on-road driving test compliant with regulations such as the RDE test, in addition to the driving environment model, the driving mode model and the vehicle model, the virtual evaluation step preferably uses at least one of a sensor model obtained by modeling the sensors required for the ADAS or an ADAS model obtained by quantifying the ADAS to simulate the on-road driving test.

[0022] As the test subject, a hybrid vehicle in which an engine and a battery operate in cooperation can be considered. In this hybrid vehicle, in order to front-load the evaluation of a road running test conforming to regulations such as an RDE test, in addition to the driving environment model, the driving pattern model, and the vehicle model, the virtual evaluation step preferably simulates the road running test using a battery model that models the battery.

[0023] Moreover, a vehicle test system according to the present invention is a vehicle test system for evaluating a road running test conforming to regulations by conducting a bench test on a test subject that is an actual vehicle or a part thereof, and includes a simulation device that simulates the road running test using a driving environment model that models a driving environment, a driving pattern model that models a driving pattern, and a vehicle model that models the actual vehicle, and a part including the engine of the actual vehicle, a part or all of the vehicle model, a part or all of the driving environment model, and a part or all of the driving pattern model are combined to simulate the road running test by conducting a bench test on a part including the engine of the actual vehicle. A first bench test device, and a second bench test device that simulates the road running test by combining the actual vehicle, a part or all of the driving environment model, and a part or all of the driving pattern model and conducting a bench test on the actual vehicle.

[0024] Furthermore, a program for evaluating a road running test according to the present invention is a program for evaluating a road running test conforming to regulations by conducting a bench test on a test subject that is an actual vehicle or a part thereof. The program causes a computer to simulate the road running test using a driving environment model that models a driving environment, a driving pattern model that models a driving pattern, and a vehicle model that models the actual vehicle, and combines a part or all of the actual vehicle, a part or all of the vehicle model, a part or all of the driving environment model, and a part or all of the driving pattern model, and causes a part or all of the actual vehicle to be bench-tested by a bench test device to simulate the road running test.

Advantages of the Invention

[0025] According to the present invention described above, by front-loading the evaluation of a road driving test that complies with regulations such as the RDE test, it is possible to improve the efficiency of automobile development based on the road driving test.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0027] Hereinafter, a vehicle test system and a road driving test evaluation method according to an embodiment of the present invention will be described with reference to the drawings.

[0028] <Device Configuration of Vehicle Test System> The vehicle test system 100 of the present embodiment evaluates a road driving test that complies with regulations by bench-testing a test specimen that is an actual vehicle or a part thereof. Here, the road driving test that complies with regulations is, for example, the road driving emission gas test (RDE (Real Driving Emission) test) introduced in various countries such as Europe.

[0029] Specifically, as shown in FIG. 1, the vehicle test system 100 includes a simulation device 2 that simulates a road driving test, a first bench test device 3 that simulates a road driving test by bench-testing a part including the engine of an actual vehicle, a second bench test device 4 that simulates a road driving test by bench-testing an actual vehicle, and a host management device 5 that integrally manages the simulation device 2, the first bench test device 3, and the second bench test device 4.

[0030] The simulation device 2 simulates a road driving test using a driving environment model that models a driving environment, a driving mode model that models a driving mode, and a vehicle model that models an actual vehicle, and is a computer including a CPU, an internal memory, an input / output interface, input means such as a keyboard, output means such as a display, and communication means.

[0031] This simulation device 2 includes a relational data storage unit 21 that stores each model, and a simulation unit 22 that simulates driving in accordance with an RDE test.

[0032] The driving environment model stored in the relational data storage unit 21 is a model that quantifies a driving route, the road resistance of the driving route, signs, temperature and humidity, the elevation of the driving route, the degree of traffic congestion (traffic volume) of the driving route, and the like.

[0033] Further, the driving mode model stored in the relational data storage unit 21 is a model that quantifies Dynamics (workload), Energy Efficiency (energy efficiency), and Nervousness (tension).

[0034] Specifically, the driving mode model includes, for example, the following parameters listed in the software "CarMaker" of IPG Automotive Co., Ltd. Dynamics parameters: Crusing speed [km / h], Corner cutting coefficient [-], dt Change of pedals [s], Max. Long Acceleration [m / s 2 , Max. Long Dceleration [m / s 2 , Max. Lat Acceleration [m / s 2 , Exponent of g-g Diagram [-], Time of Shifting [s], Engine Speeds min / mas [rpm], Engine Speeds idle up / acc. Down [rpm], Long Smooth Throttle Limit [-] Energy Efficiency parameters: Min. dt Accel / Decel [s], Long Drag Torque Braking [-], Long Drive Cycle Tol [-], Long drive Cycle Coef [-] Nervousness parameters: Long SDV Random [-], Long SDV Random f [-]

[0035] Furthermore, the vehicle model stored in the related data storage unit 21 has at least an engine model that digitizes the engine, and models vehicle information such as the type of actual vehicle (truck, passenger car, etc.), weight, transmission type (MT, AT, CVT, etc.), tire diameter, gear ratio, engine characteristics (relationship between throttle opening and rotational speed and output torque, etc.), control characteristics of the ECU (relationship between accelerator opening and throttle opening, etc.), control characteristics of the TCU (conditions for changing the gear ratio and its timing, etc.), or control characteristics of the BCU (distribution of braking force to each wheel, etc.). These models are stored in the related data storage unit 21 in advance.

[0036] The simulation unit 22 simulates driving in which the test results of emissions in the MAW (Moving Averaging Window) method or the Power Bining method fall within a predetermined range as a road driving test compliant with the RDE test, based on each model stored in the related data storage unit 21.

[0037] Also, in the above simulation, the simulation unit 22 uses a plurality of driving characteristics included in the driving mode model as input parameters to obtain RPA (Relative Positive Acceleration) or vapos_

[95] (Relative Positive Acceleration 95 th percentile) when driving in accordance with the RDE test.

[0038] Here, the simulation unit 22 creates combinations of input parameters of a plurality of driving characteristics by the design of experiments (DoE (Design of experiments)), and executes a simulation of a road driving test compliant with the RDE test using the created combination patterns. Then, the simulation unit 22 obtains RPA (Relative Positive Acceleration) or vapos_

[95] (Relative Positive Acceleration 95 th percentile) from the simulation results.

[0039] Furthermore, the simulation unit stores in the related data storage unit 21 by associating the combination pattern of input parameters with the corresponding RPA or vapos_

[95] . Thereby, by selecting RPA or vapos_

[95] , the combination pattern (driving mode model) of input parameters corresponding to the RPA or vapos_

[95] can be determined. This determined driving mode model is transmitted to the first bench test device 3 or the second bench test device 4 described later and used in the tests using each test device 3, 4.

[0040] As shown in FIG. 3, the first bench test apparatus 3 combines a part including the engine E of the actual vehicle, a vehicle model excluding the part including the engine E, and a driving environment model and / or a driving mode model, and bench-tests a part including the engine E of the actual vehicle to simulate a road driving test. Here, the first bench test apparatus 3 is an engine bench (engine dynamometer) with the engine E as the test specimen. Note that the part including the engine of the actual vehicle may be a drive system including a transmission in addition to the engine, and in this case, the bench test apparatus is configured using a dynamometer connected to the drive shaft of the drive system.

[0041] This first bench test apparatus 3 includes an engine dynamometer 31 that applies a load to the engine E, a control device 32 that controls the engine dynamometer 31, and a stationary exhaust gas analyzer 33 that analyzes the exhaust gas discharged from the engine E, for example.

[0042] The control device 32 controls the engine dynamometer 31 based on a vehicle model excluding a part including the engine, and a driving environment model and a driving mode model. Further, the control device 32 operates the engine E based on the driving mode model generated by the simulation unit 22.

[0043] Furthermore, in order to reproduce the driving environment, pipes are connected to the intake side and the exhaust side of the engine in the first bench test apparatus 3, and a portable pressure adjustment device (environment reproduction device) 34 that adjusts the pressure inside the engine through the pipes is provided. This pressure adjustment device 34 is controlled by the control device 32 based on the driving environment model. Note that the first bench test apparatus 3 may be installed in an environmental test chamber capable of adjusting temperature, humidity, or pressure to reproduce the driving environment.

[0044] The exhaust gas analyzer 33 analyzes at least one of carbon dioxide (CO2), carbon monoxide (CO), particulate matter (PM), particulate number (PN), ammonia (NH3), nitrous oxide (N2O), nitrogen oxides (NOx), or total hydrocarbons (THC) in the exhaust gas discharged from the engine E. The exhaust gas measurement results measured by this exhaust gas analyzer 33 are transmitted to the upper management device 5 or the control device 32.

[0045] As shown in FIG. 4, the second bench test device 4 simulates a road running test by combining the actual vehicle V with a running environment model and a driving mode model and conducting a bench test on the actual vehicle V.

[0046] This second bench test device 4 includes a chassis dynamometer (chassis bench) 41 on which the actual vehicle V is mounted, a control device 42 that controls the chassis dynamometer 41, and an exhaust gas analyzer 43, such as a stationary type or in-vehicle type, that analyzes the exhaust gas discharged from the engine E.

[0047] The control device 42 controls the chassis dynamometer 41 based on the running environment model and the driving mode model. Further, the control device 42 controls the autonomous driving robot 44 based on the driving mode model used in the first bench test device 3, and thereby the autonomous driving robot 44 drives the actual vehicle V.

[0048] Furthermore, in order to reproduce the running environment, pipes are connected to the intake side and the exhaust side of the engine E in the second bench test device 4, and a portable pressure adjusting device (environment reproduction device) 45, for example, that adjusts the pressure inside the engine through the pipes is provided. This pressure adjusting device 45 is controlled by the control device 42 based on the running environment model. Note that the pressure adjusting device 45 of the second bench test device 4 and the pressure adjusting device 34 of the first bench test device 3 may be shared with each other, or may be provided separately. Note that the second bench test device 4 may be installed in an environmental test chamber capable of adjusting temperature, humidity, or pressure to reproduce the running environment.

[0049] The exhaust gas analyzer 43 analyzes at least one of carbon dioxide (CO2), carbon monoxide (CO), particulate matter (PM), particulate matter number (PN), ammonia (NH3), nitrous oxide (N2O), nitrogen oxides (NOx), or total hydrocarbon (THC) in the exhaust gas discharged from the engine. The exhaust gas measurement results measured by this exhaust gas analyzer 43 are transmitted to the upper management device 5 or the control device 32. Note that the exhaust gas analyzer 43 of the second bench test device 4 and the exhaust gas analyzer 33 of the first bench test device 3 may be shared with each other, or may be provided separately.

[0050] As shown in FIG. 2 and the like, the upper management device 5 performs scheduling of the following road running test method and management of various data by transmitting and receiving data to and from the simulation device 2, the first bench test device 3, and the second bench test device 4. It is a computer equipped with a CPU, an internal memory, an input / output interface, input means such as a keyboard, output means such as a display, communication means, and the like. The upper management device 5 stores the simulation evaluation result obtained by the simulation device 2, the first bench test evaluation result obtained by the first bench test device 3, the second bench test evaluation result obtained by the second bench test device 4, and the road running test evaluation result obtained by the road running test. Note that the road running test evaluation result is stored in the upper management device 5 via communication or a recording medium.

[0051] <Road Running Test Evaluation Method> Next, a road running test evaluation method using the vehicle test system of the present embodiment will be described. As shown in Fig. 5, the on-road driving test evaluation method of this embodiment includes a virtual evaluation step (RDE + VIRTUAL) for simulating the on-road driving test, a first bench test evaluation step (RDE + POWER) for simulating the on-road driving test by bench-testing a part including the engine of the actual vehicle, a second bench test evaluation step (RDE + CHASSIS) for simulating the on-road driving test by bench-testing the actual vehicle, and an on-road driving test evaluation step (RDE + ROAD) for conducting the on-road driving test on the actual vehicle in the real driving environment.

[0052] The virtual evaluation step is implemented by the simulation unit 22 of the simulation device 2, and uses a driving environment model, a driving mode model, and a vehicle model to simulate an on-road driving test that complies with regulations. In this virtual evaluation step, combinations of input parameters of multiple driving characteristics are created, and using the created combination patterns, a simulation of the on-road driving test compliant with the RDE test is executed. Then, from the simulation results, RPA (Relative Positive Acceleration) or vapos_

[95] (Relative Positive Acceleration 95 th percentile) is obtained and stored in the relationship data storage unit 21 corresponding to the combination pattern of the input parameters. Thereby, by selecting RPA or vapos_

[95] , the combination pattern (driving mode model) of the input parameters corresponding to the RPA or vapos_

[95] can be determined.

[0053] The first bench test evaluation step is implemented using the first bench test device 3. Using the simulation results obtained by the simulation device 2, the engine E is operated and the engine dynamometer 31 is controlled, and the exhaust gas discharged at that time is analyzed by the exhaust gas analyzer 33.

[0054] Here, in the first bench test evaluation step, by selecting RPA or vapos_

[95] , a combination pattern (operation mode model) of input parameters corresponding to the RPA or vapos_

[95] is determined, and based on the determined operation mode model, the engine E is operated. Then, in this first bench test evaluation step, it is evaluated whether the test result of emissions in the MAW method or the Power Bining method falls within a predetermined range. Additionally, in the first bench test evaluation step, the emission amount of the measured components in the exhaust gas measured by the exhaust gas analyzer 33 may be evaluated.

[0055] The second bench test evaluation step is carried out using the second bench test apparatus 4. Based on the operation mode model used in the first bench test apparatus 3, the actual vehicle V is operated and the chassis dynamometer 41 is controlled to analyze the exhaust gas discharged at that time by the exhaust gas analyzer 43. Then, in this second bench test evaluation step, it is evaluated whether the test result of emissions in the MAW method or the Power Bining method falls within a predetermined range. Additionally, in the second bench test evaluation step, the emission amount of the measured components in the exhaust gas measured by the exhaust gas analyzer 43 may be evaluated.

[0056] The on-road driving test evaluation step is implemented by conducting an on-road driving test on the actual vehicle V in an actual driving environment (i.e., an actual road), and analyzing the exhaust gas emitted from the actual vehicle V driving on the actual road using an in-vehicle exhaust gas analyzer. Then, in this on-road driving test evaluation step, it is evaluated whether the test results of emissions in the MAW method or the Power Bining method fall within a predetermined range. In addition, in the on-road driving test evaluation step, the emission amount of the measured components in the exhaust gas measured by the in-vehicle exhaust gas analyzer may be evaluated. Note that the in-vehicle exhaust gas analyzer analyzes at least one of carbon dioxide (CO2), carbon monoxide (CO), particulate matter (PM), particulate number (PN), ammonia (NH3), nitrous oxide (N2O), nitrogen oxides (NOx), or total hydrocarbon (THC) in the exhaust gas emitted from the engine. The exhaust gas measurement results measured by this exhaust gas analyzer 43 are transmitted to the upper management device 5.

[0057] The evaluation results obtained in each of the above evaluation steps can be compared with each other. Specifically, a first comparison step can be performed to compare some of the evaluation results including the engine E of the actual vehicle V in the first bench test evaluation step with the evaluation results of the vehicle model in the virtual evaluation step. Then, based on the comparison result of this first comparison step, a first feedback step can be performed to feedback, for example, by changing the vehicle model in the virtual evaluation step so that the evaluation results of the vehicle model in the virtual evaluation step match some of the evaluation results including the engine of the actual vehicle in the first bench test evaluation step.

[0058] In addition, a second comparison step can be performed to compare the evaluation result of the actual vehicle in the second bench test evaluation step with some of the evaluation results including the vehicle engine in the first bench test evaluation step. Then, a second feedback step can be performed to provide feedback, for example, by changing the vehicle model in the first bench test evaluation step so that some of the evaluation results including the vehicle engine in the first bench test evaluation step match the evaluation result of the actual vehicle in the second bench test evaluation step. Note that based on the evaluation result of the second bench test evaluation step, feedback may be provided by, for example, changing the vehicle model in the virtual evaluation step.

[0059] Furthermore, a third comparison step can be performed to compare the evaluation result of the actual vehicle in the road test evaluation step with the evaluation result of the actual vehicle in the second bench test evaluation step. Then, a third feedback step can be performed to provide feedback to the second bench test evaluation step so that the evaluation result of the actual vehicle in the second bench test evaluation step matches the evaluation result of the actual vehicle in the road test evaluation step. Note that based on the evaluation result of the second bench test evaluation step, feedback may be provided by, for example, changing the vehicle model in the virtual evaluation step or the first bench test evaluation step.

[0060] <Effects of the Present Embodiment> According to the on-road driving test evaluation method of this embodiment, since at least three steps including a virtual evaluation step, a first bench test evaluation step, and an on-road driving test evaluation step are performed, the validity of the driving environment model, driving mode model, and vehicle model used in the virtual evaluation step can be verified using the evaluation results of the first bench test evaluation step. Regardless of the experience and skills of the model creator, a model compliant with the on-road driving test can be created. Also, by performing the virtual evaluation step and the first bench test evaluation step, the evaluation of the on-road driving test compliant with regulations such as RDE can be front-loaded. As a result, the efficiency of automobile development compliant with the on-road driving test can be improved. Further, by performing the on-road driving test evaluation step in addition to the virtual evaluation step and the first bench test evaluation step, the validity of the virtual evaluation step and the first bench test evaluation step can also be verified.

[0061] <Other modified embodiments> Note that the present invention is not limited to the above-described embodiment.

[0062] For example, the on-road driving test evaluation method of the above-described embodiment had a second bench test evaluation step, but it may also be a method without a second bench test evaluation step.

[0063] Also, in the on-road driving test evaluation method of the above-described embodiment, it may be a method having either the first bench test evaluation step or the second bench test evaluation step between the virtual evaluation step and the on-road driving test evaluation step.

[0064] When measuring the solid particle number (PN) in the above-described embodiment, both the stationary exhaust gas analyzer and the in-vehicle exhaust gas analyzer will have a solid particle number measurement unit. Here, the PN counting efficiency may be different between the stationary exhaust gas analyzer and the in-vehicle exhaust gas analyzer. For example, the PN detection efficiency of the stationary solid particle number measurement unit may be set to be able to measure particles with a smaller particle size than the PN detection efficiency of the in-vehicle solid particle number measurement unit. Note that, for example, a laser scattering type condensation particle counter (CPC) is used for the solid particle number measurement unit. Generally, the PN detection efficiency is defined such that the number of particles with a predetermined particle size (e.g., set to 23 nm, 10 nm, etc.) can be measured with a detection efficiency of 50%.

[0065] In the first bench test evaluation step (first bench test apparatus 3) or the second bench test evaluation step (second bench test apparatus 4), it is desirable to use a stationary solid particle number measurement unit calibrated to have the same PN detection efficiency as the in-vehicle solid particle number measurement unit. In the example described above, an example of using a stationary exhaust gas analyzer in the first bench test evaluation step (first bench test apparatus 3) or the second bench test evaluation step (second bench test apparatus 4) was shown, but an in-vehicle exhaust gas analyzer may also be used.

[0066] Note that the stationary solid particle number measurement unit may be configured to be switchable between a PN detection efficiency set to be able to measure particles with a smaller particle size than the PN detection efficiency of the in-vehicle solid particle number measurement unit and a PN detection efficiency equivalent to that of the in-vehicle solid particle number measurement unit, and may be switchable between a test on a chassis dynamometer (e.g., WLTC) and a test simulating a road driving test.

[0067] In addition, the test specimen of the above embodiment may have an advanced driver assistance system (ADAS). In this case, as shown in FIG. 6, at least one of various sensor models obtained by digitizing various sensors (such as radar, lidar, or camera, etc.) required for the advanced driver assistance system (ADAS) or an ADAS model obtained by digitizing the ADAS system is stored in the relational data storage unit 21. Further, the driving environment model includes a model in which the presence or absence of other vehicles, the speed difference from the vehicle ahead, etc. are digitized. Then, based on the driving scenario based on the driving environment model, the driving mode model, the sensor model, and the ADAS model may be coordinated to perform the on-road driving test evaluation method of the above embodiment. With this configuration, the on-road driving test of the test specimen having ADAS can be evaluated. In particular, it is possible to evaluate the behavior of the vehicle when switching from the driver's driving to autonomous driving and the behavior of the vehicle when switching from autonomous driving to the driver's driving.

[0068] Furthermore, the test specimen of the above embodiment was an engine vehicle, but it may also be a hybrid vehicle in which the engine and the battery operate in cooperation. In this case, as shown in FIG. 7, the driving mode changes according to the state of charge (SOC) of the battery of the hybrid vehicle, and the emissions of exhaust gas also change. Therefore, a battery model obtained by digitizing various parameters of the battery of the hybrid vehicle is stored in the relational data storage unit 21, and in addition to the models of the above embodiment, the battery model may be used to perform the on-road driving test evaluation method of the above embodiment. Note that the present invention is not limited to engine vehicles or hybrid vehicles, and can also be applied to electric vehicles (EV) or fuel cell vehicles (FCV).

[0069] In addition, in the above embodiment, using only the simulation device 2 and the first bench test device 3 in FIG. 1, it is also possible to front-load the evaluation of the on-road driving test conforming to regulations such as the RDE test for the engine as the test specimen. Also, using only the simulation device 2 and the second bench test 4 in FIG. 1, it is also possible to front-load the evaluation of the on-road driving test conforming to regulations such as the RDE test for the vehicle drive system such as the powertrain as the test specimen.

[0070] The above-described sensor model, ADAS model, or battery model may be included in the vehicle model as part of the vehicle model.

[0071] In addition, in the bench evaluation test step, when testing by combining part or all of the actual vehicle and part or all of the vehicle model, part or all of the actual vehicle and part or all of the vehicle model may partially overlap, or part of the actual vehicle or part of the vehicle model may be omitted. Furthermore, in the bench evaluation test step, all or part of the driving environment model may be used, or all or part of the driving mode model may be used.

[0072] Moreover, in the simulation device 2, further simulation may be performed using an exhaust gas emission model.

[0073] In addition, in the on-road driving test evaluation method, fuel consumption may be added as an evaluation item.

[0074] The on-road driving test compliant with regulations is not limited to RDE, and may be various on-road driving tests defined by laws or regulations of each country.

[0075] In addition, various modifications and combinations of embodiments may be made as long as they do not contravene the spirit of the present invention.

Explanation of Reference Numerals

[0076] 100 ··· Vehicle test system 2 ··· Simulation device 3 ··· First bench test device 4 ··· Second bench test device

Claims

1. A road running test evaluation method for evaluating a road running test that complies with regulations by conducting a bench test on a test specimen that is an actual vehicle or a part thereof, comprising: a virtual evaluation step of simulating the road running test using a running environment model that models the running environment, a driving mode model that models the driving mode, and a vehicle model that models the actual vehicle; a bench test evaluation step of simulating the road running test by combining a part or all of the actual vehicle, a part or all of the vehicle model, a part or all of the running environment model, and a part or all of the driving mode model, and conducting a bench test on a part or all of the actual vehicle; a road running test evaluation step of conducting the road running test on the actual vehicle in an actual running environment; a feedback step of feeding back to the virtual evaluation step so that the evaluation result of the vehicle model in the virtual evaluation step matches the evaluation result of a part or all of the actual vehicle in the bench test evaluation step, or feeding back to the bench test evaluation step so that the evaluation result of a part or all of the actual vehicle in the bench test evaluation step matches the evaluation result of the actual vehicle in the road running test evaluation step.

2. The bench test evaluation step includes a first bench test evaluation step of simulating the road running test by combining a part including the engine of the actual vehicle, a part or all of the vehicle model, a part or all of the running environment model, and a part or all of the driving mode model, and conducting a bench test on a part including the engine of the actual vehicle. The road running test evaluation method according to claim 1.

3. The bench test evaluation step further includes a second bench test evaluation step of simulating the road running test by combining the actual vehicle, a part or all of the running environment model, and a part or all of the driving mode model, and conducting a bench test on the actual vehicle between the first bench test evaluation step and the road running test evaluation step. The road running test evaluation method according to claim 2.

4. A first comparison step of comparing the evaluation result of a part including the engine of the actual vehicle in the first bench test evaluation step with the evaluation result of the vehicle model in the virtual evaluation step; A second comparison step of comparing the evaluation result of the actual vehicle in the second bench test evaluation step with some of the evaluation results including the engine of the vehicle in the first bench test evaluation step; The road running test evaluation method according to claim 3, comprising at least one of a third comparison step of comparing the evaluation result of the actual vehicle in the road running test evaluation step with the evaluation result of the actual vehicle in the second bench test evaluation step.

5. The feedback step includes A first feedback step of feeding back to the virtual evaluation step so that the evaluation result of the vehicle model in the virtual evaluation step matches some of the evaluation results including the engine of the actual vehicle in the first bench test evaluation step; A second feedback step of feeding back to the first bench test evaluation step so that some of the evaluation results including the engine of the actual vehicle in the first bench test evaluation step match the evaluation result of the actual vehicle in the second bench test evaluation step; The road running test evaluation method according to claim 3 or 4, comprising at least one of a third feedback step of feeding back to the second bench test evaluation step so that the evaluation result of the actual vehicle in the second bench test evaluation step matches the evaluation result of the actual vehicle in the road running test evaluation step.

6. The road running test evaluation step is performed using an in-vehicle exhaust gas analyzer. The road running test evaluation method according to any one of claims 3 to 5, wherein the second bench test evaluation step is performed using a stationary or in-vehicle exhaust gas analyzer.

7. The second bench test evaluation step is performed using a stationary exhaust gas analyzer. The detection efficiency of the solid particle number measurement unit of the stationary exhaust gas analyzer is the same as that of the solid particle number measurement unit of the in-vehicle exhaust gas analyzer. The road running test evaluation method according to claim 6.

8. Compare the exhaust gas test results in at least any two of the first bench test evaluation step, the second bench test evaluation step, and the road running test evaluation step, and the measurement components used for the comparison of the exhaust gas test results are at least one of carbon dioxide (CO2), carbon monoxide (CO), particulate matter (PM), particulate matter number (PN), ammonia (NH3), nitrous oxide (N2O), nitrogen oxides (NOx), or total hydrocarbon (THC). The road running test evaluation method according to claim 6 or 7.

9. The bench test evaluation step is to operate a part or all of the actual vehicle based on the driving mode model used in the virtual evaluation step. The road running test evaluation method according to any one of claims 1 to 8.

10. Based on the driving mode reproduced in the first bench test evaluation step, reproduce the driving mode of the second bench test evaluation step. The second bench test evaluation step is to drive the actual vehicle by a driver or drive the actual vehicle by an autonomous driving robot based on the driving mode model used in the first bench test evaluation step. The road running test evaluation method according to claim 3 or any one of claims 4 to 9 citing claim 3.

11. The driving environment model of the first bench test evaluation step or the second bench test evaluation step is reproduced by connecting pipes to the intake side and the exhaust side of the engine and controlling the pressure through the pipes. The road running test evaluation method according to any one of claims 3 to 10.

12. In the virtual evaluation step, the combination of parameters constituting the driving mode model is associated with at least one of RPA (Relative Positive Acceleration) or vapos_[95] (Relative Positive Acceleration 95th percentile) so as to conform to a road running test compliant with regulations. The road running test evaluation method according to any one of claims 1 to 11.

13. The test specimen has an advanced driver assistance system (ADAS). The virtual evaluation step is the on-road driving test evaluation method according to any one of claims 1 to 12, which simulates the on-road driving test by using at least one of a sensor model obtained by modeling sensors required for ADAS or an ADAS model obtained by quantifying the ADAS, in addition to the driving environment model, the driving mode model, and the vehicle model.

14. The test specimen is one in which an engine and a battery operate in cooperation. The virtual evaluation step is the on-road driving test evaluation method according to any one of claims 1 to 13, which simulates the on-road driving test by using a battery model obtained by modeling the battery, in addition to the driving environment model, the driving mode model, and the vehicle model.

15. A vehicle test system for evaluating an on-road driving test that complies with regulations by conducting a bench test on a test specimen that is an actual vehicle or a part thereof, A simulation device that simulates the on-road driving test by using a driving environment model obtained by modeling a driving environment, a driving mode model obtained by modeling a driving mode, and a vehicle model obtained by modeling the actual vehicle, A bench test device that simulates the on-road driving test by combining a part of the actual vehicle with a part or all of the vehicle model, a part or all of the driving environment model, and a part or all of the driving mode model, and conducting a bench test on a part of the actual vehicle, or by combining the actual vehicle with a part or all of the driving environment model and a part or all of the driving mode model, and conducting a bench test on the actual vehicle, A vehicle test system including a host management device that feeds back to the simulation device such that an evaluation result of the vehicle model simulated in the simulation device matches an evaluation result of a part or all of the actual vehicle including the engine in the bench test device.

16. An on-road driving test evaluation program for evaluating an on-road driving test that complies with regulations by conducting a bench test on a test specimen that is an actual vehicle or a part thereof, Causing a computer to simulate the on-road driving test by using a driving environment model obtained by modeling a driving environment, a driving mode model obtained by modeling a driving mode, and a vehicle model obtained by modeling the actual vehicle. By combining part or all of the actual vehicle, part or all of the vehicle model, part or all of the driving environment model, and part or all of the driving pattern model, and subjecting part or all of the actual vehicle to a bench test using a bench test device, the road running test is simulated. A road running test evaluation program that feeds back so that the evaluation result of the vehicle model simulated in the computer matches the evaluation result of part or all of the actual vehicle including the engine in the bench test device. **Claim 17**: A road running test evaluation method for evaluating a road running test conforming to regulations by subjecting a test specimen, which is an actual vehicle or a part thereof, to a bench test, A virtual evaluation step of simulating the road running test using a driving environment model that models the driving environment, a driving pattern model that models the driving pattern, and a vehicle model that models the actual vehicle, A bench test evaluation step of simulating the road running test by combining part or all of the actual vehicle, part or all of the vehicle model, part or all of the driving environment model, and part or all of the driving pattern model, and subjecting part or all of the actual vehicle to a bench test, A road running test evaluation step of performing the road running test on the actual vehicle in an actual driving environment, and The bench test evaluation step includes: A first bench test evaluation step of simulating the road running test by combining part of the actual vehicle including the engine, part or all of the vehicle model, part or all of the driving environment model, and part or all of the driving pattern model, and subjecting part of the actual vehicle including the engine to a bench test, A second bench test evaluation step of simulating the road running test by combining the actual vehicle, part or all of the driving environment model, and part or all of the driving pattern model, and subjecting the actual vehicle to a bench test between the first bench test evaluation step and the road running test evaluation step, A first feedback step of feeding back to the virtual evaluation step so that the evaluation result of the vehicle model in the virtual evaluation step matches the evaluation result of part of the actual vehicle including the engine in the first bench test evaluation step. A second feedback step of feeding back to the first bench test evaluation step so that some evaluation results including the engine of the actual vehicle in the first bench test evaluation step match the evaluation results of the actual vehicle in the second bench test evaluation step, A road running test evaluation method comprising at least one of the following steps: a third feedback step of feeding back to the second bench test evaluation step so that the evaluation results of the actual vehicle in the second bench test evaluation step match the evaluation results of the actual vehicle in the road running test evaluation step.

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