Test specimen testing system and test specimen testing method

Abstract

The present invention provides a test specimen testing system 100 for testing a test specimen while reproducing splashing generated from a vehicle traveling at the periphery thereof, the test specimen testing system being used to test a test specimen W, which is a vehicle or part thereof, and comprising: a testing device 2 having the test specimen W installed therein or connected thereto; and a splash simulating device 3 for simulating splashing from another vehicle.

Description

Specimen testing system and specimen testing method

[0001] The present invention relates to a test specimen testing system and a test specimen testing method for testing a vehicle or a part thereof.

[0002] Conventionally, as disclosed in Patent Document 1, a vehicle driving test device has been considered that includes a real vehicle running bench device on which a test vehicle is mounted and an environmental reproduction mechanism that reproduces the environment around the test vehicle. The environmental reproduction mechanism includes a rainfall facility, a fog-generating facility, etc. This vehicle driving test device allows testing under rainy conditions by replicating rain conditions with the rainfall facility while the test vehicle is running on the real vehicle running bench.

[0003] However, the vehicle driving test device described above does not reproduce the splash caused by tire rotation when surrounding vehicles are traveling in the rain. Therefore, the test of the test vehicle in the rain differs from the real environment. In particular, when evaluating the sensor installed in the test vehicle, it is important to reproduce the sensor's recognition environment. However, since the vehicle driving test device described above cannot reproduce the splash, it is not possible to perform an evaluation that takes the splash into consideration.

[0004] Japanese Patent Application Publication No. 57-184943

[0005] Therefore, the present invention has been made in consideration of the above-mentioned problems, and its main objective is to test a test specimen while reproducing splashes generated from other vehicles traveling in the vicinity, such as in front, to the side, or behind.

[0006] In other words, the specimen testing system of the present invention is a specimen testing system for testing a specimen that is a vehicle or a part thereof, and is characterized by comprising a test device to which the specimen is installed or connected, and a splash simulation device for simulating splashes from other vehicles traveling around the specimen.

[0007] With this configuration, the test specimen is provided with a splash simulation device that simulates splashes from other vehicles traveling around the test specimen, such as in front, to the side, or behind, so that the test specimen can be tested while reproducing splashes generated from other vehicles traveling around the test specimen, such as in front, to the side, or behind.

[0008] In a specific embodiment of the splash simulator, the splash simulator preferably includes a simulated rotating body that simulates the wheels of the other vehicle, and a water supply unit that supplies water to the simulated rotating body to generate splashes from the simulated rotating body. With this configuration, water is supplied to the simulated rotating body that simulates the wheels of the other vehicle, and splashes are generated from the simulated rotating body, so that a test specimen can be tested while more realistically reproducing splashes generated from other vehicles traveling in the vicinity, such as in front, to the side, or behind.

[0009] In order to reproduce splashes that occur in a real environment, it is desirable to have a contact surface that comes into contact with the simulated rotating body and simulates the contact of the wheels with the ground.

[0010] As a specific embodiment of the contact surface, it is desirable that the contact surface is formed by a roller, a belt or a panel.

[0011] In order to reproduce splashes that occur in a real environment, it is desirable that the contact surface have irregularities that simulate the actual road.

[0012] The test specimen suitable for use with the test system of the present invention is preferably an autonomous vehicle or a vehicle or part thereof having an advanced driver assistance system, and is preferably equipped with a sensor for acquiring information about the surroundings.

[0013] A specific embodiment of the test device may be one that performs a simulated run of the test subject, or activates the test subject's automated driving system or advanced driver assistance system.

[0014] A specific example of a test device for simulating a run of the test specimen is one that has a rotating body on which the wheels of the test specimen are mounted, or a rotating body to which the axle, wheel, or wheel of the test specimen is connected.

[0015] The test specimen is an autonomous vehicle or a vehicle equipped with an advanced driver assistance system, or a part thereof, and has a sensor for acquiring information about the surroundings, and the splash simulator further includes a rotation control unit for controlling the rotation of the simulated rotating body, and the rotation control unit preferably controls the rotation of the simulated rotating body in conjunction with the vehicle speed of the test specimen simulated by the test device or a vehicle speed signal input to the autonomous driving system or advanced driver assistance system of the test specimen. With this configuration, splashes from a vehicle ahead, a vehicle to the side, or a vehicle behind the test specimen traveling at a similar speed can be reproduced.

[0016] In addition, some vehicles are equipped with splash guards, and in order to take this into consideration and reproduce the splash that occurs in a real environment, it is desirable to provide a splash guard on the test specimen side relative to the simulated rotating body.

[0017] In order to be able to change the distance between the vehicle in front, the vehicle to the side, or the vehicle behind the test specimen and thereby reproduce various situations, it is desirable to further provide a position change mechanism that changes the position of the simulated rotating body relative to the test specimen.

[0018] In order to reproduce splashes that occur in a real environment, it is desirable that the test system of the present invention further include a blower that blows air onto the simulated rotating body.

[0019] The specimen testing system of the present invention preferably further comprises a simulated structure disposed around the simulated rotating body and simulating the body of another vehicle traveling around the specimen. Even with this configuration, splashes occurring in a real environment can be reproduced.

[0020] In addition, as a specific embodiment of the splash simulator, the splash simulator may have a plurality of nozzles with different spray characteristics. Here, different spray characteristics include different spray direction, spray amount, spray distance, spray spread angle, and / or spray droplet size. In such a configuration, some of the plurality of nozzles may be used to simulate splashes kicked up from the wheels, and other nozzles may be used to simulate splashes caused by airflow behind other vehicles.

[0021] Furthermore, the specimen testing method according to the present invention is a testing method for testing a specimen that is a vehicle or a part thereof, characterized in that water is supplied to a simulated rotating body that simulates the wheels of another vehicle traveling around the specimen, and the specimen is tested using a testing device while splashing from the simulated rotating body.

[0022] Furthermore, the specimen testing system according to the present invention is a specimen testing system for testing a specimen that is a vehicle or a part thereof, and is characterized by comprising a test device on which the specimen is installed or connected, a simulated rotating body that simulates the wheels of another vehicle traveling around the specimen, and a water supply unit that supplies water to the simulated rotating body to generate splashes from the simulated rotating body.

[0023] Furthermore, a specimen testing system according to the present invention is a specimen testing system for testing a specimen that is a vehicle or a part thereof, and is characterized by comprising a testing device on which the specimen is installed or connected, and a water supply unit that supplies water to a wheel of the specimen or to a simulated rotating body that is arranged around the wheel and simulates the wheel, thereby generating splashes from the wheel or the simulated rotating body. With this system, it is possible to test the specimen while reproducing splashes generated from the wheels of the vehicle.

[0024] According to the present invention as described above, it is possible to test a test specimen while reproducing splashes generated from other vehicles traveling in front, to the side, or behind.

[0025] FIG. 1 is a schematic diagram showing a scenario of a specimen testing method using a specimen testing system according to one embodiment of the present invention. FIG. 2 is an example of an overall schematic diagram of a specimen testing system according to the same embodiment. FIG. 3 is another example of an overall schematic diagram of a specimen testing system according to the same embodiment. FIG. 4 is a side view schematically showing the configuration of a splash simulator according to the same embodiment. FIG. 5 is a schematic diagram showing the unevenness of a contact surface according to the same embodiment. FIG. 6 is a schematic diagram showing an example configuration of a contact surface according to the same embodiment. FIG. 7 is a schematic diagram showing an example using a structure and a blower according to the same embodiment. FIG. 8 is a schematic diagram showing an example configuration of controlling the rotation of a simulated rotor according to the traveling speed of a specimen according to the same embodiment. FIG. 9 is a schematic diagram showing an example using a position changing mechanism according to the same embodiment. FIG. 10 is an example of an overall schematic diagram of a specimen testing system according to a modified embodiment. FIG. 11 is an example of an overall schematic diagram of a specimen testing system according to the modified embodiment.

[0026] An embodiment of a specimen testing system according to the present invention will be described below with reference to the drawings. Note that, for ease of understanding, all of the drawings shown below are drawn in a schematic manner, with appropriate omissions or exaggerations. Identical components are designated by the same reference numerals, and their descriptions will be omitted where appropriate.

[0027] The specimen testing system 100 of this embodiment is used to test, for example, a vehicle equipped with an advanced driver assistance system (ADAS) (hereinafter referred to as an ADAS vehicle), an autonomously driving vehicle (hereinafter referred to as an AD vehicle), or a part of either of them, a specimen W. In this embodiment, a completed ADAS vehicle or AD vehicle is used as the specimen W, but the specimen W may also be an incomplete vehicle (part of an ADAS vehicle or AD vehicle) that is not a completed vehicle as long as it is in a drivable state, or may be a single sensor (for example, a camera, millimeter-wave radar, infrared sensor, or LiDAR).

[0028] 1 and 2 show an example of a scenario of a specimen testing method using the specimen testing system 100 of this embodiment. Here, a method is considered in which, while the specimen W is running on the specimen testing system 100, the surrounding environment in front of, behind, or to the sides of the specimen W is changed, or a pseudo signal is input to a sensor of the specimen W, to evaluate the behavior of the specimen W (for example, lane keeping, overtaking, lane changing, emergency avoidance steering, etc.). The sensor of the specimen W acquires information about the surroundings, and examples thereof include a camera, millimeter-wave radar, an infrared sensor, and a lidar (LiDAR).

[0029] Specifically, the specimen testing system 100 of this embodiment includes a test device 2 on which the specimen W is installed or connected, and a splash simulation device 3 that simulates splashes from other vehicles traveling around (in front, to the side, or behind) the specimen W, as shown in Figures 2 and 3.

[0030] The test apparatus 2 has a rotating body (see FIG. 2) to which the axle, wheel, or axle of the test specimen is connected, or a rotating body 2R (see FIG. 3) on which the wheel of the test specimen W is installed. The rotating body on which the wheel of the test specimen W is installed may be, for example, a roller of a chassis dynamometer, or a free roller that rotates freely. Furthermore, the rotating body to which the wheel, wheel, or axle of the test specimen W is connected may be, for example, a dynamometer, a motor, or a rotating shaft. Furthermore, these may be connected to the wheel, wheel, or axle via a universal joint or the like.

[0031] The test apparatus 2 shown in FIG. 2 is configured such that a front-wheel motor M1 is connected to the wheels WH or axles of the left and right front wheels W1 via a rotating shaft 21 (front rotating shaft), and a rear-wheel motor M2 is connected to the wheels WH or axles of the left and right rear wheels W2 via a rotating shaft 22 (rear rotating shaft). The rotating shaft 21 connected to the wheels WH or axles of the left and right front wheels W1 can have an extension and contraction structure such as a spline function with a joint having a floating function, such as a constant velocity joint or a universal joint. The rotating shaft 22 connected to the wheels WH or axles of the left and right rear wheels W2 can also have an extension and contraction structure such as a spline structure. The test specimen W may be placed on a support stand via a freewheel hub, or may be fixed in a state where it is suspended above the road surface using a fixing mechanism such as a jack.

[0032] As shown in Figures 2 to 4, the splash simulation device 3 includes a simulated rotating body 31 that simulates the wheels of other vehicles traveling around the test piece W, and a water supply unit 32 that supplies water to the simulated rotating body 31 to generate splashes from the simulated rotating body 31.

[0033] The simulated rotating body 31 is disposed, for example, in front of the test specimen W, and simulates the wheels of another vehicle traveling around the test specimen W. The simulated rotating body 31 may be, for example, constituted by a wheel, may be a simulated wheel, or may be an actual vehicle. In the case of a simulated wheel, it is desirable that the simulated wheel has a tread pattern of a wheel.

[0034] The simulated rotating bodies 31 are configured to be rotatable by a motor 311. In this embodiment, there are two simulated rotating bodies 31 to simulate a pair of left and right wheels, and these two simulated rotating bodies 31 are connected by a drive shaft 312, to which a motor 311 is connected. When the drive shaft 312 is rotated by the motor 311, the two simulated rotating bodies 31 rotate in synchronization. The motor 311 is controlled by a rotation control unit 3c, and is controlled so that the simulated rotating bodies 31 rotate at a desired rotation speed.

[0035] Here, the splash simulator 3 has a contact surface 33 that comes into contact with the simulated rotating body 31 to simulate the contact of the wheels with the ground. As shown in FIG. 5, this contact surface 33 has unevenness 33x that simulates an actual road. As shown in FIG. 6, the contact surface 33 is formed by a roller, a belt, or a panel. The roller and the belt rotate following the rotation of the simulated rotating body 31. The panel is fixed regardless of the rotation of the simulated rotating body 31 and has a low coefficient of friction so that the simulated rotating body 31 can slide. Alternatively, when a panel is used, it is possible to adjust the installation load of the simulated rotating body 31 relative to the panel rather than using a panel with a low coefficient of friction.

[0036] The water supply unit 32 supplies water from the front of the simulated rotor 31 (the side opposite to the specimen W). The water supply unit 32 has a nozzle 321 provided in front of the simulated rotor 31 and a water supply source 322 that supplies water to the nozzle 321. One or more nozzles 321 can be provided for one simulated rotor 31.

[0037] The water supply unit 32 may be configured to adjust the amount of water supplied to the dummy rotor 31 in order to adjust the amount of splash. The water supply source 322 may have a water volume adjustment mechanism (not shown), or a water volume adjustment mechanism (not shown), such as a valve, may be provided between the water supply source 322 and the nozzle 321. The water volume adjustment mechanism is controlled by the water volume control unit 3a (see FIGS. 2 to 4). For example, it may be possible to increase the amount of water supplied to the dummy rotor 31 as the traveling speed increases. It may also be possible to increase the amount of water supplied to the dummy rotor 31 as the expected amount of precipitation increases.

[0038] The splash simulator 3 of this embodiment may be provided with a splash guard 34 on the side of the simulated rotor 31 facing the specimen W. The splash guard 34 simulates a splash guard provided on a vehicle.

[0039] 7, the splash simulator 3 may further include a simulated structure 36 that is provided around the simulated rotor 31 and simulates the body of a vehicle traveling around the specimen W. This simulated structure 36 may be the body of an actual vehicle, a dummy vehicle that simulates the body of a vehicle, or an equivalent aerodynamic dummy whose aerodynamic characteristics are equivalent to those of the body of an actual vehicle. The simulated structure 36 may also be configured to include a splash guard 34. Furthermore, the simulated structure 36 also serves as a target for the sensors of the specimen W.

[0040] Furthermore, in order to simulate actual running, the splash simulator 3 may further include a blower 35 that blows air onto the simulated rotating body 31. This blower 35 may be provided in front of the simulated rotating body 31 (on the opposite side from the specimen W). The blower 35 may also be configured to be movable relative to the simulated rotating body 31 so that the direction of air blowing relative to the simulated rotating body 31 can be changed. Furthermore, the amount of air blown by the blower 35 may be changed by the air amount control unit 3b according to the running speed of the specimen W.

[0041] Furthermore, as shown in FIG. 8 , the rotation control unit 3c of the splash simulator 3 may control the rotation of the simulated rotor 31 in conjunction with the vehicle speed of the specimen W. Specifically, the rotation control unit 3c controls the rotation speed of the simulated rotor 31 to simulate a vehicle traveling within a predetermined range of relative speed difference with respect to the traveling speed of the specimen W. Alternatively, the rotation control unit 3c may control the rotation speed of the simulated rotor 31 to simulate another vehicle traveling at a predetermined relative speed difference or more, assuming that the other vehicle is overtaking or being overtaken by the specimen W. Here, the rotation control unit 3c may acquire speed information from the specimen W, or may acquire speed information of the specimen W from the control device CLT of the testing device 2.

[0042] In addition, as shown in FIG. 9 , the specimen testing system 100 of this embodiment may further include a position change mechanism 4 that changes the position of the splash simulator 3 relative to the specimen W. The position change mechanism 4 changes the position of the simulated rotor 31 relative to the specimen W, for example, by changing the position of the splash simulator 3. The position change mechanism 4 includes, for example, a base 41 on which the splash simulator 3 is installed and a movement mechanism 42 that moves the base 41 forward and backward, left and right, or diagonally. The movement mechanism 42 may be configured using wheels. The position change mechanism 4 may be configured to move the simulated rotor 31 forward and backward relative to the specimen W, or may be configured to move the simulated rotor 31 left and right relative to the specimen W, or may be configured to do both. The position change mechanism 4 changes the position of the water supply unit 32 as well as the simulated rotor 31.

[0043] <Effects of this embodiment> According to the specimen testing system 100 of this embodiment configured as described above, water is supplied to the simulated rotating body 31 that simulates the wheels of other vehicles traveling around the front, side, rear, etc. of the specimen W, and splashes are generated from the simulated rotating body 31, so that the specimen W can be tested while reproducing splashes generated from other vehicles traveling around the front, side, rear, etc.

[0044] <Other Embodiments> For example, although the simulated rotating bodies 31 in the above embodiment are a pair of left and right simulated rotating bodies 31, there may be a single simulated rotating body 31 to simulate, for example, a motorcycle traveling in the vicinity.

[0045] The inclination angle of the contact surface 33 of the dummy rotating body 31 may be made changeable. With this configuration, splashing can be reproduced according to the gradient of the road surface.

[0046] Furthermore, the specimen testing system 100 of the embodiment may be combined with a rainfall device in addition to the splash simulator 3 .

[0047] The water supply unit 32 in the above embodiment supplies liquid water, but it may also supply frozen water (snow), or a mixture (sleet) of liquid water and frozen water (snow).

[0048] Furthermore, the water supply unit 32 may supply water from below the simulated rotor 31. In this case, the water supply unit 32 may be configured to form a recess in the contact surface 33 that can store water, and supply water to the simulated rotor 31 by storing water in the recess. With this configuration, it is possible to reproduce the splashing that occurs when running on a wet road surface or a puddle on the road surface.

[0049] The test device in the above embodiment physically simulates the running of the test specimen W, but may be a computer such as a simulator that activates the automated driving system or advanced driver assistance system of the test specimen W by inputting a simulated signal to the test specimen W. In this case, the rotation control unit 3c may control the rotation of the simulated rotor in conjunction with a vehicle speed signal input to the automated driving system or advanced driver assistance system of the test specimen W.

[0050] In addition to the configuration of the above embodiment, the splash simulator 3 may be configured using multiple nozzles that generate splashes, as shown in Fig. 10. It may also be configured using multiple nozzles with different ejection characteristics. This makes it possible to generate splashes with different characteristics. While Fig. 10 illustrates the splash simulator 3 using two nozzles 301a and 301b, the number of nozzles is not limited to this.

[0051] The splash simulator 3 includes a plurality of nozzles 301a, 301b and water supply channels 302a, 302b that supply water to the nozzles 301a, 301b. The water supply channels 302a, 302b are connected to a water supply source 303. The water supply source 303 is composed of, for example, a water storage tank 303a and a water compressor 303b. Each water supply channel 302a, 302b is provided with an adjustment valve 304a, 304b for adjusting the supply flow rate or supply pressure of water supplied to the nozzles 301a, 301b. The valve openings of the adjustment valves 304a, 304b are independently adjusted by a valve control unit 305.

[0052] The nozzles 301a, 301b are configured to have different spray characteristics. For example, the spray directions can be configured to be different by adjusting the installation angles of the nozzles 301a, 301b. The spray spread angles can be configured to be different by selecting the specifications of the nozzles 301a, 301b. The spray amounts can be configured to be different by adjusting the valve openings of the adjustment valves 304a, 304b. The sizes of the sprayed splash droplets can be configured to be different by selecting the specifications of the nozzles 301a, 301b. The spray pressures can be configured to be different by adjusting the valve openings of the adjustment valves 304a, 304b.

[0053] By making the injection characteristics different from each other as described above, one of the multiple nozzles 301a, 301b can be used as a nozzle for simulating splashes kicked up from the wheels of other vehicles, and the other of the multiple nozzles 301a, 301b can be used as a nozzle for simulating splashes caused by being kicked up by the rear airflow due to the shape of the other vehicle.

[0054] The nozzle for simulating splashes kicked up from the wheels can simulate splashes caused by the tire shape, tire size, and tire rotation speed, while the nozzle for simulating splashes caused by airflow from the vehicle can simulate splashes caused by the body shape of other vehicles.

[0055] Furthermore, as shown in FIG. 11 , the specimen testing system 100 may include a splash simulator 3 that generates splash from the wheels of the vehicle. That is, the specimen testing system 100 includes a test apparatus 2 on which a specimen W is installed or connected, and a second splash simulator that simulates splash from the wheels of the specimen W. The second splash simulator includes a water supply unit 6 that supplies water to the wheels of the specimen W or to a simulated rotating body 5 arranged around the wheels and simulating the wheels, thereby generating splash from the wheels or the simulated rotating body. Here, the test apparatus 2 is the same as in the above embodiment. The water supply unit 6 has a configuration similar to the water supply unit 32 in the above embodiment, and includes a nozzle 61 and a water supply source 62 that supplies water to the nozzle 61. When supplying water to the wheels, water may be supplied to the left and right rear wheels, or to the left and right front wheels. Furthermore, the simulated rotating bodies 5 may be provided around each of the left and right rear wheels, or around each of the left and right front wheels. The figure shows an example in which the simulated rotating bodies 5 are provided around each of the left and right rear wheels, and the water supply unit 6 supplies water to the simulated rotating bodies 5. These configurations may or may not be combined with the above-described embodiment. The second splash simulator may use a plurality of nozzles with different spray characteristics, as in the configuration shown in FIG. 10 .

[0056] In addition, various modifications and combinations of the embodiments may be made as long as they do not go against the spirit of the present invention.

[0057] According to the present invention, it is possible to test a specimen while reproducing splashes generated from vehicles traveling nearby.

[0058] REFERENCE SIGNS LIST 100... Specimen testing system W... Specimen 2... Testing device 3... Splash simulation device 31... Simulated rotating body 3c... Rotation control unit 32... Water supply unit 33... Contact surface 34... Splash guard 35... Blower 36... Simulated structure 4... Position changing mechanism

Claims

1. A test piece testing system for testing a test piece that is a vehicle or a part thereof, a test device to which the test specimen is installed or connected; a splash simulator that simulates splashes from other vehicles traveling around the specimen.

2. The splash simulator is a simulated rotating body that simulates the wheel of the other vehicle; 2. The specimen testing system according to claim 1, further comprising a water supply unit that supplies water to the simulated rotating body to generate splashes from the simulated rotating body.

3. 3. The specimen testing system according to claim 2, further comprising a contact surface that contacts the simulated rotating body to simulate the ground contact of the wheels of the other vehicle.

4. 4. The specimen testing system according to claim 3, wherein the contact surface is formed by a roller, a belt, or a panel, and has projections and depressions that simulate an actual road.

5. 5. The specimen testing system according to claim 2, further comprising a splash guard provided on the specimen side with respect to the simulated rotating body.

6. 5. The test specimen testing system according to claim 1, wherein the test specimen is an autonomous vehicle or a vehicle having an advanced driver assistance system, or a part thereof, and has a sensor for acquiring information about the surroundings.

7. 7. The test specimen testing system according to claim 6, wherein the test device causes the specimen to undergo a simulated run or activates an automated driving system or an advanced driver assistance system of the specimen.

8. 5. The specimen testing system according to claim 1, wherein the test device has a rotating body on which the wheels of the specimen are mounted, or a rotating body to which the axle, wheel or wheel of the specimen is connected.

9. The test specimen is an autonomous vehicle or a vehicle having an advanced driver assistance system, or a part thereof, and has a sensor that acquires information about the surrounding area, The splash simulator further includes a rotation control unit that controls the rotation of the simulation rotor, 5. A specimen testing system as described in any one of claims 2 to 4, wherein the rotation control unit controls the rotation of the simulated rotating body in conjunction with the vehicle speed of the specimen being simulated by the test device or a vehicle speed signal input to the specimen's autonomous driving system or advanced driver assistance system.

10. 5. The system for testing a specimen according to claim 2, further comprising a position changing mechanism for changing the position of the dummy rotating body relative to the specimen.

11. 5. The specimen testing system according to claim 2, further comprising a blower that blows air onto the simulated rotating body.

12. 5. The specimen testing system according to claim 2, further comprising a simulated structure provided around the simulated rotating body, which simulates the body of another vehicle traveling around the specimen.

13. 2. The specimen testing system according to claim 1, wherein the splash simulator has a plurality of nozzles with different jetting characteristics.

14. A specimen testing method for testing a specimen that is a vehicle or a part thereof, A specimen testing method in which the specimen is tested by a test device while splashes are generated by a splash simulator that simulates splashes from other vehicles traveling around the specimen.

15. A test piece testing system for testing a test piece that is a vehicle or a part thereof, a test device to which the test specimen is installed or connected; A simulated rotating body that simulates the wheels of another vehicle traveling around the test specimen; a water supply unit that supplies water to the simulated rotating body to generate splashes from the simulated rotating body.

16. A test piece testing system for testing a test piece that is a vehicle or a part thereof, a test device to which the test specimen is installed or connected; a splash simulation device that simulates splash from the wheels of the specimen.