JP7496762B2 - Test device and method for testing a test object with rotating wheels - Google Patents

Description

The present invention relates to a test device, and more particularly to a test device and a test method for testing a test object having a rotating wheel.

Testing devices for testing structures with rotating wheels are known. Examples of such testing devices are described in Patent Documents 1, 2, and 3. In the techniques of Patent Documents 1 and 2, the state of the test object is determined by detecting the vibration of the test object. As a result of the test, it can be determined, for example, whether the maintenance of the test object has been performed correctly. In addition, the technique of Patent Document 3 realizes a simple and stable fixing device for the test object by measuring the load on the fixing device for the test object.

Although not a test device, a configuration for detecting vibrations in a structure that similarly includes wheels is described in Patent Documents 4 and 5.

In testing, it is important to properly connect the test object and the test equipment. For example, with one test device, an abnormality occurs during testing about once a month. In this case, the cause of the abnormality may be a malfunction of the test object or the test device, or an abnormality may develop due to self-excited vibration caused by an abnormal connection between the test object and the test device. For this reason, it is necessary to determine whether the connection between the test object and the test device is normal.

JP 2010-60529 A JP 2009-186363 A JP 2007-212148 A JP 2007-218791 A JP 2019-174180 A

However, with conventional technology, it was difficult to determine whether the connection between the test object and the test device was normal.

The judgment can be done manually, but doing so requires that the worker be familiar with the structure and behavior of the test equipment, and it is difficult to make an appropriate judgment for every test.

In Patent Documents 1 and 2, the vibration of the test object is detected, but it is difficult to accurately determine the connection between the test object and the test device based on the vibration of the test object alone.

In some cases, the judgment is made automatically using cameras, distance measuring sensors, vibration sensors, hydraulic sensors, temperature sensors, etc., but the judgment accuracy is low and, for example, it is not possible to appropriately change the judgment criteria depending on the type of test object.

Even when machine learning is used, it is difficult to apply a single trained model to multiple types of test objects, since the wheel diameter, etc., varies depending on the type of test object.

The present invention was made to solve these problems, and aims to provide a test device and test method for testing a test object having a rotating wheel that can properly determine whether the connection between the test object and the test device is normal.

An example of a test device according to the present invention is
1. A test device for testing a test object comprising a rotating wheel, the device comprising:
a first vibration sensor for detecting vibrations of the test object;
a second vibration sensor for detecting vibration of the testing apparatus;
A determination unit;
Equipped with
The determination unit estimates a state of the test object based on an output of the first vibration sensor,
The determination unit determines whether or not the connection between the test object and the testing device is normal based on a state of the test object and an output of the second vibration sensor.

An example of a test method according to the present invention is
A test method for testing a test object having a rotating wheel by a test device having a judgment unit, comprising:
The determination unit estimates a state of the test object based on an output of a first vibration sensor for detecting vibration of the test object;
determining whether or not a connection between the test object and the test device is normal based on the state of the test object estimated by the determination unit and an output of a second vibration sensor for detecting vibration of the test device;
Equipped with.
In this specification, the term "condition of the test object" refers to the maintenance state of the test object taking into account the type of test object.

The test device and test method of the present invention can properly determine whether the connection between the test object and the test device is normal.

1 is a schematic block diagram including a test device according to a first embodiment of the present invention. FIG. 2 is a diagram showing a more specific example of the configuration of the test device in FIG. 1 . 4 is a flowchart showing an example of a process executed by a determination unit in FIG. 1 . 2 is a diagram showing an example of the flow of information handled by a determination unit in FIG. 1 .

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
Embodiment 1.
1 is a schematic block diagram including a test apparatus 20 according to a first embodiment of the present invention. The test apparatus 20 is an apparatus for testing a test object 10 by carrying out a test method described in this specification. The test object 10 includes a rotating wheel 12 and a frame 11 for rotatably supporting the wheel 12. The test object 10 is, for example, a structure including a wheel (tire) of an automobile, but is not limited to this as long as it includes the wheel 12.

The test device 20 is connected to the test object 10 and tests the test object 10. The purpose of the test is to determine whether the maintenance state of the test object 10 after maintenance work, for example, is appropriate. The test device 20 also determines whether the connection between the test object 10 and the test device 20 is normal. This makes it possible to determine whether the test is in a state in which it can be performed normally (or whether the test has been performed normally).

The test device 20 comprises a device main body 30 and a judgment unit 40. The device main body 30 is connected to the test object 10. This connection is a physical connection and can transmit physical vibrations.

The device body 30 includes a fixture 31 and a roller 32. The roller 32 is an example of a rotating structure that rotates in association with the rotation of the wheel 12. The roller 32 passively rotates in response to the rotation of the wheel 12, for example, but may also be configured so that the roller 32 actively rotates to rotate the wheel 12.

In this embodiment, part of the connection between the device body 30 and the test object 10 is realized as a connection between the rollers 32 and the wheels 12. The connection between the rollers 32 and the wheels 12 means that they are in proper contact so that rotational motion can be properly transmitted, for example, via friction. As a specific example, when the rollers 32 and the wheels 12 rotate without substantial slippage, the contact can be said to be normal, and when slippage occurs between the rollers 32 and the wheels 12, the contact can be said to be abnormal. When the contact is normal and an unintended phenomenon occurs between the rollers 32 and the wheels 12 in the operation of the device, such as self-excited vibration, the connection can be said to be abnormal.

In addition, in this embodiment, another part of the connection between the device body 30 and the test object 10 is realized without passing through the rollers 32 and wheels 12. For example, part of the connection can be realized as a connection between the fixture 31 and the frame 11. The fixture 31 fixedly supports a part of the test object 10 (the frame 11 in this example) and applies an appropriate force to press the wheel 12 against the roller 32, thereby maintaining friction between the wheel 12 and the roller 32.

In this embodiment, the connection between the fixing device 31 and the frame 11 is realized through direct contact, but this may be a more indirect connection. For example, another connecting member may be interposed between the fixing device 31 and the frame 11.

The test device 20 is equipped with a first vibration sensor 33 and a second vibration sensor 34. These are attached to the device body 30.

The first vibration sensor 33 is a sensor for detecting vibrations of the test object 10, and is attached to the fixture 31, for example. Here, the direct object of vibration detection by the first vibration sensor 33 is the fixture 31, not the test object 10. However, as described above, the fixture 31 supports and fixes the test object 10, and the vibrations of the test object 10 are well transmitted to the fixture 31, so the first vibration sensor 33 can properly detect the vibrations of the test object 10.

The second vibration sensor 34 is a sensor for detecting vibrations of the test device 20 (in this example, vibrations of the device body 30), and is attached, for example, to the roller 32. In this example, the second vibration sensor 34 is attached directly to the roller 32, but it may also detect vibrations of the test device 20 indirectly via another member that supports and fixes the roller 32 (particularly its axle).

The connection between the device body 30 and the test object 10 may include a connection other than the two connection modes described above. The connection between the device body 30 and the test object 10 may be realized by only one of the two connection modes described above. Even with such a configuration, it is possible to distinguish and detect the vibration of the test object 10 and the vibration of the test device 20 by attaching the two types of vibration sensors to appropriate positions and/or by performing appropriate processing on the outputs of the two types of vibration sensors.

The judgment unit 40 judges whether the connection between the test object and the test device is normal or not. The judgment unit 40 has a configuration as, for example, a known computer, and includes, for example, a calculation means 41 and a storage means 42. The calculation means 41 includes, for example, a processor, and the storage means 42 includes, for example, a storage medium such as a semiconductor memory device and a magnetic disk device. Part or all of the storage medium may be a non-transient storage medium.

The determination unit 40 may also include input/output means. The input/output means may include, for example, input devices such as a keyboard and a mouse, and output devices such as a display and a printer.

The determination unit 40 may be realized, for example, by dedicated hardware, or may be realized by a combination of software and hardware. The determination unit 40 is not limited to being configured by a single computer, and may be realized by a computer system including multiple computers.

The determination unit 40 is communicatively connected to the device body 30. In particular, the determination unit 40 can receive the outputs of the first vibration sensor 33 and the second vibration sensor 34. For this purpose, the determination unit 40 may include a communication device such as a network interface.

The storage means 42 may store a program. The processor may execute this program, causing the judgment unit 40 to execute the method described in this specification. The storage means 42 may also store past test records, learning data used in machine learning, and machine learning results, and the judgment unit 40 may utilize the data stored in the storage means 42 for judgment.

Figure 2 shows a more specific example of the configuration of the test apparatus 20 in Figure 1. The test object 10 is placed between the fixture 31 and the roller 32. Although one test object 10 is shown in Figure 2, there may be two or more test objects 10. Also, in the example of Figure 2, one test object 10 has two wheels 12, but the number of wheels 12 is not limited to two.

One first vibration sensor 33 is attached to the fixture 31, but the number of first vibration sensors 33 may be two or more.

The test device 20 may include one or more test object holder load measurement sensors 35. In the example of FIG. 2, one test object holder load measurement sensor 35 is attached to the fixture 31. The test object holder load measurement sensor 35 detects the load of the damper in the test device 20. The type of sensor may be, for example, a pressure sensor, a camera, a laser displacement meter, or other sensor, but is not limited to these. For example, if the fixture 31 is hydraulic, the load on the test object holder appears in the hydraulic pressure, so a hydraulic sensor may be used. If the fixture 31 is a frame or belt type, the load on the test object holder appears in the form of strain or tension at the connection, so a strain sensor or tension sensor may be used.

The test device 20 may include one or more image capture devices 36. The image capture devices 36 include, for example, cameras having a known configuration, and capture images that include at least a portion of the test object 10.

In the example of FIG. 2, the roller 32 has two wheels. The device body 30 has a shaft 37, which rotatably supports the roller 32. The second vibration sensor 34 can be attached to the roller 32 or a gear box associated therewith. However, the attachment position of the second vibration sensor 34 is not limited thereto, and it may be attached to the roller 32, the shaft 37, or another part of the device body 30, for example. Note that, although one second vibration sensor 34 is attached in the example of FIG. 2, the number of second vibration sensors 34 may be two or more.

The operation of the test device 20 configured as above will be described below. In the test, the test device 20 first rotates the test object 10 (e.g., the wheel 12) and maintains the rotation speed at a predetermined value. In this state, the process shown in FIG. 3 is executed. Here, by maintaining the rotation speed at a predetermined value, it is possible to suppress variation between tests. Note that in this specification, when the term "rotation speed" is used, no particular distinction is made between the rotation distance (e.g., the distance traveled by the outer edge of the wheel) and the rotation angular velocity, but these can be converted into each other as appropriate.

Figure 3 is a flowchart showing an example of the process executed by the determination unit 40. This flowchart shows an example of a test method according to the present embodiment. The determination unit 40 executes the process of Figure 3 to determine whether or not the connection between the test object 10 and the test device 20 is normal. Also, Figure 4 is a diagram showing an example of the flow of information handled by the determination unit 40.

In the process of FIG. 3, the determination unit 40 first acquires the output of the first vibration sensor 33 (step S1). This output is a vibration signal that represents vibration. The vibration signal may be acquired via an amplifier or filter (not shown).

Next, the determination unit 40 estimates the state of the test object 10 based on the output of the first vibration sensor 33 (step S2). In this step S2, as shown in FIG. 4, the determination unit 40 first obtains the rotational frequency of the test object 10 based on the output (vibration signal) of the first vibration sensor 33. The rotational frequency of the test object 10 is, for example, the rotational frequency of the wheel 12, and corresponds to the peak frequency in the vibration signal.

Here, in order to obtain the rotational frequency of the test object 10, the judgment unit 40 may additionally use other information. For example, as shown in FIG. 4, the test device 20 may be equipped with a rotational speed sensor that detects the rotational speed of the test device 20 (e.g., the rotational speed of the roller 32), and the judgment unit 40 may use this rotational speed. By using the rotational speed in combination, the rotational frequency of the test object 10 can be determined with high accuracy. Note that the rotational speed sensor is not shown in FIG. 2, but a person skilled in the art can attach a rotational speed sensor as appropriate.

Then, the judgment unit 40 estimates the state of the test object 10 based on the rotation frequency of the test object 10. As shown in FIG. 4, the state of the test object 10 includes the type of the test object 10, the maintenance state of the test object 10, and the mounting state of the test object 10.

The type of the test object 10 represents, for example, at least one of the model of the test object 10, the diameter of the wheels 12, the specifications of the motor used in the test object 10, etc. In order to estimate the type of the test object 10, the determination unit 40 may further include a classification unit (not shown).

The maintenance status of the test object 10 indicates, for example, whether the maintenance of the test object 10 completed before the test was performed correctly.

The mounting state of the test object 10 represents, for example, the way in which the test object 10 is "mounted" on the test device 20, and in a more specific example, represents the positional relationship between the test object 10 and the test device 20. More specifically, it may represent the positional relationship between the wheels 12 and the rollers 32.

A specific method for estimating the state of the test object 10 can be designed as appropriate by a person skilled in the art. For example, a known classifier or clustering method may be used. The input and output format of data related to classification or clustering can also be designed as appropriate by a person skilled in the art. Furthermore, a rule-based estimation method may be used, not limited to those using machine learning. Furthermore, in the estimation, appropriate corrections may be made depending on the output of the first vibration sensor 33.

The test device 20 may additionally use other information to estimate the state of the test object 10. For example, as shown in FIG. 4, the positional displacement of the test object 10 relative to the test device 20 may be used.

The positional displacement can be obtained based on at least one of the damper load detected by the test object holding unit load measurement sensor 35, the image captured by the imaging device 36, the rotational speed of the test device 20 detected by the rotational speed sensor, etc. By using the positional displacement in combination, the state of the test object 10 can be estimated with high accuracy.

In this way, the state of the test object 10 is estimated in step S2.

Next, the determination unit 40 acquires the output of the second vibration sensor 34 (step S3). This output is a vibration signal representing the vibration. The vibration signal may be acquired via an amplifier or filter (not shown).

After step S3, the judgment unit 40 judges whether the connection between the test object 10 and the test device 20 is normal or not based on the state of the test object 10 estimated in step S2 and the output of the second vibration sensor 34 acquired in step S3 (step S4).

In this step S4, as shown in FIG. 4, the determination unit 40 first obtains the rotation frequency of the test device 20 based on the output (vibration signal) of the second vibration sensor 34. The rotation frequency of the test device 20 is, for example, the rotation frequency of the roller 32, and corresponds to the peak frequency in the vibration signal.

Then, the judgment unit 40 estimates the state of the test device 20 based on the rotation frequency of the test device 20. The state of the test device 20 includes, for example, at least one of the operating state and the maintenance state of the test device 20. The operating state of the test device 20 indicates, for example, the rotation speed of the roller 32, the force applied to a specific part of the test device 20, etc. The maintenance state of the test device 20 indicates, for example, whether the maintenance of the test device 20 completed before the test was performed correctly.

A specific method for estimating the state of such a test device 20 can be designed as appropriate by a person skilled in the art. For example, a known classifier or clustering method may be used. The input and output format of data related to classification or clustering can also be designed as appropriate by a person skilled in the art. In addition, a rule-based estimation method may be used, not limited to those using machine learning. Furthermore, in the estimation, appropriate corrections may be made depending on the output of the second vibration sensor 34.

In addition, to estimate the state of the test device 20, the determination unit 40 may additionally use the type of the test object 10 estimated in step S2. By using the type of the test object 10, the state of the test device 20 can be estimated with higher accuracy.

The determination unit 40 performs a connection determination based on the state of the test device 20 thus estimated and the state of the test object 10 estimated in step S2. As a more specific example, the determination is performed based on the state of the test device 20, the maintenance state of the test object 10, and the mounting state of the test object 10. In this manner, step S4 is completed.

The specific method of judgment in step S4 can be designed as appropriate by those skilled in the art. For example, a known classifier or clustering method may be used. The input and output format of data related to classification or clustering can also be designed as appropriate by those skilled in the art. In addition, a rule-based estimation method may be used, not limited to those using machine learning. Furthermore, in the estimation, appropriate corrections may be made depending on the output of the first vibration sensor 33 and/or the second vibration sensor 34.

In addition, in this embodiment, the connection between the test object 10 and the test device 20 includes two connection modes as shown in FIG. 1, but the judgment regarding the connection can be made in any unit. In other words, it is possible to design the device so that the judgment is made comprehensively without distinguishing between the two connection modes, or to make a judgment for each connection mode and make a final judgment based on the judgment results.

To make the judgment in step S4, the judgment unit 40 may further include a diagnosis unit (not shown).

Next, the determination unit 40 outputs the result of the determination (step S5). The output may be, for example, to the storage means 42 of the determination unit 40, to an output device (such as a display or a printer) of the determination unit 40, or to another computer via a communication network.

As described above, the test device 20 according to the first embodiment of the present invention can appropriately determine whether the connection between the test object 10 and the test device 20 is normal or not.

In particular, since the judgment is made using the vibration of the test device 20 in addition to the vibration of the test object 10, it is possible to make a more accurate judgment than a judgment based only on the vibration of the test object 10. More specifically, the rotation frequency of the test device 20 can be used.

The judgment unit 40 performs judgments automatically, so there is no need for the operator to become familiar with the structure and behavior of the testing equipment, and more appropriate judgments can be made in a wider range of tests.

The judgment unit 40 estimates the type of the test object 10 during the judgment process, so the judgment criteria can be appropriately changed depending on the type of the test object 10. Note that although specific examples of judgment criteria for each type are not specifically shown, they can be substantially realized, for example, by a classifier or a clustering method.

When the test device 20 is equipped with a test object holding section load measurement sensor 35, the judgment section 40 further estimates the state of the test object 10 based on the damper load, so that the positional displacement of the test object 10 can be taken into account, improving the accuracy of the estimation.

If the test device 20 is equipped with an imaging device 36, the judgment unit 40 further estimates the state of the test object 10 based on the image, so that the positional displacement of the test object 10 can be taken into account, improving the accuracy of the estimation.

If the test device 20 is equipped with an additional rotation speed sensor, the judgment unit 40 further judges whether the connection between the test object 10 and the test device 20 is normal or not based on the rotation speed of the roller 32, thereby improving the accuracy of the judgment.

The test device 20 includes a roller 32, and the roller 32 is connected to the wheel 12, so that the rotation frequency of the roller 32 can be used to determine the connection, improving the accuracy of the determination. In addition, by attaching a second vibration sensor 34 in relation to the roller 32, the rotation frequency of the roller 32 can be appropriately detected.

The judgment unit 40 estimates the mounting state as the state of the test object 10, so it can take into account misalignment when mounting the test object 10 on the test device 20, improving the accuracy of the judgment.

The judgment unit 40 uses the rotation frequency of the test object 10 when estimating the state of the test object 10, so the state can be estimated with high accuracy.

The judgment unit 40 estimates the maintenance state as the state of the test object 10, so if the connection is normal, it can judge whether the maintenance of the test object 10 has been performed correctly, just like conventional testing devices.

The device body 30 is equipped with a fixing device 31, so that the test object 10 can be properly fixed and connected. In particular, it is possible to determine whether the connection between the fixing device 31 and the frame 11 is proper or not. Furthermore, when the first vibration sensor 33 is attached to the fixing device 31, it is possible to properly detect the vibration of the test object 10.

The following modifications can be made to the above-described embodiment 1:

The execution timing of each step shown in FIG. 3 is not limited to that shown in FIG. 3. For example, the execution timing of step S3 may be before step S1, or between step S1 and step S2.

In addition, steps S2 and S4 may be executed in parallel. In that case, as shown in FIG. 4, the state of the test device 20 may first be estimated based on the type of test object 10, and then the state of the test device 20 may be referenced when estimating the maintenance state and mounting state of the test object 10.

The determination unit 40 may automatically determine the timing to execute the process of FIG. 3. For example, in steps S1 and S3, the period during which the output of the first vibration sensor 33 and the second vibration sensor 34 is acquired may be determined. In particular, the time at which the rotational speed of the wheel 12 and the roller 32 is constant may be determined based on the RMS (root mean square) of the vibration of each sensor, and the output of each sensor during a predetermined period including that time may be used. With this configuration, the progress of the process of FIG. 3 can be controlled without using a rotational speed sensor.

The mounting positions of each sensor are not limited to those shown in FIG. 2, and can be any position. Here, it is preferable to mount the first vibration sensor 33 at a position where the rotational frequency of the test object 10 is strongly transmitted. Similarly, it is preferable to mount the second vibration sensor 34 at a position where the rotational frequency of the test device 20 is strongly transmitted.

As shown in FIG. 4, the test object holder load measurement sensor 35, the image capture device 36, and the rotational speed sensor can be omitted. If any of them are omitted, the judgment in step S4 can be made without using the information obtained from them.

The rotation speed sensor may be omitted, and the rotation speed of the test device 20 may be estimated based on the output of the first vibration sensor 33 or the second vibration sensor 34. In this way, the number of sensors can be reduced while still utilizing the rotation speed, thereby improving the accuracy of the determination while keeping costs down. In addition, the reduced number of sensors reduces the failure rate of the test device 20.

The test device 20 may further include other types of additional sensors. For example, it may include a microphone for detecting voice, a displacement meter for detecting the positional displacement of the test object 10, a ToF sensor (time-of-flight sensor), a temperature sensor, etc.

The rollers 32 may be omitted. In that case, other structures may be provided to properly rotate the wheels 12.

Specific examples of the state of the test object 10 are not limited to those shown in FIG. 4. Furthermore, the state of the test object 10 does not have to include the three types of states as shown in FIG. 4, and may include any one or two. In particular, when the maintenance state of the test object 10 is not estimated as the state of the test object 10, the estimation of the maintenance state may be performed by a test device other than the test device 20.

10: Test object 11: Frame 12: Wheel 20: Test device 30: Device body 31: Fixture 32: Roller (rotating structure)
33: First vibration sensor 34: Second vibration sensor 35: Test object holder load measurement sensor (sensor for detecting damper load)
36: Imaging device 37: Shaft 40: Determination unit 41: Calculation means 42: Storage means

Claims (13)

1. A test device for testing a test object comprising a rotating wheel, the device comprising:
a first vibration sensor for detecting vibrations of the test object;
a second vibration sensor for detecting vibration of the testing apparatus;
A determination unit;
Equipped with
The determination unit estimates a state of the test object based on an output of the first vibration sensor,
The determination unit determines whether or not a connection between the test object and the testing device is normal based on a state of the test object and an output of the second vibration sensor.
Test equipment. the testing device includes a sensor for detecting a damper load in the testing device;
The determination unit further estimates a state of the test object based on the damper load.
2. The test device of claim 1. the test apparatus includes an imaging device for acquiring an image including at least a portion of the test object;
The determination unit further estimates a state of the test object based on the image.
2. The test device of claim 1. The test device includes a rotating structure that rotates in relation to the rotation of the wheel;
the second vibration sensor is attached to the rotating structure;
The determination unit obtains a rotation frequency of the rotating structure based on an output of the second vibration sensor, and estimates a state of the test object based on a rotation frequency of the test apparatus.
2. The test device of claim 1. The test device includes a rotating structure that rotates in relation to the rotation of the wheel;
the connection includes a connection between the wheel and the rotating structure;
2. The test device of claim 1. The test device includes a rotating structure that rotates in relation to the rotation of the wheel;
the test device includes a rotation speed sensor that detects a rotation speed of the rotating structure;
The determination unit further determines whether or not a connection between the test object and the test device is normal based on the rotation speed of the rotation structure.
2. The test device of claim 1. The test device of claim 1, wherein the condition of the test object includes the type of the test object. The test device according to claim 1, wherein the state of the test object includes a mounting state of the test object on the test device. The test device of claim 1, wherein the condition of the test object includes a maintenance condition of the test object. The testing apparatus includes a frame for fixedly supporting a portion of the test object;
the test object includes an axle for rotatably supporting the wheel, and the connection includes a connection between the frame and the axle;
2. The test device of claim 1. The testing apparatus includes a frame for fixedly supporting a portion of the test object;
the first vibration sensor is attached to the frame;
2. The test device of claim 1. The test device according to claim 1, wherein the determination unit obtains the rotation frequency of the test object based on the output of the first vibration sensor, and estimates the state of the test object based on the rotation frequency of the test object. A test method for testing a test object having a rotating wheel by a test device having a judgment unit, comprising:
The determination unit estimates a state of the test object based on an output of a first vibration sensor for detecting vibration of the test object;
determining whether or not a connection between the test object and the test device is normal based on the state of the test object estimated by the determination unit and an output of a second vibration sensor for detecting vibration of the test device;
A method comprising:

Images