A method and apparatus for testing a clutch

Abstract

The application discloses a kind of clutch test methods, first increase the target pressure of R clutch, so that the first speed difference between the speed of engine and the speed of turbine gradually increases.When the first speed difference reaches the first preset threshold, stop increasing the target pressure of R clutch, the target pressure of R clutch corresponding at this time is regarded as the half combination point KP of R clutch.Value.Keep the target pressure on R clutch unchanged, start gradually increasing the target pressure on TC clutch, in this case, the second speed difference between the speed of engine and the speed of turbine gradually decreases.When the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold, the target pressure on TC clutch at this time is regarded as the KP of TC clutch, and the test of TC clutch KP is completed. That is, by the technical scheme provided in the application, the acquisition of two clutch KP values is completed by one test, the test time is effectively shortened, and the production efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of clutch control technology, specifically to a clutch testing method and apparatus. Background Technology

[0002] As a key component in automotive power transmission, the clutch's control precision not only affects the comfort of power delivery but also the vehicle's lifespan. Typically, the clutch maintains control precision through self-learning during vehicle operation, based on its partial engagement (Kiss Point, KP) characteristics. The clutch's KP point refers to the piston pressure required to overcome the release spring force and begin pressing the friction plates and steel plates together.

[0003] Currently, the KP points of the reverse clutch (R clutch) and the torque converter (TC) clutch in a continuously variable transmission (CVT) are obtained through separate testing. This method results in low production line efficiency due to the long testing time. Summary of the Invention

[0004] In view of this, the present application provides a clutch testing method and apparatus that can obtain the KP values ​​of two clutches in one test, thereby shortening the overall testing time and improving production efficiency.

[0005] To address the above problems, the technical solutions provided in this application are as follows:

[0006] In a first aspect of this application, a clutch testing method is provided, the method being applied to a controller, comprising:

[0007] Increase the target pressure of the R clutch to increase the first speed difference between the engine speed and the turbine speed;

[0008] When the first speed difference reaches the first preset threshold, the target pressure of the R clutch corresponding to the first speed difference reaching the first preset threshold is taken as the half engagement point KP value of the R clutch.

[0009] While keeping the target pressure on the R clutch constant, the target pressure on the TC clutch is increased to reduce the second speed difference between the engine speed and the turbine speed.

[0010] When the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold, the target pressure of the TC clutch is taken as the KP value of the TC clutch.

[0011] In a second aspect of this application, a clutch testing device is provided, the device being applied to a controller, comprising:

[0012] The control unit is used to increase the target pressure of the R clutch so as to increase the first speed difference between the engine speed and the turbine speed;

[0013] The acquisition unit is used to take the target pressure of the R clutch corresponding to the first speed difference reaching the first preset threshold as the half engagement point KP value of the R clutch when the first speed difference reaches the first preset threshold.

[0014] The control unit is further configured to increase the target pressure of the TC clutch while keeping the target pressure on the R clutch constant, so as to reduce the second speed difference between the engine speed and the turbine speed.

[0015] The acquisition unit is further configured to use the target pressure of the TC clutch as the KP value of the TC clutch when the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold.

[0016] In a third aspect of this application, a controller is provided, including: a processor and a memory;

[0017] The memory is used to store computer-readable instructions or computer programs;

[0018] The processor is configured to read the computer-readable instructions or the computer program to enable the electronic device to implement the clutch testing method described in the first aspect.

[0019] In a fourth aspect of this application, a vehicle is provided, the vehicle including the controller, R clutch and TC clutch described in the second or third aspect;

[0020] The controller is used to acquire the KP value of the R clutch and the KP value of the TC clutch.

[0021] In a fifth aspect of this application, a computer-readable storage medium is provided, wherein instructions are stored therein, which, when executed on a device, cause the device to perform the clutch testing method described in the first aspect.

[0022] In a sixth aspect of this application, a computer program product is provided that, when the computer program product is run on a computer, causes the computer to perform the clutch testing method described in the first aspect.

[0023] Therefore, the embodiments of this application have the following beneficial effects:

[0024] In this application, the target pressure of clutch R is first increased, thereby gradually increasing the first speed difference between the engine speed and the turbine speed. When the first speed difference reaches a first preset threshold, the increase in the target pressure of clutch R is stopped, and the target pressure corresponding to clutch R at this point is taken as the half-engagement point KP value of clutch R, thus completing the test of clutch R's KP value. Keeping the target pressure on clutch R constant, the target pressure on clutch TC is gradually increased. Under this condition, the second speed difference between the engine speed and the turbine speed gradually decreases. When the absolute value of the difference between the first and second speed differences equals a second preset threshold, the target pressure on clutch TC at this point is taken as the KP value of clutch TC, completing the test of clutch TC's KP value. That is, the technical solution provided in this application enables the acquisition of KP values ​​for two clutches in a single test, effectively shortening testing time and improving production efficiency. Attached Figure Description

[0025] Figure 1a A schematic diagram illustrating the acquisition of the KP value for an R-clutch;

[0026] Figure 1b This is a schematic diagram illustrating the acquisition of the KP value for a TC clutch.

[0027] Figure 2 A flowchart of a clutch testing method provided in an embodiment of this application;

[0028] Figure 3 A framework diagram for obtaining the KP value of two clutches is provided in an embodiment of this application;

[0029] Figure 4 A structural diagram of a clutch testing device provided in an embodiment of this application;

[0030] Figure 5 A controller structure diagram provided for an embodiment of this application;

[0031] Figure 6 This is a vehicle structure diagram provided for an embodiment of this application. Detailed Implementation

[0032] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the embodiments of this application will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0033] The inventors of this application discovered through research that the KP values ​​of the R clutch and the TC clutch are currently mainly obtained through separate testing. The advantage of this method is that it allows for separate testing based on their respective characteristics; the disadvantage is that it requires two tests and the testing time is long. During testing on the production line, the increased testing time directly impacts production efficiency.

[0034] In the separate testing method, the process of obtaining the KP value by the R clutch is as follows: Figure 1a As shown. (Through) Figure 1a It can be seen that as the target pressure L3 of clutch R increases, at time t0, the engine speed L1 and turbine speed L2 begin to separate. At time t1, the turbine speed L2 begins to stabilize. After stabilizing for a period of time, the target pressure on clutch L3 is read at time t2 and used as the KP value of clutch R.

[0035] The process of obtaining the KP value by the TC clutch is as follows: Figure 1b As shown, the target pressure of clutch R (L3) is first increased to gradually separate the engine speed (L1) and turbine speed (L2). At time t1, the turbine speed (L2) stabilizes. Maintaining the target pressure value on clutch R (L3) unchanged, the target pressure on clutch TC (L4) is increased. From time t2, the turbine speed (L2) is pulled up by the target pressure L4 of clutch TC. At time t3, the turbine speed (L2) stabilizes. The target pressure L4 of clutch TC at this point is then used as the KP value of clutch TC and stored in the EEPROM.

[0036] The KP value is obtained by observing whether the turbine speed is stable. However, in practical applications, phenomena such as turbine vibration may occur, affecting the accuracy of the KP value.

[0037] Based on this, this application sequentially controls the target pressure of the R clutch and the target pressure of the TC clutch, and obtains the KP value of the R clutch and the KP value of the TC clutch respectively according to the speed difference change characteristics. That is, the KP value of both clutches is obtained through a single test, and the speed difference, not the turbine speed, is referenced when obtaining the KP value of the TC clutch, thereby eliminating instability caused by sudden turbine vibration and improving the accuracy of the TC clutch KP value.

[0038] It should be noted that this application applies to automatic transmissions in gasoline vehicles or hybrid transmissions with TC clutch and R clutch drive systems.

[0039] To facilitate understanding of the technical solution of this application, the following description will be provided in conjunction with the accompanying drawings.

[0040] See Figure 2 The figure is a flowchart of a clutch testing method provided in an embodiment of this application, as shown below. Figure 2 As shown, the method includes:

[0041] S201: Increase the target pressure of the R clutch to increase the first speed difference between the engine speed and the turbine speed.

[0042] S202: When the first speed difference reaches the first preset threshold, the target pressure of the R clutch corresponding to the first speed difference reaching the first preset threshold is taken as the KP value of the R clutch.

[0043] In this embodiment, the target pressure of the R clutch can be directly controlled from a certain value, gradually increasing until a certain point is reached where the engine speed and turbine speed begin to separate. As the target pressure continues to increase, the speed difference between the engine speed and turbine speed also gradually increases. It should be noted that during the process of increasing the target pressure of the R clutch, the TC clutch may not have a target pressure or the target pressure may remain constant at a small value. In this case, the engine speed remains constant, while the turbine speed decreases.

[0044] When the first speed difference reaches the first preset threshold, the increase in target pressure stops, and the target pressure value of the R clutch at this time is taken as the KP value of the R clutch, thus completing the acquisition of the KP value of the R clutch. Simultaneously, this KP value can be stored in an electrically erasable programmable read-only memory (EEPROM). The first preset threshold can be set according to actual conditions, and this embodiment does not impose any limitations on it.

[0045] To ensure the accuracy of the KP value, if the first speed difference reaches a first preset threshold and the target pressure on the R clutch remains unchanged, and the first speed difference is maintained at a third preset threshold for a first preset duration, then the KP value test of the R clutch is considered complete. The target pressure corresponding to when the first speed difference reaches the first preset threshold is then taken as the KP value of the R clutch. In other words, by waiting for the speed difference to stabilize for a period of time before obtaining the KP value of the R clutch, the instability of the speed difference caused by turbo vibration is avoided, thus preventing it from affecting the accuracy of the KP value.

[0046] S203: While keeping the target pressure on the R clutch constant, increase the target pressure on the TC clutch to reduce the second speed difference between the engine speed and the turbine speed.

[0047] S204: When the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold, the target pressure of the TC clutch is taken as the KP value of the TC clutch.

[0048] After obtaining the KP value of the R clutch, while keeping the target pressure value on the R clutch constant, the target pressure of the TC clutch is increased to reduce the second speed difference between the engine speed and the turbine speed. It should be noted that as the target pressure of the TC clutch increases, the engine speed remains constant, while the turbine speed gradually increases.

[0049] The increase in the target pressure of the TC clutch reduces the speed difference between the engine speed and the turbine speed. To make the subsequent decrease in speed difference more pronounced, the target pressure value on the R clutch is increased by a preset value before increasing the target pressure of the TC clutch, so that the first speed difference reaches a third preset threshold. The third preset threshold is greater than the first preset threshold; for example, the third preset threshold is 50 rpm and the first preset threshold is 30 rpm.

[0050] After the first speed difference reaches the third preset threshold, keep the target pressure on the R clutch unchanged, and then increase the target pressure on the TC clutch.

[0051] Furthermore, to avoid the turbine vibration affecting the accuracy of the KP value, after the first speed difference reaches the third preset threshold and the first speed difference is maintained at the third preset threshold for a second preset time, the target pressure on the R clutch remains unchanged, and the target pressure on the TC clutch is increased.

[0052] As the target pressure of the TC clutch increases, the second speed difference gradually decreases. When the absolute value of the difference between the first and second speed differences equals the second preset threshold, the target pressure of the TC clutch is taken as the KP value of the TC clutch. Simultaneously, this KP value can be stored in the EEPROM for transmission control.

[0053] It should be noted that during the process of increasing the target pressure of the TC clutch, the second speed difference remains unchanged during the first time period. During the second time period, as the target pressure of the TC clutch continues to increase, the second speed difference begins to gradually decrease. The end time of the first time period equals the start time of the second time period; from the start of the second time period, the second speed difference gradually decreases as the target pressure increases.

[0054] As can be seen, this method enables the acquisition of KP values ​​for two clutches in a single test, effectively shortening testing time and improving production efficiency. Furthermore, when acquiring the KP value of the TC clutch, the absolute value of the speed difference between the two clutches is used as a reference, avoiding the impact of turbine vibration on the accuracy of the KP value and improving control precision.

[0055] For a better understanding of the overall implementation of this application, please refer to [link / reference]. Figure 3 The diagram shows how to obtain the clutch KP value.

[0056] (1) t0-t1 time: KP test is activated, R clutch target pressure L3 is directly controlled from a certain value (0.1 bar lower than the lower limit boundary of KP hardware design), and the target pressure is gradually increased. When t1 time is reached, engine speed L1 and turbine speed L2 begin to separate.

[0057] (2) t1-t2: As the target pressure L3 of the R clutch continues to increase, the speed difference between the engine and the turbine gradually increases. When the speed difference reaches a certain threshold (30 rpm), i.e. t2, the increase of the target pressure stops.

[0058] (3) t2-t3: After the target pressure L3 of clutch R stops increasing, wait for the speed difference to stabilize for a period of time (40ms), then confirm that the acquisition of the KP value of clutch R is complete and store it in EEPROM L5. The stored value is the target pressure of clutch R at this time. After that, the target pressure is immediately increased by an offset (0.05bar); by increasing the offset, the speed difference is increased so as to observe the trend of the speed difference increase in the future.

[0059] (4) t3-t4: As the target pressure L3 of the R clutch increases, the speed difference further separates and reaches a certain threshold (50 rpm);

[0060] (5) t4-t5 time: wait for the speed difference to stabilize for a certain period of time (500ms), and when t5 time is reached, record the speed difference SpdDiff_t5 at this time. At this time, the target pressure L4 of TC clutch starts to control and gradually increases.

[0061] (6) t5-t6: During this process, the target pressure L4 of the TC clutch begins to increase, and when it reaches t6, the speed difference begins to decrease.

[0062] (7) t6-t7: As the target pressure of the TC clutch continues to increase, the speed difference further decreases. When the absolute value of the difference between the speed difference at this time and the speed difference at SpdDiff_t5 is greater than a certain threshold (25rpm), it is confirmed that the TC clutch KP value has been obtained, and this TC clutch target pressure is recorded in EEPROM L6. At t7, the target pressures of the TC clutch and the R clutch are restored to their initial state.

[0063] The time period t5-t6 is the first time period, and the time period t6-t7 is the second time period.

[0064] (8) t7-t8 time: After the target pressure of the two clutches returns to the initial state, the speed difference between the engine and the turbine quickly shrinks and returns to the original state. After waiting for a certain period of time (800ms) to stabilize, the test is completed at time t8.

[0065] According to the above technical solution, the KP value characteristics of two clutches can be obtained in one test, which shortens the overall test time.

[0066] Based on the above method embodiments, this application provides a clutch testing device, which will be described below with reference to the accompanying drawings.

[0067] See Figure 4 The figure shows a clutch testing device provided in an embodiment of this application. The device 400 may include a control unit 401 and an acquisition unit 402.

[0068] Control unit 401 is used to increase the target pressure of the R clutch so as to increase the first speed difference between the engine speed and the turbine speed;

[0069] The acquisition unit 402 is used to take the target pressure of the R clutch corresponding to the first speed difference reaching the first preset threshold as the half engagement point KP value of the R clutch when the first speed difference reaches the first preset threshold.

[0070] The control unit 401 is further configured to increase the target pressure of the TC clutch while keeping the target pressure on the R clutch constant, so as to reduce the second speed difference between the engine speed and the turbine speed.

[0071] The acquisition unit 402 is further configured to use the target pressure of the TC clutch as the KP value of the TC clutch when the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold.

[0072] Increase the target pressure of the R clutch to increase the first speed difference between the engine speed and the turbine speed;

[0073] When the first speed difference reaches the first preset threshold, the target pressure of the R clutch corresponding to the first speed difference reaching the first preset threshold is taken as the half engagement point KP value of the R clutch.

[0074] While keeping the target pressure on the R clutch constant, the target pressure on the TC clutch is increased to reduce the second speed difference between the engine speed and the turbine speed.

[0075] When the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold, the target pressure of the TC clutch is taken as the KP value of the TC clutch.

[0076] In some embodiments, the acquisition unit 402 is specifically used to, when the first speed difference reaches a first preset threshold and the target pressure on the R clutch remains unchanged, if the first speed difference is maintained at the first preset threshold for a first preset duration, take the target pressure of the R clutch corresponding to the first speed difference reaching the first preset threshold as the KP value of the R clutch.

[0077] In some embodiments, the control unit 401 is specifically used to increase the target pressure value on the R clutch by a preset pressure value so that the first speed difference reaches a third preset threshold; after the first speed difference reaches the third preset threshold, the target pressure on the R clutch remains unchanged, and the target pressure on the TC clutch is increased.

[0078] In some embodiments, the control unit 401 is specifically used to maintain the target pressure on the R clutch unchanged and increase the target pressure on the TC clutch after the first speed difference reaches the third preset threshold and the first speed difference is maintained at the third preset threshold for a second preset duration.

[0079] In some embodiments, the control unit 401 is specifically configured to increase the target pressure of the TC clutch during a first time period while keeping the second speed difference unchanged; and to continue increasing the target pressure of the TC clutch during a second time period while gradually decreasing the second speed difference, wherein the end time of the first time period is equal to the start time of the second time period.

[0080] In some embodiments, the device further includes: a storage unit;

[0081] The storage unit is used to store the KP value of the R clutch and / or the KP value of the TC clutch in the EEPROM.

[0082] It should be noted that the information execution process of each unit in the above-mentioned device can be found in the description of the method embodiment shown in the foregoing of this application, and will not be repeated here.

[0083] In addition, embodiments of this application provide a controller, such as Figure 5 As shown, the controller 500 includes: a memory 501 and a processor 502;

[0084] The memory 501 is used to store computer-readable instructions or computer programs;

[0085] The processor 502 is configured to read the computer-readable instructions or the computer program so that the device implements the clutch testing method.

[0086] This application also provides a vehicle, such as... Figure 6 As shown, the vehicle 600 includes a controller 601, an R clutch 602, and a TC clutch 603.

[0087] Among them, controller 600 can be Figure 4 The device 400 in the embodiment or Figure 5 The controller 500 in the embodiment is used to execute... Figure 2The method is used to obtain the KP values ​​of R clutch 602 and TC clutch 603.

[0088] This application provides a computer-readable storage medium, including instructions or a computer program, which, when run on a computer, causes the computer to perform the clutch testing method described above.

[0089] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0090] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0091] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0092] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0093] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A clutch testing method, characterized in that, The method is applied to a controller and includes: Increase the target pressure of the reverse clutch to increase the first speed difference between the engine speed and the turbine speed; When the first speed difference reaches the first preset threshold, the target pressure of the reverse clutch corresponding to when the first speed difference reaches the first preset threshold is taken as the value of the half engagement point of the reverse clutch. While keeping the target pressure on the reverse clutch constant, the target pressure on the torque converter clutch is increased so that the second speed difference between the engine speed and the turbine speed is reduced. When the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold, the target pressure of the hydraulic torque converter clutch is taken as the value of the half engagement point of the hydraulic torque converter clutch.

2. The method according to claim 1, characterized in that, When the first speed difference reaches a first preset threshold, the target pressure of the reverse clutch corresponding to when the first speed difference reaches the first preset threshold is taken as the value of the half-engagement point of the reverse clutch, including: When the first speed difference reaches the first preset threshold and the target pressure on the reverse clutch remains unchanged, if the first speed difference is maintained at the first preset threshold for a first preset duration, the target pressure of the reverse clutch corresponding to when the first speed difference reaches the first preset threshold is taken as the value of the half engagement point of the reverse clutch.

3. The method according to claim 1 or 2, characterized in that, Increasing the target pressure of the torque converter clutch while keeping the target pressure on the reverse clutch constant includes: Increase the target pressure value on the reverse clutch by a preset pressure value so that the first speed difference reaches a third preset threshold. After the first speed difference reaches the third preset threshold, the target pressure on the reverse clutch remains unchanged, and the target pressure of the torque converter clutch is increased.

4. The method according to claim 3, characterized in that, After the first speed difference reaches the third preset threshold, maintaining the target pressure on the reverse clutch unchanged and increasing the target pressure on the torque converter clutch includes: After the first speed difference reaches the third preset threshold and the first speed difference is maintained at the third preset threshold for a second preset time, the target pressure on the reverse clutch remains unchanged, and the target pressure of the hydraulic torque converter clutch is increased.

5. The method according to claim 1 or 2, characterized in that, While keeping the target pressure on the reverse clutch constant, increasing the target pressure on the torque converter clutch includes: During the first time period, the target pressure of the hydraulic torque converter clutch is increased while the second speed difference remains unchanged; During the second time period, the target pressure of the hydraulic torque converter clutch continues to increase, the second speed difference gradually decreases, and the end time of the first time period is equal to the start time of the second time period.

6. The method according to claim 1, characterized in that, The method further includes: The EEPROM stores the value of the half-engagement point of the reverse clutch and / or the value of the half-engagement point of the torque converter clutch.

7. A clutch testing device, characterized in that, The device is applied to a controller and includes: The control unit is used to increase the target pressure of the reverse clutch so as to increase the first speed difference between the engine speed and the turbine speed; The acquisition unit is used to take the target pressure of the reverse clutch corresponding to the first speed difference reaching the first preset threshold as the value of the half engagement point of the reverse clutch when the first speed difference reaches the first preset threshold. The control unit is further configured to increase the target pressure of the torque converter clutch while keeping the target pressure on the reverse clutch constant, so as to reduce the second speed difference between the engine speed and the turbine speed. The acquisition unit is further configured to use the target pressure of the hydraulic torque converter clutch as the value of the half-engagement point of the hydraulic torque converter clutch when the absolute value of the difference between the first speed difference and the second speed difference is equal to the second preset threshold.

8. A controller, characterized in that, The controller includes: a memory and a processor; The memory is used to store computer-readable instructions or computer programs; The processor is configured to read the computer-readable instructions or the computer program so that the controller executes the clutch testing method according to any one of claims 1-6.

9. A vehicle, characterized in that, The vehicle includes the controller, reverse clutch, and torque converter clutch as described in claim 7 or claim 8; The controller is used to obtain the value of the half-engagement point of the reverse gear clutch and the value of the half-engagement point of the torque converter clutch.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed on the device, cause the device to perform the clutch testing method according to any one of claims 1-6.

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