Clutch feature point self-learning method and device, equipment and storage medium

Abstract

The embodiment of the invention discloses a clutch feature point self-learning method, device and equipment and a storage medium, and belongs to the technical field of clutches. The method disclosed by the embodiment of the invention generally comprises a self-learning trigger judgment step, a clutch separation point determination step, a clutch friction point determination step and a clutch combination point determination step, parameters such as intermediate shaft braking torque, speed reduction resistance torque of a transmission input shaft rotating system and clutch transmission torque are introduced in the clutch feature point self-learning process, so that the self-learning precision of clutch feature points such as a clutch separation point, a clutch friction point and a clutch combination point can be improved; and the problems of slow vehicle starting, poor smoothness and the like caused by too high learning values of the friction points and the separation points can be relieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of clutches, and in particular, to a method, device, equipment and storage medium for self-learning clutch characteristic points. Background Art

[0002] Currently, the existing self-learning of clutch characteristic points is mainly based on the separation and engagement processes of the clutch, and its accuracy can meet the vast majority of actual application scenarios.

[0003] However, in some special scenarios (such as when the resistance of the transmission input shaft and related rotating systems is small, or when the input shaft front bearing transmits a certain engine flywheel torque, etc.), the existing self-learning of clutch characteristic points does not consider factors such as clutch transmitted torque and intermediate shaft brake resistance. As a result, the learned values of the friction point and separation point are too high, which easily leads to problems such as slow and uneven vehicle starting.

[0004] Specifically, the self-learning method involved in the existing patent document 1 (CN114330492A) at least does not consider the clutch transmitted torque; the existing patent document 2 (CN113007239A) only introduces the self-learning method of the clutch friction point, and at least does not introduce the intermediate shaft brake resistance during the self-learning process. When the transmission system resistance is small, the learning accuracy is poor. Summary of the Invention

[0005] The embodiments of the present invention provide a method, device, equipment and storage medium for self-learning clutch characteristic points, so as to consider at least factors such as clutch transmitted torque and intermediate shaft brake resistance during the self-learning process of clutch characteristic points, improve the learning accuracy of self-learning clutch characteristic points, and help alleviate problems such as slow vehicle starting and poor smoothness.

[0006] In a first aspect, the embodiments of the present invention provide a method for self-learning clutch characteristic points, which at least includes the following steps:

[0007] S1. When the vehicle is in a preset state, in response to a preset operation, a self-learning command is triggered. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of clutch characteristic points is started;

[0008] S2. Control the clutch to disengage at a preset speed. When the clutch disengages to a preset separation position, the intermediate shaft brake is turned on to keep the intermediate shaft braking torque at a preset torque;

[0009] S3. Control the clutch to continue to disengage at the preset speed until the transmission input shaft speed drops by a preset speed difference, record the first clutch position, and obtain the clutch separation point according to the preset clutch torque-position curve and the first clutch position;

[0010] S4. Control the clutch to continue separating at the maximum speed until the rotational speed of the transmission input shaft drops to a preset rotational speed point, record the deceleration rate of the transmission input shaft at this time, and calculate the deceleration resistance torque of the input shaft rotation system according to the deceleration rate of the transmission input shaft and the preset moment of inertia.

[0011] S5. After the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to work at the preset torque and make the clutch engage at the preset speed until the rotational speed of the transmission input shaft rises to the preset rotational speed point, record the acceleration rate of the transmission input shaft and the position of the second clutch, and calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque.

[0012] S6. Determine the clutch friction point according to the preset clutch torque-position curve and the position of the second clutch.

[0013] S7. Release the intermediate shaft braking torque, control the clutch exhaust valve to be fully open and keep it for a first preset time, and record the position of the third clutch, which is the clutch engagement point.

[0014] Optionally, it further includes:

[0015] S8. When the vehicle is in gear and the clutch is fully engaged during driving, control the clutch exhaust valve to be fully open once every second preset time, and keep the clutch exhaust valve fully open within the first preset time. Also record the position of the clutch at this time as the position of the third clutch, which is also the clutch engagement point.

[0016] Optionally, the vehicle being in a preset state at least means that the vehicle's transmission is in neutral, the clutch is in the engaged position, the engine is idling, and the rotational speed of the transmission input shaft is equal to the engine idle speed.

[0017] The preset operation at least refers to the operation of the driver shifting from the forward gear to neutral.

[0018] The self-learning conditions at least include one of the air source pressure being within a first preset range, the engine speed being within a second preset range, the transmission oil temperature being within a third preset range, the clutch temperature being within a fourth preset range, and the output shaft speed being within a fifth preset range.

[0019] Optionally, step S3 at least includes:

[0020] Control the clutch to continue to disengage at the preset speed until the rotational speed of the transmission input shaft drops by the preset rotational speed difference, record the first clutch position, and calculate the first position difference between when the clutch transmits zero torque and when it transmits the preset torque according to the preset clutch torque-position curve, so as to obtain the clutch disengagement point based on the first clutch position and the first position difference.

[0021] Optionally, step S5 at least includes:

[0022] After the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to work at the preset torque and make the clutch engage at the preset speed until the rotational speed of the transmission input shaft rises to the preset rotational speed point, record the rotational speed increase rate of the transmission input shaft and the second clutch position, calculate the rotational speed increase torque of the input shaft rotating system based on the preset moment of inertia and the rotational speed increase rate of the transmission input shaft, and then calculate the torque transmitted by the clutch according to the rotational speed increase torque and the rotational speed decrease resistance torque.

[0023] Optionally, step S6 at least includes:

[0024] Calculate the second position difference between when the clutch transmits the preset friction point torque and when it transmits the torque transmitted by the clutch according to the preset clutch torque-position curve, so as to determine the clutch friction point based on the second position difference and the second clutch position.

[0025] Optionally, the preset clutch torque-position curve is at least obtained by testing the average value of the torque curves transmitted by clutches with a set number of samples at different positions when the samples come off the production line.

[0026] In a second aspect, an embodiment of the present invention further provides a clutch characteristic point self-learning device, which at least includes:

[0027] A self-learning trigger module, configured to, when the vehicle is in a preset state, trigger a self-learning command in response to a preset operation, and if it is further determined that the vehicle meets the self-learning conditions, start the self-learning of the clutch characteristic points;

[0028] A first control module, configured to control the clutch to disengage at a preset speed. When the clutch disengages to a preset disengagement position, turn on the intermediate shaft brake so that the intermediate shaft braking torque remains at a preset torque;

[0029] A second control module, configured to control the clutch to continue to disengage at the preset speed until the rotational speed of the transmission input shaft drops by a preset rotational speed difference, record the first clutch position, and obtain the clutch disengagement point according to the preset clutch torque-position curve and the first clutch position;

[0030] A third control module, configured to control the clutch to continue separating at the maximum speed until the rotational speed of the transmission input shaft drops to a preset speed point, record the deceleration rate of the transmission input shaft at this time, and calculate the deceleration resistance torque of the input shaft rotation system according to the deceleration rate of the transmission input shaft and a preset moment of inertia;

[0031] A fourth control module, configured to, after the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to operate at the preset torque and make the clutch engage at the preset speed until the rotational speed of the transmission input shaft rises to the preset speed point, record the acceleration rate of the transmission input shaft and the second clutch position, and calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque;

[0032] A friction point determination module, configured to determine the clutch friction point according to the preset clutch torque-position curve and the second clutch position;

[0033] A fifth control module, configured to release the intermediate shaft braking torque, control the clutch exhaust valve to be fully open and continue for a first preset time, and record the third clutch position as the clutch engagement point.

[0034] In a third aspect, an embodiment of the present invention further provides an electronic device, including a processor and a memory, where the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the steps in the clutch characteristic point self-learning method described in the first aspect are run.

[0035] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the steps in the clutch characteristic point self-learning method described in the first aspect are implemented.

[0036] For the technical solution provided by the embodiments of the present invention, first, when the vehicle is in a preset state, in response to a preset operation, a self-learning command is triggered. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of the clutch characteristic points is started; further, the clutch is controlled to disengage at a preset speed. When the clutch disengages to a preset disengagement position, the intermediate shaft brake is turned on to keep the intermediate shaft braking torque at a preset torque; further, the clutch is controlled to continue to disengage at a preset speed until the rotational speed of the transmission input shaft drops by a preset rotational speed difference, and the first clutch position is recorded. The clutch disengagement point is obtained according to the preset clutch torque-position curve and the first clutch position; further, the clutch is controlled to continue to disengage at the maximum speed until the rotational speed of the transmission input shaft drops to a preset rotational speed point, and the deceleration rate of the transmission input shaft is recorded. The deceleration resistance torque of the input shaft rotating system is calculated according to the deceleration rate of the transmission input shaft and the preset moment of inertia; further, after the rotational speed of the transmission input shaft drops to zero, the intermediate shaft brake is controlled to work at a preset torque and the clutch is controlled to engage at a preset speed until the rotational speed of the transmission input shaft rises to a preset rotational speed point, and the acceleration rate of the transmission input shaft and the second clutch position are recorded to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque; further, the clutch friction point is determined according to the preset clutch torque-position curve and the second clutch position; further, the intermediate shaft braking torque is released, the clutch exhaust valve is controlled to be fully open and maintained for a first preset time, and the recorded third clutch position is the clutch engagement point. It can be seen that by introducing parameters such as the intermediate shaft braking torque, the deceleration resistance torque of the transmission input shaft rotating system, and the clutch transmission torque during the self-learning of the clutch characteristic points, the embodiments of the present invention can improve the learning accuracy of clutch characteristic points such as the clutch disengagement point, the clutch friction point, and the clutch engagement point, which is beneficial to alleviating problems such as slow vehicle start and poor smoothness caused by too high learning values of the friction point and the disengagement point. Description of the Drawings

[0037] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0038] Figure 1 is a flowchart of a method for self-learning clutch characteristic points provided by an embodiment of the present invention;

[0039] Figure 2 is a flowchart of another method for self-learning clutch characteristic points provided by an embodiment of the present invention;

[0040] Figure 3 It is a structural diagram of a clutch feature point self - learning device provided by an embodiment of the present invention;

[0041] Figure 4 It is a schematic structural diagram of an electronic device provided by an embodiment of the present invention;

[0042] Figure 5 It is a schematic curve diagram of a clutch feature point self - learning process provided by an embodiment of the present invention. Specific embodiments

[0043] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of them. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present application.

[0044] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "the" and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. "Plural" generally includes at least two.

[0045] It should be understood that the term "and / or" used herein is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0046] It should be understood that although terms such as first, second, and third may be used in the embodiments of the present application for description, these descriptions should not be limited to these terms. These terms are only used to distinguish the descriptions. For example, without departing from the scope of the embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

[0047] Depending on the context, the words "if", "when" as used herein may be interpreted as "when...", "while...", "in response to determining", or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detecting (stated condition or event)" may be interpreted as "when determined", "in response to determining", "when detecting (stated condition or event)", or "in response to detecting (stated condition or event)".

[0048] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a commodity or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such commodity or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the commodity or device comprising said element.

[0049] It should be particularly noted that symbols and / or numbers present in the specification that are not marked in the accompanying drawing description are not reference numerals.

[0050] Figure 1 FIG. is a flowchart of a method for self-learning clutch characteristic points provided by an embodiment of the present invention. This embodiment is applicable to the design scenario of self-learning control strategies for various clutches in various vehicles. For example, for the clutch of an electronically controlled mechanical automatic transmission (AMT) in a commercial vehicle, the method for self-learning clutch characteristic points can be, but is not limited to, executed by the self-learning device for clutch characteristic points in the embodiment of the present invention, and the execution entity can be implemented in software and / or hardware. Figure 5 FIG. is a schematic curve diagram of a self-learning process of clutch characteristic points provided by an embodiment of the present invention, as Figure 1 and Figure 5 shown, the method for self-learning clutch characteristic points at least includes the following steps:

[0051] S1. When the vehicle is in a preset state, in response to a preset operation, a self-learning command is triggered. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of clutch characteristic points is started.

[0052] Among them, the aforementioned step S1 mainly involves the triggering of self-learning of clutch characteristic points and the judgment of start conditions.

[0053] In a specific implementation manner, optionally, the vehicle being in a preset state at least means that the transmission of the vehicle is in neutral, the clutch is in the engaged position (i.e.), the engine is idling, and the rotational speed of the input shaft of the transmission is equal to the engine idle speed; the preset operation at least means the operation of the driver shifting from the forward gear (i.e., D gear) to neutral (i.e., N gear); the self-learning conditions at least include one of the air source pressure being within a first preset range, the engine speed being within a second preset range, the transmission oil temperature being within a third preset range, the clutch temperature being within a fourth preset range, and the output shaft speed being within a fifth preset range.

[0054] Among them, generally, when the vehicle is stationary, a self-learning command is triggered through a specific combination operation of the shift lever (such as shifting from D gear to N gear). Further, it is necessary to determine whether the relevant parameters of the vehicle's internal components meet the self-learning conditions, such as whether the air source pressure is within the range of 4 bar to 9 bar (i.e., the aforementioned first preset range), whether the engine speed is within the range of 400 rpm to 1000 rpm (i.e., the aforementioned second preset range), whether the transmission oil temperature is within the range of -40 °C to 120 °C (i.e., the aforementioned third preset range), whether the clutch temperature is within the range of -40 °C to 120 °C (i.e., the aforementioned fourth preset range), and / or whether the output shaft speed is within the range of 0 rpm to 20 rpm (i.e., the aforementioned fifth preset range), etc. If satisfied, the transmission starts to run the clutch self-learning program.

[0055] S2. Control the clutch to disengage at a preset speed. When the clutch disengages to the preset disengagement position, turn on the countershaft brake to keep the countershaft braking torque at the preset torque.

[0056] Among them, the preset speed can be 1 mm / s, and the preset torque can be 5 Nm (Newton meters).

[0057] In another specific embodiment, the aforementioned step S2 can be specifically: control the clutch to disengage at a speed of 1 mm / s. When the clutch disengages to a position at a length of L1 (for example, L1 can be 1 mm) from the preset disengagement point (when the method of this embodiment is executed for the first time, the preset disengagement point can be configured according to experience, such as the factory test data of the clutch; when the method of this embodiment is not executed for the first time, the preset disengagement point can be the clutch disengagement point obtained during the previous execution of the method) (this position is the preset disengagement position; assuming the preset disengagement point is 9 mm, then at this time the clutch disengages to 8 mm), turn on the intake valve of the countershaft brake for 5 ms and close the exhaust valve for 5 ms (here 5 ms is determined according to the hardware characteristics accumulated from the sample off-line test). Then, close the intake valve and keep the exhaust valve closed to make the countershaft braking torque be the preset T1 (such as T1 = 5 Nm) and keep T1 unchanged.

[0058] It can be understood that the execution entity of step S2 can be the Transmission Control Unit (TCU).

[0059] S3. Control the clutch to continue to disengage at a preset speed until the transmission input shaft speed drops by a preset speed difference, record the first clutch position, and obtain the clutch disengagement point according to the preset clutch torque-position curve and the first clutch position.

[0060] Among them, the preset speed difference can be, for example, 50 rpm.

[0061] In yet another specific embodiment, optionally, step S3 at least includes:

[0062] Controlling the clutch to continue to disengage at a preset speed until the rotational speed of the transmission input shaft drops by a preset rotational speed difference, recording the first clutch position at this time, and calculating the first position difference between when the clutch transmits zero torque and when it transmits a preset torque according to a preset clutch torque-position curve, so as to obtain the clutch disengagement point based on the first clutch position and the first position difference.

[0063] Among them, the clutch can continue to disengage at a speed of 1 mm / s until the rotational speed of the transmission input shaft drops by Dn1 (Dn1 is the preset rotational speed difference; for example, the rotational speed of the transmission input shaft drops from 700 rpm to 650 rpm), and record the clutch position P1 at this time (P1 is the first clutch position). Further, according to a preset clutch torque-position curve (optionally, the preset clutch torque-position curve is at least obtained by averaging the torque curves transmitted by a set number of clutches at different positions when the sample comes off the production line), using the linear interpolation method, calculate the position difference Poffset1 between when the clutch transmits 0 torque and when it transmits T1 torque (Poffset1 is the first position difference; for example, when the clutch position when transmitting 0 torque is 9 mm and the clutch position when transmitting 5 Nm torque is 8.2 mm, then the first position difference is 0.8 mm), and the clutch disengagement point Po = P1 + Poffset1 (if P1 = 7.8 mm, then Po = 8.6 mm; Po is also the position when the clutch transmits 0 torque).

[0064] S4. Controlling the clutch to continue to disengage at the maximum speed until the rotational speed of the transmission input shaft drops to a preset rotational speed point, recording the deceleration rate of the transmission input shaft at this time, and calculating the deceleration resistance torque of the input shaft rotating system according to the deceleration rate of the transmission input shaft and a preset moment of inertia.

[0065] Among them, the clutch disengaging at the maximum speed can correspond to the state where the clutch air intake valve is fully open; generally, the maximum speed of clutch disengagement is greater than 50 mm / s.

[0066] In yet another specific embodiment, quickly disengage the clutch at a speed of 55 mm / s until the rotational speed of the transmission input shaft drops to a preset rotational speed point n1 (such as n1 = 200 rpm). In the case of no other faults, at this time the clutch is fully disengaged. The judgment method can be that the clutch position at this time is more than 1 mm increased compared to the Po position, and record the deceleration rate Dw1 of the transmission input shaft at this time (such as Dw1 = 400 rpm / s = 41.8 rad / s). Further, according to the preset moment of inertia Jro of the input shaft rotating system when the transmission is in neutral (that is, the aforementioned preset moment of inertia; such as Jro = 0.2 kg·m 2), calculate the deceleration resistance torque TB of the input shaft rotation system = Jro * Dw1 (i.e., TB = 0.2 * 41.8 = 8.36 Nm).

[0067] S5. After the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to work at a preset torque and engage the clutch at a preset speed until the rotational speed of the transmission input shaft rises to the preset speed point, and record the rotational speed increase rate of the transmission input shaft and the position of the second clutch, so as to calculate the clutch transmission torque based on the preset moment of inertia, the rotational speed increase rate of the transmission input shaft, and the deceleration resistance torque.

[0068] Among them, controlling the intermediate shaft brake to work at a preset torque can be achieved by keeping the valve command of the intermediate shaft brake unchanged through the TCU.

[0069] In another specific embodiment, optionally, after the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to work at a preset torque and engage the clutch at a preset speed until the rotational speed of the transmission input shaft rises to the preset speed point, and record the rotational speed increase rate of the transmission input shaft and the position of the second clutch, so as to calculate the speed-up torque of the input shaft rotation system based on the preset moment of inertia and the rotational speed increase rate of the transmission input shaft, and then calculate the clutch transmission torque according to the speed-up torque and the deceleration resistance torque.

[0070] Among them, after the rotational speed of the transmission input shaft drops to 0 rpm, keep the intermediate shaft brake working at the braking torque T1 unchanged, control the clutch to engage at a preset speed such as 1 mm / s until the rotational speed of the transmission input shaft rises to the preset speed point n1, record the rotational speed increase rate Dw2 of the transmission input shaft at this time (such as Dw1 = 300 rpm / s = 31.4 rad / s), the position P2 of the second clutch (such as P2 = 6.6 mm), and then calculate the speed-up torque Tj of the input shaft rotation system = Jro * Dw2 (i.e., Tj = 0.2 * 31.4 = 6.28 Nm), and further calculate the clutch transmission torque Tc = TB + Tj (i.e., Tc = 8.36 + 6.28 = 14.64 Nm).

[0071] S6. Determine the clutch friction point according to the preset clutch torque-position curve and the position of the second clutch.

[0072] Among them, in another specific embodiment, optionally, step S6 at least includes:

[0073] Calculate the difference in the second position when the preset friction point torque is transmitted by the clutch and when the clutch transmission torque is transmitted according to the preset clutch torque-position curve, so as to determine the clutch friction point based on the difference in the second position and the position of the second clutch.

[0074] Specifically, according to the preset clutch torque-position curve and using the linear interpolation method, the position difference Poffset2 between the position for the clutch to transmit the preset friction point torque Tfr (the preset friction point torque can be obtained through pre-experiments, for example, Tfr = 20 Nm) and the position for transmitting the Tc torque can be calculated (Poffset2 is the second position difference; for example, if the position for transmitting 20 Nm torque is 5.8 mm and the position for transmitting 14.64 Nm torque is 6.2 mm, then the second position difference is -0.4 mm). Further, the clutch friction point Pfr = P2 + Poffset2 (Pfr = 6.5 - 0.4 = 6.1 mm).

[0075] S7. Release the braking torque of the intermediate shaft, control the clutch exhaust valve to be fully open and keep it for the first preset time, and record the third clutch position, which is the clutch engagement point.

[0076] Among them, step S7 can be at least:

[0077] After learning the new KP point, immediately release the braking torque of the intermediate shaft brake. (Wait until the clutch engages near the engagement point position, at this time the input shaft speed is equal to the idle speed), that is, open the exhaust valve to exhaust the intermediate shaft brake. Control the clutch exhaust valve to be fully open and keep it for the first preset time Tm1 (such as Tm1 = 2 s), and record the absolute position P3 of the clutch at this time (such as P3 = 20 mm), which is the clutch engagement point.

[0078] In the technical solution provided in this embodiment, first, when the vehicle is in a preset state, in response to a preset operation, a self-learning command is triggered. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of the clutch characteristic points starts. Further, the clutch is controlled to disengage at a preset speed. When the clutch disengages to a preset disengagement position, the intermediate shaft brake is turned on to keep the intermediate shaft braking torque at a preset torque. Further, the clutch is controlled to continue to disengage at a preset speed until the rotational speed of the transmission input shaft drops by a preset speed difference, and then the first clutch position is recorded. According to the preset clutch torque-position curve and the first clutch position, the clutch disengagement point is obtained. Further, the clutch is controlled to continue to disengage at the maximum speed until the rotational speed of the transmission input shaft drops to a preset rotational speed point, and then the deceleration rate of the transmission input shaft is recorded. According to the deceleration rate of the transmission input shaft and the preset moment of inertia, the deceleration resistance torque of the input shaft rotating system is calculated. Further, after the rotational speed of the transmission input shaft drops to zero, the intermediate shaft brake is controlled to operate at a preset torque and the clutch is controlled to engage at a preset speed until the rotational speed of the transmission input shaft rises to a preset rotational speed point, and then the acceleration rate of the transmission input shaft and the second clutch position are recorded to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque. Further, according to the preset clutch torque-position curve and the second clutch position, the clutch friction point is determined. Further, the intermediate shaft braking torque is released, the clutch exhaust valve is controlled to be fully open and maintained for a first preset time, and the recorded third clutch position is the clutch engagement point. Thus, in this embodiment, by introducing parameters such as the intermediate shaft braking torque, the deceleration resistance torque of the transmission input shaft rotating system, and the clutch transmission torque during the self-learning of the clutch characteristic points, the learning accuracy of the clutch characteristic points such as the clutch disengagement point, the clutch friction point, and the clutch engagement point can be improved, which is beneficial to alleviating problems such as slow vehicle start and poor smoothness caused by too high learning values of the friction point and the disengagement point.

[0079] Based on the above embodiments or implementation manners, the inventor also carefully studied and found that in the existing self-learning of clutch characteristic points, the learning frequency of the engagement point is low. As the temperature rises, it will not only cause untimely updates, but also cause problems such as starting jerk or inaccurate calculation of the clutch thermal model. In view of this, another method for self-learning clutch characteristic points is provided below; Figure 2 is a flowchart of another method for self-learning clutch characteristic points provided by an embodiment of the present invention, as Figure 2 and Figure 5 shown. This method for self-learning clutch characteristic points at least includes the following steps:

[0080] S1. When the vehicle is in a preset state, in response to a preset operation, a self-learning command is triggered. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of the clutch characteristic points starts.

[0081] S2. Control the clutch to disengage at a preset speed. When the clutch disengages to the preset disengagement position, activate the countershaft brake so that the countershaft braking torque remains at the preset torque.

[0082] S3. Control the clutch to continue disengaging at a preset speed until the transmission input shaft speed drops by a preset speed difference, then record the first clutch position, and obtain the clutch disengagement point based on the preset clutch torque-position curve and the first clutch position.

[0083] S4. Control the clutch to continue disengaging at the maximum speed until the transmission input shaft speed drops to the preset speed point, then record the deceleration rate of the transmission input shaft, and calculate the deceleration resistance torque of the input shaft rotating system based on the deceleration rate of the transmission input shaft and the preset moment of inertia.

[0084] S5. After the transmission input shaft speed drops to zero, control the countershaft brake to operate at the preset torque and make the clutch engage at a preset speed until the transmission input shaft speed rises to the preset speed point, then record the acceleration rate of the transmission input shaft and the second clutch position, so as to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft and the deceleration resistance torque.

[0085] S6. Determine the clutch friction point based on the preset clutch torque-position curve and the second clutch position.

[0086] S7. Release the countershaft braking torque, control the clutch exhaust valve to be fully open and last for the first preset time, and record the third clutch position, which is the clutch engagement point.

[0087] S8. When the vehicle is in gear and the clutch is fully engaged during driving, control the clutch exhaust valve to be fully open once every second preset time, and keep the clutch exhaust valve fully open within the first preset time. Also record the clutch position at this time as the third clutch position, which is also the clutch engagement point.

[0088] Wherein, the second preset time can be, for example, 60s.

[0089] It can be seen that, on the one hand, in this embodiment, by introducing parameters such as the intermediate shaft braking torque, the deceleration resistance torque of the transmission input shaft rotation system, and the clutch transmission torque during the self-learning process of the clutch characteristic points, the learning accuracy of the self-learning of the clutch characteristic points such as the clutch separation point, the clutch friction point, and the clutch engagement point can be improved, which is beneficial to alleviating problems such as slow vehicle start and poor smoothness caused by too high learning values of the friction point and the separation point. On the other hand, in this embodiment, when certain conditions are met (that is, the vehicle driving condition is in gear and the clutch is fully engaged), the engagement point learning frequency is increased. This not only can alleviate the drawback of the untimely update of the existing clutch characteristic point self-learning method, but also helps to solve problems such as starting jerk or inaccurate calculation of the clutch thermal model, which is beneficial to ensuring the accurate and real-time update of the clutch characteristic points.

[0090] It should be noted that, in another specific embodiment, T1 can be equal to the preset friction point torque Tfr minus the average value Ts of the transmission system resistance torque; the aforementioned average value of the transmission system resistance torque can be obtained by testing the deceleration rate of the first preset number of samples when the sample comes off the production line, and then calculating the resistance torque according to the product of the moment of inertia Jro of the input shaft rotation system and the deceleration rate, and taking the average value to determine.

[0091] It should also be noted that, in another specific embodiment, when the sample comes off the production line, the braking torque of the second preset number of samples at different valve opening times can be tested, and then according to the linear fitting result of the valve opening time and the braking torque, the valve opening time control parameter corresponding to the transmission of the T1 braking torque can be determined.

[0092] It still should be noted that, in another specific embodiment, the moment of inertia of all rotating parts connected to the input shaft can be equivalently calculated to the position of the input shaft, and the sum of all equivalent moments of inertia is the moment of inertia Jro of the input shaft rotation system.

[0093] Figure 3 It is the structural diagram of a clutch characteristic point self-learning device provided by an embodiment of the present invention. This embodiment is applicable to the design scenarios of self-learning control strategies for various clutches in various vehicles. For example, for the AMT clutch in commercial vehicles, this clutch characteristic point self-learning device can be implemented in software and / or hardware. As Figure 3 shown, this clutch characteristic point self-learning device at least includes:

[0094] A self-learning trigger module, configured to, when the vehicle is in a preset state, respond to a preset operation to trigger a self-learning command, and if it is further determined that the vehicle meets the self-learning conditions, start the self-learning of the clutch characteristic points;

[0095] The first control module is used to control the clutch to disengage at a preset speed. When the clutch disengages to a preset disengagement position, the intermediate shaft brake is activated to keep the intermediate shaft braking torque at a preset torque.

[0096] The second control module is used to control the clutch to continue to disengage at a preset speed until the rotational speed of the transmission input shaft drops by a preset speed difference, at which point the first clutch position is recorded, and the clutch disengagement point is obtained based on the preset clutch torque-position curve and the first clutch position.

[0097] The third control module is used to control the clutch to continue to disengage at the maximum speed until the rotational speed of the transmission input shaft drops to a preset rotational speed point, at which point the deceleration rate of the transmission input shaft is recorded, and the deceleration resistance torque of the input shaft rotating system is calculated based on the deceleration rate of the transmission input shaft and the preset moment of inertia.

[0098] The fourth control module is used to, after the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to operate at a preset torque and make the clutch engage at a preset speed until the rotational speed of the transmission input shaft rises to a preset rotational speed point, at which point the acceleration rate of the transmission input shaft and the second clutch position are recorded, so as to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque.

[0099] The friction point determination module is used to determine the clutch friction point based on the preset clutch torque-position curve and the second clutch position.

[0100] The fifth control module is used to release the intermediate shaft braking torque, control the clutch exhaust valve to be fully open and maintain it for a first preset time, and record the third clutch position as the clutch engagement point.

[0101] Optionally, it further includes:

[0102] The sixth control module is used to, when the vehicle driving condition is in gear and the clutch is fully engaged, control the clutch exhaust valve to be fully open once every second preset time, and keep the clutch exhaust valve fully open within the first preset time, and also record the clutch position at this time as the third clutch position, which is also the clutch engagement point.

[0103] Optionally, the vehicle being in a preset state at least means that the vehicle's transmission is in neutral, the clutch is in the engaged position, the engine is idling, and the rotational speed of the transmission input shaft is equal to the engine idle speed.

[0104] The preset operation at least means the operation of the driver shifting from the forward gear to the neutral gear.

[0105] The self-learning conditions include at least one of the following: the air source pressure is within a first preset range, the engine speed is within a second preset range, the transmission oil temperature is within a third preset range, the clutch temperature is within a fourth preset range, and the output shaft speed is within a fifth preset range.

[0106] Optionally, the second control module is at least specifically configured to:

[0107] Control the clutch to continue to disengage at a preset speed until the transmission input shaft speed drops by a preset speed difference, record the first clutch position, and calculate the first position difference between when the clutch transmits zero torque and when it transmits a preset torque according to the preset clutch torque-position curve, so as to obtain the clutch disengagement point based on the first clutch position and the first position difference.

[0108] Optionally, the fourth control module is at least specifically configured to:

[0109] After the transmission input shaft speed drops to zero, control the countershaft brake to operate at a preset torque and make the clutch engage at a preset speed until the transmission input shaft speed rises to a preset speed point, record the transmission input shaft speed increase rate and the second clutch position, calculate the speed increase torque of the input shaft rotation system based on the preset moment of inertia and the transmission input shaft speed increase rate, and then calculate the clutch transmission torque according to the speed increase torque and the speed decrease resistance torque.

[0110] Optionally, the friction point determination module is at least specifically configured to:

[0111] Calculate the second position difference between when the clutch transmits the preset friction point torque and when it transmits the clutch transmission torque according to the preset clutch torque-position curve, so as to determine the clutch friction point based on the second position difference and the second clutch position.

[0112] Optionally, the preset clutch torque-position curve is obtained by, at least when the sample comes off the production line, taking the average value of the torque curves transmitted by a set number of clutches at different positions through testing.

[0113] For the technical solution provided in this embodiment, first, when the vehicle is in a preset state, the self-learning trigger module responds to a preset operation to trigger a self-learning command. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of the clutch characteristic points starts; further, the first control module controls the clutch to disengage at a preset speed. When the clutch disengages to a preset disengagement position, the intermediate shaft brake is turned on to keep the intermediate shaft braking torque at a preset torque; further, the second control module controls the clutch to continue to disengage at a preset speed until the transmission input shaft speed drops by a preset speed difference, and then records the first clutch position. The clutch disengagement point is obtained based on the preset clutch torque-position curve and the first clutch position; further, the third control module controls the clutch to continue to disengage at the maximum speed until the transmission input shaft speed drops to a preset speed point, and then records the deceleration rate of the transmission input shaft. The deceleration resistance torque of the input shaft rotation system is calculated based on the deceleration rate of the transmission input shaft and the preset moment of inertia; further, after the transmission input shaft speed drops to zero, the fourth control module controls the intermediate shaft brake to work at a preset torque and makes the clutch engage at a preset speed until the transmission input shaft speed rises to a preset speed point, and then records the acceleration rate of the transmission input shaft and the second clutch position to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque; further, the friction point determination module determines the clutch friction point based on the preset clutch torque-position curve and the second clutch position; further, the fifth control module releases the intermediate shaft braking torque, controls the clutch exhaust valve to be fully open and lasts for a first preset time, and records the third clutch position as the clutch engagement point. It can be seen that in this embodiment, by introducing parameters such as the intermediate shaft braking torque, the deceleration resistance torque of the transmission input shaft rotation system, and the clutch transmission torque during the self-learning of the clutch characteristic points, the learning accuracy of the clutch characteristic points such as the clutch disengagement point, the clutch friction point, and the clutch engagement point can be improved, which is beneficial to alleviating problems such as slow vehicle start and poor smoothness caused by too high learning values of the friction point and the disengagement point.

[0114] The embodiment of the present invention also provides an electronic device. Figure 4 It is a schematic structural diagram of an electronic device provided by the embodiment of the present invention. Refer to Figure 4, the electronic device 1000 includes a processor 1001 and a memory 1002. The memory 1002 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 1001, the steps in any one of the above clutch characteristic point self-learning methods are run. Through the above technical solution, the processor 1001 and the memory 1002 are interconnected and communicate with each other through a communication bus and / or other forms of connection mechanisms (not shown). The memory 1002 stores a computer program executable by the processor. When the electronic device 1000 runs, the processor 1001 executes the computer program to perform the clutch characteristic point self-learning method in any optional implementation manner of the above embodiments, so as to at least achieve the following functions: when the vehicle is in a preset state, in response to a preset operation, trigger a self-learning command. If it is further determined that the vehicle meets the self-learning conditions, start the clutch characteristic point self-learning; control the clutch to disengage at a preset speed. When the clutch disengages to a preset disengagement position, turn on the countershaft brake so that the countershaft braking torque remains at a preset torque; control the clutch to continue to disengage at a preset speed until the transmission input shaft speed drops by a preset speed difference, record the first clutch position, and obtain the clutch disengagement point according to the preset clutch torque-position curve and the first clutch position; control the clutch to continue to disengage at the maximum speed until the transmission input shaft speed drops to a preset speed point, record the deceleration rate of the transmission input shaft, and calculate the deceleration resistance torque of the input shaft rotation system according to the deceleration rate of the transmission input shaft and the preset moment of inertia; after the transmission input shaft speed drops to zero, control the countershaft brake to work at a preset torque and make the clutch engage at a preset speed until the transmission input shaft speed rises to a preset speed point, record the acceleration rate of the transmission input shaft and the second clutch position, so as to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque; determine the clutch friction point according to the preset clutch torque-position curve and the second clutch position; release the countershaft braking torque, control the clutch exhaust valve to be fully open and last for a first preset time, and record the third clutch position as the clutch engagement point.

[0115] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the clutch characteristic point self-learning method provided by all the inventive embodiments of the present application: when the vehicle is in a preset state, in response to a preset operation, a self-learning command is triggered. If it is further determined that the vehicle meets the self-learning conditions, the self-learning of the clutch characteristic points is started; the clutch is controlled to disengage at a preset speed. When the clutch disengages to a preset disengagement position, the intermediate shaft brake is turned on to keep the intermediate shaft braking torque at a preset torque; the clutch is controlled to continue to disengage at a preset speed until the transmission input shaft speed drops by a preset speed difference, and the first clutch position is recorded. The clutch disengagement point is obtained according to the preset clutch torque-position curve and the first clutch position; the clutch is controlled to continue to disengage at the maximum speed until the transmission input shaft speed drops to a preset speed point, and the deceleration rate of the transmission input shaft is recorded. The deceleration resistance torque of the input shaft rotating system is calculated according to the deceleration rate of the transmission input shaft and the preset moment of inertia; after the transmission input shaft speed drops to zero, the intermediate shaft brake is controlled to work at a preset torque and the clutch is controlled to engage at a preset speed until the transmission input shaft speed rises to a preset speed point, and the acceleration rate of the transmission input shaft and the second clutch position are recorded to calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft and the deceleration resistance torque; the clutch friction point is determined according to the preset clutch torque-position curve and the second clutch position; the intermediate shaft braking torque is released, the clutch exhaust valve is controlled to be fully open and maintained for a first preset time, and the third clutch position recorded is the clutch engagement point.

[0116] One or more computer-readable media in any combination can be adopted. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples (non-exhaustive list) of the computer-readable storage medium include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an EPROM, or a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, the computer-readable storage medium can be any tangible medium that contains or stores a program, and the program can be used by or in combination with an instruction execution system, apparatus, or device.

[0117] A computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, in which computer-readable program code is carried. Such a propagated data signal may take many forms, including - but not limited to - an electromagnetic signal, an optical signal, or any suitable combination of the foregoing. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device.

[0118] The program code contained on a computer-readable medium may be transmitted using any appropriate medium, including - but not limited to - wireless, wire, optical fiber cable, RF, and the like, or any suitable combination of the foregoing.

[0119] The computer program code for performing the operations of the present invention may be written in one or more programming languages or combinations thereof. The programming languages include object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, executed as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., by using an Internet service provider to connect through the Internet).

[0120] The above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A self - learning method for clutch characteristic points, characterized in that At least include the following steps: S1. When the vehicle is in a preset state, in response to a preset operation, trigger a self-learning command. If it is further determined that the vehicle meets the self-learning conditions, start the self-learning of the clutch characteristic points; S2. Control the clutch to disengage at a preset speed. When the clutch disengages to a preset disengagement position, turn on the intermediate shaft brake to keep the intermediate shaft braking torque at a preset torque; S3. Control the clutch to continue to disengage at the preset speed until the transmission input shaft speed drops by a preset speed difference, record the first clutch position, and obtain the clutch disengagement point according to the preset clutch torque-position curve and the first clutch position; S4. Control the clutch to continue to disengage at the maximum speed until the transmission input shaft speed drops to a preset speed point, record the deceleration rate of the transmission input shaft, and calculate the deceleration resistance torque of the input shaft rotating system according to the deceleration rate of the transmission input shaft and the preset moment of inertia; S5. After the transmission input shaft speed drops to zero, control the intermediate shaft brake to work at the preset torque and make the clutch engage at the preset speed until the transmission input shaft speed rises to the preset speed point, record the acceleration rate of the transmission input shaft and the second clutch position, and calculate the clutch transmission torque based on the preset moment of inertia, the acceleration rate of the transmission input shaft, and the deceleration resistance torque; S6. Determine the clutch friction point according to the preset clutch torque-position curve and the second clutch position; S7. Release the intermediate shaft braking torque, control the clutch exhaust valve to be fully open and last for a first preset time, and record the third clutch position as the clutch engagement point.

2. The self-learning method for the characteristic points of the clutch according to claim 1, wherein It also includes: S8. When the vehicle driving condition is in gear and the clutch is fully engaged, control the clutch exhaust valve to be fully open once every second preset time, and keep the clutch exhaust valve fully open within the first preset time. Similarly, record the clutch position at this time as the third clutch position, which is also the clutch engagement point.

3. The clutch characteristic point self-learning method according to claim 1, characterized in that The vehicle being in the preset state at least means that the vehicle's transmission is in neutral, the clutch is in the engaged position, the engine is idling, and the transmission input shaft speed is equal to the engine idle speed; The preset operation at least means the operation of the driver shifting from the forward gear to the neutral gear; The self-learning conditions at least include one of the air source pressure being in a first preset range, the engine speed being in a second preset range, the transmission oil temperature being in a third preset range, the clutch temperature being in a fourth preset range, and the output shaft speed being in a fifth preset range.

4. The self - learning method for the characteristic points of the clutch according to claim 1, wherein Step S3 at least includes: Control the clutch to continue to disengage at the preset speed until the transmission input shaft speed drops by the preset speed difference, record the first clutch position, and calculate the first position difference when the clutch transmits zero torque and the preset torque according to the preset clutch torque-position curve, so as to obtain the clutch disengagement point based on the first clutch position and the first position difference.

5. The self-learning method for the characteristic points of the clutch according to claim 1, characterized in that Step S5 at least includes: After the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to operate at the preset torque and engage the clutch at the preset speed until the rotational speed of the transmission input shaft rises to the preset speed point, and record the rotational speed increase rate of the transmission input shaft and the position of the second clutch, so as to calculate the speed increase torque of the input shaft rotating system based on the preset moment of inertia and the rotational speed increase rate of the transmission input shaft, and further calculate the clutch transmission torque according to the speed increase torque and the speed decrease resistance torque.

6. The self-learning method for clutch characteristic points according to claim 1, characterized in that Step S6 at least includes: Calculate the second position difference when the clutch transmits the preset friction point torque and when it transmits the clutch transmission torque according to the preset clutch torque-position curve, so as to determine the clutch friction point based on the second position difference and the position of the second clutch.

7. The self - learning method for the characteristic points of the clutch according to claim 1, wherein The preset clutch torque-position curve is obtained at least by taking the average value of the torque curves transmitted by a set number of clutches at different positions when the sample comes off the production line.

8. A self-learning device for clutch characteristic points, characterized in that, At least includes: A self-learning trigger module, configured to, when the vehicle is in a preset state, trigger a self-learning command in response to a preset operation, and if it is further determined that the vehicle meets the self-learning conditions, start the self-learning of the clutch characteristic points; A first control module, configured to control the clutch to disengage at a preset speed, and when the clutch disengages to a preset disengagement position, turn on the intermediate shaft brake so that the intermediate shaft braking torque remains at the preset torque; A second control module, configured to control the clutch to continue to disengage at the preset speed until the rotational speed of the transmission input shaft drops by a preset speed difference, record the position of the first clutch, and obtain the clutch disengagement point according to the preset clutch torque-position curve and the position of the first clutch; A third control module, configured to control the clutch to continue to disengage at the maximum speed until the rotational speed of the transmission input shaft drops to a preset speed point, record the rotational speed decrease rate of the transmission input shaft, and calculate the speed decrease resistance torque of the input shaft rotating system according to the rotational speed decrease rate of the transmission input shaft and the preset moment of inertia; A fourth control module, configured to, after the rotational speed of the transmission input shaft drops to zero, control the intermediate shaft brake to operate at the preset torque and engage the clutch at the preset speed until the rotational speed of the transmission input shaft rises to the preset speed point, record the rotational speed increase rate of the transmission input shaft and the position of the second clutch, so as to calculate the clutch transmission torque based on the preset moment of inertia, the rotational speed increase rate of the transmission input shaft, and the speed decrease resistance torque; A friction point determination module, configured to determine the clutch friction point according to the preset clutch torque-position curve and the position of the second clutch; A fifth control module, configured to release the intermediate shaft braking torque, control the clutch exhaust valve to be fully open and last for a first preset time, and record the position of the third clutch as the clutch engagement point.

9. An electronic device, characterized in that, It includes a processor and a memory, and the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps in the clutch characteristic point self-learning method according to any one of claims 1-7 are run.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by a processor, it implements the self-learning method for the characteristic points of the clutch according to any one of claims 1-7.

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