Gearbox gear self-learning method and device, vehicle and storage medium

Abstract

The invention provides a gearbox gear self-learning method and device, a vehicle and a storage medium, the method is applied to the field of motor control, and the method comprises the steps that when a gearbox of the vehicle is in a gear self-learning process, whether a combination gear and a combination sleeve are in a top tooth state or not under a current gear is determined; under the condition that the combination teeth and the combination sleeve are in the tooth abutting state, the gear shifting motor is controlled to enter a torque control mode; and in the torque control mode, the gear shifting motor is controlled to operate based on a plurality of dislocation requests so as to eliminate the top tooth state, and the rotation speed direction of the dislocation requests is opposite to the torque direction. According to the method, in the gear self-learning process of the gearbox, if the combination teeth and the combination sleeve are in the tooth abutting state, the gear shifting motor is controlled to enable the combination sleeve and the combination teeth to smoothly exit from the tooth abutting state, excessive abrasion of the gear shifting fork is avoided, and the accuracy of gear shifting self-learning is improved.

Description

Technical Field

[0001] This application relates to the field of motor control, and more specifically, to a method, apparatus, vehicle, and storage medium for self-learning of gearbox gear positions in the field of motor control. Background Technology

[0002] With the development of vehicle manufacturing technology, Automated Mechanical Transmission (AMT) has gradually replaced traditional manual and automatic transmissions and is being used in vehicles. AMT transmissions are based on the structure of manual transmissions, but with the addition of clutch and shift mechanisms.

[0003] For vehicles equipped with AMT (Automated Manual Transmission), automatic gear shifting is mainly achieved through the Electronic Control Unit (ECU) and actuators. Specifically, during the gear shifting process, the ECU controls the clutch actuator to disengage the clutch and controls the shift actuator (usually a shift motor) to start. The rotation of the shift motor causes the shift fork to move to the target position, thereby completing the gear shift.

[0004] To ensure that the shift fork can move accurately to the target position during gear shifting, it is generally necessary to control the vehicle to perform gear self-learning before driving.

[0005] In one possible implementation, if the engagement sleeve and engagement teeth are in the top tooth state during the gearbox gear self-learning process, the shift fork will be subjected to a large impact force, causing wear on the shift fork and easily leading to inaccurate shifting.

[0006] Therefore, during the gearbox gear self-learning process, when the engagement sleeve and engagement teeth are in the top tooth state, how to minimize the wear of the shift fork has become an urgent problem to be solved. Summary of the Invention

[0007] This application provides a method, apparatus, vehicle, and storage medium for gearbox gear self-learning. The method enables the gearbox gear self-learning process to smoothly disengage the gear and engagement sleeve from the top tooth state by controlling the shift motor, if the engagement teeth and engagement sleeve are in the top tooth state, thereby avoiding excessive wear of the shift fork and improving the accuracy of gear shift self-learning.

[0008] Firstly, a method for gearbox gear self-learning is provided. The method includes: during the gearbox self-learning process of a vehicle, determining whether the engagement teeth and engagement sleeve are in a tooth-over-tooth state in the current gear; when the engagement teeth and engagement sleeve are in a tooth-over-tooth state, controlling the shift motor to enter a torque control mode; in the torque control mode, controlling the shift motor to operate based on multiple misalignment requests to eliminate the tooth-over-tooth state, wherein the misalignment request is a request in which the rotational speed direction is opposite to the torque direction.

[0009] In the above technical solution, during the gearbox self-learning process, if the engagement teeth and engagement sleeve experience tooth overlap, the vehicle can control the shift motor to enter torque control mode. In torque control mode, the vehicle can control the shift motor to operate based on multiple misalignment requests. These misalignment requests are requests where the shift motor's rotational speed is opposite to the torque direction. For the shift motor, when the rotational speed is opposite to the torque direction, the torque generated during rotation is opposite to the direction of motion. This reverse torque causes the engagement sleeve to move slightly from the tooth overlap position, thereby loosening the stuck engagement teeth and engagement sleeve. Repeating this process multiple times allows the engagement sleeve and engagement teeth to exit the tooth overlap state, ensuring the engagement sleeve can smoothly enter the meshing position, avoiding prolonged wear of the shift fork and other mechanical components, and improving the accuracy of the shift fork's movement position. Accurate shifting positions improve shifting reliability, thereby increasing the success rate of the gearbox's gear position self-learning.

[0010] In conjunction with the first aspect, in some possible implementations, the method further includes: determining a first output torque corresponding to a first gear shifting stage, a second output torque corresponding to a second gear shifting stage, and a critical position of the first gear shifting stage and the second gear shifting stage, wherein the critical position is the position of the shift fork at the end of the first gear shifting stage; and controlling the transmission to perform self-learning based on the first output torque, the second output torque, and the critical position.

[0011] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the second output torque is determined by the following steps: controlling the gear shift motor to operate on a test bench based on multiple different duty cycles with unauthorized transmission until the shift fork is in the optimal limit position, recording the duty cycle corresponding to the optimal limit position as the first duty cycle, the optimal limit position being used to indicate that the engagement tooth and the engagement sleeve are fully engaged and the associated gear can rotate; controlling the gear shift motor to operate on the vehicle based on the first duty cycle, obtaining the torque of the gear shift motor under the first duty cycle and determining it as the second output torque.

[0012] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the critical position is determined by the following steps: determining the synchronization position during the vehicle's transmission history gear self-learning process, the synchronization position being obtained based on the position of the shift fork when the engagement tooth and the engagement sleeve are in the top tooth state; and determining the critical position based on the optimal limit position and the synchronization position.

[0013] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the first output torque is determined by the following steps: controlling the gear shift motor to operate based on a first duty cycle on the vehicle, and recording the position of the shift fork as the optimal theoretical position value; continuously controlling the transmission to perform self-learning on the vehicle based on the second output torque, the critical position, and multiple different third output torques corresponding to the first gear shift stage, until the absolute value of the first difference between the optimal position value obtained by the transmission after self-learning and the optimal theoretical position value is less than a first threshold, and determining the third output torque corresponding to the optimal position value whose absolute value of the first difference between the optimal theoretical position value and the optimal position value is less than the first threshold as the first output torque.

[0014] In the above technical solution, when determining the first output torque corresponding to the first gear shift stage, the vehicle has already determined the second output torque and critical position for the second gear shift stage. Therefore, in this application, the vehicle can keep the second output torque and critical position constant, thereby outputting different third output torques to control the shift motor, thus determining the optimal position value of the shift fork obtained after self-learning under different third output torques. Finally, the absolute value of the difference between the optimal position value and the optimal theoretical position value under each third output torque is compared with a threshold to determine if they are close. If they are relatively close, the corresponding third output torque is used as the first output torque. This process ensures precise control of the shift motor during gear shifting by controlling it with torque, ensuring that the shift fork can operate to the optimal position.

[0015] In conjunction with the first aspect and the above implementation methods, in some possible implementation methods, whether the engagement tooth and the engagement sleeve are in a tooth-tightening state is determined by the following steps: during the gearbox's gear self-learning process, the current position of the shift fork and the subsequent position change of the shift fork are obtained; if the current position is greater than a preset position and the duration of the position change being less than the preset change is greater than a preset duration, it is determined that the engagement tooth and the engagement sleeve are not in a tooth-tightening state; if the current position is less than or equal to the preset position, or the position change is greater than or equal to the preset change, or the duration of the position change being less than the preset change is less than or equal to the preset duration, it is determined that the engagement tooth and the engagement sleeve are in a tooth-tightening state.

[0016] In the above technical solution, during the shift self-learning process, this application also proposes a method to determine whether the engagement sleeve and engagement teeth are in the top tooth state. Specifically, the vehicle monitors the current position of the shift fork and the amount of position change of the shift fork in real time. When the current position of the shift fork is greater than a given preset position and the amount of position change tends to stabilize within a certain period of time, it indicates that the shift fork is in the gear position too deep and cannot move further, and the vehicle determines that the engagement sleeve and engagement teeth are in the top tooth state. The above process can promptly determine whether the engagement sleeve and engagement teeth are in the top tooth state during the shift self-learning process, avoiding mechanical component wear caused by the engagement sleeve and engagement teeth being in the top tooth state for a long time.

[0017] In conjunction with the first aspect and the above implementation methods, in some possible implementation methods, after the transmission is controlled to perform self-learning based on the first output torque, the second output torque, and the critical position, the method further includes: when the vehicle's mileage is equal to a first preset mileage, controlling the transmission to perform a first repeated self-learning based on the first output torque, the second output torque, and the critical position; determining the absolute value of a second difference between the first repeated self-learning and the two optimal position values ​​obtained from the previous self-learning; and continuing to control the transmission based on the first output torque, the second output torque, and the critical position when the absolute value of the second difference is less than a second threshold. The transmission operates as follows: if the absolute value of the second difference is greater than or equal to the second threshold, and if the mileage is equal to the second preset mileage, the transmission is controlled to perform a second round of self-learning based on the first output torque, the second output torque, and the critical position; the absolute value of the third difference between the two optimal position values ​​obtained from the second round of self-learning and the first round of self-learning is determined; if the absolute value of the third difference is less than the second threshold, the transmission continues to operate based on the first output torque, the second output torque, and the critical position; if the absolute value of the third difference is greater than or equal to the second threshold, the first output torque and the second output torque are updated.

[0018] In the above technical solution, when the self-learning mileage is long, to verify the stability of the self-learning results, the vehicle can also determine whether the difference between the two most recent optimal position values ​​is too large. If the difference is too large, it indicates that the current self-learning result is no longer stable, and the vehicle can promptly update the output torque of the shift motor to obtain a better shift motor control strategy. If the difference is small, it indicates that the current self-learning process is stabilizing, and the transmission can continue to be controlled to learn with the corresponding parameters. This process allows the output torque to be adjusted according to actual operating conditions during the transmission's self-learning process, improving the adaptability and reliability of the self-learning process.

[0019] Secondly, a transmission gear self-learning device is provided, comprising: a state determination module, used to determine whether the engagement teeth and engagement sleeve are in a top-tooth state under the current gear during the transmission gear self-learning process; a mode control module, used to control the shift motor to enter a torque control mode when the engagement teeth and engagement sleeve are in a top-tooth state; and an operation control module, used to control the shift motor to operate based on multiple misalignment requests in the torque control mode to eliminate the top-tooth state, wherein the misalignment request is a request in which the rotational speed direction is opposite to the torque direction.

[0020] In conjunction with the second aspect, in some possible implementations, the device further includes: a parameter determination module, used to determine the first output torque corresponding to the first gear shifting stage, the second output torque corresponding to the second gear shifting stage, and the critical position of the first gear shifting stage and the second gear shifting stage, the critical position being the position of the shift fork at the end of the first gear shifting stage; and to control the transmission to perform self-learning based on the first output torque, the second output torque, and the critical position.

[0021] In combination with the second aspect and the above implementation methods, in some possible implementation methods, the parameter determination module is specifically used to: control the gear shift motor to operate on a test bench based on multiple different duty cycles sent in an unauthorized manner until the shift fork is in the optimal limit position, record the duty cycle corresponding to the optimal limit position as the first duty cycle, the optimal limit position is used to indicate that the engagement tooth and the engagement sleeve are fully engaged and the associated gear can rotate; control the gear shift motor to operate on the vehicle based on the first duty cycle, obtain the torque of the gear shift motor under the first duty cycle and determine it as the second output torque.

[0022] In conjunction with the second aspect and the above implementation methods, in some possible implementation methods, the parameter determination module is also used to: determine the synchronization position during the vehicle's transmission history gear self-learning process, the synchronization position being obtained based on the position of the shift fork when the engagement tooth and the engagement sleeve are in the top tooth state; and determine the critical position based on the optimal limit position and the synchronization position.

[0023] In conjunction with the second aspect and the above implementation methods, in some possible implementation methods, the parameter determination module is further configured to: control the gear shift motor to operate on the vehicle based on a first duty cycle, and record the position of the shift fork as the optimal theoretical position value; continuously control the transmission to perform self-learning on the vehicle based on the second output torque, the critical position, and multiple different third output torques corresponding to the first gear shifting stage, until the absolute value of the first difference between the optimal position value obtained by the transmission after self-learning and the optimal theoretical position value is less than a first threshold, and determine the third output torque corresponding to the optimal position value whose absolute value of the first difference between the optimal theoretical position value and the optimal position value is less than the first threshold as the first output torque.

[0024] In conjunction with the second aspect and the above implementation methods, in some possible implementation methods, the state determination module is specifically used to: obtain the current position of the shift fork and the position change of the shift fork at subsequent times during the gear self-learning process of the transmission; determine that the engagement tooth and the engagement sleeve are not in the top tooth state when the current position is greater than a preset position and the duration of the position change being less than the preset change is greater than a preset duration; determine that the engagement tooth and the engagement sleeve are in the top tooth state when the current position is less than or equal to the preset position, or the position change is greater than or equal to the preset change, or the duration of the position change being less than the preset change is less than or equal to the preset duration.

[0025] In conjunction with the second aspect and the above implementation methods, in some possible implementation methods, after the transmission is controlled to perform self-learning based on the first output torque, the second output torque, and the critical position, the device further includes: a torque update module, used to control the transmission to perform a first repeated self-learning based on the first output torque, the second output torque, and the critical position when the vehicle's mileage is equal to a first preset mileage; determine the absolute value of a second difference between the first repeated self-learning and the two optimal position values ​​obtained from the previous self-learning; and continue to control the transmission based on the first output torque, the second output torque, and the critical position when the absolute value of the second difference is less than a second threshold. The transmission is controlled to operate; if the absolute value of the second difference is greater than or equal to the second threshold, and if the mileage is equal to the second preset mileage, the transmission is controlled to perform a second repeated self-learning based on the first output torque, the second output torque, and the critical position; the absolute value of the third difference between the two optimal position values ​​obtained from the second repeated self-learning and the first repeated self-learning is determined; if the absolute value of the third difference is less than the second threshold, the transmission is controlled to operate based on the first output torque, the second output torque, and the critical position; if the absolute value of the third difference is greater than or equal to the second threshold, the first output torque and the second output torque are updated.

[0026] Thirdly, a vehicle is provided, including a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, causing the vehicle to perform the methods described in the first aspect or any possible implementation thereof.

[0027] Fourthly, a computer program product is provided, comprising: computer program code, which, when run on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof.

[0028] Fifthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of an ATM gearbox provided in an embodiment of this application;

[0030] Figure 2 This is a schematic flowchart illustrating a method for self-learning gear positions in a transmission according to an embodiment of this application;

[0031] Figure 3 This is a schematic diagram of a scenario for determining a critical position provided in an embodiment of this application;

[0032] Figure 4 This is a schematic diagram illustrating a scenario where the gearbox fails to learn shifting when the shift motor does not employ zero-oscillation, as provided in an embodiment of this application.

[0033] Figure 5 This is a schematic diagram illustrating a scenario where the gearbox successfully learns to shift gears when the shift motor uses zero-crossing oscillation, according to an embodiment of this application.

[0034] Figure 6 This is a schematic diagram of the structure of a gearbox gear self-learning device provided in an embodiment of this application;

[0035] Figure 7 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application. Detailed Implementation

[0036] The technical solutions in this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.

[0037] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0038] Before introducing the solutions of the embodiments of this application, the terms that may be involved in the embodiments of this application will be explained first.

[0039] ATM transmission, also known as an automatic-manual transmission or semi-automatic transmission, is a type of manual transmission that automatically shifts gears through an electronic control system. It combines the high efficiency of a manual transmission with the convenience of an automatic transmission. The main components of an ATM transmission include gear sets, synchronizers, shift forks, sliding sleeves, clutches, an ECU, position sensors, speed sensors, actuators, and a shift controller. The transmissions mentioned in the embodiments of this application refer to ATM transmissions.

[0040] To facilitate understanding of the solutions in the embodiments of this application, the structure and working principle of the ATM gearbox will be introduced first.

[0041] Figure 1 This is a schematic diagram of the structure of an ATM gearbox provided in an embodiment of this application.

[0042] For example, such as Figure 1 As shown, the main components of the ATM transmission 100 include gear sets, synchronizers, sliding sleeves (also known as engagement sleeves), position sensors, clutches, shift controllers, speed sensors, actuators, shift forks, and ECUs.

[0043] In one possible implementation, the gear set includes an input shaft, an output shaft, an intermediate shaft, and gears. The synchronizer includes a synchronizing ring and a conical surface.

[0044] Based on the various components of the ATM gearbox described above, the working process of each component during vehicle gear shifting is as follows:

[0045] When a gear shift is required, the driver sends a shift request via the shift button, paddle shifters, or other control devices. The shift controller receives the current driver's shift request and sends it to the ECU.

[0046] The ECU receives a shift request and begins the shift process, sending a shift command to the actuator to disengage the clutch and cut off the power transmission between the engine and the transmission.

[0047] After the actuator drives the clutch to disengage, the ECU calculates the distance and direction the shift fork needs to move based on the current gear and the target gear. The ECU then controls the actuator (usually the shift motor) to drive the shift fork, moving it accordingly.

[0048] During the shift fork's movement, a position sensor monitors its position in real time and feeds the data back to the ECU, ensuring the shift fork moves to the correct position during gear shifting. The shift fork's movement pushes the sliding sleeve axially, selecting the target gear (i.e., the engaging gear) corresponding to the desired gear. A synchronizer ring is located between the sliding sleeve and the engaging gear, using friction to ensure the engaging gear and the spindle rotate at the same speed. Both the inner side of the synchronizer ring and the outer side of the engaging gear have tapered surfaces; friction is generated through the contact of these tapered surfaces.

[0049] When the engagement gear and the main shaft rotate at the same speed, the sliding sleeve engages with the engagement gear, completing gear selection and engagement. A speed sensor monitors the speeds of the main shaft and the engagement gear, ensuring they rotate at the same speed when in a synchronized position. The ECU receives data from the speed sensor and determines whether synchronization has been achieved. When the sliding sleeve and engagement gear are fully engaged and rotating at the same speed, the ECU sends a command to the actuator to re-engage the clutch. The actuator drives the clutch to engage, restoring power transmission between the engine and the transmission. The gear shift is complete.

[0050] The ECU confirms the shift process is complete and updates the current gear. The position sensor continues to monitor the position of the shift fork and slide sleeve to ensure they remain in the correct positions. The speed sensor continues to monitor the rotational speed of the spindle and engagement gears to ensure smooth operation.

[0051] After introducing the structure and working principle of the ATM gearbox in the embodiments of this application, the application scenarios of the embodiments of this application are introduced below.

[0052] It should be understood that the gearbox gear self-learning method provided in this application embodiment is mainly applied to the gear shifting process of a vehicle.

[0053] Generally, during vehicle production, due to manufacturing tolerances and assembly variations, even with high-precision manufacturing processes, slight manufacturing tolerances may still exist between different transmissions. These tolerances can lead to differences in the specific mechanical positions of each transmission. Furthermore, during assembly, different assembly workers and techniques may result in slight variations in the positions of internal transmission components.

[0054] Therefore, during vehicle operation, in order to adapt to manufacturing and assembly differences between different vehicles and transmissions, and to improve the smoothness and accuracy of gear shifting, it is generally necessary to control the transmission to perform gear position self-learning. Through gear position self-learning, the transmission can accurately find the optimal position for the shift fork to operate in each gear, control the output torque of the shift motor, and improve the shift response speed.

[0055] Currently, gearbox gear self-learning can be divided into two stages: the motor speed regulation stage and the gear engagement stage. The gear engagement stage can be further divided into stage one and stage two.

[0056] In the motor speed control phase, the ECU is responsible for adjusting the speed of the shift motor to control it and achieve the required response speed. In the gear engagement phase, the ECU is responsible for accurately finding and recording the optimal position for each gear. Phase one can be understood as the rapid response and gear engagement phase, where the ECU quickly pushes the shift fork to approach the target position. Phase two can be understood as the slow gear engagement phase, where the ECU slowly pushes the shift fork until the target position is reached.

[0057] If the engagement sleeve and engagement teeth are in the top tooth state during the gearbox self-learning process, the shift fork will be subjected to a large impact force, causing the shift fork to wear significantly. This will reduce the service life of the shift fork and also lead to inaccurate shifting.

[0058] Based on the above problems, this application proposes a method for gearbox gear self-learning. This method can smoothly disengage the gear and engagement sleeve from the top tooth state by controlling the shift motor during the gearbox gear self-learning process, if the engagement tooth and engagement sleeve are in the top tooth state, thereby avoiding excessive wear of the shift fork and improving the accuracy of gear shift self-learning.

[0059] After introducing the working principle and application scenarios of the gearbox in the embodiments of this application, the following describes a method for gearbox gear self-learning provided by the embodiments of this application.

[0060] Figure 2 This is a schematic flowchart illustrating a method for self-learning gear positions in a transmission according to an embodiment of this application. It should be understood that this method is applied to an ATM transmission, specifically to the ECU within the ATM transmission. Specifically, the method in this embodiment is applied to the gear shifting self-learning process during the gear feeding stage.

[0061] For example, such as Figure 2 As shown, the method 200 includes:

[0062] 201. During the gearbox self-learning process, determine whether the engagement teeth and engagement sleeve are in the top tooth state under the current gear.

[0063] It should be understood that the method in this application aims to improve the success rate of gearbox shift self-learning and avoid excessive wear of the shift fork caused by the engagement sleeve and engagement teeth being in a top-tooth condition during the gear shift self-learning process. Therefore, the method in this application requires timely determination of whether the engagement teeth and engagement sleeve are in a top-tooth condition during the gearbox shift self-learning process.

[0064] It should also be understood that before controlling the transmission gear self-learning, the ECU generally needs to calculate the relevant learning parameters during the transmission gear self-learning process, and then perform self-learning based on the obtained relevant learning parameters. Therefore, before determining whether the engaging teeth are in the top tooth condition, the ECU can first determine the aforementioned relevant learning parameters.

[0065] In one possible implementation, the method further includes:

[0066] Determine the first output torque corresponding to the first gear shifting stage, the second output torque corresponding to the second gear shifting stage, and the critical position of the first gear shifting stage and the second gear shifting stage. The critical position is the position of the shift fork at the end of the first gear shifting stage.

[0067] The transmission performs self-learning based on the first output torque, the second output torque, and the critical position control.

[0068] As mentioned above, the gear shifting process is divided into a first shifting stage and a second shifting stage. The shifting motor outputs a different torque in each shifting stage. Specifically, the second output torque corresponding to the second shifting stage is used to slowly push the shift fork until it reaches the target position.

[0069] In this scenario, if the torque output by the shift motor is too high during the second gear engagement phase, it will cause the shift fork to learn the gear too deeply, resulting in an excessively deep gear engagement. If the shift motor is controlled according to the torque learned from the shift self-learning, the side contact surface between the shift fork and the engagement sleeve will be stressed during driving. This will cause premature wear of the shift fork as mileage increases. Conversely, if the torque output by the shift motor is too low during the second gear engagement phase, it will cause the shift fork to learn the gear too shallowly, resulting in a shallow gear engagement. Due to the conical angle of the engagement sleeve and engagement teeth, this will also cause stress on the other side contact surface between the shift fork and the engagement sleeve, leading to premature wear of the shift fork.

[0070] In addition to the appropriate second output torque, the appropriate critical position also has a crucial impact on shift self-learning. It determines the duration of the second output torque's effect, directly affecting whether the shift fork can move to the optimal position. This critical position refers to the position of the shift fork at the end of the first gear engagement phase.

[0071] For example, the second output torque is generally smaller. If the shift motor operates at the second output torque for a longer period, it may cause the shift self-learning process to fail to engage the next gear. If the shift motor operates at the second output torque for a shorter period and operates at the larger first output torque corresponding to the first gear engagement stage for a longer period, due to inertia, it may easily lead to the shift self-learning position being too deep, resulting in the problem of over-engaging.

[0072] Therefore, when determining the learning parameters, the ECU needs to determine the appropriate first output torque, second output torque, and the position of the shift fork to control the shift motor with the second output torque.

[0073] The process for determining the second output torque is as follows.

[0074] In one possible implementation, the second output torque is determined through the following steps:

[0075] On the test bench, the gear shift motor is controlled to run based on multiple different duty cycles sent by the overriding authority until the shift fork is in the optimal limit position. The duty cycle corresponding to the optimal limit position is recorded as the first duty cycle. The optimal limit position is used to indicate that the engagement teeth and engagement sleeve are fully engaged and the associated gear can rotate.

[0076] The gear shift motor in the vehicle is controlled to operate based on a first duty cycle, and the torque of the gear shift motor under the first duty cycle is determined as the second output torque.

[0077] During the process of determining the relevant learning parameters, the technicians removed the vehicle's transmission and placed it on a test bench.

[0078] Since the movement of the shift fork depends on the rotation of the shift motor, and the position of the shift fork may differ for each gear, technicians can select any gear as the current gear to determine the optimal limit position of the shift fork for each gear.

[0079] Specifically, for the shift motor, Pulse Width Modulation (PWM) determines the motor's speed and output torque, while the output torque determines the position the shift fork can move. Therefore, in the current gear, technicians can send multiple different PWM signals on a test bench to observe the position the shift motor can drive the shift fork to move under different PWM signals, until the shift fork reaches its optimal limit position. The PWM signal corresponding to the optimal limit position is recorded as the first duty cycle. The optimal limit position is the position of the shift fork when the engagement sleeve and engagement teeth are fully engaged, ensuring that the associated gear (i.e., the gear in the gearbox associated with the engagement sleeve and engagement teeth) can still rotate.

[0080] For example, for the optimal limit position, the ECU can acquire the analog voltage signal collected by the position sensor corresponding to the shift motor, and further convert the analog voltage signal into a digital signal to obtain the Analog-to-Digital Conversion Value (AD). The AD value is then used as the position of the shift fork. When the technician determines that the shift fork is in the optimal limit position, the current AD value can be acquired, which is the optimal limit position, and recorded and stored.

[0081] After determining the optimal limit position of the shift fork, which is the ideal or limit position that the shift fork can move to as tested on a test bench, the second output torque of the shift motor is the actual torque output by the shift motor when the vehicle is in operation after the transmission is installed. Therefore, in order to determine the second output torque, the ECU can control the shift motor to operate at the first duty cycle mentioned above, and determine the torque output by the shift motor during operation as the second output torque.

[0082] Optionally, in this embodiment of the application, the first duty cycle can be 10%, and the second output torque is 30mNm.

[0083] After determining the second output torque, the ECU can further determine the critical positions of the first and second gear shift stages. The duration of the critical position must be neither too long nor too short, and must fall between the synchronous position and the optimal limit position.

[0084] In one possible implementation, the critical position is determined through the following steps:

[0085] Determine the synchronization position during the vehicle's transmission history gear self-learning process. The synchronization position is based on the position of the shift fork when the engagement teeth and engagement sleeve are in the top tooth state.

[0086] The critical position is determined based on the optimal limit position and the synchronization position.

[0087] Specifically, the synchronization position refers to the position of the engagement sleeve or shift fork during gear shifting when the rotational speeds of the engagement sleeve and engagement teeth are exactly the same. The synchronization position during the transmission's historical gear self-learning process can be determined by the position of the shift fork when the engagement sleeve and engagement teeth are in the "top tooth" state. The engagement sleeve and engagement teeth being in the "top tooth" state specifically refers to the state where the engagement sleeve has moved axially to its limit, and its inner teeth are in complete contact with the outer teeth of the engagement teeth. In this state, because the inner teeth of the engagement sleeve have already contacted the outer teeth of the engagement teeth, the engagement sleeve can no longer move further.

[0088] The reason why the synchronization position can be determined by the position of the shift fork when the engaging sleeve and engaging teeth are in the top-tooth state is that: when the engaging sleeve and engaging teeth are in the top-tooth state, a large frictional force is generated between the conical friction surface of the synchronization ring and the engaging teeth. This frictional force causes the rotational speeds of the spindle and the engaging teeth to gradually approach consistency, but not yet to reach perfect consistency. Therefore, when the ECU controls the engaging sleeve to retract from the top-tooth state, the frictional force decreases, but a certain amount of friction still exists, causing the rotational speeds of the spindle and the engaging teeth to approach perfect consistency. The position of the shift fork in this state is the synchronization position during the shift self-learning process.

[0089] Optionally, the synchronization position during the transmission's historical gear self-learning process can be obtained by averaging the synchronization positions from multiple historical gear self-learning processes; alternatively, the synchronization position determined in the previous or any historical gear shift process can be used as the synchronization position during the transmission's historical gear self-learning process. The following embodiment of this application uses the synchronization position during the transmission's historical gear self-learning process as the synchronization position from the previous gear shift process as an example for illustration.

[0090] For example, consider the synchronization position during the transmission's historical gear self-learning process. During gear shifting, the shift fork pushes the engagement sleeve to move. When the engagement sleeve and engagement teeth are in the top tooth state, the engagement sleeve cannot move further. Correspondingly, the position of the shift fork or the AD value reflected by the position sensor will no longer change. When the ECU detected that the engagement sleeve and engagement teeth were in the top tooth state during the last gear shift, and the AD value no longer changed, the corresponding position of the shift fork is the position of the shift fork when the engagement teeth and engagement sleeve were in the top tooth state.

[0091] Once the ECU determines that the engagement teeth and engagement sleeve are in the top tooth position, and after the shift fork is in position, the ECU can control the shift motor to retract the engagement sleeve axially. This process is typically achieved by reducing the output torque of the shift motor. During the retraction process, the ECU can monitor the rotational speed of the spindle and engagement teeth in real time via a speed sensor. When the ECU detects that the rotational speeds of the spindle and engagement teeth are perfectly synchronized, it records the AD value of the position sensor at this point, thus obtaining the synchronization position of the transmission during the previous shift.

[0092] After obtaining the optimal limit position and synchronization position of the shift fork, the ECU can determine the critical position of the shift fork based on this.

[0093] In one possible implementation, the steps for determining the critical position are as follows:

[0094] Determine the first position difference based on the optimal extreme position and the synchronous position;

[0095] Based on the preset ratio and the first position difference, determine the second position difference between the critical position and the synchronization position;

[0096] The critical position is determined as the sum of the differences between the synchronous position and the second position.

[0097] Figure 3 This is a schematic diagram of a scenario for determining a critical position provided in an embodiment of this application.

[0098] For example, such as Figure 3 As shown in the diagram, assuming point A represents the synchronization position of the shift fork during the gearbox gear self-learning process, and point B represents the optimal limit position of the shift fork, the ECU can calculate the first position difference, denoted as "ΔT1," based on points B and A. Since the critical position cannot be too close to or too far from the optimal limit position, in this embodiment, a technician can pre-determine the second position difference obtained by multiplying the first position difference by a preset ratio as the difference between the critical position and the synchronization position. Finally, based on the second position difference and the synchronization position, the critical position is obtained.

[0099] Optionally, the preset ratio can be 40%.

[0100] After obtaining the second output torque and the critical position, the ECU can further determine the first output torque.

[0101] In the above technical solution, by determining the critical position through the synchronous position and the optimal limit position, it is possible to provide a suitable and precise timing for torque change during the operation of the shift motor. This ensures that after the shift motor operates at the first output torque and the second output torque, the shift fork can accurately reach the position where the engagement sleeve and engagement teeth are fully engaged, reducing the wear of mechanical parts, preventing inaccurate shifting caused by the gearbox being too deep or too shallow, and improving the success rate of shifting.

[0102] In one possible implementation, the first output torque is determined through the following steps:

[0103] The gear shift motor on the vehicle operates based on the first duty cycle, and the position of the shift fork is recorded as the optimal theoretical position value.

[0104] On the vehicle, the transmission is continuously controlled to perform self-learning based on the second output torque, critical position, and multiple different third output torques corresponding to the first gear shift stage, until the absolute value of the first difference between the optimal position value obtained by the transmission self-learning and the optimal theoretical position value is less than the first threshold. The third output torque corresponding to the optimal position value whose absolute value of the first difference between the optimal theoretical position value and the first threshold value is less than the first threshold value is determined as the first output torque.

[0105] It should be understood that the aforementioned optimal limit position is the ideal or limit position that the shift fork can move to, as tested on a test bench. However, during actual vehicle operation, due to the interaction between mechanical components and the lifespan of these components, the actual operating position of the shift fork may deviate from the optimal limit position. Therefore, when determining the first output torque under vehicle operating conditions, the ECU can first control the vehicle to operate at a first duty cycle, determining the actual limit position of the shift fork during operation under this state, denoted as the "optimal theoretical position value".

[0106] After obtaining the optimal theoretical position value, the ECU can maintain the second output torque and critical position unchanged, and output multiple third output torques during the first gear shift phase. This controls the transmission to perform self-learning, and compares the optimal position value obtained by the transmission after self-learning under each third output torque with the optimal theoretical position value. When the absolute value of the first difference between the optimal position value and the optimal theoretical position value under a certain third output torque is less than a first threshold, it is considered that the self-learning result under that third output torque is not significantly different from the theoretical result, and therefore that third output torque is taken as the first output torque.

[0107] Optionally, the first threshold is 0.1 mm.

[0108] In the above technical solution, when determining the first output torque corresponding to the first gear shift stage, the vehicle has already determined the second output torque and critical position for the second gear shift stage. Therefore, in this application, the vehicle can keep the second output torque and critical position constant, thereby outputting different third output torques to control the shift motor, thus determining the optimal position value of the shift fork obtained after self-learning under different third output torques. Finally, the absolute value of the difference between the optimal position value and the optimal theoretical position value under each third output torque is compared with a threshold to determine if they are close. If they are relatively close, the corresponding third output torque is used as the first output torque. This process ensures precise control of the shift motor during gear shifting by controlling it with torque, ensuring that the shift fork can operate to the optimal position.

[0109] Therefore, after the ECU solves for the relevant learning parameters of the transmission shift self-learning, it can control the transmission to perform gear self-learning based on the first output torque, the second output torque, and the critical position.

[0110] During the gearbox gear self-learning process, the ECU can promptly determine whether the engagement teeth and engagement sleeve are in the top tooth state.

[0111] In one possible implementation, the state of the engaging tooth and the engaging sleeve being in a tooth-attacking state is determined by the following steps:

[0112] During the gearbox's gear self-learning process, the current position of the shift fork and the subsequent position changes of the shift fork are obtained.

[0113] If the current position is greater than the preset position and the duration of the position change being less than the preset change is greater than the preset duration, it is determined that the engaging tooth and the engaging sleeve are not in the top tooth state.

[0114] If the current position is less than or equal to the preset position, or the position change is greater than or equal to the preset change, or the duration of the position change being less than the preset change is less than or equal to the preset duration, then the engaging tooth and engaging sleeve are determined to be in the top tooth state.

[0115] It should be understood that the optimal ideal position value of the shift fork in the current gear has been obtained in advance. For the gear engagement stage, this actually involves the shift fork moving from neutral to synchronized position, and then from synchronized position to the self-learned optimal position value, corresponding to the first and second gear engagement stages. The optimal position value is less than or equal to the optimal ideal position value. Neutral position refers to the position of the shift fork after the shift motor speed adjustment is completed, before it has moved axially; in this position, the engagement sleeve has not yet contacted any gears or synchronizers.

[0116] Therefore, the ECU can pre-determine a preset position based on the positional difference between the shift fork's neutral position and its optimal ideal position. If the shift fork's current position exceeds this preset position during gear self-learning, it indicates that the shift fork's position has exceeded the optimal ideal position, potentially causing the engagement teeth and engagement sleeve to be in a tooth-over-tooth state. Simultaneously, when the engagement sleeve and engagement teeth are in a tooth-over-tooth state, the shift fork cannot move further, resulting in a relatively small change in its position. Therefore, if the ECU determines that the shift fork's current position is greater than the preset position, and the duration of the position change being less than the preset change exceeds a preset duration, then the ECU determines that the engagement sleeve and engagement teeth are in a tooth-over-tooth state. Conversely, if the current position is less than or equal to the preset position, or the position change is greater than or equal to the preset change, or the duration of the position change being less than the preset change is less than or equal to the preset duration, the ECU determines that the engagement sleeve and engagement teeth are not in a tooth-over-tooth state.

[0117] In the above technical solution, during the shift self-learning process, this application also proposes a method to determine whether the engagement sleeve and engagement teeth are in the top tooth state. Specifically, the vehicle monitors the current position of the shift fork and the amount of position change of the shift fork in real time. When the current position of the shift fork is greater than a given preset position and the amount of position change tends to stabilize within a certain period of time, it indicates that the shift fork is in the gear position too deep and cannot move further, and the vehicle determines that the engagement sleeve and engagement teeth are in the top tooth state. The above process can promptly determine whether the engagement sleeve and engagement teeth are in the top tooth state during the shift self-learning process, avoiding mechanical component wear caused by the engagement sleeve and engagement teeth being in the top tooth state for a long time.

[0118] 202. When the engaging teeth and engaging sleeve are in the top tooth state, control the shift motor to enter the torque control mode.

[0119] When the engagement teeth and engagement sleeve are in the top tooth position, the ECU can control the shift motor to enter torque control mode. Torque control mode refers to a mode in which the shift motor adjusts its current according to a set target torque value, thereby controlling the output torque of the shift motor.

[0120] 203. In torque control mode, the shift motor is controlled to operate based on multiple misalignment requests to eliminate the tooth tipping state, wherein the misalignment request is a request in which the rotational speed direction is opposite to the torque direction.

[0121] Once the shift motor enters torque control mode, the ECU can control it to operate with multiple offset requests. Under each offset request, the shift motor's rotational speed is opposite to the torque direction. Specifically, when the shift motor's rotational speed is negative, the torque direction is positive; conversely, when the shift motor's rotational speed is positive, the torque direction is negative.

[0122] Table 1 is an illustrative table showing the correspondence between the rotational speed and torque of multiple misalignment requests for a shift motor provided in an embodiment of this application.

[0123] Table 1

[0124] Rotational speed (rpm) Output torque (Nm) -100 20 -50 20 -10.1 20 -10 20 0 20 5 20 5.1 -20 50 -20 100 -20

[0125] For example, as shown in Table 1, each set of speed and torque corresponds to a set of misalignment requests. When the ECU determines that the engagement sleeve and engagement teeth are in the top tooth state, it can control the shift motor to output the corresponding speed and corresponding torque according to the above multiple misalignment requests.

[0126] Because the rotational direction of the shift motor changes continuously in the aforementioned multiple misalignment requests, the ECU can control the reciprocating motion of the shift motor to induce a "zero-crossing oscillation" phenomenon, thereby causing the engagement teeth and engagement sleeve to exit the top tooth state.

[0127] Zero-crossing oscillation in a shift motor specifically refers to an unstable phenomenon that occurs when the motor's speed approaches or crosses zero. This phenomenon mainly occurs when the shift motor switches from one direction to another, or when the motor is running at low speed.

[0128] The ECU controls the shift motor to rotate back and forth, which can make the shift motor move back and forth slightly at the expected position. This will eventually cause the engagement sleeve and engagement teeth to move back and forth at the position where they stop, resulting in a loosening phenomenon. This will allow the engagement sleeve and engagement teeth to have room to move, i.e., exit the top tooth state.

[0129] Furthermore, during actual vehicle operation, due to wear and tear on mechanical components, the ECU needs to determine whether relevant parameters in the self-learning process need to be redefined.

[0130] In one possible implementation, after the transmission performs self-learning based on the first output torque, the second output torque, and the critical position control, the method further includes:

[0131] When the vehicle's mileage is equal to the first preset mileage, the transmission is controlled to perform the first repeated self-learning based on the first output torque, the second output torque, and the critical position.

[0132] Determine the absolute value of the second difference between the two optimal position values ​​obtained from the first repeated self-learning of the transmission and the previous self-learning;

[0133] If the absolute value of the second difference is less than the second threshold, the transmission operation continues to be controlled based on the first output torque, the second output torque, and the critical position.

[0134] If the absolute value of the second difference is greater than or equal to the second threshold, and the driving mileage is equal to the second preset mileage, the transmission is controlled to perform a second round of self-learning based on the first output torque, the second output torque, and the critical position.

[0135] Determine the absolute value of the third difference between the two optimal position values ​​obtained from the second and first repeated self-learning of the transmission.

[0136] If the absolute value of the third difference is less than the second threshold, the transmission operation continues to be controlled based on the first output torque, the second output torque, and the critical position.

[0137] If the absolute value of the third difference is greater than or equal to the second threshold, the first output torque and the second output torque are updated.

[0138] Specifically, after the vehicle has learned a certain mileage (e.g., 5000 km) using the aforementioned learning parameters, the technician can control the transmission to repeat gear self-learning with the first output torque, second output torque, and critical position to obtain the optimal position (AD value) for this gear self-learning. This optimal AD value is then compared with the optimal AD value obtained from the previous self-learning. If the absolute value of the second difference is less than the second threshold, the self-learning parameters do not need to be updated, and the transmission continues to operate with these parameters. If the absolute value of the second difference is greater than or equal to the second threshold, the transmission is continuously tracked for 2500 km before repeating gear self-learning (corresponding to a second preset mileage of 7500 km) to see if the difference between the optimal AD values ​​obtained from the two repetitions is still within a certain range. If the absolute value of the third difference between the two optimal AD values ​​is less than the second threshold, the self-learning parameters do not need to be updated. If the absolute value of the third difference is greater than or equal to the second threshold, the technician readjusts the output torque for the two gear shifting stages.

[0139] When readjusting the output torque of the two gear shifting stages, the first output torque and the second output torque are determined in accordance with the determination method of the first output torque and the second output torque provided in the aforementioned embodiments of this application.

[0140] In the above technical solution, when the self-learning mileage is long, to verify the stability of the self-learning results, the vehicle can also determine whether the difference between the two most recent optimal position values ​​is too large. If the difference is too large, it indicates that the current self-learning result is no longer stable, and the vehicle can promptly update the output torque of the shift motor to obtain a better shift motor control strategy. If the difference is small, it indicates that the current self-learning process is stabilizing, and the transmission can continue to be controlled to learn with the corresponding parameters. This process allows the output torque to be adjusted according to actual operating conditions during the transmission's self-learning process, improving the adaptability and reliability of the self-learning process.

[0141] The following is combined Figures 4-5 The self-learning effect of gearbox shifting is explained before and after the zero-crossing oscillation strategy is adopted for the aforementioned shifting motor.

[0142] Figure 4 This is a schematic diagram illustrating a scenario where the gearbox fails to learn shifting when the shifting motor does not employ zero-oscillation.

[0143] For example, such as Figure 4As shown, when the engagement sleeve and engagement teeth are in the top tooth state, the gearbox's shift position has not reached its peak value, indicating that the gearbox shifts incompletely. This results in the gearbox failing to shift when the engagement sleeve and engagement teeth are in the top tooth state, without implementing a zero-oscillation strategy for the shift motor.

[0144] Figure 5 This is a schematic diagram illustrating a scenario where the gearbox successfully learns to shift gears when the shift motor uses zero-crossing oscillation, as provided in an embodiment of this application.

[0145] For example, such as Figure 5 As shown, when the engagement sleeve and engagement teeth are in the top tooth state, the ECU requests the shift motor to reciprocate with a torque of ±20Nm, thereby generating zero-crossing oscillation. The transmission reaching its peak engagement position indicates that the transmission is in the correct engagement position and the shift is successful.

[0146] In summary, during the transmission self-learning process, if the engagement teeth and engagement sleeve experience tooth overlap, the vehicle can control the shift motor to enter torque control mode. In torque control mode, the vehicle can control the shift motor to operate based on multiple misalignment requests. These misalignment requests are requests where the shift motor's rotational speed is opposite to the torque direction. For the shift motor, when the rotational speed is opposite to the torque direction, the torque generated during rotation is opposite to the direction of motion. This reverse torque causes the engagement sleeve to move slightly from the tooth overlap position, thereby loosening the stuck engagement teeth and engagement sleeve. Repeating this process multiple times allows the engagement sleeve and engagement teeth to exit the tooth overlap state, ensuring the engagement sleeve smoothly enters the meshing position, avoiding prolonged wear on the shift fork and other mechanical components, and improving the accuracy of the shift fork's movement position. Accurate shifting positions improve shifting reliability, thus increasing the success rate of the transmission's gear position self-learning.

[0147] Figure 6 This is a schematic diagram of the structure of a gearbox gear self-learning device provided in an embodiment of this application.

[0148] For example, such as Figure 6 As shown, the device 600 includes:

[0149] The state determination module 601 is used to determine whether the engagement teeth and engagement sleeve are in the top tooth state when the vehicle's transmission is in the gear self-learning process;

[0150] The mode control module 602 is used to control the shift motor to enter the torque control mode when the engaging tooth and the engaging sleeve are in the top tooth state.

[0151] The operation control module 603 is used to control the shift motor to operate based on multiple misalignment requests in the torque control mode to eliminate the top tooth state, wherein the misalignment request is a request in which the rotational speed direction is opposite to the torque direction.

[0152] Optionally, the device further includes: a parameter determination module, used to determine the first output torque corresponding to the first gear shifting stage, the second output torque corresponding to the second gear shifting stage, and the critical position of the first gear shifting stage and the second gear shifting stage, the critical position being the position of the shift fork at the end of the first gear shifting stage; and to control the transmission to perform self-learning based on the first output torque, the second output torque, and the critical position.

[0153] In one possible implementation, the parameter determination module is specifically used to: control the gear shift motor to operate on a test bench based on multiple different duty cycles sent beyond the authority until the shift fork is in the optimal limit position, record the duty cycle corresponding to the optimal limit position as the first duty cycle, the optimal limit position is used to indicate that the engagement tooth and the engagement sleeve are fully engaged and the associated gear can rotate; control the gear shift motor to operate on the vehicle based on the first duty cycle, and obtain the torque of the gear shift motor under the first duty cycle and determine it as the second output torque.

[0154] In one possible implementation, the parameter determination module is further configured to: determine the synchronization position during the vehicle's transmission history gear self-learning process, the synchronization position being obtained based on the position of the shift fork when the engagement tooth and the engagement sleeve are in the top tooth state; and determine the critical position based on the optimal limit position and the synchronization position.

[0155] In one possible implementation, the parameter determination module is further configured to: control the gear shift motor to operate on the vehicle based on a first duty cycle, and record the position of the shift fork as the optimal theoretical position value; continuously control the transmission to perform self-learning on the vehicle based on the second output torque, the critical position, and multiple different third output torques corresponding to the first gear shift stage, until the absolute value of the first difference between the optimal position value obtained by the transmission after self-learning and the optimal theoretical position value is less than a first threshold, and determine the third output torque corresponding to the optimal position value whose absolute value of the first difference between the optimal theoretical position value and the optimal position value is less than the first threshold as the first output torque.

[0156] In one possible implementation, the state determination module 601 is specifically used to: obtain the current position of the shift fork and the position change of the shift fork at subsequent times during the gear self-learning process of the transmission; determine that the engagement tooth and the engagement sleeve are not in the top tooth state when the current position is greater than a preset position and the duration of the position change being less than the preset change is greater than a preset duration; and determine that the engagement tooth and the engagement sleeve are in the top tooth state when the current position is less than or equal to the preset position, or the position change is greater than or equal to the preset change, or the duration of the position change being less than the preset change is less than or equal to the preset duration.

[0157] Optionally, after the transmission is controlled to perform self-learning based on the first output torque, the second output torque, and the critical position, the device further includes: a torque update module, configured to control the transmission to perform a first repeated self-learning based on the first output torque, the second output torque, and the critical position when the vehicle's mileage equals a first preset mileage; determine the absolute value of a second difference between the first repeated self-learning and the two optimal position values ​​obtained from the previous self-learning; and continue to control the transmission to operate based on the first output torque, the second output torque, and the critical position when the absolute value of the second difference is less than a second threshold; and in the second... If the absolute value of the two differences is greater than or equal to the second threshold, and the mileage is equal to the second preset mileage, the transmission is controlled to perform a second round of self-learning based on the first output torque, the second output torque, and the critical position; the absolute value of the third difference between the two optimal position values ​​obtained from the second round of self-learning and the first round of self-learning is determined; if the absolute value of the third difference is less than the second threshold, the transmission is controlled to continue operating based on the first output torque, the second output torque, and the critical position; if the absolute value of the third difference is greater than or equal to the second threshold, the first output torque and the second output torque are updated.

[0158] Figure 7 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application.

[0159] For example, such as Figure 7 As shown, the vehicle 700 includes a memory 701 and a processor 702. The memory 701 stores executable program code 7011, and the processor 702 is used to call and execute the executable program code 7011 to perform a method for self-learning gear shifts in a transmission.

[0160] Furthermore, embodiments of this application also protect an apparatus that may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to perform a method for self-learning gear positions of a transmission provided in embodiments of this application.

[0161] This embodiment can divide the device into functional modules based on the above method example. For example, each module can correspond to a separate function, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0162] When each functional module is divided according to its corresponding function, the device may further include a state determination module, a mode control module, and an operation control module. It should be noted that all relevant content regarding the steps involved in the above method embodiments can be referenced from the functional descriptions of the corresponding functional modules, and will not be repeated here.

[0163] It should be understood that the device provided in this embodiment is used to execute the above-described method for self-learning gear positions in a transmission, and therefore can achieve the same effect as the above-described implementation method.

[0164] When using an integrated unit, the device may include a processing module and a storage module. When the device is applied to a vehicle, the processing module can be used to control and manage the vehicle's movements. The storage module can be used to support the vehicle in executing relevant program code.

[0165] The processing module may be a processor or a controller, which can implement or execute various exemplary logic blocks, modules, and circuits shown in conjunction with the disclosure of this application. The processor may also be a combination of functions that implement computing capabilities, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc., and the storage module may be a memory.

[0166] In addition, the device provided in the embodiments of this application may specifically be a chip, component or module. The chip may include a connected processor and a memory. The memory is used to store instructions. When the processor calls and executes the instructions, the chip can execute a gearbox gear self-learning method provided in the above embodiments.

[0167] This embodiment also provides a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the above-described related method steps to implement a gearbox gear self-learning method provided in the above embodiment.

[0168] This embodiment also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned related steps to implement a gearbox gear self-learning method provided in the above embodiment.

[0169] In this embodiment, the device, computer-readable storage medium, computer program product, or chip are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0170] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0171] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0172] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for self-learning gear positions in a transmission, characterized in that, The method includes: During the gearbox self-learning process, determine whether the engagement teeth and engagement sleeve are in the top tooth state under the current gear. When the engaging tooth and the engaging sleeve are in the top tooth state, control the shift motor to enter the torque control mode; In the torque control mode, the shift motor is controlled to operate based on multiple misalignment requests to eliminate the top tooth state, wherein the misalignment request is a request in which the rotational speed direction is opposite to the torque direction.

2. The method according to claim 1, characterized in that, The method further includes: Determine the first output torque corresponding to the first gear shifting stage, the second output torque corresponding to the second gear shifting stage, and the critical position between the first gear shifting stage and the second gear shifting stage. The critical position is the position of the shift fork at the end of the first gear shifting stage. The transmission is controlled to perform self-learning based on the first output torque, the second output torque, and the critical position.

3. The method according to claim 2, characterized in that, The second output torque is determined through the following steps: On the test bench, the gear shift motor is controlled to operate based on multiple different duty cycles sent in an unauthorized manner until the shift fork is in the optimal limit position. The duty cycle corresponding to the optimal limit position is recorded as the first duty cycle. The optimal limit position is used to indicate that the engagement tooth and the engagement sleeve are fully engaged and the associated gear can rotate. The gear shift motor is controlled to operate based on a first duty cycle on the vehicle, and the torque of the gear shift motor under the first duty cycle is obtained and determined as the second output torque.

4. The method according to claim 3, characterized in that, The critical position is determined through the following steps: The synchronization position during the vehicle's transmission history gear self-learning process is determined, and the synchronization position is obtained based on the position of the shift fork when the engagement tooth and the engagement sleeve are in the top tooth state; The critical position is determined based on the optimal limit position and the synchronization position.

5. The method according to claim 4, characterized in that, The first output torque is determined through the following steps: On the vehicle, the gear shift motor is controlled to operate based on a first duty cycle, and the position of the shift fork is recorded as the optimal theoretical position value. On the vehicle, the transmission is continuously controlled to perform self-learning based on the second output torque, the critical position, and multiple different third output torques corresponding to the first gear shift stage, until the absolute value of the first difference between the optimal position value obtained by the transmission after self-learning and the optimal theoretical position value is less than a first threshold. The third output torque corresponding to the optimal position value whose absolute value of the first difference between the optimal theoretical position value and the first threshold value is less than the first threshold value is determined as the first output torque.

6. The method according to claim 1, characterized in that, Whether the engaging tooth and the engaging sleeve are in a tooth-interlocking state is determined by the following steps: During the gearbox's gear self-learning process, the current position of the shift fork and the change in the position of the shift fork at subsequent times are obtained. If the current position is greater than the preset position, and the duration for which the position change is less than the preset change is greater than the preset duration, it is determined that the engaging tooth and the engaging sleeve are not in the top tooth state. If the current position is less than or equal to the preset position, or the position change is greater than or equal to the preset change, or the duration during which the position change is less than the preset change is less than or equal to the preset duration, then the engaging tooth and the engaging sleeve are determined to be in the top tooth state.

7. The method according to claim 2, characterized in that, After the method involves controlling the transmission to perform self-learning based on the first output torque, the second output torque, and the critical position, the method further includes: When the vehicle's mileage is equal to the first preset mileage, the transmission is controlled to perform the first repeated self-learning based on the first output torque, the second output torque, and the critical position. Determine the absolute value of the second difference between the two optimal position values ​​obtained from the first repeated self-learning of the transmission and the previous self-learning; If the absolute value of the second difference is less than the second threshold, the transmission continues to be controlled based on the first output torque, the second output torque, and the critical position. If the absolute value of the second difference is greater than or equal to the second threshold, and the driving mileage is equal to the second preset mileage, the transmission is controlled to perform a second repeated self-learning based on the first output torque, the second output torque and the critical position. Determine the absolute value of the third difference between the two optimal position values ​​obtained from the second repeated self-learning of the transmission and the first repeated self-learning; If the absolute value of the third difference is less than the second threshold, the transmission continues to be controlled based on the first output torque, the second output torque, and the critical position. If the absolute value of the third difference is greater than or equal to the second threshold, the first output torque and the second output torque are updated.

8. A device for self-learning gear positions in a transmission, characterized in that, The device includes: The state determination module is used to determine whether the engagement teeth and engagement sleeve are in the top tooth state when the vehicle's transmission is in the gear self-learning process; The mode control module is used to control the shift motor to enter the torque control mode when the engaging tooth and the engaging sleeve are in the top tooth state. The operation control module is used to control the shift motor to operate based on multiple misalignment requests in the torque control mode to eliminate the top tooth state, wherein the misalignment request is a request in which the rotational speed direction is opposite to the torque direction.

9. A vehicle, characterized in that, The vehicles include: Memory, used to store executable program code; A processor for calling and running the executable program code from the memory, causing the vehicle to perform the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the method as described in any one of claims 1 to 7.

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