An automatic transmission off-line self-learning and calibration system and its working method

Abstract

An automatic transmission off-line self-learning and calibration system and its working method belong to the field of automatic transmission technology. The system initialization includes: drive motor startup; initial oil supply pressure setting; increasing clutch oil supply pressure at a constant slope; torque and speed signal acquisition and uploading; determining whether the rate of change of torque exceeds a preset threshold; recording the current oil supply pressure; continuing to increase the oil supply pressure; determining whether the output torque reaches a preset target torque; recording the current oil supply pressure; generating a clutch curve and writing it to memory; and completing all clutch self-learning and calibration. This invention achieves high-precision, fully automatic self-learning and calibration of the automatic transmission at the end of the production line by locking the transmission output shaft and accurately measuring the pressure-torque characteristics of the clutch under static conditions. This improves production efficiency, ensures the consistency of transmission control parameters, and effectively enhances product quality.

Description

Technical Field

[0001] This invention relates to an automatic transmission off-line self-learning and calibration system and its working method, belonging to the field of automatic transmission technology. Background Technology

[0002] Automatic transmissions are a core component of modern automobiles, and their performance directly determines the smoothness of driving, fuel economy, and reliability of the entire vehicle. After the automatic transmission is assembled, due to manufacturing tolerances and initial wear differences in its internal friction components such as clutches and brakes, as well as individual performance differences in the hydraulic system, the actual operating characteristics (such as clutch engagement point and torque transmission capability) of each transmission are different.

[0003] To ensure transmission control accuracy and product consistency, each transmission must undergo self-learning and parameter calibration before leaving the factory, and key control parameters must be written into the TCU (Transmission Control Unit).

[0004] In existing technologies, self-learning methods usually rely on vehicle road tests, which are inefficient and have poor consistency in calibration results. This makes it difficult to meet the requirements of mass production for production efficiency and product quality. Therefore, there is an urgent need for a technical solution that can achieve high-precision, fully automatic self-learning and calibration at the end of the production line. Summary of the Invention

[0005] To address the problems existing in the background art, the present invention provides an automatic transmission off-line self-learning and calibration system and its working method.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: an automatic transmission off-line self-learning and calibration system, comprising...

[0007] Offline testing bench is used to fix the automatic transmission under test, providing an installation support platform for the self-learning and calibration process;

[0008] The drive motor is used to provide power to the input shaft of the gearbox and precisely control the speed and torque output.

[0009] A torque sensor is used to acquire the output torque signal of the drive motor in real time to ensure the accuracy of signal acquisition.

[0010] A speed sensor is used to acquire the output speed signal of the drive motor in real time to ensure the accuracy of signal acquisition;

[0011] A rigid locking mechanism is used to securely lock the transmission output shaft, providing stable conditions for static measurements.

[0012] The hydraulic supply system is used to supply hydraulic oil to the various clutches of the transmission to meet pressure regulation requirements;

[0013] The TCU is used to store clutch pressure-torque related parameters obtained during self-learning and calibration, and to achieve precise control of the clutch based on these parameters during actual operation of the transmission.

[0014] The data acquisition and control layer includes a data acquisition unit responsible for receiving sensor signals and uploading them to the central processing unit, a central industrial control computer with built-in control algorithms that achieve bidirectional communication with the TCU through a communication unit, and a data storage device for temporarily storing various types of acquired data.

[0015] The present invention discloses a working method for an automatic transmission off-line self-learning and calibration system, the method comprising the following steps:

[0016] S1: System initialization;

[0017] S2: The central processing unit sends a control command to the drive motor, which starts and runs to the idle speed, while controlling its torque output to be zero.

[0018] S3: Connect the oil supply channel of the target clutch through the hydraulic supply system to supply oil to the target clutch. The initial oil supply pressure is set to... ;

[0019] S4: The hydraulic supply system operates at a preset constant pressure change slope. Continuously increase the oil supply pressure of the target clutch, where: This is the change in pressure. It is a quantity that changes over time;

[0020] S5: Torque and speed signal acquisition and uploading;

[0021] S6: The central processing unit analyzes the acquired torque signal and determines the rate of change of torque T. Check if the preset threshold A is exceeded, and at the same time determine if the speed of the drive motor has dropped more than the preset threshold B; if both judgment conditions are met, execute S7; if either judgment condition is not met, return to S4 and continue to increase the oil supply pressure of the target clutch until the condition is met.

[0022] S7: Record the current oil supply pressure of the target clutch, which is the initial contact pressure of the target clutch;

[0023] S8: The hydraulic supply system continues to increase the oil supply pressure of the target clutch, and the torque sensor and speed sensor continuously collect torque signals and upload them;

[0024] S9: The central processing unit determines whether the collected output torque T of the drive motor has reached the preset target torque. The torque value stabilizes for a certain period of time; if this condition is met, proceed to step S10; if not, return to step S8 and continue increasing the pressure until the target requirement is met.

[0025] S10: Record the current oil supply pressure of the target clutch. This pressure is the target clutch's oil supply pressure at the target torque. The full locking pressure below;

[0026] S11: The central processing unit summarizes all data points collected during the entire pressure regulation process, processes the data using a fitting algorithm, and generates the pressure-torque characteristic curve of the target clutch.

[0027] S12: The central processing unit writes the acquired raw data, initial contact pressure, full locking pressure, and fitting parameters of the characteristic curve into the TCU's non-volatile memory via the CAN bus.

[0028] S13: The central processing unit determines whether all clutches in the transmission that need self-learning have completed the operations of S2-S12. If all have completed, the self-learning and calibration process ends. If not all have completed, the hydraulic supply channel is switched to the next clutch to be calibrated and S2-S12 is repeated until all clutches have completed self-learning and calibration.

[0029] Furthermore, step S1 includes the following steps:

[0030] S101: System power-on initialization;

[0031] S102: Fix the automatic transmission under test on the offline testing bench, connect the transmission input shaft to the drive motor output end through a coupling, and lock the transmission output shaft through a rigid locking mechanism;

[0032] S103: Connect the oil outlet of the hydraulic supply system to the clutch oil supply passage of the transmission;

[0033] S104: The data acquisition unit is connected to the torque sensor, speed sensor and central processing unit respectively. The central processing unit establishes a communication connection with the TCU through the CAN bus, and then connects the system power to complete the equipment deployment and power-on.

[0034] S105: The central processing unit sends a communication initialization command to the TCU. After the TCU responds, the two parties establish stable communication. The central processing unit performs initialization settings for the drive motor, hydraulic supply system, and data acquisition unit.

[0035] Furthermore, step S5 includes the following steps:

[0036] S501: Real-time acquisition of the output torque T of the drive motor via a torque sensor;

[0037] S502: Real-time acquisition of the drive motor speed signal via a speed sensor;

[0038] S503: The acquired torque and speed signals are converted into digital signals by the data acquisition unit and then uploaded to the central processing unit.

[0039] Furthermore, the signal acquisition frequency of the torque sensor and speed sensor mentioned in S501 and S502 is not less than 100Hz.

[0040] Furthermore, the torque T mentioned in S9 is stabilized at the target torque. The determination condition is: the torque value remains stable for no less than 3 seconds.

[0041] Compared with the prior art, the beneficial effects of the present invention are:

[0042] This invention addresses the shortcomings of existing automatic transmission self-learning methods, which rely on vehicle road testing, are inefficient, and have poor consistency in calibration results. By locking the transmission output shaft, it accurately measures the pressure-torque characteristics of the clutch under static conditions, achieving high-precision, fully automated self-learning and calibration of the automatic transmission at the end of the production line. This not only improves production efficiency but also ensures the consistency of transmission control parameters, effectively improving product quality. Attached Figure Description

[0043] Figure 1 This is a flowchart of the working method of the present invention;

[0044] Figure 2 This is a structural block diagram of the system of the present invention. Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0046] An automatic transmission off-line self-learning and calibration system, including

[0047] Offline testing bench is used to fix the automatic transmission under test, providing an installation support platform for the self-learning and calibration process;

[0048] The drive motor is used to provide power to the input shaft of the gearbox and precisely control the speed and torque output.

[0049] A torque sensor is used to acquire the output torque signal of the drive motor in real time to ensure the accuracy of signal acquisition.

[0050] A speed sensor is used to acquire the output speed signal of the drive motor in real time to ensure the accuracy of signal acquisition;

[0051] The rigid locking mechanism, using hydraulic clamps, is used to firmly lock the transmission output shaft, providing stable conditions for static measurement;

[0052] The hydraulic supply system is used to provide controllable and stable hydraulic oil to each clutch of the transmission to meet pressure regulation requirements;

[0053] The TCU is used to store clutch pressure-torque related parameters obtained during self-learning and calibration, and to achieve precise control of the clutch based on these parameters during actual operation of the transmission.

[0054] The data acquisition and control layer includes a data acquisition unit (data acquisition card) responsible for receiving sensor signals and uploading them to the central processing unit (central industrial control computer), a central industrial control computer with built-in control algorithms that achieve bidirectional communication with the TCU through a communication unit (CAN bus), and a data storage device for temporarily storing various types of acquired data.

[0055] The present invention discloses a working method for an automatic transmission off-line self-learning and calibration system, the method comprising the following steps:

[0056] S1: System initialization;

[0057] S2: The central processing unit sends control commands to the drive motor, which starts and runs to the idle speed, while controlling its torque output to be zero to maintain a stable working state.

[0058] S3: Connect the oil supply channel of the target clutch (such as 1st gear clutch C1) through the hydraulic supply system to supply oil to the target clutch. The initial oil supply pressure is set to... , The lower safety pressure determined through preliminary testing can prevent abnormal clutch wear caused by excessively high initial pressure.

[0059] S4: The hydraulic supply system operates at a preset constant pressure change slope. (This slope is determined based on the characteristics of the transmission clutch to ensure smooth pressure changes.) Slowly and continuously increase the oil supply pressure of the target clutch, where: This is the change in pressure. It is a quantity that changes over time;

[0060] S5: Torque and speed signal acquisition and uploading;

[0061] S6: The central processing unit analyzes the acquired torque signal and determines the rate of change of torque T. Check if the preset threshold A is exceeded (threshold A is preset according to the clutch type and torque transmission characteristics), and at the same time check if the speed of the drive motor has dropped beyond the preset threshold B (threshold B is determined according to the idle speed range); if both judgment conditions are met, it is determined that the clutch has reached the initial contact state, and then execute S7; if either judgment condition is not met, return to S4 and continue to increase the oil supply pressure of the target clutch until the condition is met.

[0062] S7: Record the current oil supply pressure of the target clutch, which is the initial contact pressure of the target clutch;

[0063] S8: The hydraulic supply system continues to increase the oil supply pressure of the target clutch, and the torque sensor and speed sensor continuously collect torque signals and upload them;

[0064] S9: The central processing unit determines whether the collected output torque T of the drive motor has reached the preset target torque. ( The torque value is determined based on the transmission design torque parameters and remains stable for a certain period of time (more than 3 seconds to ensure torque stability and avoid instantaneous fluctuations affecting the judgment); if this condition is met, proceed to S10; if not, return to S8 and continue to increase the pressure until the target requirement is met.

[0065] S10: Record the current oil supply pressure of the target clutch. This pressure is the target clutch's oil supply pressure at the target torque. The full locking pressure below;

[0066] S11: The central processing unit summarizes all (pressure, torque) data points collected during the entire pressure regulation process, processes the data using the least squares fitting algorithm, and generates the pressure-torque characteristic curve of the target clutch to ensure that the curve can accurately reflect the torque transmission capability of the clutch under different pressures.

[0067] S12: The central processing unit writes the acquired raw data, initial contact pressure, full lock-up pressure, and fitting parameters of the characteristic curve (such as slope, intercept, etc.) into the TCU's non-volatile memory via the CAN bus. These parameters will serve as the control basis for the operation of the transmission and complete the calibration of the clutch.

[0068] S13: The central processing unit determines whether all clutches in the transmission that need self-learning (such as other gear clutches, brakes, etc.) have completed the above S2-S12 operations; if all have completed, the self-learning and calibration process ends; if not all have completed, the hydraulic supply channel is switched to the next clutch to be calibrated and S2-S12 is repeated until all clutches have completed self-learning and calibration.

[0069] Furthermore, step S1 includes the following steps:

[0070] S101: System power-on initialization;

[0071] S102: Fix the automatic transmission under test on the offline testing bench, connect the input shaft of the transmission to the output end of the drive motor through a coupling, and firmly lock the output shaft of the transmission through a rigid locking mechanism to ensure no relative rotation;

[0072] S103: Connects the oil outlet of the hydraulic supply system to the clutch oil supply passage of the transmission to provide controllable hydraulic oil to the transmission;

[0073] S104: The data acquisition unit is connected to the torque sensor, speed sensor and central processing unit respectively. The central processing unit establishes a communication connection with the TCU through the CAN bus, and then connects the system power to complete the equipment deployment and power-on.

[0074] S105: The central processing unit sends a communication initialization command to the TCU. After the TCU responds, the two parties establish stable communication. The central processing unit initializes the drive motor, hydraulic supply system, and data acquisition unit to ensure that each device is in a ready-to-work state.

[0075] Furthermore, step S5 includes the following steps:

[0076] S501: Real-time acquisition of the output torque T of the drive motor via a torque sensor;

[0077] S502: Real-time acquisition of the drive motor speed signal via a speed sensor;

[0078] S503: The acquired torque and speed signals are converted into digital signals by the data acquisition unit and then uploaded to the central processing unit.

[0079] Furthermore, the signal acquisition frequency of the torque sensor and speed sensor mentioned in S501 and S502 is not less than 100Hz to ensure the real-time performance of the signals.

[0080] Furthermore, the torque T mentioned in S9 is stabilized at the target torque. The determination condition is: the torque value remains stable for no less than 3 seconds.

[0081] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of the equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0082] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An automatic transmission off-line self-learning and calibration system, characterized in that: include: Offline testing bench is used to fix the automatic transmission under test, providing an installation support platform for the self-learning and calibration process; The drive motor is used to provide power to the input shaft of the gearbox and precisely control the speed and torque output. A torque sensor is used to acquire the output torque signal of the drive motor in real time to ensure the accuracy of signal acquisition. A speed sensor is used to acquire the output speed signal of the drive motor in real time to ensure the accuracy of signal acquisition; A rigid locking mechanism is used to securely lock the transmission output shaft, providing stable conditions for static measurements. The hydraulic supply system is used to supply hydraulic oil to the various clutches of the transmission to meet pressure regulation requirements; The TCU is used to store clutch pressure-torque related parameters obtained during self-learning and calibration, and to achieve precise control of the clutch based on these parameters during actual operation of the transmission. The data acquisition and control layer includes a data acquisition unit responsible for receiving sensor signals and uploading them to the central processing unit, a central industrial control computer with built-in control algorithms that achieve bidirectional communication with the TCU through a communication unit, and a data storage device for temporarily storing various types of acquired data.

2. A method for operating the automatic transmission off-line self-learning and calibration system according to claim 1, characterized in that: The method includes the following steps: S1: System initialization; S2: The central processing unit sends a control command to the drive motor, which starts and runs to the idle speed, while controlling its torque output to be zero. S3: Connect the oil supply channel of the target clutch through the hydraulic supply system to supply oil to the target clutch. The initial oil supply pressure is set to... ; S4: The hydraulic supply system operates at a preset constant pressure change slope. Continuously increase the oil supply pressure of the target clutch, where: This is the change in pressure. It is a quantity that changes over time; S5: Torque and speed signal acquisition and uploading; S6: The central processing unit analyzes the acquired torque signal and determines the rate of change of torque T. Check if the preset threshold A is exceeded, and at the same time determine if the speed of the drive motor has dropped more than the preset threshold B; if both judgment conditions are met, execute S7; if either judgment condition is not met, return to S4 and continue to increase the oil supply pressure of the target clutch until the condition is met. S7: Record the current oil supply pressure of the target clutch, which is the initial contact pressure of the target clutch; S8: The hydraulic supply system continues to increase the oil supply pressure of the target clutch, and the torque sensor and speed sensor continuously collect torque signals and upload them; S9: The central processing unit determines whether the collected output torque T of the drive motor has reached the preset target torque. The torque value stabilizes for a certain period of time; if this condition is met, proceed to step S10; if not, return to step S8 and continue increasing the pressure until the target requirement is met. S10: Record the current oil supply pressure of the target clutch. This pressure is the target clutch's oil supply pressure at the target torque. The full locking pressure below; S11: The central processing unit summarizes all data points collected during the entire pressure regulation process, processes the data using a fitting algorithm, and generates the pressure-torque characteristic curve of the target clutch. S12: The central processing unit writes the acquired raw data, initial contact pressure, full locking pressure, and fitting parameters of the characteristic curve into the TCU's non-volatile memory via the CAN bus. S13: The central processing unit determines whether all clutches in the transmission that need self-learning have completed the operations of S2-S12. If all have completed, the self-learning and calibration process ends. If not all have completed, the hydraulic supply channel is switched to the next clutch to be calibrated and S2-S12 is repeated until all clutches have completed self-learning and calibration.

3. The method according to claim 2, characterized in that: S1 includes the following steps: S101: System power-on initialization; S102: Fix the automatic transmission under test on the offline testing bench, connect the transmission input shaft to the drive motor output end through a coupling, and lock the transmission output shaft through a rigid locking mechanism; S103: Connect the oil outlet of the hydraulic supply system to the clutch oil supply passage of the transmission; S104: The data acquisition unit is connected to the torque sensor, speed sensor and central processing unit respectively. The central processing unit establishes a communication connection with the TCU through the CAN bus, and then connects the system power to complete the equipment deployment and power-on. S105: The central processing unit sends a communication initialization command to the TCU. After the TCU responds, the two parties establish stable communication. The central processing unit performs initialization settings for the drive motor, hydraulic supply system, and data acquisition unit.

4. The method according to claim 2, characterized in that: S5 includes the following steps: S501: Real-time acquisition of the output torque T of the drive motor via a torque sensor; S502: Real-time acquisition of the drive motor speed signal via a speed sensor; S503: The acquired torque and speed signals are converted into digital signals by the data acquisition unit and then uploaded to the central processing unit.

5. The method according to claim 4, characterized in that: The signal acquisition frequency of the torque sensor and speed sensor described in S501 and S502 is not less than 100Hz.

6. The method according to claim 2, characterized in that: The torque T mentioned in S9 is stabilized at the target torque. The determination condition is: the torque value remains stable for no less than 3 seconds.

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