Reliability test method for AMT gear position displacement sensor

Abstract

The present invention relates to a reliability inspection method for an AMT gear displacement sensor, comprising the steps of: obtaining the current running state of the whole vehicle; if the vehicle is in a stationary state or in a gear shifting process, returning and executing again; if the vehicle is in a running state and the gear shifting is completed, executing the next step; obtaining gear position information of a transmission, shaft speed information, and vehicle operating condition information; obtaining current gear information; obtaining a theoretical speed ratio; calculating an actual speed ratio; comparing the theoretical speed ratio with the actual speed ratio: if the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is less than a speed ratio deviation threshold, determining that the gear displacement sensor signal is credible and valid; otherwise determining that the gear displacement sensor signal is uncredible and invalid; entering an artificially preset fault response mechanism; the present invention does not need to increase monitoring lines to fully load functional safety requirements, does not increase the circuit logic complexity of the whole vehicle, and does not increase the possibility of errors in the on-board electrical signal system.

Description

Technical Field

[0001] The present invention relates to the technical field of displacement sensor fault detection methods, and in particular to a reliability inspection method for an AMT gear position displacement sensor. Background Art

[0002] The gear displacement signal of AMT is a parameter that reflects the movement position of the gearbox fork shaft. The only direct source is the measurement of the gear displacement sensor, including gear selection displacement, gear shifting displacement, front sub-box displacement, and rear sub-box displacement, etc. The movement position of the fork shaft can directly reflect the actual gear meshing condition of the gearbox, that is, the gear position currently engaged in the gearbox can be determined through the gear displacement signal. If the displacement signal fails, the current gear position of the gearbox cannot be obtained, which will affect the gear control of the gearbox. Since the available sources are relatively single, in order to reduce the risk of sensor failure, a reliability test method for the displacement sensor is specially designed to provide the detectability of sensor failure.

[0003] like Figure 1 As shown, the gearbox operating mechanism controls the movement of the shift fork shaft, thereby driving the shift fork to move, and then controlling the engagement and disengagement of the shift gear. By monitoring the displacement of the fork shaft through the displacement sensor, it can be determined whether the gearbox is in a gear engagement state and the specific gear engaged. Through two speed sensors, the current input shaft speed and output shaft speed can be monitored in real time.

[0004] However, the above monitoring is based on a premise that all sensors are working properly without considering the reliability issue; and most existing AMTs do not take the reliability verification of sensors into consideration;

[0005] The disadvantages of doing this are:

[0006] Since reliability verification is not performed, the reliability of the displacement signal cannot be guaranteed, which poses a functional safety risk;

[0007] Currently, there are a few existing technologies that perform sensor reliability verification on AMT. The technical solutions used are similar and the principles are the same, which are to add various auxiliary sensors or monitoring equipment to collect and verify the reliability of displacement signals. The existing technologies can indeed solve the safety risks caused by not performing reliability verification.

[0008] The defects of the prior art are:

[0009] 1. Due to the lack of a reference source for the reliability verification of the displacement sensor, it is necessary to add monitoring circuits in hardware to fully meet the functional safety requirements, thereby increasing the complexity of the circuit logic of the entire vehicle, further increasing the possibility of errors in the on-board electrical signal system, and further increasing the resource consumption of computing devices such as ECU and EECU;

[0010] 2. Since it is necessary to add monitoring circuits in hardware to fully meet functional safety requirements, the costs of the entire vehicle from design to manufacturing and subsequent maintenance are increased. Summary of the invention

[0011] In response to the above-mentioned problems, the present invention provides a reliability inspection method for an AMT gear displacement sensor, the purpose of which is to meet the functional safety requirements without adding monitoring lines, without increasing the circuit logic complexity of the entire vehicle, without increasing the possibility of errors in the on-board electrical signal system, and without increasing the resource consumption of computing devices such as ECU and EECU.

[0012] To solve the above problems, the technical solution provided by the present invention is:

[0013] A reliability test method for an AMT gear displacement sensor comprises the following steps:

[0014] S100. Obtain the current vehicle operation state; the vehicle operation state includes the vehicle stationary state, the state during the gear shifting process, and the vehicle running and the gear shifting completed state; then perform the following operations according to the vehicle operation state:

[0015] If the vehicle operation state is the vehicle stationary state or the state in the gear shifting process, return to and execute S100 again;

[0016] If the vehicle operation state is the vehicle operation and gear shifting is completed state, execute S200;

[0017] S200. Obtaining gearbox position information, shaft speed information, and vehicle operating condition information;

[0018] S300. According to the gear position information of the transmission, the current gear information is obtained; then, according to the current gear information and the gear position information of the transmission, the theoretical speed ratio is obtained;

[0019] S400. Calculate the actual speed ratio according to the shaft speed information;

[0020] S500. Compare the theoretical speed ratio with the actual speed ratio, and perform the following operations according to the comparison result:

[0021] If the comparison result is that the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is less than the manually preset speed ratio deviation threshold, it is determined that the gear displacement sensor signal is credible and valid; then S700 is executed;

[0022] If the comparison result is that the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is greater than the speed ratio deviation threshold, it is determined that the gear displacement sensor signal is unreliable and invalid; then S600 is executed;

[0023] S600. Enter the manually preset fault response mechanism; then execute S700;

[0024] S700. Exit this reliability test.

[0025] Preferably, the gearbox gear position information includes gear selection displacement, gear shift displacement, front auxiliary gearbox displacement, and rear auxiliary gearbox displacement;

[0026] The shaft speed information includes the gearbox intermediate shaft speed, gearbox main shaft speed, gearbox input shaft speed, and gearbox output shaft speed;

[0027] The theoretical speed ratio includes the main box theoretical speed ratio, the front auxiliary box theoretical speed ratio, and the rear auxiliary box theoretical speed ratio;

[0028] The actual speed ratio includes the actual speed ratio of the intermediate shaft to the main shaft, the actual speed ratio of the input shaft to the intermediate shaft, and the actual speed ratio of the main shaft to the output shaft;

[0029] The speed ratio deviation includes the main box theoretical-actual speed ratio deviation, the front auxiliary box theoretical-actual speed ratio deviation, and the rear auxiliary box theoretical-actual speed ratio deviation;

[0030] The speed ratio deviation thresholds include a main gearbox theoretical-actual speed ratio deviation threshold, a front auxiliary gearbox theoretical-actual speed ratio deviation threshold, and a rear auxiliary gearbox theoretical-actual speed ratio deviation threshold;

[0031] The vehicle operating condition information includes vehicle speed, rear axle speed ratio, tire rolling radius, and engine speed information; the engine speed information includes engine speed;

[0032] The gear position displacement sensor signal includes a gearbox shift displacement sensor signal, a gearbox front auxiliary box displacement sensor signal, and a gearbox rear auxiliary box displacement sensor signal.

[0033] Preferably, the actual speed ratio of the intermediate shaft to the main shaft is expressed as follows:

[0034]

[0035] Where: η4 is the actual speed ratio of the intermediate shaft to the main shaft; r mid is the gearbox intermediate shaft speed; r main is the gearbox main shaft speed.

[0036] Preferably, the actual speed ratio of the input shaft to the intermediate shaft is expressed as follows:

[0037]

[0038] Where: η5 is the actual speed ratio of the input shaft to the intermediate shaft; r input is the gearbox input shaft speed; the gearbox input shaft speed is expressed as follows:

[0039] r input =r engine

[0040] Where: r engine is the engine speed in the engine speed information.

[0041] Preferably, the actual speed ratio of the main shaft to the output shaft is expressed as follows:

[0042]

[0043] Where: η6 is the actual speed ratio of the main shaft to the output shaft; r output is the transmission output shaft speed; the transmission output shaft speed is calculated based on the vehicle speed, the rear axle speed ratio, and the tire rolling radius in the vehicle operating condition information.

[0044] Preferably, the main box theoretical-actual speed ratio deviation is expressed as follows:

[0045]

[0046] Wherein: δ1 is the theoretical-actual speed ratio deviation of the main box; η1 is the theoretical speed ratio of the main box.

[0047] Preferably, the theoretical-actual speed ratio deviation of the front auxiliary box is expressed as follows:

[0048]

[0049] Wherein: δ2 is the theoretical-actual speed ratio deviation of the front auxiliary box; η2 is the theoretical speed ratio of the front auxiliary box.

[0050] Preferably, the theoretical-actual speed ratio deviation of the rear auxiliary box is expressed as follows:

[0051]

[0052] Wherein: δ3 is the theoretical-actual speed ratio deviation of the rear auxiliary box; η3 is the theoretical speed ratio of the rear auxiliary box.

[0053] Preferably, comparing the theoretical speed ratio with the actual speed ratio in S500 specifically includes the following steps:

[0054] S510. Compare the main box theoretical-actual speed ratio deviation with the main box theoretical-actual speed ratio deviation threshold; then perform the following operations according to the comparison result:

[0055] If the master box theoretical-actual speed ratio deviation is less than the master box theoretical-actual speed ratio deviation threshold, it is determined that the gearbox shift displacement sensor signal is credible and valid; then S520 is executed;

[0056] If the master box theoretical-actual speed ratio deviation is greater than the master box theoretical-actual speed ratio deviation threshold, it is determined that the gearbox shift displacement sensor signal is unreliable and invalid; then S520 is executed;

[0057] S520. Compare the front auxiliary box theoretical-actual speed ratio deviation with the front auxiliary box theoretical-actual speed ratio deviation threshold; then perform the following operations according to the comparison result:

[0058] If the front auxiliary box theoretical-actual speed ratio deviation is less than the front auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission front auxiliary box displacement sensor signal is credible and valid; then S530 is executed;

[0059] If the front auxiliary box theoretical-actual speed ratio deviation is greater than the front auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission front auxiliary box displacement sensor signal is unreliable and invalid; then S530 is executed;

[0060] S530. Compare the rear auxiliary box theoretical-actual speed ratio deviation with the rear auxiliary box theoretical-actual speed ratio deviation threshold; and then perform the following operations according to the comparison result:

[0061] If the rear auxiliary box theoretical-actual speed ratio deviation is less than the rear auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission rear auxiliary box displacement sensor signal is credible and valid; then S540 is executed;

[0062] If the rear auxiliary box theoretical-actual speed ratio deviation is greater than the rear auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission rear auxiliary box displacement sensor signal is unreliable and invalid; then S540 is executed; S540. According to the determination results of S510 to S530, the following operations are performed:

[0063] If the gearbox shift displacement sensor signal is determined to be credible and valid, and the gearbox front auxiliary box displacement sensor signal is determined to be credible and valid, and the gearbox rear auxiliary box displacement sensor signal is determined to be credible and valid, then the gear position displacement sensor signal is determined to be credible and valid;

[0064] If the transmission shift displacement sensor signal is determined to be unreliable and invalid, and the transmission front auxiliary box displacement sensor signal is determined to be unreliable and invalid, and the transmission rear auxiliary box displacement sensor signal is determined to be unreliable and invalid, then the gear position displacement sensor signal is determined to be unreliable and invalid.

[0065] Preferably, the main box theoretical speed ratio is obtained according to the shift displacement in the gear position information of the gearbox;

[0066] The theoretical speed ratio of the front auxiliary box is obtained according to the displacement of the front auxiliary box in the gear position information of the gearbox;

[0067] The rear auxiliary box theoretical speed ratio is obtained according to the rear auxiliary box displacement in the gear position information of the gearbox;

[0068] The main gearbox theoretical-actual speed ratio deviation threshold is 10%;

[0069] The threshold value of the deviation between the theoretical and actual speed ratio of the front auxiliary gearbox is 10%;

[0070] The threshold value of the deviation between the theoretical and actual speed ratio of the rear auxiliary gearbox is 10%.

[0071] Compared with the prior art, the present invention has the following advantages:

[0072] 1. Since the principle of the present invention is to use the existing collected normal working condition data to indirectly calculate the verification and reference source of the displacement sensor reliability, there is no need to increase the monitoring circuit to fully load the functional safety requirements, and it will not increase the circuit logic complexity of the whole vehicle, nor increase the possibility of error in the vehicle-mounted electrical signal system, nor increase the resource consumption of computing devices such as ECU and EECU;

[0073] 2. Since the present invention does not need to add monitoring lines to fully meet functional safety requirements, the costs of the entire vehicle from design to manufacturing and subsequent maintenance are greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 A schematic diagram of the transmission operating mechanism controlling the movement of the shift fork shaft involved in the background technology description of the present invention;

[0075] Figure 2 The figure is a flow chart of the inspection method according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0076] The present invention is further explained below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0077] It should be noted in advance that this specific embodiment is implemented on a 12-speed AMT of our company, namely Dongfeng Commercial Vehicle Co., Ltd.; on the other hand, applying the present invention to other AMTs will also fall within the scope of protection of the present invention; on the other hand, this specific embodiment is used to support the practicality, novelty and creativity of the present invention, and should not be used as the final interpretation of the scope of the claims.

[0078] like Figure 2 As shown, a reliability test method for an AMT gear displacement sensor comprises the following steps:

[0079] S100. Obtain the current vehicle operation status; the vehicle operation status includes the vehicle stationary state, the state during the gear shifting process, and the vehicle running and the gear shifting completed state; then perform the following operations according to the vehicle operation status:

[0080] If the vehicle is in a stationary state or in a gear shifting state, the process returns to and executes S100 again.

[0081] If the vehicle operation state is the vehicle operation and the gear shifting is completed state, S200 is executed.

[0082] It should be noted that the function of S100 is to determine the operating status of the entire vehicle and eliminate the impact of the sensor's non-working state or normal fluctuations, such as when the vehicle is stationary or shifting gears.

[0083] S200. Obtain transmission gear position information, shaft speed information, and vehicle operating condition information from the gear displacement sensor.

[0084] It should be noted that the gear shift displacement, the front auxiliary box displacement, and the rear auxiliary box displacement can be directly read through the shaft displacement sensor.

[0085] In this specific embodiment, the gear position information of the transmission includes gear selection displacement, gear shifting displacement, front auxiliary gearbox displacement, and rear auxiliary gearbox displacement.

[0086] In this specific embodiment, the shaft speed information includes the gearbox intermediate shaft speed, the gearbox main shaft speed, the gearbox input shaft speed, and the gearbox output shaft speed.

[0087] It should be noted that the present invention can directly read the speed of the intermediate shaft of the gearbox through the intermediate shaft speed sensor.

[0088] It should be noted that the present invention can directly read the gearbox spindle speed through the spindle speed sensor.

[0089] It should be further explained that the present invention obtains the transmission input shaft speed and transmission output shaft speed through a shaft speed sensor; the reliability of the shaft speed sensor can be verified through other relevant speed sources of the vehicle, which is not within the scope of consideration of the technical solution of the present invention; when the technical solution of the present invention performs reliability verification of the gear displacement sensor, it is based on the premise that the shaft speed sensor is fault-free.

[0090] In this specific embodiment, the vehicle operating condition information includes vehicle speed, rear axle speed ratio, tire rolling radius, and engine speed information; and the engine speed information includes engine speed.

[0091] S300. According to the gear position information of the transmission, the current gear information is obtained; then, according to the current gear information and the gear position information of the transmission, the theoretical speed ratio is obtained;

[0092] It should be noted that, in the present invention, the gear position of the gearbox is determined by the gear position information of the gearbox, and then the theoretical speed ratio is obtained.

[0093] In this specific embodiment, the theoretical speed ratio includes the main box theoretical speed ratio, the front auxiliary box theoretical speed ratio, and the rear auxiliary box theoretical speed ratio.

[0094] In this specific embodiment, the main gear theoretical speed ratio is obtained according to the shift displacement in the gear position information of the transmission.

[0095] It should be noted that the actual gearbox main box shift fork position can be obtained from the shift displacement, and then it can be determined whether the gearbox main box is in 1st gear, 2nd gear, 3rd gear or R gear, so that the design gear ratio can be queried to obtain the main box theoretical speed ratio.

[0096] In this specific embodiment, the theoretical speed ratio of the front auxiliary box is obtained according to the displacement of the front auxiliary box in the gear position information of the transmission.

[0097] It should be noted that the displacement of the front auxiliary box can determine whether the front auxiliary box is in the high gear area or the low gear area, so that the design gear ratio can be queried to obtain the theoretical speed ratio of the front auxiliary box.

[0098] In this specific embodiment, the rear auxiliary box theoretical speed ratio is obtained according to the rear auxiliary box displacement in the gear position information of the transmission.

[0099] It should be noted that the displacement of the rear auxiliary box can determine whether the rear auxiliary box is in the high gear area or the low gear area, so that the design gear ratio can be queried to obtain the theoretical speed ratio of the rear auxiliary box.

[0100] S400. Calculate the actual speed ratio according to the shaft speed information;

[0101] In this specific embodiment, the actual speed ratio includes the intermediate shaft-main shaft actual speed ratio, the input shaft-intermediate shaft actual speed ratio, and the main shaft-output shaft actual speed ratio.

[0102] It should be noted that the present invention obtains the actual speed ratio of the intermediate shaft to the main shaft, the actual speed ratio of the input shaft to the intermediate shaft, and the actual speed ratio of the main shaft to the output shaft according to the speed of the intermediate shaft of the gearbox, the speed of the main shaft of the gearbox, the speed of the input shaft of the gearbox, and the speed of the output shaft of the gearbox; specifically:

[0103] In this specific embodiment, the actual speed ratio of the intermediate shaft to the main shaft is expressed as follows:

[0104]

[0105] Where: η4 is the actual speed ratio of the intermediate shaft to the main shaft; r mid is the gearbox intermediate shaft speed; r main is the gearbox main shaft speed.

[0106] In this specific embodiment, the actual speed ratio of the input shaft to the intermediate shaft is expressed as follows:

[0107]

[0108] Where: η5 is the actual speed ratio of input shaft to intermediate shaft; r input is the gearbox input shaft speed; the gearbox input shaft speed is expressed according to formula (3):

[0109] r input =r engine (3)

[0110] Where: r engine It is the engine speed in the engine speed information.

[0111] It should be noted that when the clutch is engaged, the transmission input shaft speed should be equal to the engine speed, and the transmission input shaft speed can be indirectly obtained through the engine speed information.

[0112] In this specific embodiment, the actual speed ratio of the main shaft to the output shaft is expressed as follows:

[0113]

[0114] Among them: η6 is the actual speed ratio of the main shaft to the output shaft; r output is the transmission output shaft speed; the transmission output shaft speed is calculated based on the vehicle speed, rear axle speed ratio, and tire rolling radius in the vehicle operating condition information.

[0115] It should be noted that the vehicle speed is read through the instrument speed and mileage sensor.

[0116] S500. Compare the theoretical speed ratio with the actual speed ratio, and perform the following operations based on the comparison result:

[0117] If the comparison result shows that the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is less than the manually preset speed ratio deviation threshold, the gear displacement sensor signal is determined to be credible and valid; then S700 is executed;

[0118] If the comparison result is that the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is greater than the speed ratio deviation threshold, the gear displacement sensor signal is determined to be unreliable and invalid; then S600 is executed.

[0119] It should be noted that S500 can be summarized as follows: If the actual speed ratio deviates greatly from the theoretical speed ratio, the gear displacement sensor signal is considered unreliable, and the displacement sensor signal needs to be processed to enter the fault response mechanism. If the deviation is within an acceptable range, the gear displacement sensor signal is considered valid and the sensor signal is used for strategy calculation.

[0120] In this specific embodiment, the speed ratio deviation includes the main gearbox theoretical-actual speed ratio deviation, the front auxiliary gearbox theoretical-actual speed ratio deviation, and the rear auxiliary gearbox theoretical-actual speed ratio deviation.

[0121] In this specific embodiment, the theoretical-actual speed ratio deviation of the main gearbox is expressed as follows:

[0122]

[0123] Among them: δ1 is the deviation between the theoretical and actual speed ratio of the main gearbox; η1 is the theoretical speed ratio of the main gearbox.

[0124] In this specific embodiment, the deviation between the theoretical and actual speed ratio of the front auxiliary box is expressed as follows:

[0125]

[0126] Among them: δ2 is the theoretical-actual speed ratio deviation of the front auxiliary box; η2 is the theoretical speed ratio of the front auxiliary box.

[0127] In this specific embodiment, the theoretical-actual speed ratio deviation of the rear auxiliary box is expressed as follows:

[0128]

[0129] Among them: δ3 is the theoretical-actual speed ratio deviation of the rear auxiliary box; η3 is the theoretical speed ratio of the rear auxiliary box.

[0130] In this specific embodiment, the speed ratio deviation threshold includes a main gearbox theoretical-actual speed ratio deviation threshold, a front auxiliary gearbox theoretical-actual speed ratio deviation threshold, and a rear auxiliary gearbox theoretical-actual speed ratio deviation threshold.

[0131] In this specific embodiment, the gear position displacement sensor signal includes a gearbox shift displacement sensor signal, a gearbox front auxiliary box displacement sensor signal, and a gearbox rear auxiliary box displacement sensor signal.

[0132] In this specific embodiment, the comparison between the theoretical speed ratio and the actual speed ratio in S500 specifically includes the following steps:

[0133] S510. Compare the theoretical-actual speed ratio deviation of the main gearbox with the theoretical-actual speed ratio deviation threshold of the main gearbox; then perform the following operations according to the comparison result:

[0134] If the main gearbox theoretical-actual speed ratio deviation is less than the main gearbox theoretical-actual speed ratio deviation threshold, it is determined that the transmission shift displacement sensor signal is credible and valid; then S520 is executed.

[0135] If the main gearbox theoretical-actual speed ratio deviation is greater than the main gearbox theoretical-actual speed ratio deviation threshold, it is determined that the transmission shift displacement sensor signal is unreliable and invalid; then S520 is executed.

[0136] In this specific embodiment, the threshold value of the deviation between the theoretical and actual speed ratio of the main gearbox is 10%.

[0137] It should be noted that the logic of S510 is that when the deviation between η1 and η4, namely δ1, exceeds 10%, the gearbox shift displacement sensor is considered unreliable, thereby completing the reliability verification of the gearbox shift displacement sensor.

[0138] S520. Compare the front auxiliary box theoretical-actual speed ratio deviation with the front auxiliary box theoretical-actual speed ratio deviation threshold; then perform the following operations according to the comparison result:

[0139] If the front auxiliary box theoretical-actual speed ratio deviation is less than the front auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission front auxiliary box displacement sensor signal is credible and valid; then S530 is executed.

[0140] If the front auxiliary box theoretical-actual speed ratio deviation is greater than the front auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission front auxiliary box displacement sensor signal is unreliable and invalid; then S530 is executed.

[0141] In this specific embodiment, the threshold value of the deviation between the theoretical and actual speed ratios of the front auxiliary gearbox is 10%.

[0142] It should be noted that the logic of S520 is that when the deviation between η2 and η5, namely δ2, exceeds 10%, the gearbox front auxiliary box displacement sensor is considered unreliable, thereby completing the reliability verification of the gearbox front auxiliary box displacement sensor.

[0143] S530. Compare the rear auxiliary box theoretical-actual speed ratio deviation with the rear auxiliary box theoretical-actual speed ratio deviation threshold; then perform the following operations according to the comparison result:

[0144] If the rear auxiliary box theoretical-actual speed ratio deviation is less than the rear auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission rear auxiliary box displacement sensor signal is credible and valid; then S540 is executed.

[0145] If the rear auxiliary box theoretical-actual speed ratio deviation is greater than the rear auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission rear auxiliary box displacement sensor signal is unreliable and invalid; then S540 is executed.

[0146] In this specific embodiment, the threshold value of the deviation between the theoretical and actual speed ratio of the rear auxiliary gearbox is 10%.

[0147] It should be noted that the logic of S530 is that when the deviation between η3 and η6, namely δ3, exceeds 10%, the gearbox rear auxiliary box displacement sensor is considered unreliable, thereby completing the reliability verification of the gearbox rear auxiliary box displacement sensor.

[0148] S540. According to the determination results of S510 to S530, perform the following operations:

[0149] If the transmission shift displacement sensor signal is determined to be credible and valid, and the transmission front auxiliary box displacement sensor signal is determined to be credible and valid, and the transmission rear auxiliary box displacement sensor signal is determined to be credible and valid, then the gear position displacement sensor signal is determined to be credible and valid.

[0150] If the transmission shift displacement sensor signal is determined to be unreliable and invalid, and the transmission front auxiliary box displacement sensor signal is determined to be unreliable and invalid, and the transmission rear auxiliary box displacement sensor signal is determined to be unreliable and invalid, then the gear position displacement sensor signal is determined to be unreliable and invalid.

[0151] It should be noted that the final logic of S500 is: if the actual speed ratio deviates greatly from the theoretical speed ratio, the gear displacement sensor signal is considered unreliable, and the displacement sensor signal needs to be processed to enter the fault response mechanism. If the deviation is within an acceptable range, the gear displacement sensor signal is considered valid and the sensor signal is used for strategy calculation.

[0152] S600. Enter the manually preset fault response mechanism; then execute S700.

[0153] S700. Exit this reliability test.

[0154] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0155] The disclosed embodiments are described above to enable any person skilled in the art to implement or use the present invention. Various modifications of these embodiments are obvious to those skilled in the art, and the general principles defined herein may also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0156] The above description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

[0157] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A reliability test method for an AMT gear displacement sensor, characterized in that: The following steps are involved: S100. Obtain the current vehicle operation state; the vehicle operation state includes the vehicle stationary state, the state during the gear shifting process, and the vehicle running and the gear shifting completed state; then perform the following operations according to the vehicle operation state: If the vehicle operation state is the vehicle stationary state or the state in the gear shifting process, return to and execute S100 again; If the vehicle operation state is the vehicle operation and gear shifting is completed state, execute S200; S200. Obtaining gearbox position information, shaft speed information, and vehicle operating condition information; S300. According to the gear position information of the transmission, the current gear information is obtained; then, according to the current gear information and the gear position information of the transmission, the theoretical speed ratio is obtained; S400. Calculate the actual speed ratio according to the shaft speed information; S500. Compare the theoretical speed ratio with the actual speed ratio, and perform the following operations according to the comparison result: If the comparison result is that the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is less than the manually preset speed ratio deviation threshold, it is determined that the gear displacement sensor signal is credible and valid; then S700 is executed; If the comparison result is that the speed ratio deviation between the theoretical speed ratio and the actual speed ratio is greater than the speed ratio deviation threshold, it is determined that the gear displacement sensor signal is unreliable and invalid; then S600 is executed; S600. Enter the manually preset fault response mechanism; then execute S700; S700. Exit this reliability test.

2. The reliability inspection method of the AMT gear displacement sensor according to claim 1 is characterized in that: The gearbox gear position information includes gear selection displacement, gear shift displacement, front auxiliary gearbox displacement, and rear auxiliary gearbox displacement; The shaft speed information includes the gearbox intermediate shaft speed, gearbox main shaft speed, gearbox input shaft speed, and gearbox output shaft speed; The theoretical speed ratio includes the main box theoretical speed ratio, the front auxiliary box theoretical speed ratio, and the rear auxiliary box theoretical speed ratio; The actual speed ratio includes the actual speed ratio of the intermediate shaft to the main shaft, the actual speed ratio of the input shaft to the intermediate shaft, and the actual speed ratio of the main shaft to the output shaft; The speed ratio deviation includes the main box theoretical-actual speed ratio deviation, the front auxiliary box theoretical-actual speed ratio deviation, and the rear auxiliary box theoretical-actual speed ratio deviation; The speed ratio deviation thresholds include a main gearbox theoretical-actual speed ratio deviation threshold, a front auxiliary gearbox theoretical-actual speed ratio deviation threshold, and a rear auxiliary gearbox theoretical-actual speed ratio deviation threshold; The vehicle operating condition information includes vehicle speed, rear axle speed ratio, tire rolling radius, and engine speed information; the engine speed information includes engine speed; The gear position displacement sensor signal includes a gearbox shift displacement sensor signal, a gearbox front auxiliary box displacement sensor signal, and a gearbox rear auxiliary box displacement sensor signal.

3. The reliability inspection method of the AMT gear displacement sensor according to claim 2 is characterized in that: The actual speed ratio of the intermediate shaft to the main shaft is expressed as follows: Where: η4 is the actual speed ratio of the intermediate shaft to the main shaft; r mid is the gearbox intermediate shaft speed; r main is the gearbox main shaft speed.

4. The reliability inspection method of the AMT gear displacement sensor according to claim 3 is characterized in that: The actual speed ratio of the input shaft to the intermediate shaft is expressed as follows: Where: η5 is the actual speed ratio of the input shaft to the intermediate shaft; r input is the gearbox input shaft speed; the gearbox input shaft speed is expressed as follows: r input ＝r engine Where: r engine is the engine speed in the engine speed information.

5. The reliability inspection method of the AMT gear displacement sensor according to claim 4 is characterized in that: The actual speed ratio of the main shaft to the output shaft is expressed as follows: Where: η6 is the actual speed ratio of the main shaft to the output shaft; r output is the transmission output shaft speed; the transmission output shaft speed is calculated based on the vehicle speed, the rear axle speed ratio, and the tire rolling radius in the vehicle operating condition information.

6. The reliability inspection method of the AMT gear displacement sensor according to claim 5 is characterized in that: The main box theoretical-actual speed ratio deviation is expressed as follows: Wherein: δ1 is the theoretical-actual speed ratio deviation of the main box; η1 is the theoretical speed ratio of the main box.

7. The reliability inspection method of the AMT gear displacement sensor according to claim 6, characterized in that: The theoretical-actual speed ratio deviation of the front auxiliary box is expressed as follows: Wherein: δ2 is the deviation between the theoretical and actual speed ratio of the front auxiliary box; η2 is the theoretical speed ratio of the front auxiliary box.

8. The reliability inspection method of the AMT gear displacement sensor according to claim 7, characterized in that: The theoretical-actual speed ratio deviation of the rear auxiliary box is expressed as follows: Wherein: δ3 is the theoretical-actual speed ratio deviation of the rear auxiliary box; η3 is the theoretical speed ratio of the rear auxiliary box.

9. The reliability inspection method of the AMT gear displacement sensor according to claim 8, characterized in that: S500 compares the theoretical speed ratio with the actual speed ratio, which specifically includes the following steps: S510. Compare the main box theoretical-actual speed ratio deviation with the main box theoretical-actual speed ratio deviation threshold; then perform the following operations according to the comparison result: If the master box theoretical-actual speed ratio deviation is less than the master box theoretical-actual speed ratio deviation threshold, it is determined that the gearbox shift displacement sensor signal is credible and valid; then S520 is executed; If the master box theoretical-actual speed ratio deviation is greater than the master box theoretical-actual speed ratio deviation threshold, it is determined that the gearbox shift displacement sensor signal is unreliable and invalid; then S520 is executed; S520. Compare the front auxiliary box theoretical-actual speed ratio deviation with the front auxiliary box theoretical-actual speed ratio deviation threshold; then perform the following operations according to the comparison result: If the front auxiliary box theoretical-actual speed ratio deviation is less than the front auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission front auxiliary box displacement sensor signal is credible and valid; then S530 is executed; If the front auxiliary box theoretical-actual speed ratio deviation is greater than the front auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission front auxiliary box displacement sensor signal is unreliable and invalid; then S530 is executed; S530. Compare the rear auxiliary box theoretical-actual speed ratio deviation with the rear auxiliary box theoretical-actual speed ratio deviation threshold; and then perform the following operations according to the comparison result: If the rear auxiliary box theoretical-actual speed ratio deviation is less than the rear auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission rear auxiliary box displacement sensor signal is credible and valid; then S540 is executed; If the rear auxiliary box theoretical-actual speed ratio deviation is greater than the rear auxiliary box theoretical-actual speed ratio deviation threshold, it is determined that the transmission rear auxiliary box displacement sensor signal is unreliable and invalid; then S540 is executed; S540. According to the determination results of S510 to S530, perform the following operations: If the gearbox shift displacement sensor signal is determined to be credible and valid, and the gearbox front auxiliary box displacement sensor signal is determined to be credible and valid, and the gearbox rear auxiliary box displacement sensor signal is determined to be credible and valid, then the gear position displacement sensor signal is determined to be credible and valid; If the transmission shift displacement sensor signal is determined to be unreliable and invalid, and the transmission front auxiliary box displacement sensor signal is determined to be unreliable and invalid, and the transmission rear auxiliary box displacement sensor signal is determined to be unreliable and invalid, then the gear position displacement sensor signal is determined to be unreliable and invalid.

10. The reliability inspection method of the AMT gear displacement sensor according to claim 9, characterized in that: The main gearbox theoretical speed ratio is obtained according to the shift displacement in the gearbox gear position information; The theoretical speed ratio of the front auxiliary box is obtained according to the displacement of the front auxiliary box in the gear position information of the gearbox; The rear auxiliary box theoretical speed ratio is obtained according to the rear auxiliary box displacement in the gear position information of the gearbox; The main gearbox theoretical-actual speed ratio deviation threshold is 10%; The threshold value of the deviation between the theoretical and actual speed ratio of the front auxiliary gearbox is 10%; The threshold value of the deviation between the theoretical and actual speed ratio of the rear auxiliary gearbox is 10%.

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