Gear engaging test method with speed difference and related device

Abstract

The invention discloses a belt speed difference gear engaging test method and a related device, a belt speed difference gear engaging test system comprises a rack control system, a transmission control unit, an upper computer, a rack base, a transmission, a fixing device and an output motor, the fixing device fixes the transmission on the rack base, and an output shaft of the transmission is connected with the output motor. And after acquiring the target speed difference and the target gear, the upper computer determines the target rotating speed of the output shaft of the transmission according to the target speed difference and sends the target rotating speed to the rack control system, so that the rack control system controls the rotating speed of the output shaft of the transmission through the output motor. And the upper computer sends the target gear to a transmission control unit, so that when the rack control system controls the rotating speed of the output shaft of the transmission to reach the target rotating speed through the output motor, the gear of a shifting fork assembly in the transmission is driven to be changed into the target gear. Automatic testing is achieved through the rack testing system, the requirement for a testing site is lowered, the testing period is shortened, and the testing safety is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and in particular, to a speed difference shifting test method and related device. Background Art

[0002] The shift fork assembly is an important part of a dual clutch transmission (DCT). When the transmission control unit issues a shifting command, the transmission control unit (TCU) controls the movement of the synchronizer through the shift fork in the shift fork assembly to achieve gear engagement and disengagement. In the calibration development of the transmission control unit, it is necessary to verify vehicle starting, shifting and other working conditions, and optimize the strategy or calibration according to the specific performance. Different working conditions at the vehicle level are decomposed to the shift fork control level, which can be equivalent to the shift forks of different gears engaging at different speed differences (i.e., the difference between the target gear speed and the intermediate shaft speed), so as to verify the vehicle performance according to the shift fork control effect at different speed differences.

[0003] In the related art, generally, a speed difference shifting method based on a real vehicle environment is adopted. Specifically, the test personnel drive the test vehicle according to certain test specifications, so as to verify the performance of the test vehicle under various working conditions, and the test results are directly perceived by the test personnel.

[0004] However, the above method has high requirements for the test site, a long test cycle, and certain risks for some high-speed working conditions. Summary of the Invention

[0005] In view of the above problems, the present application provides a speed difference shifting test method and related device, which realize automatic testing through a bench test system, reduce the requirements for the test site, shorten the test cycle, and improve the safety of the test.

[0006] Based on this, the embodiments of the present application disclose the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides a speed difference shifting test method, which is applied to a speed difference shifting test system. The speed difference shifting test system includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor. The fixing device fixes the transmission on the bench base, and the output shaft of the transmission is connected to the output motor. The method includes:

[0008] The host computer obtains a target speed difference and a target gear;

[0009] The host computer determines the target speed of the output shaft of the transmission according to the target speed difference;

[0010] The host computer sends the target rotational speed to the bench control system and sends the target gear position to the transmission control unit;

[0011] When the rotational speed of the output shaft of the transmission controlled by the bench control system through the output motor reaches the target rotational speed, the transmission control unit drives the gear position of the shift fork assembly in the transmission to become the target gear position.

[0012] Optionally, the method for determining the target speed difference is as follows:

[0013] The host computer determines the theoretical speed difference required for the first working condition according to the shift diagram;

[0014] The host computer acquires the measured speed difference required for the second working condition;

[0015] The host computer takes the theoretical speed difference and the measured speed difference as the target speed difference respectively.

[0016] Optionally, the method further includes:

[0017] The host computer determines multiple pending preselected gear positions for one target gear position;

[0018] The host computer determines the required output shaft rotational speeds corresponding to the multiple pending preselected gear positions according to the target gear position, the target speed difference, and the multiple pending preselected gear positions;

[0019] The host computer determines the preselected gear position from the multiple pending preselected gear positions according to the multiple required output shaft rotational speeds;

[0020] The host computer determines the target rotational speed of the output shaft of the transmission according to the target speed difference, including:

[0021] The host computer determines the target rotational speed of the output shaft of the transmission according to the target speed difference and the preselected gear position;

[0022] When the rotational speed of the output shaft of the transmission controlled by the bench control system through the output motor reaches the target rotational speed, the transmission control unit drives the gear position of the shift fork assembly in the transmission to become the target gear position, including:

[0023] When the rotational speed of the output shaft of the transmission controlled by the bench control system through the output motor reaches the target rotational speed, the transmission control unit drives the gear position of the shift fork assembly in the transmission to first become the preselected gear position and then become the target gear position.

[0024] Optionally, the host computer determines the preselected gear position from the multiple pending preselected gear positions according to the multiple required output shaft rotational speeds, including:

[0025] The host computer determines a preselected gear from the multiple to-be-selected preselected gears according to the similarity of the rotational speeds of the multiple output shafts corresponding to the requirements.

[0026] Optionally, the transmission control unit drives the gear of the shift fork assembly in the transmission to first become the preselected gear and then become the target gear, including:

[0027] The transmission control unit drives the gear of the shift fork assembly in the transmission to first become the preselected gear. After the preselected gear is successfully engaged, a command to disengage the preselected gear is issued, and after a first preset time from issuing the command to disengage the preselected gear, it becomes the target gear.

[0028] Optionally, the method further includes:

[0029] The host computer obtains multiple speed differences to be adjusted, uses the multiple speed differences to be adjusted as the target speed differences respectively, executes the method described in the first aspect, and the execution interval is a second preset time.

[0030] Optionally, the method further includes:

[0031] The host computer obtains multiple speed differences to be adjusted, uses the multiple speed differences to be adjusted as the target speed differences respectively, and executes the method described in the first aspect multiple times.

[0032] In a second aspect, the present application provides a speed-difference shift test system. The speed-difference shift test system includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor;

[0033] The host computer is configured to obtain a target speed difference and a target gear, determine a target rotational speed of the output shaft of the transmission according to the target speed difference, send the target rotational speed to the bench control system, and send the target gear to the transmission control unit;

[0034] The bench control system is configured to control the rotational speed of the output shaft of the transmission to reach the target rotational speed through the output motor; wherein, the output shaft of the transmission is connected to the output motor;

[0035] The transmission control unit is configured to drive the gear of the shift fork assembly in the transmission to become the target gear.

[0036] The fixing device is configured to fix the transmission to the bench base.

[0037] Optionally, the host computer is further configured to:

[0038] Determine a theoretical speed difference required for a first working condition according to a shift diagram;

[0039] Collect the measured speed difference required for the second working condition;

[0040] Use the theoretical speed difference and the measured speed difference as the target speed difference respectively.

[0041] Optionally, the host computer is further configured to:

[0042] Determine multiple pending pre-engaged gears for one of the target gears;

[0043] The host computer determines the required output shaft speeds corresponding to the multiple pending pre-engaged gears according to the target gear, the target speed difference, and the multiple pending pre-engaged gears;

[0044] The host computer determines the pre-engaged gear from the multiple pending pre-engaged gears according to the multiple required output shaft speeds;

[0045] The host computer is specifically configured to:

[0046] The host computer determines the target speed of the output shaft of the transmission according to the target speed difference and the pre-engaged gear;

[0047] The transmission control unit is specifically configured to:

[0048] When the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, the transmission control unit drives the gear of the shift fork assembly in the transmission to first change to the pre-engaged gear and then to the target gear.

[0049] Optionally, the host computer is specifically configured to:

[0050] The host computer determines the pre-engaged gear from the multiple pending pre-engaged gears according to the similarity of the multiple required output shaft speeds.

[0051] Optionally, the transmission control unit is specifically configured to:

[0052] The transmission control unit drives the gear of the shift fork assembly in the transmission to first change to the pre-engaged gear. After the pre-engaged gear is successfully engaged, a pre-engaged gear disengagement command is issued, and the gear changes to the target gear after a first preset time from the issuance of the pre-engaged gear disengagement command.

[0053] Optionally, the host computer is further configured to:

[0054] Obtain multiple speed differences to be adjusted, use the multiple speed differences to be adjusted as the target speed differences respectively, execute the method described in the first aspect, and the execution interval is a second preset time.

[0055] Optionally, the host computer is further configured to:

[0056] The host computer obtains a plurality of speed differences to be adjusted, respectively uses the plurality of speed differences to be adjusted as the target speed differences, and executes the method described in the first aspect.

[0057] In a third aspect, the present application provides a computer device, which includes a processor and a memory:

[0058] The memory is used to store program codes and transmit the program codes to the processor;

[0059] The processor is configured to execute the method described in the above aspect according to the instructions in the program codes.

[0060] In a fourth aspect, the present application provides a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the method described in the above aspect.

[0061] On the other hand, an embodiment of the present application provides a computer program product or a computer program, which includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method described in the above aspect.

[0062] The advantages of the above technical solutions of the present application are as follows:

[0063] In a belt speed difference shifting test system, it includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor. Among them, the fixing device fixes the transmission to the bench base, and the output shaft of the transmission is connected to the output motor. After the host computer obtains the target speed difference and the target gear, it determines the target speed of the output shaft of the transmission according to the target speed difference, and sends the target speed to the bench control system, so that the bench control system controls the speed of the output shaft of the transmission through the output motor. The host computer sends the target gear to the transmission control unit, so that when the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, it drives the gear of the fork assembly in the transmission to become the target gear. Thus, automatic testing is realized through the bench test system, the requirements for the test site are reduced, the test cycle is shortened, and the safety of the test is improved. Description of the Drawings

[0064] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0065] Figure 1 Schematic diagram of a speed-difference shifting test system provided by the present application;

[0066] Figure 2 Flowchart of a speed-difference shifting test method provided by an embodiment of the present application;

[0067] Figure 3 Schematic diagram of a test result provided by an embodiment of the present application;

[0068] Figure 4 Structural diagram of a computer device provided by an embodiment of the present application. Detailed implementation manners

[0069] To enable those skilled in the art to better understand the solutions of the present application, the following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0070] A speed-difference shifting test method provided by an embodiment of the present application is applied to a speed-difference shifting test system. The speed-difference shifting test system includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor. Among them, the fixing device fixes the transmission to the bench base, and the output shaft of the transmission is connected to the output motor.

[0071] As a possible implementation manner, the following will be combined with Figure 1 , to illustrate the speed-difference shifting test system provided by an embodiment of the present application. In the following Figure 1 , component 1 is the bench control system, component 2 is the transmission control unit, component 3 is the host computer, component 4 is the input motor, component 5 is the bench base, component 6 is the transmission, component 7 is the tooling, component 8 is the tooling base, and component 9 is the output motor. Component 7 and component 8 form the fixing device.

[0072] It should be noted that the transmission body is installed on the test bench through tooling and a tooling base. The input shaft of the transmission is connected to the input motor, the output shaft of the transmission is connected to the output motor, and the transmission control unit is connected to the bench control system and the host computer. Programs such as calibration tool software and fork automatic gear shifting programs are running in the host computer. Among them, the calibration tool software is the software for controlling the speed difference and gear position, so as to verify the performance of the vehicle according to the control effect of the fork at different speed differences; the fork automatic gear shifting program is developed based on the calibration tool software, so that the fork automatic gear shifting program can reuse the interfaces of the calibration tool software, etc.

[0073] Next, in combination with Figure 2 , a speed-difference gear shifting test method provided by an embodiment of the present application will be introduced. Refer to Figure 2 . This figure is a flowchart of a speed-difference gear shifting test method provided by an embodiment of the present application. The method may include S201 - S204.

[0074] S201: The host computer obtains the target speed difference and the target gear position.

[0075] The speed difference is the difference between the gear on the countershaft corresponding to the target gear position and the countershaft speed during the gear shifting process. As can be seen from the foregoing, it is possible to verify the performance of the vehicle by shifting gears for different gear forks at different speed differences and according to the control effect of the fork at different speed differences. The target speed difference is the speed difference corresponding to the gear shifting of the target gear fork.

[0076] It should be noted that the target speed difference and the target gear position can be determined according to the test requirements. The test requirements refer to the working conditions to be measured. The target speed difference and the target gear position equivalent to the working conditions to be measured are determined according to the test requirements, so as to verify the performance under different working conditions. Taking the high and low temperature dynamic gear shifting test of a 7-speed dual-clutch automatic transmission as an example, each gear needs to be shifted at a sufficiently large speed difference. The target speed differences for each gear are shown in Table 1.

[0077] Table 1 Corresponding relationship between each gear and speed difference

[0078] Gear position / i 1 2 3 4 5 6 7 Speed difference / rpm 300 1200 1200 2000 3000 4000 2800

[0079] For example, when the target gear position is the 2nd gear, the target speed difference can be 1200.

[0080] S202: The host computer determines the target speed of the output shaft of the transmission according to the target speed difference.

[0081] In order to detect whether the transmission reaches the target speed difference, the target speed difference can be converted into a speed that is easier to detect, that is, the target speed of the output shaft of the transmission is determined according to the target speed difference.

[0082] As a possible implementation, determining the target speed of the output shaft of the transmission according to the target speed difference can refer to formula (1):

[0083] Dn 0 = i 目标档位主减速比 × N out (1)

[0084] Where Dn_0 is the target speed difference, i 目标档位主减速比 is the main reduction ratio of the target gear, and N out is the target speed of the output shaft of the transmission.

[0085] S203: The host computer sends the target speed to the bench control system and sends the target gear to the transmission control unit.

[0086] Among them, the bench control system can control the rotation of the output motor, and the output motor drives the rotation of the output shaft of the transmission connected to it, so that the bench control system realizes the speed control of the output shaft of the transmission. The transmission control unit is used to control the gear of the shift fork assembly in the transmission. Therefore, the host computer sends the target speed to the bench control system and sends the target gear to the transmission control unit.

[0087] S204: When the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, the transmission control unit drives the gear of the shift fork assembly in the transmission to become the target gear.

[0088] After receiving the target speed, the bench control system controls the output motor according to the target speed and then controls the speed of the output shaft of the transmission. When the speed of the output shaft of the transmission reaches the target speed, the transmission control unit drives the gear of the shift fork assembly in the transmission to become the target gear, so as to realize gear shifting with a sufficiently large speed difference and obtain the test result.

[0089] For example, after detecting that the speed of the output shaft of the transmission reaches the target speed, the gear shifting instruction is sent from the host computer to the transmission control unit by calling the secondary development API of the calibration tool, and then the shift fork is driven to perform the corresponding gear shifting action.

[0090] As can be seen from the above technical solution, in the speed difference shifting test system, it includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor. Among them, the fixing device fixes the transmission to the bench base, and the output shaft of the transmission is connected to the output motor. After obtaining the target speed difference and the target gear position, the host computer determines the target speed of the output shaft of the transmission according to the target speed difference, and sends the target speed to the bench control system, so that the bench control system controls the speed of the output shaft of the transmission through the output motor. The host computer sends the target gear position to the transmission control unit, so that when the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, the gear position of the fork assembly in the transmission is driven to become the target gear position. Thus, automatic testing is realized through the bench test system, the requirements for the test site are reduced, the test cycle is shortened, and the safety of the test is improved.

[0091] As a possible implementation, the host computer can determine the theoretical speed difference required for the first working condition according to the shift diagram, and then collect the measured speed difference required for the second working condition, and use the theoretical speed difference and the measured speed difference as the target speed difference respectively. Among them, the shift diagram is a schematic diagram with the vehicle speed on the x-axis and the throttle on the y-axis. Through the shift diagram, the theoretical speed difference required under general working conditions can be determined, that is, the first working condition is a general working condition including multiple working conditions that can be determined from the shift diagram. However, in actual applications, some special working conditions cannot be obtained through the shift diagram. Therefore, through actual measurement, the measured speed difference of some special working conditions including at least one working condition that cannot be determined from the shift diagram, that is, the second working condition, can be collected. Thus, the coverage of the speed difference in this test can be expanded through the measured speed difference and the theoretical speed difference.

[0092] After research, it is found that there are two shifting situations in actual working conditions: ① coaxial non-gear shifting; ② coaxial gear shifting. Due to the change of the transmission system speed ratio in both situations, the speed difference is relatively large under the same vehicle speed and target gear position. ① Coaxial non-gear shifting can refer to the aforementioned formula (1), and ② coaxial gear shifting can refer to formula (2):

[0093]

[0094] Among them, Dn_1 is the target speed difference, N out is the target speed, i 目标档位速比 is the target gear ratio, i 同轴在档档位速比 is the coaxial in-gear ratio, i 不带主减的目标档位速比 is the target gear ratio without the main reducer.

[0095] Although it is possible to achieve the required speed difference by only adjusting the rotational speed of the output shaft of the transmission through the method of formula (1), and the test case design is simple and fast, under the action of the oil shear effect (Drag), the input shaft of the transmission will still rotate, resulting in an uncontrollable actual speed difference. As a result, it is impossible to accurately control the output shaft of the transmission to reach the target rotational speed through the bench control system, which in turn affects the subsequent test results. In addition, after shifting into a gear, it is necessary to wait for 2 seconds before proceeding, and the waiting time for the speed difference to recover is relatively long, resulting in a long test time. Based on this, in the embodiments of the present application, through the method of formula (2), the construction of the speed difference for each gear is achieved by pre-shifting into a non-target gear in combination with the adjustment of the output shaft rotational speed, which will be specifically described below with reference to A1 - A5.

[0096] A1: The host computer determines multiple pending pre-shift gears for a target gear.

[0097] The pre-shift gear is the gear shifted before shifting into the target gear, that is, after shifting into the pre-shift gear, the target gear is shifted, thereby reducing the gap in the actual speed difference caused by directly shifting into the target gear. The pending pre-shift gear is the gear that has not been determined as the pre-shift gear.

[0098] A2: The host computer determines the required output shaft rotational speeds corresponding to the multiple pending pre-shift gears according to the target gear, the target speed difference, and the multiple pending pre-shift gears.

[0099] As a possible implementation manner, in order to avoid the excessive speed difference from affecting the durability of components such as the synchronizer, boundary conditions for the pending pre-shift gears can be set. The boundary conditions for the pending pre-shift gears are as follows:

[0100] (1) The speed difference of the pending pre-shift gear cannot be too large, and the limit is set around 4000 rpm.

[0101] (2) The rotational speed of the input shaft after shifting into the pending pre-shift gear cannot be too high, and the limit is set around 6000 rpm.

[0102] (3) The rotational speed of the input shaft after shifting into the target gear cannot be too high, and the limit is set around 6000 rpm.

[0103] (4) The required output shaft rotational speed during pre-shifting cannot exceed the upper limit of 1000 rpm provided by the bench output motor.

[0104] Thus, the pending pre-shift gears can be determined for each gear through the boundary conditions. Continuing with the example of the high and low temperature dynamic gear shifting test of a 7-speed dual clutch automatic transmission, Table 2 shows the calculation results of the 3 pending pre-shift gears corresponding to each gear under the boundary conditions.

[0105] Table 2 Multiple pending pre-shift gears

[0106]

[0107]

[0108] Among them, the rotational speed of the demand output shaft, the pre-hanging speed difference, the rotational speed of the pre-hanging input shaft, and the rotational speed of the target gear input shaft can all be determined by the target gear, the target speed difference, and the undetermined pre-hanging gear. Through boundary conditions, 4 shifting sequence combinations of 6-4 (undetermined pre-hanging gear is 6, target gear is 4), 7-5 (undetermined pre-hanging gear is 7, target gear is 5), 4-6 (undetermined pre-hanging gear is 4, target gear is 6), and 5-7 (undetermined pre-hanging gear is 5, target gear is 7) can be excluded.

[0109] A3: The host computer determines the pre-hanging gear from multiple undetermined pre-hanging gears according to multiple rotational speeds of the demand output shaft.

[0110] As a possible implementation, the host computer determines the pre-hanging gear from multiple undetermined pre-hanging gears according to the similarity of multiple rotational speeds of the demand output shaft. For example, as can be seen from Table 2, the rotational speeds of the demand output shaft of 5 shifting sequence combinations such as 6-2 (undetermined pre-hanging gear is 6, target gear is 2), 7-3 (undetermined pre-hanging gear is 7, target gear is 3), 2-4 (undetermined pre-hanging gear is 2, target gear is 4), 2-6 (undetermined pre-hanging gear is 2, target gear is 6), and 3-7 (undetermined pre-hanging gear is 3, target gear is 7) are relatively close, and the overall distribution is between 340 and 390 rpm. That is, there is similarity among these 5 shifting sequence combinations, and these 5 undetermined pre-hanging gears can be used as the pre-hanging gears corresponding to the target gears.

[0111] A4: The host computer determines the target rotational speed of the output shaft of the transmission according to the target speed difference and the pre-hanging gear.

[0112] Continuing with Table 2 as an example, considering the speed difference loss due to oil drag and the verification efficiency during the process of shifting from the pre-hanging gear to the target gear to start eliminating the speed difference, the rotational speed of the demand output shaft of the above gears is set to 400 rpm, and the shifting sequence of each gear is finally shown in Table 3.

[0113] Table 3 Shifting Sequences Corresponding to Each Gear

[0114]

[0115] For example, when the target gear is 1, the corresponding pre-hanging gear is 5. Another example is that when the target gear is 6, the corresponding pre-hanging gear is 2. Thus, when the target rotational speed is 400, 5 working conditions can be run, thereby eliminating the need to adjust the rotational speed of the output shaft, shortening the test time, improving the test efficiency, and also extending the service life of the output motor.

[0116] A5: When the bench control system reaches the target speed by controlling the speed of the output shaft of the transmission through the output motor, the transmission control unit drives the shift fork assembly in the transmission to first change to the preselected gear and then to the target gear.

[0117] For example, after determining the gear shifting sequence of each gear, the corresponding output shaft speed curve is input into the bench control system, and the shift fork automatic gear shifting program is run, allowing the tester to finely adjust the speed difference according to the actual situation, and finally obtaining the single test result as Figure 3 shown. In Figure 3 , the positions of the shift forks are respectively shown when the target speeds are 50, 90, 200, and 400.

[0118] In the related art, a speed-difference gear shifting method based on the bench environment is also used for testing. This method realizes speed-difference gear shifting to the target gear by controlling the input and output shaft motor speeds and gear shifting of the bench. Among them, the motor speed curve is input into the bench control system in tabular form (i.e., the target speed is sent to the bench control system), and the gear shifting is designed in the bench control system (the target gear is sent to the bench control system). The test result has good coverage of the speed difference, high repeatability, and a short test cycle, but the test case writing cycle is long, and it is necessary to manually select the input combination of the target gear and the target speed, and the portability for similar working condition tests is poor.

[0119] Compared with the related art, by testing in the manner of A1 - A5, only the target speed, the preselected gear, and the target gear need to be adjusted, without creating a test case for each combination, with higher reusability, shorter test time, and higher test efficiency.

[0120] As a possible implementation, the transmission control unit drives the shift fork assembly in the transmission to first change to the preselected gear. After the preselected gear is successfully shifted, a preselected gear shift-out command is issued, and then it changes to the target gear after the first preset time from the issuance of the preselected gear shift-out command. The first preset time is the interval time between the preselected gear and the target gear, that is, the shift-out and shift-in time interval is the time interval between the preselected gear shift-out command and the target gear shift-in command. As the first preset time becomes shorter, the transmission generates more heat. As the first preset time becomes longer, the accuracy of controlling the speed difference becomes lower. As a possible implementation, the first preset time can be 0.4 seconds.

[0121] As a possible implementation, obtain multiple speed differences to be adjusted, use the multiple speed differences to be adjusted as target speed differences respectively, execute the method described in S201 - S204, and the execution interval is the second preset time. Thus, after each adjustment of the target speed difference, the second preset time can be interposed, that is, the second preset time is the time interval between two tests. As the second preset time becomes shorter, the heat generation of the transmission is greater; as the second preset time becomes longer, the test cycle is longer. As a possible implementation, the second preset time can be 30 seconds.

[0122] As a possible implementation, obtain multiple speed differences to be adjusted, use the multiple speed differences to be adjusted as target speed differences respectively, and execute the method described in S201 - S204 multiple times. Thus, for a test case, multiple tests are performed, that is, the output shaft speed curve is executed in multiple cycles, which can improve the accuracy of the test.

[0123] For the convenience of understanding, the following uses an embodiment to illustrate the speed - difference shifting test method provided by the embodiments of the present application.

[0124] (1) First, weld the differential of the transmission to be tested and install the transmission on the verification bench.

[0125] (2) Connect the transmission control unit to the bench control system and the upper computer calibration tool, and configure the corresponding IP addresses according to the communication protocols between the control unit, the bench control system, and the upper computer calibration tool.

[0126] (3) The upper computer determines multiple pending pre - shifting gears for a target gear; the upper computer determines the required output shaft speeds corresponding to the multiple pending pre - shifting gears according to the target gear, the target speed difference, and the multiple pending pre - shifting gears; the upper computer determines the pre - shifting gear from the multiple pending pre - shifting gears according to the multiple required output shaft speeds to obtain the shifting timing sequence. The upper computer determines the target speed of the output shaft of the transmission according to the target speed difference and the pre - shifting gear, and writes the shifting timing sequence into the fork automatic shifting program of the upper computer.

[0127] (4) Determine the output shaft motor speed curve according to the target speed and input the output shaft motor speed curve into the bench control system.

[0128] (5) After determining that the communication between the upper computer calibration tool and the control unit is normal, run the fork automatic shifting program, start the output shaft motor, and the automatic shifting program detects the output shaft speed. When the target speed is reached, the corresponding shifting timing sequence is sent to the control unit to drive the fork to perform the reverse - shifting action.

[0129] (6) When the traversal of the target speed is completed, the shifting test ends.

[0130] Thus, the verification process is automated, and the verification efficiency is significantly improved. The gear shifting sequence is implemented based on code, with high flexibility and good portability for different verification working conditions.

[0131] In addition to the belt speed difference gear shifting test method provided by the embodiments of the present application, a belt speed difference gear shifting test system is also provided. As Figure 1 shown, the belt speed difference gear shifting test system includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor.

[0132] The host computer is configured to obtain a target speed difference and a target gear position, determine a target speed of the output shaft of the transmission according to the target speed difference, send the target speed to the bench control system, and send the target gear position to the transmission control unit.

[0133] The bench control system is configured to control the speed of the output shaft of the transmission to reach the target speed through the output motor; wherein, the output shaft of the transmission is connected to the output motor.

[0134] The transmission control unit is configured to drive the gear position of the shift fork assembly in the transmission to become the target gear position.

[0135] As a possible implementation, the host computer is further configured to:

[0136] Determine the theoretical speed difference required for the first working condition according to the shift diagram;

[0137] Collect the measured speed difference required for the second working condition;

[0138] Respectively use the theoretical speed difference and the measured speed difference as the target speed difference.

[0139] As a possible implementation, the host computer is further configured to:

[0140] Determine multiple pending pre-shift gear positions for one target gear position;

[0141] The host computer determines the required output shaft speeds respectively corresponding to the multiple pending pre-shift gear positions according to the target gear position, the target speed difference, and the multiple pending pre-shift gear positions;

[0142] The host computer determines the pre-shift gear position from the multiple pending pre-shift gear positions according to the multiple required output shaft speeds;

[0143] Specifically, the host computer is configured to:

[0144] The host computer determines the target speed of the output shaft of the transmission according to the target speed difference and the pre-shift gear position;

[0145] The transmission control unit is specifically configured to:

[0146] When the bench control system controls the rotational speed of the output shaft of the transmission to reach the target rotational speed through the output motor, the transmission control unit drives the gear position of the fork assembly in the transmission to first change to the preselected gear position and then change to the target gear position.

[0147] As a possible implementation, the host computer is specifically configured to:

[0148] The host computer determines the preselected gear position from the multiple pending preselected gear positions according to the similarity of the rotational speeds of the multiple required output shafts.

[0149] As a possible implementation, the transmission control unit is specifically configured to:

[0150] The transmission control unit drives the gear position of the fork assembly in the transmission to first change to the preselected gear position. After the preselected gear position is successfully engaged, a command to disengage the preselected gear position is issued, and after a first preset time interval from the issuance of the command to disengage the preselected gear position, it changes to the target gear position.

[0151] As a possible implementation, the host computer is further configured to:

[0152] Obtain multiple speed differences to be adjusted, respectively use the multiple speed differences to be adjusted as the target speed differences, execute the method described in S201 - S204, and the execution interval is a second preset time.

[0153] As a possible implementation, the host computer is further configured to:

[0154] Obtain multiple speed differences to be adjusted, respectively use the multiple speed differences to be adjusted as the target speed differences, and execute the method described in S201 - S204 multiple times.

[0155] As can be seen from the above technical solutions, in the speed - difference shifting test system, it includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor. Among them, the fixing device is fixed to the bench base, and the output shaft of the transmission is connected to the output motor. After the host computer obtains the target speed difference and the target gear position, it determines the target rotational speed of the output shaft of the transmission according to the target speed difference and sends the target rotational speed to the bench control system, so that the bench control system controls the rotational speed of the output shaft of the transmission through the output motor. The host computer sends the target gear position to the transmission control unit, so that when the bench control system controls the rotational speed of the output shaft of the transmission to reach the target rotational speed, it drives the gear position of the fork assembly in the transmission to change to the target gear position. Thus, through the bench test system, automatic testing is realized, the requirements for the test site are reduced, the test cycle is shortened, and the test safety is improved.

[0156] The embodiments of the present application also provide a computer device. Refer to Figure 4 , which shows the structural diagram of a computer device provided by the embodiments of the present application. As Figure 4 shown, the device includes a processor 410 and a memory 420:

[0157] The memory 410 is used to store program codes and transmit the program codes to the processor;

[0158] The processor 420 is used to execute any one of the belt speed difference gear shifting test methods provided in the above embodiments according to the instructions in the program codes.

[0159] The embodiments of the present application provide a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute any one of the belt speed difference gear shifting test methods provided in the above embodiments.

[0160] The embodiments of the present application also provide a computer program product or a computer program. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the belt speed difference gear shifting test method provided in various optional implementation manners of the above aspects.

[0161] It should be noted that the embodiments in this specification are described in a progressive manner. The key point of each embodiment is the difference from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the systems or devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0162] It should be understood that in the present application, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally means that the associated objects before and after are in an "or" relationship. "At least one (one) of the following" or its similar expression refers to any combination of these items, including any combination of single item (one) or plural items (ones). For example, at least one (one) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a, b, and c", where a, b, and c can be single or multiple.

[0163] It should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0164] The steps of the methods or algorithms described in connection with the embodiments disclosed herein may be implemented directly in hardware, in software modules executed by a processor, or in a combination thereof. The software modules may be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well known in the art.

[0165] The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A speed difference shifting test method, characterized in that, the test method is applied to a speed difference shifting test system, the speed difference shifting test system includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device and an output motor, the fixing device fixes the transmission on the bench base, and the output shaft of the transmission is connected to the output motor; the method includes: the host computer obtains a target speed difference and a target gear; the host computer determines the target speed of the output shaft of the transmission according to the target speed difference; the host computer sends the target speed to the bench control system and sends the target gear to the transmission control unit; when the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, the transmission control unit drives the gear of the shift fork assembly in the transmission to become the target gear.

2. The method according to claim 1, characterized in that, the determination method of the target speed difference is as follows: the host computer determines the theoretical speed difference required for the first working condition according to the shifting diagram; the host computer collects the measured speed difference required for the second working condition; the host computer takes the theoretical speed difference and the measured speed difference as the target speed difference respectively.

3. The method according to claim 1, characterized in that, the method further includes: the host computer determines a plurality of pending pre-shift gears for one target gear; the host computer determines the required output shaft speeds respectively corresponding to the plurality of pending pre-shift gears according to the target gear, the target speed difference and the plurality of pending pre-shift gears; the host computer determines the pre-shift gear from the plurality of pending pre-shift gears according to the plurality of required output shaft speeds; the host computer determines the target speed of the output shaft of the transmission according to the target speed difference, including: the host computer determines the target speed of the output shaft of the transmission according to the target speed difference and the pre-shift gear; when the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, the transmission control unit drives the gear of the shift fork assembly in the transmission to become the target gear, including: when the bench control system controls the speed of the output shaft of the transmission to reach the target speed through the output motor, the transmission control unit drives the gear of the shift fork assembly in the transmission to first become the pre-shift gear and then become the target gear.

4. The method according to claim 3, characterized in that, the host computer determines the pre-shift gear from the plurality of pending pre-shift gears according to the plurality of required output shaft speeds, including: the host computer determines the pre-shift gear from the plurality of pending pre-shift gears according to the similarity of the plurality of required output shaft speeds.

5. The method according to claim 3, characterized in that, the transmission control unit drives the gear of the shift fork assembly in the transmission to first become the pre-shift gear and then become the target gear, including: The transmission control unit drives the shift fork assembly in the transmission to first change to the preselected gear. After the preselected gear is successfully engaged, a command to disengage the preselected gear is issued, and after a first preset time from the issuance of the command to disengage the preselected gear, it changes to the target gear.

6. The method according to any one of claims 1-5, wherein, the method further includes: The host computer obtains a plurality of speed differences to be adjusted, respectively uses the plurality of speed differences to be adjusted as the target speed differences, executes the method according to claim 1, and the execution interval is a second preset time.

7. The method according to any one of claims 1-5, wherein, the method further includes: The host computer obtains a plurality of speed differences to be adjusted, respectively uses the plurality of speed differences to be adjusted as the target speed differences, and executes the method according to claim 1 multiple times.

8. A speed-difference shift test system, wherein, the speed-difference shift test system includes a bench control system, a transmission control unit, a host computer, a bench base, a transmission, a fixing device, and an output motor; The host computer is configured to obtain a target speed difference and a target gear, determine the target speed of the output shaft of the transmission according to the target speed difference, send the target speed to the bench control system, and send the target gear to the transmission control unit; The bench control system is configured to control the speed of the output shaft of the transmission to reach the target speed through the output motor; wherein, the output shaft of the transmission is connected to the output motor; The transmission control unit is configured to drive the shift fork assembly in the transmission to change to the target gear. The fixing device is configured to fix the transmission to the bench base.

9. A computer device, wherein, the device includes a processor and a memory: The memory is configured to store program code and transmit the program code to the processor; The processor is configured to execute the method according to any one of claims 1-7 according to the instructions in the program code.

10. A computer-readable storage medium, wherein, the computer-readable storage medium is configured to store a computer program, and the computer program is configured to execute the method according to any one of claims 1-7.

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