Vehicle restart control method, device and equipment

Abstract

The application discloses a vehicle restart control method, device and equipment. In the case that a target vehicle meets a restart control condition and a control state is changed from a non-start control state to a start control state, restart control is performed. A calibration value is calculated according to throttle opening degree and vehicle speed information. A clutch torque is controlled to approach the calibration value at a certain torque change rate to meet a power switching condition. After the difference between the clutch torque and the calibration value is less than a threshold value, the clutch torque is controlled to remain unchanged to switch the gear of a gearbox, so as to ensure the smoothness of the power switching process, relieve impact and jerk, and linearly approach a target torque after the gear of the gearbox is switched, thereby ensuring the power of the restart. The target speed after compensation is used as an actual target speed, so that the speed of the clutch input shaft can reach the preset original target speed under the influence of the filtering effect of an engine management system and communication delay.

Description

Technical Field

[0001] This application relates to the field of vehicle start-up control technology, and more specifically, to a vehicle restart control method, device, and equipment. Background Technology

[0002] In vehicles equipped with a dual-clutch transmission (DCT), there may be instances where the wheels drag the transmission in reverse. For example, when the vehicle is coasting and the clutch is not engaged, the power transmission direction is from the wheels to the transmission. If, under these circumstances, the vehicle restarts and the clutch re-engages, and the driver presses the accelerator, the engine will drive the clutch, transmission, and wheels to rotate, thus changing the direction of power transmission.

[0003] During the process of changing the direction of power transmission, the clutch eventually goes from a slipping state to a fully engaged state. If the clutch engages too quickly, the speed at the clutch output end changes too rapidly, which can easily cause a sudden change in torque in the power transmission system, resulting in shock and jerking, which makes the overall vehicle less comfortable. Summary of the Invention

[0004] In view of the above problems, this application is made to provide a vehicle restart control method, device and equipment to mitigate the impact during vehicle restart and clutch re-engagement.

[0005] The specific plan is as follows:

[0006] Firstly, a vehicle restart control method is provided, the method comprising:

[0007] If the control state of the transmission control unit of the target vehicle is non-start control state, determine whether the target vehicle meets the preset restart control conditions.

[0008] If so, then when the control state changes from a non-start control state to a start control state, a restart control is performed, which includes the following steps:

[0009] The calibration value is calculated based on the throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed the change rate threshold and decreases with time. After the difference between the clutch torque and the calibration value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse. After the gears of the transmission have reversed, the clutch torque is controlled to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold.

[0010] The target speed is calculated based on the throttle opening and the vehicle speed information. The target speed is then compensated to obtain the compensated speed. The speed of the clutch input shaft is controlled to approach the target speed with the compensated speed as the target speed until the difference between the speed of the clutch input shaft and the target speed is less than a third difference threshold.

[0011] Optionally, when the control state changes from a non-start control state to a start control state, the method further includes: starting a timer, and ending the restart control when the timer's timing result exceeds a first time threshold.

[0012] Optionally, the method further includes:

[0013] If the timer's timing result exceeds the second time threshold, it is determined whether the target vehicle is in a deceleration state. If so, the restart control is terminated, wherein the second time threshold is less than the first time threshold.

[0014] Optionally, determining whether the target vehicle meets preset restart control conditions includes:

[0015] Determine whether the target vehicle is in neutral or a preset low gear;

[0016] When the target vehicle is in neutral, determine whether the braking state of the target vehicle is inactive. If so, determine whether the throttle opening of the target vehicle is zero. If so, it indicates that the target vehicle meets the preset restart control conditions under the current condition.

[0017] When the target vehicle is in the preset low gear, it is determined whether the braking state of the target vehicle is active. If so, it is determined whether the braking state of the target vehicle changes to inactive within a preset time. If so, it indicates that the target vehicle meets the preset restart control conditions under the current situation.

[0018] Optionally, the method further includes:

[0019] When the target vehicle's transmission control unit is in start control mode, determine whether the target vehicle is in a preset low gear. If so, perform the restart control when the target vehicle's engine speed is less than the preset target speed of the clutch input shaft, or when the target vehicle's torque control mode is in torque limiting mode.

[0020] Secondly, a vehicle restart control device is provided, the device comprising:

[0021] The judgment unit is used to determine whether the target vehicle meets the preset restart control conditions when the control state of the transmission control unit of the target vehicle is a non-start control state.

[0022] A restart control unit is configured to perform restart control when the judgment result of the judgment unit is yes and the control state changes from a non-start control state to a start control state. The restart control includes the following steps:

[0023] The calibration value is calculated based on the throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed the change rate threshold and decreases with time. After the difference between the clutch torque and the calibration value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse. After the gears of the transmission have reversed, the clutch torque is controlled to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold.

[0024] The target speed is calculated based on the throttle opening and the vehicle speed information. The target speed is then compensated to obtain the compensated speed. The speed of the clutch input shaft is controlled to approach the target speed with the compensated speed as the target speed until the difference between the speed of the clutch input shaft and the target speed is less than a third difference threshold.

[0025] Optionally, the device may also include a timing unit and an end control unit;

[0026] The timing unit is used to start the timer when the judgment result of the judgment unit is yes and the control state changes from non-start control state to start control state.

[0027] The termination control unit is used to terminate the restart control when the timing result of the timer exceeds a first time threshold.

[0028] Optionally, the termination control unit is further configured to determine whether the target vehicle is in a deceleration state if the timing result of the timer exceeds the second time threshold, and if so, terminate the restart control, wherein the second time threshold is less than the first time threshold.

[0029] Optionally, the restart control unit is further configured to determine whether the target vehicle is in a preset low gear when the control state of the transmission control unit of the target vehicle is a start control state. If so, the restart control is performed when the engine speed of the target vehicle is less than a preset target speed of the clutch input shaft, or when the torque control state of the target vehicle is a torque limiting state.

[0030] Thirdly, a vehicle restart control device is provided, including: a memory and a processor;

[0031] The memory is used to store programs;

[0032] The processor is used to execute the program to implement the various steps of the vehicle restart control method described above.

[0033] By means of the above technical solution, this application performs restart control of the target vehicle when the target vehicle meets the preset restart control conditions and the control state of the transmission control unit of the target vehicle changes from non-start control state to start control state. The restart control provided in this application can include two parts: simultaneous clutch torque control and clutch speed control. For the torque control part, firstly, a calibration value is calculated based on throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed a threshold and decreases over time, thus satisfying the power reversal condition. After the difference between the clutch torque and the calibration value is less than a first difference threshold, the clutch torque is kept constant to allow the gearbox gears to reverse, ensuring the smoothness of the power reversal process and mitigating shocks and jerks. Finally, after the gearbox gears complete the reversal, the clutch torque is controlled to linearly approach a preset target torque until the difference between the clutch torque and the target torque is less than a second difference threshold. In the final torque control stage, the clutch torque change rate remains constant to achieve a smooth start, while the clutch torque approaches the target torque, ensuring the target vehicle's restart performance. For the speed control part, firstly... The target speed is calculated based on the throttle opening and vehicle speed information. Then, compensation is applied to the target speed to obtain a compensated speed. Using this compensated speed as the target, the speed of the clutch input shaft is controlled to approach the target speed until the difference between the clutch input shaft speed and the target speed is less than a third difference threshold. The reason for compensating the target speed is that during restart control, due to the filtering effect of the engine management system and the communication delay between the transmission control unit and the engine management system, the engine speed will be difficult to reach the target speed when the target speed is used as the target. By compensating the target speed to obtain the compensated speed, and using this compensated speed as the target, the engine speed can be made closer to the target speed. It should be noted that the engine and clutch input shaft are fixedly connected, and the engine speed is the clutch input shaft speed. When the clutch is fully engaged and start-up is complete, the clutch output shaft speed is the same as the clutch input shaft speed. Attached Figure Description

[0034] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0035] Figure 1 A schematic diagram of a vehicle power transmission model;

[0036] Figure 2 An example is provided, illustrating the gear reversal process of a gearbox;

[0037] Figure 3 A schematic flowchart of a vehicle restart control method provided in an embodiment of this application;

[0038] Figure 4 This example illustrates a process for controlling clutch torque.

[0039] Figure 5 This example illustrates a process for controlling the speed of a clutch.

[0040] Figure 6 This is a schematic diagram of the structure of a vehicle restart control device provided in an embodiment of this application;

[0041] Figure 7 This is a schematic diagram of a vehicle restart control device provided in an embodiment of this application. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] Unlike the starting process of vehicles equipped with dual-clutch automatic transmissions when stationary, the restart process of such vehicles refers to the process of the clutch re-engaging after the driver presses the accelerator while the vehicle is coasting at low speed. Before restarting, the vehicle is coasting at a certain speed, and the engine is not providing power; therefore, in this condition, the wheels drag the transmission in the opposite direction. For example, before restarting, the vehicle may be in neutral coasting, with the clutch fully disengaged, and the power transmission direction is the wheels dragging the final drive and transmission in the opposite direction. Another example is when the vehicle is in a low-gear coasting state after braking before restarting; in this case, the clutch is not fully disengaged, and since the driver did not press the accelerator after braking, the engine does not inject fuel and therefore does not output power; thus, the power transmission direction is the wheels dragging the final drive, transmission, and engine in the opposite direction. If a restart is performed—by pressing the accelerator and re-engaging the clutch—while the wheels are dragging the transmission in the opposite direction, the power transmission direction will change to the engine dragging the clutch, transmission, final drive, and wheels in the opposite direction. During the aforementioned power reversal process, at least the rotation direction of the gearbox gears will change, from reverse rotation to forward rotation. Assuming the gears reach the target speed within time t, compared to the normal starting process where the gears start rotating forward from a stationary state and reach the same target speed within time t, the restart process will produce a greater impact and jerking. Since the input end of the gearbox is connected to the output end of the clutch, the output speed of the clutch needs to be controlled during the vehicle's restart process. Specifically, the clutch engagement process needs to be controlled to prevent the clutch from engaging too quickly.

[0044] Figure 1 This illustrates the power transmission model of a vehicle under normal driving conditions, combined with... Figure 1 As shown, the power output from engine EN is transmitted to the half-shafts via the first-stage flywheel J1, the second-stage flywheel, the clutch input shaft J2, the clutch output shaft J3, the gearbox input shaft J4, the gearbox output shaft J5, and the differential assembly J6, thereby driving the wheels J8 to rotate. It should be noted that the engine and clutch are fixedly connected, and the engine speed is the same as the clutch input shaft speed. When the clutch is fully engaged, the clutch output shaft speed is the same as its input shaft speed; however, when the clutch is not fully engaged, the clutch output shaft speed is not the same as its input shaft speed. The clutch output shaft is connected to the gearbox input shaft, and the clutch output shaft speed can be considered equivalent to the gearbox input shaft speed. In the power transmission system, sudden torque changes are the main cause of shocks. Possible sudden torque changes mainly originate from the engine (such as...). Figure 1 (As shown in ①) Sudden torque change, clutch (such as Figure 1 (as shown in ②) Torque mutation and shift fork (as shown in ②) Figure 1(As shown in ③) The shift ring torque changes abruptly, wherein the shift fork is located between the input shaft and the output shaft of the gearbox.

[0045] If a vehicle is restarted under the aforementioned condition where the wheels are dragging the transmission in the opposite direction, a power reversal will occur at least at the transmission, specifically, the direction of gear rotation will change. Figure 2 The diagram illustrates the power reversal process of the gearbox gears, combined with... Figure 2 As shown, the formula for calculating the impact contact force during gear reversal can be as follows:

[0046]

[0047] Where K is the contact stiffness, gap is the tooth flank clearance, and D Z Let v1 be the damping coefficient, v2 be the moment of inertia of the impact driving end, v1 be the velocity of the impact driving end, and v2 be the velocity of the impact driven end. According to a certain conversion relationship, the velocity of the impact driven end can be equivalent to the output shaft speed of the transmission, and thus equivalent to the wheel speed. The velocity of the impact driving end is transmitted from the clutch input shaft to the clutch output shaft and then to the transmission input shaft. It should be noted that when the clutch is fully disengaged, the speed of the clutch output shaft is independent of the speed of the clutch input shaft. During clutch engagement, the speed of the clutch output shaft is affected by the clutch input shaft. When the clutch is fully engaged, the speeds of the engine, clutch input shaft, clutch output shaft, and transmission input shaft are all the same. Based on the above, in order to reduce the impact contact force between gears, the velocity of the impact driving end needs to be controlled. Specifically, the speed of the clutch input shaft and its rate of change need to be controlled. This is because if the clutch input shaft speed is too high or increases too quickly, it may lead to a large impact contact force between gears, causing impact, resulting in vehicle jerking and impact noise. If the clutch input shaft speed is too low at the initial stage of power reversal, it may lead to insufficient power for restarting. Specifically, the speed and rate of change of speed can be controlled by controlling the torque.

[0048] To address the aforementioned issues, this application provides a vehicle restart control method, apparatus, and device that can mitigate the impact during vehicle restart and clutch re-engagement, and can be applied to vehicles equipped with dual-clutch automatic transmissions.

[0049] Figure 3 This is a flowchart illustrating a vehicle restart control method provided in an embodiment of this application, as shown below. Figure 3 As shown, the method may include the following steps:

[0050] Step S101: Determine whether the control state of the transmission control unit is a non-start control state. If so, proceed to step S102.

[0051] Specifically, the current control state of the transmission can be determined based on the control status signals and control queue status inside the transmission control unit of the target vehicle. The control state may include a non-start control state or a start control state.

[0052] Step S102: Determine whether the target vehicle meets the restart control conditions. If so, proceed to step S103.

[0053] The restart control condition can be characterized by the presence of a power transmission chain in the target vehicle where the wheels are reverse-dragging the transmission under the current conditions. If the vehicle is to restart under the current conditions, specifically, the driver needs to press the accelerator and re-engage the clutch. The restart control provided in this application is required to mitigate the impact during the restart process.

[0054] Step S103: When the control state changes from non-start control state to start control state, restart control is performed.

[0055] It should be noted that, under the condition that the preset conditions are met, the restart control and the start control process of the transmission control unit provided in this application embodiment are performed synchronously.

[0056] The restart control can include two parts: synchronized clutch torque control and clutch speed control.

[0057] Regarding the clutch torque control, the clutch torque can be controlled by adjusting the clutch hydraulic pressure by controlling the current of the clutch solenoid valve. It should be noted that the clutch torque refers to the torque value transmitted by the clutch, that is, the torque transmitted to the gearbox through the clutch output shaft. During the restart phase, controlling the clutch solenoid valve current controls the clutch engagement status. Figure 4 This example illustrates a process for controlling clutch torque, showing possible numerical variations in clutch torque during restart control. Figure 4 As shown, the clutch torque control may include the following steps:

[0058] Step S201: Control the clutch torque to approach the calibrated value with a torque change rate that does not exceed the change rate threshold and decreases over time.

[0059] Specifically, step S201 can be combined with Figure 4The first stage corresponds to the calibration value, which is a value calculated based on throttle opening and vehicle speed information. The calibration value can be equivalent to the critical torque condition for the gearbox gear to change from being dragged in the opposite direction to being dragged by the engine. In other words, the clutch torque being close to the calibration value can indicate that the power reversal condition is met under the current situation.

[0060] Step S202: After the difference between the clutch torque and the calibrated value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse.

[0061] Specifically, step S202 can be combined with Figure 4 The second stage corresponds to the process of gear reversal in the transmission. During this process, the clutch torque remains constant to keep the rate of change of the impact driving end constant, thereby achieving smooth gear reversal.

[0062] Step S203: After the gears of the gearbox have completed the reversal, control the clutch torque to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold.

[0063] Specifically, step S203 can be combined with Figure 4 The third stage corresponds to the target torque, which can be a target value calculated during the start-up control process of the transmission control unit. Since the vehicle's acceleration is proportional to the engine torque when the clutch is fully engaged, the target torque can be expressed as the vehicle's acceleration.

[0064] The clutch speed control section may include the following steps:

[0065] Step S301: Calculate the target rotational speed based on the throttle opening and the vehicle speed information.

[0066] Specifically, the target RPM is obtained by using throttle opening and vehicle speed as two input variables and performing a two-dimensional lookup table. The larger the throttle opening, the larger the target RPM value.

[0067] Step S302: Compensate the target rotation speed to obtain the compensated rotation speed.

[0068] Step S303: With the compensation speed as the target, control the speed of the clutch input shaft to approach the target speed until the difference between the speed of the clutch input shaft and the target speed is less than the third difference threshold.

[0069] Among them, the first difference threshold, the second difference threshold, and the third difference threshold mentioned above can characterize the degree of closeness between the actual value to be controlled and the target value, and each difference threshold can be configured according to the control accuracy to be achieved.

[0070] The reason for compensating for the target speed is that during restart control, due to the filtering effect of the engine management system and the communication delay between the transmission control unit and the engine management system, the engine speed may be difficult to reach the target speed when the target speed is used as the objective. Furthermore, in the initial stage of restart control, the engine may have a certain initial speed, resulting in a small speed difference between the engine speed and the target speed. This may lead to a lower engine torque calculated by the engine management system, resulting in insufficient starting power. Moreover, since the engine can increase its speed at a relatively large rate of change, engine speed overshoot may occur during the adjustment of the engine speed according to the target speed, causing engine speed fluctuations and potentially impacting the powertrain. Using a compensation speed slightly higher than the target speed as the actual target value for the engine speed can, to some extent, solve the engine speed overshoot problem. Therefore, by compensating for the target speed to obtain a compensation speed, and using this compensation speed as the target, the engine speed can be made closer to the target speed, ensuring power during the starting process.

[0071] Figure 5 This example illustrates a process diagram for controlling clutch speed, showing possible numerical changes in clutch speed during restart control, combined with... Figure 5 As shown, when the control state of the transmission control unit changes from non-start control state to start control state, a compensation value is added to the target speed to obtain the compensated speed, where the compensation value is as follows: Figure 5 As shown by the offset value, during restart control, the initial speed of the clutch output shaft may be zero, then gradually approaches the speed of the clutch input shaft. After the clutch is fully engaged, the speed of the clutch output shaft equals the speed of the clutch input shaft. Furthermore, the method of using the compensated speed as the actual target value of the clutch input shaft speed is also applicable to the process of starting the vehicle from a standstill.

[0072] The aforementioned vehicle restart control method performs restart control on the target vehicle when the target vehicle meets preset restart control conditions and the control state of the target vehicle's transmission control unit changes from a non-start control state to a start control state. The restart control provided in this application can include two parts: simultaneous clutch torque control and clutch speed control. For the torque control part, firstly, a calibration value is calculated based on throttle opening and vehicle speed information. The clutch torque is then controlled to approach the calibration value with a torque change rate that does not exceed a threshold and decreases over time, thus satisfying the power reversal conditions. After the difference between the clutch torque and the calibration value is less than a first difference threshold, the clutch torque is kept constant to allow the transmission gears to reverse, ensuring the smoothness of the power reversal process and mitigating shocks and jerks. Finally, after the transmission gears complete the reversal, the clutch torque is controlled to linearly approach a preset target torque until the difference between the clutch torque and the target torque... If the value is less than the second difference threshold, the rate of change of clutch torque remains constant during the final torque control phase to achieve a smooth start, while the clutch torque approaches the target torque, ensuring the power of the target vehicle's restart. For the speed control section, the target speed is first calculated based on the throttle opening and the vehicle speed information, and then the target speed is compensated to obtain the compensated speed. With the compensated speed as the target, the speed of the clutch input shaft is controlled to approach the target speed until the difference between the speed of the clutch input shaft and the target speed is less than the third difference threshold. By compensating the target speed to obtain the compensated speed, and with the compensated speed as the target, the engine speed can be made closer to the target speed, ensuring the power of the starting process.

[0073] The restart control conditions, which characterize the power transmission chain of the target vehicle where the wheel is reverse-driven by the gearbox, will be described next. In some embodiments provided in this application, determining whether the target vehicle meets the preset restart control conditions may include:

[0074] Step S401: Determine whether the target vehicle is in neutral or a preset low gear.

[0075] The preset low gear can refer to at least one gear with the lowest vehicle speed among several gears of the target vehicle, excluding reverse gear.

[0076] Step S402: When the target vehicle is in neutral, determine whether the braking state of the target vehicle is inactive. If so, determine whether the throttle opening of the target vehicle is zero. If so, it indicates that the target vehicle meets the preset restart control conditions under the current situation.

[0077] The vehicle's braking status can be determined based on the pressure signal from the brake pedal or the braking status activation signal.

[0078] Step S403: When the target vehicle is in the preset low gear, determine whether the braking state of the target vehicle is active. If so, determine whether the braking state of the target vehicle changes to inactive within a preset time. If so, it indicates that the target vehicle meets the preset restart control conditions under the current situation.

[0079] It should be noted that the judgment in step S402 can determine whether the target vehicle is in neutral coasting mode, and the judgment in step S403 can determine whether the target vehicle is in deceleration coasting mode after braking. In both of these target vehicles, there is a power chain in which the wheels reverse-drive the transmission.

[0080] In some embodiments provided in this application, when the control state changes from a non-start control state to a start control state, the method may further include: starting a timer, and ending the restart control when the timer's timing result exceeds a first time threshold.

[0081] The above-mentioned vehicle restart control method, in order to consider the thermal protection of the clutch, starts a timer at the same time as restart control begins, so that restart control ends when the timer result exceeds a first time threshold, thereby avoiding clutch overheating and hardware damage caused by the clutch being in a slipping state for a long time.

[0082] Based on the above, the method may further include:

[0083] If the timer's timing result exceeds the second time threshold, it is determined whether the target vehicle is in a deceleration state. If so, the restart control is terminated.

[0084] The second time threshold is less than the first time threshold. It should be noted that when restarting the target vehicle, the driver's intention may not be acceleration, and the target vehicle may still be decelerating for a period of time. Therefore, considering the actual driving intention, restarting control can be terminated before the timer reaches the first time threshold to avoid the clutch being in a slippery state for an extended period.

[0085] In some embodiments provided in this application, the method may further include:

[0086] When the target vehicle's transmission control unit is in start control mode, determine whether the target vehicle is in a preset low gear. If so, perform the restart control when the target vehicle's engine speed is less than the preset target speed of the clutch input shaft, or when the target vehicle's torque control mode is in torque limiting mode.

[0087] The preset low gear can be referred to the description above. It should be noted that due to factors such as communication delays or vehicle malfunctions, there may be situations where the vehicle does not meet the starting conditions under the starting control of the transmission control unit. For example, the engine speed may be lower than the preset target value, or the vehicle may be in a torque-limited state, and the clutch may not be in a slipping state after the driver presses the accelerator. The restart control method provided in this application can realize the restart of the vehicle in the above situations.

[0088] The following describes a vehicle restart control device provided in an embodiment of this application. The vehicle restart control device described below can be referred to in correspondence with the vehicle restart control method described above.

[0089] See Figure 6 , Figure 6 This is a schematic diagram of a vehicle restart control device disclosed in an embodiment of this application. Figure 6 As shown, the device may include:

[0090] The judgment unit 11 is used to determine whether the target vehicle meets the preset restart control conditions when the control state of the transmission control unit of the target vehicle is a non-start control state.

[0091] The restart control unit 12 is used to perform restart control when the judgment result of the judgment unit is yes and the control state changes from non-start control state to start control state.

[0092] Specifically, the restart control may include the following steps:

[0093] The calibration value is calculated based on the throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed the change rate threshold and decreases with time. After the difference between the clutch torque and the calibration value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse. After the gears of the transmission have reversed, the clutch torque is controlled to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold.

[0094] The target speed is calculated based on the throttle opening and the vehicle speed information. The target speed is then compensated to obtain the compensated speed. The speed of the clutch input shaft is controlled to approach the target speed with the compensated speed as the target speed until the difference between the speed of the clutch input shaft and the target speed is less than a third difference threshold.

[0095] Optionally, the process by which the determining unit 11 determines whether the target vehicle meets the preset restart control conditions may include:

[0096] Determine whether the target vehicle is in neutral or a preset low gear;

[0097] When the target vehicle is in neutral, determine whether the braking state of the target vehicle is inactive. If so, determine whether the throttle opening of the target vehicle is zero. If so, it indicates that the target vehicle meets the preset restart control conditions under the current condition.

[0098] When the target vehicle is in the preset low gear, it is determined whether the braking state of the target vehicle is active. If so, it is determined whether the braking state of the target vehicle changes to inactive within a preset time. If so, it indicates that the target vehicle meets the preset restart control conditions under the current situation.

[0099] In some embodiments provided in this application, the device may further include:

[0100] The timing unit 13 is used to start the timer when the judgment result of the judgment unit is yes and the control state changes from non-start control state to start control state;

[0101] The termination control unit 14 is used to terminate the restart control if the timing result of the timer exceeds a first time threshold.

[0102] In one possible implementation, the termination control unit 14 is further configured to determine whether the target vehicle is in a deceleration state if the timing result of the timer exceeds a second time threshold, and if so, terminate the restart control, wherein the second time threshold is less than the first time threshold.

[0103] In some embodiments provided in this application, the restart control unit 12 is further configured to determine whether the target vehicle is in a preset low gear when the control state of the transmission control unit of the target vehicle is a start control state. If so, the restart control is performed when the engine speed of the target vehicle is less than a preset clutch input shaft target speed, or when the torque control state of the target vehicle is a torque limiting state.

[0104] The vehicle restart control device provided in this application embodiment can be applied to vehicle restart control equipment, and this equipment can be applied to vehicles equipped with dual-clutch automatic transmissions. Optionally, Figure 7 A hardware structure block diagram of a vehicle restart control device is shown, with reference to... Figure 7 The hardware structure of the device may include: at least one processor 1, at least one communication interface 2, at least one memory 3, and at least one communication bus 4;

[0105] In this embodiment of the application, the number of processor 1, communication interface 2, memory 3, and communication bus 4 is at least one, and processor 1, communication interface 2, and memory 3 communicate with each other through communication bus 4;

[0106] Processor 1 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0107] Memory 3 may include high-speed RAM, and may also include non-volatile memory, such as at least one disk storage device;

[0108] The memory stores a program, which the processor can call. The program is used for:

[0109] If the control state of the transmission control unit of the target vehicle is non-start control state, determine whether the target vehicle meets the preset restart control conditions.

[0110] If so, then when the control state changes from a non-start control state to a start control state, a restart control is performed, which includes the following steps:

[0111] The calibration value is calculated based on the throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed the change rate threshold and decreases with time. After the difference between the clutch torque and the calibration value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse. After the gears of the transmission have reversed, the clutch torque is controlled to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold.

[0112] The target speed is calculated based on the throttle opening and the vehicle speed information. The target speed is then compensated to obtain the compensated speed. The speed of the clutch input shaft is controlled to approach the target speed with the compensated speed as the target speed until the difference between the speed of the clutch input shaft and the target speed is less than a third difference threshold.

[0113] Optionally, the refined and extended functions of the program can be found in the description above.

[0114] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0115] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0116] The above description of the disclosed embodiments enables those skilled in the art to make or use this 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 this application. Therefore, this application is not to 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 vehicle restart control method, characterized in that, The method includes: If the control state of the transmission control unit of the target vehicle is in a non-start control state, determine whether the target vehicle meets the preset restart control conditions. If so, then when the control state changes from a non-start control state to a start control state, a restart control is performed, which includes the following steps: The calibration value is calculated based on the throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed the change rate threshold and decreases with time. After the difference between the clutch torque and the calibration value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse. After the gears of the transmission have reversed, the clutch torque is controlled to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold. The target speed is calculated based on the throttle opening and the vehicle speed information. The target speed is then compensated to obtain the compensated speed. The speed of the clutch input shaft is controlled to approach the target speed with the compensated speed as the target speed until the difference between the speed of the clutch input shaft and the target speed is less than a third difference threshold.

2. The method according to claim 1, characterized in that, When the control state changes from a non-start control state to a start control state, the method further includes: starting a timer, and ending the restart control when the timer's timing result exceeds a first time threshold.

3. The method according to claim 2, characterized in that, The method also includes: If the timer's timing result exceeds the second time threshold, it is determined whether the target vehicle is in a deceleration state. If so, the restart control is terminated, wherein the second time threshold is less than the first time threshold.

4. The method according to any one of claims 1-3, characterized in that, Determining whether the target vehicle meets the preset restart control conditions includes: Determine whether the target vehicle is in neutral or a preset low gear; When the target vehicle is in neutral, determine whether the braking state of the target vehicle is inactive. If so, determine whether the throttle opening of the target vehicle is zero. If so, it indicates that the target vehicle meets the preset restart control conditions under the current condition. When the target vehicle is in the preset low gear, it is determined whether the braking state of the target vehicle is active. If so, it is determined whether the braking state of the target vehicle changes to inactive within a preset time. If so, it indicates that the target vehicle meets the preset restart control conditions under the current situation.

5. The method according to any one of claims 1-3, characterized in that, The method also includes: When the target vehicle's transmission control unit is in start control mode, determine whether the target vehicle is in a preset low gear. If so, perform the restart control when the target vehicle's engine speed is less than the preset target speed of the clutch input shaft, or when the target vehicle's torque control mode is in torque limiting mode.

6. A vehicle restart control device, characterized in that, The device includes: The judgment unit is used to determine whether the target vehicle meets the preset restart control conditions when the control state of the transmission control unit of the target vehicle is a non-start control state. A restart control unit is configured to perform restart control when the judgment result of the judgment unit is yes and the control state changes from a non-start control state to a start control state. The restart control includes the following steps: The calibration value is calculated based on the throttle opening and vehicle speed information. The clutch torque is controlled to approach the calibration value with a torque change rate that does not exceed the change rate threshold and decreases with time. After the difference between the clutch torque and the calibration value is less than the first difference threshold, the clutch torque is controlled to remain unchanged so that the gears of the transmission can reverse. After the gears of the transmission have reversed, the clutch torque is controlled to linearly approach the preset target torque until the difference between the clutch torque and the target torque is less than the second difference threshold. The target speed is calculated based on the throttle opening and the vehicle speed information. The target speed is then compensated to obtain the compensated speed. The speed of the clutch input shaft is controlled to approach the target speed with the compensated speed as the target speed until the difference between the speed of the clutch input shaft and the target speed is less than a third difference threshold.

7. The apparatus according to claim 6, characterized in that, The device also includes a timing unit and an end control unit; The timing unit is used to start the timer when the judgment result of the judgment unit is yes and the control state changes from non-start control state to start control state. The termination control unit is used to terminate the restart control when the timing result of the timer exceeds a first time threshold.

8. The apparatus according to claim 7, characterized in that, The termination control unit is further configured to determine whether the target vehicle is in a deceleration state if the timing result of the timer exceeds the second time threshold, and if so, terminate the restart control, wherein the second time threshold is less than the first time threshold.

9. The apparatus according to any one of claims 6-8, characterized in that, The restart control unit is further configured to determine whether the target vehicle is in a preset low gear when the control state of the transmission control unit of the target vehicle is a start control state. If so, the restart control is performed when the engine speed of the target vehicle is less than the preset target speed of the clutch input shaft, or when the torque control state of the target vehicle is a torque limiting state.

10. A vehicle restart control device, characterized in that, include: Memory and processor; The memory is used to store programs; The processor is configured to execute the program to implement each step of the vehicle restart control method as described in any one of claims 1-5.

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