Vehicle sliding control method and related device

Abstract

The invention discloses a vehicle sliding control method. The method comprises the steps that in response to the fact that the speed difference between the engine rotating speed and the clutch input shaft rotating speed is larger than a first preset speed difference and the brake pedal opening degree is smaller than a first preset opening degree, the first vehicle speed of a vehicle is obtained; according to the engine idle speed of the vehicle, the gearbox speed ratio and the first vehicle speed, the target vehicle speed of the vehicle is calculated; calculating the actual speed of the vehicle according to the rotating speed of the gearbox output shaft; calculating the speed error of the vehicle; through a preset control algorithm, the control torque of the vehicle is calculated according to the vehicle speed error; and controlling an engine of the vehicle to operate according to the control torque. The speed of the vehicle and the control torque of the engine are corrected according to the rotating speed of a clutch input shaft, the rotating speed of a gearbox output shaft, the rotating speed of the engine and the idling speed of the engine, so that the speed of the vehicle deviates from the idling speed of the engine, and noise and pause caused by disconnection and combination when the speed of the clutch is close to the idling speed of the engine are avoided; and therefore, the vehicle driving comfort of the driver is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a vehicle sliding control method and related devices. Background Art

[0002] With the development of vehicle technology, automatic transmission (AT) is increasingly used in vehicles. Due to its advantages such as fast gear shift response, high transmission efficiency, small power loss and good fuel economy, vehicles equipped with AT are becoming more and more popular in the market.

[0003] Due to the idle characteristics of the engine, vehicles equipped with AT require special control of the clutch. Taking the Automatic Mechanical Transmission (AMT) or Dual Clutch Transmission (DCT) as an example, due to the idle characteristics of the engine, when the calculated result of the vehicle speed reversely converted to the engine end is lower than the engine idle speed, the clutch needs to be opened to prevent stalling, and when the calculated result of the vehicle speed reversely converted to the engine end is higher than a certain value of the engine idle speed, the clutch needs to be fully engaged to reduce clutch slippage.

[0004] To achieve the above control objectives, the current control method requires that the clutch be fully engaged when the vehicle speed is higher than the engine idle speed, and that slip control be used when the vehicle speed is lower than the idle speed. However, this method is not very applicable in some scenarios such as rapid changes in road conditions. Since the vehicle speed will also change rapidly when the road conditions change rapidly, the vehicle speed may fluctuate above and below the engine idle speed, which will cause the clutch to open and engage with the fluctuation of the vehicle speed. The vehicle will also experience noise and setbacks due to changes in the clutch state, thereby reducing the driver's driving experience. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a vehicle coasting control method and related devices.

[0006] The embodiments of the present application disclose the following technical solutions:

[0007] In a first aspect, an embodiment of the present application discloses a vehicle sliding control method, the method comprising:

[0008] Obtain the vehicle's clutch input shaft speed, gearbox output shaft speed, engine speed and engine idle speed;

[0009] In response to determining that the speed difference between the engine speed of the vehicle and the clutch input shaft speed is greater than a first preset speed difference, and the brake pedal opening of the vehicle is less than a first preset opening, obtain the first vehicle speed of the vehicle;

[0010] According to the engine idle speed of the vehicle, the transmission ratio, and the first vehicle speed, calculate the target vehicle speed of the vehicle;

[0011] According to the transmission output shaft speed, calculate the actual vehicle speed of the vehicle;

[0012] According to the target vehicle speed and the actual vehicle speed, calculate the vehicle speed error of the vehicle;

[0013] Through a preset control algorithm, according to the vehicle speed error, calculate the control torque of the vehicle;

[0014] Control the engine of the vehicle to operate according to the control torque.

[0015] Optionally, the method further includes:

[0016] In response to determining that the clutch input shaft speed is less than a speed threshold, control the clutch of the vehicle to open;

[0017] Control the engine of the vehicle to increase the current torque of the engine to a preset torque.

[0018] Optionally, the calculating the target vehicle speed of the vehicle according to the engine idle speed of the vehicle, the transmission ratio, and the first vehicle speed includes:

[0019] According to the engine idle speed of the vehicle, the transmission ratio, and a preset speed difference correction value, calculate the expected vehicle speed of the vehicle;

[0020] Determine the maximum value of the current speed and the expected speed as the target vehicle speed of the vehicle.

[0021] Optionally, the method further includes:

[0022] In response to determining that the speed difference between the engine speed of the vehicle and the clutch input shaft speed is greater than a second preset speed difference, and the brake pedal opening of the vehicle is greater than a first preset opening, according to the brake pedal opening and the first vehicle speed, based on a preset correspondence relationship between a plurality of the brake pedal openings and a plurality of the first vehicle speeds, determine the control torque of the vehicle.

[0023] Optionally, the method further includes:

[0024] In response to determining that the brake pedal opening is greater than a second preset opening, obtain the second vehicle speed of the vehicle;

[0025] In response to determining that the brake pedal opening is less than the second preset opening, the vehicle speed of the vehicle is controlled to change from the second vehicle speed to the expected vehicle speed at a first preset rate.

[0026] Optionally, the method further includes:

[0027] The minimum value of a first preset engine idle speed and a second preset engine idle speed is determined as the engine request idle speed of the vehicle; the first preset engine idle speed is calculated based on the clutch input shaft speed and a third preset speed difference; the second preset engine idle speed is calculated based on the engine idle speed and a fourth preset speed difference;

[0028] An engine of the vehicle is controlled to idle according to the engine request.

[0029] Optionally, the method further includes:

[0030] In response to determining that the clutch speed is greater than a sum of the engine requested idle speed and a fifth preset speed difference, the clutch of the vehicle is controlled to engage at a second preset rate.

[0031] In a second aspect, an embodiment of the present application discloses a vehicle sliding control device, characterized in that the device comprises:

[0032] A first acquisition unit is used to acquire the clutch input shaft speed, the gearbox output shaft speed, the engine speed and the engine idle speed of the vehicle;

[0033] a second acquisition unit, configured to acquire a first vehicle speed of the vehicle in response to determining that a speed difference between an engine speed of the vehicle and a speed of an input shaft of the clutch is greater than a first preset speed difference, and a brake pedal opening of the vehicle is less than a first preset opening;

[0034] a first calculation unit, configured to calculate a target vehicle speed of the vehicle according to an engine idle speed of the vehicle, a gearbox speed ratio and the first vehicle speed;

[0035] A second calculation unit, used for calculating the actual speed of the vehicle according to the speed of the output shaft of the gearbox;

[0036] A third calculation unit, configured to calculate a speed error of the vehicle according to the target speed and the actual speed;

[0037] a fourth calculation unit, configured to calculate a control torque of the vehicle according to the vehicle speed error by using a preset control algorithm;

[0038] The first engine control unit is used to control the engine of the vehicle to operate according to the control torque.

[0039] Optionally, the device further comprises:

[0040] a first clutch control unit, for controlling the clutch of the vehicle to open in response to determining that the speed of the clutch input shaft is less than a speed threshold;

[0041] The second engine control unit is used to control the engine of the vehicle to increase the current torque of the engine to a preset torque.

[0042] Optionally, the first computing unit is further used for:

[0043] Calculating the expected speed of the vehicle according to the engine idle speed, the gearbox speed ratio and the preset speed difference correction value of the vehicle;

[0044] A maximum value between the current rotation speed and the expected rotation speed is determined as a target vehicle speed of the vehicle.

[0045] Optionally, the device further comprises:

[0046] A control torque determination unit is used to determine the control torque of the vehicle in response to determining that the speed difference between the engine speed of the vehicle and the clutch input shaft speed is greater than a second preset speed difference, and the brake pedal opening of the vehicle is greater than a first preset opening, according to the brake pedal opening and the first vehicle speed, based on a preset correspondence between multiple brake pedal openings and multiple first vehicle speeds.

[0047] Optionally, the device further comprises:

[0048] a third acquisition unit, configured to acquire a second vehicle speed of the vehicle in response to determining that the brake pedal opening is greater than a second preset opening;

[0049] The vehicle speed control unit is used for controlling the vehicle speed of the vehicle to change from the second vehicle speed to the expected vehicle speed at a first preset rate in response to determining that the brake pedal opening is less than the second preset opening.

[0050] Optionally, the device further comprises:

[0051] an idle speed determination unit, configured to determine the minimum value of a first preset engine idle speed and a second preset engine idle speed as the engine request idle speed of the vehicle; the first preset engine idle speed is calculated based on the clutch input shaft speed and a third preset speed difference; the second preset engine idle speed is calculated based on the engine idle speed and a fourth preset speed difference;

[0052] A third engine control unit is used to control the engine of the vehicle to idle according to the engine request.

[0053] Optionally, the device further comprises:

[0054] The second clutch control unit is configured to control the clutch of the vehicle to engage at a second preset speed in response to determining that the clutch speed is greater than the sum of the engine requested idle speed and a fifth preset speed difference.

[0055] In a third aspect, an embodiment of the present application discloses a computer device, wherein the computer device includes a processor and a memory:

[0056] The memory is used to store program code and transmit the program code to the processor;

[0057] The processor is used to execute the vehicle coasting control method as described in the first aspect and any optional option of the first aspect according to the instructions in the program code.

[0058] In a fourth aspect, an embodiment of the present application discloses a computer-readable storage medium, which is used to store a computer program. When the computer program is executed by a processor, it is used to execute the vehicle glide control method as described in the first aspect and any optional option of the first aspect.

[0059] It can be seen from the above technical scheme that by obtaining the clutch input shaft speed, gearbox output shaft speed, engine speed and engine idle speed of the vehicle; in response to determining that the speed difference between the engine speed and the clutch input shaft speed of the vehicle is greater than the first preset speed difference, and the brake pedal opening of the vehicle is less than the first preset opening, the first vehicle speed of the vehicle is obtained; according to the engine idle speed, gearbox speed ratio and the first vehicle speed of the vehicle, the target vehicle speed of the vehicle is calculated; according to the gearbox output shaft speed, the actual vehicle speed of the vehicle is calculated; according to the target vehicle speed and the actual vehicle speed, the vehicle speed error is calculated; through the preset control algorithm, the control torque of the vehicle is calculated according to the speed error; the engine of the vehicle is controlled to run according to the control torque. That is, the vehicle speed and the control torque of the engine are corrected according to the clutch input shaft speed, the gearbox output shaft speed, the engine speed and the engine idle speed, so that the vehicle speed and the engine idle speed deviate, so that the clutch will not be disconnected and connected due to the vehicle speed and the engine idle speed are close to each other, resulting in noise and frustration, thereby improving the comfort of the driver driving the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0061] Figure 1 A flow chart of a vehicle coasting control method provided in an embodiment of the present application;

[0062] Figure 2 A timing diagram of a vehicle coasting control method provided in an embodiment of the present application;

[0063] Figure 3 A structural block diagram of a vehicle skidding control device provided in an embodiment of the present application;

[0064] Figure 4 A structural block diagram of a computer device for vehicle coasting control provided in an embodiment of the present application. DETAILED DESCRIPTION

[0065] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0066] The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances. This is just a way of distinguishing objects with the same attributes when describing the embodiments of this application.

[0067] With the development of vehicle technology, vehicle transmission devices that can change the speed and torque transmitted from the vehicle engine to the vehicle drive wheels are constantly upgraded. The vehicle transmission device can enable the vehicle to obtain different traction and speed under various working conditions such as starting from the spot, climbing, turning, and accelerating, so that the vehicle engine can work within a more favorable working range.

[0068] With the continuous improvement of the intelligence level of vehicles, compared with the manual transmission that requires manual operation, the automatic transmission (AT) is a transmission device that can automatically shift gears according to the vehicle speed and engine speed. It can be divided into hydraulic automatic transmission, mechanical automatic transmission, electronically controlled mechanical automatic transmission and dual-clutch automatic transmission.

[0069] Due to the idle characteristics of the engine, vehicles equipped with AT require special control of the clutch. Taking AMT or DCT as an example, due to the idle characteristics of its engine, when the calculated result of the vehicle speed reversely converted to the engine end is lower than the engine idle speed, the clutch needs to be opened to prevent stalling, and when the calculated result of the vehicle speed reversely converted to the engine end is higher than a certain value of the engine idle speed, the clutch needs to be fully engaged to reduce clutch slippage.

[0070] To achieve the above control objectives, the current control method requires that the clutch be fully engaged when the vehicle speed is higher than the engine idle speed, and that slip control be used when the vehicle speed is lower than the idle speed. However, this method is not very applicable in some scenarios such as rapid changes in road conditions. Since the vehicle speed will also change rapidly when the road conditions change rapidly, the vehicle speed may fluctuate above and below the engine idle speed, which will cause the clutch to open and engage with the fluctuation of the vehicle speed. The vehicle will also experience noise and setbacks due to changes in the clutch state, thereby reducing the driver's driving experience.

[0071] There is also a control method that simulates the driver driving a manual transmission vehicle. That is, in low-speed gear, when the driver releases the accelerator, the clutch is fully opened and the vehicle coasts by inertia. This control method has good smoothness and simple control logic because the vehicle speed can be freely changed according to road conditions during coasting. However, the vehicle's inertial coasting will result in a slow response when the driver steps on the accelerator again. If the accelerator needs to be released frequently in conditions such as low-speed following, noise and impact are likely to occur, and the driving experience will deteriorate.

[0072] In order to solve the above technical problems, the embodiment of the present application provides a vehicle coasting control method and related devices. Next, the method will be introduced in conjunction with the accompanying drawings. Among them, the control method can be directly applied to the electronic control unit (Electronic Control Unit, ECU) or electronic controller of the vehicle. Figure 1 Please refer to Figure 2 , Figure 2 A timing diagram of a vehicle coasting control method provided in an embodiment of the present application is combined with Figure 2 The timing diagram shown introduces the method.

[0073] See also Figure 1 , Figure 1 A flow chart of a vehicle coasting control method provided in an embodiment of the present application. The method includes S101-S107:

[0074] S101: Obtain the vehicle's clutch input shaft speed, gearbox output shaft speed, engine speed, and engine idle speed.

[0075] Among them, engine idle speed is one of the engine operating conditions, which refers to the engine running state without load, that is, the operating condition when the clutch is in the engaged position and the transmission is in the neutral position. For AT, it can be the engine speed in the "parking" or "P" gear position.

[0076] The vehicle may be a fuel-driven internal combustion engine vehicle or a hybrid vehicle in which an electric motor and an internal combustion engine coexist, such as an extended-range hybrid vehicle, a gasoline-electric hybrid vehicle, or a plug-in hybrid vehicle. The vehicle's clutch input shaft speed, gearbox output shaft speed, and engine speed may be obtained through speed sensors, such as magnetic sensors, laser sensors, or magnetoelectric sensors.

[0077] S102: In response to determining that a speed difference between an engine speed of the vehicle and a clutch input shaft speed is greater than a first preset speed difference, and a brake pedal opening of the vehicle is less than a first preset opening, obtaining a first vehicle speed of the vehicle.

[0078] Please combine Figure 2 In the second stage, the first preset speed difference is Figure 2 The first preset speed difference and the first preset opening are generally determined according to actual vehicle calibration. In some possible implementations, the first preset speed difference can be calibrated to 50 revolutions per minute (r / min), and the first preset opening is 3%.

[0079] In the implementation method corresponding to the calibration value, when the speed difference between the vehicle's engine speed and the clutch input shaft speed is greater than 50r / min, and the brake pedal opening is less than 3%, the first vehicle speed V at this time is recorded. Frz .

[0080] S103: Calculating a target vehicle speed according to the engine idle speed, the transmission speed ratio and the first vehicle speed of the vehicle.

[0081] In some possible implementations, the wheel speed converted from the engine end to the wheel end may be calculated by the quotient of the engine idle speed and the gearbox speed ratio, thereby calculating the expected vehicle speed.

[0082] After the expected speed of the vehicle is calculated, the expected speed of the vehicle is compared with the engine idle speed of the vehicle, and the larger value is used as the target speed of the vehicle.

[0083] S104: Calculate the actual speed of the vehicle according to the transmission output shaft speed.

[0084] Among them, since the vehicle is in a certain gear, the transmission speed ratio and other information have been determined. At this time, the transmission output shaft speed can be converted to the wheel end according to the transmission output shaft speed through the transmission speed ratio in the current gear, thereby obtaining the actual vehicle speed.

[0085] S105: Calculate the vehicle speed error according to the target vehicle speed and the actual vehicle speed.

[0086] The speed error of the vehicle can be obtained by directly subtracting the target speed of the vehicle from the actual speed of the vehicle.

[0087] S106: Calculate the vehicle control torque according to the vehicle speed error using a preset control algorithm.

[0088] Among them, the preset control algorithm in the embodiment of the present application can be a fuzzy control algorithm, a proportional-integral-differential algorithm (Proportion-Integral-Differential coefficient, PID), a neural network algorithm or a synovial control algorithm and other available control algorithms.

[0089] In some possible implementations, the control torque of the vehicle may be calculated by a control algorithm as shown in the following formula:

[0090] T VehSpdCL =P VehSpd *V Error +I VehSpd V Error +D Vehspd dV Error

[0091] Where, T VehSpdCL Represents the control torque calculated by the vehicle in the closed-loop control algorithm, V Error Represents the vehicle speed error, P VehSpd Represents the P phase coefficient in the vehicle speed closed-loop control algorithm, I VehSpd It represents the I phase coefficient in the vehicle speed closed-loop control algorithm, D VehSpd Represents the D-phase coefficient in the vehicle speed closed-loop control algorithm.

[0092] S107: Control the engine of the vehicle to operate according to the control torque.

[0093] Among them, the above acquisition method can be performed by corresponding sensors in various actuator components of the vehicle, and then the signals obtained from each actuator component are converted into electrical signals through the corresponding sensors, and the electrical signals are transmitted to the vehicle's ECU.

[0094] After obtaining each signal, the vehicle ECU performs the above-mentioned calculation processes according to the information contained in each signal, and finally obtains the vehicle's control torque. It then sends this signal to the controller that directly controls the vehicle's drive system and transmission system through a communication protocol bus such as the Controller Area Network (CAN), and then controls the vehicle operation through the corresponding controller.

[0095] In order to control the clutch opening when the vehicle is at a low speed and prevent the gearbox from having shaft wear noise, based on the above embodiment, the method further includes:

[0096] In response to determining that the clutch input shaft speed is less than a speed threshold, controlling a clutch of the vehicle to open;

[0097] The vehicle's engine is controlled to increase the current torque of the engine to a preset torque.

[0098] Please combine Figure 2 In part ①, when the vehicle is coasting, the input shaft speed of the clutch is less than the speed threshold, causing the vehicle to enter low-speed sliding friction control, that is, the clutch of the vehicle is controlled to open.

[0099] The speed threshold is generally determined by correcting the engine idle speed and the vehicle deceleration. The greater the deceleration, the greater the correction for the vehicle deceleration. Figure 2 As shown in offset1 in , offset1 is the correction value based on the vehicle deceleration, and the sum of the engine idle speed and offset1 is defined as the speed threshold. Generally, the specific value of the speed threshold is determined based on calibration and actual vehicle debugging.

[0100] The inventors found that when the gearbox is suddenly opened, the engine speed may be lower than the gearbox speed. In this case, the vehicle is prone to shaft noise. To prevent this from happening, a torque increase request needs to be sent to the engine during the clutch opening process to increase the engine output torque to the preset torque. The preset torque is at least the sum of the clutch torque value and the engine torque at the frozen low speed, and its calculation formula is as follows:

[0101] T EngReq =T Clutch +T EngFrz

[0102] Where, T EngReq is the preset torque of the engine, T Clutch is the clutch torque, T EngFrz The actual torque of the engine entering low speed freeze.

[0103] In order to improve the smoothness of vehicle operation and switching, based on the above embodiment, further, according to the engine idle speed, the gearbox speed ratio and the first vehicle speed of the vehicle, the target vehicle speed is calculated, including:

[0104] Calculate the expected speed of the vehicle according to the engine idle speed, gearbox speed ratio and preset speed difference correction value of the vehicle;

[0105] The maximum value between the current rotation speed and the expected rotation speed is determined as the target vehicle speed of the vehicle.

[0106] The calculation formula of the expected vehicle speed is as follows:

[0107]

[0108] In the formula, V is the expected vehicle speed, N EngIdlSpd is the engine idle speed, i trans is the transmission ratio, 80 is the preset speed difference correction value, which can be calibrated according to the actual values of the vehicle transmission and the engine. Here, 80 is taken as an example.

[0109] After determining the expected vehicle speed, the formula for determining the vehicle target speed is as follows:

[0110] V Target = Max(V Frz , V)

[0111] In the formula, V Target is the vehicle target speed, V Frz is the vehicle speed when entering the low-speed freezing state.

[0112] By introducing the preset speed difference correction value, there is a sliding friction between the clutch speed and the engine speed during the vehicle coasting process, thereby improving the smoothness of vehicle operation and switching.

[0113] When the vehicle is braking, to achieve the vehicle speed and torque control in the braking state, based on the above embodiments, further, the method further includes:

[0114] In response to determining that the speed difference between the engine speed and the clutch input shaft speed of the vehicle is greater than the second preset speed difference, and the braking pedal opening of the vehicle is greater than the first preset opening, based on the braking pedal opening and the first vehicle speed, and based on the preset correspondence between multiple braking pedal openings and multiple first vehicle speeds, determine the control torque of the vehicle.

[0115] Please continue to combine Figure 2 , such as Figure 2 shown in ③ of Figure 2 , the first preset opening is also calibrated to 3%, and the second preset speed difference is

[0116]

[0117] Table 1

[0118] In some possible implementation manners, the determination of the vehicle control torque is corrected from closed-loop control to semi-open-loop control, that is, the torque of the clutch is determined according to the braking pedal opening and the vehicle speed. Among them, the preset correspondence between multiple braking pedal openings and multiple first vehicle speeds can be pre-stored in the ECU in the form of a table, and the table is checked when the control torque needs to be determined.

[0119] Table 1 is an example of a preset corresponding relationship. In Table 1, the first row represents the brake pedal opening in percentage; the first column represents the actual vehicle speed in km / h, and other values ​​represent the actual control torque of the vehicle under the corresponding brake pedal opening and corresponding vehicle speed. For example, when the brake pedal opening of the vehicle is 10% and the first vehicle speed of the vehicle is 10 km / h, the control torque of the vehicle is determined to be 8 Nm, and other values ​​can be obtained by analogy in this way, which will not be repeated here.

[0120] In some other possible implementations, during the coasting speed closed-loop control stage, when the driver steps on the brake pedal again, that is, when the vehicle's brake pedal opening is again greater than the first preset opening, the clutch exits the speed closed-loop control and enters the semi-open loop, and the clutch torque transitions from the closed-loop control value to the semi-open-loop control value shown in Table 1. When the driver releases the brake again, the brake pedal opening is again less than the first preset opening, and the vehicle is re-frozen according to the frozen speed V Frz As a new control target vehicle speed, the clutch is controlled in accordance with the vehicle speed closed loop. In other words, the determination of the vehicle control torque can be switched between closed loop control and semi-open loop control.

[0121] In some possible implementations, based on the above embodiment, the method further includes:

[0122] In response to determining that the brake pedal opening is greater than a second preset opening, acquiring a second vehicle speed of the vehicle;

[0123] In response to determining that the brake pedal opening is less than the second preset opening, the vehicle speed is controlled to change from the second vehicle speed to the expected vehicle speed at a first preset rate.

[0124] Similar to the first preset opening, the second preset opening can also be obtained through calibration, and the second preset opening is generally different from the first preset opening.

[0125] Please continue to combine Figure 2 In part ④, if the second preset opening is calibrated to 2%, then when the brake pedal opening is greater than 2% and the vehicle speed is less than the expected speed, the brake is released again and the brake pedal opening is less than 2% again. The vehicle speed at this time is controlled through a closed loop, and transitions from the second vehicle speed at this time to the expected vehicle speed calculated based on the idle speed at a certain speed, wherein the transition speed is calibrated according to the actual vehicle situation, and then the control torque is calculated again according to the vehicle speed.

[0126] During the coasting control process, when the driver steps on the accelerator again, in order to improve the power response and smoothness of the vehicle, based on the above embodiment, the method further includes:

[0127] The minimum value of the first preset engine idle speed and the second preset engine idle speed is determined as the engine request idle speed of the vehicle; the first preset engine idle speed is calculated based on the clutch input shaft speed and the third preset speed difference; the second preset engine idle speed is calculated based on the engine idle speed and the fourth preset speed difference;

[0128] The vehicle's engine is controlled to idle according to the engine request.

[0129] Please continue to combine Figure 2 Part ⑥ of the figure, wherein the engine requested idle speed can be calculated by the following formula:

[0130] N EngReq =Min(N Clutch +Offset,N EngIdlSpd +Offset3)

[0131] Where N EngReq Request idle speed for the engine, N Clutch is the clutch input shaft speed. Offset is the deviation introduced to prevent the engine and gearbox from being jerked when combined. The size of this deviation is calibrated according to the actual vehicle test, for example, 50-200r / min. During the actual vehicle test, the clutch slip friction, engine speed noise and vehicle roughness (Noise Vibration and Harshness, NVH) are tested to determine the offset value.

[0132] In order to prevent the speed from continuing to rise and causing additional noise, Offset3 is introduced in the formula, where Offset3 can also be calibrated in advance, for example, and can be calibrated to 500r / min, and its specific value is also calibrated according to actual vehicle tests.

[0133] When the vehicle is running in a downhill condition, in order to achieve vehicle speed and torque control, based on the above embodiment, the method further includes:

[0134] In response to determining that the clutch speed is greater than the sum of the engine requested idle speed and a fifth preset speed difference, the clutch of the vehicle is controlled to engage at a second preset rate.

[0135] Please continue to combine Figure 2 In the fifth part, when the clutch speed is greater than the engine requested idle speed by more than the fifth preset speed difference Offset4, that is, when the condition is as shown in the following formula:

[0136] N Clch >N EgngReq +Offset4

[0137] At this time, the clutch needs to be controlled to engage slowly. The second preset speed required for the specific engagement can be determined by calibration until the speed difference between the engine and the clutch is eliminated, the clutch enters a locked state, and the slip control is exited.

[0138] See also Figure 3 , Figure 3 This is a structural block diagram of a vehicle skidding control device provided in an embodiment of the present application. The device comprises:

[0139] The first acquisition unit 310 is used to acquire the clutch input shaft speed, the gearbox output shaft speed, the engine speed and the engine idle speed of the vehicle;

[0140] A second acquisition unit 320, configured to acquire a first vehicle speed of the vehicle in response to determining that a speed difference between an engine speed of the vehicle and a speed of an input shaft of the clutch is greater than a first preset speed difference, and a brake pedal opening of the vehicle is less than a first preset opening;

[0141] A first calculation unit 330 is used to calculate a target vehicle speed of the vehicle according to an engine idle speed of the vehicle, a gearbox speed ratio and the first vehicle speed;

[0142] A second calculation unit 340 is used to calculate the actual speed of the vehicle according to the speed of the output shaft of the gearbox;

[0143] A third calculation unit 350 is used to calculate a speed error of the vehicle according to the target speed and the actual speed;

[0144] A fourth calculation unit 360, configured to calculate a control torque of the vehicle according to the vehicle speed error by using a preset control algorithm;

[0145] The first engine control unit 370 is used to control the engine of the vehicle to operate according to the control torque.

[0146] As a possible implementation manner, the device further includes:

[0147] a first clutch control unit, for controlling the clutch of the vehicle to open in response to determining that the speed of the clutch input shaft is less than a speed threshold;

[0148] The second engine control unit is used to control the engine of the vehicle to increase the current torque of the engine to a preset torque.

[0149] As a possible implementation manner, the first computing unit is further configured to:

[0150] Calculating the expected speed of the vehicle according to the engine idle speed, the gearbox speed ratio and the preset speed difference correction value of the vehicle;

[0151] A maximum value between the current rotation speed and the expected rotation speed is determined as a target vehicle speed of the vehicle.

[0152] As a possible implementation manner, the device further includes:

[0153] A control torque determination unit is used to determine the control torque of the vehicle in response to determining that the speed difference between the engine speed of the vehicle and the clutch input shaft speed is greater than a second preset speed difference, and the brake pedal opening of the vehicle is greater than a first preset opening, according to the brake pedal opening and the first vehicle speed, based on a preset correspondence between multiple brake pedal openings and multiple first vehicle speeds.

[0154] As a possible implementation manner, the device further includes:

[0155] a third acquisition unit, configured to acquire a second vehicle speed of the vehicle in response to determining that the brake pedal opening is greater than a second preset opening;

[0156] The vehicle speed control unit is used for controlling the vehicle speed of the vehicle to change from the second vehicle speed to the expected vehicle speed at a first preset rate in response to determining that the brake pedal opening is less than the second preset opening.

[0157] As a possible implementation manner, the device further includes:

[0158] an idle speed determination unit, configured to determine the minimum value of a first preset engine idle speed and a second preset engine idle speed as the engine request idle speed of the vehicle; the first preset engine idle speed is calculated based on the clutch input shaft speed and a third preset speed difference; the second preset engine idle speed is calculated based on the engine idle speed and a fourth preset speed difference;

[0159] A third engine control unit is used to control the engine of the vehicle to idle according to the engine request.

[0160] As a possible implementation manner, the device further includes:

[0161] The second clutch control unit is configured to control the clutch of the vehicle to engage at a second preset speed in response to determining that the clutch speed is greater than the sum of the engine requested idle speed and a fifth preset speed difference.

[0162] It can be seen from the above technical scheme that by obtaining the clutch input shaft speed, gearbox output shaft speed, engine speed and engine idle speed of the vehicle; in response to determining that the speed difference between the engine speed and the clutch input shaft speed of the vehicle is greater than the first preset speed difference, and the brake pedal opening of the vehicle is less than the first preset opening, the first vehicle speed of the vehicle is obtained; according to the engine idle speed, gearbox speed ratio and the first vehicle speed of the vehicle, the target vehicle speed of the vehicle is calculated; according to the gearbox output shaft speed, the actual vehicle speed of the vehicle is calculated; according to the target vehicle speed and the actual vehicle speed, the vehicle speed error is calculated; through the preset control algorithm, the control torque of the vehicle is calculated according to the speed error; the engine of the vehicle is controlled to run according to the control torque. That is, the vehicle speed and the control torque of the engine are corrected according to the clutch input shaft speed, the gearbox output shaft speed, the engine speed and the engine idle speed, so that the vehicle speed and the engine idle speed deviate, so that the clutch will not be disconnected and connected due to the vehicle speed and the engine idle speed are close to each other, resulting in noise and frustration, thereby improving the comfort of the driver driving the vehicle.

[0163] See also Figure 4 , Figure 4 This is a block diagram of a computer device for vehicle coasting control provided in an embodiment of the present application. The computer device includes a processor 410 and a memory 420:

[0164] The memory 420 is used to store program codes and transmit the program codes to the processor 410;

[0165] The processor 410 is used to execute the vehicle coasting control method described in any one of the above embodiments according to the instructions in the program code.

[0166] In a fourth aspect, an embodiment of the present application discloses a computer-readable storage medium, which is used to store a computer program. When the computer program is executed by a processor, it is used to execute the vehicle glide control method described in any one of the above embodiments.

[0167] It is understandable that the method can be applied to a processing device, which is a processing device capable of performing motion control, for example, a terminal device or a server with a motion control function. The method can be executed independently by a terminal device or a server, or can be applied to a network scenario in which a terminal device and a server communicate, and is executed by the cooperation of the terminal device and the server. Among them, the terminal device can be a computer, a mobile phone and other devices. The server can be understood as an application server or a Web server. In actual deployment, the server can be an independent server or a cluster server.

[0168] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the above-mentioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the above-mentioned storage medium can be at least one of the following media: read-only memory (English: read-only memory, abbreviated: ROM), RAM, magnetic disk or optical disk, etc. Various media that can store program codes.

[0169] It should be noted that each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiments. The device and system embodiments described above are merely schematic, in which the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0170] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A vehicle sliding control method, It is characterized in that The method comprises: Obtain the vehicle's clutch input shaft speed, gearbox output shaft speed, engine speed and engine idle speed; In response to determining that a speed difference between an engine speed of the vehicle and a speed of the clutch input shaft is greater than a first preset speed difference, and a brake pedal opening of the vehicle is less than a first preset opening, acquiring a first vehicle speed of the vehicle; Calculating a target vehicle speed of the vehicle according to an engine idle speed of the vehicle, a gearbox speed ratio and the first vehicle speed; Calculating the actual speed of the vehicle according to the output shaft speed of the gearbox; Calculating a speed error of the vehicle according to the target vehicle speed and the actual vehicle speed; Calculating the control torque of the vehicle according to the vehicle speed error by using a preset control algorithm; An engine of the vehicle is controlled to operate according to the control torque.

2. The method according to claim 1, It is characterized in that The method further comprises: In response to determining that the clutch input shaft speed is less than a speed threshold, controlling a clutch of the vehicle to open; An engine of the vehicle is controlled to increase a current torque of the engine to a preset torque.

3. The method according to claim 2, It is characterized in that The step of calculating the target vehicle speed according to the engine idle speed, the gearbox speed ratio and the first vehicle speed of the vehicle includes: Calculating the expected speed of the vehicle according to the engine idle speed, the gearbox speed ratio and the preset speed difference correction value of the vehicle; A maximum value between the current rotation speed and the expected rotation speed is determined as a target vehicle speed of the vehicle.

4. The method according to claim 1, It is characterized in that The method further comprises: In response to determining that the speed difference between the engine speed of the vehicle and the clutch input shaft speed is greater than a second preset speed difference, and the brake pedal opening of the vehicle is greater than a first preset opening, the control torque of the vehicle is determined according to the brake pedal opening and the first vehicle speed based on a preset correspondence between multiple brake pedal openings and multiple first vehicle speeds.

5. The method according to claim 1, It is characterized in that The method further comprises: In response to determining that the brake pedal opening is greater than a second preset opening, acquiring a second vehicle speed of the vehicle; In response to determining that the brake pedal opening is less than the second preset opening, the vehicle speed of the vehicle is controlled to change from the second vehicle speed to the expected vehicle speed at a first preset rate.

6. The method according to claim 1, It is characterized in that The method further comprises: The minimum value of a first preset engine idle speed and a second preset engine idle speed is determined as the engine request idle speed of the vehicle; the first preset engine idle speed is calculated based on the clutch input shaft speed and a third preset speed difference; the second preset engine idle speed is calculated based on the engine idle speed and a fourth preset speed difference; An engine of the vehicle is controlled to idle according to the engine request.

7. The method according to claim 1, It is characterized in that The method further comprises: In response to determining that the clutch speed is greater than a sum of the engine requested idle speed and a fifth preset speed difference, the clutch of the vehicle is controlled to engage at a second preset rate.

8. A vehicle sliding control device, It is characterized in that The device comprises: A first acquisition unit is used to acquire the clutch input shaft speed, the gearbox output shaft speed, the engine speed and the engine idle speed of the vehicle; a second acquisition unit, configured to acquire a first vehicle speed of the vehicle in response to determining that a speed difference between an engine speed of the vehicle and a speed of an input shaft of the clutch is greater than a first preset speed difference, and a brake pedal opening of the vehicle is less than a first preset opening; a first calculation unit, configured to calculate a target vehicle speed of the vehicle according to an engine idle speed of the vehicle, a gearbox speed ratio and the first vehicle speed; A second calculation unit, used for calculating the actual speed of the vehicle according to the speed of the output shaft of the gearbox; A third calculation unit, configured to calculate a speed error of the vehicle according to the target speed and the actual speed; a fourth calculation unit, configured to calculate a control torque of the vehicle according to the vehicle speed error by using a preset control algorithm; An engine control unit is used to control the engine of the vehicle to operate according to the control torque.

9. A computer device, It is characterized in that The computer device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the vehicle coasting control method described in any one of claims 1-7 according to the instructions in the program code.

10. A computer-readable storage medium, It is characterized in that The computer-readable storage medium is used to store a computer program, and when the computer program is executed by a processor, it is used to execute the vehicle glide control method according to any one of claims 1 to 7.

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