Vehicle adaptive cruise control method and related device

Abstract

The invention discloses a vehicle self-adaptive cruise control method. The method comprises the steps that the vehicle speed of a target vehicle, the rotating speed of a clutch and the target load torque of the clutch are obtained; in response to the fact that the clutch rotating speed is smaller than or equal to the engine idle speed threshold value, the first target accelerator opening degree of the target vehicle is determined; according to the first target accelerator opening degree, the engine target rotating speed of the target vehicle is determined; calculating the engine output torque of the target vehicle according to the vehicle speed, the engine target rotating speed and the clutch target load torque; and controlling the engine of the target vehicle according to the engine output torque and the first target accelerator opening degree. The engine can obtain large accelerator opening degree and torque to provide enough load torque for the clutch, so that enough driving force can be provided for the target vehicle to achieve self-adaptive cruise control over the target vehicle, and the comfort and safety of vehicle driving are improved.

Description

Technical Field

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

[0002] With the improvement of vehicle automation, the Advanced Driver Assistance System (ADAS) can automatically control the vehicle's speed and steering at the same time, thereby enabling the vehicle to achieve Adaptive Cruise Control (ACC).

[0003] In related technologies, ADAS mainly collects information through radar or camera to calculate the distance to the vehicle in front, plans the output torque of the engine based on the distance to the vehicle in front, and then controls the engine according to the output torque to achieve adaptive cruise control of the vehicle.

[0004] However, when the vehicle is driving at a low speed, since the clutch is in a sliding friction state, the clutch cannot fully transmit the engine's output torque according to the ADAS plan, resulting in the clutch output end not being able to obtain sufficient load torque, making the vehicle's acceleration and deceleration changes unable to be accurately controlled, causing vehicle comfort and safety issues. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a vehicle adaptive cruise control method and related devices. The engine output torque is increased according to the clutch target load torque and the engine idle speed, so that the clutch obtains sufficient load torque to achieve adaptive cruise control of the vehicle under low speed driving state.

[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 adaptive cruise control method, the method comprising:

[0008] Obtaining the vehicle speed, clutch speed, and clutch target load torque of the target vehicle;

[0009] In response to determining that the clutch speed is less than or equal to the engine idle speed threshold, a first target throttle opening of the target vehicle is determined according to the clutch target load torque and the vehicle speed; the first target throttle opening is determined according to the clutch target load torque and the vehicle speed based on a first preset correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds and a plurality of throttle openings, the engine idle speed threshold is the sum of the engine idle speed and an engine idle speed correction value, the engine idle speed correction value and the engine idle speed threshold are pre-stored in an electronic control unit of the target vehicle, and the engine idle speed correction value is greater than 0;

[0010] Determining the target engine speed of the target vehicle according to the first target throttle opening and based on a second preset correspondence between a plurality of first target throttle openings and a plurality of target engine speeds;

[0011] Calculating the engine output torque of the target vehicle according to the vehicle speed, the target engine speed and the target clutch load torque;

[0012] An engine of the target vehicle is controlled according to the engine output torque and the first target throttle opening.

[0013] Optionally, in response to determining that the clutch speed is less than or equal to the engine idle speed, determining a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed includes:

[0014] In response to determining that the clutch speed is less than or equal to the engine idle speed, a first target throttle opening of the target vehicle is determined based on the clutch target load torque and the vehicle speed.

[0015] Optionally, the method further includes:

[0016] Obtain the engine speed of the target vehicle;

[0017] The controlling the engine of the target vehicle according to the engine output torque and the first target throttle opening comprises:

[0018] According to the engine output torque and the first target throttle opening, the engine of the target vehicle is controlled to increase the output torque to the engine output torque at a preset rate; the preset rate is based on the engine speed and the vehicle speed, and is determined according to a third preset correspondence between multiple engine speeds, multiple vehicle speeds and multiple preset rates.

[0019] Optionally, the method further includes:

[0020] In response to determining that the clutch speed is less than or equal to the engine idle speed, obtaining an actual throttle opening of the target vehicle;

[0021] When the actual throttle opening is greater than the first target throttle opening, the first target throttle opening is updated according to the actual throttle opening.

[0022] Optionally, the method further includes:

[0023] In response to determining that the clutch speed is greater than the engine idle threshold, determining a second target throttle opening of the target vehicle; the second throttle opening is calculated according to the clutch load torque;

[0024] An engine of the target vehicle is controlled according to the clutch load torque and the second target throttle opening.

[0025] Optionally, in response to determining that the clutch speed is greater than the engine idle threshold, determining a second target throttle opening of the target vehicle includes:

[0026] In response to determining that the clutch speed is greater than the engine idle threshold and that a speed difference between the clutch speed and the engine speed is less than a slip threshold, a second target throttle opening of the target vehicle is determined.

[0027] Optionally, the method further includes:

[0028] Obtaining the oil temperature of the engine;

[0029] The clutch target load torque is filtered by a preset filtering algorithm according to a preset filtering correction coefficient to obtain a transmission target load torque; the preset filtering correction coefficient is determined based on the oil temperature according to a fourth preset correspondence between a plurality of oil temperatures and a plurality of preset filtering correction coefficients;

[0030] A transmission of the target vehicle is controlled according to the transmission target load torque.

[0031] In a second aspect, an embodiment of the present application discloses a vehicle adaptive cruise control device, the device comprising:

[0032] A first acquisition unit, used to acquire a vehicle speed, a clutch speed, and a clutch target load torque of a target vehicle;

[0033] a first throttle opening determination unit, for determining a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed in response to determining that the clutch speed is less than or equal to the engine idle threshold, wherein the first target throttle opening is determined according to the clutch target load torque and the vehicle speed based on a first preset correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds and a plurality of throttle openings, the engine idle threshold being the sum of the engine idle and an engine idle correction value, the engine idle correction value and the engine idle threshold being pre-stored in an electronic control unit of the target vehicle, and the engine idle correction value being greater than 0;

[0034] a target speed determination unit, configured to determine the target engine speed of the target vehicle according to the first target throttle opening and based on a second preset correspondence between a plurality of first target throttle openings and a plurality of target engine speeds;

[0035] an output torque determination unit, configured to calculate the engine output torque of the target vehicle according to the vehicle speed, the target engine speed and the target clutch load torque;

[0036] The first engine control unit is used to control the engine of the target vehicle according to the engine output torque and the first target throttle opening.

[0037] Optionally, the first throttle opening determination unit is further used to:

[0038] In response to determining that the clutch speed is less than or equal to the engine idle speed, a first target throttle opening of the target vehicle is determined based on the clutch target load torque and the vehicle speed.

[0039] Optionally, the device further comprises:

[0040] A second acquisition unit, used to acquire the engine speed of the target vehicle;

[0041] The first engine control unit is further used for:

[0042] According to the engine output torque and the first target throttle opening, the engine of the target vehicle is controlled to increase the output torque to the engine output torque at a preset rate; the preset rate is based on the engine speed and the vehicle speed, and is determined according to a third preset correspondence between multiple engine speeds, multiple vehicle speeds and multiple preset rates.

[0043] Optionally, the device further comprises:

[0044] a third acquisition unit, configured to acquire an actual throttle opening of the target vehicle in response to determining that the clutch speed is less than or equal to the engine idle speed;

[0045] A throttle opening updating unit is configured to update the first target throttle opening according to the actual throttle opening when the actual throttle opening is greater than the first target throttle opening.

[0046] Optionally, the device further comprises:

[0047] a second throttle opening determination unit, configured to determine a second target throttle opening of the target vehicle in response to determining that the clutch speed is greater than the engine idle threshold; the second throttle opening is calculated according to the clutch load torque;

[0048] The second engine control unit is used to control the engine of the target vehicle according to the clutch load torque and the second target throttle opening.

[0049] Optionally, the second throttle opening determination unit is further used for:

[0050] In response to determining that the clutch speed is greater than the engine idle threshold and that a speed difference between the clutch speed and the engine speed is less than a slip threshold, a second target throttle opening of the target vehicle is determined.

[0051] Optionally, the device further comprises:

[0052] A fourth acquisition unit, used to acquire the oil temperature of the engine;

[0053] a load torque filtering unit, configured to filter the clutch target load torque by a preset filtering algorithm according to a preset filtering correction coefficient to obtain a transmission target load torque; the preset filtering correction coefficient is determined based on the engine oil temperature according to a fourth preset correspondence between a plurality of engine oil temperatures and a plurality of preset filtering correction coefficients;

[0054] A transmission control unit is used to control the transmission of the target vehicle according to the transmission target load torque.

[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 adaptive cruise 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 adaptive cruise 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 solution that when it is determined that the clutch speed of the target vehicle is less than or equal to the engine idle speed, that is, when it is determined that the target vehicle is in a low-speed driving state, the first target throttle opening of the target vehicle is determined in the first preset correspondence, wherein the first target throttle opening obtained in the first preset correspondence is greater than the throttle opening directly calculated by the clutch load torque, thereby providing a greater driving force for the engine of the target vehicle, so that the engine can provide a greater engine output torque for the clutch. Then, according to the first target throttle opening, based on the second preset correspondence between multiple first target throttle openings and multiple engine target speeds, the target engine speed of the target vehicle is determined; according to the vehicle speed, the target engine speed and the clutch load torque, the target engine output torque of the target vehicle is determined; finally, according to the engine output torque and the first target throttle opening, the target vehicle's engine is controlled. That is, the engine output torque is adjusted according to the engine target speed so that the clutch load torque reaches the torque requirement. Since the clutch cannot fully transmit the engine torque when the vehicle is traveling at a low speed, the above scheme enables the engine to obtain a larger throttle opening and torque to provide sufficient load torque for the clutch, thereby providing sufficient driving force for the target vehicle to achieve adaptive cruise control of the target vehicle and improve the comfort and safety of vehicle driving. 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 method for adaptive cruise control of a vehicle provided in an embodiment of the present application;

[0062] Figure 2 A schematic diagram of a vehicle adaptive cruise control device provided in an embodiment of the present application;

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

[0064] Figure 4A structural block diagram of a computer device for vehicle adaptive cruise 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 advancement of artificial intelligence technology, artificial intelligence technology has been studied and applied in many fields. At the same time, with the continuous innovation of vehicle technology, the autonomous driving technology generated by the combination of the two is developing rapidly. At present, fully autonomous driving is still in the laboratory research stage, but ADAS that can automatically control the vehicle's speed and steering at the same time has entered the market, realizing the vehicle's adaptive cruise control to a certain extent.

[0068] ADAS collects information through radar or camera to calculate the distance to the vehicle in front, plans the engine's output torque based on the distance to the vehicle in front, and then controls the engine according to the output torque to achieve adaptive cruise control of the vehicle.

[0069] However, this method of planning the output torque and controlling the engine based on it can only be used on high-speed vehicles with the clutch fully engaged. When the vehicle is traveling at a low speed, the clutch is in a sliding friction state, which makes it impossible for the clutch to fully transmit the engine output torque according to the ADAS plan, resulting in the clutch output end not being able to obtain sufficient load torque, making it impossible to accurately control the acceleration and deceleration changes of the vehicle, and making the vehicle's adaptive cruise control inaccurate, causing comfort and even safety issues.

[0070] In order to solve the above technical problems, the embodiment of the present application provides a vehicle adaptive cruise control method. The current driving state of the vehicle is judged by the magnitude relationship between the clutch speed and the engine idle threshold. When the vehicle is in a low-speed driving state, the clutch target load torque required by the clutch at this time and the engine speed at this time are determined based on a preset corresponding relationship to determine the first target throttle opening required at this time, and then the engine output torque required to be output by the engine at this time is determined according to the preset corresponding relationship between the first target throttle opening and the engine speed, and then the engine of the target vehicle is controlled according to the engine output torque and the first target throttle opening, so that the target vehicle can obtain sufficient clutch load torque, so that when the clutch cannot completely transmit the engine output torque provided by the engine to the output end, the clutch output end can still obtain sufficient load torque to control the target vehicle to perform adaptive cruise control, thereby improving the accuracy of the vehicle adaptive cruise control, and thus improving the comfort and safety of the vehicle.

[0071] Next, a vehicle adaptive cruise control method provided by an embodiment of the present application will be introduced in conjunction with the accompanying drawings. The cruise method can be directly applied to the electronic control unit (ECU) or electronic controller of the vehicle, or can be executed by the ADAS system. For the convenience of description, ADAS is used as the execution subject of the adaptive cruise control method in the relevant embodiments of the specification.

[0072] See also Figure 1 , Figure 1 A flow chart of a method for vehicle adaptive cruise control provided in an embodiment of the present application, the method comprising:

[0073] S101: Obtaining the vehicle speed, clutch speed, and clutch target load torque of the target vehicle.

[0074] The target 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 clutch speed may be obtained by a speed sensor, such as a magnetic sensor, a laser sensor or a magnetoelectric sensor; the clutch target load torque may be obtained based on the target travel speed of the target vehicle and the current travel speed of the vehicle, and the clutch target load torque may be used to increase or decrease the current load torque of the clutch to achieve acceleration or deceleration of the vehicle.

[0075] S102: In response to determining that the clutch speed is less than or equal to the engine idle threshold, determining a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed.

[0076] The throttle opening is the throttle opening, which is controlled by the accelerator pedal during manual driving by the driver. The gasoline engine controls the fuel injection amount according to the throttle opening to provide a suitable amount of fuel for the engine combustion chamber. Under the current clutch target load torque and the current engine speed, the first target throttle opening of the target vehicle is used to control the amount of fuel sprayed by the gasoline engine to the vehicle engine.

[0077] The first target throttle opening is determined according to the clutch target load torque and the vehicle speed, based on a first preset correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds and a plurality of first target throttle openings. The vehicle speed at this time is a vehicle speed in a low speed state, for example, the maximum vehicle speed is 20 km / h.

[0078] In some possible implementations of the embodiment of the present application, the first preset correspondence between multiple clutch target load torques, multiple vehicle speeds, and multiple first target throttle openings may be as shown in Table 1 below:

[0079]

[0080] Table 1

[0081] Among them, the first row of Table 1 represents the clutch target load torque of the target vehicle, in Newton meters (N·m); the first column from the left of Table 1 represents the speed of the target vehicle, in km / h, and the other values ​​represent the first target throttle opening of the target vehicle under the corresponding clutch target load torque and the corresponding speed, and the throttle opening is a percentage of the throttle fully opened.

[0082] For example: when the clutch load torque of the target vehicle is 30N·m and the vehicle speed is 10km / h, the first target throttle opening of the target vehicle is 10, that is, 10% of the throttle is fully open; when the clutch load torque of the target vehicle is 150N·m and the vehicle speed is 15km / h, the first target throttle opening of the target vehicle is 70, that is, 70% of the throttle is fully open.

[0083] The planning process of the first target throttle opening can be executed by the Engine Management System (EMS) system. For example, the EMS system receives the clutch target load torque calculated by the ADAS system and receives the speed of the target vehicle from the vehicle speed sensor, and determines the first target throttle opening of the current target vehicle by looking up a table.

[0084] The engine idle speed threshold is the sum of the engine idle speed and the engine idle speed correction value. The engine idle speed correction value and the engine idle speed threshold are pre-stored in the electronic control unit of the target vehicle. The engine idle speed correction value is greater than 0.

[0085] In the embodiment of the present application, the engine idle speed correction value can be obtained by calibration based on the actual vehicle performance of the target vehicle, and the actual vehicle performance of the vehicle is, for example, the gear of the target vehicle and the acceleration of the target vehicle. For example, in some possible implementations of the embodiment of the present application, the engine idle speed correction value can be obtained from the following Table 2:

[0086] -20 -15 -10 -5 0 5 1 200 150 100 50 0 0 2 200 150 100 50 0 0

[0087] Table 2

[0088] Among them, the first row of Table 2 represents the acceleration of the target vehicle, and the unit is kilometers per hour per second (kph / s). The first column from the left of Table 2 represents the gear of the target vehicle, that is, the 1st gear and the 2nd gear of the target vehicle. The other values ​​represent the engine idle speed correction value of the target vehicle at the corresponding gear and the corresponding acceleration. The unit of the engine idle speed correction value is revolutions per minute (r / min, rpm).

[0089] For example: when the acceleration of the target vehicle is -20kph / s and the current target vehicle is in 1st gear, the engine idle speed correction value is 200rpm; and when the acceleration of the target vehicle is -5kph / s and the current target vehicle is in 2nd gear, the engine idle speed correction value is 50rpm.

[0090] The process of determining the engine idle speed correction value can be executed by the ADAS system. For example, the ADAS receives information such as vehicle speed, clutch speed, acceleration, gear position and clutch load from various sensors, and obtains the corresponding engine idle speed correction value based on the above correspondence.

[0091] Please review Figure 1 S103: According to the first target throttle opening, based on a second preset correspondence between a plurality of first target throttle openings and a plurality of engine target speeds, determine the engine target speed of the target vehicle.

[0092] Since the throttle opening is used to control the amount of fuel sprayed from the gasoline engine to the vehicle engine, after the vehicle engine receives the corresponding amount of fuel, the vehicle engine has a certain amount of driving force to drive the vehicle engine to rotate, and this power will simultaneously affect the speed of the target vehicle engine and the engine output torque of the target vehicle, so that the engine of the target vehicle can output a suitable engine output torque.

[0093] In some possible implementations of the present embodiment, the second preset correspondence between the plurality of first target throttle openings and the plurality of engine target speeds may be as shown in the following Table 3:

[0094] 0 10 20 30 50 75 100 1000 1100 1200 1300 1500 1750 2000

[0095] Table 3

[0096] The first row of Table 3 represents the first target throttle opening of the target vehicle, and the second row represents the target engine speed of the target vehicle at the corresponding first target throttle opening, in rpm.

[0097] For example, when the first target throttle opening of the target vehicle is 50%, the target engine speed of the target vehicle is 1500 rpm.

[0098] The process of determining the target engine speed from the first target throttle opening can be completed by the automatic transmission control unit (TCU). In this implementation, the TCU receives the first target throttle opening sent by the EMS, and determines the target engine speed required under the first target throttle opening by looking up a table.

[0099] Please combine Table 1 with Table 3. When the speed or clutch load torque of the target vehicle does not appear in the table, it can be solved according to the linear relationship through the segmented value of each segment. For example: when the engine speed is 10km / h, and the clutch load torque is 40N·m at this time, according to the linear relationship between 30N·m and 50N·m, the calculation method is (30-10) / (50-30)=1, that is, at a speed of 10km / h, the clutch load torque starts from 30N·m, and the first target throttle opening increases by 1% for every 1N·m increase in the clutch load torque. When the clutch load torque is 40N·m, the first target throttle opening is 10+1*(40-30)=20, which is 20% of the throttle fully open state.

[0100] The target engine speed calculation method for Table 3 can also be calculated according to the above linear relationship. For example, when the first target throttle opening is 40%, the speed is 1300+(1500-1300) / (50-30)=1400, that is, the target engine speed at this time is 1400rpm.

[0101] S104: Calculating the engine output torque of the target vehicle according to the engine speed, the target engine speed and the target clutch load torque.

[0102] S105: Controlling the engine of the target vehicle according to the engine output torque and the first target throttle opening.

[0103] To improve the sensitivity of vehicle adaptive cruise control, based on the above embodiment, further, in response to determining that the clutch speed is less than or equal to the engine idle speed, determining a first target throttle opening of the target vehicle includes:

[0104] In response to determining that the clutch speed is less than or equal to the engine idle speed, a first target throttle opening degree of the target vehicle is determined.

[0105] Since the relationship between the clutch speed and the engine idle speed can be used to determine whether the current target vehicle is traveling in a high-speed state or a low-speed state, the clutch speed can be less than or equal to the engine idle speed, that is, the vehicle can be determined to be in a low-speed driving state, thereby guiding the vehicle to immediately switch to the adaptive cruise control in the low-speed state, thereby improving the sensitivity of the vehicle's adaptive cruise control.

[0106] In some possible implementations of this embodiment, while determining the magnitude relationship between the clutch speed and the engine idle speed, the gear position of the target vehicle can be determined. According to the gear speed matching principle, when a vehicle is generally traveling at a low speed, the automatic transmission will configure a lower gear for the vehicle. Therefore, the gear position configured by the automatic transmission can be determined again. When the gear position of the automatic transmission is in the 1st gear or the 2nd gear, and the clutch speed is less than or equal to the engine idle speed, it is determined that the vehicle is in a low speed state, and then according to the adaptive cruise control in the low speed state, the first target throttle opening of the vehicle is determined.

[0107] In order to maintain smooth vehicle control and prevent sudden changes in engine output torque, based on the above embodiment, the method further includes:

[0108] Obtain the engine speed of the target vehicle;

[0109] Controlling an engine of a target vehicle according to the engine output torque and a first target throttle opening includes:

[0110] According to the engine output torque and the first target throttle opening, the engine of the target vehicle is controlled to increase the output torque to the engine output torque at a preset rate; the preset rate is based on the engine speed and the vehicle speed, and is determined according to a third preset correspondence between multiple engine speeds, multiple vehicle speeds and multiple preset rates.

[0111] When the vehicle speed is slow, the passengers in the vehicle can feel the changes in the vehicle speed and acceleration more obviously; when the vehicle speed is fast, the passengers in the vehicle can feel the changes in the vehicle speed and acceleration more slowly. Therefore, in order to achieve the smoothness of the target vehicle control, it is necessary to limit the change rate of the engine output torque.

[0112] In some possible implementations of this embodiment, the engine speed pull-down can be judged. The engine speed pull-down is the difference between the engine target speed and the engine actual speed. If the difference is larger, that is, the actual engine speed is larger than the engine target speed, then the clutch load torque increase rate is slower, that is, the preset rate is slower, that is, the engine increases the output torque to the engine output torque at a slower speed; and if the difference is smaller, that is, the actual engine speed is smaller than the engine target speed, then the clutch load torque increase rate is faster, that is, the preset rate is faster, that is, the engine increases the output torque to the engine output torque at a faster speed. In this control method, smooth vehicle control of the target vehicle is achieved, the perception of the speed and acceleration changes of the target vehicle by the occupants in the vehicle is reduced, and the driving comfort of the vehicle is improved.

[0113] To facilitate the free switching between the driver's manual control and the vehicle's adaptive cruise control, based on the above embodiment, the method further includes:

[0114] In response to determining that the clutch speed is less than or equal to the engine idle speed, obtaining an actual throttle opening of the target vehicle;

[0115] When the actual throttle opening is greater than the first target throttle opening, the first target throttle opening is updated according to the actual throttle opening.

[0116] When the vehicle is in a special working condition, such as the vehicle needs to go up a steep slope, or the driver needs to take over manual control at any time to replace the adaptive cruise control, it is necessary to judge the actual throttle opening and the first target throttle opening.

[0117] In some possible implementations of this embodiment, the actual throttle opening can be obtained through a throttle opening sensor according to the degree to which the driver presses the accelerator pedal.

[0118] At this time, the TCU can compare the acquired first target throttle opening with the actual throttle opening. If the actual throttle opening is greater than the first target throttle opening, it is determined that the current driver requires the vehicle to change its driving state. At this time, the first target throttle opening is updated with the actual throttle opening, so that the target vehicle can be easily switched to the driver's manual control mode in real time to improve the driving experience of the target vehicle.

[0119] When the vehicle is traveling at high speed, based on the above embodiment, the method further includes:

[0120] In response to determining that the clutch speed is greater than the engine idle threshold, determining a second target throttle opening of the target vehicle; the second throttle opening is calculated according to the clutch load torque;

[0121] The engine of the target vehicle is controlled according to the clutch load torque and the second target throttle opening.

[0122] Since the clutch of the target vehicle can fully connect the engine with the gearbox at the clutch output end when the vehicle is driving at high speed, the target vehicle can fully transfer the engine output torque to the clutch as the clutch load torque. When the clutch speed fluctuates around the engine idle threshold, the adaptive cruise control mode of the target vehicle will switch back and forth between high speed and low speed, resulting in frequent switching of the control mode, which is not conducive to control stability.

[0123] Therefore, in some possible implementations of the present embodiment, in order to leave a hysteresis interval for the vehicle cruise control and reduce the frequent control switching phenomenon, the judgment conditions for high-speed vehicle driving and low-speed vehicle driving can be modified. For example, when the clutch speed is greater than the engine idle threshold by a certain amount, the target vehicle can be switched from the adaptive cruise control in the low-speed state to the adaptive cruise control in the high-speed state.

[0124] For example: assuming that the pre-set clutch speed is greater than the engine idle speed threshold of 50rpm before the control mode can be switched, and the engine idle speed threshold is 1000rpm, that is, a hysteresis interval of 1000rpm-1050rpm is left; and the clutch speed is 900rpm, at this time the target vehicle performs adaptive cruise control at a low speed; if the clutch speed reaches 1020rpm, but is not greater than 1050rpm, the target vehicle still maintains control at a low speed; if the clutch speed reaches 1100rpm, which is greater than 1050rpm, the target vehicle switches to a control mode at a high speed; and if the clutch speed drops to 1020rpm again, but the clutch speed is not less than 1000rpm at this time, the target vehicle still maintains control at a high speed; if the clutch speed continues to drop to 980rpm, which is lower than 1000rpm, the target vehicle will switch to control at a low speed again.

[0125] By setting hysteresis intervals for high-speed and low-speed control modes, switching hysteresis between high-speed and low-speed states can be achieved to prevent frequent switching between high-speed and low-speed states and improve control stability.

[0126] In order to further maintain the control state stable and prevent the vehicle adaptive cruise control from jumping, based on the above embodiment, the method further includes:

[0127] In response to determining that the clutch speed is greater than the engine idle threshold, determining a second target throttle opening of the target vehicle includes:

[0128] In response to determining that the clutch speed is greater than the engine idle threshold and the speed difference between the clutch speed and the engine speed is less than the slip threshold, a second target throttle opening of the target vehicle is determined.

[0129] Because at high speed, the clutch can fully connect the engine with the clutch output end, that is, it can fully transmit the engine output torque to the load end. Therefore, there is no speed difference or a very small speed difference between the engine speed and the clutch speed.

[0130] In some possible implementations of this embodiment, after determining that the clutch speed is greater than the engine idle speed, it is further determined whether the speed difference between the clutch speed and the engine speed is less than a slip threshold, for example, the slip threshold can be calibrated to 50rpm, that is, whether the speed difference between the clutch speed and the engine speed is less than 50rpm. Judging from the driving relationship of the vehicle, since the target vehicle is driven by the engine to the clutch load end, that is, in general, the engine speed is slightly higher than the clutch speed.

[0131] The vehicle state is double-determined by the relationship between the clutch speed and the engine idle speed threshold, as well as the speed difference between the clutch speed and the engine speed, so that the target vehicle reduces the frequency of switching between the high-speed state and the low-speed state, so as to further maintain the stability of the control state and reduce the jump between the high and low speed states of the vehicle's adaptive cruise control.

[0132] Considering the hysteresis of the transmission hydraulic system, based on the above embodiment, the method further includes:

[0133] Get the engine oil temperature;

[0134] The clutch target load torque is filtered by a preset filtering algorithm according to a preset filtering correction coefficient to obtain a transmission target load torque; the preset filtering correction coefficient is determined based on the oil temperature according to a fourth preset correspondence between multiple oil temperatures and multiple preset filtering correction coefficients;

[0135] A transmission of the target vehicle is controlled according to the transmission target load torque.

[0136] Since the load end of the clutch is generally connected to a transmission, such as an automatic transmission (AT), a dual clutch transmission (DCT) or a continuously variable transmission (CVT), and the transmission is generally a hydraulic system, there is a lag in its response to torque transmission. Therefore, this needs to be taken into consideration when controlling the transmission.

[0137] The preset filtering algorithm may be a first-order linear filter, a limiting filter, a median filter, or other filtering algorithm that can filter values ​​that change over time to control the speed at which the values ​​change.

[0138] Since the hysteresis of the hydraulic system transmission is related to the oil temperature, the higher the oil temperature in the transmission, the smaller the transmission hysteresis, that is, the faster the transmission responds to torque changes; and as the oil temperature in the transmission decreases, the transmission hysteresis increases, that is, the slower the transmission responds to torque changes. At this time, it is necessary to modify the change speed of the clutch target load torque through a filtering algorithm to obtain the transmission target load torque to control the transmission.

[0139] The corresponding relationship between multiple oil temperatures and multiple preset filter correction coefficients may be shown in Table 4 below:

[0140] -30 -20 0 20 40 60 90 0.7 0.8 0.85 0.9 0.9 0.95 1

[0141] Table 4

[0142] Among them, the first row of Table 4 represents the oil temperature of the target vehicle, in degrees Celsius (℃); the second row of Table 4 represents the preset filtering correction coefficient. The preset filtering correction coefficient is used to control the change speed of the transmission target load torque obtained by the preset filtering algorithm. The larger the preset filtering correction coefficient, the faster the change speed of the transmission target load torque, that is, the closer it is to the clutch target load torque before filtering; the smaller the preset filtering correction coefficient, the slower the change speed of the transmission target load torque, that is, it deviates from the clutch target load torque before filtering.

[0143] The change speed of the clutch load torque is changed by a preset filtering algorithm, and the preset filtering correction coefficient is changed by the change of the oil temperature to further make the transmission target load torque correspond to the hysteresis of the transmission response torque change, thereby realizing real-time torque control of the transmission of the hydraulic system.

[0144] See also Figure 2 , Figure 2 A schematic diagram of a vehicle adaptive cruise control device provided in an embodiment of the present application, the device comprising:

[0145] 210: ADAS advanced driver assistance system;

[0146] 220: TCU automatic transmission control unit;

[0147] 230: EMS engine management system.

[0148] Among them, ADAS is used to send the clutch target load torque to the EMS, and at the same time send the clutch target load torque and the target vehicle acceleration to the TCU.

[0149] EMS receives the clutch target load torque sent by ADAS, combines it with the current speed of the target vehicle, determines the first target throttle opening of the target vehicle by looking up the table, and obtains the current actual throttle opening of the target vehicle, and sends it to TCU.

[0150] The TCU receives and compares the first target throttle opening with the actual throttle opening, takes the larger value as the throttle opening for controlling the vehicle, calculates the engine output torque based on the throttle opening for controlling the vehicle, and sends the engine output torque to the EMS to control the engine of the target vehicle.

[0151] See also Figure 3 , Figure 3 This is a structural block diagram of a vehicle adaptive cruise control device provided in an embodiment of the present application. The device includes:

[0152] A first acquisition unit 310 is used to acquire the vehicle speed, clutch speed and clutch target load torque of the target vehicle;

[0153] A first throttle opening determination unit 320 is used to determine a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed in response to determining that the clutch speed is less than or equal to the engine idle speed threshold value; the first target throttle opening is determined according to the clutch target load torque and the vehicle speed based on a first preset correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds and a plurality of throttle openings, the engine idle speed threshold value is the sum of the engine idle speed and the engine idle speed correction value, the engine idle speed correction value and the engine idle speed threshold value are pre-stored in the electronic control unit of the target vehicle, and the engine idle speed correction value is greater than 0;

[0154] a target speed determination unit 330, configured to determine the target engine speed of the target vehicle according to the first target throttle opening and based on a second preset correspondence between a plurality of first target throttle openings and a plurality of target engine speeds;

[0155] an output torque determination unit 340, configured to calculate the engine output torque of the target vehicle according to the vehicle speed, the target engine speed and the target clutch load torque;

[0156] The first engine control unit 350 is used to control the engine of the target vehicle according to the engine output torque and the first target throttle opening.

[0157] As a possible implementation manner, the first throttle opening determination unit is further used for:

[0158] In response to determining that the clutch speed is less than or equal to the engine idle speed, a first target throttle opening of the target vehicle is determined based on the clutch target load torque and the vehicle speed.

[0159] As a possible implementation manner, the device further includes:

[0160] A second acquisition unit, used to acquire the engine speed of the target vehicle;

[0161] The first engine control unit is further used for:

[0162] According to the engine output torque and the first target throttle opening, the engine of the target vehicle is controlled to increase the output torque to the engine output torque at a preset rate; the preset rate is based on the engine speed and the vehicle speed, and is determined according to a third preset correspondence between multiple engine speeds, multiple vehicle speeds and multiple preset rates.

[0163] As a possible implementation manner, the device further includes:

[0164] a third acquisition unit, configured to acquire an actual throttle opening of the target vehicle in response to determining that the clutch speed is less than or equal to the engine idle speed;

[0165] A throttle opening updating unit is configured to update the first target throttle opening according to the actual throttle opening when the actual throttle opening is greater than the first target throttle opening.

[0166] As a possible implementation manner, the device further includes:

[0167] a second throttle opening determination unit, configured to determine a second target throttle opening of the target vehicle in response to determining that the clutch speed is greater than the engine idle threshold; the second throttle opening is calculated according to the clutch load torque;

[0168] The second engine control unit is used to control the engine of the target vehicle according to the clutch load torque and the second target throttle opening.

[0169] As a possible implementation manner, the second throttle opening determination unit is further used for:

[0170] In response to determining that the clutch speed is greater than the engine idle threshold and that a speed difference between the clutch speed and the engine speed is less than a slip threshold, a second target throttle opening of the target vehicle is determined.

[0171] As a possible implementation manner, the device further includes:

[0172] A fourth acquisition unit, used to acquire the oil temperature of the engine;

[0173] a load torque filtering unit, configured to filter the clutch target load torque by a preset filtering algorithm according to a preset filtering correction coefficient to obtain a transmission target load torque; the preset filtering correction coefficient is determined based on the engine oil temperature according to a fourth preset correspondence between a plurality of engine oil temperatures and a plurality of preset filtering correction coefficients;

[0174] A transmission control unit is used to control the transmission of the target vehicle according to the transmission target load torque.

[0175] It can be seen from the above technical solution that when it is determined that the clutch speed of the target vehicle is less than or equal to the engine idle speed, that is, when it is determined that the target vehicle is in a low-speed driving state, the first target throttle opening of the target vehicle is determined in the first preset correspondence, wherein the first target throttle opening obtained in the first preset correspondence is greater than the throttle opening directly calculated by the clutch load torque, thereby providing a greater driving force for the engine of the target vehicle, so that the engine can provide a greater engine output torque for the clutch. Then, according to the first target throttle opening, based on the second preset correspondence between multiple first target throttle openings and multiple engine target speeds, the target engine speed of the target vehicle is determined; according to the vehicle speed, the target engine speed and the clutch load torque, the target engine output torque of the target vehicle is determined; finally, according to the engine output torque and the first target throttle opening, the target vehicle's engine is controlled. That is, the engine output torque is adjusted according to the engine target speed so that the clutch load torque reaches the torque requirement. Since the clutch cannot fully transmit the engine torque when the vehicle is traveling at a low speed, the above scheme enables the engine to obtain a larger throttle opening and torque to provide sufficient load torque for the clutch, thereby providing sufficient driving force for the target vehicle to achieve adaptive cruise control of the target vehicle and improve the comfort and safety of vehicle driving.

[0176] See also Figure 4 , Figure 4 This is a block diagram of a computer device for vehicle adaptive cruise control provided in an embodiment of the present application. The computer device includes a processor 410 and a memory 420:

[0177] The memory 420 is used to store program codes and transmit the program codes to the processor 410;

[0178] The processor 410 is used to execute the vehicle adaptive cruise control method described in any one of the above embodiments according to the instructions in the program code.

[0179] An embodiment of the present application further discloses a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, and when the computer program is executed by a processor, the computer program is used to execute the vehicle adaptive cruise control method described in any one of the above embodiments.

[0180] 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.

[0181] 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.

[0182] 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.

[0183] 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 adaptive cruise control method, characterized in that: The method comprises: Obtaining the vehicle speed, clutch speed, and clutch target load torque of the target vehicle; In response to determining that the clutch speed is less than or equal to the engine idle speed threshold, a first target throttle opening of the target vehicle is determined according to the clutch target load torque and the vehicle speed; the first target throttle opening is determined according to the clutch target load torque and the vehicle speed based on a first preset correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds and a plurality of throttle openings, the engine idle speed threshold is the sum of the engine idle speed and an engine idle speed correction value, the engine idle speed correction value and the engine idle speed threshold are pre-stored in an electronic control unit of the target vehicle, and the engine idle speed correction value is greater than 0; Determining the target engine speed of the target vehicle according to the first target throttle opening and based on a second preset correspondence between a plurality of first target throttle openings and a plurality of target engine speeds; Calculating the engine output torque of the target vehicle according to the vehicle speed, the target engine speed and the target clutch load torque; An engine of the target vehicle is controlled according to the engine output torque and the first target throttle opening.

2. The method according to claim 1, characterized in that In response to determining that the clutch speed is less than or equal to the engine idle speed, determining a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed, comprises: In response to determining that the clutch speed is less than or equal to the engine idle speed, a first target throttle opening of the target vehicle is determined based on the clutch target load torque and the vehicle speed.

3. The method according to claim 1, characterized in that: The method further comprises: Obtain the engine speed of the target vehicle; The controlling the engine of the target vehicle according to the engine output torque and the first target throttle opening comprises: According to the engine output torque and the first target throttle opening, the engine of the target vehicle is controlled to increase the output torque to the engine output torque at a preset rate; the preset rate is based on the engine speed and the vehicle speed, and is determined according to a third preset correspondence between multiple engine speeds, multiple vehicle speeds and multiple preset rates.

4. The method according to claim 1, characterized in that: The method further comprises: In response to determining that the clutch speed is less than or equal to the engine idle speed, obtaining an actual throttle opening of the target vehicle; When the actual throttle opening is greater than the first target throttle opening, the first target throttle opening is updated according to the actual throttle opening.

5. The method according to claim 1, characterized in that The method further comprises: In response to determining that the clutch speed is greater than the engine idle threshold, determining a second target throttle opening of the target vehicle; the second throttle opening is calculated according to the clutch load torque; An engine of the target vehicle is controlled according to the clutch load torque and the second target throttle opening.

6. The method according to claim 5, characterized in that In response to determining that the clutch speed is greater than the engine idle threshold, determining a second target throttle opening of the target vehicle includes: In response to determining that the clutch speed is greater than the engine idle threshold and that a speed difference between the clutch speed and the engine speed is less than a slip threshold, a second target throttle opening of the target vehicle is determined.

7. The method according to any one of claims 1 to 6, characterized in that: The method further comprises: Obtaining the oil temperature of the engine; The clutch target load torque is filtered by a preset filtering algorithm according to a preset filtering correction coefficient to obtain a transmission target load torque; the preset filtering correction coefficient is determined based on the oil temperature according to a fourth preset correspondence between a plurality of oil temperatures and a plurality of preset filtering correction coefficients; A transmission of the target vehicle is controlled according to the transmission target load torque.

8. A vehicle adaptive cruise control device, characterized in that: The device comprises: A first acquisition unit, used to acquire a vehicle speed, a clutch speed, and a clutch target load torque of a target vehicle; a first throttle opening determination unit, for determining a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed in response to determining that the clutch speed is less than or equal to the engine idle threshold, wherein the first target throttle opening is determined according to the clutch target load torque and the vehicle speed based on a first preset correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds and a plurality of throttle openings, the engine idle threshold being the sum of the engine idle and an engine idle correction value, the engine idle correction value and the engine idle threshold being pre-stored in an electronic control unit of the target vehicle, and the engine idle correction value being greater than 0; a target speed determination unit, configured to determine the target engine speed of the target vehicle according to the first target throttle opening and based on a second preset correspondence between a plurality of first target throttle openings and a plurality of target engine speeds; an output torque determination unit, configured to calculate the engine output torque of the target vehicle according to the vehicle speed, the target engine speed and the target clutch load torque; The first engine control unit is used to control the engine of the target vehicle according to the engine output torque and the first target throttle opening.

9. A computer device, 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 adaptive cruise control method according to any one of claims 1 to 7 according to the instructions in the program code.

10. A computer-readable storage medium, 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, the computer program is used to execute the vehicle adaptive cruise control method according to any one of claims 1 to 7.

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