Vehicle adaptive cruise control method and related device

Abstract

The present application discloses a vehicle adaptive cruise control method, comprising: obtaining a target vehicle speed, clutch speed, and clutch target load torque; determining a first target throttle opening of the target vehicle in response to determining that the clutch speed is less than or equal to an engine idle threshold; determining a target engine speed of the target vehicle based on the first target throttle opening; calculating the target vehicle's engine output torque based on the vehicle speed, the target engine speed, and the clutch target load torque; and controlling the target vehicle's engine based on the engine output torque and the first target throttle opening. This method enables the engine to obtain a larger throttle opening and torque to provide sufficient load torque to the clutch, thereby providing sufficient driving force for the target vehicle to implement adaptive cruise control of the target vehicle and improve vehicle driving comfort and safety.

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, advanced driver assistance systems (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 cameras 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.

[0004] However, when the vehicle is traveling at low speeds, the clutch is in a sliding friction state and cannot fully transmit the engine's output torque according to the ADAS plan, resulting in the clutch's 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] To address the above technical issues, the present application provides a vehicle adaptive cruise control method and related apparatus. The method increases the engine output torque based on the clutch target load torque and the engine idle speed, thereby providing the clutch with sufficient load torque to achieve adaptive cruise control of the vehicle at low speeds.

[0006] The embodiments of this 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 target vehicle's speed, clutch speed, and clutch target load torque;

[0009] In response to determining that the clutch speed is less than or equal to an engine idle speed threshold, determining a first target throttle opening of the target vehicle based on the clutch target load torque and the vehicle speed; the first target throttle opening is determined based on the clutch target load torque and the vehicle speed and 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 a 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 rotational 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] Get 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 includes:

[0018] Based on 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 based on the clutch load torque;

[0024] An engine of the target vehicle is controlled based on the clutch load torque and the second target accelerator 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 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] filtering the clutch target load torque using 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 and according to a fourth preset correspondence between multiple engine oil temperatures and multiple 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 acquiring unit is used to acquire the speed of the target vehicle, the clutch speed and the clutch target load torque;

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

[0034] a target speed determining 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 configured 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 configured to:

[0038] In response to determining that the clutch rotational 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 includes:

[0040] a second acquiring unit, configured to acquire an engine speed of a target vehicle;

[0041] The first engine control unit is further configured to:

[0042] Based on 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 includes:

[0044] a third acquiring 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] The 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 includes:

[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 based on the clutch load torque;

[0048] The second engine control unit is configured 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 configured to:

[0050] In response to determining that the clutch speed is greater than the engine idle threshold and 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 includes:

[0052] a fourth acquiring unit, configured to acquire an oil temperature of the engine;

[0053] a load torque filtering unit, configured to filter the clutch target load torque using a preset filtering algorithm according to a preset filtering correction coefficient to obtain a transmission target load torque; the preset filtering correction coefficient being determined based on the engine oil temperature and 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 configured to control a 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, comprising 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] As can be seen from the above technical solution, 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, a first target throttle opening of the target vehicle is determined in a first preset correspondence relationship, wherein the first target throttle opening obtained in the first preset correspondence relationship is greater than the throttle opening directly calculated based on the clutch load torque, thereby providing greater driving force to the engine of the target vehicle, allowing the engine to provide greater engine output torque to the clutch. Then, based on the first target throttle opening, based on a second preset correspondence relationship between multiple first target throttle openings and multiple engine target speeds, the target engine speed of the target vehicle is determined; based on the vehicle speed, the target engine speed, and the clutch load torque, the target engine output torque of the target vehicle is determined; and finally, based on the engine output torque and the first target throttle opening, the target vehicle engine is controlled. That is, the engine output torque is adjusted according to the engine target speed so that the clutch load torque meets the torque requirement. Since the clutch cannot fully transmit the engine torque when the vehicle is traveling at low speed, the above scheme can enable 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 following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any 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 people in this technical field to better understand the solution of this application, the technical solution in the embodiment of this application will be clearly and completely described below in combination with the drawings in the embodiment of this application. Obviously, the described embodiment is only a part of the embodiment of this application, not all of the embodiments.

[0066] The terms "first," "second," and the like 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 precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, and are merely used to describe the manner in which objects with the same attributes are distinguished in the embodiments of this application.

[0067] With the advancement of artificial intelligence (AI), research and application are expanding across multiple fields. Simultaneously, the continuous innovation of vehicle technology is leading to the rapid development of autonomous driving technology. While fully autonomous driving is still in the laboratory research stage, ADAS systems that can simultaneously automatically control vehicle speed and steering have entered the market, enabling adaptive cruise control to some extent.

[0068] ADAS collects information through radar or cameras 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 low speeds, 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 the vehicle's acceleration and deceleration changes unable to be accurately controlled, and the vehicle's adaptive cruise control inaccurate, causing comfort and even safety issues.

[0070] To address the above technical issues, embodiments of the present application provide a vehicle adaptive cruise control method. The method determines the vehicle's current driving state based on the relationship between clutch speed and an engine idle threshold. When the vehicle is in a low-speed driving state, the method determines a first target throttle opening required based on a preset correspondence between the clutch target load torque required by the clutch and the engine speed. The method then determines the engine output torque required by the engine based on the preset correspondence between the first target throttle opening and the engine speed. The method then controls the engine of the target vehicle based on the engine output torque and the first target throttle opening, ensuring that the target vehicle receives sufficient clutch load torque. Consequently, when the clutch cannot fully transmit the engine output torque provided by the engine to the output terminal, the clutch output terminal still receives sufficient load torque to control the target vehicle for adaptive cruise control. This improves the accuracy of the vehicle's adaptive cruise control, thereby enhancing vehicle comfort and safety.

[0071] Next, a vehicle adaptive cruise control method provided by an embodiment of the present application will be described with reference to the accompanying drawings. The cruise control method can be directly applied to a vehicle's electronic control unit (ECU) or electronic controller, or it can be executed by an ADAS system. For ease of description, the ADAS system is used as the execution body 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: Obtain the target vehicle's speed, clutch speed, and clutch target load torque.

[0074] The target vehicle can be a fuel-powered internal combustion engine vehicle or a hybrid vehicle incorporating both an electric motor and an internal combustion engine, such as a range-extended hybrid vehicle, a gasoline-electric hybrid vehicle, or a plug-in hybrid vehicle. The clutch speed can be obtained using a speed sensor, such as a magnetic sensor, a laser sensor, or a magnetoelectric sensor. The clutch target load torque can be calculated based on the target vehicle's speed and the vehicle's current speed. The clutch target load torque is used to increase or decrease the current clutch load torque to achieve vehicle acceleration or deceleration.

[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, also known as the throttle valve opening, is controlled by the accelerator pedal during manual driving. The gasoline engine controls the fuel injection rate based on the throttle opening to deliver the appropriate amount of fuel to the engine's combustion chamber. The first target throttle opening for the target vehicle is used to control the amount of fuel injected into the vehicle's engine at the current clutch target load torque and current engine speed.

[0077] The first target throttle opening is determined based on a first predetermined correspondence between a plurality of clutch target load torques, a plurality of vehicle speeds, and a plurality of first target throttle openings, according to the clutch target load torque and the vehicle speed. The vehicle speed at this time is a low speed, for example, a maximum of 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] The first row of Table 1 represents the target clutch load torque of the target vehicle, in Newton-meters (N·m); the first column from the left of Table 1 represents the target vehicle speed, in km / h; and the remaining values ​​represent the first target throttle opening of the target vehicle at the corresponding clutch target load torque and the corresponding speed, where the throttle opening is expressed as a percentage of full throttle.

[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 the 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 embodiments of the present application, the engine idle speed correction value may be obtained by calibration based on the actual vehicle performance of the target vehicle, such as the gear position of the target vehicle and the acceleration of the target vehicle. For example, in some possible implementations of the embodiments of the present application, the engine idle speed correction value may 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, with the unit being kilometers per hour per second (kph / s). The first column from the left of Table 2 represents the gear position of the target vehicle, i.e., 1st gear and 2nd gear of the target vehicle. The other values ​​represent the engine idle speed correction value of the target vehicle under the corresponding gear position and 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; 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 table.

[0091] Please refer again Figure 1 S103: 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.

[0092] Since the throttle opening is used to control the amount of fuel sprayed from the gasoline engine to the vehicle engine, and 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 target engine speeds may be as shown in Table 3 below:

[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 performed by the automatic transmission control unit (TCU). In this implementation, the TCU receives the first target throttle opening from the EMS and determines the target engine speed required for this first target throttle opening through a table lookup.

[0099] Please refer to Table 1 and Table 3. When the target vehicle speed or clutch load torque is not listed in the table, the linear relationship can be used to solve the problem using the segmented values ​​of each segment. For example, when the engine speed is 10 km / h and the clutch load torque is 40 N·m, the linear relationship between 30 N·m and 50 N·m is used to calculate (30-10) / (50-30)=1. That is, at a speed of 10 km / h, the clutch load torque starts at 30 N·m. For every 1 N·m increase in clutch load torque, the first target throttle opening increases by 1%. When the clutch load torque is 40 N·m, the first target throttle opening is 10+1*(40-30)=20, which is 20% of full throttle.

[0100] The target engine speed calculation method for Table 3 can also be calculated based on 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 the 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 or low-speed state, the clutch speed can be less than or equal to the engine idle speed, that is, the vehicle is 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 relationship between the clutch speed and the engine idle speed, the gear position of the target vehicle can also be determined. According to the principle of gear-speed matching, when a vehicle is traveling at a low speed, the automatic transmission generally configures the vehicle in a lower gear. Therefore, the gear position configured by the automatic transmission can be further determined. When the automatic transmission is in 1st or 2nd gear and the clutch speed is less than or equal to the engine idle speed, the vehicle is determined to be in a low-speed state. Then, based on 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] Get 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] Based on 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] Because passengers perceive changes in speed and acceleration more clearly at slower speeds, and more slowly at faster speeds, the rate of change of engine output torque needs to be limited to achieve smooth vehicle control.

[0112] In some possible implementations of this embodiment, a determination can be made regarding the engine speed pull-down. The engine speed pull-down is the difference between the target engine speed and the actual engine speed. If the difference is larger, i.e., the actual engine speed differs significantly from the target engine speed, then the clutch load torque increases at a slower rate, i.e., the preset rate is slower, meaning the engine increases the output torque to the engine output torque at a slower rate. If the difference is smaller, i.e., the actual engine speed differs less from the target engine speed, then the clutch load torque increases at a faster rate, i.e., the preset rate is faster, meaning the engine increases the output torque to the engine output torque at a faster rate. This control method achieves smooth control of the target vehicle, reduces occupants' perception of changes in the target vehicle's speed and acceleration, and improves vehicle ride comfort.

[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 special working conditions, 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 obtained 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 based on 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] Because the target vehicle's clutch fully connects the engine to the transmission at the clutch output when the vehicle is traveling at high speed, the target vehicle can fully transfer the engine's output torque to the clutch as clutch load torque. However, when the clutch speed fluctuates around the engine idle threshold, the target vehicle's adaptive cruise control mode will switch back and forth between high and low speeds, resulting in frequent switching of control modes and detrimental to control stability.

[0123] Therefore, in some possible implementations of this 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 speed 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 50 rpm greater than the engine idle threshold before the control mode can be switched, and the engine idle threshold is 1000 rpm, a hysteresis interval of 1000 rpm-1050 rpm is left; and the clutch speed is 900 rpm, the target vehicle is now performing adaptive cruise control at a low speed; if the clutch speed reaches 1020 rpm and is not greater than 1050 rpm, the target vehicle still maintains control at a low speed; if the clutch speed reaches 1100 rpm and is greater than 1050 rpm, the target vehicle switches to a control mode at a high speed; and if the clutch speed drops again to 1020 rpm, but the clutch speed is not less than 1000 rpm at this time, the target vehicle still maintains control at a high speed; if the clutch speed continues to drop to 980 rpm, which is lower than 1000 rpm, 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, preventing frequent switching between high-speed and low-speed states and improving control stability.

[0126] To further maintain a stable control state and prevent the vehicle's 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 for the target vehicle is determined.

[0129] Since the clutch can fully connect the engine and the clutch output end at high speed, that is, it can fully transmit the engine output torque to the load end, 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, a further determination is made as to whether the speed difference between the clutch speed and the engine speed is less than a slip threshold. For example, the slip threshold may be calibrated to 50 rpm, i.e., whether the speed difference between the clutch speed and the engine speed is less than 50 rpm. Based on the vehicle's driving relationship, since the target vehicle is driven by the engine at the clutch load end, the engine speed is generally slightly higher than the clutch speed.

[0131] The vehicle state is determined by dual means based on the relationship between the clutch speed and the engine idle threshold, as well as the speed difference between the clutch speed and the engine speed. This allows the target vehicle to reduce the frequency of switching between high-speed and low-speed states, thereby further maintaining the stability of the control state and reducing the jumps between high and low speed states in the vehicle's adaptive cruise control.

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

[0133] Get the engine oil temperature;

[0134] Filtering the clutch target load torque using 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 and according to a fourth preset correspondence between multiple engine 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 clutch load end 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 capable of filtering 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 can 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] The first row of Table 4 shows the target vehicle's oil temperature in degrees Celsius (°C). The second row of Table 4 shows the preset filter correction coefficient. This preset filter correction coefficient controls the rate of change of the transmission target load torque obtained by the preset filtering algorithm. A larger preset filter correction coefficient results in a faster rate of change of the transmission target load torque, meaning it is closer to the pre-filtered clutch target load torque. A smaller preset filter correction coefficient results in a slower rate of change of the transmission target load torque, meaning it deviates from the pre-filtered clutch target load torque.

[0143] The speed of change 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 target vehicle acceleration to the TCU.

[0149] The EMS receives the clutch target load torque from the 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 the 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 block diagram of a vehicle adaptive cruise control device provided in an embodiment of the present application. The device includes:

[0152] A first acquiring unit 310 is configured to acquire a target vehicle speed, a clutch speed, and a clutch target load torque;

[0153] a first throttle opening determination unit 320 for determining, in response to determining that the clutch speed is less than or equal to an engine idle speed threshold, a first target throttle opening of the target vehicle based on the clutch target load torque and the vehicle speed; the first target throttle opening is determined based on the clutch target load torque and the vehicle speed, and 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 a 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;

[0154] a target speed determining unit 330 for 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;

[0155] an output torque determination unit 340 for calculating 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 configured 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, the first throttle opening determination unit is further configured to:

[0158] In response to determining that the clutch rotational 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, the device further includes:

[0160] a second acquiring unit, configured to acquire an engine speed of a target vehicle;

[0161] The first engine control unit is further configured to:

[0162] Based on 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, the device further includes:

[0164] a third acquiring 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] The 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, 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 based on the clutch load torque;

[0168] The second engine control unit is configured 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, the second throttle opening determination unit is further configured to:

[0170] In response to determining that the clutch speed is greater than the engine idle threshold and 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, the device further includes:

[0172] a fourth acquiring unit, configured to acquire an oil temperature of the engine;

[0173] a load torque filtering unit, configured to filter the clutch target load torque using 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 and according to a fourth preset correspondence between multiple engine oil temperatures and multiple preset filtering correction coefficients;

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

[0175] As can be seen from the above technical solution, 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, a first target throttle opening of the target vehicle is determined in a first preset correspondence relationship, wherein the first target throttle opening obtained in the first preset correspondence relationship is greater than the throttle opening directly calculated based on the clutch load torque, thereby providing greater driving force to the engine of the target vehicle, allowing the engine to provide greater engine output torque to the clutch. Then, based on the first target throttle opening, based on a second preset correspondence relationship between multiple first target throttle openings and multiple engine target speeds, the target engine speed of the target vehicle is determined; based on the vehicle speed, the target engine speed, and the clutch load torque, the target engine output torque of the target vehicle is determined; and finally, based on the engine output torque and the first target throttle opening, the target vehicle engine is controlled. That is, the engine output torque is adjusted according to the engine target speed so that the clutch load torque meets the torque requirement. Since the clutch cannot fully transmit the engine torque when the vehicle is traveling at low speed, the above scheme can enable 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 configured 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, 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 described in any one of the above embodiments.

[0180] It is understood that this method can be applied to a processing device capable of performing motion control, such as a terminal device or server with motion control functionality. This method can be executed independently by a terminal device or server, or it can be applied to a network scenario where a terminal device and a server communicate, with the terminal device and the server working together to execute the method. The terminal device can be a computer, a mobile phone, or other device. The server can be understood as an application server or a web server. In actual deployment, the server can be a standalone server or a clustered server.

[0181] Those skilled in the art will 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 the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred 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 be referred to the partial description of the method embodiments. The device and system embodiments described above are merely schematic, wherein 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. A person of ordinary skill in the art can understand and implement it without expending creative work.

[0183] The above is merely one specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A vehicle adaptive cruise control method, characterized in that: The method comprises: Obtaining the target vehicle's speed, clutch speed, and clutch target load torque; In response to determining that the clutch speed is less than or equal to an engine idle speed threshold, determining a first target throttle opening of the target vehicle based on the clutch target load torque and the vehicle speed; the first target throttle opening is determined based on the clutch target load torque and the vehicle speed and 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 a sum of an 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 threshold, determining a first target throttle opening of the target vehicle according to the clutch target load torque and the vehicle speed includes: In response to determining that the clutch rotational 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: Get 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 includes: Based on 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, wherein The method further comprises: In response to determining that the clutch speed is less than or equal to the engine idle threshold, obtaining an actual throttle opening of the target vehicle; When the actual throttle opening is greater than the first target throttle opening, updating the first target throttle opening according to the actual throttle opening; When the actual throttle opening is less than or equal to the first target throttle opening, the first target throttle opening is not updated.

5. The method according to claim 1, wherein 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 based on the clutch load torque; An engine of the target vehicle is controlled based on the clutch load torque and the second target accelerator 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 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; filtering the clutch target load torque using 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 and according to a fourth preset correspondence between multiple engine oil temperatures and multiple 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 acquiring unit is used to acquire the speed of the target vehicle, the clutch speed and the clutch target load torque; a first throttle opening determination unit for determining, in response to determining that the clutch speed is less than or equal to an engine idle speed threshold, a first target throttle opening of the target vehicle based on the clutch target load torque and the vehicle speed; the first target throttle opening is determined based on 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 a sum of an engine idle speed and an engine idle speed correction value, the engine idle speed correction value and the engine idle speed threshold being pre-stored in an electronic control unit of the target vehicle, and the engine idle speed correction value being greater than 0; a target speed determining 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 configured 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 includes a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is configured to execute the vehicle adaptive cruise control method according to any one of claims 1 to 7 according to 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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