Vehicle control method and vehicle

Abstract

The present application provides a vehicle control method and a vehicle, wherein the vehicle control method includes obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state; when the status information of the other wheels meets a preset condition, selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy. The vehicle control method and the vehicle of the present application can be based on the ABS active alternating pressure-maintaining strategy, and can avoid the condition where the four wheels increase or decrease pressure at the same time during the operation of the ABS from a control perspective as much as possible, greatly improving the whole vehicle shaking on low-adhesion roads such as ice and snow, and improving the user experience.

Description

Technical Field

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

[0002] At present, vehicles have become one of the mainstream means of transportation for people to travel, and the safety of their brake systems has become the focus of attention of vehicle manufacturers. In actual use, it is found that when the brake pedal is pressed hard while the vehicle is driving, the wheel speed will drop rapidly. When the braking force exceeds the friction between the wheel and the ground, the wheel will be locked. A completely locked wheel will reduce the friction between the tire and the ground. Wheel locking is a phenomenon in which the brake (including disc and drum) clamps the tire, the tire has no relative movement with the brake, and the tire slides relative to the ground. The automobile anti-lock braking system (ABS) was created and developed under this safety requirement. The core control strategy of ABS is mainly based on the logic threshold control of the slip rate. Simply put, when the wheel is close to instability, it starts to maintain pressure, and when it reaches instability, it starts to release pressure, and when the wheel is close to stability, it maintains pressure, and when the wheel is completely stable, it increases pressure, and so on.

[0003] During the research process of conceiving and forming this application, the applicant discovered at least the following problems: since each wheel is independently controlled based on this strategy, it is inevitable that there will be a state of simultaneous pressure increase (all four wheels are stable) or simultaneous pressure reduction (all four wheels are unstable). This simultaneous increase and decrease will cause the whole vehicle to shake, especially on low-adhesion roads (ice and snow surfaces, or polished ice surfaces with similar friction coefficients and water-sprinkled basalt roads, etc.). Summary of the invention

[0004] In order to alleviate the above problems, the present application provides a vehicle control method, comprising:

[0005] In response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, obtaining state information of other wheels;

[0006] When the state information of the other wheels meets the preset conditions, at least one wheel is selected from the wheels in the pressure maintaining state to exit the pressure maintaining state according to a preset strategy.

[0007] Optionally, the at least one wheel includes a target wheel, and before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when a driving condition of the target wheel meets at least one of the following, it is determined that the target wheel needs to enter a pressure-maintaining state:

[0008] detecting that the adhesion of the road surface on which the target wheel is traveling is less than a first threshold;

[0009] The absolute value of the target wheel deceleration is less than a second threshold;

[0010] A jump condition in which the adhesion increases to a third threshold value is not detected;

[0011] The lateral acceleration of the target wheel is less than a fourth threshold;

[0012] The automatic emergency braking (AEB) function is not activated;

[0013] The Hill Descent Control (HDC) function is not activated;

[0014] The vehicle is in forward gear;

[0015] The currently estimated brake fluid pressure of the target wheel is greater than the locking pressure value by at least one compensation threshold value.

[0016] Optionally, the compensation threshold value includes a basic threshold value and a correction value; and the process of determining the compensation threshold value includes:

[0017] Acquire a current acceleration value of the target wheel, and determine a basic threshold value according to the current acceleration value;

[0018] Acquiring driving condition information, road adhesion information and / or vehicle speed information of the target wheel, and determining a correction value according to the driving condition information, road adhesion information and / or vehicle speed information;

[0019] The compensation threshold value of the target wheel is determined according to the basic threshold value and the correction value.

[0020] Optionally, in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, in the process of obtaining status information of other wheels, the current road surface on which the target wheel is traveling is judged according to the deceleration value of the target wheel to determine the required pressure-maintaining time of the target wheel.

[0021] Optionally, in the process of responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, the target wheel exits the pressure-maintaining state when it meets at least one of the following conditions:

[0022] The pressure holding time reaches a fifth threshold;

[0023] detecting a jump condition in which the adhesion increases to a third threshold;

[0024] detecting that the lateral acceleration value of the target wheel reaches a sixth threshold;

[0025] Automatic emergency braking (AEB) function activated;

[0026] Hill Descent Control (HDC) function activated;

[0027] The vehicle is in a non-forward gear;

[0028] The slip rate of the target wheel reaches an unstable threshold.

[0029] Optionally, the other wheels include a first wheel that is coaxial with the target wheel; when the status information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, if the first wheel is already in the pressure-maintaining state, the pressure-maintaining time of the first wheel is limited or reduced so that the first wheel exits the pressure-maintaining state earlier than the target wheel.

[0030] Optionally, the other wheels include the second wheel that first enters the pressure-maintaining state; when the status information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, if the target wheel is the last wheel to enter the pressure-maintaining state, the second wheel is controlled to directly exit the pressure-maintaining state.

[0031] Optionally, the other wheels include a third wheel that has entered a pressure-maintaining state; when the state information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, when the pressure-maintaining time of the third wheel does not reach a seventh threshold, and the slip rate of the third wheel reaches an unstable threshold, the third wheel is controlled to exit the pressure-maintaining state for pressure relief.

[0032] Optionally, the other wheels include a third wheel that has entered a pressure-maintaining state; when the status information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, when the pressure-maintaining time of the third wheel reaches a seventh threshold and the slip rate of the third wheel has not reached an unstable threshold, the third wheel is controlled to exit the pressure-maintaining state and continue to increase pressure.

[0033] The present application also provides a vehicle, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the vehicle control method as described above are implemented.

[0034] The vehicle control method and vehicle of the present application obtain status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state; when the status information of the other wheels meets a preset condition, at least one wheel is selected from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy; based on the ABS active alternating pressure-maintaining strategy, it is possible to avoid, from a control perspective, the situation in which the four wheels increase or decrease pressure at the same time during the operation of the ABS, thereby greatly improving the shaking of the entire vehicle on low-adhesion roads such as ice and snow and improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0036] Figure 1 This is a flow chart of a vehicle control method according to an embodiment of the present application.

[0037] Figure 2 Schematic diagram of control logic for active pressure maintenance of a target vehicle in one embodiment of the present application.

[0038] Figure 3 Schematic diagram of vehicle speed and wheel speed control for active pressure maintenance of a target vehicle in one embodiment of the present application.

[0039] The realization of the purpose, functional features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. The above-mentioned drawings have shown clear embodiments of this application, which will be described in more detail later. These drawings and textual descriptions are not intended to limit the scope of the concept of this application in any way, but to illustrate the concept of this application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0040] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0041] It should be noted that, in this article, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context of the specific embodiment.

[0042] In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0043] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left" and "right" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the changes in the orientation of the components in the drawings.

[0044] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0045] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0046] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] First embodiment

[0048] In one aspect, the present application provides a vehicle control method, Figure 1 This is a flow chart of a vehicle control method according to an embodiment of the present application.

[0049] like Figure 1 As shown, in one embodiment, the vehicle control method includes:

[0050] S10: In response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, obtaining state information of other wheels.

[0051] The core control strategy of ABS is mainly based on the logic threshold control of slip rate. The slip rate threshold is equal to the basic threshold plus the correction value. Among them, the basic slip rate threshold is related to acceleration, and the correction value generally refers to different driving conditions, different road surfaces, different vehicle speeds and other conditions. By comparing the actual slip rate of the current wheel with the threshold, the stability and instability of the wheel can be judged, so as to perform pressure increase, pressure reduction and pressure maintenance control. That is, when the wheel is close to instability, it starts to maintain pressure, and when it reaches instability, it starts to release pressure, and when the wheel is close to stability, it maintains pressure, and when the wheel is completely stable, it increases pressure again, and so on. The ultimate goal is to control the actual slip rate of the wheel near the target slip rate threshold, so as to ensure the maximum braking efficiency of the vehicle while taking into account stability.

[0052] When the wheels are in the pressure-maintaining state, the hydraulic pressure is kept unchanged to enter the pressure-increasing or pressure-releasing stage according to the vehicle slip rate. Exemplarily, when at least one wheel enters the pressure-maintaining state, the current pressure states of other wheels can be obtained. Exemplarily, when the braking operation is performed, the current pressure states of other wheels can include the pressure-maintaining state, the pressure-increasing state, and the pressure-reducing state.

[0053] S20: When the status information of the other wheels meets a preset condition, at least one wheel is selected from the wheels in the pressure maintaining state to exit the pressure maintaining state according to a preset strategy.

[0054] For example, in order to avoid a dangerous driving situation caused by a plurality of wheels being in a pressure-maintaining state at the same time, when one wheel enters the pressure-maintaining state, at least one other wheel may exit the pressure-maintaining state.

[0055] This embodiment obtains status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state; when the status information of the other wheels meets a preset condition, at least one wheel is selected from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy; based on the ABS active alternating pressure-maintaining strategy, it is possible to avoid, from a control perspective, the situation in which the pressures of four wheels are increased or decreased simultaneously during the operation of the ABS, thereby greatly improving the shaking of the entire vehicle on low-adhesion roads such as ice and snow and improving the user experience.

[0056] Optionally, the at least one wheel includes a target wheel. The target wheel is a wheel that needs to enter a pressure-maintaining state.

[0057] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when it is detected that the adhesion of the target wheel is less than a first threshold, it is determined that the target wheel needs to enter a pressure-maintaining state.

[0058] For example, on a road with medium or low adhesion, in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to enter a pressure-maintaining state. It should be noted that the present application does not limit the value of the first threshold, and a suitable value can be selected as the first threshold for judging the road adhesion state.

[0059] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when the absolute value of the target wheel deceleration is less than a second threshold, it is determined that the target wheel needs to enter a pressure-maintaining state.

[0060] For example, when the absolute value of the deceleration is less than 5m / s^2 on the road surface, in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to enter the pressure holding state. It should be noted that the present application does not limit the numerical value of the second threshold value, and a suitable numerical value can be selected as the second threshold value for determining the absolute value of the deceleration.

[0061] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when a jump condition in which the adhesion increases to a third threshold is not detected, it is determined that the target wheel needs to enter a pressure-maintaining state.

[0062] For example, when the transition from low adhesion to high adhesion is not identified, in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to enter the pressure holding state. It should be noted that the present application does not limit the value of the third threshold, and a suitable value can be selected as the third threshold for judging the road adhesion.

[0063] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when the lateral acceleration of the target wheel is less than a fourth threshold, it is determined that the target wheel needs to enter a pressure-maintaining state.

[0064] For example, when the lateral acceleration of the target wheel is less than a certain value, in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to enter the pressure-maintaining state. It should be noted that the present application does not limit the value of the fourth threshold, and a suitable value can be selected as the fourth threshold for judging the lateral acceleration.

[0065] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when an automatic emergency braking (AEB) function is not activated, it is determined that a target wheel needs to enter a pressure-maintaining state.

[0066] For example, when the automatic emergency brake AEB is not activated, in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to enter the pressure maintaining state.

[0067] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when a hill descent control (HDC) function is not activated, it is determined that a target wheel needs to enter a pressure-maintaining state.

[0068] For example, when functions such as hill descent control (HDC) are not activated, in order to avoid danger to vehicle driving, it can be determined that the target wheel needs to enter a pressure-maintaining state.

[0069] Optionally, before the process of obtaining status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, when the vehicle is in a forward gear, it is determined that the target wheel needs to enter a pressure-maintaining state.

[0070] For example, when the vehicle is in a forward gear, in order to avoid danger in vehicle driving, it can be determined that the target wheel needs to enter a pressure-maintaining state.

[0071] Optionally, in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, before the process of obtaining status information of other wheels, when the current estimated braking hydraulic pressure for the target wheel is greater than at least one compensation threshold value of the locking pressure value, it is determined that the target wheel needs to enter a pressure-maintaining state.

[0072] For example, the current estimated pressure is greater than the locking pressure value by an offset threshold, which can generally be set to about 5 bar. It should be noted that the present application does not limit the value of the compensation threshold value, and a suitable value can be selected as the compensation threshold value for the judgment threshold of the brake hydraulic pressure.

[0073] For example, it can be determined that the target wheel needs to enter the pressure-maintaining state when all of the following conditions are met:

[0074] a. Medium and low adhesion road surface, that is, the absolute value of deceleration is less than 5m / s^2.

[0075] b. The transition condition from low attachment to high attachment is not identified.

[0076] c. The lateral acceleration is less than a certain value.

[0077] d. Functions such as automatic emergency braking AEB and hill descent control HDC are not activated.

[0078] e. The vehicle is in forward gear.

[0079] f. The current estimated pressure is greater than the locking pressure value and decelerates by an offset threshold, which can generally be set to

[0080] About 5bar.

[0081] Optionally, the compensation threshold value includes a basic threshold value and a correction value; and the process of determining the compensation threshold value includes:

[0082] Acquire a current acceleration value of the target wheel, and determine a basic threshold value according to the current acceleration value;

[0083] Acquiring driving condition information, road adhesion information and / or vehicle speed information of the target wheel, and determining a correction value according to the driving condition information, road adhesion information and / or vehicle speed information;

[0084] The compensation threshold value of the target wheel is determined according to the basic threshold value and the correction value.

[0085] For example, the core control strategy of ABS is mainly based on the logic threshold control of slip rate, and the slip rate threshold is equal to the basic threshold plus the correction value. Among them, the basic slip rate threshold is related to acceleration, and the correction value generally refers to different driving conditions, different road surfaces, different vehicle speeds and other conditions.

[0086] Optionally, in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state, in the process of obtaining status information of other wheels, the current road surface on which the target wheel is traveling is judged according to the deceleration value of the target wheel to determine the required pressure-maintaining time of the target wheel.

[0087] For example, different pressure holding times may be set based on different road surfaces, such as low mue, mid mue, split, etc. The judgment of the road surface is mainly based on the magnitude of wheel deceleration.

[0088] Optionally, in the process of responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, the pressure-maintaining state is exited when the pressure-maintaining time of the target wheel reaches a fifth threshold.

[0089] For example, when the pressure-holding time reaches the set value, when it is necessary to exit the pressure-holding state, a wheel can be allowed to exit the pressure-holding state in advance by changing the set time value threshold. In order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to exit the pressure-holding state. It should be noted that this application does not limit the numerical value of the fifth threshold, and a suitable numerical value can be selected as the fifth threshold for judging the pressure-holding time.

[0090] Optionally, in the process of responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, the pressure-maintaining state is exited when a jump condition in which the road adhesion of the target wheel increases to a third threshold is detected.

[0091] For example, when the transition condition from low adhesion to high adhesion has been identified, the pressure can continue to be increased, and in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to exit the pressure holding state. It should be noted that the present application does not limit the value of the third threshold, and a suitable value can be selected as the third threshold for judging the road adhesion.

[0092] Optionally, in the process of responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, the pressure-maintaining state is exited when it is detected that the lateral acceleration value of the target wheel reaches a sixth threshold.

[0093] For example, when the lateral acceleration of the target wheel is greater than a certain value, in order to avoid the danger of vehicle driving, it can be determined that the target wheel needs to exit the pressure-maintaining state. It should be noted that the present application does not limit the value of the sixth threshold, and a suitable value can be selected as the sixth threshold for judging the lateral acceleration.

[0094] Optionally, in the process after responding to at least one wheel of the vehicle needing to enter the pressure holding state, the target wheel exits the pressure holding state when an automatic emergency braking (AEB) function is activated.

[0095] For example, when the automatic emergency braking (AEB) function is activated, in order to ensure the safety and comfort of vehicle driving and avoid vehicle driving dangers, it can be determined that the target wheel can exit the pressure holding state.

[0096] Optionally, in the process after responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, when the hill descent control (HDC) function is activated, the target wheel may exit the pressure-maintaining state:

[0097] For example, when the hill descent control (HDC) function is activated, in order to ensure the safety and comfort of vehicle driving and avoid the danger of vehicle driving, it can be determined that the target wheel can exit the pressure holding state.

[0098] Optionally, in the process after responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, the target wheel exits the pressure-maintaining state when the vehicle is in a non-forward gear.

[0099] For example, when the vehicle is in a non-forward gear, in order to ensure the safety and comfort of the vehicle and avoid the danger of vehicle driving, it can be determined that the target wheel can exit the pressure-maintaining state.

[0100] Optionally, in the process after responding to at least one wheel of the vehicle needing to enter the pressure-maintaining state, the pressure-maintaining state is exited when the slip rate of the target wheel reaches an unstable threshold.

[0101] For example, when the target wheel is in an unstable state, a pressure relief operation may be required. In order to ensure the safety and comfort of vehicle driving and avoid danger to vehicle driving, it can be determined that the target wheel can exit the pressure maintaining state.

[0102] Optionally, the other wheels include a first wheel coaxial with the target wheel. When the status information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, if the first wheel is already in the pressure-maintaining state, the pressure-maintaining time of the first wheel is limited or reduced so that the first wheel exits the pressure-maintaining state earlier than the target wheel.

[0103] For example, when one wheel enters the pressure-holding state first and the other coaxial wheel also enters the pressure-holding state, the pressure-holding time of the wheel that enters the pressure-holding state first is limited or reduced, so that it exits the pressure-holding state in advance, thereby preventing the front or rear of the vehicle from slipping due to insufficient braking force. In order to ensure the safety and comfort of vehicle driving and avoid danger of vehicle driving, the first wheel can be controlled to exit the pressure-holding state before the target wheel.

[0104] Optionally, the other wheels include the second wheel that first enters the pressure-maintaining state. When the state information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, if the target wheel is the last wheel to enter the pressure-maintaining state, the second wheel is controlled to directly exit the pressure-maintaining state.

[0105] For example, when an ordinary four-wheeled vehicle is driving, when the last wheel also enters the pressure holding stage, that is, when all four wheels enter the pressure holding stage, in order to ensure the safety and comfort of the vehicle driving and avoid the danger of vehicle driving, the wheel that entered the pressure holding stage first can be controlled to directly exit the pressure holding stage to prevent insufficient braking force.

[0106] Optionally, the other wheels include a third wheel that has entered a pressure-maintaining state. When the state information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, when the pressure-maintaining time of the third wheel does not reach a seventh threshold value, and the slip rate of the third wheel reaches an unstable threshold, the third wheel is controlled to exit the pressure-maintaining state for pressure relief.

[0107] For example, when the wheel slip rate has reached the unstable threshold before the wheel pressure holding time reaches the set value, in order to ensure the safety and comfort of vehicle driving and avoid the danger of vehicle driving, the pressure holding state is directly exited to enter the pressure release state. It should be noted that the present application does not limit the numerical value of the seventh threshold value, and a suitable value can be selected as the seventh threshold value for judging the slip rate.

[0108] Optionally, the other wheels include a third wheel that has entered a pressure-maintaining state. When the state information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, when the pressure-maintaining time of the third wheel reaches a seventh threshold value and the slip rate of the third wheel does not reach an unstable threshold, the third wheel is controlled to exit the pressure-maintaining state and continue to increase pressure.

[0109] For example, when the pressure holding time reaches the set value, the wheel slip rate has not reached the instability threshold. In order to ensure the safety and comfort of vehicle driving and avoid danger to vehicle driving, the pressure is continued to be increased until the wheel becomes unstable and then exits the pressure holding state to enter the pressure relief state.

[0110] Second embodiment

[0111] The present application also provides a vehicle, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the vehicle control method as described above are implemented.

[0112] Figure 2 Schematic diagram of control logic for active pressure maintenance of a target vehicle in one embodiment of the present application. Figure 3 Schematic diagram of vehicle speed and wheel speed control for active pressure maintenance of a target vehicle in one embodiment of the present application.

[0113] Please also refer to Figure 2 and Figure 3 As shown, in one embodiment, in order to improve the vehicle shaking problem caused by the simultaneous increase and decrease of wheel-end pressure, a new active alternating pressure-maintaining strategy is added during the ABS boost phase, that is, the wheels are pressure-maintained for a certain period of time in advance near the ABS locking point; each wheel enters the pressure-maintaining stage in advance according to this strategy, but after the wheel on the other side also enters the pressure-maintaining stage, the pressure-maintaining time of the wheel that enters the pressure-maintaining stage first is limited or reduced; when all four wheels enter this pressure-maintaining logic, the wheel that enters the pressure-maintaining stage first directly exits the pressure-maintaining stage. The purpose is to avoid increasing or decreasing the pressure of the four wheels at the same time and to ensure sufficient braking force as much as possible.

[0114] In one embodiment, the control strategy of the vehicle is as follows:

[0115] 1. Entry conditions (all conditions must be met):

[0116] Medium and low adhesion road surface, that is, the absolute value of deceleration is less than 5m / s^2.

[0117] The transition from low attachment to high attachment is not recognized.

[0118] The lateral acceleration is less than a certain value.

[0119] Functions such as automatic emergency braking (AEB) and hill descent control (HDC) are not activated.

[0120] The vehicle is in a forward gear.

[0121] The current estimated pressure is greater than the locking pressure value and decelerates by an offset threshold, which can generally be set to around 5 bar.

[0122] 2. Exit conditions (any condition is met):

[0123] a. The pressure holding time reaches the set value (by changing the set value threshold, a certain wheel can exit the pressure holding in advance).

[0124] b. The transition from low adhesion to high adhesion is identified because this condition requires a rapid increase in braking force and avoids pressure maintenance as much as possible.

[0125] c. The lateral acceleration is greater than a certain value.

[0126] d. Functions such as automatic emergency braking AEB and hill descent control HDC are activated.

[0127] e. The vehicle is in a non-forward gear.

[0128] f. The wheel is in an unstable state and needs to be depressurized.

[0129] 3. Key Controls

[0130] a. Set different holding times based on different road surfaces, such as low mue, mid mue, split, etc. The road surface judgment is mainly based on the size of the deceleration.

[0131] b. When the pressure holding time reaches the set value and the wheel slip rate has not reached the unstable threshold, the pressure will continue to be increased until the wheel becomes unstable and enters the pressure relief state.

[0132] c. If the wheel slip rate reaches the unstable threshold before the pressure holding time reaches the set value, the pressure will be released directly.

[0133] d. When one wheel enters the pressure holding stage first and the other coaxial wheel also enters the pressure holding stage, limit or reduce the pressure holding time of the wheel that enters the pressure holding stage first, so that it exits the pressure holding stage in advance to prevent insufficient braking force.

[0134] e. When the last wheel also enters the pressure-holding state, that is, when all four wheels enter the pressure-holding state, the wheel that enters the pressure-holding state first will directly exit the pressure-holding state to prevent insufficient braking force.

[0135] In this embodiment, based on the ABS active alternating pressure maintaining strategy of the present application, the situation where the pressure increases and decreases on the four wheels at the same time during the ABS process can be avoided to the greatest extent possible from a control perspective, thereby greatly improving the shaking of the entire vehicle on low-adhesion roads such as ice and snow and improving customer satisfaction.

[0136] The vehicle control method and vehicle of the present application obtain status information of other wheels in response to at least one wheel of the vehicle needing to enter a pressure-maintaining state; when the status information of the other wheels meets a preset condition, at least one wheel is selected from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy; based on the ABS active alternating pressure-maintaining strategy, it is possible to avoid, from a control perspective, the situation in which the four wheels increase or decrease pressure at the same time during the operation of the ABS, thereby greatly improving the shaking of the entire vehicle on low-adhesion roads such as ice and snow and improving the user experience.

[0137] It is understood that the above scenarios are only examples and do not constitute a limitation on the application scenarios of the technical solutions provided in the embodiments of the present application. The technical solutions of the present application can also be applied to other scenarios. For example, it is known to those skilled in the art that with the evolution of the system architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0138] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0139] The steps in the method of the embodiment of the present application can be adjusted in order, combined and deleted according to actual needs.

[0140] The units in the device of the embodiment of the present application can be merged, divided and deleted according to actual needs.

[0141] In the present application, the same or similar terminology concepts, technical solutions and / or application scenario descriptions are generally described in detail only the first time they appear. When they appear again later, they are generally not repeated for the sake of brevity. When understanding the technical solutions and other contents of the present application, for the same or similar terminology concepts, technical solutions and / or application scenario descriptions that are not described in detail later, reference can be made to the previous related detailed descriptions.

[0142] In the present application, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0143] The various technical features of the technical solution of the present application can be arbitrarily combined. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of the present application.

[0144] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A vehicle control method, characterized in that: include: In response to a wheel of the vehicle needing to enter a pressure-maintaining state, obtaining state information of other wheels, wherein the target wheel is the wheel that needs to enter a pressure-maintaining state; When the state information of the other wheels meets the preset conditions, selecting at least one wheel from the wheels in the pressure maintaining state to exit the pressure maintaining state according to the preset strategy; The other wheels include a first wheel coaxial with the target wheel; when the state information of the other wheels meets a preset condition, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, if the first wheel is already in the pressure-maintaining state, limiting or reducing the pressure-maintaining time of the first wheel so that the first wheel exits the pressure-maintaining state earlier than the target wheel; and / or, The other wheels include the second wheel that first enters the pressure-maintaining state; when the state information of the other wheels meets the preset conditions, in the process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to the preset strategy, if the target wheel is the last wheel to enter the pressure-maintaining state, the second wheel is controlled to directly exit the pressure-maintaining state.

2. A vehicle control method according to claim 1, characterized in that: In the process of responding to a wheel of the vehicle needing to enter a pressure-maintaining state and before obtaining the state information of other wheels, when the driving condition of the target wheel meets at least one of the following, it is determined that the target wheel needs to enter a pressure-maintaining state: detecting that the adhesion of the road surface on which the target wheel is traveling is less than a first threshold; The absolute value of the target wheel deceleration is less than a second threshold; A jump condition in which the adhesion increases to a third threshold value is not detected; The lateral acceleration of the target wheel is less than a fourth threshold; The automatic emergency braking (AEB) function is not activated; The Hill Descent Control (HDC) function is not activated; The vehicle is in forward gear; The currently estimated brake fluid pressure of the target wheel is greater than the locking pressure value by at least one compensation threshold value.

3. A vehicle control method as claimed in claim 2, characterized in that: The compensation threshold value includes a basic threshold value and a correction value; and the process of determining the compensation threshold value includes: Acquire a current acceleration value of the target wheel, and determine a basic threshold value according to the current acceleration value; Acquiring driving condition information, road adhesion information and / or vehicle speed information of the target wheel, and determining a correction value according to the driving condition information, road adhesion information and / or vehicle speed information; The compensation threshold value of the target wheel is determined according to the basic threshold value and the correction value.

4. A vehicle control method as claimed in claim 2, characterized in that: In the process of obtaining status information of other wheels in response to a wheel of the vehicle needing to enter a pressure-maintaining state, the current road surface on which the target wheel is traveling is judged according to the deceleration value of the target wheel to determine the required pressure-maintaining time of the target wheel.

5. A vehicle control method as claimed in claim 2, characterized in that: In the process after responding to a wheel of the vehicle needing to enter the pressure-maintaining state, the target wheel exits the pressure-maintaining state when at least one of the following conditions is met: The pressure holding time reaches a fifth threshold; detecting a jump condition in which the adhesion increases to a third threshold; detecting that the lateral acceleration value of the target wheel reaches a sixth threshold; The Autonomous Emergency Braking (AEB) feature is activated; Hill Descent Control (HDC) function activated; The vehicle is in a non-forward gear; The slip rate of the target wheel reaches an unstable threshold.

6. A vehicle control method according to any one of claims 1 to 5, characterized in that: The other wheels include a third wheel that has entered a pressure-maintaining state; when the state information of the other wheels meets a preset condition, in a process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, when the pressure-maintaining time of the third wheel does not reach a seventh threshold value, and the slip rate of the third wheel reaches an unstable threshold, the third wheel is controlled to exit the pressure-maintaining state for pressure relief.

7. A vehicle control method as claimed in claim 6, characterized in that: The other wheels include a third wheel that has entered a pressure-maintaining state; when the state information of the other wheels meets a preset condition, in a process of selecting at least one wheel from the wheels in the pressure-maintaining state to exit the pressure-maintaining state according to a preset strategy, when the pressure-maintaining time of the third wheel reaches a seventh threshold and the slip rate of the third wheel has not reached an unstable threshold, the third wheel is controlled to exit the pressure-maintaining state and continue to increase pressure.

8. A vehicle, characterized in that: include: A memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the vehicle control method according to any one of claims 1 to 7 are implemented.

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