CN118790207A

CN118790207A - Vehicle control method and device and vehicle

Info

Publication number: CN118790207A
Application number: CN202411274694.8A
Authority: CN
Inventors: 林智能; 张洋; 居婷; 饶宇衡; 杨慧; 黄大飞
Original assignee: Chengdu Seres Technology Co Ltd
Current assignee: Chengdu Seres Technology Co Ltd
Priority date: 2024-09-12
Filing date: 2024-09-12
Publication date: 2024-10-18

Abstract

The application relates to a vehicle control method and device and a vehicle. The method comprises the following steps: acquiring the current wheel speed of a wheel in a target vehicle under the current braking action, the current piston pressure of a braking piston and the current pedal stroke of a braking pedal; determining a current friction coefficient of a friction brake in the target vehicle according to the current wheel speed and the current piston pressure; determining a target braking strength of a brake pedal in a target vehicle according to the current friction coefficient and the current pedal travel under the condition that the current friction coefficient meets a braking force attenuation condition; and performing brake control on the target vehicle according to the target brake intensity. By adopting the method, the accuracy of the brake control of the target vehicle can be improved.

Description

Vehicle control method and device and vehicle

Technical Field

The present application relates to the field of vehicle control technologies, and in particular, to a vehicle control method and apparatus, and a vehicle.

Background

As vehicles are evolving towards motorization, intellectualization, the brake pedal of vehicles has driven the transformation and upgrading of vehicles by virtue of its level of universalization, integration and drive-by-wire. In the implementation of current brake-by-wire dry braking schemes, in order for the driver to have the same brake feel as conventional brake systems, a brake pedal simulator is also typically provided in the brake-by-wire system to ensure that the driver is able to accurately grasp the intensity of the brake applied to the pedal to effect control of the vehicle.

However, the pedal simulator design recognizes the braking intention depending on only the pedal stroke, and does not provide a master cylinder pressure feedback mechanism, such as a conventional wet hydraulic brake system, to transmit the braking reaction force to the driver. And the current full-decoupling hydraulic control system is centered on minimizing feedback perception of hydraulic pressure by a user, so that consistent foot feeling experience of braking force control is ensured. However, when the braking system is attenuated, the driver cannot timely sense the braking system, and the driver continues to drive violently until the braking system fails, so that potential safety hazards are caused.

Disclosure of Invention

In view of the foregoing, it is desirable to provide a vehicle control method and apparatus, and a vehicle that can accurately control a braking process of the vehicle.

In a first aspect, the present application provides a vehicle control method including:

Acquiring the current wheel speed of a wheel in a target vehicle under the current braking action, the current piston pressure of a braking piston and the current pedal stroke of a braking pedal;

determining a current coefficient of friction of a friction brake in the target vehicle based on the current wheel speed and the current piston pressure;

determining a target brake strength of a brake pedal in the target vehicle according to the current friction coefficient and the current pedal travel under the condition that the current friction coefficient meets a brake force attenuation condition;

and according to the target braking intensity, performing braking control on the target vehicle.

In one embodiment, the determining the target brake strength of the brake pedal in the target vehicle according to the current friction coefficient and the current pedal stroke includes: determining a reference brake strength of the brake pedal under a current pedal stroke; determining a current fade compensation coefficient of the brake pedal according to the current friction coefficient and the current pedal travel; and determining the target braking intensity of the brake pedal according to the product of the current fading compensation coefficient and the reference braking intensity.

In one embodiment, the determining the current fade compensation coefficient of the brake pedal according to the current friction coefficient and the current pedal stroke includes: determining a current brake weakness of the brake pedal at a current coefficient of friction; and based on a preset exponential function, according to a first preset smoothing coefficient, carrying out exponential decay on the difference between the current pedal stroke and the current braking weakening degree, and determining a current decay compensation coefficient.

In one embodiment, according to the target braking intensity, braking control is performed on the target vehicle, including: determining a first offset compensation strength of the brake pedal according to the current brake weakness, the current pedal stroke and a maximum pedal stroke of the brake pedal; accumulating the first offset compensation intensity over the target brake intensity to update the target brake intensity; and according to the updated target braking intensity, performing braking control on the target vehicle.

In one embodiment, determining a first offset compensation strength of the brake pedal based on the current brake fade, the current pedal travel, and a maximum pedal travel of the brake pedal comprises: based on the preset exponential function, carrying out exponential decay on the difference value between the current pedal stroke and the maximum pedal stroke according to a second preset smoothing coefficient, and determining a first basic compensation intensity; wherein the second preset smoothing coefficient is 1; based on the preset exponential function, according to the first preset smoothing coefficient, carrying out exponential decay on the difference between the maximum pedal stroke and the current braking weakening degree to obtain an offset compensation coefficient; a first offset compensation intensity of the brake pedal is determined based on a product of the offset compensation coefficient and the first base compensation intensity.

In one embodiment, according to the target braking intensity, braking control is performed on the target vehicle, including: determining a second offset compensation strength of the brake pedal based on the maximum pedal travel, the current brake weakness, and a minimum pedal travel of the brake pedal; reducing the second offset compensation intensity on the target brake intensity to update the target brake intensity; and according to the updated target braking intensity, performing braking control on the target vehicle.

In one embodiment, determining a second offset compensation strength of the brake pedal based on the maximum pedal travel, the current brake fade, and a minimum pedal travel of the brake pedal comprises: based on the preset exponential function, according to the second preset smoothing coefficient, carrying out exponential decay on the difference value between the minimum pedal stroke and the maximum pedal stroke, and determining a second basic compensation intensity; based on the preset exponential function, according to the first preset smoothing coefficient, carrying out exponential decay on the difference between the maximum pedal stroke and the current braking weakening degree to obtain an offset compensation coefficient; and determining a second offset compensation intensity of the brake pedal according to the product of the offset compensation coefficient and the second basic compensation intensity.

In one embodiment, determining a current brake fade of the brake pedal at a current coefficient of friction comprises: determining a first brake weakness of the brake pedal at a current coefficient of friction; if the current braking behavior is a first braking behavior, selecting the smaller value of the first braking weakening degree and a default instantaneous braking weakening degree as the current braking weakening degree of the brake pedal; if the current braking behavior is a non-first braking behavior, determining the instantaneous braking weakening degree of the current braking behavior according to the instantaneous braking weakening degree corresponding to the previous braking behavior of the current braking behavior, the historical pedal travel of the previous braking behavior and the braking interval between the current braking behavior and the previous braking behavior, and selecting the smaller value of the instantaneous braking weakening degree of the current braking behavior and the first braking weakening degree as the current braking weakening degree of the brake pedal.

In one embodiment, determining the instantaneous brake weakness of the current brake behavior according to the instantaneous brake weakness corresponding to the previous brake behavior of the current brake behavior, the historical pedal travel of the previous brake behavior, and the brake interval between the current brake behavior and the previous brake behavior includes: determining an instantaneous braking weakening amplitude according to the product of the historical pedal travel of the previous braking action and a preset stepping amplitude; determining an instantaneous braking compensation amplitude according to the product of the braking interval and a preset compensation amplitude; and determining the instantaneous braking weakening degree of the current braking action according to the instantaneous braking weakening degree, the instantaneous braking weakening degree and the instantaneous braking compensation degree corresponding to the previous braking action.

In one embodiment, determining the instantaneous brake weakness of the current brake behavior according to the instantaneous brake weakness corresponding to the previous brake behavior, the instantaneous brake weakness and the instantaneous brake compensation amplitude includes: selecting a larger value of the target difference value and the default brake weakening degree as a second brake weakening degree; the target difference value is the difference value between the instantaneous braking weakening degree corresponding to the previous braking action and the instantaneous braking weakening amplitude; and taking the sum value between the second braking weakening degree and the instantaneous braking compensation amplitude as the instantaneous braking weakening degree of the current braking action.

In a second aspect, the present application also provides a vehicle control apparatus including:

the information acquisition module is used for acquiring the current wheel speed of the wheels in the target vehicle, the current piston pressure of the brake piston and the current pedal stroke of the brake pedal under the current braking action;

The coefficient determining module is used for determining the current friction coefficient of the friction braking piece in the target vehicle according to the current wheel speed and the current piston pressure;

the intensity determining module is used for determining target braking intensity of a brake pedal in the target vehicle according to the current friction coefficient and the current pedal stroke under the condition that the current friction coefficient meets a braking force attenuation condition;

and the brake control module is used for carrying out brake control on the target vehicle according to the target brake intensity.

In a third aspect, the present application also provides a computer device comprising a memory and a processor, the memory storing a computer program, the processor implementing the following steps when executing the computer program:

In a fourth aspect, the present application also provides a computer readable storage medium having stored thereon a computer program which when executed by a processor performs the steps of:

In a fifth aspect, the application also provides a computer program product comprising a computer program which, when executed by a processor, performs the steps of:

In a sixth aspect, the application also provides a vehicle provided with means for carrying out the method steps of:

According to the vehicle control method, the vehicle control device and the vehicle, after the current wheel speed of the wheels in the target vehicle, the current piston pressure of the brake piston and the current pedal travel of the brake pedal under the current braking action are obtained, the current friction coefficient of the friction brake piece in the target vehicle is determined according to the current wheel speed and the current piston pressure; further, in the case where the current friction coefficient satisfies the braking force attenuation condition, a target braking intensity of a brake pedal in the target vehicle is determined according to the current friction coefficient and the current pedal stroke, and braking control is performed on the target vehicle according to the target braking intensity. According to the scheme, whether the target vehicle enters a braking force attenuation state or not is accurately detected by introducing the current friction coefficient and according to the friction coefficient; under the condition that the target vehicle is determined to enter a braking force attenuation state, the perception of weakening the braking performance is realized according to the current friction coefficient and the current pedal stroke, and the braking strength of the target vehicle in the braking force attenuation state is accurately simulated; in addition, the time efficiency and the accuracy of the determined target braking intensity are ensured because the current wheel speed, the current piston pressure and the current pedal stroke are data acquired in real time, so that the braking process of the target vehicle is effectively and accurately controlled.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the related art, the drawings that are needed in the description of the embodiments of the present application or the related technologies will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and other related drawings may be obtained according to these drawings without inventive effort to those of ordinary skill in the art.

FIG. 1 is a diagram of an application environment for a vehicle control method in one embodiment;

FIG. 2 is a flow chart of a method of controlling a vehicle in one embodiment;

FIG. 3 is a graph of the coefficient of friction of a friction brake as a function of temperature of a brake material in one embodiment;

FIG. 4 is a graph showing brake strength versus braking travel for various brake weakness levels in one embodiment;

FIG. 5 is a graphical representation of the braking strength versus pedal travel for one embodiment of the present application versus the prior art;

FIG. 6 is a flow chart of a method of controlling a vehicle in another embodiment;

FIG. 7 is a block diagram showing the construction of a vehicle control apparatus in one embodiment;

fig. 8 is an internal structural diagram of a computer device in one embodiment.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

The vehicle control method provided by the embodiment of the application can be applied to an application environment shown in fig. 1. Wherein the brake system 110 is a system for controlling a vehicle speed in a target vehicle, and the drive-by-wire chassis angle controller 120 is a device for monitoring and controlling an operation state of the target vehicle by an electric signal in the target vehicle. Optionally, the brake system 110 obtains a current wheel speed of wheels in the target vehicle, a current piston pressure of the brake piston, and a current pedal travel of the brake pedal under a current braking action monitored by the brake-by-wire chassis angle controller 120; determining the current friction coefficient of a friction braking piece in the target vehicle according to the current wheel speed and the current piston pressure; further, in the case where the current friction coefficient satisfies the braking force attenuation condition, determining a target braking strength of a brake pedal in the target vehicle according to the current friction coefficient and the current pedal travel; and performing brake control on the target vehicle according to the target brake intensity.

In one embodiment, as shown in fig. 2, a vehicle control method is provided, and the method is applied to the braking system 110 in fig. 1, for example, and specifically includes the following steps:

S210, acquiring the current wheel speed of wheels in the target vehicle under the current braking action, the current piston pressure of a brake piston and the current pedal stroke of a brake pedal.

Wherein the braking behavior is one of controlling the speed of the vehicle by stepping on a brake pedal; the current braking behavior refers to braking behavior generated by the driving user of the target vehicle at the current stepping time. The current wheel speed is the rotation speed of the wheels of the target vehicle at the current pedaling time; the brake piston is a device for increasing the braking force and ‌ improving the stability and smoothness of braking in a target vehicle; the current piston pressure is the pressure born by the brake piston at the current stepping time; the brake pedal is a pedal for limiting the speed of the target vehicle, namely a brake plate; the current pedal stroke is the stroke of the brake pedal moving down at the current stepping time.

Alternatively, when a driver user of the target vehicle has a need to control deceleration of the target vehicle, the driver may control deceleration of the target vehicle by depressing a brake pedal in the target vehicle; at this time, the target vehicle recognizes the current braking behavior of the driving user. Further, under the current braking action, vehicle state data such as the current wheel speed of wheels, the current piston pressure of a braking piston, the current pedal stroke of a braking pedal and the like of the target vehicle monitored in real time by the drive-by-wire chassis angle controller are obtained.

It should be noted that, in the embodiment of the present application, the stroke range of the pedal stroke may be 0% -100%, or may be a numerical range corresponding to 0% -100%, for example, 0-10, where scaling is performed. That is, the pedal travel may be presented as a percentage or as a number.

S220, determining the current friction coefficient of the friction braking element in the target vehicle according to the current wheel speed and the current piston pressure.

The friction brake is a member for decelerating the target vehicle, and may include, for example, at least one of a brake disc, a brake drum, and the like, and the present application is not limited in any way. The current friction coefficient is the friction coefficient of the friction braking piece in the target vehicle at the current stepping time.

Optionally, in consideration of factors involved in actual calculation of the friction coefficient, in the embodiment of the present application, the friction coefficient may be estimated directly according to the wheel speed and the piston pressure. That is, the current friction coefficient of the friction brake in the target vehicle may be calculated from the current wheel speed and the current piston pressure. Specifically, the current friction coefficient can be expressed by the following formula (1):

（1）

Wherein, Is the current friction coefficient; the simplified preset fixed coefficient can be determined through experiments; Is the current piston pressure; Is the current wheel speed.

For example, for each wheel of the target vehicle, the current friction coefficient of that wheel may be determined according to formula (1), and the current friction coefficient of the target vehicle may be determined based on the statistics of the current friction coefficients of the wheels. The statistical result may be an average value, a next largest value, a preset quantile, or the like, which is not limited in the present application.

S230, determining the target braking strength of the brake pedal in the target vehicle according to the current friction coefficient and the current pedal stroke when the current friction coefficient meets the braking force attenuation condition.

The braking force attenuation condition is a condition that needs to be satisfied for braking performance to be reduced. The target brake strength characterizes the braking capacity of the brake pedal.

It will be appreciated that the brake material in the target vehicle may maintain a desired performance at the set temperature, but if the temperature of the brake material is not within the set temperature range, the performance of the brake material will be degraded and unstable. In this case, the friction coefficient of the friction brake member is lowered, resulting in a decrease in braking performance. A curve of the friction coefficient of the friction brake in the target vehicle as shown in fig. 3 varies with the temperature of the brake material. When the temperature of the brake material is too small or too large (i.e., not within the set temperature range), the coefficient of friction is below a predetermined threshold. Therefore, it is possible to determine whether the target vehicle needs to enter a state of braking force attenuation, based on the relationship between the friction coefficient and the threshold value set in advance.

Optionally, if the current friction coefficient is lower than a preset friction coefficient threshold value, the current friction coefficient is indicated to meet the braking force attenuation condition. At this time, it is necessary to combine the actual operation law of the target vehicle in the braking force attenuation state, and according to the current friction coefficient and the current pedal travel, perform attenuation simulation on the braking strength of the brake pedal in the target vehicle, and obtain the target braking strength of the brake pedal in the target vehicle. If the current friction coefficient is not lower than the preset friction coefficient threshold value, the target braking strength of the brake pedal in the target vehicle can be determined in a traditional mode directly according to the product of the current pedal stroke and the preset coefficient.

Notably, with continued reference to FIG. 3, when the coefficient of friction of the friction brake of the target vehicle exceeds a threshold, the target vehicle's brake system has failed to provide sufficient braking force for safe driving of the entire vehicle. In this case, an early warning is sent to the driver to prompt the driver that the target vehicle needs to enter a degraded running mechanism, so as to guide the driver to take necessary intervention measures in time, such as reducing the vehicle speed or stopping alongside.

S240, performing braking control on the target vehicle according to the target braking intensity.

After the current wheel speed of the wheels in the target vehicle, the current piston pressure of the brake piston and the current pedal travel of the brake pedal under the current braking action are obtained, determining the current friction coefficient of a friction brake piece in the target vehicle according to the current wheel speed and the current piston pressure; further, in the case where the current friction coefficient satisfies the braking force attenuation condition, a target braking intensity of a brake pedal in the target vehicle is determined according to the current friction coefficient and the current pedal stroke, and braking control is performed on the target vehicle according to the target braking intensity. According to the scheme, whether the target vehicle enters a braking force attenuation state or not is accurately detected by introducing the current friction coefficient and according to the friction coefficient; under the condition that the target vehicle is determined to enter a braking force attenuation state, the perception of weakening the braking performance is realized according to the current friction coefficient and the current pedal stroke, and the braking strength of the target vehicle in the braking force attenuation state is accurately simulated; in addition, the time efficiency and the accuracy of the determined target braking intensity are ensured because the current wheel speed, the current piston pressure and the current pedal stroke are data acquired in real time, so that the braking process of the target vehicle is effectively and accurately controlled.

On the basis of the technical solutions of the foregoing embodiments, in order to ensure the accuracy of the determined target braking strength, the present application further provides an alternative embodiment, in which the step of determining the target braking strength in S230 is refined, where the step includes:

s410, determining the reference braking strength of the brake pedal under the current pedal stroke.

The reference brake strength is used for representing the pedal strength corresponding to a brake pedal in a target vehicle determined in a traditional mode, and a driver cannot feel foot feedback of any piston force at the moment.

For example, a reference brake strength of the brake pedal at the current pedal stroke may be determined based on a product of the current pedal stroke and a first preset coefficient.

The first predetermined coefficient is understood to be a map coefficient between the current pedal travel and a reference brake strength, by means of which the current pedal travel can be converted into the brake strength of the brake pedal. It should be noted that the first preset coefficients corresponding to different current pedal strokes may be the same or different, and may be determined through a plurality of experiments, which is not limited in any way by the present application.

Specifically, the reference brake strength can be expressed by the following formula (2):

（2）

Wherein, Is the reference braking strength; the first preset coefficient; is the current pedal travel.

S420, determining the current decline compensation coefficient of the brake pedal according to the current friction coefficient and the current pedal stroke.

The current fading compensation coefficient is a coefficient which needs to perform fading compensation on the reference braking intensity.

Optionally, in order to make the driver and the user obviously feel that the front-end travel control of the braking intensity of the target vehicle braking system is weak, and meanwhile, the required braking force is increased, in the embodiment of the application, an exponential function is adopted to simulate the braking force decline process of a brake pedal. Specifically, the current fading compensation coefficient constructed by the exponential function model can be represented by the following formula (3):

（3）

Wherein, Compensating the coefficient for the current decline; Is the current friction coefficient; Representing a function related to the current pedal travel and the current coefficient of friction.

Further, to ensure the accuracy and rationality of the determined current fade compensation coefficient, a parameter of brake fade may be introduced to numerically quantify the degree of brake pedal feel required to be fade.

Alternatively, the current brake weakness of the brake pedal at the current friction coefficient may be determined taking into account that the brake weakness is proportional to the friction coefficient; based on a preset exponential function, according to a first preset smoothing coefficient, carrying out exponential decay on the difference between the current pedal stroke and the current braking weakening degree, and determining a current decay compensation coefficient. The preset exponential function is a preset exponential function used for simulating a braking force decline process of the brake pedal.

For example, the current brake fade of the brake pedal at the current friction coefficient may be determined based on the product of the current friction coefficient and the second preset coefficient.

The current brake weakening degree is used for representing a quantized degree value when a driving user perceives feedback of foot feeling of the piston force through weakening the reference brake strength. The second preset coefficient is understood to be a mapping coefficient between the current friction coefficient and the current brake weakening, by means of which the current friction coefficient can be converted into the current brake weakening when weakening the brake strength of the brake pedal. It should be noted that the second preset coefficients corresponding to different current friction coefficients may be the same or different, and may be determined by a plurality of experiments, which is not limited in the present application. It should be noted that the second preset coefficient is independent of the first preset coefficient.

Thus, the current brake fade degree can be expressed by the following equation (4):

（4）

Wherein, Is the current brake weakening; Is a second preset coefficient.

Further, in the above formula (3)This can be expressed by the following formula (5):

（5）

Wherein, The first preset smoothing coefficient is a positive number not greater than 1, and is used for representing the attenuation degree corresponding to the exponential attenuation process, and the specific value of the first preset smoothing coefficient can be set empirically or determined through a plurality of experiments, so that the application is not limited in any way. In one specific implementation, the first preset smoothing factor may be 0.5.

Finally, in combination with the above equation (3) and equation (5), the current fading compensation coefficient can be expressed by the following equation (6):

（6）

S430, determining the target braking intensity of the brake pedal according to the product of the current fading compensation coefficient and the reference braking intensity.

The target braking strength is the result of braking force decline of the reference braking strength of the brake pedal, so that the aim of enabling a driving user to sense the feedback of the foot feeling of the piston force is fulfilled.

Alternatively, the product of the current fade compensation coefficient and the reference brake strength may be directly used as the target brake strength of the brake pedal. Specifically, the target brake strength of the brake pedal can be expressed by the following formula (7):

（7）

Wherein, Indicating a target brake strength of the brake pedal.

According to the embodiment of the application, the current fading compensation coefficient of the brake pedal is introduced according to the current friction coefficient and the current pedal stroke, and the fading compensation is carried out on the reference brake strength according to the current fading compensation coefficient on the existing reference brake strength, so that the target brake strength of the target vehicle in a brake force fading state is accurately simulated.

On the basis of the technical solutions of the foregoing embodiments, in order to achieve accurate braking control of a target vehicle, the present application further provides an alternative embodiment, in which the braking control step in S240 is refined, where the step includes:

S510, determining a first offset compensation intensity of the brake pedal according to the current brake weakening degree, the current pedal stroke and the maximum pedal stroke of the brake pedal.

Wherein the first offset compensation strength is used for compensating the braking strength value when the braking pedal reaches 100% stroke.

Optionally, in the embodiment of the present application, an exponential function model is introduced to simulate the braking force decay process of the brake pedal, but since the exponential function cannot reach infinity, the original braking strength value (i.e. the reference braking strength) cannot be fully reached when the brake pedal reaches 100% of the stroke. Therefore, a first offset compensation strength of the brake pedal needs to be introduced to compensate the brake pedal.

Alternatively, the actual braking strength of the brake pedal when the braking pedal reaches 100% of the stroke can be comprehensively considered, the calculating mode of the first offset compensation strength is deduced by combining the characteristics of the exponential function model, and further, the first offset compensation strength of the brake pedal is determined according to the current braking weakening degree, the current pedal stroke and the maximum pedal stroke of the brake pedal based on the calculating mode of the first offset compensation strength.

S520, accumulating the first offset compensation intensity on the target braking intensity to update the target braking intensity.

Optionally, in order to compensate the target braking strength, the first offset compensation strength is accumulated on the basis of the target braking strength, and the target braking strength is updated to obtain the updated target braking strength. Specifically, on the basis of the above formula (7), the first offset compensation intensity is accumulated to obtain the updated target braking intensity, which can be specifically shown by the following formula (8):

（8）

Wherein, The updated target braking strength; the intensity is compensated for the first offset.

And S530, performing braking control on the target vehicle according to the updated target braking intensity.

Optionally, according to the updated target braking intensity, replacing the target braking intensity before updating, and performing braking control on the target vehicle.

According to the embodiment of the application, the first offset compensation intensity of the brake pedal is introduced according to the current brake weakening degree, the current pedal stroke and the maximum pedal stroke of the brake pedal, and the target brake intensity is compensated according to the first offset compensation intensity, so that the brake intensity of the target vehicle can be accurately simulated when the brake pedal reaches 100% of the stroke, and the accurate brake control of the target vehicle is further realized.

On the basis of the technical solutions of the foregoing embodiments, in order to ensure the accuracy of the determined first offset compensation, the present application further provides an alternative embodiment, in which the step of determining the first offset compensation strength in S510 is refined, where the step includes:

and S610, carrying out exponential decay on the difference between the current pedal stroke and the maximum pedal stroke according to a second preset smoothing coefficient based on a preset exponential function, and determining the first basic compensation intensity.

The second preset smoothing coefficient is used for representing the attenuation degree corresponding to the maximum attenuation in the exponential attenuation process; the second preset smoothing coefficient may be 1, or any value that fluctuates around 1, and the specific fluctuation range may be determined empirically, or may be determined through a large number of experiments. It will be appreciated that by providing a maximum degree of exponential decay in the difference between the current pedal stroke and the maximum pedal stroke, a relatively fixed first base compensation strength can be obtained.

Optionally, the process of determining the first base compensation strength by exponentially attenuating the difference between the current pedal stroke and the maximum pedal stroke according to a second preset smoothing coefficient based on a preset exponential function may be represented by the following formula (9):

（9）

Wherein, Compensating the intensity for the first basis; a second preset smoothing coefficient; Is the current pedal travel; Is the maximum pedal travel. When the following is performed When the above formula (9) is adoptedMay not participate in the calculation process.

S620, based on a preset exponential function, according to a first preset smoothing coefficient, carrying out exponential decay on the difference between the maximum pedal stroke and the current braking weakening degree to obtain an offset compensation coefficient.

The offset compensation coefficient is used for representing the compensation degree when offset compensation is carried out on the target braking strength under 100% of travel on the basis of the first basic compensation strength.

Optionally, based on a preset exponential function, according to a first preset smoothing coefficient, the process of exponentially attenuating the difference between the maximum pedal stroke and the current brake weakening degree to obtain the offset compensation coefficient may be represented by the following formula (10):

（10）

Wherein, Is an offset compensation coefficient; A first preset smoothing coefficient; Is the maximum pedal travel; indicating the current brake fade.

S630, determining the first offset compensation intensity of the brake pedal according to the product of the offset compensation coefficient and the first basic compensation intensity.

Optionally, in order to ensure accuracy of the first offset compensation strength, a first preset coefficient is introduced to optimize on the basis of the offset compensation coefficient. Further, the first offset compensation intensity of the brake pedal according to the product of the offset compensation coefficient and the first base compensation intensity can be expressed by the following formula (11):

（11）

Wherein, Representing a first preset coefficient.

According to the embodiment of the application, the actual state of the target vehicle is fully considered by introducing the offset compensation coefficient and the first basic compensation strength, so that the accuracy of the first offset compensation strength of the brake pedal is ensured according to the product of the offset compensation coefficient and the first basic compensation strength.

On the basis of the technical solutions of the foregoing embodiments, in order to further improve the accuracy of the braking process, the present application further provides an alternative embodiment, in which the braking control step in S240 is refined, where the step includes:

S710, determining a second offset compensation intensity of the brake pedal according to the maximum pedal stroke, the current brake weakening degree and the minimum pedal stroke of the brake pedal.

Wherein the second offset compensation strength is used for compensating the braking strength value of the braking pedal at 0% stroke.

Alternatively, and with the same considerations, the exponential function introduced cannot reach infinity, and in the starting position (i.e. when the brake pedal is at 0% stroke), to ensure that the actual output braking intensity should also be 0 when the braking force demand is 0%, a second offset compensation intensity needs to be introduced for compensation. Further, the difference between the minimum pedal stroke and the maximum pedal stroke may be exponentially attenuated according to a second preset smoothing coefficient based on a preset exponential function, to determine a second basic compensation strength; a second offset compensation intensity of the brake pedal is determined based on a product of the offset compensation coefficient and the second base compensation intensity.

The second preset smoothing coefficient may be 1, which is used to represent the attenuation degree corresponding to the maximum attenuation in the exponential attenuation process. It will be appreciated that by providing a maximum degree of exponential decay in the difference between the minimum pedal travel and the maximum pedal travel, a relatively fixed second base compensation strength can be obtained.

Specifically, the second base compensation strength of the brake pedal can be expressed by the following formula (12):

（12）

Wherein, Compensating the intensity for a second basis; a second preset smoothing coefficient; Is the minimum pedal travel; Is the maximum pedal travel.

On the basis of the above-described formula (12) and formula (10), a second offset compensation strength of the brake pedal can be obtained as shown in the following formula (13):

（13）

Wherein, The intensity is compensated for the second offset.

S720, reducing the second offset compensation intensity on the target braking intensity to update the target braking intensity.

Optionally, the second offset compensation intensity is subtracted on the basis of the target braking intensity, so as to compensate the target braking intensity again, and the target braking intensity after being updated again is obtained. Specifically, on the basis of the above formula (7), in combination with the above formula (13), the update target brake intensity can be expressed by the following formula (14):

（14）

Wherein, Is the target braking intensity after updating again.

It should be noted that, since the second offset compensation strength is reduced in the target brake strength, there is inevitably a case where the target brake strength after the re-update is less than 0, that isIn this case, in order to ensure that the value of the target braking intensity after the re-update is meaningful, the target braking intensity after the re-update is set to 0. That is, ifThen。

Further, in another alternative embodiment, updating of the target brake strength may be performed comprehensively based on the aforementioned first deviation compensation strength and the second deviation compensation strength in the present embodiment. Since the compensation value of the second offset compensation strength is extremely small and almost negligible, these small variations can be regarded as having no effect when considering the effect of the maximum braking strength at 100% of the travel and the small travel in the initial section of the starting position.

In summary, the following formulas may be used to comprehensively update the target brake strength based on formulas (8) - (14):

（15）

it is noted that since the second offset compensation strength is reduced in the target brake strength, there is inevitably a case where the target brake strength after the re-update is less than 0, that is In this case, in order to ensure that the value of the target braking intensity after the re-update is meaningful, the target braking intensity after the re-update is set to 0. That is, ifThen。

And S730, performing braking control on the target vehicle according to the updated target braking intensity.

According to the embodiment of the application, the second offset compensation intensity of the brake pedal is introduced according to the maximum pedal stroke, the current brake weakening degree and the minimum pedal stroke of the brake pedal, and the updated target brake intensity is compensated according to the second offset compensation intensity, so that the brake intensity of the target vehicle can be accurately simulated when the brake pedal is 0% of the stroke, and the accurate brake control of the target vehicle is further realized.

In order to enable the driver to perceive the failure of the brake system, in the embodiment of the present application, the accuracy of determining the current brake weakness is improved by simulating the braking characteristic that the secondary pressurization can improve the brake pressure. That is, it is considered that the degree of brake weakness at the time of the second depression of the brake pedal is related to the degree of brake weakness at the time of the last depression of the brake pedal. Thus, a first degree of brake weakness of the brake pedal at the current coefficient of friction may be determined first; further, the current braking weakness is determined based on braking information during a braking action preceding the current braking action.

For example, the first braking weakening degree may be determined according to the product of the current friction coefficient and the second preset coefficient, which is used as a basis for determining the current weakening degree, and then the current braking weakening degree of the brake pedal is determined in a differentiated manner according to whether the current braking behavior is the first braking behavior or not and in combination with the first braking weakening degree.

In an alternative embodiment, if the current braking behaviour is a first braking behaviour, the smaller of the first degree of braking weakness and the default momentary braking weakness is selected as the current degree of braking weakness of the brake pedal.

The instantaneous braking weakening degree is the associated braking weakening degree caused by the influence of the previous braking action, and the default instantaneous braking weakening degree is the preset instantaneous braking weakening degree. It can be understood that, since the first braking action does not have the previous braking action, a default instantaneous braking weakening degree is adopted to replace the instantaneous braking weakening degree of the previous braking action, and a smaller value is selected from the calculated first braking weakening degree and the default instantaneous braking weakening degree to be used as the current braking weakening degree of the brake pedal.

In another alternative embodiment, if the current braking action is a non-first braking action, determining the instantaneous braking weakness of the current braking action according to the instantaneous braking weakness corresponding to the previous braking action of the current braking action, the historical pedal travel of the previous braking action, and the braking interval between the current braking action and the previous braking action, and selecting the smaller value of the instantaneous braking weakness of the current braking action and the first braking weakness as the current braking weakness of the brake pedal. The instantaneous braking weakening degree corresponding to the previous braking action of the current braking action is the braking weakening degree of the previous braking action; the historical pedal travel of the previous braking action is the pedal travel of the previous braking action.

Specifically, in the case where the current behavior is a non-first braking behavior, the instantaneous braking weakness of the current braking behavior may be determined according to the influence of the instantaneous braking weakness of the previous braking behavior, the historical pedal travel, and the braking interval on the braking weakness of the current braking behavior. Further, a smaller value is selected from the first brake fade degree and the instantaneous brake fade degree of the current brake action as the current brake fade degree of the brake pedal.

Optionally, in order to ensure the accuracy of the determined instantaneous braking weakness of the current braking behaviour, the application also provides an alternative embodiment in which the step of determining the instantaneous braking weakness of the current braking behaviour is refined, the step comprising:

s810, determining the instantaneous braking weakening amplitude according to the product of the historical pedal stroke of the previous braking action and the preset stepping amplitude.

The instantaneous braking weakening amplitude is the associated braking weakening amplitude caused by the influence of the previous braking action; the preset stepping amplitude is the attenuation amplitude of the instantaneous braking attenuation degree under the condition of stepping on the full stroke of the brake pedal.

Alternatively, the braking strength may be plotted against the braking travel at different braking weakness levels as shown in fig. 4. Wherein, the horizontal axis x is a braking stroke, and the braking stroke is 0 representing a minimum value (corresponding to 0%) of the braking stroke, and the braking stroke is 10 representing a maximum value (corresponding to 100%) of the braking stroke; the vertical axis y is the braking strength; the black dotted line is a linear variation curve of the braking intensity with the braking stroke in the conventional method, that is, the reference braking intensity in the above embodiment (refer to the above formula (2)); the different solid lines correspond to different degrees of brake weakness (i.e., u in fig. 4), respectively, and the specific brake weakness values are indicated by the labels in fig. 4. As can be seen from fig. 4, as the degree of brake weakness increases gradually, the resulting curve deviates from the curve corresponding to the reference brake strength more.

Furthermore, as can be seen from fig. 4, the curve does not change much after a braking weakening of more than 13. Based on this, the preset tread amplitude may be set to 6. Specifically, the process of determining the instantaneous braking weakening amplitude according to the product of the historical pedal stroke of the previous braking action and the preset stepping amplitude can be represented by the following formula (16):

（16）

Wherein, Is the instantaneous braking weakening amplitude; the historical pedal travel, which is the previous braking action, may be expressed in percent.

Of course, the preset stepping amplitude can be set to other values, which are not limited in any way by the present application.

S820, determining the instantaneous braking compensation amplitude according to the product of the braking interval and the preset compensation amplitude.

The instantaneous braking compensation amplitude is the braking compensation amplitude caused by the influence of the previous braking action. The braking interval is the time length between the current braking action and the previous braking action; the preset compensation amplitude is the preset amplitude required to be compensated for the unit time length, and can be set by the skilled person according to the needs or experience, or can be determined through a plurality of experiments, and the application is not limited in any way. In one specific implementation, the preset compensation amplitude may be set to 1.

Alternatively, the braking weakening level is gradually restored with increasing time interval between the previous braking action and the current braking action, i.e. every 1 second increase in braking interval, the braking weakening level correspondingly declines by 1 unit. Specifically, the process of determining the instantaneous brake compensation amplitude according to the product of the brake interval and the preset compensation amplitude can be expressed by the following formula (17):

（17）

Wherein, Compensating the amplitude for instantaneous braking; Is a braking interval; The compensation amplitude may be 1, for example, for the preset compensation amplitude.

S830, determining the instantaneous braking weakening degree of the current braking action according to the instantaneous braking weakening degree, the instantaneous braking weakening degree and the instantaneous braking compensation degree corresponding to the previous braking action.

The instantaneous braking weakening degree is a quantitative degree value which is influenced by the previous braking action and used for weakening the reference braking intensity.

Alternatively, the instantaneous brake weakness of the current braking action may be calculated according to a functional relation between the instantaneous brake weakness, the instantaneous brake weakness and the instantaneous brake compensation amplitude corresponding to the previous braking action and the instantaneous brake weakness of the current braking action.

In order to ensure the accuracy of the determined instantaneous brake fade, a greater value of the target difference and the default brake fade may be selected as the second brake fade; and taking the sum value between the second braking weakening degree and the instantaneous braking compensation amplitude as the instantaneous braking weakening degree of the current braking action. The target difference value is the difference value between the instantaneous braking weakening degree corresponding to the previous braking action and the instantaneous braking weakening amplitude; the default brake fade is a preset brake fade, and in the embodiment of the present application, the default brake fade is 0.

Specifically, in combination with the above formula (16), the target difference value can be expressed by the following formula (18):

（18）

Wherein, Is the target difference; the instantaneous brake weakening degree corresponding to the previous brake action.

Further, the process of selecting the larger of the target difference value and the default brake fade degree as the second brake fade degree may be expressed according to the following formula (19):

（19）

Wherein, Indicating a second degree of brake weakness; 0 indicates a default brake fade.

Further, in combination of the above-described formula (19) and formula (17), the instantaneous brake fade of the current braking action can be expressed by the following formula (20):

（20）

Wherein, Indicating the instantaneous brake fade of the front brake behaviour. In addition, if the above formula (4) is combinedOrder in principle。

Alternatively, in combination with the above formula (8), according toFor the formula (8)Updating to obtain updated target braking strength, which can be specifically represented by the following formula (21):

（21）

Or alternatively, in combination with the above formula (14), according to For the formula (14)Updating is carried out to obtain the target braking strength after updating again, and the target braking strength can be specifically represented by the following formula (22):

（22）

it should be noted that, with respect to the above formula (22), when In the time-course of which the first and second contact surfaces,。

Or alternatively, in combination with the above formula (15), according toFor in formula (15)Updating is carried out to obtain the target braking strength after updating again, and the target braking strength can be concretely represented by the following formula (23):

（23）

it should be noted that, with respect to the above formula (23), when In the time-course of which the first and second contact surfaces,。

According to the embodiment of the application, the instantaneous braking weakening amplitude is introduced according to the product of the historical pedal stroke of the previous braking action and the preset stepping amplitude, and the instantaneous braking compensation amplitude is introduced according to the product of the braking interval and the preset compensation amplitude; further, according to the instantaneous braking weakening degree, the instantaneous braking weakening degree and the instantaneous braking compensation degree corresponding to the previous braking action, the instantaneous braking weakening degree of the current braking action is determined, the influence of the previous braking action on the current braking action is fully considered, the braking weakening degree is compensated, and the accuracy of the determined instantaneous braking weakening degree of the current braking action is ensured.

It should be noted that, as can be seen from fig. 4 in the above embodiment, when the braking strength exceeds 20%, the slope of the curve of the braking strength varying with the braking stroke varies significantly, and this variation may cause the driver to misjudge the braking performance. Therefore, in order to avoid the accident of the driver caused by misjudgment, once the braking intensity is detected to exceed 20%, the braking system in the target vehicle starts an audible and visual alarm mechanism to warn the driver that the target vehicle is in an abnormal state that the braking system is connected with additional braking force, so as to guide the driver to take necessary intervention measures in time, such as reducing the vehicle speed in time or reducing the frequency of stepping on a brake pedal, etc.

Further, the curve of the braking strength versus pedal travel of the present application shown in fig. 5 is compared with the curve of the braking strength versus pedal travel of the prior art. Wherein the horizontal axis x represents pedal travel (range 0-10) and the vertical axis y represents brake strength (range 0-10, corresponding to 0% -100% of maximum brake strength); the black solid line (i.e., curve 1) is a variation curve of the braking strength and the pedal stroke without considering the braking force decline condition in the prior art; the black dotted line (i.e., curve 2) is a variation curve of the braking strength and the pedal travel of the vehicle control method provided by the embodiment of the application; the grey dashed line (i.e. curve 3) is the weakening corrected deviation value. As can be seen from fig. 5, the control response of the front section of the curve 2 to the pedal stroke is moderately slowed down, and the expected braking force performance is gradually recovered in the subsequent stage, that is, compared with the prior art, the vehicle control method provided by the embodiment of the application can more accurately simulate the braking force attenuation state of the target vehicle, and improve the braking force attenuation perception of the driver.

On the basis of the technical solutions of the above embodiments, the present application also provides an alternative embodiment, in which the vehicle control process is described in detail.

Referring to fig. 6, the vehicle control method includes:

S901, a current wheel speed of a wheel in a target vehicle, a current piston pressure of a brake piston, and a current pedal stroke of a brake pedal under a current braking action are acquired.

S902, determining the current friction coefficient of the friction braking element in the target vehicle according to the current wheel speed and the current piston pressure.

S903, determining the reference braking strength of the brake pedal according to the product of the current pedal stroke and the first preset coefficient.

S904, determining the current braking weakening degree of the brake pedal according to the product of the current friction coefficient and the second preset coefficient.

S905, based on a preset exponential function, according to a first preset smoothing coefficient, carrying out exponential decay on the difference between the current pedal stroke and the current braking weakening degree, and determining a current decay compensation coefficient.

S906, determining the target braking intensity of the brake pedal according to the product of the current fading compensation coefficient and the reference braking intensity.

S907, based on a preset exponential function, according to a first preset smoothing coefficient, carrying out exponential decay on the difference between the maximum pedal stroke and the current braking weakening degree to obtain an offset compensation coefficient.

And S908, carrying out exponential decay on the difference value between the current pedal stroke and the maximum pedal stroke according to a second preset smoothing coefficient based on a preset exponential function, and determining the first basic compensation intensity.

Wherein the second preset smoothing coefficient is 1.

S909, determining the first offset compensation intensity of the brake pedal according to the product of the offset compensation coefficient and the first basic compensation intensity.

S910, accumulating the first offset compensation intensity on the target braking intensity to update the target braking intensity.

S911, determining a second offset compensation strength of the brake pedal according to the maximum pedal stroke, the current brake fade degree, and the minimum pedal stroke of the brake pedal.

Optionally, based on a preset exponential function, exponentially attenuating a difference between the minimum pedal stroke and the current pedal stroke according to a second preset smoothing coefficient, to determine a second base compensation intensity; a second offset compensation intensity of the brake pedal is determined based on a product of the offset compensation coefficient and the second base compensation intensity.

S912, decreasing the second offset compensation intensity on the updated target brake intensity to update the target brake intensity again.

And S913, performing braking control on the target vehicle according to the updated target braking intensity.

The specific process of the above S901-S913 may refer to the description of the above method embodiment, and its implementation principle and technical effects are similar, and are not repeated herein.

It should be understood that, although the steps in the flowcharts related to the embodiments described above are sequentially shown as indicated by arrows, these steps are not necessarily sequentially performed in the order indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least some of the steps in the flowcharts described in the above embodiments may include a plurality of steps or a plurality of stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of the steps or stages is not necessarily performed sequentially, but may be performed alternately or alternately with at least some of the other steps or stages.

Based on the same inventive concept, the embodiment of the application also provides a vehicle control device for realizing the vehicle control method. The implementation of the solution provided by the device is similar to the implementation described in the above method, so the specific limitation in one or more embodiments of the vehicle control device provided below may refer to the limitation of the vehicle control method hereinabove, and will not be repeated herein.

In one exemplary embodiment, as shown in fig. 7, there is provided a vehicle control apparatus including: an information acquisition module 1010, a coefficient determination module 1020, an intensity determination module 1030, and a brake control module 1040, wherein:

The information acquisition module 1010 is configured to acquire a current wheel speed of a wheel in the target vehicle, a current piston pressure of a brake piston, and a current pedal row of a brake pedal in a current braking action.

The coefficient determination module 1020 is configured to determine a current coefficient of friction of a friction brake in the target vehicle based on the current wheel speed and the current piston pressure.

The intensity determination module 1030 is configured to determine a target braking intensity of a brake pedal in the target vehicle according to the current friction coefficient and the current pedal stroke, in a case where the current friction coefficient satisfies a braking force attenuation condition.

The brake control module 1040 is configured to perform brake control on the target vehicle according to the target brake strength.

In one embodiment, the intensity determination module 1030 includes: a first determination unit for determining a reference brake strength of the brake pedal at a current pedal stroke. And the coefficient determining unit is used for determining the current decline compensation coefficient of the brake pedal according to the current friction coefficient and the current pedal stroke. And the second determining unit is used for determining the target braking intensity of the brake pedal according to the product of the current fading compensation coefficient and the reference braking intensity.

In one embodiment, the coefficient determination unit includes: a degree determination slave unit for determining a current degree of braking weakness of the brake pedal at a current friction coefficient. The coefficient determination slave unit is used for exponentially attenuating the difference between the current pedal stroke and the current braking weakening degree according to a first preset smooth coefficient based on a preset exponential function and determining a current fading compensation coefficient.

In one embodiment, the brake control module 1040 includes: and a first compensation determining unit for determining a first offset compensation strength of the brake pedal according to the current brake weakening degree, the current pedal stroke and the maximum pedal stroke of the brake pedal. And the first intensity updating unit is used for accumulating the first offset compensation intensity on the target braking intensity so as to update the target braking intensity. And the first brake control unit is used for performing brake control on the target vehicle according to the updated target brake intensity.

In an embodiment, the compensation determining unit is specifically configured to: based on a preset exponential function, according to a second preset smoothing coefficient, carrying out exponential decay on the difference between the current pedal stroke and the maximum pedal stroke, and determining a first basic compensation intensity; wherein the second preset smoothing coefficient is 1; based on a preset exponential function, carrying out exponential decay on the difference between the maximum pedal travel and the current braking weakening degree according to a first preset smoothing parameter to obtain an offset compensation coefficient; a first offset compensation intensity of the brake pedal is determined based on a product of the offset compensation coefficient and the first base compensation intensity.

In one embodiment, the intensity determination module 1030 includes: and a second compensation intensity determining unit for determining a second offset compensation intensity of the brake pedal according to the maximum pedal stroke, the current brake weakness degree and the minimum pedal stroke of the brake pedal. And a second intensity updating unit for reducing the second offset compensation intensity on the target braking intensity to update the target braking intensity. And the second brake control unit is used for performing brake control on the target vehicle according to the updated target brake intensity.

In one embodiment, the second compensation intensity determining unit is specifically configured to: based on a preset exponential function, according to a second preset smoothing coefficient, carrying out exponential decay on the difference between the minimum pedal stroke and the current pedal stroke, and determining a second basic compensation intensity; based on a preset exponential function, carrying out exponential decay on the difference between the maximum pedal stroke and the current braking weakening degree according to a first preset smoothing coefficient to obtain an offset compensation coefficient; a second offset compensation intensity of the brake pedal is determined based on a product of the offset compensation coefficient and the second base compensation intensity.

In one embodiment, the degree determining slave unit comprises: a determination subunit for determining a first brake fade degree of the brake pedal at the current friction coefficient. And the first selecting subunit is used for selecting the smaller value of the first braking weakening degree and the default instantaneous braking weakening degree as the current braking weakening degree of the brake pedal if the current braking behavior is the first braking behavior. And the second selecting subunit is configured to determine, if the current braking behavior is not the first braking behavior, an instantaneous braking weakness degree of the current braking behavior according to an instantaneous braking weakness degree corresponding to a previous braking behavior of the current braking behavior, a historical pedal stroke of the previous braking behavior, and a braking interval between the current braking behavior and the previous braking behavior, and select, as the current braking weakness degree of the brake pedal, a smaller value of the first braking weakness degree and the instantaneous braking weakness degree of the current braking behavior.

In one embodiment, the second selecting subunit is specifically configured to: determining instantaneous braking weakening amplitude according to the product of the historical pedal stroke of the previous braking action and the preset stepping amplitude; determining an instantaneous braking compensation amplitude according to the product of the braking interval and a preset compensation amplitude; and determining the instantaneous braking weakening degree of the current braking action according to the instantaneous braking weakening degree, the instantaneous braking weakening degree and the instantaneous braking compensation degree corresponding to the previous braking action.

In one embodiment, the second pick subunit is further configured to: selecting a larger value of the target difference value and the default brake weakening degree as a second brake weakening degree; the target difference value is the difference value between the instantaneous braking weakening degree and the instantaneous braking weakening amplitude corresponding to the previous braking action; and taking the sum value between the second braking weakening degree and the instantaneous braking compensation amplitude as the instantaneous braking weakening degree of the current braking action.

Each of the modules in the vehicle control apparatus described above may be implemented in whole or in part by software, hardware, and a combination thereof. The above modules may be embedded in hardware or may be independent of a processor in the computer device, or may be stored in software in a memory in the computer device, so that the processor may call and execute operations corresponding to the above modules.

In one exemplary embodiment, a computer device is provided, which may be a server, and the internal structure thereof may be as shown in fig. 8. The computer device includes a processor, a memory, an Input/Output interface (I/O) and a communication interface. The processor, the memory and the input/output interface are connected through a system bus, and the communication interface is connected to the system bus through the input/output interface. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input/output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a vehicle control method.

It will be appreciated by those skilled in the art that the structure shown in FIG. 8 is merely a block diagram of some of the structures associated with the present inventive arrangements and is not limiting of the computer device to which the present inventive arrangements may be applied, and that a particular computer device may include more or fewer components than shown, or may combine some of the components, or have a different arrangement of components.

In one embodiment, a computer device is provided that includes a memory having a computer program stored therein and a processor that when executing the computer program performs the steps of the vehicle control method described above.

In an alternative embodiment, the application also provides a vehicle in which the computer device shown in fig. 8 is provided.

In one embodiment, a computer readable storage medium is provided having a computer program stored thereon, which when executed by a processor, implements the steps of the vehicle control method described above.

In one embodiment, a computer program product is provided comprising a computer program which, when executed by a processor, implements the steps of the vehicle control method described above.

It should be noted that, the data (including, but not limited to, data for analysis, data stored, data displayed, etc.) related to the present application are information and data fully authorized by each party, and the collection, use and processing of the related data are required to meet the related regulations.

Those skilled in the art will appreciate that implementing all or part of the above described methods may be accomplished by way of a computer program stored on a non-transitory computer readable storage medium, which when executed, may comprise the steps of the embodiments of the methods described above. Any reference to memory, database, or other medium used in embodiments provided herein may include at least one of non-volatile memory and volatile memory. The nonvolatile Memory may include Read-Only Memory (ROM), magnetic tape, floppy disk, flash Memory, optical Memory, high density embedded nonvolatile Memory, resistive random access Memory (RESISTIVE RANDOM ACCESS MEMORY, reRAM), magneto-resistive Memory (Magnetoresistive Random Access Memory, MRAM), ferroelectric Memory (Ferroelectric Random Access Memory, FRAM), phase change Memory (PHASE CHANGE Memory, PCM), graphene Memory, and the like. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory, and the like. By way of illustration, and not limitation, RAM can be in various forms such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), etc. The databases referred to in the embodiments provided herein may include at least one of a relational database and a non-relational database. The non-relational database may include, but is not limited to, a blockchain-based distributed database, and the like. The processor referred to in the embodiments provided in the present application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic unit, a data processing logic unit based on quantum computation, an artificial intelligence (ARTIFICIAL INTELLIGENCE, AI) processor, or the like, but is not limited thereto.

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the present application.

The foregoing examples illustrate only a few embodiments of the application and are described in detail herein without thereby limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of the application should be assessed as that of the appended claims.

Claims

1. A vehicle control method, characterized in that the method comprises:

2. The method of claim 1, wherein said determining a target brake strength of a brake pedal in the target vehicle based on the current coefficient of friction and the current pedal travel comprises:

Determining a reference brake strength of the brake pedal under a current pedal stroke;

determining a current fade compensation coefficient of the brake pedal according to the current friction coefficient and the current pedal travel;

And determining the target braking intensity of the brake pedal according to the product of the current fading compensation coefficient and the reference braking intensity.

3. The method of claim 2, wherein said determining a current fade compensation coefficient for said brake pedal based on said current coefficient of friction and said current pedal travel comprises:

determining a current brake weakness of the brake pedal at a current coefficient of friction;

And based on a preset exponential function, according to a first preset smoothing coefficient, carrying out exponential decay on the difference between the current pedal stroke and the current braking weakening degree, and determining a current decay compensation coefficient.

4. A method according to claim 3, wherein said brake control of said target vehicle in accordance with said target brake strength comprises:

Determining a first offset compensation strength of the brake pedal according to the current brake weakness, the current pedal stroke and a maximum pedal stroke of the brake pedal;

accumulating the first offset compensation intensity over the target brake intensity to update the target brake intensity;

and according to the updated target braking intensity, performing braking control on the target vehicle.

5. The method of claim 4, wherein said determining a first offset compensation strength of said brake pedal based on said current brake fade, said current pedal travel, and a maximum pedal travel of said brake pedal comprises:

Based on the preset exponential function, carrying out exponential decay on the difference value between the current pedal stroke and the maximum pedal stroke according to a second preset smoothing coefficient, and determining a first basic compensation intensity; wherein the second preset smoothing coefficient is 1;

based on the preset exponential function, according to the first preset smoothing coefficient, carrying out exponential decay on the difference between the maximum pedal stroke and the current braking weakening degree to obtain an offset compensation coefficient;

a first offset compensation intensity of the brake pedal is determined based on a product of the offset compensation coefficient and the first base compensation intensity.

6. The method according to any one of claims 3 to 5, wherein the brake control of the target vehicle according to the target brake intensity includes:

Determining a second offset compensation strength of the brake pedal based on the maximum pedal travel, the current brake weakness, and a minimum pedal travel of the brake pedal;

Reducing the second offset compensation intensity on the target brake intensity to update the target brake intensity;

7. The method of claim 6, wherein said determining a second offset compensation strength of said brake pedal based on said maximum pedal travel, said current brake fade, and a minimum pedal travel of said brake pedal comprises:

based on the preset exponential function, according to the second preset smoothing coefficient, carrying out exponential decay on the difference value between the minimum pedal stroke and the maximum pedal stroke, and determining a second basic compensation intensity;

And determining a second offset compensation intensity of the brake pedal according to the product of the offset compensation coefficient and the second basic compensation intensity.

8. The method of any one of claims 3-5, wherein said determining a current brake weakness of the brake pedal at a current coefficient of friction comprises:

determining a first brake weakness of the brake pedal at the current coefficient of friction;

If the current braking behavior is a first braking behavior, selecting the smaller value of the first braking weakening degree and a default instantaneous braking weakening degree as the current braking weakening degree of the brake pedal;

If the current braking behavior is a non-first braking behavior, determining the instantaneous braking weakening degree of the current braking behavior according to the instantaneous braking weakening degree corresponding to the previous braking behavior of the current braking behavior, the historical pedal travel of the previous braking behavior and the braking interval between the current braking behavior and the previous braking behavior, and selecting the smaller value of the instantaneous braking weakening degree of the current braking behavior and the first braking weakening degree as the current braking weakening degree of the brake pedal.

9. The method of claim 8, wherein the determining the instantaneous brake weakness of the current braking action based on the corresponding instantaneous brake weakness of the previous braking action of the current braking action, the historical pedal travel of the previous braking action, and the braking interval between the current braking action and the previous braking action comprises:

Determining an instantaneous braking weakening amplitude according to the product of the historical pedal travel of the previous braking action and a preset stepping amplitude; and

Determining an instantaneous braking compensation amplitude according to the product of the braking interval and a preset compensation amplitude;

And determining the instantaneous braking weakening degree of the current braking action according to the instantaneous braking weakening degree, the instantaneous braking weakening degree and the instantaneous braking compensation degree corresponding to the previous braking action.

10. The method of claim 9, wherein said determining the instantaneous brake weakness of the current braking action based on the corresponding instantaneous brake weakness of the previous braking action, the instantaneous brake weakness and the instantaneous brake compensation amplitude comprises:

selecting a larger value of the target difference value and the default brake weakening degree as a second brake weakening degree; the target difference value is the difference value between the instantaneous braking weakening degree corresponding to the previous braking action and the instantaneous braking weakening amplitude;

And taking the sum value between the second braking weakening degree and the instantaneous braking compensation amplitude as the instantaneous braking weakening degree of the current braking action.

11. A vehicle control apparatus, characterized in that the apparatus comprises:

12. A vehicle, characterized in that it is provided with a device for implementing the method according to any one of claims 1-10.