CN115402111A

CN115402111A - Brake control method and device and vehicle body controller

Info

Publication number: CN115402111A
Application number: CN202111153056.7A
Authority: CN
Inventors: 贾彩娜
Original assignee: Beijing Co Wheels Technology Co Ltd
Current assignee: Beijing Co Wheels Technology Co Ltd
Priority date: 2021-09-29
Filing date: 2021-09-29
Publication date: 2022-11-29

Abstract

The embodiment of the application provides a brake control method and device and a vehicle body controller. Determining at least one functional safety representation signal of the vehicle and a first brake torque limit value, wherein the first brake torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety grade; judging whether the first braking torque limit value is correct or not according to the at least one functional safety representation signal; if so, determining that the first braking torque limit value is the braking torque limit value of the vehicle; if not, calculating a second braking torque limit value according to the at least one function safety representation signal, and determining the second braking torque limit value as the braking torque limit value of the vehicle. The technical scheme provided by the embodiment of the application improves the driving safety.

Description

Brake control method and device and vehicle body controller

Technical Field

The embodiment of the application relates to the technical field of new energy automobiles, in particular to a brake control method and device and an automobile body controller.

Background

Due to the characteristics of energy conservation, small pollution and the like, the new energy automobile is rapidly developed. Unlike a conventional fuel automobile, the new energy automobile has a driving motor, which drives the vehicle to move by converting electric energy into mechanical energy, and coordinates a regenerative Braking System (CRBS) function, which stops the vehicle from moving by generating a Braking torque. In vehicle safety control, the braking torque is usually limited within a certain range. In a conventional scheme, a braking torque limit value is calculated, and the braking torque is monitored by using the braking torque limit value, so that when the braking torque exceeds the limit value, a vehicle is controlled in a safe state.

Therefore, ensuring the accuracy of the setting of the braking torque limit value plays an important role in controlling the safety of the whole vehicle.

Disclosure of Invention

The embodiment of the application provides a brake control method, a brake control device and a vehicle body controller, which are used for improving driving safety.

In a first aspect, an embodiment of the present application provides a brake control method, including:

determining at least one functional safety characteristic signal of the vehicle and a first brake torque limit value, wherein the first brake torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety level;

judging whether the first braking torque limit value is correct or not according to the at least one functional safety representation signal;

if so, determining that the first braking torque limit value is the braking torque limit value of the vehicle;

if not, calculating a second braking torque limit value according to the at least one functional safety representation signal, and determining the second braking torque limit value as the braking torque limit value of the vehicle.

In a second aspect, an embodiment of the present application provides a brake control apparatus, including:

the first determining module is used for determining at least one functional safety representation signal of the vehicle and a first brake torque limit value, and the first brake torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety grade;

the judging module is used for judging whether the first braking torque limit value is correct or not according to the at least one functional safety representation signal;

the second determining module is used for determining that the first braking torque limit value is the braking torque limit value of the vehicle if the judging module has a positive result;

and the third determining module is used for calculating a second braking torque limit value according to the at least one functional safety representation signal and determining the second braking torque limit value as the braking torque limit value of the vehicle if the judging module has no result.

In a third aspect, an embodiment of the present application provides a vehicle body controller, including a storage component and a processing component;

the storage component stores one or more computer instructions for the processing component to invoke for execution;

and when the processing component calls the computer instruction, the brake control method of the first aspect is executed.

In the embodiment of the application, the first braking torque limit value is judged by using at least one functional safety representation signal, so that monitoring of the first braking torque limit value is realized, the functional safety representation signal can represent the functional safety of the whole vehicle, if the first braking torque limit value is judged to be correctly calculated according to the functional safety representation signal, the first braking torque limit value can be determined to be reasonably set, the first braking torque limit value can be used for limiting the braking torque, and the driving safety is ensured; if the first braking torque limit value is judged to be calculated incorrectly according to the functional safety representation signal, the first braking torque limit value can be determined to be unreasonably set, and the driving safety can be damaged. By monitoring the braking torque limit value, the braking torque is limited by using a reasonable braking torque limit value, the conditions of unexpected deceleration of the whole vehicle or unexpected reverse movement of the whole vehicle and the like are avoided, and the driving safety is ensured.

These and other aspects of the present application will be more readily apparent from the following description of the embodiments.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following descriptions are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a flow chart illustrating one embodiment of a brake control method provided herein;

FIG. 2 is a flow chart illustrating another embodiment of a brake control method provided herein;

FIG. 3 is a schematic block diagram illustrating one embodiment of a brake control system architecture provided herein;

FIG. 4 is a schematic block diagram illustrating one embodiment of a brake control apparatus provided herein;

fig. 5 shows a schematic structural diagram of an embodiment of a vehicle body controller provided by the present application.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

In some of the flows described in the specification and claims of this application and in the above-described figures, a number of operations are included that occur in a particular order, but it should be clearly understood that these operations may be performed out of order or in parallel as they occur herein, the number of operations, e.g., 101, 102, etc., merely being used to distinguish between various operations, and the number itself does not represent any order of performance. Additionally, the flows may include more or fewer operations, and the operations may be performed sequentially or in parallel. It should be noted that, the descriptions of "first", "second", etc. in this document are used for distinguishing different messages, devices, modules, etc., and do not represent a sequential order, nor limit the types of "first" and "second" to be different.

The technical scheme that this application provided is applicable to among the car function safety scene, especially is applicable to new energy automobile function safety scene. The new energy automobile is an automobile which adopts unconventional automobile fuel as a power source (or adopts conventional automobile fuel and a novel vehicle-mounted power device), integrates advanced technologies in the aspects of power control and driving of the automobile, and is advanced in technical principle, novel in technology and novel in structure. The new energy automobile can comprise four types of Hybrid Electric Vehicles (HEV), pure electric vehicles (BEV including solar vehicles), fuel Cell Electric Vehicles (FCEV), other new energy (high efficiency energy storage such as super capacitors, flywheels, and the like) automobiles and the like. Unlike a conventional fuel automobile, the new energy automobile has a driving motor, which drives the vehicle to move by converting electric energy into mechanical energy, and coordinates a regenerative Braking System (CRBS) function, which stops the vehicle from moving by generating a Braking torque. In the safety control of the whole vehicle function, the braking torque is usually limited within a certain range. The braking torque limit may be used to monitor the braking torque, typically by calculating a braking torque limit, so that the vehicle is controlled to a safe state when the braking torque exceeds the limit.

If the braking torque limit value is not reasonably set, the whole vehicle may move abnormally, so that the driving safety is damaged. For example, if the unexpected output of the braking torque limit value is a large negative value, unexpected deceleration of the whole vehicle will occur; if the brake torque limit value is unexpectedly clamped at a large negative value, unexpected reverse motion of the whole vehicle can be caused. Therefore, the reasonable setting of the braking torque limit value is ensured, and the important function of the safety control of the whole vehicle function is played.

However, in the conventional solution, the braking torque limit value is usually obtained directly according to the function signal, and the braking torque limit value is not monitored, so that the correctness of the braking torque limit value cannot be judged. Therefore, in order to ensure that the braking torque limit value is reasonably set, the inventor provides a technical scheme of the application through a series of thinking and experiments, and provides a braking control method, which comprises the steps of determining at least one functional safety representation signal of a vehicle and a first braking torque limit value, wherein the first braking torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety grade; judging whether the first braking torque limit value is correct or not according to the at least one functional safety representation signal; if so, determining that the first braking torque limit value is the braking torque limit value of the vehicle; if not, calculating a second braking torque limit value according to the at least one functional safety representation signal, and determining the second braking torque limit value as the braking torque limit value of the vehicle.

According to the method, the first brake torque limit value is judged by using at least one functional safety representation signal, so that the first brake torque limit value is monitored, the functional safety representation signal can represent the whole vehicle functional safety, if the first brake torque limit value is judged to be correctly calculated according to the functional safety representation signal, the first brake torque limit value can be determined to be reasonably set, the first brake torque limit value can be used for limiting the brake torque, and the driving safety is ensured; if the first braking torque limit value is judged to be calculated incorrectly according to the functional safety representation signal, the fact that the first braking torque limit value is set unreasonably can be determined, driving safety can be endangered, at the moment, the second braking torque limit value is recalculated according to the at least one functional safety representation signal, and the braking torque is limited by the second braking torque limit value. By monitoring the braking torque limit value, the braking torque is limited by using a reasonable braking torque limit value, the conditions of unexpected deceleration of the whole vehicle or unexpected reverse movement of the whole vehicle and the like are avoided, and the driving safety is ensured.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

As shown in fig. 1, a flowchart of an embodiment of a brake control method provided herein may include the following steps:

101: at least one functional safety characterizing signal and a first brake torque limit value are determined.

Wherein the first brake torque limit is calculated based on at least one function signal.

In this embodiment, the function signal may refer to all function signals related to vehicle braking, and may include a motor rotation speed, a motor system efficiency, a vehicle speed, a braking state, and the like. Based on the at least one function signal, a brake torque limit value can be calculated for limiting the brake torque generated when the vehicle is braked. Where the braking torque is negative, the braking torque limit is also implemented as a negative value, for example, the braking torque limit may be-10N · m (newton · m), -20N · m, etc.

The functional Safety characterization signal may refer to a functional signal related to vehicle braking and having a functional Safety Level (ASIL), where the ASIL may include four levels, i.e., a, B, C, and D. Where A is the lowest rank and D is the highest rank. For example, the functional safety characterizing signal may include vehicle speed, brake status, and the like. The ASIL level of the entire vehicle speed is C, and the ASIL level of the braking state is C.

Specifically, the implementation manner of calculating the braking torque limit value according to the at least one function signal may refer to an implementation manner in a conventional scheme, and the at least one function safety characterization signal may be determined according to an actual application scenario, which is not limited in the embodiment of the present application.

102: and judging whether the first braking torque limit value is correct or not according to the at least one functional safety representation signal. If yes, execute the method of step 103; if the determination result is negative, the method of step 104 is executed.

The braking torque limit value is obtained by calculation according to at least one function signal, and the function signal comprises signals without function safety level, such as motor rotating speed, and the braking torque limit value obtained by calculation is not necessarily a reasonable limit value for ensuring driving safety. Therefore, it is necessary to determine the correctness of the brake torque limit value.

Considering that the functional safety representation signal has a functional safety level, the correctness of the braking torque limit value can be judged according to at least one functional safety representation signal, so that whether the limitation of the braking torque by using the braking torque limit value is reasonable or not is determined. In an alternative embodiment, the at least one function signal includes a motor speed, the braking torque limit calculated according to the motor speed is a negative value, such as-10N · m, and the at least one function safety characterizing signal includes a braking state, if the entire vehicle is in the braking state, indicating that a user has a braking demand, the braking torque can be generated to stop the vehicle, and since the braking torque is a negative value, when the braking torque is limited by the braking torque limit, the vehicle can generate a reasonable braking torque, such as-5N · m, so that the limit is correct. If the whole vehicle is not in a braking state, the braking torque needs to be prohibited to stop the vehicle from moving, and when the braking torque is limited by the limiting value of the braking torque, the vehicle can still stop moving due to the braking torque generated by the vehicle, so that the driving safety cannot be ensured, and therefore the limiting value is incorrect.

Specifically, there may be multiple implementation manners for determining whether the braking torque limit value is correct according to at least one functional safety representation signal, which will be described in the following embodiments, and details are not described here.

103: the first brake torque limit is determined as a brake torque limit for the vehicle.

If the braking torque limit value is determined to be correct, the braking torque can be limited by using the limit value. For example, if the braking torque limit is-8N m, the limiting condition for the braking torque may be that a braking torque in the range of-8N m to 0N m can stop the vehicle from moving. Therefore, when the braking torque generated by the vehicle is in the range of-8N · m to 0N · m, the vehicle can be stopped from moving based on the braking torque; when the braking torque generated by the vehicle is not within the above range, the vehicle is stopped based on the braking torque limit. Specifically, the implementation manner of limiting the braking torque by using the braking torque limit value may refer to the implementation manner in the conventional scheme, which is not limited in the embodiment of the present application.

104: a second brake torque limit is calculated based on the at least one functional safety characteristic signal and the second brake torque limit is determined as a brake torque limit for the vehicle.

If the braking torque limit value is judged to be incorrect, the braking torque cannot be limited by the limit value, and the braking torque limit value needs to be recalculated at the moment. For ease of description, the above-described braking torque limit may be referred to as a first braking torque limit, and the recalculated braking torque limit may be referred to as a second braking torque limit. Wherein the first brake torque limit is calculated based on at least one function signal and the second brake torque limit is calculated based on at least one function safety characterizing signal.

It can be understood that the at least one functional safety characterizing signal is a signal with a functional safety level, and the second braking torque limit value obtained through calculation is a reasonable limit value for ensuring driving safety, and the braking torque can be limited by using the second braking torque limit value. Alternatively, the second brake torque limit may be 0N · m. In an alternative embodiment, the first braking torque limit calculated from the at least one function signal is a negative value, such as-10N · m, and the at least one function safety characterizing signal includes a braking state, and the first braking torque limit is incorrect if the vehicle is not in the braking state as can be seen from the above analysis. Alternatively, the second braking torque limit determined according to the braking state may be 0N · m. At the moment, when the braking torque is limited by the second braking torque limit value, the negative braking torque generated by the vehicle does not meet the limiting condition, and the vehicle cannot stop moving, so that the braking torque is matched with a signal that the whole vehicle is not in a braking state, the driving safety is ensured, and the reasonable limitation on the braking torque is realized.

In the embodiment, the first braking torque limit value is judged by using at least one functional safety representation signal, so that the monitoring of the first braking torque limit value is realized, the functional safety representation signal can represent the whole vehicle functional safety, if the first braking torque limit value is judged to be correctly calculated according to the functional safety representation signal, the first braking torque limit value can be determined to be reasonably set, and the first braking torque limit value can be used for limiting the braking torque, so that the driving safety is ensured; if the first braking torque limit value is judged to be calculated incorrectly according to the functional safety representation signal, the fact that the first braking torque limit value is set unreasonably can be determined, driving safety can be endangered, at the moment, the second braking torque limit value is recalculated according to the at least one functional safety representation signal, and the braking torque is limited by the second braking torque limit value. By monitoring the braking torque limit value, the braking torque is limited by using a reasonable braking torque limit value, the conditions of unexpected deceleration of the whole vehicle or unexpected reverse movement of the whole vehicle and the like are avoided, and the driving safety is ensured.

In order to improve the accuracy of the judgment, at least one functional safety representation signal can be verified in advance, and the correctness of the first braking torque limit value can be judged by using the verification result. As shown in fig. 2, a flowchart of another embodiment of a brake control method provided herein may include the following steps:

201: at least one functional safety characterizing signal and a first brake torque limit value are determined.

Specifically, the implementation manner of step 201 may refer to the specific implementation manner of step 101 in the embodiment shown in fig. 1, and is not described herein again.

202: and acquiring a verification result of at least one functional safety characteristic signal, wherein the verification result is obtained by performing end-to-end verification on the at least one functional safety characteristic signal.

In the vehicle safety control, the generation devices of the function signals are different, and the generation devices are different from the devices for calculating the braking torque limit value. When the brake torque limit value is calculated, corresponding function signals need to be acquired from generating devices of the function signals, and in the process that the function signals are transmitted from the corresponding generating devices to the brake torque limit value calculating device through a communication protocol, the function signals received by the brake torque limit value calculating device are inconsistent with the function signals sent by the generating devices, namely, the function signals received by the brake torque limit value calculating device are wrong, and the brake torque limit value obtained by calculation based on the wrong function signals is also wrong.

Therefore, in this embodiment, at least one functional safety characterizing signal used for calculation needs to be verified, and a corresponding verification result needs to be obtained. Optionally, the verification result may be an end-to-end (E2E for short) verification result. The E2E verification can judge whether the signal received by the braking torque limit value calculation device is consistent with the transmitted signal in the transmission process of the function safety representation signal, if not, a user can know that the received signal is wrong, so that the correctness of the first braking torque limit value is judged, or the signal is obtained again, the second braking torque limit value is recalculated, and other subsequent processing is carried out, and the wrong braking torque limit value is prevented from being calculated and obtained based on the wrong received signal.

Specifically, the implementation manner of obtaining the verification result of the at least one functional safety representation signal may refer to a specific implementation manner in a conventional scheme, and the embodiment of the present application is not limited.

203: and judging whether the first braking torque limit value is correct or not according to the verification result of the at least one functional safety representation signal. If yes, execute the method of step 204; if not, the method of step 205 is executed.

After obtaining the verification result of the at least one functional safety characterizing signal, it may be determined whether the first braking torque limit value is correct based on the verification result.

Specifically, whether the check result of the at least one functional safety representation signal is wrong or not can be judged, and the first braking torque limit value is a negative value, if yes, the first braking torque limit value is determined to be incorrect, and if not, the first braking torque limit value is determined to be correct.

When the check result is wrong, it indicates that the actually received function safety representation signal is wrong, such as the speed of the whole vehicle is wrong, the braking state judgment is wrong, and the like, at this time, in order to ensure the driving safety, the generation of abnormal braking torque is required to be avoided so as to stop the whole vehicle from moving. The braking torque limit value should not be negative, otherwise the vehicle cannot be limited to generate negative braking torque for braking. Therefore, if the check result is incorrect, the first braking torque limit value is a negative value, and it can be determined that the first braking torque limit value is incorrect.

When the check result is wrong, but the first braking torque limit value is not a negative value, if the first braking torque limit value is 0N · m, the vehicle can be limited to generate negative braking torque for braking, so that the vehicle is prevented from generating abnormal braking torque to stop the whole vehicle. The first brake torque limit may be determined to be correct at this time.

When the verification result is correct, the actually received function safety representation signal is correct, and the vehicle can normally generate braking torque to stop the whole vehicle from moving. The braking torque limit value at this time may be implemented as a negative value, and therefore, it may be judged that the first braking torque limit value is correct.

204: the first brake torque limit is determined as a brake torque limit of the vehicle.

205: a second brake torque limit is calculated based on the at least one functional safety characteristic signal and the second brake torque limit is determined as a brake torque limit for the vehicle.

Specifically, the implementation manner of steps 204 to 205 may refer to the specific implementation manner of steps 103 to 104 in the embodiment shown in fig. 1, and is not described herein again.

In this embodiment, at least one functional safety representation signal is checked in advance to obtain a check result, and the correctness of the first braking torque limit value is determined by using the check result, so that the accuracy of the determination can be improved, and the accuracy of the calculation of the second braking torque limit value can be improved.

In practical applications, optionally, the at least one functional safety characterizing signal may include at least one of a braking torque, a motor failure level, a vehicle speed, an operation mode, and a braking state. The braking torque can refer to the braking torque generated by the vehicle, and the braking torque value can be used for representing functional safety. The motor fault levels may include Active Short Circuit (ASC), free running (FW), etc., the vehicle speed may refer to the vehicle speed, the operation mode may include overspeed mode, adaptive Cruise Control (ACC OVRD), etc., and the brake state may include brake pedal state, accelerator pedal state, etc.

Thus, in some embodiments, the method of determining whether the first brake torque limit is correct based on the at least one functional safety characterization signal may include:

and judging whether the first braking torque limit value is a negative value or not, and at least one functional safety representation signal of the braking torque, the motor fault grade, the vehicle speed, the running mode and the braking state meets the respective corresponding judgment condition, if so, determining that the first braking torque limit value is incorrect, otherwise, determining that the first braking torque limit value is correct.

It is understood that the different function safety characterization signals correspond to different functions, and the manner of calculating the braking torque limit value is different, so that when the first braking torque limit value is determined based on the different function safety characterization signals, the determination conditions are also corresponding to the different function safety characterization signals. And judging whether at least one functional safety representation signal in the braking torque, the motor fault grade, the vehicle speed, the running mode and the braking state meets the respective corresponding judgment condition, thereby determining whether the first braking torque limit value is correct or not and having multiple optional implementation modes.

As an optional implementation manner, when one or more of the at least one functional safety characterizing signal satisfies the respective corresponding determination condition, it is determined that the first braking torque limit value is incorrect, otherwise, it is determined that the first braking torque limit value is correct.

As another optional implementation manner, when all of the at least one functional safety characterizing signal satisfies the respective corresponding determination condition, it is determined that the first braking torque limit value is incorrect, otherwise, it is determined that the first braking torque limit value is correct.

The following will describe the determination of whether the braking torque, the motor failure level, the vehicle speed, the operation mode, and the braking state satisfy the respective determination conditions.

In an alternative embodiment, the at least one functional safety characterizing signal may comprise a braking torque. The method for determining whether the first braking torque limit value is a negative value and the braking torque meets the corresponding determination condition may include:

it is determined whether the braking torque at which the first braking torque limit is calculated does not match the braking torque requested by the vehicle and the first braking torque limit is a negative value.

Specifically, the braking torque for calculating the first braking torque limit value may refer to the braking torque received by the braking torque calculation device, the braking torque requested by the vehicle may refer to the actual braking torque sent by the braking torque generation device, when the braking torque and the actual braking torque are not matched, it is necessary to avoid that the vehicle generates an abnormal braking torque to perform braking, and the first braking torque limit value should not be implemented as a negative value. Where the first brake torque limit is negative, it may be determined that the limit is incorrect.

Alternatively, an E2E check result of the braking torque may be obtained, and when the check result is faulty, it is determined that the braking torque for calculating the first braking torque limit value does not match the braking torque requested by the vehicle.

In another optional embodiment, the at least one functional safety characterizing signal comprises a motor fault level. The method for determining whether the first braking torque limit value is a negative value and the motor fault level meets the corresponding determination condition may include:

and judging whether the motor fault level reaches a preset fault level or not, wherein the first braking torque limit value is a negative value.

In this embodiment, the preset fault level may include FW or ASC, and the preset fault level may be set according to an actual application scenario. When the motor fault level is FW or ASC, the vehicle cannot normally generate the braking torque, and the first braking torque limit value should not be realized to be a negative value at this time. Where the first brake torque limit is negative, it may be determined that the limit is incorrect.

Optionally, an E2E check result of the motor fault level may be obtained, and when the check result is faulty, the motor fault level is determined to be FW or ASC.

In yet another alternative embodiment, the at least one functional safety characterizing signal may include vehicle speed. The method for judging whether the first braking torque limit value is a negative value or not and the vehicle speed of the whole vehicle meets the corresponding judgment condition can comprise the following steps:

and judging whether the vehicle speed of the whole vehicle is less than a preset vehicle speed threshold value or not, wherein the first braking torque limit value is a negative value.

In this embodiment, the vehicle speed threshold may correspond to a vehicle speed before the vehicle stops moving or when the vehicle initially travels. It will be appreciated that the braking torque is already generated before the vehicle stops moving, and there is no need to generate the braking torque again to brake the vehicle; during initial running, no braking demand exists, and braking torque does not need to be generated for braking. Therefore, when the vehicle speed of the whole vehicle is smaller than the vehicle speed threshold of the whole vehicle, the braking torque needs to be prohibited to stop the vehicle from moving, and the first braking torque limit value should not be realized to be a negative value at the moment. When the first brake torque limit is a negative value, it may be determined that the limit is incorrect. The vehicle speed threshold of the whole vehicle can be preset, such as 15kph.

Specifically, an E2E check result of the vehicle speed of the whole vehicle may be obtained, and when the check result is faulty, it is determined that the vehicle speed of the whole vehicle is smaller than a vehicle speed threshold of the whole vehicle.

In yet another alternative embodiment, the at least one functional safety characterizing signal may comprise an operational mode. The method of determining whether the first braking torque limit is negative and the operating mode satisfies the corresponding determination condition may include:

and judging whether the running mode is a preset mode or not, wherein the first braking torque limit value is a negative value.

In this embodiment, the preset mode may refer to an ACC OVRD mode, and the preset mode may be set according to an actual application scenario. When the whole vehicle running mode is the ACC OVRD mode, a user has a requirement for accelerating the vehicle and does not need to generate braking torque to brake the vehicle, and the first braking torque limit value is not realized to be a negative value at the moment. Where the first brake torque limit is negative, it may be determined that the limit is incorrect.

Specifically, the operation mode may be determined to be the preset mode by obtaining an E2E check result of the operation mode and when the check result is faulty.

In yet another alternative embodiment, the at least one functional safety characterizing signal may comprise a braking state. The method for determining whether the first braking torque limit value is a negative value and the braking state meets the corresponding determination condition may include:

and judging whether the duration of the braking state is less than the preset braking time or not, and the first braking torque limit value is a negative value.

Specifically, when the entire vehicle is in the braking state, it may be indicated that the user has a braking demand, for example, the entire vehicle may be in the braking state by pressing down a brake pedal. In practical application, the condition that a user touches the brake pedal by mistake exists, and in order to avoid the condition that the error touch influences the judgment of the braking state of the whole vehicle, in the embodiment, whether the duration time of the braking state is shorter than the preset braking time or not can be judged. The preset braking time may be set according to an actual application scenario, for example, may be 1s. If the duration is less than the preset braking time, it can be determined that the user has no braking demand and the braking state is wrong. At this time, it is necessary to inhibit the braking torque to stop the vehicle from moving, and the first braking torque limit value should not be realized to be negative. When the first brake torque limit is a negative value, it may be determined that the limit is incorrect.

Specifically, whether the duration time of the braking state is less than the preset braking time may be determined by obtaining an E2E check result of the braking state. For example, it may be determined that the duration of the braking state is less than the preset braking time according to the verification result when the accelerator pedal is depressed within the time that the brake pedal is depressed is less than the preset time.

In order to improve the accuracy of monitoring the first braking torque limit value, when the verification result of the at least one functional safety representation signal is correct and the first braking torque limit value is a negative value, the value of the first braking torque limit value can be judged. Optionally, a second brake torque limit may be calculated from the at least one functional safety characterizing signal;

and judging whether the difference value between the second braking torque limit value and the first braking torque limit value is smaller than a preset difference value threshold value, if so, determining that the first braking torque limit value is correct, and otherwise, determining that the first braking torque limit value is incorrect.

In practical application, the braking torque limit value calculated according to the at least one functional safety representation signal is a braking torque limit value capable of ensuring driving safety, the value of the first braking torque limit value can be judged by using the braking torque limit value, and if the difference value between the first braking torque limit value and the first braking torque limit value is smaller than a preset difference threshold value, the first braking torque limit value can be judged and driving safety can also be ensured. The preset difference threshold may be set according to an actual application scenario, for example, may be 10N · m,20N · m, and the like, and is not limited herein.

In practical application, the correctness of the first braking torque limit value can be judged by utilizing at least one functional safety representation signal by utilizing an electronic throttle valve (EGAS) system architecture. Fig. 3 is a schematic structural diagram illustrating an embodiment of an EGAS system architecture provided in the present application. The EGAS system architecture is a three-layer software architecture, the first layer can carry out normal function calculation, and the second layer can monitor the calculation result of the first layer and judge whether the calculation result of the first layer is correct or not. In this embodiment, the first braking torque limit value may be calculated and obtained according to the at least one function signal at a first layer of the EGAS system architecture, and the correctness of the first braking torque limit value may be determined at a second layer. As shown in the figure, level1 represents a first layer, level1 outputs a first braking torque limit value to level2, at least one functional safety representation signal can also be input to level2, and the correctness of the first braking torque limit value is judged at level 2.

Alternatively, level2 may output a second brake torque limit.

For convenience, when level2 outputs a judgment result, a flag bit may be set, for example, when the flag bit is at position 1, it indicates that the first braking torque limit value is correct, and the first braking torque limit value may be output; when position 0 is flagged, indicating that the first brake torque limit is incorrect, a second brake torque limit is output.

Through the EGAS system architecture, the correctness of the first braking torque limit value can be judged by utilizing at least one functional safety representation signal, and the judgment feasibility is improved.

As shown in fig. 4, a schematic structural diagram of an embodiment of a brake control apparatus provided in the present application may include the following modules:

a first determining module 401, configured to determine at least one functional safety representation signal of a vehicle and a first braking torque limit value, where the first braking torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety level;

a determining module 402, configured to determine whether the first braking torque limit value is correct according to at least one functional safety characterization signal;

a second determining module 403, configured to determine that the first braking torque limit is a braking torque limit of the vehicle if the result of the determining module 402 is yes;

and a third determining module 404, configured to calculate a second braking torque limit value according to the at least one functional safety characterizing signal if the result of the determining module 402 is negative, and determine that the second braking torque limit value is the braking torque limit value of the vehicle.

In the embodiment, the first braking torque limit value is judged by using at least one functional safety representation signal, so that the monitoring of the first braking torque limit value is realized, the functional safety representation signal can represent the whole vehicle functional safety, if the first braking torque limit value is judged to be correctly calculated according to the functional safety representation signal, the first braking torque limit value can be determined to be reasonably set, and the first braking torque limit value can be used for limiting the braking torque, so that the driving safety is ensured; if the first braking torque limit value is judged to be calculated incorrectly according to the functional safety representation signal, the first braking torque limit value can be determined to be unreasonably set, and the driving safety can be damaged. By monitoring the braking torque limit value, the braking torque is limited by using a reasonable braking torque limit value, the situations of unexpected deceleration of the whole vehicle or unexpected reverse movement of the whole vehicle and the like are avoided, and the driving safety is ensured.

The brake control apparatus shown in fig. 4 can execute the brake control method described in the embodiment shown in fig. 1, and the implementation principle and technical effect are not described again.

In some embodiments, the determining module 402 may be specifically configured to determine whether the at least one functional safety indicator is a false verification and the first braking torque limit is a negative value.

In some embodiments, the determining module 402 may be specifically configured to determine whether the first braking torque limit value is a negative value, and at least one functional safety representation signal of the braking torque, the motor fault level, the vehicle speed, the operation mode, and the braking state satisfies a respective corresponding determination condition.

In some embodiments, the at least one functional safety characteristic signal may include a brake torque, and the determining module 402 may be specifically configured to determine whether the brake torque at which the first brake torque limit is calculated does not match the brake torque requested by the vehicle, and the first brake torque limit is a negative value.

In some embodiments, the at least one functional safety characteristic signal may include a motor fault level, and the determining module 402 may be specifically configured to determine whether the motor fault level reaches a preset fault level, and the first braking torque limit value is a negative value.

In some embodiments, the at least one functional safety characterizing signal may include a vehicle speed, and the determining module 402 may be specifically configured to determine whether the vehicle speed is less than a preset vehicle speed threshold, and the first brake torque limit value is a negative value.

In some embodiments, the at least one functional safety-characterizing signal may include an operating mode, and the determining module 402 may be specifically configured to determine whether the operating mode is a preset mode and the first brake torque limit is a negative value.

In some embodiments, the at least one functional safety-characterizing signal may include a braking state, and the determining module 402 may be specifically configured to determine whether a duration of the braking state is less than a preset braking time, and the first braking torque limit value is a negative value.

In some embodiments, the determining module 402 may be further configured to calculate a second braking torque limit value according to the at least one functional safety characterizing signal if the checking result of the at least one functional safety characterizing signal is correct and the first braking torque limit value is a negative value; and judging whether the difference value between the second braking torque limit value and the first braking torque limit value is smaller than a preset difference value threshold value.

The specific manner in which the brake control apparatus in the above-described embodiment performs the operation has been described in detail in the embodiment related to the method, and will not be described in detail here.

As shown in fig. 5, a schematic structural diagram of an embodiment of a vehicle body controller provided in the present application includes a storage component 501 and a processing component 502;

the storage component 501 may store one or more computer instructions for the processing component 502 to invoke for execution;

the processing component 502 can be configured to:

determining at least one functional safety representation signal and a first brake torque limit value of the vehicle, wherein the first brake torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety level;

judging whether the first braking torque limit value is correct or not according to at least one functional safety representation signal;

if not, calculating a second braking torque limit value according to the at least one function safety representation signal, and determining the second braking torque limit value as the braking torque limit value of the vehicle.

The vehicle body controller shown in fig. 5 may execute the braking control method described in the embodiment shown in fig. 1, and details of the implementation principle and the technical effect are not repeated.

The processing component 502 may include one or more processors executing computer instructions to perform all or part of the steps of the method described above. Of course, the processing elements may also be implemented as one or more Application Specific Integrated Circuits (ASICs), digital Signal Processors (DSPs), digital Signal Processing Devices (DSPDs), programmable Logic Devices (PLDs), field Programmable Gate Arrays (FPGAs), controllers, micro-controllers, microprocessors, or other electronic components configured to perform the above-described methods.

The storage component 501 is configured to store various types of data to support operations at the terminal. The storage component may be implemented by any type or combination of volatile or non-volatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks.

Of course, the body controller can of course also comprise other components, such as input/output interfaces, communication components, etc.

The input/output interface provides an interface between the processing components and peripheral interface modules, which may be output devices, input devices, etc.

The communication component is configured to facilitate wired or wireless communication between the body controller and other devices, and the like.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment may be implemented by software plus a necessary general hardware platform, and may also be implemented by hardware. Based on the understanding, the above technical solutions substantially or otherwise contributing to the prior art may be embodied in the form of a software product, which may be stored in a computer-readable storage medium, such as ROM/RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method according to the various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.

Claims

1. A brake control method characterized by comprising:

determining at least one functional safety characteristic signal of the vehicle and a first brake torque limit value, wherein the first brake torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety grade;

2. The method according to claim 1, characterized in that the at least one functional safety characteristic signal comprises a verification result of the at least one functional safety characteristic signal, the verification result being obtained by end-to-end verification of the at least one functional safety characteristic signal;

said determining whether said first brake torque limit is correct based on said at least one functional safety characterization signal comprises:

and judging whether the verification result of the at least one functional safety representation signal is wrong or not, wherein the first braking torque limit value is a negative value, if so, determining that the first braking torque limit value is incorrect, and otherwise, determining that the first braking torque limit value is correct.

3. The method of claim 1, wherein the at least one functional safety token signal comprises at least one of a brake torque, a motor fault level, a vehicle speed, an operating mode, a brake status;

said determining whether said first brake torque limit is correct based on said at least one functional safety characterizing signal comprises:

and judging whether the first braking torque limit value is a negative value or not, and at least one functional safety representation signal of the braking torque, the motor fault grade, the vehicle speed of the whole vehicle, the running mode and the braking state meets respective corresponding judgment conditions, if so, determining that the first braking torque limit value is incorrect, otherwise, determining that the first braking torque limit value is correct.

4. The method of claim 3, wherein the at least one functional safety characteristic signal comprises a braking torque;

judging whether the first braking torque limit value is a negative value or not, and judging whether at least one functional safety representation signal of the braking torque, the motor fault level, the whole vehicle speed, the running mode and the braking state meets respective corresponding judgment conditions comprises the following steps:

and judging whether the braking torque of the first braking torque limit value is not matched with the braking torque requested by the vehicle, wherein the first braking torque limit value is a negative value.

5. The method of claim 3, wherein the at least one functional safety characterizing signal comprises a motor fault level;

and judging whether the motor fault level reaches a preset fault level, wherein the first braking torque limit value is a negative value, and the motor at the preset fault level stops braking.

6. The method of claim 3, wherein the at least one functional safety-characterizing signal includes vehicle speed;

judging whether the first braking torque limit value is a negative value or not, and judging whether at least one functional safety representation signal in the braking torque, the motor fault level, the whole vehicle speed, the running mode and the braking state meets the respective corresponding judgment condition comprises the following steps:

7. The method of claim 3, wherein the at least one functional safety characterizing signal comprises a running mode;

8. The method of claim 3, wherein the at least one functional safety characterizing signal comprises a braking state;

and judging whether the duration time of the braking state is less than the preset braking time or not, and the first braking torque limit value is a negative value.

9. The method according to claim 1, characterized in that the at least one functional safety characteristic signal comprises a verification result of the at least one functional safety characteristic signal, the verification result being obtained by end-to-end verification of the at least one functional safety characteristic signal;

if the verification result of the at least one functional safety representation signal is correct and the first brake torque limit value is a negative value, calculating a second brake torque limit value according to the at least one functional safety representation signal;

10. The method of claim 1, wherein the second brake torque limit is 0 newton-meters.

11. A brake control apparatus, characterized by comprising:

the first determining module is used for determining at least one functional safety representation signal of the vehicle and a first brake torque limit value, and the first brake torque limit value is obtained through calculation according to the at least one functional signal; the functional safety characterization signal is a signal which is related to vehicle braking and has a functional safety level;

12. A vehicle body controller is characterized by comprising a storage component and a processing component;

the processing component, when invoking the computer instructions, performs the braking control method of any one of claims 1 to 10.