CN112918484A

CN112918484A - Vehicle brake system control method and device

Info

Publication number: CN112918484A
Application number: CN202110297769.4A
Authority: CN
Inventors: 陈磊; 梁帅
Original assignee: Beijing CHJ Automobile Technology Co Ltd
Current assignee: Beijing CHJ Automobile Technology Co Ltd
Priority date: 2021-03-19
Filing date: 2021-03-19
Publication date: 2021-06-08
Anticipated expiration: 2041-03-19
Also published as: CN112918484B

Abstract

The application provides a vehicle brake system control method and device, and the method comprises the following steps: acquiring a current braking efficiency factor of a vehicle braking system, wherein the current braking efficiency factor is determined in real time according to the state of the vehicle braking system; and controlling the brake system to act according to the current brake efficiency factor so as to realize wheel braking. The vehicle braking system control method provided by the application obtains current braking effectiveness factors representing the performance characteristics of the vehicle braking system in real time, and determines how to realize wheel braking based on the current braking effectiveness factors. Because the current braking effectiveness factor is determined in real time according to the state of the vehicle braking system, the control quantity determined by adopting the method can better reach the corresponding control target, so that the vehicle control is more accurate.

Description

Vehicle brake system control method and device

Technical Field

The application relates to the technical field of vehicle control, in particular to a vehicle braking system control method and device.

Background

Since the braking effectiveness factor directly represents the braking effectiveness of the Brake, it is used in an anti-lock braking System (ABS), a Traction Control System (TCS), a Vehicle Dynamic Control System (VDC), and automatic driving Control software. In particular applications, each of the aforementioned systems requires calculation of a brake control strategy based on the brake effectiveness factor and other parameters to achieve a predetermined vehicle control objective.

Currently, the brake performance factor is determined by test calibration (or directly from relevant parameters provided by the supplier) after the vehicle brakes are finalized, and written into the aforementioned program code, such as the brake control software; in vehicle applications, the brake effectiveness factor does not change.

When the vehicle is in use, the actual braking effectiveness of the brake is dynamically changed along with the performance degradation of the brake, and is not matched with the factory-calibrated brake effectiveness factor.

Disclosure of Invention

In order to solve the technical problems described above or at least partially solve the technical problems, the present application provides a vehicle brake system control method and apparatus.

In one aspect, the present application provides a vehicle brake system control method, including:

acquiring a current braking efficiency factor of a vehicle braking system, wherein the current braking efficiency factor is determined in real time according to the state of the vehicle braking system;

and controlling the brake system to act according to the current brake efficiency factor so as to realize wheel braking.

Optionally, before obtaining the current braking effectiveness factor of the vehicle braking system, the method further comprises:

obtaining the braking acceleration of a vehicle during braking and the braking pressure of the braking system;

calculating the current brake effectiveness factor based on the brake acceleration, the brake pressure, a wheel radius, and a vehicle mass.

Optionally, the vehicle comprises an energy recovery device;

calculating the current brake performance factor from the brake acceleration, the brake pressure, a wheel radius, and a vehicle mass, comprising:

acquiring a recovered braking torque formed by recovering energy by an energy recovery device when a vehicle is braked;

and calculating the current dynamic efficiency factor by adopting a first calculation method according to the braking acceleration, the braking pressure, the wheel radius, the vehicle mass and the recovered braking torque.

Optionally, the vehicle comprises an energy recovery device;

determining the recovery acceleration according to the recovery braking torque; the recovered acceleration is a vehicle acceleration resulting from the energy recovery device recovering energy;

and calculating the current dynamic efficiency factor by adopting a second calculation method according to the braking acceleration, the braking pressure, the wheel radius, the vehicle mass and the recovery acceleration.

Optionally, determining a recovery acceleration from the recovery braking torque comprises:

inquiring the corresponding relation between the recovered braking torque and the recovered acceleration according to the recovered braking torque, and determining the recovered acceleration;

the corresponding relation is corrected in real time according to the measured braking torque and the vehicle acceleration when only the energy recovery device is used for braking.

Optionally, the vehicle includes n braking devices, the current braking effectiveness factor includes a current braking effectiveness sub-factor corresponding to each braking device, and n is greater than or equal to 2;

obtaining the braking acceleration when the vehicle brakes and the braking pressure of the braking system, comprising: the method comprises the steps of obtaining braking acceleration at n moments and braking pressure of each braking device at corresponding moments, wherein the ratio of the braking pressure of each braking device at any two moments is different;

calculating the current brake performance factor from the brake acceleration, the brake pressure, a wheel radius, and a vehicle mass, comprising: and calculating each current braking effectiveness sub-factor according to the braking acceleration at n moments, the braking pressure of each braking device at the corresponding moment, the wheel radius and the vehicle mass.

Optionally, calculating each of the current brake effectiveness sub-factors according to the brake acceleration at n times, the brake pressure of each of the brake devices at the corresponding time, the wheel radius, and the vehicle mass, includes:

respectively constructing a sub-factor relation equation according to the braking acceleration at each moment, the braking pressure of each braking device at the corresponding moment, the wheel radius and the vehicle mass;

and calculating each current braking efficiency sub-factor according to the sub-factor relation equation corresponding to the n moments.

Optionally, calculating the current brake effectiveness factor from the brake acceleration, the brake pressure, a wheel radius, and a vehicle mass comprises:

acquiring a previous braking efficiency factor;

calculating a dynamic efficiency factor according to the braking acceleration, the braking pressure, the wheel radius and the vehicle mass;

calculating the current braking efficiency factor based on the previous braking efficiency factor and the dynamic efficiency factor.

Optionally, calculating the current braking efficiency factor from the previous braking efficiency factor and the dynamic efficiency factor comprises:

calculating a difference between the dynamic performance factor and the prior braking performance factor;

under the condition that the difference is not 0, calculating a factor correction value according to the difference and a preset coefficient, wherein the preset coefficient is less than 1;

calculating the current braking efficiency factor according to the previous braking efficiency factor and the factor correction value;

the control method further comprises the following steps: updating the prior braking effectiveness factor with the current braking effectiveness factor.

In another aspect, the present application provides a vehicle brake system control apparatus including:

the current braking effectiveness factor query unit is used for acquiring the current braking effectiveness factor of the vehicle braking system, and the current braking effectiveness factor is determined in real time according to the state of the vehicle braking system;

and the brake control unit is used for controlling the brake system to act according to the current brake efficiency factor so as to realize wheel braking.

Optionally, the method further comprises:

the system comprises a preceding parameter acquisition unit, a brake pressure acquisition unit and a control unit, wherein the preceding parameter acquisition unit is used for acquiring brake acceleration when a vehicle brakes and brake pressure of a brake system;

and the current braking effectiveness factor calculation unit is used for calculating the current braking effectiveness factor according to the braking acceleration, the braking pressure, the wheel radius and the vehicle mass.

Optionally, the vehicle comprises an energy recovery device;

the control device also comprises a recovery braking torque acquisition unit, a braking torque recovery unit and a braking torque recovery unit, wherein the recovery braking torque acquisition unit is used for acquiring the recovery braking torque formed by the energy recovery of the energy recovery device when the vehicle is braked;

the current braking efficiency factor calculating unit calculates the current braking efficiency factor by adopting a first calculating method according to the braking acceleration, the braking pressure, the wheel radius, the vehicle mass and the recovered braking torque; or,

the current braking efficiency factor calculating unit determines a recovery acceleration according to the recovery braking torque, and calculates the current braking efficiency factor by adopting a second calculating method according to the braking acceleration, the braking pressure, the wheel radius, the vehicle mass and the recovery acceleration;

the recovered acceleration is a vehicle acceleration resulting from the energy recovery device recovering energy.

the preceding parameter acquiring unit is used for acquiring the braking acceleration at n moments and the braking pressure of each braking device at corresponding moments, and the ratio of the braking pressure of each braking device at any two moments is different;

the current braking effectiveness factor calculating unit is configured to calculate each current braking effectiveness sub-factor according to the braking acceleration at n times, the braking pressure of each braking device at a corresponding time, and the wheel radius.

Optionally, the current braking effectiveness factor calculation unit includes:

an acquisition subunit for acquiring a preceding braking effectiveness factor;

a dynamic performance factor calculating subunit for calculating a dynamic performance factor based on the braking acceleration, the braking pressure, the wheel radius, and the vehicle mass;

a correction subunit for calculating the current braking effectiveness factor according to the previous braking effectiveness factor and the dynamic effectiveness factor;

an updating subunit, configured to update the previous braking effectiveness factor with the current braking effectiveness factor.

The vehicle braking system control method provided by the application obtains current braking effectiveness factors representing the performance characteristics of the vehicle braking system in real time, and determines how to realize wheel braking based on the current braking effectiveness factors. Because the current braking effectiveness factor is determined in real time according to the state of the vehicle braking system, the control quantity determined by adopting the method can better reach the corresponding control target, so that the vehicle control is more accurate.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art to obtain other drawings without inventive labor;

FIG. 1 is a schematic structural diagram of a vehicle brake provided in an embodiment of the present application;

FIG. 2 is a flow chart of a method for determining vehicle braking control provided by an embodiment of the present application;

FIG. 3 is a flowchart providing steps for determining a current braking effectiveness factor according to embodiments of the present application;

FIG. 4 is a flow chart of a method of calculating a current braking effectiveness factor provided by another embodiment of the present application;

FIG. 5 is a flow chart of a method of calculating a current braking effectiveness factor provided by another embodiment of the present application;

FIG. 6 is a schematic flow chart illustrating a process for calculating a braking effectiveness factor of at least two braking devices according to an embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of a vehicle brake system control device according to an embodiment of the present application;

FIG. 8 is a schematic structural diagram of a vehicle according to an embodiment of the present application

Fig. 9 is a schematic structural diagram of an electronic device provided in an embodiment of the present application;

wherein: 01-brake master cylinder, 02-brake body, 021-brake piston, 022-friction plate, 023-friction fit part, 11-current brake performance factor query unit, 12-brake control unit, 13-previous parameter acquisition unit, 14-current brake performance factor calculation unit, 21-processor, 22-brake, 221-brake piston, 222-friction plate, 223-brake fit part, 224-pressure sensor, 31-processor, 32-memory, 33-communication interface, 34-bus system.

Detailed Description

In order that the above-mentioned objects, features and advantages of the present application may be more clearly understood, the solution of the present application will be further described below. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, but the present application may be practiced in other ways than those described herein; it is to be understood that the embodiments described in this specification are only some embodiments of the present application and not all embodiments.

The embodiment of the application provides a vehicle braking system control method, which is used for braking control of a vehicle by adopting a vehicle braking effectiveness factor determined in real time.

Before describing the embodiments provided in the present application, an analysis of the structure of the vehicle brake system will be first performed, and then the meanings of some terms in the embodiments of the present application will be described.

Fig. 1 is a schematic structural diagram of a vehicle brake provided in an embodiment of the present application. As shown in fig. 1, the vehicle brake system includes a master cylinder 01 and a brake 02, and the brake 02 includes a brake piston 021, a friction plate 022, and a friction-fit portion 023 rigidly connected to wheels (the friction-fit portion 023 is a brake drum in the case where the brake 02 is a drum brake, and the friction-fit portion 023 is a brake disc in the case where the brake body 02 is a disc brake).

During braking, brake fluid (brake fluid is brake fluid or high-pressure gas) in the brake master cylinder 01 flows into a piston cavity of a brake piston 021 of the brake 02 to push the brake piston 021 to drive a friction plate 022 to press a brake matching part, the brake matching part moves relative to the friction plate 022 to generate friction force and generate brake torque based on the friction force, and under the condition that the brake torque generated by the friction plate is the same as the brake torque generated by ground friction force, the vehicle tire continues to roll and slide, but the kinetic energy of the vehicle is consumed to reduce the vehicle speed.

In the embodiment of the present application, the braking effectiveness factor is a parameter for representing the braking capability of the brake 02, and represents the ratio between the braking torque formed after braking and the braking force on the brake piston 021; it can be seen that the braking effectiveness factor is a parameter having a length dimension if strictly in accordance with the preceding definition.

In practice, since the configuration of the brake 02 is determined, the brake performance factor (brake performance factor is the ratio of the input brake pressure to the friction force generated by the brake) can be determined in comparison to a parameter indicative of the moment arm of the application of friction force. Thus, in some applications of embodiments of the present application, the brake effectiveness factor may be equivalently used as the brake effectiveness factor.

It should be noted that in the implementation of the embodiment of the present application, the braking effectiveness factor can be obtained only under specific conditions, specifically: the brake 02 does not lock the tire, and the wheel and the ground are in a state of rolling and sliding; if in a vehicle equipped with an anti-lock braking system, the aforementioned specific conditions are embodied in that the anti-lock braking system is not activated, the brake piston pushes the friction pads all the way close to the brake disc or the brake drum.

FIG. 2 is a flowchart of a method for determining braking control of a vehicle according to an embodiment of the present disclosure. As shown in fig. 2, a vehicle braking control method according to an embodiment of the present application includes steps S101-S102.

S101: a current braking effectiveness factor of a vehicle braking system is obtained.

In the embodiment of the application, the current braking effectiveness factor of the vehicle braking system is an effectiveness factor representing the current braking system state of the vehicle braking system, and is determined in real time according to the state of the vehicle braking system.

It should be noted that the aforementioned current brake effectiveness factor is determined in real time based on the state of the vehicle braking system and should be reasonably understood; in a specific application, determining the current braking effectiveness factor in real time may refer to calculating the current braking effectiveness factor at a certain time interval, and the braking effectiveness of the brake (i.e., the braking system) changes significantly within the certain time interval.

S102: and controlling the action of the braking system according to the current braking efficiency factor to realize wheel braking.

The method comprises the steps of determining the brake pressure applied to each brake in the brake system based on the current brake efficiency factor so that each brake master cylinder pushes a friction plate and a friction matching part to generate friction force according to the set brake pressure, and then generating brake torque due to the friction force to brake the corresponding wheel.

The aforementioned braking of the wheels may be used to decelerate the vehicle, or may be used to implement traction control, vehicle dynamic stability control, and other functions that need to be implemented based on braking system control.

As can be seen from the foregoing steps S101 and S102, the vehicle braking system control method according to the embodiment of the present application obtains the current braking effectiveness factor that represents the performance characteristic of the vehicle braking system in real time, and determines how to implement wheel braking based on the current braking effectiveness factor.

Because the current braking effectiveness factor is determined in real time according to the state of the vehicle braking system, the control quantity determined by adopting the method can better reach the corresponding control target, so that the vehicle control is more accurate.

The control method for the vehicle braking system according to the embodiment of the present application further includes a step of determining the current braking effectiveness factor, in addition to the steps of controlling the braking of the wheel by using the current braking effectiveness factor in the aforementioned steps S101-S102.

FIG. 3 is a flowchart providing steps for determining a current braking effectiveness factor according to embodiments of the present application; as shown in fig. 3, in the embodiment of the present application, the step of determining the current braking effectiveness factor includes steps S103-S104; it should be noted that steps S103-S104 are performed before step S101.

S103: the braking acceleration of the vehicle during front braking and the braking pressure of the braking system are obtained.

The preceding braking in step S103 is braking at a time before the control execution system in step S102 is operated. The braking action at the time of front braking is such that the vehicle generates deceleration, that is, such that the vehicle generates braking acceleration. In the embodiment of the present application, the braking acceleration is a deceleration during braking of the vehicle (for the sake of complying with the standard expression, the deceleration at the time of braking of the vehicle is referred to as braking acceleration here). In practical applications, the braking acceleration can be obtained as follows.

(1) In the case where a wheel speed sensor is mounted on a vehicle, wheel speed data detected by the wheel speed sensor is acquired, and a differential operation is performed based on the wheel speed data to obtain a braking acceleration.

(2) In the case where the vehicle is equipped with an acceleration sensor, acceleration data generated by the acceleration sensor is acquired, and the braking acceleration of the vehicle is determined based on the specific acceleration data.

In the embodiment of the application, the pressure sensor is arranged in the braking system, and the braking pressure of the braking system can be determined according to the braking pressure data detected by the pressure sensor.

In order to ensure data matching and effectiveness, in practical application, braking acceleration and braking pressure are mostly obtained when a vehicle brakes stably. For example, it is possible to determine whether the vehicle is in a smooth braking state according to whether the braking pressure is constant and/or whether the braking acceleration is constant, and if it is determined that the vehicle is in a smooth braking state, the braking acceleration and the braking pressure at that time are used.

In the embodiment of the present application, the brake pressure may be the pressure in the master cylinder 01 in fig. 1 or the brake pressure in the brake piston in fig. 1, according to different situations, and is analyzed according to the situations.

S104: the current braking effectiveness factor is calculated based on the braking acceleration, the braking pressure, the wheel radius and the vehicle mass.

In the embodiment of the application, the current braking efficiency factor adopts Eff_newAnd (4) showing. Current braking efficiency factor Eff_newIs a figure of merit characterizing the braking characteristics of the brake. Current braking efficiency factor Eff_newIs stored in the on-board unit system of the vehicle so that the vehicle brake control system is invoked.

As described above, when the vehicle is braked, the wheel is not in a locked state but in a rolling and sliding state, and the friction torque of the ground friction acting on the wheel is equal to the braking torque of the friction plate acting on the brake engagement portion. Therefore, the braking efficiency factor can be obtained from the friction torque based on the torque equality.

According to the F ═ ma, the magnitude of the friction braking force can be calculated according to the mass M of the vehicle and the braking acceleration a of the vehicle, and the moment arm corresponding to the friction braking force is the radius r of the wheel, so that the braking moment M acted on the wheel by the friction braking force is M × a × r.

The vehicle mass m may be set in advance or determined by measuring and calculating a vehicle travel-related parameter. For example, in one application, the vehicle mass m may be calculated based on the output torque of the vehicle powertrain, the wheel radius r, and the acceleration value during vehicle acceleration.

In practice, the wheel radius r may be determined by the user by filling in the relevant tables based on the tire size, or may be determined in other ways. For example, it can be determined by measuring the distance when the vehicle moves straight from one location to another and the number of turns of the wheel.

After obtaining the braking torque M, according to M-f_braker_break＝μF_braker_breakIn which F is_brakeFor brake pressure, r_breakThe moment arm is corresponding to the braking pressure; f_brakeCan be determined from the pressure sensor output data, then the current brake performance factor Eff is determined_new＝M÷F_brake. At r_breakIn a known manner, the brake performance factor can be directly used as the dynamic performance factor, i.e. the dynamic performance factor adopts the formula Eff_new＝M÷(F_brake×r_break) And (4) calculating.

As described above, in the foregoing embodiment, the value calculated using the braking acceleration, the braking pressure, the wheel radius, and the vehicle mass is directly used as the current braking effectiveness factor. In the embodiment of the present application, the calculation result may also be used as the dynamic performance factor Eff_Calc. Then, the dynamic efficiency factor and the preceding braking efficiency factor Eff are used_readObtaining the current braking efficiency factor Eff by comprehensive operation_new。

The prior brake performance factor is a historical brake performance factor stored in the on-board machine system; in particular, it is the braking efficiency factor for the braking of the vehicle that precedes the current braking efficiency factor, the previous braking efficiency factor characterizing the historical braking efficiency of the brake.

In one application of the embodiments of the present application, a dynamic efficiency factor Eff is employed_CalcAnd a preceding braking effectiveness factor Eff_readObtaining the current braking efficiency factor Eff_newIncludes S1041-S1043.

S1041: a prior braking effectiveness factor is obtained.

Obtaining a preceding braking effectiveness factor Eff_readCan be determined by reading the corresponding memory location of the vehicle memory.

S1042: a dynamic efficiency factor is calculated based on the brake acceleration, brake pressure, wheel radius, and vehicle mass.

As described above, the braking acceleration a and the braking pressure F are used_brakeCalculating dynamic efficiency factor Eff for wheel radius vehicle masses m and r_CalcMay be given by the formula of_Calc＝m×a×r÷F_brakeOr Eff_Calc＝m×a×r÷(F_brake×r_break)。

S1043: a current braking efficiency factor is calculated based on the previous braking efficiency factor and the dynamic efficiency factor.

In the embodiment specific application of the present application, the following A-D may be used depending on the preceding braking efficiency factor and the dynamic efficiency factor.

A: a difference between the dynamic efficiency factor and the prior braking efficiency factor is calculated.

The difference is expressed by Dev, then Dev ═ Eff_Calc-Eff_read|。

B: judging whether the difference value is 0; if yes, step C can be executed; if not, executing the step D.

C: the previous braking efficiency factor is used as the current braking efficiency factor.

D: calculating a factor correction value based on the difference and a preset coefficient, and then performing E.

In the embodiment of the present application, the preset coefficient is represented by a factor, and the preset coefficient factor is a coefficient smaller than 1, which can be determined according to the experience of the user and the update speed of the braking effectiveness factor acceptable to the user.

If the user intends to make the update degree of the current braking effectiveness factor faster, the preset coefficient may be set to be larger, for example, to 0.1; if the user intends to make the update degree of the current braking effectiveness factor slower, the preset coefficient may be set to a smaller value, for example, to 0.01.

In the embodiment of the application, the factor correction value is represented by Rev; according to step A, Rev ═ factor × Dev ═ factor × | Eff_Calc-Eff_read|。

E: a current braking effectiveness factor is calculated based on the previous braking effectiveness factor and the factor correction value.

In the embodiment of the application, the current braking efficiency factor is Eff_new＝Rev+Eff_read＝factor×|Eff_Calc-Eff_read|+Eff_read。

Calculating the current braking efficiency factor Eff by adopting the method determined by the S1041-S1043_newSo that the current braking efficiency factor Eff_newThe dynamic efficiency factor can be gradually approached based on the historical value, and the problem that the current braking efficiency factor is suddenly changed in use is avoided.

In addition, the method can also avoid the too fast change of data caused by inaccurate vehicle data, but the updated braking efficiency factor can be updated to be in accordance with the actual state characteristic of the brake after long-time use.

In a specific application of the embodiment of the present application, the foregoing steps S103 to S104 are executed periodically, and the processing frequency is set according to the operating characteristics of the in-vehicle system.

In order to adapt to the processing frequency set in the car machine system and avoid the problem that the braking efficiency factor is greatly changed in a short period of time due to the excessively fast processing frequency, the embodiment of the present application may further include, in addition to the foregoing steps a to E, step F: and acquiring a calculation period.

The calculation Period is a Period for executing single operation in the vehicle machine system to obtain the current braking efficiency factor, and the processing Period is expressed by Period.

Correspondingly, the aforementioned step D is refined as: and calculating the factor correction value according to the difference value, the preset coefficient and the calculation period.

As stated above, the factor correction value is Rev factor × period × Dev factor × period × Eff_Calc-Eff_read|。

It is conceivable that the Rev value is small if the calculation period is short (e.g., 0.02 s); the Rev value is larger if the calculation period is longer (e.g., 1 s).

Under the condition of introducing a calculation cycle, the braking efficiency factor correction value in each processing can be dynamically adjusted according to the operation processing frequency of the vehicle machine system, so that the change of the current braking efficiency factor is not too fast.

In addition, in the embodiment of the present application, the aforementioned determination of the current braking effectiveness factor Eff_newAfter step S1043, in order to make the previous braking effectiveness factor conform to the previous braking effectiveness of the braking system, step S1044 may be further included: the current braking effectiveness factor is used to update the previous braking effectiveness factor. In a specific application, the current braking efficiency factor is adopted to update the prior braking efficiency factor Eff_readI.e. the current braking efficiency factor Eff_newStored in the on-board unit system of a vehicle, replacing a preceding braking effectiveness factor Eff_read。

According to the vehicle braking system control method provided by the embodiment of the application, the braking efficiency factor stored in the vehicle machine system changes according to the actual characteristic change of the brake, so that the braking efficiency factor can be matched with the actual characteristic of the brake, and a braking control strategy based on braking efficiency factor planning has higher accuracy.

The method for determining the current braking efficiency factor mentioned in the foregoing embodiment is a method for determining the current braking efficiency factor in the case where the vehicle uses only brakes, and may be applied to a vehicle that uses only a conventional fuel engine as a power source and is not provided with an energy recovery device such as an energy recovery motor, or a new energy automobile that does not use energy recovery.

At present, in applications such as hybrid electric vehicles, pure electric vehicles and extended range vehicles, besides braking by using a brake, energy recovery by using a motor can be used for realizing braking; in order to achieve such vehicle braking effectiveness factor calculations, additional embodiments are provided.

Fig. 4 is a flowchart of a method for calculating a current braking effectiveness factor according to another embodiment of the present application. As shown in fig. 4, in the case where the vehicle is equipped with an energy recovery device, the method of determining the braking effectiveness factor includes steps S201 to S203.

S201: the braking acceleration of the vehicle during front braking, the braking pressure of a braking system and the recovery braking torque formed by the energy recovery device recovering energy are obtained.

The method for acquiring the braking acceleration and the braking pressure is the same as that in step S103, and will not be repeated here.

The recovered braking torque formed by the energy recovered by the energy recovery device can be obtained by directly searching the recovered braking torque acquired by the vehicle control system. In practice, the regenerative braking torque may be determined based on the actual sensed energy recovery device output torque, and the transmission efficiency between the energy recovery device and the wheel as determined by the previous bench test.

S202: a first calculation method is used to calculate a dynamic efficiency factor based on the braking acceleration, the braking pressure, the vehicle mass, the wheel radius and the recovered braking torque.

In the embodiment of the application, M is adopted for recovering the braking torque_retrieveAnd (4) showing.

The first calculation method may be as follows: calculating to obtain integral braking torque M as M × a × r, and subtracting recovered braking torque M from braking torque M_retrieveObtaining the braking torque M corresponding to the brake_brakeFinally, Eff is adopted_Calc＝M_brake÷F_brakeOr Eff_Calc＝M_brake÷(F_brake×r_brake) Obtaining the dynamic performance factor.

In practical application, inThe vehicle is provided with at least two driving motors, and under the condition that each driving motor is used as a power recovery device, the recovery braking torque of each driving motor can be respectively obtained, and the braking torque M formed by a braking system is obtained by subtracting each recovery braking torque from the braking torque M_brake。

S203: and obtaining the current braking efficiency factor according to the dynamic efficiency factor.

The specific implementation of step S203 is the same as the operation of step S104, and will not be repeated here. Of course, in some applications, the dynamic efficiency factor may also be used directly as the current braking efficiency factor.

By adopting the method provided by the embodiment of the application, the braking efficiency of the brake can be calculated under the condition that the brake and the power recovery device are used simultaneously.

Fig. 5 is a flowchart of a method for calculating a current braking effectiveness factor according to another embodiment of the present application. As shown in fig. 5, in the case where the vehicle is equipped with an energy recovery device, the method of determining the braking effectiveness factor includes steps S301 to S304.

S301: the braking acceleration of the vehicle during front braking, the braking pressure of a braking system and the recovery braking torque formed by the energy recovery device recovering energy are obtained.

The execution process of step S301 is the same as step S201, please refer to step S201.

S302: and determining the recovery acceleration according to the recovery braking torque.

The recovered acceleration is a vehicle acceleration resulting from the energy recovery device recovering energy; in the embodiment of the application, M is adopted for recovering the braking torque_retrieveIndicating that the recovered acceleration is taken as_retireveAnd (4) showing.

In the embodiment of the application, the recuperation braking torque developed by the energy recuperation device is not directly applied to the calculation of the dynamic performance factor, but is used first to determine the recuperation acceleration a_retireve. For determining the recovery acceleration a_retireveThe method of (3) is as follows.

(1) According to the recoveryBraking moment M_retrieveSearching historical driving data to obtain a recovered acceleration a_retireve。

During the running process of the vehicle, energy recovery can be realized only by adopting the energy recovery device to work according to the deceleration condition required to be achieved, and the brake system does not work.

At this time, a recovery acceleration a formed by recovering energy of the brake recovery apparatus may be determined based on the wheel speed information generated by the wheel speed sensor_retireveOr as recovered braking acceleration a based on data output from a vehicle acceleration sensor_retireve。

Recovery braking torque M of energy recovery device_retrieveCan be calculated by means of sensors, so that a recuperative braking torque M can be established_retrieveAnd recovering the acceleration a_retireveThe corresponding relation between them. By searching the corresponding relation, the braking torque M is recovered_retrieveThe recovery acceleration a can be determined_retireve。

In the embodiment of the present application, the corresponding relationship can be obtained by measuring the braking torque obtained when only the energy recovery device is used for braking (i.e. the recovered braking torque M formed by the operation of the energy recovery device)_retrieve) And vehicle acceleration a_retireveUpdating in real time; for example, to avoid causing recovery of the braking torque M of the vehicle due to accidental acquisition_retrieveAnd vehicle acceleration a_retireveThe corresponding relation does not conform to the actual situation, but the error caused by correcting the corresponding relation can be corrected, and in the actual application, a cyclic cumulative iteration method can be adopted according to the newly acquired recovery braking torque M_retrieveAnd vehicle acceleration a_retireveThe correspondence relationship is gradually corrected.

In the case where there is more than one energy recovery device and only the energy recovery device is used to determine the braking acceleration, the respective energy recovery devices may be operated alternately to determine the correspondence between the corresponding recovered braking torque and the braking acceleration. In practical application, the corresponding braking acceleration is respectively inquired according to the braking torque of each energy recovery braking device, and the braking accelerations are added to determine the actual recovery acceleration aretrieve.

(2) According to the recovery of braking torque M in the early-stage test process_retrieveAnd recovering the acceleration a_retireveDetermining the recovery acceleration a_retireve。

In some applications, the respective recovered brake torque M may be determined during a vehicle bench test_retrieveAnd recovering the acceleration a_retireveThe corresponding relationship of (a); during the running of the vehicle, M is obtained_retrieveThen, the corresponding relation can be searched to obtain the recovery acceleration a_retireve。

S303: a second calculation method is used to calculate a dynamic performance factor based on the braking acceleration, the recovered acceleration, the vehicle mass, and the wheel radius.

In the embodiment of the present application, M ═ mxa_retrieve×r+M_brakeCorrespondingly, the second calculation method may be as follows: eff_Calc＝(M-m×a_retrieve×r)÷F_brakeOr is Eff_Calc＝(M-m×a_retrieve×r)÷(F_brake×r_brake)。

S304: and obtaining the current braking efficiency factor according to the dynamic efficiency factor.

The specific implementation of step S304 is the same as the operation of step S104, and will not be repeated here.

Unlike the embodiment shown in fig. 4, in the embodiment of the present application, the dynamic performance factor is not directly calculated according to the recovered braking torque, but the recovery-induced scheduled acceleration is determined according to the recovered braking torque, and then the dynamic performance factor is calculated based on the recovered acceleration.

By adopting the method provided by the embodiment of the application, the vehicle speed change formed by the energy recovery device can be more accurately realized, and the calculated dynamic efficiency factor and the current braking efficiency factor are more accurate. The method for calculating the current brake performance factor provided in the foregoing embodiment calculates the overall current brake performance factor using the brake system of the vehicle as a whole, and the corresponding brake pressure may be the brake pressure measured at the master cylinder in fig. 1.

In practical applications, a braking system of a vehicle includes n braking devices, and each braking device operates independently in some cases, thus resulting in different braking effectiveness states, so that it is necessary to test a current braking effectiveness factor corresponding to each braking device, when the corresponding braking pressure needs to be measured at the brake piston in fig. 1, or in a pipe between the master cylinder and the brake piston.

For example, in some four-wheel vehicles, the front axle wheel uses a disc brake and the rear axle wheel uses a drum brake, and the braking factors of the front and rear axle brakes are different. In this case, the braking effectiveness factors of the different braking devices need to be calculated.

It should be noted that, in practical applications, the aforementioned braking device may refer to a brake on a wheel, or may be a braking device characterizing the same axle composed of two or more brakes on the same axle.

Fig. 6 is a schematic flowchart of a process for calculating braking effectiveness factors of at least two braking devices according to an embodiment of the present disclosure, and as shown in fig. 6, the present embodiment includes steps S401 to S403.

S401: the braking acceleration of n previous moments and the braking pressure of each braking device at the corresponding moment are obtained.

In the embodiment of the application, n is larger than or equal to 2, and the brake pressure ratio values of the brake devices at any two brake moments are different. In order to distinguish from the braking efficiency factor of the whole vehicle calculated in the previous embodiment, the dynamic efficiency factors corresponding to different braking devices in the embodiment of the present application are expressed by using dynamic efficiency sub-factors, and the corresponding identifier is Eff_calc1、Eff_calc2……。

n represents the number of updated current brake performance sub-factors that need to be calculated, which characterizes the current brake performance sub-factors of the n brake devices that need to be calculated separately.

In the foregoing, the difference between the braking pressure ratio of each braking device at any two braking moments is to ensure that n expressions with incompletely identical coefficients can be obtained in the subsequent steps to construct an equation set, so as to ensure that n dynamic performance sub-factors can be obtained through calculation.

S402: each dynamic performance sub-factor is calculated from the braking acceleration at n moments, the braking pressure of the respective braking device at the respective moment, the wheel radius and the vehicle mass.

The specific step S402 includes: respectively constructing a sub-factor relation equation according to the braking acceleration at each moment, the braking pressure of each braking device at the corresponding moment, the wheel radius and the vehicle mass; and then calculating each dynamic efficiency sub-factor according to the sub-factor relation equation corresponding to the n moments.

Following calculation of two current braking efficiency sub-factors Eff with the requirement for a four-wheeled vehicle (two-axle vehicle)_new1And Eff_new2This is described for the purpose of example. Here, a is adopted to correspond to the need to obtain the braking acceleration at two moments₁And a₂Indicating that the brake pressures of the two brake devices are respectively F at the first moment₁₁And F₁₂At the second moment, the brake pressures of the two brake devices are respectively F₂₁And F₂₂The friction braking torque of the ground friction force acting on the wheel at two moments is M₁And M₂。

Then M can be obtained₁＝Eff_calc1×F₁₁+Eff_calc2×F₁₂，M₂＝Eff_calc1×F₂₁+Eff_calc2×F₂₂The two equations described above form a system of linear equations in two dimensions. Having a unique solution condition according to a linear equation of two-fold, where F₁₁:F₁₂≠F₂₁:F₂₂Can find out Eff respectively_calc1And Eff_calc2。

In practical applications, in order to avoid causing problems in the calculation, in some practical applications, only F is used₁₁×F₂₂:F₁₂×F₂₁If the difference is greater than 1.1 or less than 0.9, the corresponding data is used for constructing the linear equation system, and the Eff is obtained through calculation_calc1And Eff_calc21。

By solving the binary linear equation set, the calculated dynamic performance sub-factor Eff can be obtained_calc1And Eff_calc2。

S403: and calculating the corresponding current braking efficiency sub-factor according to each dynamic efficiency sub-factor.

The specific implementation of step S403 is the same as that of step S1043, except that a plurality of corresponding current braking performance sub-factors need to be calculated in step S403.

In other applications of the embodiment of the present application, as in the foregoing step S104, the braking acceleration at n times, the braking pressure of each braking device at the corresponding time, the wheel radius, and the vehicle mass may also be directly used to calculate each current braking performance sub-factor.

It should be noted that, in practical applications, the steps corresponding to fig. 4 or fig. 5 may be merged with the steps in fig. 6 to realize the calculation of multiple braking effectiveness factors of the vehicle with the power recovery device, and specifically, the following (1) and (2) may be implemented.

(1) Acquiring a recovered braking torque, a braking acceleration, a wheel radius and a vehicle mass formed by recovering energy by a plurality of energy recovery devices at previous moments, and calculating a braking torque M according to the braking acceleration, the wheel radius and the vehicle braking; then, calculating according to the braking torque M and the recovered braking torque to obtain a corresponding friction braking torque, then constructing an equation set by adopting the friction braking torque and the braking pressure of a corresponding braking device, and calculating by utilizing the equation set to obtain a dynamic efficiency sub-factor; and finally, calculating to obtain each current braking efficiency sub-factor based on the dynamic efficiency sub-factors.

(2) Acquiring a recovered braking torque, a braking acceleration, a wheel radius and a vehicle mass which are formed by recovering energy by a plurality of energy recovery devices at previous moments; determining the recovery acceleration according to the recovery braking torque; determining the braking acceleration formed by the work of the braking device according to the braking acceleration and the recovery acceleration; then, calculating friction braking torque by adopting the braking acceleration, the vehicle mass and the wheel radius; constructing an equation set by adopting the friction braking torque and the braking pressure of the corresponding braking device, and calculating by utilizing the equation set to obtain a dynamic efficiency sub-factor; and finally, calculating to obtain each current braking efficiency sub-factor based on the dynamic efficiency sub-factors.

It should be noted that, in practical applications, the steps of calculating the current braking effectiveness factor determining method to obtain the braking acceleration and the braking pressure in the foregoing embodiments are all preferably the acceleration generated when the vehicle brakes when running on flat ground, so as to eliminate the problems of inaccurate acceleration measurement caused by the change of the posture of the vehicle on a slope as much as possible, and in practical tests, the vehicle should be in a straight running state as much as possible, so as to avoid errors caused by different speeds of the left and right wheels and different braking forces.

Of course, in some embodiments of the present application, if more sensors for data verification and ensuring accurate acquisition of the braking acceleration and the braking pressure are arranged in the vehicle, parameters such as the braking acceleration and the braking pressure may also be acquired under various working conditions of the vehicle.

In addition to providing the vehicle brake system control method, the embodiment of the application also provides a vehicle brake system control device.

Fig. 7 is a schematic structural diagram of a vehicle braking system control device provided in an embodiment of the present application, and as shown in fig. 7, the vehicle braking system control device provided in the embodiment of the present application includes a current braking effectiveness factor query unit 11 and a braking control unit 12.

The current braking effectiveness factor query unit 11 is used for obtaining a current braking effectiveness factor of the vehicle braking system.

The brake control unit 12 is configured to control the brake system to perform wheel braking according to the current braking performance factor.

The aforementioned wheel braking may be used to decelerate the vehicle, or may be used to implement traction control, vehicle dynamic stability control, and other functions that need to be implemented based on braking system control.

Because the current braking effectiveness factor is determined in real time according to the state of the vehicle braking system, the control quantity determined by the device can better reach the corresponding control target, so that the vehicle control is more accurate.

In a specific application of the embodiment of the present application, the vehicle brake system control apparatus further includes a previous parameter acquisition unit 13 and a current brake effectiveness factor calculation unit 14.

The preceding parameter acquiring unit 13 is used for acquiring the braking acceleration of the vehicle during the preceding braking and the braking pressure of the braking system.

In practical applications, the braking acceleration can be obtained as follows.

The current brake effectiveness factor calculation unit 14 is configured to calculate a current brake effectiveness factor based on the brake acceleration, the brake pressure, the wheel radius, and the vehicle mass.

In another application of the embodiment of the present application, the current braking effectiveness factor calculation unit includes an acquisition subunit, a dynamic effectiveness factor calculation subunit, and a modification subunit.

The acquisition subunit is configured to acquire a preceding braking effectiveness factor. Obtaining a preceding braking effectiveness factor Eff_readCan be determined by reading the corresponding memory location of the vehicle memory.

The dynamic efficiency factor calculating subunit is used for calculating the dynamic efficiency factor according to the braking acceleration, the braking pressure, the wheel radius and the vehicle mass.

As described above, the braking acceleration a and the braking pressure F are used_brakeVehicle wheel radius vehicle mass m and r meterComputational efficiency factor Eff_CalcMay be given by the formula of_Calc＝m×a×r÷F_brakeOr Eff_Calc＝m×a×r÷(F_brake×r_break)。

The correction subunit is configured to calculate a current braking effectiveness factor based on the previous braking effectiveness factor and the dynamic effectiveness factor.

In a specific application of the embodiment of the present application, the correction subunit may calculate the current braking effectiveness factor by using the following steps a to E.

The difference is expressed by Dev, then Dev ═ Eff_Calc-Eff_read|。

Calculating the current braking efficiency factor Eff by adopting the method_newSo that the current braking efficiency factor Eff_newThe dynamic efficiency factor can be gradually approached based on the historical value, and the problem that the current braking efficiency factor is suddenly changed in use is avoided.

In addition, in the embodiment of the present application, the aforementioned determination of the current braking effectiveness factor Eff_newThe step (b) is periodically repeated, and in order to make the previous braking effectiveness factor conform to the previous braking effectiveness of the braking system, the current braking effectiveness factor calculation unit further comprises an updating subunit for updatingThe subunit is configured to update the previous braking effectiveness factor with the current braking effectiveness factor.

In some applications of embodiments of the present application, the vehicle further comprises an energy recovery device.

Correspondingly, the control device also comprises a recovery braking torque acquisition unit, and the recovery braking torque acquisition unit is used for acquiring the recovery braking torque formed by the energy recovery device recovering energy when the vehicle is braked.

Accordingly, the method of calculating the dynamic performance factor by the current braking performance factor calculating unit 14 may include the following two methods.

(1) A first calculation method is used to calculate a dynamic efficiency factor based on the braking acceleration, the braking pressure, the wheel radius, the vehicle mass and the recovered braking torque.

The recovered braking torque formed by the energy recovered by the energy recovery device can be obtained by directly searching the recovered braking torque acquired by the vehicle control system. In practice, the recovered braking torque may be determined based on the actual sensed output torque of the energy recovery device, and the transmission efficiency between the energy recovery device and the wheel as determined by the previous bench test.

In one specific application, the first calculation method includes: calculating to obtain integral braking torque M as M × a × r, and subtracting recovered braking torque M from braking torque M_retrieveObtaining the braking torque M corresponding to the brake_brakeFinally, Eff is adopted_Calc＝M_brake÷F_brakeOr Eff_Calc＝M_brake÷(F_brake×r_brake) Obtaining the dynamic performance factor.

In practical application, under the condition that at least two driving motors are installed on a vehicle and each driving motor is used as a power recovery device, the recovered braking torque of each driving motor can be respectively obtained, and the braking torque M formed by a braking system is obtained by subtracting each recovered braking torque from the braking torque M_brake。

The dynamic performance factor calculating unit 14 then calculates the braking torque M_brakeAnd brake pressure calculation dynamicsA figure of merit.

(2) A recovery acceleration is determined from the recovery braking torque, and a dynamic efficiency factor is calculated using a second calculation method based on the braking acceleration, the braking pressure, the wheel radius, the vehicle mass, and the recovery acceleration.

In the exemplary embodiment, the recuperation braking torque generated by the energy recuperation device is not directly used for calculating the dynamic performance factor, but is used first for determining the recuperation acceleration a_retireve. For determining the recovery acceleration a_retireveThe method of (1) is as follows.

A. According to the recovered braking torque M_retrieveSearching historical driving data to obtain a recovered acceleration a_retireve。

In the embodiment of the present application, the corresponding relationship can be obtained by measuring the braking torque obtained when only the energy recovery device is used for braking (i.e. the recovered braking torque M formed by the operation of the energy recovery device)_retrieve) And vehicle acceleration a_retireveUpdating in real time; for example, to avoid causing recovery of the braking torque M of the vehicle due to accidental acquisition_retrieveAnd vehicle acceleration a_retireveThe corresponding relation does not conform to the actual situation, and is caused by correcting the corresponding relationIn practical application, the method of cycle accumulation iteration can be adopted to recover the braking torque M according to the latest collection_retrieveAnd vehicle acceleration a_retireveThe correspondence relationship is gradually corrected.

In the case where there is more than one energy recovery device and only the energy recovery device is used to determine the braking acceleration, the respective energy recovery devices may be operated alternately to determine the correspondence between the corresponding recovered braking torque and the braking acceleration. In practical application, the corresponding braking acceleration is respectively inquired according to the braking torque of each energy recovery braking device, and the actual recovery acceleration a is determined by adding the braking accelerations_retireve。

B. According to the recovery of braking torque M in the early-stage test process_retrieveAnd recovering the acceleration a_retireveDetermining the recovery acceleration a_retireve。

In one particular application, the second calculation method may be represented by the following formula:

Eff_Calc＝(M-m×a_retrieve×r)÷F_brakeor is Eff_Calc＝(M-m×a_retrieve×r)÷(F_brake×r_brake)。

In practical application of the embodiment of the application, the braking system comprises n braking devices, wherein n is more than or equal to 2, and the current braking efficiency factors of the braking devices are different. For example, in some four-wheel vehicles, the front axle wheel uses a disc brake and the rear axle wheel uses a drum brake, and the braking factors of the front and rear axle brakes are different. In this case, the current braking efficiency sub-factor of the different braking devices needs to be calculated. It should be noted that, in practical applications, the aforementioned braking device may refer to a brake on a wheel, or may be a braking device characterizing the same axle composed of two or more brakes on the same axle.

Correspondingly, the previous parameter obtaining unit 13 obtains the braking acceleration at n moments and the braking pressure of each braking device at n moments, and the ratio of the braking pressure of each braking device at any two moments is different;

the current braking effectiveness factor calculation unit 14 calculates each current braking effectiveness sub-factor based on the braking acceleration at n times, the braking pressure of each braking device at the corresponding time, and the wheel radius. In a specific application, the current braking effectiveness factor calculating unit 14 first constructs a sub-factor relation equation according to the braking acceleration at each moment, the braking pressure of each braking device at the corresponding moment, the wheel radius and the vehicle mass; and then calculating each current braking effectiveness sub-factor according to the sub-factor relation equation corresponding to the n moments.

In a specific application of the embodiment of the application, the current braking efficiency factor calculating unit calculates the dynamic efficiency sub-factor corresponding to each current braking efficiency sub-factor, and then calculates the corresponding current braking efficiency sub-factor based on the dynamic efficiency sub-factor.

In order to distinguish from the braking efficiency factor of the whole vehicle calculated in the previous embodiment, the dynamic efficiency factors corresponding to different braking devices in the embodiment of the present application are expressed by using dynamic efficiency sub-factors, and the corresponding identifier is Eff_calc1、Eff_calc2……。

In the foregoing, the difference between the braking pressure ratios of the braking devices at any two braking moments is to ensure that n formulas with incompletely identical parameter coefficients can be obtained in the subsequent steps, so as to ensure that n dynamic performance sub-factors can be obtained by calculation.

Subsequently, the current braking effectiveness sub-factor may be calculated based on the respective dynamic effectiveness sub-factors using the aforementioned method.

In addition to providing the aforementioned method and apparatus for determining a braking effectiveness factor, embodiments of the present application provide a vehicle. FIG. 8 is a schematic structural diagram of a vehicle according to an embodiment of the present application. The vehicle includes a braking system and a processor.

The brake system includes a master cylinder and a brake actuator 22, and the brake actuator 22 includes a brake piston 221, a friction plate 222 mounted on a free end of the brake piston 221, a brake engagement portion 223 engaged with the friction plate 222, and a pressure sensor 224 for a vehicle piston brake pressure.

The processor 23 is configured to execute the control method of the vehicle brake system as mentioned above, and control the vehicle brake system to operate.

The vehicle in the embodiment of the present application may be a two-wheeled vehicle or a four-wheeled or higher vehicle. In practical applications, the vehicle in the embodiment of the present application may be a conventional vehicle driven based on a heat engine, a pure electric vehicle or a range extender vehicle driven by an electric motor, or a vehicle driven by a heat engine and an electric motor in parallel (i.e. a hybrid vehicle).

In the case that the vehicle is a pure electric vehicle, a range-extended vehicle or a hybrid vehicle, the vehicle may further be configured with a device for acquiring the recovered braking torque, so as to be able to determine the recovered braking torque generated by recovering power by a power recovery device such as a motor, or to acquire the recovered acceleration determined based on the recovered braking torque, so that the processor can calculate the current braking effectiveness factor according to such parameters by the method provided in some embodiments in the foregoing.

The embodiment of the application also provides the electronic equipment.

Fig. 9 is a schematic structural diagram of an electronic device provided in an embodiment of the present application. As shown in fig. 9, the electronic device comprises at least one processor 31, at least one memory 32 and at least one communication interface 33.

The memory 32 in this embodiment may be a volatile memory or a non-volatile memory, or a combination of the two. In some embodiments, memory 32 stores the following elements: executable units or data structures, or a subset thereof, or an expanded set thereof: an operating system and an application program. The operating system includes various system programs, such as a framework layer, a core library layer, a driver layer, and the like, and is used for implementing various basic tasks and processing hardware-based tasks. And the application programs comprise application programs of various application tasks. The program for implementing the method for determining the braking effectiveness factor provided by the embodiment of the application can be included in the application program.

In the embodiment of the present application, the processor 31 executes the steps of the method for determining the braking effectiveness factor by calling a program or an instruction (specifically, a program or an instruction stored in an application program) stored in the memory 32.

In the embodiment of the present Application, the Processor 31 may be a general-purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, a discrete Gate or transistor logic device, or a discrete hardware component. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The steps of the method for determining the braking performance factor provided by the embodiment of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software units in the decoding processor. The software elements may be located in ram, flash, rom, prom, or eprom, registers, among other storage media that are well known in the art. The storage medium is located in the memory 32, and the processor 31 reads the information in the memory 32 and performs the steps of the method in combination with the hardware thereof.

The communication interface 33 is used for implementing information transmission between the intelligent driving control system and external devices, for example, to obtain various vehicle sensor data, and generate and issue corresponding control instructions to the vehicle actuator.

The memory and processor components in the electronic device are coupled together by a bus system 34, with bus system 34 being used to enable connective communication between these components. In the embodiment of the present application, the bus system may be a CAN bus, and may also be another type of bus. The bus system 334 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are labeled as bus system 34 in fig. 9.

The embodiments of the present application further provide a non-transitory computer-readable storage medium, where a program or an instruction is stored in the non-transitory computer-readable storage medium, and the program or the instruction causes a computer to execute the steps of the foregoing method for determining a braking performance factor, which are not described herein again to avoid repeated descriptions.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present application and are presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A vehicle brake system control method, characterized by comprising:

2. The vehicle brake system control method according to claim 1, further comprising, before obtaining the current braking effectiveness factor of the vehicle brake system:

3. The vehicle brake system control method according to claim 2, characterized in that the vehicle includes an energy recovery device;

4. The vehicle brake system control method according to claim 2, characterized in that the vehicle includes an energy recovery device;

determining the recovery acceleration according to the recovery braking torque;

5. The vehicle brake system control method according to claim 4, wherein determining a recovery acceleration in accordance with the recovery brake torque includes:

6. The vehicle braking system control method according to claim 2, wherein the vehicle includes n braking devices, the current braking effectiveness factor includes a current braking effectiveness sub-factor corresponding to each braking device, and n is greater than or equal to 2;

7. The vehicle brake system control method according to claim 6, wherein calculating each of the current brake performance sub-factors based on the braking acceleration at n times, the braking pressure of each of the brake devices at the corresponding time, the wheel radius, and the vehicle mass includes:

8. The vehicle braking system control method according to claim 2, wherein calculating the current braking effectiveness factor based on the braking acceleration, the braking pressure, a wheel radius, and a vehicle mass comprises:

acquiring a previous braking efficiency factor;

9. The vehicle brake system control method according to claim 8,

calculating the current braking efficiency factor from the previous braking efficiency factor and the dynamic efficiency factor, including:

under the condition that the difference is not 0, calculating a factor correction value according to the difference and a preset coefficient;

10. A vehicle brake system control device, characterized by comprising:

11. The vehicular brake system control device according to claim 10, characterized by further comprising:

12. The vehicle brake system control device according to claim 11, wherein the vehicle includes an energy recovery device;

13. The vehicle braking system control device according to claim 11, wherein the vehicle includes n braking devices, the current braking effectiveness factor includes a current braking effectiveness sub-factor corresponding to each braking device, and n is greater than or equal to 2;

14. The vehicular brake system control device according to claim 11, wherein the current braking effectiveness factor calculation unit includes:

an acquisition subunit for acquiring a preceding braking effectiveness factor;

a dynamic performance factor calculating subunit, configured to calculate a dynamic performance factor according to the braking acceleration, the braking pressure, a wheel radius, and a vehicle mass;

15. A vehicle comprising a braking system and a processor;

the processor is used for executing the vehicle brake system control method according to any one of claims 1 to 9, and controlling the brake system to act to realize vehicle braking.