Brake control method and device of brake-by-wire system, vehicle and medium

Abstract

The embodiment of the invention provides a brake control method and device of a brake-by-wire system, a vehicle and a medium, and the method comprises the steps that when a brake request is received, vehicle state information is obtained; the braking request has corresponding initial braking force; determining the whole vehicle mass and the road gradient based on the vehicle state information; determining a first correction coefficient based on the whole vehicle mass and / or the road slope; the initial braking force is corrected through the first correction coefficient, and target braking force is determined; and brake control is conducted based on the target brake force. According to the embodiment of the invention, the braking force can be corrected, the braking efficiency can be accurately output, and the comfort, safety and user experience of vehicle use are improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a braking control method of a wire-controlled brake system, a braking control device of a wire-controlled brake system, a vehicle and a computer-readable storage medium. Background Art

[0002] In the related art, there are several fixed curves of the relationship between target brake pressure and master cylinder push rod stroke in the brake control of the wire control brake system. Based on the detected pedal depth or pedal force, different target brake pressures or brake forces are determined by matching with the curve to control the brakes. However, drivers often control the pedal depth or pedal force according to their driving habits. When the external conditions of the vehicle change, the user presses the brake pedal according to habit, and the braking performance at this time may be insufficient or exceed expectations, affecting the comfort, safety and user experience of the vehicle. Summary of the invention

[0003] In view of the above problems, embodiments of the present application are proposed to provide a braking control method of a wire control brake system, a braking control device of a wire control brake system, a vehicle and a computer-readable storage medium that overcome the above problems or at least partially solve the above problems.

[0004] In order to solve the above problems, in a first aspect of the present application, an embodiment of the present application discloses a braking control method of a wire control brake system, comprising:

[0005] Upon receiving a braking request, obtaining vehicle state information; the braking request having a corresponding initial braking force;

[0006] Determine the vehicle mass and the road slope based on the vehicle state information;

[0007] Determining a first correction coefficient based on the vehicle mass and / or the road slope;

[0008] Correcting the initial braking force using the first correction coefficient to determine a target braking force;

[0009] Braking control is performed based on the target braking force.

[0010] Optionally, the vehicle state information includes vehicle acceleration, vehicle speed and output torque, and the step of determining the vehicle mass and road slope based on the vehicle state information includes:

[0011] determining a vehicle mass based on the vehicle acceleration and the output torque;

[0012] A road grade is determined based on the vehicle acceleration and the vehicle speed.

[0013] Optionally, the step of determining the vehicle mass based on the vehicle acceleration and the output torque comprises:

[0014] determining a vehicle driving force based on the output torque;

[0015] Establishing a first observation equation for the vehicle driving force and the vehicle acceleration;

[0016] The first observation equation is solved based on the recursive least square method to determine the vehicle mass.

[0017] Optionally, the step of determining the road slope based on the vehicle acceleration and the vehicle speed comprises:

[0018] determining a differential value of the vehicle speed;

[0019] Determining a Kalman filter state equation according to the differential value and a preset gravity acceleration;

[0020] The vehicle acceleration is filtered based on the Kalman filter equation to determine the road slope.

[0021] Optionally, the step of determining the first correction coefficient based on the vehicle mass and / or the road slope includes:

[0022] Determining a calibrated mass and a calibrated slope corresponding to the initial braking force;

[0023] If the vehicle mass does not match the calibrated mass, determining a mass correction factor based on the vehicle mass and the calibrated mass;

[0024] If the calibrated slope does not match the road slope, determining a slope correction factor based on the calibrated slope and the road slope;

[0025] The mass correction coefficient and / or the slope correction coefficient are determined as the first correction coefficient.

[0026] Optionally, the method further comprises:

[0027] Get the brake disc temperature;

[0028] determining a second correction factor based on the brake disc temperature;

[0029] The first correction coefficient and / or the second correction coefficient are used to correct the initial braking force to determine the target braking force.

[0030] Optionally, the step of correcting the initial braking force by using the first correction coefficient to determine the target braking force includes:

[0031] The target braking force is determined by combining the first correction coefficient and the initial braking force.

[0032] In a second aspect of the present application, an embodiment of the present application discloses a brake control device of a wire control brake system, comprising:

[0033] A first acquisition module is used to acquire vehicle state information when a braking request is received; the braking request has a corresponding initial braking force;

[0034] A first determination module, configured to determine a vehicle mass and a road slope based on the vehicle state information;

[0035] A second determination module, configured to determine a first correction coefficient based on the vehicle mass and / or the road slope;

[0036] A correction module, configured to correct the initial braking force using the first correction coefficient to determine a target braking force;

[0037] A control module is used to perform braking control based on the target braking force.

[0038] In the third aspect of the present application, an embodiment of the present application discloses a vehicle, including a processor, a memory, and a computer program stored in the memory and capable of running on the processor, wherein the computer program, when executed by the processor, implements the braking control method of the wire control brake system as described above.

[0039] In a fourth aspect of the present application, an embodiment of the present application discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the braking control method of the wire control brake system as described above is implemented.

[0040] The embodiments of the present application include the following advantages:

[0041] The embodiment of the present application detects the vehicle mass and the road slope of the road. When the external conditions such as the vehicle mass and the road slope change, the corresponding first correction coefficient can be determined to correct the initial braking force. When the user presses the brake pedal as usual, the braking force can be dynamically adjusted in real time based on the changed vehicle mass and road slope, so as to accurately output the braking efficiency and improve the comfort, safety and user experience of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a flowchart of a brake control method embodiment of a wire control brake system of the present application;

[0043] Figure 2 is a flowchart of another embodiment of a brake control method for a wire-controlled brake system of the present application;

[0044] Figure 3It is a schematic diagram of the relationship between the stroke and the braking force after the target braking force is corrected in an embodiment of a braking control method for a wire-controlled brake system of the present application;

[0045] Figure 4 is a flowchart of an example of a brake control method for a wire control brake system of the present application;

[0046] Figure 5 is a structural block diagram of an embodiment of a brake control device of a wire control brake system of the present application;

[0047] Figure 6 is a structural block diagram of a vehicle provided in an embodiment of the present application;

[0048] Figure 7 It is a structural block diagram of a storage medium provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0050] Reference Figure 1 , shows a flowchart of a braking control method of a wire-controlled brake system of the present application, wherein the braking control of the wire-controlled brake system may specifically include the following steps:

[0051] Step 101, when a braking request is received, obtaining vehicle state information; the braking request has a corresponding initial braking force;

[0052] When the driver needs to brake when the road condition changes while driving the vehicle, he can generate a braking request by stepping on the brake pedal. The braking request has a corresponding initial braking force, and the magnitude of the initial braking force can be related to the pedal depth or pedal force of the brake pedal. The greater the pedal depth or pedal force of the brake pedal, the greater the corresponding initial braking force; conversely, the smaller the pedal depth or pedal force of the brake pedal, the smaller the corresponding initial braking force.

[0053] When a braking request is received, vehicle status information may be obtained. The vehicle status information is used to represent the status of the vehicle itself detected by the sensor or data corresponding to the road status on which the vehicle is located.

[0054] Step 102, determining the vehicle mass and the road slope based on the vehicle state information;

[0055] The vehicle state information is analyzed to determine the vehicle mass and the road slope of the road the vehicle is on. The vehicle mass can be measured in kilograms, and the road slope can be measured in degrees.

[0056] Step 103, determining a first correction coefficient based on the vehicle mass and / or the road slope;

[0057] The first correction coefficient may be determined by using a change in the mass of the entire vehicle, or by using a change in the road slope, or may be determined based on changes in both.

[0058] Step 104, using the first correction coefficient to correct the initial braking force to determine a target braking force;

[0059] The initial braking force is corrected by using the first correction coefficient, and the obtained braking force is the target braking force. The target braking force can be the braking force of the vehicle or the oil pressure of the brake cylinder. The target braking force is used to represent the braking performance that the whole vehicle needs to achieve.

[0060] Step 105: Perform braking control based on the target braking force.

[0061] The target braking force is used to control the operation of the brake oil pump, wheel cylinder, piston or the actuation of the brake motor to achieve the braking efficiency corresponding to the target braking force and control the braking of the vehicle.

[0062] The embodiment of the present application detects the vehicle mass and the road slope of the road. When the external conditions such as the vehicle mass and the road slope change, the corresponding first correction coefficient can be determined to correct the initial braking force. When the user presses the brake pedal as usual, the braking force can be dynamically adjusted in real time based on the changed vehicle mass and road slope, so as to accurately output the braking efficiency and improve the comfort, safety and user experience of the vehicle.

[0063] Reference Figure 2 , shows a flowchart of another braking control method of a wire-controlled brake system of the present application, wherein the braking control of the wire-controlled brake system may specifically include the following steps:

[0064] Step 201, when a braking request is received, obtaining vehicle state information; the braking request has a corresponding initial braking force;

[0065] When the user steps on the brake pedal, an initial braking force corresponding to the pedal depth or pedal force is determined, and a brake request having the initial braking force is generated.

[0066] When a braking request is received, vehicle status information is obtained from various sensors, wherein the vehicle status information may include vehicle acceleration, vehicle speed, and output torque, wherein the output torque may be the output torque outputted externally by components such as an engine or a motor.

[0067] Step 202, determining the vehicle mass and the road slope based on the vehicle state information;

[0068] Based on the detected vehicle status information, the vehicle mass and road slope are calculated to determine the vehicle's current vehicle mass and road slope.

[0069] In an optional embodiment of the present application, the step of determining the vehicle mass and the road slope based on the vehicle state information includes:

[0070] Sub-step S2021, determining the vehicle mass based on the vehicle acceleration and the output torque;

[0071] The vehicle's current mass can be determined by the vehicle's acceleration and output torque.

[0072] Furthermore, the step of determining the vehicle mass based on the vehicle acceleration and the output torque includes: determining the vehicle driving force according to the output torque; establishing a first observation equation for the vehicle driving force and the vehicle acceleration; and solving the first observation equation based on the recursive least squares method to determine the vehicle mass.

[0073] The vehicle driving force can be determined based on the output torque, the efficiency of the transmission system and the transmission ratio. Based on the vehicle dynamics model, the first observation equation is established according to the vehicle driving force and the vehicle acceleration. Then, the recursive least squares method is used to solve the first observation equation to obtain the vehicle mass.

[0074] Specifically, the driving force equation of the output torque is:

[0075]

[0076] Where T tq The actual output torque; i0 is the transmission ratio; η T is the mechanical transmission efficiency; r is the wheel radius.

[0077] Vehicle dynamics model formula:

[0078]

[0079] The vehicle acceleration a is:

[0080]

[0081] Connecting formulas (1), (2) and (3), we can get the vehicle mass as:

[0082]

[0083] In the formula, m is the vehicle mass, F x is the driving force, f is the friction coefficient, C d Drag coefficient, A is the vehicle's positive projection area, and p is the atmospheric pressure.

[0084] Wherein, the rolling resistance and the air resistance are both obtained by looking up the resistance curve table, and the above formula (2) can be:

[0085] F x =f1+f2+ma (5)

[0086] Where f1 is rolling resistance, f2 is air resistance, and a is the acceleration of the vehicle. Usually, the mass of a car is a slow variable. Based on this feature, the recursive least squares method is used to calculate the mass of the car in real time:

[0087] m(k)=m(k-1)+K(k)[F(k)-x(k)m(k-1)](6)

[0088] P(k)=[IK(k)x(k)]P(k-1)(7)

[0089]

[0090] Where m(k) is the estimated value of the vehicle mass at the kth moment; m(k-1) is the estimated value of the vehicle mass at the k-1th moment; F(k) is the system driving force F at the kth moment x ; x(k) is the observable data vector, including constants, vehicle speed, etc.

[0091] The vehicle mass is calculated using formulas (6), (7) and (8).

[0092] Step S2022: determining the road slope based on the vehicle acceleration and the vehicle speed.

[0093] The road slope of the road the vehicle is currently on can be determined by the vehicle acceleration and speed.

[0094] Specifically, the step of determining the road slope based on the vehicle acceleration and the vehicle speed includes: determining the differential value of the vehicle speed; determining the Kalman filter state equation based on the differential value and a preset gravity acceleration; filtering the vehicle acceleration based on the Kalman filter equation to determine the road slope.

[0095] For the road slope, we can first determine the acceleration based on the differential value of the vehicle speed with respect to time, and then establish a Kalman filter state equation based on the differential value of the preset gravity acceleration to determine the filtering method for the acceleration. Then, we filter the vehicle acceleration based on the Kalman filter equation to determine the road slope.

[0096] For example, the kinematic method can be used to estimate the road slope:

[0097]

[0098] i=tanθ(10)

[0099] in is the reading of the acceleration sensor, v is the longitudinal velocity, g is the acceleration due to gravity, θ is the slope angle (uphill is positive), and i is the road slope.

[0100] Since the road slope is generally small, let θ = sinθ = tanθ

[0101]

[0102] Since there is noise in the acceleration sensor measurement value, and the noise follows Gaussian distribution, Kalman filtering is used to filter the acceleration measurement value and then calculate the road slope. The Kalman filtering algorithm includes the following five parts:

[0103] 1. Calculate the predicted value of state variables

[0104]

[0105] 2. Prediction covariance matrix

[0106]

[0107] 3. Calculate the filter gain matrix K k :

[0108]

[0109] 4. Update covariance

[0110]

[0111] 5. Calculate state estimates

[0112]

[0113] In the formula, is the system state transfer matrix; H is the system observation matrix; q k is the process noise covariance matrix; r k is the measurement noise covariance matrix. According to equations (12) to (16), the acceleration measured by the sensor is Filtering is performed to calculate the slope.

[0114] Step 203, determining a first correction coefficient based on the vehicle mass and / or the road slope;

[0115] Based on the change of the vehicle mass and / or the road slope, a corresponding correction coefficient is determined to determine the first correction coefficient.

[0116] Specifically, the step of determining the first correction coefficient based on the vehicle mass and / or the road slope includes: determining the calibrated mass and calibrated slope corresponding to the initial braking force; if the vehicle mass does not match the calibrated mass, determining the mass correction coefficient based on the vehicle mass and the calibrated mass; if the calibrated slope does not match the road slope, determining the slope correction coefficient based on the calibrated slope and the road slope; determining the mass correction coefficient and / or the slope correction coefficient as the first correction coefficient.

[0117] The calibration mass and calibration slope for the initial braking force calibration can be determined. The calibration mass and calibration slope can be obtained and stored in advance based on experiments. It can be determined whether the vehicle mass matches the calibration mass, that is, whether the vehicle mass is within the floating range of the calibrated calibration mass. If the vehicle mass exceeds the floating range of the calibrated calibration mass, it can be determined that the vehicle mass does not match the calibration mass, and the mass correction coefficient can be determined based on the ratio of the vehicle mass to the calibration mass. When the vehicle mass does not exceed the floating range of the calibrated calibration mass, no correction is required, and the mass correction coefficient can be empty. Correspondingly, it can also be determined whether the road slope matches the calibration slope, that is, whether the road slope is within the floating range of the calibrated calibration slope. If the road slope exceeds the floating range of the calibrated calibration slope, it can be determined that the road slope does not match the calibration slope, and the slope correction coefficient is determined based on the difference between the road slope and the calibration slope. When the road slope does not exceed the floating range of the calibrated slope, no correction is required and the slope correction coefficient can be empty. The slope correction coefficient and the mass correction coefficient are determined as the first correction coefficient.

[0118] For example, when the mass of the vehicle changes compared to the calibrated value, the mass correction factor k can be calculated. m , m is the current vehicle mass, and m0 is the vehicle mass during calibration. When the road slope changes, the slope correction coefficient can be calculated to keep the brake pedal feel constant: Where k is the deceleration generated by the unit wheel cylinder pressure or wheel side braking force when the slope is 0; g is the acceleration due to gravity, and θ is the difference between the road slope and the calibrated slope.

[0119] Step 204, obtaining the brake disc temperature;

[0120] Sensor data for temperature detection of the brake disc may be read from relevant sensors, and the brake disc temperature may be acquired based on the sensor data.

[0121] Step 205, determining a second correction coefficient based on the brake disc temperature;

[0122] The second correction coefficient can be determined based on the change in the brake disc temperature. The greater the change in the brake disc temperature, the greater the second correction coefficient. The second correction coefficient can be determined by using the brake disc friction coefficient corresponding to the brake disc temperature before the change and the brake disc temperature during calibration. For example, the friction coefficient corresponding to the temperature of the initial braking force calibration is μ0, and the friction coefficient corresponding to the current temperature is μ. The second correction coefficient determined based on the brake disc temperature

[0123] Step 206, using the first correction coefficient and / or the second correction coefficient to correct the initial braking force to determine a target braking force;

[0124] After the first correction coefficient and the second correction coefficient are determined, at least one of the first correction coefficient and the second correction coefficient may be used to correct the initial braking force to obtain the target braking force for control.

[0125] The step of using the first correction coefficient to correct the initial braking force and determining the target braking force includes: determining the target braking force by combining the first correction coefficient and the initial braking force.

[0126] That is, when the first correction coefficient is used for correction, the first correction coefficient and the initial braking force can be directly combined, and the target braking force can be determined by multiplying the two. For example, when the vehicle mass changes compared to the pedal feel calibration value, the first correction coefficient k can be determined. m , and calculate the deceleration generated by the unit wheel cylinder pressure as the system closed loop. In order to keep the vehicle braking force constant under the corresponding push rod stroke, the target wheel cylinder pressure p after the vehicle load changes m =k m p. m is the current vehicle mass, and m0 is the vehicle mass during calibration. When the road slope changes, in order to keep the brake pedal feel constant, the wheel cylinder pressure or wheel side braking force needs to be compensated accordingly. The target wheel cylinder pressure or braking force where p θ is the corrected rear wheel cylinder pressure or wheel side braking force under the corresponding push rod stroke, p is the wheel cylinder pressure or wheel side braking force under the corresponding push rod stroke when the slope is 0, and k is the deceleration generated by the unit wheel cylinder pressure or wheel side braking force when the slope is 0.

[0127] Correspondingly, when the second correction coefficient is used for correction, the second correction coefficient and the initial braking force can be directly combined, and the target braking force can be determined by multiplying the two. For example, when the temperature of the car brake disc changes, the current brake disc temperature T can be determined, corresponding to the friction coefficient μ; the brake disc temperature during calibration is T0, corresponding to the friction coefficient μ0. In order to keep the pedal feel constant and the braking force generated by the unit wheel cylinder pressure is the same, the second correction coefficient k is calculated. T , the target wheel cylinder pressure p after the vehicle brake disc temperature changes T =k T p. μ is the current disc friction coefficient, and μ0 is the disc friction coefficient during calibration.

[0128] In summary, continuing with the above example, when the vehicle mass, road slope and brake temperature are needed to correct the braking force, the corresponding formula can be:

[0129]

[0130] The target braking force can be determined by substituting the corresponding correction coefficient and initial braking force into the above formula (17). Correspondingly, based on different corrected target braking forces, the relationship between the push rod stroke and the brake pressure of the brake cylinder can be referred to Figure 3 , the target braking force is corrected based on different conditions. When the driver steps on the pedal to the same depth, the corresponding braking force can be determined to output the corresponding appropriate braking performance, avoiding insufficient or excessive braking, improving vehicle comfort and safety, and improving user experience.

[0131] Step 207: Perform braking control based on the target braking force.

[0132] Based on different wire control brake systems, the corresponding actuators are determined. For example, components such as electric hydraulic pumps and solenoid valves in the electronic hydraulic brake system (EHB), or electric motors in the electronic mechanical brake system (EMB) can all be actuators. The target braking force is output to the actuator, and the actuator adjusts the braking pressure or braking force in real time to achieve precise control of the braking force of each wheel.

[0133] The embodiment of the present application detects the vehicle's total vehicle mass, brake disc temperature and road slope. When external conditions such as the total vehicle mass, brake disc temperature and road slope change, a corresponding first correction coefficient or a second correction coefficient can be determined, and the initial braking force is corrected using at least one of the first correction coefficient and the second correction coefficient to meet the required target braking force. When the user presses the brake pedal as usual, the braking force can be dynamically adjusted in real time based on the changed total vehicle mass and road slope, so as to accurately output the braking efficiency and improve the comfort, safety and user experience of the vehicle.

[0134] In order to make the implementation process of the embodiment of the present application clear to those skilled in the art, an example is used for illustration below. This example can be applied to a system consisting of a brake-by-wire system and a constant pedal feel system. The brake-by-wire system has the function of dynamically adjusting the braking pressure or braking force. The brake-by-wire system brakes according to the target pressure or target braking force. The constant pedal feel system monitors the vehicle status and inputs the target pressure or target braking force into the brake-by-wire system. The constant pedal feel system can estimate the vehicle mass, slope, brake disc temperature, humidity and wear degree, etc., and correct the target pressure or target braking force according to the above parameters. That is, the constant pedal feel system can obtain vehicle status information in real time and calculate the target braking pressure or braking force and input it into the brake-by-wire system, which performs braking control. For details, please refer to Figure 4 , showing a step flow chart of an example of a braking control method for a wire control brake system of the present application.

[0135] When the driver steps on the brake pedal, braking control begins. The pedal feel constant module can monitor the road slope, brake disc temperature and load conditions to determine whether to adjust the target brake pressure or braking force. The load condition can be characterized by the vehicle mass.

[0136] When at least one of the road gradient, the brake disc temperature and the load condition changes, the compensated target pressure or braking force can be calculated. The brake-by-wire system builds pressure or performs braking control according to the target pressure.

[0137] When the road slope, brake disc temperature and load conditions do not change, the brake-by-wire system builds pressure or performs braking control according to the current target pressure.

[0138] The driver adjusts the pedal input according to the vehicle speed, deceleration, etc., and then repeats the above steps to continuously correct the target pressure or perform braking control until there is no input from the brake pedal, that is, the driver releases the brake pedal.

[0139] It should be noted that, for the method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present application are not limited by the described order of actions, because according to the embodiments of the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present application.

[0140] Reference Figure 5 , shows a structural block diagram of an embodiment of a brake control device for a wire-controlled brake system of the present application, and the brake control device for the wire-controlled brake system may specifically include the following modules:

[0141] A first acquisition module 501 is used to acquire vehicle state information when a braking request is received; the braking request has a corresponding initial braking force;

[0142] A first determination module 502, configured to determine the vehicle mass and the road slope based on the vehicle state information;

[0143] A second determination module 503, configured to determine a first correction coefficient based on the vehicle mass and / or the road slope;

[0144] A correction module 504, configured to correct the initial braking force using the first correction coefficient to determine a target braking force;

[0145] The control module 505 is used to perform braking control based on the target braking force.

[0146] In an optional embodiment of the present application, the vehicle state information includes vehicle acceleration, vehicle speed and output torque, and the first determination module 502 includes:

[0147] A vehicle mass determination submodule, configured to determine the vehicle mass based on the vehicle acceleration and the output torque;

[0148] The road gradient determination submodule is used to determine the road gradient based on the vehicle acceleration and the vehicle speed.

[0149] In an optional embodiment of the present application, the vehicle mass determination submodule includes:

[0150] a vehicle driving force determination unit, configured to determine the vehicle driving force according to the output torque;

[0151] A first establishing unit, used for establishing a first observation equation for the vehicle driving force and the vehicle acceleration;

[0152] The vehicle mass determination unit is used to solve the first observation equation based on the recursive least squares method to determine the vehicle mass.

[0153] In an optional embodiment of the present application, the road slope determination submodule includes:

[0154] A differential unit, used to determine a differential value of the vehicle speed;

[0155] A second establishing unit is used to determine a Kalman filter state equation according to the differential value and a preset gravity acceleration;

[0156] A road gradient determination unit is used to filter the vehicle acceleration based on the Kalman filter equation to determine the road gradient.

[0157] In an optional embodiment of the present application, the second determining module 503 includes:

[0158] A calibration determination submodule, used to determine a calibration mass and a calibration slope corresponding to the initial braking force;

[0159] a mass correction coefficient determination submodule, configured to determine a mass correction coefficient based on the whole vehicle mass and the calibrated mass in response to the whole vehicle mass not matching the calibrated mass;

[0160] a slope correction coefficient determination submodule, for determining a slope correction coefficient based on the calibrated slope and the road slope in response to the calibrated slope not matching the road slope;

[0161] The determination submodule is used to determine the slope correction coefficient and / or the slope correction coefficient as a first correction coefficient.

[0162] In an optional embodiment of the present application, the device further includes:

[0163] A second acquisition module is used to acquire the brake disc temperature;

[0164] a second correction coefficient determination module, configured to determine a second correction coefficient based on the brake disc temperature;

[0165] The third determination module is used to use the first correction coefficient and / or the second correction coefficient to correct the initial braking force and determine the target braking force.

[0166] In an optional embodiment of the present application, the correction module 504 includes:

[0167] The correction submodule is used to determine a target braking force by combining the first correction coefficient and the initial braking force.

[0168] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0169] Reference Figure 6 , the embodiment of the present application further provides a vehicle, comprising:

[0170] A processor 601 and a storage medium 602, wherein the storage medium 602 stores a computer program executable by the processor 601, and when the vehicle is running, the processor 601 executes the computer program to implement the braking control method of the wire control brake system as described in any one of the embodiments of the present application.

[0171] The memory may include a random access memory (RAM) or a non-volatile memory, such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the processor.

[0172] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0173] Reference Figure 7 The embodiment of the present application further provides a computer-readable storage medium 701, on which a computer program is stored. When the computer program is executed by a processor, the braking control method of the wire control brake system as described in any one of the embodiments of the present application is executed.

[0174] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0175] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, devices, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0176] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0177] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0178] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0179] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0180] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0181] The above is a detailed introduction to a braking control method of a wire control brake system, a braking control device of a wire control brake system, a vehicle and a computer-readable storage medium provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for a person skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A braking control method for a wire control brake system, characterized in that: include: Upon receiving a braking request, obtaining vehicle status information; The braking request has a corresponding initial braking force; Determine the vehicle mass and the road slope based on the vehicle state information; Determining a first correction coefficient based on the vehicle mass and / or the road slope; Correcting the initial braking force using the first correction coefficient to determine a target braking force; Braking control is performed based on the target braking force.

2. The method according to claim 1, characterized in that The vehicle state information includes vehicle acceleration, vehicle speed and output torque, and the step of determining the vehicle mass and road slope based on the vehicle state information includes: determining a vehicle mass based on the vehicle acceleration and the output torque; A road grade is determined based on the vehicle acceleration and the vehicle speed.

3. The method according to claim 2, characterized in that The step of determining the vehicle mass based on the vehicle acceleration and the output torque comprises: determining a vehicle driving force based on the output torque; Establishing a first observation equation for the vehicle driving force and the vehicle acceleration; The first observation equation is solved based on the recursive least square method to determine the vehicle mass.

4. The method according to claim 2, characterized in that: The step of determining the road gradient based on the vehicle acceleration and the vehicle speed comprises: determining a differential value of the vehicle speed; Determining a Kalman filter state equation according to the differential value and a preset gravity acceleration; The vehicle acceleration is filtered based on the Kalman filter equation to determine the road slope.

5. The method according to claim 2, characterized in that: The step of determining the first correction coefficient based on the vehicle mass and / or the road slope comprises: Determining a calibrated mass and a calibrated slope corresponding to the initial braking force; If the vehicle mass does not match the calibrated mass, determining a mass correction factor based on the vehicle mass and the calibrated mass; If the calibrated slope does not match the road slope, determining a slope correction factor based on the calibrated slope and the road slope; The mass correction coefficient and / or the slope correction coefficient are determined as the first correction coefficient.

6. The method according to claim 1, characterized in that The method further comprises: Get the brake disc temperature; determining a second correction factor based on the brake disc temperature; The first correction coefficient and / or the second correction coefficient are used to correct the initial braking force to determine the target braking force.

7. The method according to any one of claims 1 to 6, characterized in that: The step of using the first correction coefficient to correct the initial braking force and determine the target braking force includes: The target braking force is determined by combining the first correction coefficient and the initial braking force.

8. A brake control device for a wire control brake system, characterized in that: include: A first acquisition module, used for acquiring vehicle status information when a braking request is received; The braking request has a corresponding initial braking force; A first determination module, configured to determine a vehicle mass and a road slope based on the vehicle state information; A second determination module, configured to determine a first correction coefficient based on the vehicle mass and / or the road slope; A correction module, configured to correct the initial braking force using the first correction coefficient to determine a target braking force; A control module is used to perform braking control based on the target braking force.

9. A vehicle, characterized in that: The invention comprises a processor, a memory and a computer program stored in the memory and capable of running on the processor, wherein when the computer program is executed by the processor, the steps of the braking control method of the wire control brake system as claimed in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the brake control method of the wire control brake system according to any one of claims 1 to 7 are implemented.

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