Vehicle braking control method, device and equipment and storage medium

Abstract

The invention discloses a vehicle braking control method, device and equipment and a storage medium, and relates to the technical field of vehicle control, and the vehicle braking control method comprises the steps that the initial speed, the expected braking distance and the braking requirement during vehicle running are obtained; according to the initial speed, the expected braking distance and the braking requirement, a mapping relation table is inquired, target braking control parameters are determined, and the mapping relation table is constructed through a mapping relation between braking time and the braking distance constructed through a speed control curve; and braking control is conducted on the vehicle through the target braking control parameters. The specific adjusting parameters are determined according to the braking requirements, so that the target braking control parameters are determined according to the initial speed, the expected braking distance and the specific adjusting parameters, braking control is conducted on the vehicle according to the target braking control parameters, vehicle braking control can be conducted according to the user requirements, and the adjusting flexibility and applicability are improved.

Description

Technical Field

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

[0002] Current braking models all use preset braking parameters / curves, such as constant braking force, quadratic curve, proportional integral differential of speed, etc. The defect of these models is that they cannot take into account all the influencing factors in the braking process, and it is not easy for developers to adjust them. The adjustable control parameters cannot be directly related to the influencing factors in the braking process, resulting in the inability to flexibly control according to user needs. Summary of the invention

[0003] The main purpose of this application is to provide a vehicle braking control method, device, equipment and storage medium, aiming to solve the technical problem that braking control cannot be performed according to user needs.

[0004] To achieve the above objectives, the present application proposes a vehicle braking control method, the vehicle braking control method comprising:

[0005] Obtain the initial speed, expected braking distance and braking demand of the vehicle;

[0006] According to the initial speed, the expected braking distance and the braking demand, a mapping relationship table is queried to determine a target braking control parameter, wherein the mapping relationship table is constructed by a mapping relationship between braking time and braking distance constructed by a speed control curve;

[0007] The vehicle is braked and controlled using the target braking control parameter.

[0008] In one embodiment, the step of querying a mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine the target braking control parameter comprises:

[0009] determining a target influencing factor according to the braking demand;

[0010] According to the initial speed, the expected braking distance and the target influencing factor, a mapping relationship table is searched to obtain a target speed control curve corresponding to the expected braking distance;

[0011] The target braking control parameter is determined by the target speed control curve.

[0012] In one embodiment, the construction of the mapping relationship table includes:

[0013] Setting an expected braking time, and constructing a speed optimization model with time as a variable based on the expected braking time;

[0014] Determine an optimization target based on the speed optimization model, and establish a comprehensive cost function through the optimization target;

[0015] Solving the comprehensive cost function to obtain a plurality of discrete speed change rate values;

[0016] Fitting a plurality of discrete speed change rate values ​​to obtain a plurality of reference speed control curves;

[0017] A plurality of actual braking distances are calculated based on the plurality of reference speed control curves, and a mapping relationship between braking time and braking distance is constructed through the plurality of actual braking distances to obtain a mapping relationship table.

[0018] In one embodiment, the step of calculating a plurality of actual braking distances based on the plurality of reference speed control curves, and constructing a mapping relationship between braking time and braking distance through the plurality of actual braking distances to obtain a mapping relationship table comprises:

[0019] Integrating and derivatizing a plurality of the reference speed control curves to calculate a plurality of actual braking distances;

[0020] Determining required braking time data required for the vehicle to stop completely from starting braking according to the plurality of reference speed control curves;

[0021] Acquire the corresponding initial speeds under the plurality of the actual braking distances and the required braking time data;

[0022] A mapping relationship between braking time and braking distance is established according to the corresponding initial speed, the plurality of actual braking distances and the required braking time data to obtain a mapping relationship table.

[0023] In one embodiment, the step of solving the comprehensive cost function to obtain a plurality of discrete speed change rate values ​​comprises:

[0024] Initialize one or more starting points of the speed change rate;

[0025] Calculate the comprehensive cost function value and gradient under the current speed change rate value;

[0026] adjusting the current speed change rate value according to the gradient to reduce the comprehensive cost function value;

[0027] When the cost change is less than the set threshold, the adjustment of the current speed change rate value is stopped, and the current speed change rate value at each adjustment is obtained to obtain multiple discrete speed change rate values.

[0028] In one embodiment, the step of fitting the plurality of discrete speed change rate values ​​to obtain a plurality of reference speed control curves comprises:

[0029] Fitting a plurality of discrete speed change rate values ​​to obtain a plurality of initial speed curves;

[0030] Get the influence weights of braking start and braking stop;

[0031] The multiple initial speed curves are adjusted according to the influence weights to obtain multiple reference speed control curves.

[0032] In one embodiment, the step of determining an optimization target based on the speed optimization model and establishing a comprehensive cost function through the optimization target includes:

[0033] Obtaining a plurality of influencing factors based on the speed optimization model;

[0034] Taking the multiple influencing factors as multiple optimization targets;

[0035] constructing a cost function that associates a plurality of said optimization objectives;

[0036] Assigning a corresponding weight coefficient to each of the cost functions;

[0037] A comprehensive cost function is established by using the weight coefficients and the cost function.

[0038] In addition, to achieve the above-mentioned purpose, the present application also proposes a vehicle brake control device, the vehicle brake control device comprising:

[0039] An acquisition module is used to acquire the initial speed, expected braking distance and braking demand of the vehicle when it is traveling;

[0040] A query module, configured to query a mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine a target braking control parameter, wherein the mapping relationship table is constructed by a mapping relationship between braking time and braking distance constructed by a speed control curve;

[0041] A control module is used to perform braking control on the vehicle through the target braking control parameter.

[0042] In addition, to achieve the above-mentioned purpose, the present application also proposes a vehicle braking control device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the computer program is configured to implement the steps of the vehicle braking control method described above.

[0043] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the vehicle braking control method described above are implemented.

[0044] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the vehicle braking control method described above are implemented.

[0045] One or more technical solutions proposed in this application obtain the initial speed, expected braking distance and braking demand of the vehicle when it is traveling; query the mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine the target braking control parameters, wherein the mapping relationship table is constructed by the mapping relationship between the braking time and the braking distance constructed by the speed control curve; and brake the vehicle through the target braking control parameters. Determine the specific adjustment parameters through the braking demand, thereby determining the target braking control parameters through the initial speed, the expected braking distance and the specific adjustment parameters, and brake the vehicle through the target braking control parameters. The vehicle braking control can be performed according to user needs, thereby improving the flexibility and applicability of the adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] 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 present application.

[0047] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0048] Figure 1 A schematic diagram of a flow chart provided for the first embodiment of the vehicle braking control method of the present application;

[0049] Figure 2 A schematic diagram of a flow chart provided for the second embodiment of the vehicle braking control method of the present application;

[0050] Figure 3 A schematic diagram of a flow chart provided for the third embodiment of the vehicle braking control method of the present application;

[0051] Figure 4 This is a schematic diagram of the process of speed changing over time from braking to stopping at the current speed in one embodiment of the vehicle braking control method of the present application;

[0052] Figure 5 This is a schematic diagram of a speed curve segment in an embodiment of the vehicle braking control method of the present application;

[0053] Figure 6 A schematic diagram of a simplified process of a vehicle braking control method provided in Embodiment 2 of the present application;

[0054] Figure 7 This is a schematic diagram of the module structure of the vehicle brake control device according to an embodiment of the present application;

[0055] Figure 8 Schematic diagram of the device structure of the hardware operating environment involved in the vehicle braking control method in the embodiment of the present application.

[0056] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0057] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0058] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0059] The main solution of the embodiment of the present application is: obtaining the initial speed, expected braking distance and braking demand of the vehicle during driving; querying the mapping relationship table according to the initial speed, the expected braking distance and the braking demand, and determining the target braking control parameters, wherein the mapping relationship table is constructed by the mapping relationship between the braking time and the braking distance constructed by the speed control curve; and braking control of the vehicle is performed through the target braking control parameters.

[0060] Since the existing technologies all adopt preset braking parameters / curves for vehicle braking control, such as constant braking force, quadratic curve, PID (proportional-integral-differential) for speed, etc., the factors that need to be considered during the braking process include: ① braking distance, which affects braking safety and accuracy; ② acceleration and pitch angle in the X direction during braking, which affect braking smoothness and comfort; ③ sudden change in acceleration at the beginning of braking, which affects the braking impact; ④ sudden change in acceleration and pitch angle at the end of braking, which affects comfort. The defects of these models are that they cannot take into account all the above-mentioned influencing factors; and it is not easy for developers to adjust them. The adjustable control parameters cannot be directly associated with the above-mentioned influencing factors, resulting in the inability to flexibly control the vehicle's braking.

[0061] The present application provides a solution to display and adjust the braking distance, X-axis acceleration during braking, acceleration mutation at the beginning of braking, acceleration mutation at the end of braking, and Pitch angle according to actual needs, thereby improving the flexibility and applicability of the adjustment and improving the comfort of vehicle braking control.

[0062] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, a vehicle brake control device, etc. The following takes the controller in the vehicle brake control device as an example to illustrate this embodiment and the following embodiments.

[0063] Based on this, the embodiment of the present application provides a vehicle braking control method, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the vehicle braking control method of the present application.

[0064] In this embodiment, the vehicle braking control method includes steps S10 to S30:

[0065] Step S10: Obtaining the initial speed, expected braking distance and braking demand of the vehicle.

[0066] It should be noted that the initial speed of the vehicle when it is traveling is the speed when the vehicle starts to brake, which can be acquired by a speed sensor.

[0067] The expected braking distance is the distance that the driver or the system wants the vehicle to slow down from the current speed to a complete stop. When the vehicle needs to be braked, the expected braking distance input by the user can be received, such as 2m, 3m, etc., which is not limited in this embodiment. The braking demand is the braking influencing factor that the user is concerned about, such as the acceleration during the braking process, the acceleration mutation at the beginning of braking, the acceleration mutation at the end of braking, and the pitch angle, etc., which may also include other influencing factors, which are not limited in this embodiment.

[0068] Step S20: querying a mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine a target braking control parameter, wherein the mapping relationship table is constructed by a mapping relationship between braking time and braking distance constructed through a speed control curve.

[0069] It can be understood that the mapping relationship table represents the mapping relationship between braking time and braking distance, and each influencing factor is related to time. Therefore, the mapping relationship table can be queried based on the current initial speed, expected braking distance and braking demand to obtain the corresponding braking time and the corresponding speed control curve.

[0070] The speed control curve is obtained by solving and fitting the established Vt optimization model with different weights of different influencing factors. Under different initial speeds and different braking requirements, the corresponding speed control curves are different. The mapping relationship between braking time and braking distance can be established based on the speed control curve, thereby constructing a mapping relationship table.

[0071] It should be noted that the target braking control parameters may include target deceleration, braking force, etc., and may also include other braking parameters.

[0072] Step S30: performing braking control on the vehicle using the target braking control parameter.

[0073] In a specific implementation, after determining the target braking control parameters corresponding to the current initial speed, expected braking distance and braking demand, the vehicle can be braked using the target braking control parameters to ensure the safety, smoothness and comfort of the vehicle during braking.

[0074] This embodiment provides a vehicle braking control method, which obtains the initial speed, expected braking distance and braking demand of the vehicle when it is traveling; queries a mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine a target braking control parameter, wherein the mapping relationship table is constructed by a mapping relationship between braking time and braking distance constructed by a speed control curve; and brakes the vehicle using the target braking control parameter. Determine specific adjustment parameters based on braking demand, thereby determining target braking control parameters based on initial speed, expected braking distance and specific adjustment parameters, and brake control the vehicle using the target braking control parameters. Vehicle braking control can be performed according to user needs, thereby improving the flexibility and applicability of adjustment.

[0075] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 2 , step S20 includes steps S201 to S203:

[0076] Step S201: determining a target influencing factor according to the braking demand.

[0077] It should be noted that the braking demand may include braking demands at different times or positions. When the braking demand is different, the corresponding influencing factors are different. For example, if the braking demand is the smoothness requirement at the start of braking, the target influencing factors include the smoothness factor at the start of braking. For example, if the braking demand is the smoothness and comfort during the braking process, the target influencing factors include: X-axis acceleration consistency factor and pitch frequency smoothness factor.

[0078] Step S202: querying a mapping relationship table according to the initial speed, the expected braking distance and the target influencing factor to obtain a reference speed control curve corresponding to the expected braking distance.

[0079] In a specific implementation, a mapping relationship table can be queried according to the initial speed, expected braking distance and target influencing factor. The mapping relationship table includes speed control curves corresponding to different initial speeds, different expected braking distances and different influencing factors. Specifically, the corresponding expected control time can be determined through the initial speed and the expected braking distance, and the reference speed control curve corresponding to the expected braking distance can be determined through the expected control time, the initial speed and the target influencing factor.

[0080] Step S203: Determine target braking control parameters through the target speed control curve.

[0081] In a specific implementation, the target speed control curve can be analyzed to derive the change of acceleration (or deceleration) over time. After the deceleration is obtained, the braking force required for vehicle braking can be calculated, so that parameters such as deceleration and braking force can be used as target braking control parameters.

[0082] Determine the influencing factor according to the braking demand; query the mapping relationship table according to the initial speed and the expected braking distance to obtain the target braking time and the actual braking distance; calculate the target braking control parameter according to the target braking time, the actual braking distance and the influencing factor. The target braking control parameter is obtained through the pre-constructed mapping relationship table, and is directly used for the braking control of the vehicle, ensuring that the braking process meets the safety requirements and provides a good driving experience.

[0083] Based on the first embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 3 Before step S20, the construction of the mapping relationship table includes steps S11 to S15:

[0084] Step S11: setting an expected braking time, and constructing a speed optimization model with time as a variable based on the expected braking time.

[0085] It should be noted that since all influencing factors are related to time, a Vt optimization model can be established in the time domain, that is, a speed optimization model with time as a variable, and the expected braking time can be set in advance, so as to draw a speed change curve when the car brakes, such as Figure 4 As shown, Figure 4 This is a schematic diagram of the process of speed changing from braking at the current speed to stopping over time, such as Figure 5 As shown, Figure 5It is a schematic diagram of the speed curve segmentation. When taking an infinitely small time period t, the speed change can be approximated into a straight line, V is the initial speed, ΔV is the speed change within time 2t, and V1 is the speed change per unit time. The speed optimization model represents the change of speed over time during the braking process.

[0086] Step S12: determining an optimization target based on the speed optimization model, and establishing a comprehensive cost function through the optimization target.

[0087] In a specific implementation, a specific optimization target can be set based on the constructed speed optimization model, so as to establish a comprehensive cost function through the optimization target, and the comprehensive cost function is represented by cost.

[0088] The speed optimization model usually involves defining a series of influencing factors, such as the consistency of X-axis acceleration and the smoothness of pitch frequency, and constructing a cost function by combining these factors to construct a comprehensive cost function.

[0089] In a feasible implementation, step S12 may include steps A11 to A15:

[0090] Step A11: obtaining a plurality of influencing factors based on the speed optimization model;

[0091] Step A12: taking the multiple influencing factors as multiple optimization targets;

[0092] It should be noted that, by analyzing the speed optimization model, multiple influencing factors can be obtained, and the multiple influencing factors can be used as multiple optimization targets. For example, the influencing factors include the x-axis acceleration consistency factor, the pitch frequency smoothness factor, the braking distance attention factor, the braking start and braking stop smoothness factor, etc. Multiple optimization targets can be obtained through the above influencing factors.

[0093] Step A13: constructing a cost function associated with a plurality of the optimization objectives;

[0094] In a specific implementation, a cost function associated with multiple optimization objectives may be constructed, including cost1, cost2, cost3, and cost4, where cost1 is the x-axis acceleration and cost1 is expressed as follows:

[0095] cost1=y1=∫(a)^2=∫[(V1 / t)^2+((ΔV-V1) / t)^2]

[0096] dy1 / dV1=(2V1-ΔV) / t^2

[0097] In the above formula, V1 is the initial velocity, ΔV is the velocity change within the time 2t, and V1 is the velocity change per unit time.

[0098] cost2 is the Pitch Rate, expressed as follows:

[0099] cost2=y2=∫(a')^2=∫[(V1 / t-(ΔV-V1) / t) / t]^2

[0100] dy2 / dV1=(8V1-4ΔV) / t^4

[0101] cost3 is the braking distance, expressed as follows:

[0102] cost3=y3=∫V dt=∫[(V+V-V1) / 2+(V-V1+V-ΔV) / 2]dt;

[0103] dy3 / dV1=-1

[0104] Cost4 is the acceleration mutation when braking starts and when braking stops. It is expressed as follows:

[0105] cost4=J=K1*[y'(0)-a0]^2+K2*[y'(tend)-0]^2

[0106] Where y'(0) is the acceleration at the beginning of braking, a0 is the acceleration of the vehicle at the beginning of braking, y'(tend) is the acceleration at the moment of braking to stop, and K1 and K2 are adjusted to minimize J.

[0107] Step A14: assigning corresponding weight coefficients to each of the cost functions;

[0108] In the specific implementation, the user's subjective feelings can be adjusted by setting weights to achieve multi-objective optimization. Therefore, the corresponding weight coefficient can be assigned to each cost function. The weight coefficient w1: braking pitch frequency smoothness coefficient, w2: braking distance attention coefficient, k1: braking initial state consistency coefficient, k2: braking stop smoothness coefficient.

[0109] Step A15: Establish a comprehensive cost function using the weight coefficient and the cost function.

[0110] In a specific implementation, a comprehensive cost function can be established through weight coefficients and cost functions, and the comprehensive cost function cost = Cost1 + w1*Cost2 + w2*Cost3 = y1 + w1*y2 + w2*y3, where w1 and w2 are weighting coefficients. y1 is the cost related to the consistency of the X-axis acceleration, w1 and w2 are the cost weights of the pitch frequency smoothness and the braking distance concern respectively; y2 and y3 are the cost expressions of these two factors respectively.

[0111] Step S13: Solving the comprehensive cost function to obtain a plurality of discrete speed change rate values.

[0112] It should be understood that a series of discrete solutions can be obtained by solving the comprehensive cost function, thereby obtaining a plurality of discrete speed change rate values.

[0113] For nonlinear optimization problems, a variety of algorithms can be selected to find the V1 value that minimizes the comprehensive cost function. Common numerical optimization methods include: gradient descent, genetic algorithm, particle swarm optimization, etc.

[0114] In a feasible implementation, step S13 may include steps B11 to B14:

[0115] Step B11: Initialize one or more starting points of the speed change rate;

[0116] It should be noted that the comprehensive cost function can be solved by using the gradient descent method. By calculating the derivative of the cost function with respect to V1, the V1 value is iteratively updated along the derivative direction. Therefore, one or more starting points of the initial velocity change rate V1 can be initialized first.

[0117] Step B12: Calculate the comprehensive cost function value and gradient under the current speed change rate value;

[0118] By calculating the comprehensive cost function value and gradient under the current V1 value, that is, the partial derivative of the cost function with respect to V1.

[0119] Step B13: adjusting the current speed change rate value according to the gradient to reduce the comprehensive cost function value;

[0120] In a specific implementation, the current speed change rate value V1 can be adjusted according to the gradient information to move in the direction of reducing the cost, thereby reducing the comprehensive cost function value.

[0121] Step B14: When the cost change is less than the set threshold, stop adjusting the current speed change rate value, and obtain the current speed change rate value at each adjustment to obtain multiple discrete speed change rate values.

[0122] It should be noted that iteration limits can be set, for example, a set threshold for cost change can be set. When the cost change is less than the set threshold, the adjustment of the current speed change rate value can be stopped. The maximum number of iterations can also be set. When the adjustment number reaches the maximum number of iterations, the adjustment of the current speed change rate value can be stopped.

[0123] By adjusting the speed change rate value, a series of V1 values ​​that minimize the cost function are found to obtain multiple discrete speed change rate values.

[0124] Step S14: fitting the plurality of discrete speed change rate values ​​to obtain a plurality of reference speed control curves.

[0125] In a specific implementation, multiple discrete speed change rate values ​​may be fitted to obtain a smooth speed control curve, that is, multiple reference speed control curves.

[0126] Specifically, let dCost / dV1=dy1 / dV1+w1*dy2 / dV1+w2*dy3 / dV1=0, and the expression of the speed curve is as follows:

[0127] y=V1=(w2*t^4+4w1*ΔV+t^2*ΔV) / (2*t^2+8w1)

[0128] Wherein, ΔV is a linear function of t, and when different weight coefficients are input, the corresponding speed curve is different.

[0129] In a feasible implementation, step S14 may include steps C11 to C13:

[0130] Step C11: fitting the plurality of discrete speed change rate values ​​to obtain a plurality of initial speed curves;

[0131] It should be noted that the initial speed curve expression with the coefficient expressed by w2 can be obtained by first fitting the discrete speed change rate values, that is, y=V1=(w2*t^4+4w1*ΔV+t^2*ΔV) / (2*t^2+8w1).

[0132] Step C12: Obtaining the influence weights of braking start and braking stop;

[0133] In a specific implementation, on this basis, the influence weights of adjusting the braking start and braking stop, namely k1 and k2, can be added.

[0134] Step C13: adjusting the multiple initial speed curves according to the influence weights to obtain multiple reference speed control curves.

[0135] It should be understood that the expression corresponding to the initial speed curve can be adjusted according to the influence weight to obtain multiple reference speed control curves. Specifically, the initial speed curve expression can be adjusted according to the influence weight to obtain the expression of the reference speed control curve, thereby constructing multiple reference speed control curves.

[0136] Specifically, the initial speed V=80km / h at the beginning of braking, the expected braking time t=3.9s, the weight coefficients w1=0, w2=5, so that the program can generate discrete speed V1-t pairs, and perform linear fitting on the discrete data to obtain a smooth speed control curve y=V1=1.25x2-25.39x+80. For example, input V = 80km / h, t = 6.9s, w1 = 0, w2 = 0.5, and get the speed control curve: y = 0.125x2 -12.46x + 80; input: V = 80km / h, t = 3.9s, w1 = 0, w2 = 20, and get the speed control curve: y = 5x2 -40.01x + 80; input: V = 100km / h, t = 6.9s, w1 = 0, w2 = 0.5, and get the speed control curve: y = 0.125x2-15.72x + 100; input: V = 100km / h, t = 9.2s, w1 = 0, w2 = 0.5, and get the speed control curve: y = 0.125x2 -12.02x+100; input: V=100km / h, t=9.2s, w1=1, w2=5, and get the speed control curve: y=1.059x2 -20.61x+100.

[0137] Step S15: Calculate a plurality of actual braking distances based on the plurality of reference speed control curves, and construct a mapping relationship between braking time and braking distance through the plurality of actual braking distances to obtain a mapping relationship table.

[0138] In a specific implementation, a plurality of actual braking distances S under the reference speed curve are calculated according to different reference speed control curves, so that a mapping relationship between braking time and braking distance is constructed according to the plurality of actual braking distances to obtain a mapping relationship table.

[0139] The speed optimization model in the time domain can be restored to the parameter space of the vehicle's current speed, current acceleration and actual braking distance, thereby suggesting a mapping between the expected braking time and the expected braking distance, and generating a map table, which facilitates direct input of the initial speed and expected braking distance according to the mapping relationship table to complete the actual vehicle control.

[0140] In a feasible implementation, step S15 may include steps D11 to D14:

[0141] Step D11: Integrate and derive the plurality of reference speed control curves to calculate the actual braking distance.

[0142] In a specific implementation, for each reference speed control curve v(t), the actual braking distance can be calculated by integration, as shown below:

[0143]

[0144] Among them, t end is the time it takes for the vehicle to come to a complete stop.

[0145] Step D12: Determine the required braking time required for the vehicle to stop completely from the start of braking according to the plurality of reference speed control curves.

[0146] Similarly, the braking time t required for the vehicle to stop completely from starting braking can be determined based on multiple reference speed control curves. brake .

[0147] Step D13: Obtaining the actual braking distance and the corresponding initial speed under the required braking time.

[0148] In a specific implementation, multiple initial speed values ​​V and corresponding expected braking distances S can be selected. desired .

[0149] Step D14: establishing a mapping relationship between braking time and braking distance according to the corresponding initial speed, the actual braking distance and the required braking time, and obtaining a mapping relationship table.

[0150] For each selected initial speed and expected braking distance combination, the corresponding actual braking distance and required braking time are obtained. For each initial speed V, a set of data points (S desired , t brake ), thereby constructing a mapping relationship between braking time and braking distance and obtaining a mapping relationship table.

[0151] When a braking operation is required, the mapping table can be quickly queried according to the initial speed of the vehicle and the expected braking distance set by the driver to obtain the corresponding braking time and other braking control parameters.

[0152] As shown in Table 1, Table 1 is a mapping relationship table. For example, if the expected braking distance is 50m and the initial speed is 80km / h, the corresponding braking time is 3.9s. The corresponding target speed control curve can be determined to obtain the target braking control parameters, and the vehicle is braked by the target braking control parameters.

[0153] Table 1

[0154] Initial speed (km / h) Expected braking distance (m) Actual braking distance (m) Braking time(s) 80 50 50 3.9 80 60 60 4.5 80 70 70 5.2 100 50 50 3.2 100 60 60 3.8 100 70 70 4.4

[0155] This embodiment sets the expected braking time, and constructs a speed optimization model with time as a variable based on the expected braking time; determines the optimization target based on the speed optimization model, and establishes a comprehensive cost function through the optimization target; solves the comprehensive cost function to obtain multiple discrete speed change rate values; fits multiple discrete speed change rate values ​​to obtain multiple target speed control curves; calculates the actual braking distance based on multiple target speed control curves, and constructs a mapping relationship between braking time and braking distance through the actual braking distance to obtain a mapping relationship table. In the actual driving process, the corresponding braking time and control parameters can be quickly found according to the current speed of the vehicle and the expected braking distance using the pre-constructed mapping relationship table. Compared with the real-time calculation of complex speed control curves, the response speed and processing efficiency of the system are greatly improved.

[0156] For example, in order to help understand the implementation process of the vehicle braking control method obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 6 , Figure 6 A brief flow chart of a vehicle braking control method is provided, specifically: by constructing an optimization function, i.e., a speed optimization model, selecting an optimization target, adjusting the optimization target weight to obtain a discrete result, fitting the discrete result, generating a speed control curve, restoring the parameters corresponding to the speed control curve to a speed, acceleration, and braking distance parameter space, thereby establishing a mapping between braking time and braking distance, and completing real vehicle control by looking up a table according to the input parameters of the current control, so that the braking distance, the X-axis acceleration during braking, the acceleration mutation at the beginning of braking, the acceleration mutation at the end of braking, and the pitch angle can be displayed and adjusted according to the actual needs of the user.

[0157] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the vehicle braking control method of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0158] This application also provides a vehicle brake control device, please refer to Figure 7 , the vehicle brake control device comprises:

[0159] The acquisition module 10 is used to acquire the initial speed, expected braking distance and braking demand of the vehicle when it is traveling.

[0160] The query module 20 is used to query the mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine the target braking control parameter, wherein the mapping relationship table is constructed by the mapping relationship between the braking time and the braking distance constructed by the speed control curve.

[0161] The control module 30 is used to perform braking control on the vehicle through the target braking control parameter.

[0162] The vehicle braking control device provided by the present application adopts the vehicle braking control method in the above embodiment, which can solve the technical problem that braking control cannot be performed according to user needs. Compared with the prior art, the beneficial effects of the vehicle braking control device provided by the present application are the same as the beneficial effects of the vehicle braking control method provided by the above embodiment, and other technical features in the vehicle braking control device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0163] In one embodiment, the query module 20 is also used to determine the influencing factor according to the braking demand; query the mapping relationship table according to the initial speed and the expected braking distance to obtain the target braking time and the actual braking distance; calculate the target braking control parameter through the target braking time, the actual braking distance and the influencing factor.

[0164] In one embodiment, the device also includes a construction module, which is used to set an expected braking time and construct a speed optimization model with time as a variable based on the expected braking time; determine an optimization target based on the speed optimization model, and establish a comprehensive cost function through the optimization target; solve the comprehensive cost function to obtain multiple discrete speed change rate values; fit the multiple discrete speed change rate values ​​to obtain multiple target speed control curves; calculate the actual braking distance based on the multiple target speed control curves, and construct a mapping relationship between braking time and braking distance through the actual braking distance to obtain a mapping relationship table.

[0165] In one embodiment, the construction module is further used to integrate and differentiate the multiple target speed control curves to calculate the actual braking distance; determine the required braking time required for the vehicle to stop completely from the start of braking based on the multiple target speed control curves; obtain the actual braking distance and the corresponding initial speed under the required braking time; establish a mapping relationship between braking time and braking distance based on the corresponding initial speed, the actual braking distance and the required braking time, and obtain a mapping relationship table.

[0166] In one embodiment, the construction module is also used to initialize one or more starting points of the speed change rate; calculate the comprehensive cost function value and gradient under the current speed change rate value; adjust the current speed change rate value according to the gradient to reduce the comprehensive cost function value; when the cost change is less than the set threshold, stop adjusting the current speed change rate value, and obtain the current speed change rate value at each adjustment to obtain multiple discrete speed change rate values.

[0167] In one embodiment, the construction module is also used to fit multiple discrete speed change rate values ​​to obtain multiple initial speed curves; obtain the influence weights when braking starts and when braking stops; and adjust the multiple initial speed curves according to the influence weights to obtain multiple target speed control curves.

[0168] In one embodiment, the construction module is also used to obtain multiple influencing factors based on the speed optimization model; use the multiple influencing factors as multiple optimization targets; construct a cost function that associates the multiple optimization targets; assign a corresponding weight coefficient to each cost function; and establish a comprehensive cost function through the weight coefficient and the cost function.

[0169] The present application provides a vehicle braking control device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the vehicle braking control method in the above-mentioned embodiment one.

[0170] Reference below Figure 8 , which shows a schematic diagram of the structure of a vehicle brake control device suitable for implementing an embodiment of the present application. The vehicle brake control device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 8 The vehicle brake control device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0171] like Figure 8As shown, the vehicle brake control device may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a ROM (Read Only Memory) 1002 or a program loaded from a storage device 1003 to a RAM (Random Access Memory) 1004. In the RAM 1004, various programs and data required for the operation of the vehicle brake control device are also stored. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, an LCD (Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the vehicle brake control device to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows a vehicle brake control device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or provided instead.

[0172] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0173] The vehicle braking control device provided by the present application adopts the vehicle braking control method in the above embodiment, which can solve the technical problem that braking control cannot be performed according to user needs. Compared with the prior art, the beneficial effects of the vehicle braking control device provided by the present application are the same as the beneficial effects of the vehicle braking control method provided by the above embodiment, and other technical features in the vehicle braking control device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0174] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0175] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0176] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, wherein the computer-readable program instructions are used to execute the vehicle braking control method in the above-mentioned embodiment.

[0177] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, RAM (Random Access Memory), ROM (Read Only Memory), EPROM (Erasable Programmable Read Only Memory, Erasable Programmable Read Only Memory or Flash Memory), optical fiber, CD-ROM (CD-Read Only Memory, portable compact disk read-only memory), optical storage device, magnetic storage device, or any suitable combination of the above. In the present embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0178] The computer-readable storage medium may be included in the vehicle brake control device; or may exist independently without being assembled into the vehicle brake control device.

[0179] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the vehicle braking control device, the vehicle braking control device: obtains the initial speed, expected braking distance and braking demand of the vehicle during driving; queries a mapping relationship table according to the initial speed, the expected braking distance and the braking demand, and determines the target braking control parameters, wherein the mapping relationship table is constructed by the mapping relationship between the braking time and the braking distance constructed by the speed control curve; and performs braking control on the vehicle through the target braking control parameters.

[0180] The computer program code for performing the operation of the present application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, and conventional procedural programming languages, such as "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on the remote computer, or completely on the remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network, including a LAN (Local Area Network) or a WAN (Wide Area Network), or it can be connected to an external computer (e.g., using an Internet service provider to connect through the Internet).

[0181] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0182] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0183] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned vehicle braking control method, and can solve the technical problem that braking control cannot be performed according to user needs. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the vehicle braking control method provided by the above-mentioned embodiment, and will not be repeated here.

[0184] The present application also provides a computer program product, comprising a computer program, which implements the steps of the vehicle braking control method as described above when executed by a processor.

[0185] The computer program product provided by the present application can solve the technical problem that the braking control cannot be performed according to the user's needs. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the vehicle braking control method provided by the above embodiment, which will not be repeated here.

[0186] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A vehicle braking control method, characterized in that: The vehicle braking control method comprises: Obtain the initial speed, expected braking distance and braking demand of the vehicle; According to the initial speed, the expected braking distance and the braking demand, a mapping relationship table is queried to determine a target braking control parameter, wherein the mapping relationship table is constructed by a mapping relationship between braking time and braking distance constructed by a speed control curve; The vehicle is braked and controlled using the target braking control parameter.

2. The method according to claim 1, characterized in that The step of querying a mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine the target braking control parameter comprises: determining a target influencing factor according to the braking demand; According to the initial speed, the expected braking distance and the target influencing factor, a mapping relationship table is searched to obtain a target speed control curve corresponding to the expected braking distance; The target braking control parameter is determined by the target speed control curve.

3. The method according to claim 1, characterized in that The construction of the mapping relationship table includes: Setting an expected braking time, and constructing a speed optimization model with time as a variable based on the expected braking time; Determine an optimization target based on the speed optimization model, and establish a comprehensive cost function through the optimization target; Solving the comprehensive cost function to obtain a plurality of discrete speed change rate values; Fitting a plurality of discrete speed change rate values ​​to obtain a plurality of reference speed control curves; A plurality of actual braking distances are calculated based on the plurality of reference speed control curves, and a mapping relationship between braking time and braking distance is constructed through the plurality of actual braking distances to obtain a mapping relationship table.

4. The method according to claim 3, characterized in that The step of calculating a plurality of actual braking distances based on the plurality of reference speed control curves, and constructing a mapping relationship between braking time and braking distance through the plurality of actual braking distances to obtain a mapping relationship table comprises: Integrating and derivatizing a plurality of the reference speed control curves to calculate a plurality of actual braking distances; Determining required braking time data required for the vehicle to stop completely from starting braking according to the plurality of reference speed control curves; Acquire the corresponding initial speeds under the plurality of the actual braking distances and the required braking time data; A mapping relationship between braking time and braking distance is established according to the corresponding initial speed, the plurality of actual braking distances and the required braking time data to obtain a mapping relationship table.

5. The method according to claim 3, characterized in that The step of solving the comprehensive cost function to obtain a plurality of discrete speed change rate values ​​comprises: Initialize one or more starting points of the speed change rate; Calculate the comprehensive cost function value and gradient under the current speed change rate value; adjusting the current speed change rate value according to the gradient to reduce the comprehensive cost function value; When the cost change is less than the set threshold, the adjustment of the current speed change rate value is stopped, and the current speed change rate value at each adjustment is obtained to obtain multiple discrete speed change rate values.

6. The method according to claim 3, characterized in that The step of fitting the plurality of discrete speed change rate values ​​to obtain a plurality of reference speed control curves comprises: Fitting a plurality of discrete speed change rate values ​​to obtain a plurality of initial speed curves; Get the influence weights of braking start and braking stop; The multiple initial speed curves are adjusted according to the influence weights to obtain multiple reference speed control curves.

7. The method according to any one of claims 3 to 6, characterized in that The step of determining the optimization target based on the speed optimization model and establishing the comprehensive cost function through the optimization target comprises: Obtaining a plurality of influencing factors based on the speed optimization model; Taking the multiple influencing factors as multiple optimization targets; constructing a cost function that associates a plurality of said optimization objectives; Assigning a corresponding weight coefficient to each of the cost functions; A comprehensive cost function is established by using the weight coefficients and the cost function.

8. A vehicle brake control device, characterized in that: The device comprises: An acquisition module is used to acquire the initial speed, expected braking distance and braking demand of the vehicle when it is traveling; A query module, configured to query a mapping relationship table according to the initial speed, the expected braking distance and the braking demand to determine a target braking control parameter, wherein the mapping relationship table is constructed by a mapping relationship between braking time and braking distance constructed by a speed control curve; A control module is used to perform braking control on the vehicle through the target braking control parameter.

9. A vehicle brake control device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the vehicle braking control method according to any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the vehicle braking control method according to any one of claims 1 to 7 are implemented.

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