Vehicle braking method, device and equipment, storage medium and computer program product

Abstract

The invention discloses a vehicle braking method, device and equipment, a storage medium and a computer program product, and relates to the technical field of vehicles. The method comprises the steps that under the condition that a first vehicle triggers a comfortable braking function, non-linear trajectory planning is conducted on deceleration of the first vehicle, a planned target deceleration curve is obtained, then braking force of the first vehicle is corrected according to the target deceleration curve, and first target braking force is obtained; and finally, the first vehicle is controlled to brake according to the first target braking force. According to the embodiment of the invention, under the conditions that the braking distance is not increased and the pause feeling of the vehicle is avoided, the nodding phenomenon when the vehicle is braked and stopped can be obviously inhibited, so that the riding experience of a driver and passengers is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicles, and particularly relates to a vehicle braking method, device, equipment, storage medium and computer program product. Background Art

[0002] With the continuous progress of automotive automation technology, the braking system, as a core component of the active control system, directly affects the ride comfort. The function of the automotive comfort stop system (CST) aims to enhance the riding experience during braking, especially to suppress the "head nod" phenomenon of the vehicle body at the end of braking. The "head nod" phenomenon is caused by the elastic deformation of the suspension and tires due to inertia during braking, and the rebound of the vehicle body when stopping is transmitted to the passengers, causing discomfort.

[0003] Currently, existing CST solutions adjust the braking force by using a fixed linear or multi-segment linear pressure relief rate at the end of braking to reduce the "head nod" phenomenon. However, the fixed linear method may lead to too long braking distance or poor suppression effect; while the multi-segment linear method can improve the "head nod" phenomenon, but due to the multi-segment mutation of the braking force pressure relief rate, the braking force and deceleration are discontinuous, resulting in a braking "jerky feeling" and affecting the riding experience of passengers. Summary of the Invention

[0004] The present invention provides a vehicle braking method, device, equipment, storage medium and computer program product, which can significantly suppress the "head nod" phenomenon when the vehicle brakes to a stop without increasing the braking distance and avoiding the vehicle jerky feeling.

[0005] In a first aspect, an embodiment of the present application provides a vehicle braking method, the method including:

[0006] When a first vehicle triggers the comfort braking function, performing non-linear trajectory planning on the deceleration of the first vehicle to obtain a planned target deceleration curve;

[0007] Correcting the braking force of the first vehicle according to the target deceleration curve to obtain a first target braking force;

[0008] Controlling the braking of the first vehicle according to the first target braking force.

[0009] In a second aspect, an embodiment of the present application provides a vehicle braking device, the device including:

[0010] A planning module, configured to perform non-linear trajectory planning on the deceleration of the first vehicle to obtain a planned target deceleration curve when the first vehicle triggers the comfort braking function;

[0011] A correction module, configured to correct the braking force of the first vehicle according to the target deceleration curve to obtain a first target braking force;

[0012] A control module, configured to control the braking of a first vehicle according to a first target braking force.

[0013] In a third aspect, an embodiment of the present application provides an electronic device, which includes: a processor and a memory storing computer program instructions; when the processor executes the computer program instructions, the vehicle braking method as in the first aspect is implemented.

[0014] In a fourth aspect, an embodiment of the present application provides a computer storage medium, on which computer program instructions are stored, and when the computer program instructions are executed by a processor, the vehicle braking method as in the first aspect is implemented.

[0015] In a fifth aspect, an embodiment of the present application provides a computer program product, and when the instructions in the computer program product are executed by a processor of an electronic device, the electronic device is caused to execute the vehicle braking method as in the first aspect.

[0016] In a sixth aspect, an embodiment of the present application provides a vehicle, which includes at least one of the following:

[0017] A vehicle braking device as in any embodiment of the second aspect;

[0018] An electronic device as in any embodiment of the third aspect;

[0019] A computer storage medium as in any embodiment of the fourth aspect;

[0020] A computer program product as in any embodiment of the fifth aspect.

[0021] In the vehicle braking method, device, equipment, storage medium and computer program product according to the embodiments of the present application, by performing non-linear trajectory planning on the deceleration of the first vehicle, correcting the braking force of the first vehicle by using the planned target deceleration curve, obtaining the first target braking force and controlling the braking of the first vehicle according to the first target braking force. The embodiments of the present application adopt a non-linear deceleration trajectory planning method, compared with the fixed linear planning pressure relief slope, avoiding the problems of too long braking distance or insignificant suppression of the "nodding" phenomenon caused by linear planning; and compared with the multi-segment linear planning pressure relief slope, solving the problem of uncomfortable "jerks" caused by the discontinuous braking force due to the multi-segment linear planning pressure relief speed. In this way, the riding experience of the passengers is improved. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0023] Figure 1 is a schematic structural diagram of a vehicle braking system provided by an embodiment of the present application;

[0024] Figure 2 is a schematic flowchart of a vehicle braking method provided by an embodiment of the present application;

[0025] Figure 3 is a schematic flowchart of a method for determining whether a first vehicle triggers a comfort braking function provided by an embodiment of the present application;

[0026] Figure 4 is a schematic flowchart of a method for determining whether a first vehicle exits the comfort braking function provided by an embodiment of the present application;

[0027] Figure 5 is a speed-time graph of the first vehicle in three cases of not triggering the comfort braking function, triggering the comfort braking function by linear programming, and triggering the comfort braking function by non-linear programming provided by an embodiment of the present application;

[0028] Figure 6 is a deceleration-time graph of the first vehicle in three cases of not triggering the comfort braking function, triggering the comfort braking function by linear programming, and triggering the comfort braking function by non-linear programming provided by an embodiment of the present application;

[0029] Figure 7 is a braking distance-time graph of the first vehicle in three cases of not triggering the comfort braking function, triggering the comfort braking function by linear programming, and triggering the comfort braking function by non-linear programming provided by an embodiment of the present application;

[0030] Figure 8 is a schematic structural diagram of a vehicle braking device provided by an embodiment of the present application;

[0031] Figure 9 is a schematic structural diagram of an electronic device provided by an embodiment of the present application. Detailed implementation manners

[0032] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without some of these specific details. The following description of the embodiments is only intended to provide a better understanding of the present application by showing examples of the present application.

[0033] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0034] With the continuous progress of automotive automation technology, the braking system, as a core component of the active control system, directly affects the ride comfort. The function of the automotive comfort stop system (CST) is to improve the riding experience during braking, especially to suppress the "nodding" phenomenon of the vehicle body at the end of braking. The "nodding" phenomenon is caused by the elastic deformation of the suspension and tires due to inertia during braking, and when the vehicle stops, the rebound of the vehicle body is transmitted to the passengers, causing discomfort.

[0035] Currently, existing CST solutions adjust the braking force by using a fixed linear or multi-segment linear pressure relief rate at the end of braking to reduce the "nodding" phenomenon. However, the fixed linear method may result in too long braking distance or poor suppression effect; while the multi-segment linear method can improve the "nodding" phenomenon, but due to the multi-segment mutation of the pressure relief rate of the braking force, the braking force and deceleration are discontinuous, causing a "jerky feeling" during braking and affecting the riding experience of the passengers.

[0036] To solve the problems of the existing technology, the embodiments of the present application provide a vehicle braking method, device, equipment, storage medium and computer program product. By performing non-linear trajectory planning on the deceleration of the first vehicle, correcting the braking force of the first vehicle by using the planned target deceleration curve, obtaining the first target braking force and controlling the braking of the first vehicle according to the first target braking force. The embodiments of the present application adopt a non-linear deceleration trajectory planning method. Compared with the fixed linear planning pressure relief slope, it avoids the problems of too long braking distance or insignificant suppression of the "nodding" phenomenon caused by linear planning; and compared with the multi-segment linear planning pressure relief slope, it solves the problem of uncomfortable "jerky feeling" caused by the discontinuity of the braking force due to the multi-segment linear planning pressure relief speed. In this way, the riding experience of the passengers is improved.

[0037] It should be noted that the embodiments of the present application are implemented based on an electro-mechanical braking (EMB) system. The EMB system combines electronic and mechanical technologies to provide a safer, more efficient, and more environmentally friendly braking solution. The EMB system omits the traditional hydraulic system and is directly connected to the wheel motor through an electrical signal to achieve braking, making the braking control more precise and integrated. Thus, based on the EMB system, the target braking force of the vehicle can be corrected by planning a non-linear deceleration curve to achieve smooth braking, suppress the "nodding" phenomenon, and improve the riding experience of the passengers.

[0038] First, the vehicle braking system provided by the embodiments of the present application will be introduced below.

[0039] Figure 1 The structural schematic diagram of a vehicle braking system provided by an embodiment of the present application is shown. As Figure 1 shown, the vehicle braking system may include a data acquisition module 101, a comfort braking system state judgment module 102, a non-linear deceleration curve planning module 103, a comfort braking system control module 104, a brake control module 105, and a brake 106.

[0040] Among them, the data acquisition module 101 is used to acquire user operation information, road surface information, and dynamic information of the first vehicle.

[0041] The comfort braking system state judgment module 102 is used to receive the user operation information, road surface information, and dynamic information of the first vehicle acquired by the data acquisition module 101, and judge whether the first vehicle triggers or exits the comfort braking system according to the user operation information, road surface information, and dynamic information of the first vehicle.

[0042] The non-linear deceleration curve planning module 103 is used to perform non-linear trajectory planning on the deceleration of the first vehicle to obtain a target deceleration curve when it is determined that the first vehicle triggers the comfort braking system.

[0043] The comfort braking system control module 104 is used to correct the braking force at the end stage of the first vehicle according to the target deceleration curve output by the non-linear deceleration curve planning module 103.

[0044] The brake control module 105 is used to input a control instruction to the brake 106, and the control instruction includes a first target braking force.

[0045] The brake 106 is used to control the braking of the first vehicle according to the first target braking force.

[0046] Next, the vehicle braking method provided by the embodiments of the present application will be introduced.

[0047] Figure 2The flowchart of the vehicle braking method provided by an embodiment of the present application is shown. As Figure 2 shown, the method may include the following steps: S201 to S203.

[0048] S201: When the comfort braking function of the first vehicle is triggered, perform non-linear trajectory planning on the deceleration of the first vehicle to obtain the planned target deceleration curve.

[0049] Due to the influence of inertial force during the braking process of the vehicle, the suspension and tires will produce certain elastic deformations. Until the vehicle stops, the body will produce a certain amount of rebound due to the action of the suspension and tires, which is transmitted to the occupants, causing an uncomfortable sense of dizziness, that is, the "nodding" phenomenon. The comfort braking system (Comfort Stop, CST) function can effectively suppress the "nodding" phenomenon at the moment of vehicle stop by adjusting the braking force in the later stage of braking, so as to improve the riding comfort.

[0050] In some embodiments, performing non-linear trajectory planning on the deceleration of the first vehicle to obtain the planned target deceleration curve may be implemented by the non-linear deceleration curve planning module 103.

[0051] S202: Modify the braking force of the first vehicle according to the target deceleration curve to obtain the first target braking force.

[0052] In some embodiments, modifying the braking force of the first vehicle according to the target deceleration curve to obtain the first target braking force may be implemented by determining the first target braking force corresponding to the target deceleration curve according to the corresponding relationship between the deceleration curve and the braking force.

[0053] By modifying the braking force of the first vehicle according to the target deceleration curve to replace the braking force generated by the user's operation, the braking force of the first vehicle is modified, so as to realize precise control of the braking process of the first vehicle, and thus effectively suppress the "nodding" phenomenon.

[0054] S203: Control the braking of the first vehicle according to the first target braking force.

[0055] In some embodiments, controlling the braking of the first vehicle according to the first target braking force may be implemented by the brake 106 receiving and executing the control instruction sent by the brake control module 105.

[0056] In the embodiments of the present application, by performing non-linear trajectory planning on the deceleration of the first vehicle, the braking force of the first vehicle is corrected using the planned target deceleration curve to obtain the first target braking force, and the first vehicle is controlled to brake according to the first target braking force. The embodiments of the present application adopt a non-linear deceleration trajectory planning method. Compared with the fixed linear planning pressure relief slope, it avoids the problems of too long braking distance or insignificant suppression of the "nodding" phenomenon caused by linear planning; and compared with the multi-segment linear planning pressure relief slope, it solves the problem of uncomfortable "jerks" caused by the discontinuous braking force due to the multi-segment linear planning pressure relief speed. In this way, the riding experience of the passengers is improved.

[0057] In some embodiments, step S201 may include:

[0058] Obtain the initial deceleration, initial speed of the first vehicle when the comfort braking function is triggered, and the cumulative duration of triggering the comfort braking function;

[0059] Taking the simultaneous convergence of the initial deceleration and the initial speed to a first set value as the goal, determine the target deceleration curve corresponding to the initial deceleration, initial speed, and cumulative duration.

[0060] Wherein, the first set value may be zero.

[0061] Due to the deformation of the vehicle's suspension and tires caused by the inertial force generated by the deceleration in the later stage of braking, a rebound effect is further generated during parking, thereby generating the vehicle "nodding" phenomenon. That is, at the instant of braking to a stop, the vehicle speed is zero, but the deceleration is not zero.

[0062] Therefore, to suppress the "nodding" phenomenon, in this embodiment, by adopting the method of non-linear deceleration curve planning, on the basis of a small increase in the braking distance, the speed and deceleration of the vehicle at the time of braking to a stop can be simultaneously converged to zero, which can avoid the "nodding" phenomenon. At the same time, it can ensure that during the CST triggering process in the later stage of braking, there will be no multiple discontinuous mutations of the pressure relief slope, resulting in the generation of uncomfortable "jerks".

[0063] As an example, the correspondence between the initial deceleration, initial speed of the first vehicle when the comfort braking function is triggered, the cumulative duration of triggering the comfort braking function, and the deceleration curve can be shown as the following formula:

[0064] a CST =-ct 2 +a o (1)

[0065]

[0066] Wherein, a0 is the target deceleration generated by the driver operating the pedal at the moment of CST triggering, with the unit of m / s 2; a f is the planned target deceleration at the parking moment after CST trigger (usually 0), unit: m / s 2 ; a CST is the planned target deceleration varying with time after CST trigger, unit: m / s 2 ; v0 is the vehicle speed at the moment of CST trigger, unit: m / s; v CST is the target vehicle speed obtained by solving the planned target deceleration curve after CST trigger, unit: m / s; t is the cumulative time length after CST trigger (the value at the moment of triggering CST is 0), unit: s; c is the quadratic term coefficient of the CST non-linear quadratic polynomial deceleration curve planning

[0067] In some embodiments, aiming at the initial deceleration and the initial speed converging to the first set value simultaneously, determining the target deceleration curve corresponding to the initial deceleration, the initial speed and the cumulative duration may include:

[0068] Aiming at the initial deceleration and the initial speed converging to the first set value simultaneously, performing non-linear fitting on the relationship between the initial deceleration, the initial speed, the cumulative duration of triggering the comfort braking function and the deceleration curve, constructing a quadratic polynomial of the planned deceleration curve, and obtaining the corresponding relationship between the initial deceleration, the initial speed and the cumulative duration of triggering the comfort braking function and the deceleration curve;

[0069] Determining the target deceleration curve according to the corresponding relationship between the initial deceleration, the initial speed and the cumulative duration of triggering the comfort braking function and the deceleration curve.

[0070] As an example, aiming at the initial deceleration and the initial speed converging to the first set value simultaneously, the specific process of performing non-linear fitting on the relationship between the initial deceleration, the initial speed, the cumulative duration of triggering the comfort braking function and the deceleration curve and constructing a quadratic polynomial of the planned deceleration curve can be illustrated as follows:

[0071] Assume that the target deceleration generated by the user operating the pedal at the moment of triggering CST at the end of braking is a0, and the vehicle speed of the car is v0. Then the non-linear quadratic polynomial deceleration curve planning formula is as follows, where c is the term to be determined and solved:

[0072] a CST =-ct 2 +a o (3)

[0073] Based on the above deceleration planning curve and the vehicle parameters at the time of triggering, the vehicle speed planning formula during the CST trigger process can be deduced as follows:

[0074]

[0075] Assume that when the vehicle speed is 0 during parking, the vehicle deceleration is a f , according to the deceleration planning curve formula, the cumulative time t from CST trigger to stop f is:

[0076]

[0077] At this time, substitute the above formula into the vehicle speed planning curve to solve the undetermined coefficient term c as follows:

[0078]

[0079] where a f usually takes the value of 0, which means that when the braking stop speed of the first vehicle is 0, the expected target deceleration converges to 0 at the same time. At this time, the rebound effect of the suspension and tires affected by the inertial force is the smallest, the "nodding" phenomenon is most significantly suppressed, and the comfort level is the highest.

[0080] In some embodiments, the vehicle braking method may further include:

[0081] When the first vehicle triggers the comfort braking function, obtain the real-time deceleration curve of the first vehicle;

[0082] Determine the deceleration error between the real-time deceleration curve and the target deceleration curve;

[0083] According to the deceleration error, determine the compensation value of the target deceleration curve;

[0084] Adjust the target deceleration curve according to the compensation value.

[0085] Due to the parameter inaccuracies of the braking actuator and the vehicle model and the irregular disturbances caused by the road surface or environment, there will inevitably be a control tracking error between the actual vehicle deceleration magnitude and the expected deceleration planning curve. Specifically, it can be manifested in the following three situations:

[0086] (1) If the actual vehicle deceleration magnitude is higher than the expected deceleration curve, the actual stop time will be earlier than the planned stop time t f , and at the same time, the deceleration magnitude at the moment of stop will be greater than the expected stop deceleration magnitude a f , and at this time, an unexpected "nodding" phenomenon during parking will occur, reducing the comfort.

[0087] (2) If the actual vehicle deceleration magnitude is lower than the expected deceleration curve, the actual stop time will be later than the planned stop time t f, an unexpected stopping distance will be generated at this time, reducing safety. Although it is possible to determine through logical detection that in this situation, the brake actuator rebuilds pressure, but at this time, an unexpected instantaneous deceleration during stopping, i.e., the "nodding" phenomenon during stopping, will also be generated, reducing comfort.

[0088] (3) If the actual vehicle deceleration magnitude frequently crosses the desired deceleration curve, an uncomfortable "jerky feeling" during the braking process will be generated due to the oscillating change of the deceleration at this time. At the same time, it is difficult to ensure the deceleration magnitude at the instant of stopping, reducing comfort.

[0089] By determining the deceleration error between the real-time deceleration curve and the target deceleration curve of the first vehicle, and determining the compensation value of the target deceleration curve according to the deceleration error, and adjusting the target deceleration curve based on the compensation value, it is possible to avoid the "nodding" phenomenon during stopping caused by the tracking error between the actual vehicle deceleration magnitude and the desired deceleration planning curve or the uncomfortable "jerky feeling" during the braking process caused by the oscillating change of the deceleration, thereby ensuring the comfort of the user when driving the vehicle.

[0090] As an example, adjusting the target deceleration curve according to the compensation value can be to perform scaling adjustment by multiplying the target deceleration curve by the corresponding compensation value based on fuzzy logic rule judgment.

[0091] In some embodiments, before performing non-linear trajectory planning on the deceleration of the first vehicle to obtain the planned target deceleration curve when the first vehicle triggers the comfort braking function, the vehicle braking method may further include:

[0092] Obtain user control information, road surface information, and the dynamic information of the first vehicle; the user control information includes the braking demand and the steering wheel rotation angle, and the dynamic information includes the current speed of the first vehicle, the function state of the anti-lock braking system, the function state of the electronic stability control system, and the brake pressure build-up working state;

[0093] When the first preset condition is met, it is determined that the first vehicle triggers the comfort braking function. The first preset condition includes:

[0094] The braking demand is less than the preset demand threshold;

[0095] The steering wheel rotation angle of the first vehicle is less than the first preset angle threshold;

[0096] The road surface information indicates that the road surface is a uniform road surface;

[0097] The current speed of the first vehicle is less than the preset speed threshold;

[0098] The function state of the anti-lock braking system is the untriggered state;

[0099] The function state of the electronic stability control system is the untriggered state;

[0100] The pressure - building working state of the braking system is in a normal state.

[0101] Among them, the preset demand threshold, the first preset angle threshold, and the preset speed threshold can be set manually and will not be elaborated here.

[0102] The braking demand can include the desired braking intensity. The first preset condition can include that the desired braking intensity is less than the first preset intensity threshold, and the first preset intensity threshold can be set manually.

[0103] A uniform road surface refers to a road surface that is highly uniform in terms of materials, structure, surface characteristics, and performance, etc., and can provide safe, comfortable, and efficient driving conditions for vehicles.

[0104] In some embodiments, to determine whether a road surface is a uniform road surface, it can be determined by obtaining the adhesion of the first vehicle on the road surface and the slope of the road surface, and based on the adhesion of the first vehicle on the road surface and the slope of the road surface. For example, when there are continuous changes in the slope of the road surface and the adhesion of the first vehicle on the road surface shows frequent differences in the degree of adhesion, it can be determined that the road surface is not uniform. Otherwise, it is a uniform road surface.

[0105] The pressure - building working state of the braking system being in a normal state means that the braking system can normally build and maintain the required hydraulic pressure or air pressure during braking, ensuring stable and reliable braking effects.

[0106] Among them, the first preset condition includes that the braking demand is less than the preset demand threshold, the steering wheel rotation angle of the first vehicle is less than the first preset angle threshold, the current speed is less than the preset speed threshold, and the functional states of both the anti - lock braking system and the electronic stability control system are in an untriggered state. This is because when the braking demand is greater than the preset demand threshold, the steering wheel rotation angle of the first vehicle is greater than the first preset angle threshold, the speed is greater than the preset speed threshold, and the functional states of both the anti - lock braking system and the electronic stability control system are in a triggered state, it indicates that the user is performing an emergency braking or other emergency operations. In this case, comfort is no longer the primary consideration of the user, but it is necessary to first meet the user's emergency braking demand to ensure that the vehicle decelerates or stops quickly, thereby ensuring the safety of the whole vehicle.

[0107] By determining that the first vehicle triggers the comfort braking function when the first preset condition is met, it can provide a comfortable driving experience for the user on the premise of avoiding potential safety hazards of the first vehicle, and can improve the safety of the user's driving.

[0108] As an example, as Figure 3 shown, to determine whether the first vehicle triggers the comfort braking function, it can include the following steps:

[0109] S301: The user steps on the brake pedal.

[0110] S302: Determine whether the current speed is less than a preset speed threshold; if so, proceed to step S303.

[0111] S303: Determine whether the function status of the anti-lock braking system is in an untriggered state; if so, proceed to step S304.

[0112] S304: Determine whether the function status of the electronic stability control system is in an untriggered state; if so, proceed to step S305.

[0113] S305: Determine whether the steering wheel rotation angle is less than a first preset angle threshold; if so, proceed to step S306.

[0114] S306: Determine whether the desired braking intensity is less than a first preset intensity threshold; if so, proceed to step S307.

[0115] S307: Determine whether the road surface is a uniform road surface; if so, proceed to step S308.

[0116] S308: Determine whether the road surface gradient is less than a preset gradient threshold; if so, proceed to step S309.

[0117] S309: Determine whether the pressure build-up working state of the braking system is in a normal state; if so, proceed to step S310.

[0118] S310: Determine to trigger the comfort braking function.

[0119] In some embodiments, in order to accurately determine whether the first vehicle exits the comfort braking function, after determining that the first vehicle triggers the comfort braking function, the vehicle braking method may further include:

[0120] Obtain the initial desired braking intensity and the initial steering wheel rotation angle of the first vehicle, as well as the current desired braking intensity and the current steering wheel rotation angle of the first vehicle;

[0121] Determine a first change value of the desired braking intensity according to the current desired braking intensity and the initial desired braking intensity; determine a second change value of the steering wheel rotation angle according to the current steering wheel rotation angle and the initial steering wheel rotation angle;

[0122] Determine that the first vehicle exits the comfort braking function when any of the following conditions is met:

[0123] The first preset condition is not satisfied;

[0124] The speed of the first vehicle is zero;

[0125] The cumulative duration for which the first vehicle triggers the comfort braking function is greater than a preset duration threshold;

[0126] The first change value is greater than a second preset intensity threshold, and / or the second change value is greater than a second preset angle threshold.

[0127] Wherein, the speed of the first vehicle being zero means that the first vehicle is in a stopped state. When the first vehicle is in a stopped state, the braking process ends and the comfort braking function will be exited.

[0128] As an example, to determine whether the speed of the first vehicle is zero, it can be achieved by obtaining the data of the speed sensor of the first vehicle.

[0129] Among them, the preset duration threshold, the second preset intensity threshold, and the second preset angle threshold can be set manually and will not be elaborated here.

[0130] As an example, to determine the first change value of the desired braking intensity based on the current desired braking intensity and the initial desired braking intensity, the first change value of the desired braking intensity can be determined by calculating the difference between the current desired braking intensity and the initial desired braking intensity.

[0131] As an example, to determine the second change value of the steering wheel rotation angle based on the current steering wheel rotation angle and the initial steering wheel rotation angle, the second change value of the steering wheel rotation angle can be determined by calculating the difference between the current steering wheel rotation angle and the initial steering wheel rotation angle.

[0132] As an example, as Figure 4 shown, to determine whether the first vehicle exits the comfort braking function, the following steps can be included:

[0133] S401: Determine that the comfort braking function is triggered. After that, simultaneously perform steps S402, S403, and S404.

[0134] S402: Determine whether the speed is zero; if so, perform step S405.

[0135] S403: Determine whether the cumulative duration for which the comfort braking function is triggered is greater than the preset duration threshold; if so, perform step S405.

[0136] S404: Determine whether the first change amount is greater than the second preset intensity threshold and whether the second change value is greater than the second preset angle threshold; if so, perform step S405.

[0137] S405: Determine to exit the comfort braking function.

[0138] In some embodiments, after the first vehicle exits the comfort braking function, the vehicle braking method may further include:

[0139] Obtain the real-time speed of the first vehicle;

[0140] When the real-time speed of the first vehicle is greater than the preset speed threshold, return to obtain user control information, road surface information, and dynamic information of the first vehicle; the user control information includes the desired braking intensity and the steering wheel rotation angle, and the dynamic information includes the current speed of the first vehicle, the function status of the anti-lock braking system, the function status of the electronic stability control system, and the brake pressure build-up working status;

[0141] When the first preset condition is met, determine that the first vehicle triggers the comfort braking function.

[0142] In some embodiments, based on any of the above embodiments, the vehicle braking method may further include:

[0143] Obtain user control information, where the user control information includes the desired braking intensity;

[0144] According to the correspondence between the desired braking intensity and the second target braking force, determine the second target braking force corresponding to the desired braking intensity;

[0145] When the first vehicle does not trigger the comfort braking function, control the vehicle braking according to the second target braking force.

[0146] Wherein, the desired braking intensity represents the braking intensity generated by user control.

[0147] As an example, obtaining the user's desired braking intensity may be by obtaining the pedal opening of the first vehicle and determining the desired braking intensity according to the pedal opening.

[0148] When the first vehicle does not trigger the comfort braking function, it indicates that comfort is not within the scope of the user's braking demand consideration. At this time, the second target braking force is determined by analyzing the user's control information, and the first vehicle is controlled to brake with the second target braking force as the target, so as to ensure that the first vehicle stops braking normally.

[0149] In order to better illustrate the beneficial effects of the solution of the present application, based on the above embodiments, a specific example is given.

[0150] Assume that the user steps on the brake pedal and keeps it constant, and the braking intention is parsed as 0.3g (i.e., a0 = 0.3g), the initial vehicle braking speed v 00 = 18 km / h, the speed threshold at the CST trigger moment is v0 = 6 km / h, and the target deceleration a at the CST braking stop moment f= 0, and all other CST trigger conditions are satisfied. By comparing the three cases of non-triggered CST, CST triggered by linear programming, and CST triggered by non-linear programming respectively, their expected speeds, expected target deceleration trajectories, and expected braking distances (theoretical values without considering brake response errors) are shown in the following figures:

[0151] As Figures 5 - 7 shown, during the braking process of CST, when the vehicle speed is less than the CST trigger speed threshold v0 = 6 km / h, the comfort braking function will be activated, and a new target deceleration trajectory will be regenerated to replace the target deceleration generated based on the user's intention. Since CST only intervenes in the control at the end of braking, the increase in braking distance after triggering CST is not significant compared to that without triggering CST. And after triggering CST, when the vehicle speed is 0 at the moment of braking to a stop, the magnitude of the vehicle deceleration smoothly converges to 0. That is, in a safe situation, the "nodding" phenomenon is significantly suppressed, and the braking comfort level is improved.

[0152] It should be noted that compared with the linear deceleration planning, the CST based on non-linear deceleration planning has a shorter braking distance and higher safety while being able to suppress the "nodding" phenomenon. Although the multi-segment linearized deceleration planning can approximately achieve the effect of non-linear deceleration planning, the segmented operation increases the difficulty of debugging and design. At the same time, the discontinuous deceleration planning caused by multi-segment linearization will cause a "jerky feeling" during the braking process. Therefore, the CST control based on non-linear deceleration planning better solves the above problems.

[0153] At the same time, for the convenience of design and debugging, according to the user's intention and road surface information, and combined with the user's personalized needs, by presetting the speed threshold v0 and the target deceleration a f at the stop moment, the CST target deceleration trajectory can be adaptively generated.

[0154] Figure 8 is a schematic structural diagram of a vehicle braking device 800 provided by an embodiment of the present application. As Figure 8 shown, the device may include a planning module 810, a correction module 820, and a control module 830.

[0155] The planning module 810 is configured to perform non-linear trajectory planning on the deceleration of the first vehicle when the comfort braking function of the first vehicle is triggered, so as to obtain a planned target deceleration curve;

[0156] The correction module 820 is configured to correct the braking force of the first vehicle according to the target deceleration curve to obtain a first target braking force;

[0157] The control module 830 is configured to control the braking of the first vehicle according to the first target braking force.

[0158] In the embodiments of the present application, by performing non-linear trajectory planning on the deceleration of the first vehicle, the braking force of the first vehicle is corrected using the planned target deceleration curve, and the first target braking force is obtained and the first vehicle is controlled to brake according to the first target braking force. The embodiments of the present application adopt a non-linear deceleration trajectory planning method. Compared with the fixed linear planning pressure relief slope, it avoids the problems of too long braking distance or insignificant suppression of the "nodding" phenomenon caused by linear planning; and compared with the multi-segment linear planning pressure relief slope, it solves the problem of uncomfortable "jerks" caused by the discontinuous braking force due to the multi-segment linear planning pressure relief speed. In this way, the riding experience of the passengers is improved.

[0159] In some embodiments, the vehicle braking device 800 further includes an acquisition module;

[0160] The acquisition module is configured to acquire the initial deceleration, the initial speed, and the cumulative duration of triggering the comfort braking function when the first vehicle triggers the comfort braking function;

[0161] The planning module 810 is further configured to determine a target deceleration curve corresponding to the initial deceleration, the initial speed, and the cumulative duration according to the correspondence relationship between the initial deceleration, the initial speed, and the cumulative duration of triggering the comfort braking function and the deceleration curve.

[0162] In some embodiments, the acquisition module is further configured to acquire the initial deceleration, the initial speed, and the cumulative duration of triggering the comfort braking function when the preset vehicle triggers the comfort braking function before determining the target deceleration curve corresponding to the initial deceleration, the initial speed, and the cumulative duration according to the correspondence relationship between the initial deceleration, the initial speed, and the cumulative duration of triggering the comfort braking function and the deceleration curve;

[0163] The planning module 810 is further configured to non-linearly fit the relationship between the initial deceleration, the initial speed, and the cumulative duration of triggering the comfort braking function and the deceleration curve with the goal of simultaneously converging the initial deceleration and the initial speed to the first set value, construct a quadratic polynomial of the planned deceleration curve, and obtain the correspondence relationship between the initial deceleration, the initial speed, and the cumulative duration of triggering the comfort braking function and the deceleration curve.

[0164] In some embodiments, the vehicle braking device 800 further includes a judgment module;

[0165] The acquisition module is further configured to obtain user control information, road surface information, and the dynamic information of the first vehicle before performing non-linear trajectory planning on the deceleration of the first vehicle to obtain the planned target deceleration curve when the first vehicle triggers the comfort braking function; the user control information includes the desired braking intensity and the steering wheel rotation angle, the road surface information includes the road surface condition and the slope, and the dynamic information of the vehicle includes the current speed of the first vehicle, the function state of the anti-lock braking system, the function state of the electronic stability control system, and the brake pressure build-up working state;

[0166] The judgment module is configured to determine that the first vehicle triggers the comfort braking function when the first preset condition is met. The first preset condition includes:

[0167] The desired braking intensity is less than the first preset intensity threshold;

[0168] The steering wheel rotation angle of the first vehicle is less than the first preset angle threshold;

[0169] The road surface condition is a uniform road surface and the slope is less than the preset slope threshold;

[0170] The current speed of the first vehicle is less than the preset speed threshold;

[0171] The function state of the anti-lock braking system is an untriggered state;

[0172] The function state of the electronic stability control system is an untriggered state;

[0173] The brake system pressure build-up working state is a normal state.

[0174] In some embodiments, the vehicle braking device 800 further includes a calculation module;

[0175] The acquisition module is further configured to obtain the initial desired braking intensity and the initial steering wheel rotation angle when the first vehicle triggers the comfort braking function, as well as the current desired braking intensity and the current steering wheel rotation angle of the first vehicle after determining that the first vehicle triggers the comfort braking function;

[0176] The calculation module is configured to determine the first change value of the desired braking intensity according to the current desired braking intensity and the initial desired braking intensity; and determine the second change value of the steering wheel rotation angle according to the current steering wheel rotation angle and the initial steering wheel rotation angle;

[0177] The judgment module is further configured to determine that the first vehicle exits the comfort braking function when any of the following conditions is met:

[0178] The first preset condition is not met;

[0179] The speed of the first vehicle is zero;

[0180] The cumulative duration for which the first vehicle triggers the comfort braking function is greater than a preset duration threshold;

[0181] The first change value is greater than a second preset intensity threshold, and / or the second change value is greater than a second preset angle threshold.

[0182] In some embodiments, the calculation module is further configured to determine a second target braking force corresponding to the desired braking intensity according to the correspondence between the desired braking intensity and the second target braking force;

[0183] The control module 830 is further configured to control the vehicle braking according to the second target braking force when the first vehicle does not trigger the comfort braking function.

[0184] Figure 8 Each module in the shown device can implement Figure 2 each step in, and achieve the corresponding technical effects, which will not be described in detail here for the sake of brevity.

[0185] Figure 9 shows a schematic hardware structure diagram of an electronic device provided in an embodiment of the present application.

[0186] The electronic device may include a processor 901 and a memory 902 storing computer program instructions.

[0187] Specifically, the above-mentioned processor 901 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0188] The memory 902 may include a mass storage for data or instructions. By way of example and not limitation, the memory 902 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In a suitable case, the memory 902 may include a removable or non-removable (or fixed) medium. In a suitable case, the memory 902 may be internal or external to the integrated gateway disaster recovery device. In a specific embodiment, the memory 902 is a non-volatile solid state memory.

[0189] In a particular embodiment, the memory may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage media device, an optical storage media device, a flash memory device, an electrical, optical, or other physical / tangible memory storage device. Thus, generally, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to one aspect of the present application.

[0190] The processor 901 realizes any one of the vehicle braking methods in the above embodiments by reading and executing the computer program instructions stored in the memory 902.

[0191] In one example, the electronic device may further include a communication interface 903 and a bus 910. Among them, as Figure 9 shown, the processor 901, the memory 902, and the communication interface 903 are connected through the bus 910 to complete the communication with each other.

[0192] The communication interface 903 is mainly used to realize the communication between each module, device, unit, and / or device in the embodiments of the present application.

[0193] The bus 910 includes hardware, software, or both, and couples the components of the electronic device to each other. By way of example and not limitation, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an InfiniBand interconnect, a Low Pin Count (LPC) bus, a memory bus, a MicroChannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses or a combination of two or more of these. In a suitable case, the bus 910 may include one or more buses. Although the embodiments of the present application describe and illustrate specific buses, the present application contemplates any suitable bus or interconnect.

[0194] In addition, in combination with the vehicle braking method in the above embodiments, the embodiments of the present application may provide a computer storage medium to implement. Computer program instructions are stored on the computer storage medium; when the computer program instructions are executed by a processor, any one of the vehicle braking methods in the above embodiments is realized.

[0195] The embodiments of the present application also provide a computer program product, including a computer program, and when the computer program is executed by a processor, any one of the vehicle braking methods in the above embodiments is realized.

[0196] In addition, embodiments of the present application further provide a vehicle, which may include at least one of the following:

[0197] A vehicle braking device as in any of the embodiments of the second aspect;

[0198] An electronic device as in any of the embodiments of the third aspect;

[0199] A computer-readable storage medium as in any of the embodiments of the fourth aspect;

[0200] A computer program product as in any of the embodiments of the fifth aspect. Details are not described herein again.

[0201] It should be clear that the present application is not limited to the specific configurations and processes described above and illustrated in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and illustrated as examples. However, the method process of the present application is not limited to the specific steps described and illustrated, and those skilled in the art can make various changes, modifications, and additions, or change the order between steps after understanding the spirit of the present application.

[0202] The functional blocks shown in the above structure block diagrams can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, and so on. When implemented in software, the elements of the present application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium or transmitted through a data signal carried in a carrier wave on a transmission medium or a communication link. "Machine-readable medium" can include any medium that can store or transmit information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical discs, hard disks, fiber optic media, radio frequency (RF) links, and so on. The code segment can be downloaded via a computer network such as the Internet, an intranet, and so on.

[0203] It should also be noted that the exemplary embodiments mentioned in the present application describe some methods or systems based on a series of steps or devices. However, the present application is not limited to the order of the above steps, that is, the steps can be executed in the order mentioned in the embodiments, or different from the order in the embodiments, or several steps can be executed simultaneously.

[0204] As described above with reference to the flowcharts and / or block diagrams of methods, apparatuses, devices, storage media, and computer program products according to embodiments of the present application. It should be understood that each block in the flowchart and / or block diagram, and the combination of blocks 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, or other programmable data processing device to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the functions / actions specified in one or more blocks of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It should also be understood that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can also be implemented by dedicated hardware that performs the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0205] As described above, the above is only the specific implementation manner of the present application. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, modules, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein. It should be understood that the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present application.

Claims

1. A vehicle braking method, characterized in that, Including: When the comfort braking function is triggered by the first vehicle, performing non-linear trajectory planning on the deceleration of the first vehicle to obtain a planned target deceleration curve; Correcting the braking force of the first vehicle according to the target deceleration curve to obtain a first target braking force; Controlling the braking of the first vehicle according to the first target braking force.

2. The method according to claim 1, characterized in that, When the comfort braking function is triggered by the first vehicle, performing non-linear trajectory planning on the deceleration of the first vehicle to obtain a planned target deceleration curve, including: Obtaining the initial deceleration, initial speed when the first vehicle triggers the comfort braking function, and the cumulative duration of triggering the comfort braking function; Taking the simultaneous convergence of the initial deceleration and the initial speed to a first set value as the goal, and determining a target deceleration curve corresponding to the initial deceleration, initial speed, and the cumulative duration.

3. The method according to claim 2, characterized in that Taking the simultaneous convergence of the initial deceleration and the initial speed to a first set value as the goal, and determining a target deceleration curve corresponding to the initial deceleration, initial speed, and the cumulative duration, including: Taking the simultaneous convergence of the initial deceleration and the initial speed to a first set value as the goal, performing non-linear fitting on the relationship between the initial deceleration, initial speed, the cumulative duration of triggering the comfort braking function, and the deceleration curve, to obtain the corresponding relationship between the initial deceleration, initial speed when triggering the comfort braking function, the cumulative duration of triggering the comfort braking function, and the deceleration curve; Determining the target deceleration curve according to the corresponding relationship between the initial deceleration, initial speed when triggering the comfort braking function, the cumulative duration of triggering the comfort braking function, and the deceleration curve.

4. The method according to claim 1, wherein Before performing non-linear trajectory planning on the deceleration of the first vehicle to obtain a planned target deceleration curve when the comfort braking function is triggered by the first vehicle, the method further includes: Obtaining user control information and the dynamic information of the first vehicle; the user control information includes a braking demand, and the dynamic information includes the current speed of the first vehicle; When a first preset condition is satisfied, determining that the first vehicle triggers the comfort braking function, and the first preset condition includes: The braking demand is less than a preset demand threshold; The current speed of the first vehicle is less than a preset speed threshold.

5. The method according to claim 4, wherein After determining that the first vehicle triggers the comfort braking function, the method further includes: Obtaining the initial expected braking intensity, initial steering wheel rotation angle of the first vehicle, and the current expected braking intensity and current steering wheel rotation angle of the first vehicle; Determining a first change value of the expected braking intensity according to the current expected braking intensity and the initial expected braking intensity; determining a second change value of the steering wheel rotation angle according to the current steering wheel rotation angle and the initial steering wheel rotation angle; When the first change value is greater than a second preset intensity threshold, and / or, the second change value is greater than a second preset angle threshold, determining that the first vehicle exits the comfort braking function.

6. The method according to claim 1, wherein The method further includes: When the comfort braking function is triggered by the first vehicle, obtain the real-time deceleration curve of the first vehicle; Determine the deceleration error between the real-time deceleration curve and the target deceleration curve; Determine the compensation value of the target deceleration curve according to the deceleration error; Adjust the target deceleration curve according to the compensation value.

7. The method according to any one of claims 1-6, characterized in that, The method further includes: Obtain user control information, where the user control information includes the desired braking intensity; Determine the second target braking force corresponding to the desired braking intensity according to the correspondence between the desired braking intensity and the second target braking force; When the comfort braking function is not triggered by the first vehicle, control the braking of the first vehicle according to the second target braking force.

8. A vehicle braking device, characterized in that, The device includes: A planning module, configured to perform non-linear trajectory planning on the deceleration of the first vehicle when the comfort braking function of the first vehicle is triggered, to obtain a planned target deceleration curve; A correction module, configured to correct the braking force of the first vehicle according to the target deceleration curve to obtain a first target braking force; A control module, configured to control the braking of the first vehicle according to the first target braking force.

9. A computer-readable storage medium, characterized in that, Computer program instructions are stored on the computer-readable storage medium, and when the computer program instructions are executed by a processor, the vehicle braking method according to any one of claims 1-7 is implemented.

10. A vehicle, characterized in that, Including at least one of the following: The vehicle braking device according to claim 8; The computer-readable storage medium according to claim 9.

Images