A method and apparatus for early warning of braking performance

Abstract

The embodiment of the present application provides a kind of brake performance early warning method and device, the method comprises: obtaining the travel data collected when braking in the process of automatic driving of vehicle;Determine the current braking scene, and according to the current braking scene, determine whether the travel data triggers the early warning condition for brake performance;In the case where the vehicle triggers the early warning condition for brake performance, generate the first early warning message for brake performance.Through the embodiment of the present application, brake performance early warning is realized according to the travel data of vehicle braking, on the one hand, it can adapt to brake module of different vehicle models, different structures, different materials, on the other hand, without reaching the set thickness threshold, the whole process of brake performance change can be early warned, and the sensitivity is higher, and by using different early warning strategies according to braking scene, it can be adapted to the situation beyond normal braking.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vehicles, in particular to a brake performance early warning method and device. BACKGROUND

[0002] For vehicles, brake performance is an important factor affecting safe driving. In the process of vehicle braking, through the conversion of kinetic energy into heat energy, after the brake system sends a brake signal, the piston pushes the brake caliper, the brake pad exerts pressure on the brake disc, and a large friction force is generated between the two. In the process of friction, the kinetic energy of the rotating wheel is gradually converted into heat energy on the brake disc, and finally the effect of slowing down the vehicle is achieved. However, as the mileage of the vehicle increases, the brake pad will be continuously worn in the friction process due to the vehicle's braking operation, and the brake performance will gradually decrease. In order to ensure safe driving, it is necessary to monitor and warn the brake performance of the vehicle in order to replace the brake pad in time.

[0003] In the prior art, the wear degree of the brake pad is determined by monitoring the thickness change of the brake pad, and the brake performance of the vehicle is determined. When the brake pad is worn to the limit position, the sensing line will automatically connect the circuit, and the fault light will be turned on.

[0004] However, this method has the following disadvantages:

[0005] 1. Poor adaptability to brake modules of different vehicle models, different structures and different materials.

[0006] 2. The warning is based on the thickness of the brake pad. As long as the thickness threshold is not reached, even if the brake performance is severely degraded, the warning will not be triggered, and the sensitivity is low.

[0007] 3. Poor adaptability to situations beyond normal braking, such as emergency braking. SUMMARY

[0008] In view of the above problems, a brake performance early warning method and device are provided to overcome the above problems or at least partially solve the above problems, comprising:

[0009] A brake performance early warning method, the method comprising:

[0010] Obtaining driving data collected when braking in the process of automatic driving of a vehicle;

[0011] Determining a current braking scenario, and determining whether the driving data triggers a brake performance warning condition according to the current braking scenario;

[0012] Generating a first brake performance warning message in the case that the vehicle triggers a brake performance warning condition.

[0013] Optionally, the determining whether the driving data triggers the warning condition for the braking performance according to the current braking scenario comprises:

[0014] In a case where the current braking scenario is a specified braking scenario, acquiring position data collected in a process of automatically driving the vehicle;

[0015] In combination with the position data, determining whether the driving data triggers the warning condition for the braking performance.

[0016] Optionally, the determining whether the driving data triggers the warning condition for the braking performance in combination with the position data comprises:

[0017] In a case where the current braking scenario is an emergency braking scenario, determining whether a current road condition is a non-specified road condition according to the position data;

[0018] In a case where the current road condition is the non-specified road condition, determining an average deceleration of the vehicle according to the driving data;

[0019] In a case where the average deceleration is less than a preset deceleration, determining that the vehicle triggers the warning condition for the braking performance.

[0020] Optionally, the determining whether the driving data triggers the warning condition for the braking performance in combination with the position data comprises:

[0021] In a case where the current braking scenario is a high-frequency braking scenario, determining a braking energy efficiency ratio according to the driving data;

[0022] In a case where the braking energy efficiency ratio is greater than or equal to the preset energy efficiency ratio, determining a remaining braking road length according to the position data;

[0023] In a case where the braking energy efficiency ratio is unable to complete braking of the remaining braking road length, determining that the vehicle triggers the warning condition for the braking performance.

[0024] Optionally, before the determining that the vehicle triggers the warning condition for the braking performance in the case where the braking energy efficiency ratio is unable to complete braking of the remaining braking road length, the method further comprises:

[0025] Determining braking energy efficiency attenuation data according to the braking energy efficiency ratio;

[0026] Predicting whether the braking energy efficiency ratio is able to complete braking of the remaining braking road length according to the braking energy efficiency attenuation data.

[0027] Optionally, the method further comprises:

[0028] In a case where the brake energy efficiency ratio is less than the preset energy efficiency ratio, it is determined that the vehicle triggers a pre-warning condition for brake performance.

[0029] Optionally, the method further comprises:

[0030] According to the driving data, updating a total brake loss amount;

[0031] In a case where the total brake loss amount is greater than a preset loss amount, a second pre-warning message for brake performance is generated.

[0032] A pre-warning device for brake performance, comprising:

[0033] A driving data acquisition module is configured to acquire driving data collected when braking during automatic driving of a vehicle;

[0034] A pre-warning condition trigger judgment module is configured to determine a current braking scenario, and determine whether the driving data triggers a pre-warning condition for brake performance according to the current braking scenario;

[0035] A first pre-warning message generation module is configured to generate a first pre-warning message for brake performance in a case where the vehicle triggers a pre-warning condition for brake performance.

[0036] An electronic device comprises a processor, a memory, and a computer program stored on the memory and capable of running on the processor, and the computer program, when executed by the processor, implements the pre-warning method for brake performance as described above.

[0037] A computer readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the pre-warning method for brake performance as described above.

[0038] Embodiments of the present application have the following advantages:

[0039] In embodiments of the present application, by acquiring driving data collected when braking during automatic driving of a vehicle, determining a current braking scenario, determining whether the driving data triggers a pre-warning condition for brake performance according to the current braking scenario, and generating a first pre-warning message for brake performance in a case where the vehicle triggers a pre-warning condition for brake performance, a pre-warning for brake performance is realized according to driving data of vehicle braking. Since it does not depend on monitoring of brake pad thickness, on the one hand, it can adapt to brake modules of different vehicle models, different structures, and different materials, and on the other hand, it does not need to reach a set thickness threshold, can pre-warn the whole process of brake performance change, has high sensitivity, and by using different pre-warning strategies according to braking scenarios, it can adapt to situations beyond normal braking. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the present application, the drawings needed to be used in the description of the present application will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0041] Figure 1a is an architecture diagram of a brake performance early warning provided by an embodiment of the present application;

[0042] Figure 1b is a schematic diagram of an acceleration change curve provided by an embodiment of the present application;

[0043] Figure 2 is a step flow chart of a brake performance early warning method provided by an embodiment of the present application;

[0044] Figure 3a is a step flow chart of another brake performance early warning method provided by an embodiment of the present application;

[0045] Figure 3b is a flow chart of an emergency braking scenario early warning provided by an embodiment of the present application;

[0046] Figure 4a is a step flow chart of another brake performance early warning method provided by an embodiment of the present application;

[0047] Figure 4b is a flow chart of a high-frequency braking scenario early warning provided by an embodiment of the present application;

[0048] Figure 4c is a flow chart of another high-frequency braking scenario early warning provided by an embodiment of the present application;

[0049] Figure 5a is a step flow chart of another brake performance early warning method provided by an embodiment of the present application;

[0050] Figure 5b is a flow chart of a brake loss total early warning provided by an embodiment of the present application;

[0051] Figure 6 is a structure block diagram of a brake performance early warning device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to make the above objectives, characteristics and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below in combination with the drawings and specific embodiments. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0053] In the process of automatic driving of the vehicle, driving data is collected through the brake signal monitoring system and the inertial navigation unit (IMU), and then the driving data can be used to realize the brake performance warning of the automatic driving vehicle, mainly including the following aspects:

[0054] 1. When the vehicle is in emergency braking, it is judged whether the deceleration requirement of the emergency braking is triggered.

[0055] 2. When the vehicle is in high-frequency braking operation, the residual performance margin of the brake system is estimated, and a warning signal is sent out to remind, so as to reduce the braking frequency.

[0056] 3. The braking force applied by the system and the braking duration are counted during each braking, and the brake consumption amount of each braking process is generated.

[0057] In specific implementation, Figure 1a When the automatic driving vehicle needs to perform braking operation according to the judgment of the vehicle end system, a brake signal can be sent to the braking system. When the brake signal is detected, the vehicle state monitoring system and the inertial navigation unit can be activated, and then the collected vehicle acceleration, vehicle speed, driving distance and other driving data are sent to the data platform. The data platform performs emergency braking performance warning, high-frequency braking leading to brake performance degradation warning, brake consumption total amount warning and other warning operations after analysis.

[0058] Among them, the inertial measurement unit can feedback the current vehicle acceleration information in real time, and collect the acceleration change curve in the braking process, such as Figure 1b Among them, the straight line is the brake signal sent by the system, and the curve is the actual acceleration change curve of the vehicle detected during braking. In each braking, the braking demand amount in the brake signal sent by the system, the new energy automatic driving vehicle will continuously send a constant brake deceleration signal during braking, the brake structure controlled by the brake system outputs a constant force acting on the brake pad, and the wear amount of the brake pad depends on the size of the acting force. The acting force applied on the braking structure is controlled by the brake signal sent by the system, that is, it depends on the size of the demand deceleration sent by the system.

[0059] Compared with the early warning scheme considering only the "static life" of the brake system, that is, only the performance early warning can be made according to the expected service life of the brake components, the dynamic and adaptive performance early warning cannot be achieved, and the brake usage cannot be monitored in real time, and the brake performance deficiency caused by some emergency and non-standard braking process cannot be early warned, for example, the braking performance requirement is increased during emergency braking, and the brake system triggered by the normal braking demand may not be sufficient at this time, and for example, high-frequency braking can cause rapid decline in braking performance, and the braking performance deficiency in this case cannot be monitored.

[0060] In the embodiment of the application, emergency braking performance early warning, high-frequency braking leading to braking performance decline early warning and brake wear total amount early warning are achieved. Through the combination of vehicle monitoring means and data platform calculation, the braking performance change condition is analyzed in real time, the braking performance state is dynamically analyzed and judged according to different braking demands of the vehicle, the cumbersome operation of manual detection of the braking system condition is reduced, the reaction is more rapid, the judgment basis is more accurate, and the efficient and safe operation of the autonomous vehicle is ensured.

[0061] The following is further described:

[0062] Referring to Figure 2 , a step flowchart of a brake performance early warning method provided by an embodiment of the application is shown, which can specifically include the following steps:

[0063] Step 201, acquiring driving data collected during braking of the vehicle in the process of autonomous driving of the vehicle.

[0064] In the process of autonomous driving, the vehicle determines whether braking is needed according to the actual driving condition, and sends a braking signal to the braking system when it is determined that braking is needed.

[0065] In the process of braking, the driving data of the vehicle can be collected, which can be collected by a braking signal monitoring system and an inertial navigation unit, and can include the acceleration, speed, driving distance and other driving data of the vehicle, but does not include the monitoring data of the brake pad thickness.

[0066] In the embodiment of the application, the driving data collected during braking is used to judge the subsequent braking performance, without relying on the detection of the brake pad, on the one hand, it can adapt to brake modules of different vehicle models, different structures and different materials, and on the other hand, it can warn the whole process of braking performance change without reaching the set thickness threshold, and has high sensitivity.

[0067] Step 202, determining the current braking scene, and judging whether the driving data triggers the early warning condition for the braking performance according to the current braking scene.

[0068] For some special scenarios, the requirement for braking performance is higher than the general requirement, such as the requirement for brake performance is higher than the general braking during emergency braking, the current braking scenario can be determined, whether the driving data triggers the warning condition for the braking performance is judged according to the current braking scenario, and then different warning strategies are adopted according to the braking scenario to adapt to the situation beyond the general braking.

[0069] In an embodiment of the present application, whether the driving data triggers the warning condition for the braking performance can be determined according to the current braking scenario, which can include:

[0070] In the case of a specified braking scenario, position data collected during automatic driving of the vehicle is obtained, and whether the driving data triggers the warning condition for the braking performance is determined in combination with the position data.

[0071] As an example, the specified braking scenario can include an emergency braking scenario and a high-frequency braking scenario.

[0072] In actual application, the vehicle can send its position data during braking to the data platform, and in the case of a specified braking scenario, the data platform determines whether the driving data triggers the warning condition for the braking performance in combination with the position data.

[0073] Step 203, in the case that the vehicle triggers the warning condition for the braking performance, a first warning message for the braking performance is generated.

[0074] In the case that the vehicle does not trigger the warning condition for the braking performance, the subsequent warning process can not be performed, and in the case that the vehicle triggers the warning condition for the braking performance, a first warning message for the braking performance is generated.

[0075] In an embodiment of the present application, by obtaining driving data collected during braking in the process of automatic driving of the vehicle, the current braking scenario is determined, whether the driving data triggers the warning condition for the braking performance is determined according to the current braking scenario, and in the case that the vehicle triggers the warning condition for the braking performance, a first warning message for the braking performance is generated, which realizes the warning of the braking performance according to the driving data of the vehicle braking. Since it does not depend on the monitoring of the thickness of the brake pad, on the one hand, it can adapt to different vehicle models, different structures, and different materials of the brake module, and on the other hand, it does not need to reach the set thickness threshold, and can warn the whole process of the change of the braking performance, with high sensitivity. Moreover, by adopting different warning strategies according to the braking scenario, it can adapt to the situation beyond the general braking.

[0076] Reference Figure 3a, shows a step flow chart of another brake performance early warning method provided by an embodiment of the present application, and can specifically include the following steps:

[0077] Step 301, obtaining driving data collected when braking in the process of automatic driving of the vehicle.

[0078] Step 302, determining the current braking scene.

[0079] Step 303, in the case of the current braking scene being an emergency braking scene, obtaining position data collected in the process of automatic driving of the vehicle.

[0080] When the brake signal emitted by the vehicle is monitored as full (100%) brake force output, it is judged that this is an emergency braking scene, and the brake performance judgment in the system emergency braking scene is activated.

[0081] Step 304, judging whether the current road condition is a non-specified road condition according to the position data.

[0082] In actual application, the data platform is provided with a road condition discrimination system, which can determine the current road condition according to the position information, and further judge whether the current road condition is a non-specified road condition. The specified road condition is the road condition with poor road surface condition, and the average brake energy efficiency of the braking behavior occurring here is low, which should not be used as the basis for performance judgment and should not be subjected to subsequent brake performance judgment.

[0083] On the one hand, the data platform has pre-recorded road classification information, which can be combined with the road classification information to judge whether it is a non-specified road condition. The state uses the characteristics of the road mainly as urban roads, highways, factory and mine roads, forest area roads and rural roads, and has specific and detailed classification for urban roads and highways. The urban road is divided into four levels of expressway, main road, secondary road and branch road; the highway is divided into five levels, which are respectively expressway, first-class highway, second-class highway, third-class highway and fourth-class highway. The specified road condition can be low-grade urban road and highway, factory and mine road, forest area road and rural road, which has poor road surface condition and low average brake energy efficiency of braking behavior occurring here.

[0084] On the other hand, the data platform contains weather information, which can be combined with the weather information to judge whether it is a non-specified road condition. When the vehicle is in a rain and snow weather area, the road condition is poor, and the brake performance of the vehicle will decrease significantly, which is a specified road condition.

[0085] Step 305, in the case of the current road condition being a non-specified road condition, determining the average deceleration of the vehicle according to the driving data.

[0086] In emergency braking scenarios, sufficient braking deceleration is required. The national standard has minimum requirements for the sufficient braking deceleration of vehicles, as shown in Table 1 below. When the vehicle's braking performance cannot meet the requirements, a warning signal can be issued.

[0087]

[0088] Table 1

[0089] In a specific implementation, the change curves of the vehicle's initial velocity, speed, and travel distance over time during the braking process can be recorded. After the braking process is completed, the actual average deceleration during this braking process can be calculated using the following formula:

[0090]

[0091] MFDD (Mean Fully Developed Deceleration) is the average deceleration in emergency braking scenarios, in meters per square second (m / s 2 ). V0 is the initial braking speed of the vehicle, in kilometers per hour (km\h). b =0.8V0, unit is kilometers per hour (km\h). V e =0.1V0, unit is kilometers per hour (km\h). S b The vehicle speed changes from V0 to V b The distance traveled between vehicles, in meters (m). e The vehicle speed changes from V0 to V e The distance traveled between the vehicles, in meters (m). 25.92 is the constant for calculating the average deceleration at full power.

[0092] After the average deceleration is calculated, the average deceleration can be sent to the data platform, or relevant driving data can be sent to the data platform for calculation.

[0093] Step 306 : When the average deceleration is less than the preset deceleration, it is determined that the vehicle triggers a warning condition for braking performance.

[0094] The preset deceleration may be a sufficient braking deceleration, as shown in Table 1 above.

[0095] If the average deceleration is less than the preset deceleration, meaning the average deceleration of this sufficient braking action does not meet the minimum requirement, the vehicle is determined to have triggered a warning condition for braking performance. If the average deceleration is greater than the preset deceleration, no further judgment is made.

[0096] Step 307, in the case that the vehicle triggers the pre-warning condition for braking performance, a first pre-warning message for braking performance is generated.

[0097] The following will be described in combination with Figure 3b The embodiments of the present application are exemplarily illustrated as follows:

[0098] For the vehicle end:

[0099] 1. Emergency braking behavior triggering system;

[0100] 2. Vehicle monitoring system collects data;

[0101] 3. Vehicle monitoring data (i.e. driving data) and position information (i.e. location data) are uploaded.

[0102] For the data platform end:

[0103] 1. Determine whether the road condition information meets the condition (i.e. determine whether the current road condition is a non-designated road condition);

[0104] 2. In the case that the road condition information does not meet the condition, the pre-warning is directly terminated;

[0105] 3. In the case that the road condition information meets the condition, the average braking deceleration is calculated, and it is determined whether the average deceleration meets the standard (i.e. it is determined whether the average deceleration is less than the preset deceleration);

[0106] 4. In the case that the average deceleration meets the standard (i.e. the average deceleration is greater than or equal to the preset deceleration), the pre-warning is directly terminated, and in the case that the average deceleration does not meet the standard (i.e. the average deceleration is less than the preset deceleration), a braking performance pre-warning is issued.

[0107] Referring to Figure 4a , a step flowchart of another braking performance pre-warning method provided by an embodiment of the present application is shown, which can specifically include the following steps:

[0108] Step 401, driving data collected when braking in the process of automatic driving of the vehicle is acquired.

[0109] Step 402, the current braking scene is determined.

[0110] Step 403, in the case that the current braking scene is a high-frequency braking scene, position data collected in the process of automatic driving of the vehicle is acquired.

[0111] In practical applications, the strength of braking performance is not only related to the wear degree of brake pads, but also related to the temperature of brake discs. When the temperature of brake discs rises, the braking performance of the vehicle will decrease. During the same road driving process, the brake discs cannot be cooled in time due to high-frequency braking operation of the vehicle, the temperature of the brake discs will rise rapidly, and the braking performance will decrease to cause a safety hazard. When the number of braking signals issued by the vehicle within a certain time is greater than a preset braking number, the current braking scene is a high-frequency braking scene.

[0112] In step 404, the braking energy efficiency ratio is determined according to the driving data.

[0113] In a specific implementation, the braking energy efficiency ratio can be determined according to the ratio of the given deceleration to the actual feedback deceleration. The braking energy efficiency ratio P is obtained by collecting the braking expected deceleration issued by the system and the actual vehicle deceleration detected by the IMU in the braking time period of the vehicle, and the following formula can be used:

[0114]

[0115] wherein a t is the actual average vehicle deceleration detected by the IMU, a0 is the braking expected deceleration issued by the system, and P is the braking energy efficiency ratio.

[0116] In step 405, when the braking energy efficiency ratio is greater than or equal to a preset energy efficiency ratio, the remaining braking road length is determined according to the position data.

[0117] In practical applications, the closer the braking energy efficiency ratio is to 1, the better the braking performance is, and the closer the braking requirement issued by the system is to the actual braking effect. When the braking energy efficiency ratio is too small, the braking performance is obviously degraded.

[0118] When the braking energy efficiency ratio is greater than or equal to the preset energy efficiency ratio, the vehicle will upload its own position to the data processing platform, and the remaining braking road length of the vehicle in the path planning is obtained according to the navigation route information and map information collected by the data platform.

[0119] In step 406, when the braking energy efficiency ratio cannot complete the braking of the remaining braking road length, it is determined that the vehicle triggers the warning condition for the braking performance.

[0120] When the braking energy efficiency ratio cannot complete the braking of the remaining braking road length, it is determined that the vehicle triggers the warning condition for the braking performance. When the braking energy efficiency ratio can complete the braking of the remaining braking road length, it is determined that the vehicle does not trigger the warning condition for the braking performance.

[0121] In an embodiment of the present application, step 406 can further include:

[0122] According to the brake energy efficiency ratio, brake energy efficiency decay data is determined; and according to the brake energy efficiency decay data, whether the brake energy efficiency ratio can complete braking of the remaining brake distance is predicted.

[0123] In a specific implementation, brake energy efficiency decay data (i.e., a change curve of time and brake energy efficiency) can be generated according to brake energy efficiency ratios in multiple braking processes, and then it is predicted according to a model when brake performance will drop below a dangerous line, i.e., when the brake energy efficiency ratio cannot complete braking of the remaining brake distance, and thus the vehicle can be reminded to pay attention to brake use frequency and an estimated number of remaining brake uses can be given in combination with road information.

[0124] Step 407: In a case where the vehicle triggers a warning condition for brake performance, a first warning message for brake performance is generated.

[0125] In an embodiment of the present application, the method can further include: determining that the vehicle triggers the warning condition for brake performance in a case where the brake energy efficiency ratio is less than a preset energy efficiency ratio.

[0126] In a case where the brake energy efficiency ratio is less than the preset energy efficiency ratio, it is determined that the vehicle triggers the warning condition for brake performance, and thus a system warning signal can be triggered. Figure 4b By monitoring brake parameters and then calculating a brake energy efficiency ratio, it is determined whether the brake energy efficiency ratio is lower than a threshold value (i.e., a preset energy efficiency ratio), a brake warning is triggered in a case where the brake energy efficiency ratio is lower than the threshold value, and relevant parameters are recorded in a case where the brake energy efficiency ratio is not lower than the threshold value.

[0127] The present application is described below by way of example with reference to the accompanying drawings: Figure 4c An embodiment of the present application is described by way of example:

[0128] For a vehicle end:

[0129] 1. A high-frequency brake behavior triggers a system.

[0130] 2. A vehicle monitoring system collects data (i.e., driving data).

[0131] 3. Vehicle monitoring data and orientation data (i.e., position data) are uploaded to a cloud platform.

[0132] For a data platform end:

[0133] 1. A brake energy efficiency ratio is calculated.

[0134] 2. It is determined whether the brake energy efficiency ratio is too low (i.e., whether it is less than a preset energy efficiency ratio).

[0135] 3. In a case where the brake energy efficiency ratio is too low, a brake performance warning is directly issued.

[0136] 4. If the braking energy efficiency ratio is not too low, further generate the braking energy efficiency ratio and distance curve (i.e. braking energy efficiency decay data), and then determine whether the braking energy efficiency can complete the remaining road section (i.e. whether the braking energy efficiency ratio can complete the braking of the remaining braking distance);

[0137] 5. If the braking energy efficiency cannot complete the remaining road section, a braking performance warning is issued; if the braking energy efficiency can complete the remaining road section, no subsequent processing is performed.

[0138] Referring to Figure 5a , a step flow chart of another braking performance warning method provided by an embodiment of the present application is shown, which can specifically include the following steps:

[0139] Step 501: Obtain driving data collected when braking in the process of automatic driving of the vehicle.

[0140] Step 502: Determine the current braking scene, and determine whether the driving data triggers a warning condition for braking performance according to the current braking scene.

[0141] Step 503: In the case where the vehicle triggers the warning condition for braking performance, generate a first warning message for braking performance.

[0142] Step 504: Update the total amount of braking loss according to the driving data.

[0143] In actual application, in order to dynamically predict the brake pad wear life, the internal law between the brake pad wear amount and the driving mileage needs to be known, and these laws usually imply the braking habits of the vehicle, the road conditions where the vehicle often drives, and other information. In the traditional method, the relationship between the wear amount and the driving mileage can be studied by measuring the brake pad wear amount within a certain driving mileage. For this method, the selection of the wear mileage sample is an important problem. The base sample of the wear mileage must be relatively large, and the statistical law reflecting the true road proportion and change must be obtained to accurately describe various driving road conditions of the vehicle and the corresponding vehicle speed.

[0144] For an automatic driving vehicle, the running area is generally fixed, and the road condition changes little, so the braking wear condition has a certain statistical law, and the relationship between the wear condition and the driving time can be found through the braking information statistics of a certain number of driving miles. In the embodiment of the present application, the data statistical capability of the data platform and the characteristics that the running route of the automatic driving vehicle is repeated to generate a large amount of braking information of similar road conditions can be used to obtain a brake pad wear amount model, which is specifically as follows:

[0145] 1. The collected driving data can include the braking expected deceleration a, the braking initial speed V and the braking duration t issued by the automatic driving system.

[0146] 2. Analyzing braking condition parameters, establishing a brake wear model. The data platform counts braking information, finds out the mapping relationship between the three braking condition parameters of initial braking speed, system given deceleration and braking duration and brake pad wear, establishes a brake wear model, the model input is the expected deceleration a, initial braking speed V and braking duration t, and the output is the brake wear in this braking process. When braking, the initial speed of the vehicle is different, and the braking performance reflected by the braking system is different. Different initial speed V corresponds to different basic brake wear coefficient β, which can be calculated by the following formula:

[0147] β=f(V;w v ,b v )=w v V+b v

[0148] Among them, the weight w v and the bias b v are obtained by fitting a large number of braking data statistics from the data platform.

[0149] Because the size of the system given deceleration affects the force on the brake pad, the longer the braking duration, the greater the single braking wear, and finally the brake wear model function Loss is obtained:

[0150] Loss==F(a,t,β)=F(a,t,f(V;w v ,b v ))

[0151] During the operation of the autonomous vehicle, the data platform will periodically collect a large amount of braking condition parameter data, and continuously correct the brake wear model function to calculate more accurate brake wear total according to the brake wear model function.

[0152] In monitoring and recording a complete braking process, the system given deceleration, initial vehicle speed and braking duration are obtained, and then the three braking condition parameters are input into the brake wear model, and the brake wear in this braking process is calculated by the wear calculation function, and the brake wear data in the single braking process is uploaded to the data platform.

[0153] After receiving the single braking wear uploaded by the vehicle end, the data platform can find the corresponding historical total wear of the vehicle, and statistically generate the brake wear total of the vehicle at the present stage.

[0154] Of course, the brake wear in the single braking process can also be calculated by the data platform.

[0155] In step 505, if the total brake loss is greater than the preset loss amount, a second warning message for brake performance is generated.

[0156] In the case where the total brake loss is greater than the preset loss amount, a second warning message for brake performance can be generated, and in the case where the total brake loss is less than or equal to the preset loss amount, no subsequent operation is performed.

[0157] The following will be described in combination with Figure 5b The embodiments of the present application are exemplarily described as follows:

[0158] For the vehicle end:

[0159] 1. A brake behavior triggering system;

[0160] 2. A vehicle monitoring system collects data (i.e., driving data);

[0161] 3. The vehicle monitoring data is uploaded to a cloud platform.

[0162] For the data platform end:

[0163] 1. Calculate the brake loss amount this time;

[0164] 2. Calculate the total brake loss amount;

[0165] 3. Determine whether the total brake loss amount exceeds the threshold value (i.e., whether the total brake loss amount is greater than the preset loss amount);

[0166] 4. In the case where the total brake loss amount exceeds the threshold value (i.e., the total brake loss amount is greater than the preset loss amount), a brake performance warning is issued, and in the case where the total brake loss amount does not exceed the threshold value (i.e., the total brake loss amount is less than or equal to the preset loss amount), the new total brake loss amount is updated and recorded.

[0167] It should be noted that, for the method embodiments, in order to simply describe, they are all described as a series of action combinations, but those skilled in the art should know that the embodiments of the present application are not limited by the action order described, because according to the embodiments of the present application, certain steps can be performed in other order or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification all belong to preferred embodiments, and the actions involved are not necessarily necessary for the embodiments of the present application.

[0168] Referring to Figure 6 , a structure schematic diagram of a brake performance warning device provided by an embodiment of the present application is shown, which can specifically include the following modules:

[0169] The driving data acquisition module 601 is used to acquire driving data collected when braking during automatic driving of the vehicle.

[0170] The early warning condition triggering judgment module 602 is configured to determine a current braking scene, and determine whether the driving data triggers the early warning condition for the braking performance according to the current braking scene.

[0171] The first early warning message generation module 603 is configured to generate the first early warning message for the braking performance in the case that the vehicle triggers the early warning condition for the braking performance.

[0172] In an embodiment of the present application, the early warning condition triggering judgment module 602 comprises:

[0173] The position data acquisition sub-module is configured to acquire position data collected in the process of automatic driving of the vehicle in the case that the current braking scene is the specified braking scene.

[0174] The early warning condition judgment sub-module combined with the position data is configured to determine whether the driving data triggers the early warning condition for the braking performance in combination with the position data.

[0175] In an embodiment of the present application, the early warning condition judgment sub-module combined with the position data comprises:

[0176] The non-specified road condition judgment unit is configured to determine whether the current road condition is a non-specified road condition according to the position data in the case that the current braking scene is the emergency braking scene.

[0177] The average deceleration determination unit is configured to determine the average deceleration of the vehicle according to the driving data in the case that the current road condition is the non-specified road condition.

[0178] The early warning condition judgment unit according to the average deceleration is configured to determine that the vehicle triggers the early warning condition for the braking performance in the case that the average deceleration is less than a preset deceleration.

[0179] In an embodiment of the present application, the early warning condition judgment sub-module combined with the position data comprises:

[0180] The braking energy efficiency ratio determination unit is configured to determine the braking energy efficiency ratio according to the driving data in the case that the current braking scene is the high-frequency braking scene.

[0181] The remaining braking road length determination unit is configured to determine the remaining braking road length according to the position data in the case that the braking energy efficiency ratio is greater than or equal to a preset energy efficiency ratio.

[0182] The first early warning condition judgment unit according to the braking energy efficiency ratio is configured to determine that the vehicle triggers the early warning condition for the braking performance in the case that the braking energy efficiency ratio cannot complete braking of the remaining braking road length.

[0183] In an embodiment of the present application, further comprising:

[0184] The brake energy efficiency decay data determining module is configured to determine brake energy efficiency decay data according to the brake energy efficiency ratio.

[0185] The brake energy efficiency decay data predicting module is configured to predict whether the brake energy efficiency ratio can complete the remaining brake distance according to the brake energy efficiency decay data.

[0186] In an embodiment of the present application, the device further comprises:

[0187] The second brake energy efficiency ratio judging early warning condition unit is configured to determine that the vehicle triggers the early warning condition for brake performance when the brake energy efficiency ratio is less than the preset energy efficiency ratio.

[0188] In an embodiment of the present application, the device further comprises:

[0189] The brake loss total amount updating module is configured to update the brake loss total amount according to the driving data.

[0190] The second early warning message generating module is configured to generate the second early warning message for brake performance when the brake loss total amount is greater than the preset loss total amount.

[0191] In an embodiment of the present application, by acquiring the driving data collected when braking in the process of automatic driving of the vehicle, the current braking scene is determined, and whether the driving data triggers the early warning condition for brake performance is judged according to the current braking scene. When the vehicle triggers the early warning condition for brake performance, the first early warning message for brake performance is generated, so as to realize the early warning of brake performance according to the driving data of the vehicle. Since it does not depend on the monitoring of the thickness of the brake pad, on the one hand, it can adapt to brake modules of different vehicle models, different structures and different materials, and on the other hand, it does not need to reach the set thickness threshold, and can early warn the whole process of brake performance change with high sensitivity. Moreover, by using different early warning strategies according to the braking scene, it can adapt to situations beyond normal braking.

[0192] An embodiment of the present application further provides an electronic device, which can include a processor, a memory, and a computer program stored on the memory and capable of running on the processor. When the computer program is executed by the processor, the brake performance early warning method is realized.

[0193] An embodiment of the present application further provides a computer readable storage medium, which stores a computer program. When the computer program is executed by the processor, the brake performance early warning method is realized.

[0194] For the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the related parts refer to the part of the method embodiment.

[0195] The various embodiments in the specification are described in progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between the embodiments can be mutually referred to.

[0196] Those skilled in the art will understand that the embodiments of the present application can be provided as methods, apparatuses, or computer program products. Therefore, the embodiments of the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the embodiments of the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage, etc.) containing computer-usable program code.

[0197] The embodiments of the present application are described with reference to flowcharts and / or block diagrams of the method, terminal device (system), and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device produce the apparatus for implementing the functions specified in one or more flows in the flowcharts and / or one or more blocks in the block diagrams.

[0198] These computer program instructions can also be stored in a computer-readable storage medium that can direct the computer or other programmable data processing terminal device to work in a specific manner, so that the instructions stored in the computer-readable storage medium produce a product including instruction apparatus, which implements the functions specified in one or more flows in the flowcharts and / or one or more blocks in the block diagrams.

[0199] These computer program instructions can also be loaded into a computer or other programmable data processing terminal device, so that a series of operation steps are performed on the computer or other programmable terminal device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable terminal device provide steps for implementing the functions specified in one or more flows in the flowcharts and / or one or more blocks in the block diagrams.

[0200] Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to the embodiments once they understand the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0201] Finally, it needs to be pointed out that in this document, relational terms such as first and second and the like can only be used to distinguish one entity or action from another entity or action, without necessarily requiring or implying that there is any such actual relationship or order between these entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, so that a process, method, article, or terminal device including a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or terminal device. Without more limitations, an element defined by the statement "comprising a" does not exclude the existence of additional identical elements in the process, method, article, or terminal device including the above element.

[0202] The above provides a detailed description of the method and device for early warning of braking performance. The principles and implementation modes of the present application are described by using specific examples. The above description of the embodiments is only used to help understand the method and core idea of the present application. Meanwhile, for those skilled in the art, the specific implementation modes and application ranges can be changed according to the idea of the present application. In summary, the content of the specification should not be understood as a limitation of the present application.

Claims

1. A method of warning of braking performance, characterized in that, The method comprises: acquiring driving data collected when braking in the process of automatic driving of a vehicle, the driving data comprising acceleration, vehicle speed, driving distance, braking expected deceleration, braking initial speed, braking duration of the vehicle; determining a current braking scenario, and judging whether the driving data triggers a warning condition for braking performance according to the current braking scenario; generating a first warning message for braking performance in the case that the vehicle triggers the warning condition for braking performance; updating a total braking loss amount according to the driving data, the total braking loss amount being calculated by a braking loss amount model to calculate a single braking loss amount and be updated based on the braking expected deceleration, the braking initial speed and the braking duration; generating a second warning message for braking performance in the case that the total braking loss amount is greater than a preset total loss amount.

2. The method of claim 1, wherein, The judging whether the driving data triggers the warning condition for braking performance according to the current braking scenario comprises: acquiring position data collected in the process of automatic driving of the vehicle in the case that the current braking scenario is a specified braking scenario; judging whether the driving data triggers the warning condition for braking performance in combination with the position data.

3. The method of claim 2, wherein, The judging whether the driving data triggers the warning condition for braking performance in combination with the position data comprises: judging whether a current road condition is a non-specified road condition according to the position data in the case that the current braking scenario is an emergency braking scenario; determining an average deceleration of the vehicle according to the driving data in the case that the current road condition is a non-specified road condition; determining that the vehicle triggers the warning condition for braking performance in the case that the average deceleration is less than a preset deceleration.

4. The method of claim 2, wherein, The judging whether the driving data triggers the warning condition for braking performance in combination with the position data comprises: determining a braking energy efficiency ratio according to the driving data in the case that the current braking scenario is a high-frequency braking scenario; determining a remaining braking road length according to the position data in the case that the braking energy efficiency ratio is greater than or equal to a preset energy efficiency ratio; determining that the vehicle triggers the warning condition for braking performance in the case that the braking energy efficiency ratio cannot complete braking of the remaining braking road length.

5. The method of claim 4, wherein, Before determining that the vehicle triggers the warning condition for braking performance in the case that the braking energy efficiency ratio cannot complete braking of the remaining braking road length, the method further comprises: determining braking energy efficiency attenuation data according to the braking energy efficiency ratio; predicting whether the braking energy efficiency ratio can complete braking of the remaining braking road length according to the braking energy efficiency attenuation data.

6. The method according to claim 4 or 5, characterized in that, The method further comprises: determining that the vehicle triggers the warning condition for braking performance in the case that the braking energy efficiency ratio is less than the preset energy efficiency ratio.

7. A brake performance early warning device characterized by comprising: The device comprises: a driving data acquisition module configured to acquire driving data collected when braking in the process of automatic driving of a vehicle, the driving data comprising acceleration, vehicle speed, driving distance, braking expected deceleration, braking initial speed, braking duration of the vehicle; An early warning condition triggering judgment module is configured to determine a current braking scenario, and determine whether the driving data triggers an early warning condition for braking performance according to the current braking scenario; A first early warning message generation module is configured to generate a first early warning message for braking performance when the vehicle triggers the early warning condition for braking performance; A braking loss total amount updating module is configured to update the braking loss total amount according to the driving data, and the braking loss total amount is calculated by a braking loss amount model based on the braking expected deceleration, the braking initial speed and the braking duration to update a single braking loss amount; A second early warning message generation module is configured to generate a second early warning message for braking performance when the braking loss total amount is greater than a preset loss total amount.

8. An electronic device, comprising: A computer program is stored on a memory and can be run on a processor, and the computer program is executed by the processor to implement the early warning method for braking performance according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, A computer program is stored on a computer readable storage medium and is executed by a processor to implement the early warning method for braking performance according to any one of claims 1 to 6.

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