Method, system and equipment for evaluating driving safety of double-trailer train

Abstract

The invention discloses a double-trailer train driving safety assessment method, system and device. The method comprises the steps of obtaining downhill curve road section data; determining the maximum transverse adhesion coefficient of the axles of the double-trailer train according to the downhill curve road section data; according to the maximum transverse adhesion coefficient of the axle and a preset road adhesion coefficient, calculating a sideslip evaluation index of the double-trailer train; the transverse load transfer ratio of the double-trailer train is determined according to the downhill curve road section data, and a rollover evaluation index of the double-trailer train is calculated according to the transverse load transfer ratio and a preset stability threshold value; determining a first hinge angle between the tractor and the semitrailers and a second hinge angle between the semitrailers according to the downhill curve road section data, and calculating according to the first hinge angle and the second hinge angle to obtain a folding evaluation index of the double-trailer combination vehicle; and determining the out-of-control probability of the double-trailer train according to the sideslip evaluation index data, the rollover evaluation index and the folding evaluation index so as to guarantee the driving safety.

Description

Technical Field

[0001] The present application relates to the field of traffic engineering, and specifically to a method, system and equipment for evaluating the driving safety of a double-trailer train. Background Art

[0002] As a flexible mode of freight transport, automobile trains are widely adopted around the world due to their high carrying capacity, cost-effectiveness, and high transportation efficiency. To improve freight transportation efficiency, semi-trailers and double-trailers have also emerged. Currently, some cities and counties in China have launched pilot operations of double-trailer automobile trains, using a fixed route. Although double-trailer automobile trains are more efficient in transporting freight, due to their structural characteristics such as long body, multiple articulation points, large load capacity, and high center of gravity, they are prone to instability risks such as rollover and skidding of the entire vehicle, and folding between vehicle units, especially on downhill curves. When the pilot route of a double-trailer automobile train involves downhill curves, the potential risks need to be studied and assessed in advance. However, the existing technology lacks a safety assessment plan for the pilot operation of double-trailer automobile trains, and the transportation department is unable to reasonably plan the drivable sections of the double-trailer automobile train based on the safety assessment. Summary of the Invention

[0003] In view of this, the embodiments of the present application hope to provide a double-trailer train driving safety assessment system, method and equipment to at least solve the above-mentioned technical problems.

[0004] To achieve the above objectives, the technical solution of this application is implemented as follows:

[0005] According to one aspect of an embodiment of the present application, a method for evaluating the driving safety of a double-trailer train is provided, the method comprising:

[0006] Get downhill curve road section data;

[0007] Determining the maximum lateral adhesion coefficient of the axles of the double-trailer train based on the downhill curved road section data;

[0008] Calculating a sideslip evaluation index of the double-trailer train based on the maximum lateral adhesion coefficient of the axle and a preset road adhesion coefficient;

[0009] Determining a lateral load transfer ratio of the double-trailer car train based on the downhill curved road section data, and calculating a rollover evaluation index of the double-trailer car train based on the lateral load transfer ratio and a preset stability threshold;

[0010] Determining a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers based on the downhill curved road section data, and calculating a folding evaluation index of the double-trailer vehicle train based on the first articulation angle and the second articulation angle;

[0011] The out-of-control probability of the double-trailer car train is determined based on the sideslip evaluation index data, the rollover evaluation index and the folding evaluation index.

[0012] Optionally, the downhill curved road section data includes: road surface circular curve radius, transverse slope data and longitudinal slope data.

[0013] Optionally, determining the maximum lateral adhesion coefficient of the axles of the double-trailer train based on the downhill curved road section data includes:

[0014] Determining the lateral force and vertical force exerted on the tires of each axle of the double-trailer vehicle train based on the downhill curved road section data;

[0015] The ratio of the lateral force to the vertical force exerted on the tires of each axle is determined, and the maximum value of the absolute value of the ratio is determined as the maximum lateral adhesion coefficient of the axle of the double-trailer car train.

[0016] Optionally, the lateral force and vertical force exerted on the tires of each axle in the double-trailer car train are positively correlated with the driving speed; the driving speed of the double-trailer car train and the preset road adhesion coefficient are random variables; wherein the preset road adhesion coefficient is in a normal distribution range determined based on different road conditions.

[0017] Optionally, before the step of determining the maximum lateral adhesion coefficient of the axles of the double-trailer vehicle train based on the downhill curved road section data, the method further includes:

[0018] Randomly assign values ​​to the vehicle mass, driving speed and the preset road adhesion coefficient of the double-trailer vehicle train.

[0019] Optionally, determining the lateral load transfer ratio of the double-trailer train based on the downhill curved road section data includes:

[0020] Determining vertical load values ​​on the left and right tires of the double-trailer train respectively based on the downhill curved road section data;

[0021] The ratio of the difference between the vertical load values ​​on the left and right tires to the total vertical load values ​​on the left and right tires is determined as the lateral load transfer ratio of the double-trailer train.

[0022] Optionally, the calculating of the folding evaluation index of the double-trailer vehicle train according to the first articulation angle and the second articulation angle includes:

[0023] determining a maximum value from the first articulation angle and the second articulation angle as a target articulation angle;

[0024] A folding evaluation index of the double-trailer car train is calculated based on the target articulation angle and a preset safety threshold.

[0025] Optionally, determining the first articulation angle between the tractor and the semi-trailer, and the second articulation angle between the semi-trailers according to the downhill curved road section data includes:

[0026] A first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers are determined according to the downhill curved road section data through a preset dynamic simulation model.

[0027] According to a second aspect of the present application, a double-trailer train driving safety assessment system is provided, the system comprising:

[0028] A data acquisition module is used to acquire downhill curved road section data;

[0029] a sideslip evaluation index determination module, configured to determine a maximum lateral adhesion coefficient of an axle of a double-trailer vehicle train based on the downhill curved road section data; and calculate a sideslip evaluation index of the double-trailer vehicle train based on the maximum lateral adhesion coefficient of the axle and a preset road adhesion coefficient;

[0030] a rollover evaluation index determination module, configured to determine a lateral load transfer ratio of the double-trailer car train based on the downhill curved road section data, and calculate a rollover evaluation index of the double-trailer car train based on the lateral load transfer ratio and a preset stability threshold;

[0031] a folding evaluation index determination module, configured to determine a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers based on the downhill curved road section data, and calculate a folding evaluation index of the double-trailer vehicle train based on the first articulation angle and the second articulation angle;

[0032] The out-of-control probability determination module is used to determine the out-of-control probability of the double-trailer car train based on the sideslip evaluation index data, the rollover evaluation index and the folding evaluation index.

[0033] According to a third aspect of the present application, a double-trailer train driving safety assessment device is provided, the device comprising:

[0034] at least one processor; and

[0035] a memory communicatively coupled to the at least one processor; wherein:

[0036] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any of the above-mentioned methods for evaluating the driving safety of a double-trailer train.

[0037] The present application provides a method, system, and device for evaluating the driving safety of a double-trailer train, which analyzes the side slip, rollover, and folding conditions of the vehicle to implement a solution for evaluating the driving safety of a double-trailer train on a downhill curved road section. Specifically, by collecting data on the downhill curved road section, the double-trailer train's side slip evaluation index, rollover evaluation index, and folding evaluation index are determined based on the downhill curved road section data. The double-trailer train's probability of loss of control is then determined based on the side slip evaluation index, rollover evaluation index, and folding evaluation index. The failure modes of side slip, rollover, and folding are independent of each other. When any of these failure modes occurs, the double-trailer train is deemed to be in a failed state. Based on the safety and reliability data obtained from the analysis, the road sections where the double-trailer train can travel can be rationally planned, thereby ensuring the safety of cargo transported by the double-trailer train. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the steps of the double-trailer train driving safety assessment method in this application;

[0039] Figure 2 Schematic diagram of the structure of the double-trailer train driving safety assessment system in this application;

[0040] Figure 3 This is a schematic diagram of the structural composition of the double-trailer train driving safety assessment equipment in this application. DETAILED DESCRIPTION

[0041] The technical solution of the present application is further elaborated in detail below with reference to the accompanying drawings and specific embodiments.

[0042] The various specific technical features in the various embodiments described in the specific implementation methods can be combined in various ways without contradiction. For example, different implementation methods can be formed by combining different specific technical features. In order to avoid unnecessary repetition, the various possible combinations of the specific technical features in this application will not be described separately.

[0043] It should be noted that the terms "first, second, and third" in the embodiments of the present application are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It is understood that the terms "first, second, and third" can be interchanged to represent a specific order or precedence where permitted. It should be understood that the objects distinguished by "first, second, and third" can be interchanged where appropriate, such that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0044] To facilitate those skilled in the art to understand the technical solutions provided in the embodiments of the present application, the following describes the relevant technologies:

[0045] As a flexible mode of freight transport, car trains are widely adopted worldwide due to their high carrying capacity, cost-effectiveness, and high transport efficiency. To further enhance freight transport efficiency, the use of semi-trailers is also common, but the use of double-trailer car trains is less common. In September 2012, the Ministry of Industry and Information Technology (MIIT) brought full-length trailers under regulatory control and issued a related notice, which has increased the opportunities for full-length trailers to operate on highways. In Europe, extensive practice and research have led to the development of three efficient and safe trailer combinations: Type A, Type B, and Type C. Furthermore, many European countries are conducting performance tests on extra-long trailers exceeding 30 meters in length and weighing 70 tons, and these vehicles are now legally permitted on public roads.

[0046] At present, some cities and counties in China have launched pilot operations of double-trailer car trains, using a fixed route. However, due to the structural characteristics of double-trailer car trains, such as long body, multiple articulation points, large load capacity, and high center of mass, they are prone to instability risks such as rollover and skidding of the entire vehicle, and folding between vehicle units, especially on downhill curved sections. When the pilot routes of double-trailer car trains involve downhill curved sections, it is necessary to study and evaluate the possible risks in advance. Therefore, based on the combination of the structure and performance parameters of the double-trailer car train body and the basic data of the downhill curved sections of the pilot operation, a double-trailer car train dynamic model is used to propose a safety and reliability evaluation method for double-trailer car train operation on downhill curved sections. This method is of great significance to the scientific determination of the pilot routes of double-trailer car trains.

[0047] The inventors found that the existing technology rarely considers risk assessment in the pilot operation of double-trailer car trains. Downhill curve data (such as the circular curve radius of the road, the road adhesion coefficient, the transverse slope, the longitudinal slope, etc.) are not used to assess the operation risk of double-trailer car trains, and the safety and reliability of the operation of double-trailer car trains on downhill curve sections are not studied.

[0048] To this end, an embodiment of the present application provides a technical solution for a method for evaluating the driving safety of a double-trailer vehicle train. In this technical solution, downhill curved road section data is obtained; the maximum lateral adhesion coefficient of the axle of the double-trailer vehicle train is determined based on the downhill curved road section data; a sideslip evaluation index of the double-trailer vehicle train is calculated based on the maximum lateral adhesion coefficient of the axle and a preset road adhesion coefficient; a lateral load transfer ratio of the double-trailer vehicle train is determined based on the downhill curved road section data, and a rollover evaluation index of the double-trailer vehicle train is calculated based on the lateral load transfer ratio and a preset stability threshold; a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers are determined based on the downhill curved road section data, and a folding evaluation index of the double-trailer vehicle train is calculated based on the first and second articulation angles; and a loss of control probability of the double-trailer vehicle train is determined based on the sideslip evaluation index data, the rollover evaluation index, and the folding evaluation index. By collecting data on downhill curved sections, the sideslip evaluation index, rollover evaluation index and folding evaluation index of the double-trailer car train are determined based on the downhill curved section data, and then the loss of control probability of the double-trailer car train is determined based on the sideslip evaluation index, rollover evaluation index and folding evaluation index. The vehicle loss of control in the sideslip, rollover and folding modes are independent of each other. When any failure occurs, it can be determined that the double-trailer car train is in a loss-of-control state. Therefore, based on the safety and reliability data obtained by analysis, the road sections where the double-trailer car train can travel can be reasonably planned to ensure the safety of the double-trailer car train.

[0049] The technical solutions of the present application are described below through a number of embodiments. It should be noted that these embodiments can be implemented in a variety of different forms and should not be construed as being limited to the embodiments described herein.

[0050] Example 1

[0051] Figure 1 This is a schematic diagram of the process implementation of the double-trailer train driving safety assessment method in this application, as shown in Figure 1 As shown, the method includes steps S101-S106, wherein,

[0052] Step S101, acquiring downhill curved road section data;

[0053] Since different road surface circular curve radii, transverse slopes, and longitudinal slopes will affect the driving stability of the double-trailer train, these data are collected in this embodiment to evaluate the operating risk of the double-trailer train.

[0054] Specifically, any vehicle is used, and equipment such as VBOX, a high-precision positioning device, and road transverse and longitudinal slope collection sensors are installed on the vehicle. By piloting the downhill curved sections of the road, the downhill curved section data collected by the above equipment can be obtained for subsequent risk assessment.

[0055] The downhill curve road section data includes: road surface circular curve radius, transverse slope data and longitudinal slope data.

[0056] Step S102, determining the maximum lateral adhesion coefficient of the axles of the double-trailer train based on the downhill curved road section data;

[0057] In this embodiment, the double-trailer train includes nine axles, and the maximum lateral adhesion coefficient f of the axles is selected. D As an evaluation index for vehicle sideslip, this index can comprehensively reflect the force conditions on each axle of the vehicle under various transient responses during vehicle driving. It is defined as the maximum value of the absolute value of the ratio of the lateral force to the vertical force on the tires of each axle in a nine-axle double-trailer train. The expression is as follows:

[0058]

[0059] In the above expression, n=1, 2, 3…9, representing the axis; t is time.

[0060] Among them: F yLno (t) and F yLni (t) are the lateral forces acting on the outer and inner tires on the left side of the nth axle at time t; F yRno (t) and F yRni (t) are the lateral forces acting on the outer and inner tires on the right side of the nth axle at time t; F zLno (t) and F zLni (t) are the vertical forces acting on the outer and inner tires on the left side of the nth axle at time t; F zRno (t) and F zRni (t) are the vertical forces acting on the outer and inner tires on the right side of the nth axle at time t.

[0061] Step S103, calculating a sideslip evaluation index of the double-trailer train based on the maximum lateral adhesion coefficient of the axle and a preset road adhesion coefficient;

[0062] The road adhesion coefficient is the ratio of adhesion to wheel normal pressure (perpendicular to the road surface) and can be considered the static friction coefficient between the tire and the road surface. In rough calculations, the road adhesion coefficient can be considered the static friction coefficient between the tire and the road surface. The road adhesion coefficient directly reflects the maximum adhesion a tire can provide under different road conditions and is crucial to vehicle driving stability and safety.

[0063] In this embodiment, the preset road adhesion coefficient is a safety threshold for the maximum lateral adhesion coefficient of the axle. This preset road adhesion coefficient falls within a normally distributed range determined based on different road conditions. Specifically, different weather conditions, such as sunny days, rainy days, snowy days, icy conditions, and sandstorms, have different effects on the road adhesion coefficient. Through extensive data analysis, the possible range of the road adhesion coefficient has been determined, and the preset road adhesion coefficient of this embodiment is set within this range. As an example, the preset road adhesion coefficient may fall within a normally distributed range with a mean of 0.6 and a variance of 0.1.

[0064] In this embodiment, when the maximum lateral adhesion coefficient of the axle is f D Exceeds the preset road adhesion coefficient f S When f S >f S Therefore, the side slip failure model of the double-trailer train is established as follows:

[0065] Z1=f S -f D

[0066] By substituting the calculated maximum lateral adhesion coefficient of the axle and the preset road adhesion coefficient into the above-mentioned sideslip failure model, the sideslip evaluation index Z1 of the double-trailer train can be calculated.

[0067] Step S104, determining a lateral load transfer ratio of the double-trailer train based on the downhill curved road section data, and calculating a rollover evaluation index of the double-trailer train based on the lateral load transfer ratio and a preset stability threshold;

[0068] Rollover is a common type of accident for heavy trucks, and double-trailer trucks have the characteristics of a high center of mass and a large load capacity, so the probability of rollover is much higher than that of other models. TR As an evaluation index of vehicle rollover, it can accurately reflect the tendency of vertical force transfer on the tires when the vehicle turns. It is defined as: at the tth moment, the ratio of the difference between the vertical loads on the left and right tires to the total vertical loads on the left and right tires. The expression is as follows:

[0069]

[0070] In the above expression, n=1, 2, 3…9, representing the axis; t is time.

[0071] Among them, L TR (t) is the lateral load transfer ratio at the tth moment in a simulation scenario with a total time of T. zLno (t) and F zLni(t) are the vertical forces acting on the outer and inner tires on the left side of the nth axle at time t; F zCno (t) and F zRni (t) are the vertical forces acting on the outer and inner tires on the right side of the nth axle at time t.

[0072] In this embodiment, the preset stability threshold is a pre-set safety threshold. When the vertical loads on the left and right wheels do not transfer laterally, L TR When one side of the wheel leaves the ground, the vertical load of the wheel on that side is completely transferred to the wheel on the other side, L TR is 1. Therefore L TR Safety threshold =1. Therefore, the rollover failure model of the semi-trailer train is established as:

[0073]

[0074] By substituting the calculated lateral load transfer ratio and the preset stability threshold of the double-trailer car train into the above-mentioned rollover failure model, the rollover evaluation index Z2 of the double-trailer car train can be calculated.

[0075] Step S105, determining a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers based on the downhill curved road section data, and calculating a folding evaluation index of the double-trailer vehicle train based on the first articulation angle and the second articulation angle;

[0076] Specifically, the preset dynamic simulation model can be used to determine the first articulation angle between the tractor and the semi-trailer, and the second articulation angle between the semi-trailers according to the downhill curve section data, and the folding evaluation index of the double-trailer vehicle train can be calculated based on the first articulation angle and the second articulation angle.

[0077] In a specific implementation, the preset dynamic simulation model can be a model constructed by TruckSim simulation software. A dynamic simulation model of a nine-axle double-trailer car train is constructed by using TruckSim simulation software. The simulation software adopts a characteristic-oriented parametric modeling method. By calibrating the vehicle model, constructing the road model and the driver control method, it derives the multi-rigid body system dynamic model and generates the corresponding calculation program in different simulation scenarios, which can output the vehicle's dynamic response in real time and accurately.

[0078] In this embodiment, the articulation angles θ1 and θ2 between the tractor-trailer-trailer are selected as evaluation indicators for vehicle folding. The safety threshold of the articulation angle θ 0 For example, θ 0 The angle is 10°, so the folding failure model of the double-trailer train is established as:

[0079] Z3=θ 0 -max(θ1,θ2)

[0080] After determining the first articulation angle θ1 between the tractor and the semi-trailer, and the second articulation angle θ2 between the semi-trailers through a preset dynamic simulation model, the folding evaluation index Z3 of the double-trailer train can be calculated by substituting θ1 and θ2 into the above-mentioned folding failure model.

[0081] Step S106: determining the out-of-control probability of the double-trailer train based on the sideslip evaluation index data, the rollover evaluation index, and the folding evaluation index.

[0082] In this embodiment, the functional function of system loss of control of the double-trailer train is determined by the three modes of sideslip, rollover, and folding. Assuming that these three failure modes are independent of each other, when any one failure occurs, it can be determined that the system is in a failed state. Therefore, the functional function of system failure can be considered as the series connection of the three failure modes of sideslip, rollover, and folding, and the output is the failure probability or safety reliability.

[0083] Specifically, the probability of a double-trailer train losing control satisfies the following expression:

[0084] Z=1-(1-Z1)*(1-Z2)*(1-Z3)

[0085] After the sideslip evaluation index Z1, rollover evaluation index Z2 and folding evaluation index Z3 of the double-trailer train are obtained through the calculation in the above steps, the out-of-control probability Z of the double-trailer train can be obtained by substituting the numerical values ​​into the above expressions for calculation.

[0086] In a preferred embodiment of the present application, determining the maximum lateral adhesion coefficient of the axles of the double-trailer vehicle train based on the downhill curved road section data includes:

[0087] The lateral force and vertical force acting on the tires of each axle in the double-trailer car train are determined based on the downhill curved road section data; the ratio of the lateral force to the vertical force acting on the tires of each axle is determined, and the maximum value of the absolute value of the ratio is determined as the maximum lateral adhesion coefficient of the axle of the double-trailer car train.

[0088] In this embodiment, the lateral force and vertical force acting on the tires of each axle of the double-trailer train are determined based on the downhill curved road section data; the ratio of the lateral force to the vertical force acting on the tires of each axle is further determined, and the maximum value of the absolute value of the ratio is determined as the maximum lateral adhesion coefficient of the axle of the double-trailer train.

[0089] Specifically, the expression of the maximum lateral adhesion coefficient is as follows:

[0090]

[0091] In the above expression, n=1, 2, 3…9, representing the axis; t is time.

[0092] Among them: F yLno (t) and F yLni (t) are the lateral forces acting on the outer and inner tires on the left side of the nth axle at time t; F yRno (t) and F yRni (t) are the lateral forces acting on the outer and inner tires on the right side of the nth axle at time t; F zLno (t) and F zLni (t) are the vertical forces acting on the outer and inner tires on the left side of the nth axle at time t; F zRno (t) and F zRni (t) are the vertical forces acting on the outer and inner tires on the right side of the nth axle at time t.

[0093] In a preferred embodiment of the present application, the lateral force and vertical force exerted on the tires of each axle in the double-trailer car train are positively correlated with the driving speed; the driving speed of the double-trailer car train and the preset road adhesion coefficient are random variables; wherein the preset road adhesion coefficient is in a normal distribution range determined based on different road conditions.

[0094] Specifically, let F be the centrifugal force on the vehicle; G be the gravity on the vehicle: F y is the total lateral force acting on the vehicle; F z is the total vertical force acting on the vehicle; F yLno (t) and F _Lnc (t) are the lateral forces acting on the outer and inner tires on the right side of the nth axle at time t; F yRno (t) and F yRni (t) are the lateral forces acting on the outer and inner tires on the right side of the nth axle at time t; F zLno (t) and F zLni (t) are the vertical forces acting on the outer and inner tires on the left side of the nth axle at time t; F zRno (t) and F zRni (t) are the vertical forces acting on the outer and inner tires on the right side of the nth axle at time t; α is the lateral slope angle, and θ is the longitudinal slope angle.

[0095] The centrifugal force F exerted on a vehicle when it passes through a curve with a radius of R satisfies the following expression:

[0096]

[0097] The total lateral force F acting on the vehicle y Satisfies the following expression:

[0098]

[0099] The total lateral force F exerted on the vehicle on a downhill curve with a lateral slope angle of α and a longitudinal slope angle of θ is y And it satisfies the following expression:

[0100]

[0101] Therefore, based on the above expressions, it can be seen that the lateral and vertical forces acting on the tires of each axle in a double-trailer train are positively correlated with the driving speed. In this embodiment, the driving speed of the double-trailer train and the preset road adhesion coefficient are random variables. The sampling frequency is determined and a series of random variables (including vehicle speed and road adhesion coefficient) are generated. Simulation is performed using TruckSim software, and the sample values ​​are output. This is used to calculate the failure probability of the double-trailer train under different random variables.

[0102] In a preferred embodiment of the present application, before the step of determining the maximum lateral adhesion coefficient of the axles of the double-trailer vehicle train based on the downhill curved road section data, the method further includes:

[0103] Randomly assign values ​​to the vehicle mass, driving speed and the preset road adhesion coefficient of the double-trailer vehicle train.

[0104] In this embodiment, the speed of the double-trailer train and the preset road adhesion coefficient are random variables. By determining the number of sampling times and generating a series of random variables (including vehicle speed and road adhesion coefficient), simulation is performed using TruckSim software to output sample values; in order to calculate the failure probability of the double-trailer train under different random variables.

[0105] Because excessive vehicle load increases the rollover moment experienced by the vehicle during steering, further affecting its stability, it is essential to implement reasonable weight limits on double-trailer trains. In this embodiment, the failure probability of a double-trailer train under different vehicle masses, speeds, and road adhesion coefficients is analyzed by randomly assigning values ​​to the vehicle mass, speed, and road adhesion coefficient.

[0106] In a preferred embodiment of the present application, determining the lateral load transfer ratio of the double-trailer vehicle train based on the downhill curved road section data includes:

[0107] Based on the downhill curved road section data, vertical load values ​​acting on the left and right tires of the double-trailer car train are respectively determined; and the ratio of the difference between the vertical load values ​​acting on the left and right tires to the sum of the vertical load values ​​acting on the left and right tires is determined as the lateral load transfer ratio of the double-trailer car train.

[0108] Specifically, the lateral load transfer ratio of the double-trailer train satisfies the following expression:

[0109]

[0110] In the above expression, n=1, 2, 3…9, representing the axis; t is time.

[0111] Among them, L TR (t) is the lateral load transfer ratio at the tth moment in a simulation scenario with a total time of T. zLno (t) and F zLni (t) are the vertical forces acting on the outer and inner tires on the left side of the nth axle at time t; F zCno (t) and F zRni (t) are the vertical forces acting on the right outer and inner tires of the nth axle at time t, respectively. The vertical load values ​​acting on the left and right tires of the double-trailer train are determined based on the downhill curve data. The ratio of the difference between the vertical load values ​​acting on the left and right tires to the sum of the vertical load values ​​acting on the left and right tires is determined as the lateral load transfer ratio of the double-trailer train.

[0112] In a preferred embodiment of the present application, the folding evaluation index of the double-trailer car train is calculated based on the first articulation angle and the second articulation angle, including:

[0113] A maximum value is determined from the first articulation angle and the second articulation angle as a target articulation angle; and a folding evaluation index of the double-trailer car train is calculated based on the target articulation angle and a preset safety threshold.

[0114] In this embodiment, the articulation angles θ1 and θ2 between the tractor-trailer-trailer are selected as evaluation indicators for vehicle folding. The safety threshold of the articulation angle θ 0 For example, θ 0 The angle is 10°, so the folding failure model of the double-trailer train is established as:

[0115] Z3=θ 0 -max(θ1,θ2)

[0116] After determining the first articulation angle θ1 between the tractor and the semi-trailer, and the second articulation angle θ2 between the semi-trailers through a preset dynamic simulation model, the folding evaluation index Z3 of the double-trailer train can be calculated by substituting θ1 and θ2 into the above-mentioned folding failure model.

[0117] In this embodiment, determining the first articulation angle between the tractor and the semi-trailer, and the second articulation angle between the semi-trailers according to the downhill curved road section data includes:

[0118] A first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers are determined according to the downhill curved road section data through a preset dynamic simulation model.

[0119] The pre-built dynamic simulation model can be a model built using TruckSim simulation software. This software was used to construct a dynamic simulation model of a nine-axle, double-trailer train. This simulation software uses a characteristic-oriented parametric modeling approach. By calibrating the vehicle model, constructing the road model, and analyzing the driver's control methods, it derives a multi-rigid-body system dynamic model and generates corresponding calculation programs in different simulation scenarios, enabling real-time and accurate output of the vehicle's dynamic response. During the simulation experiment, after the simulation model was constructed, data from a downhill curve section was input into the simulation model to calculate and output the first articulation angle between the tractor and semi-trailer, and the second articulation angle between the semi-trailers. This was used to calculate the folding failure index of the double-trailer train.

[0120] In this embodiment, by collecting data on downhill curved road sections, the sideslip evaluation index, rollover evaluation index and folding evaluation index of the double-trailer car train are determined based on the downhill curved road section data, and then the loss of control probability of the double-trailer car train is determined based on the sideslip evaluation index, rollover evaluation index and folding evaluation index. The vehicle loss of control in the sideslip, rollover and folding modes are independent of each other. When any one of the failures occurs, it can be determined that the double-trailer car train is in a loss of control state. Therefore, based on the safety and reliability data obtained by analysis, the road sections where the double-trailer car train can travel can be reasonably planned to ensure the safety of the double-trailer car train.

[0121] Example 2

[0122] Figure 2 The following is a schematic diagram of the structure of the double-trailer train driving safety assessment system in this application. The system can be divided into one or more program modules, one or more program modules are stored in a storage medium and executed by one or more processors to complete the embodiment of this application. The program module referred to in the embodiment of this application refers to a series of computer program instruction segments that can complete specific functions. The following description will specifically introduce the functions of each program module in this embodiment. Figure 2 As shown, the double-trailer train driving safety assessment system may include the following modules: a data acquisition module 201, a sideslip evaluation index determination module 202, a rollover evaluation index determination module 203, a folding evaluation index determination module 204, and a loss of control probability determination module 205, wherein:

[0123] The data acquisition module 201 is used to acquire downhill curved road section data;

[0124] The side slip evaluation index determination module 202 is configured to determine the maximum lateral adhesion coefficient of the axles of the double-trailer vehicle train based on the downhill curved road section data; and calculate the side slip evaluation index of the double-trailer vehicle train based on the maximum lateral adhesion coefficient of the axles and a preset road adhesion coefficient;

[0125] A rollover evaluation index determination module 203 is configured to determine a lateral load transfer ratio of the double-trailer vehicle train based on the downhill curved road section data, and calculate a rollover evaluation index of the double-trailer vehicle train based on the lateral load transfer ratio and a preset stability threshold;

[0126] a folding evaluation index determination module 204 for determining a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers based on the downhill curved road section data, and calculating a folding evaluation index of the double-trailer vehicle train based on the first articulation angle and the second articulation angle;

[0127] The out-of-control probability determination module 205 is used to determine the out-of-control probability of the double-trailer train based on the sideslip evaluation index data, the rollover evaluation index and the folding evaluation index.

[0128] In a preferred embodiment of the present application, the downhill curved road section data includes: road surface circular curve radius, transverse slope data and longitudinal slope data.

[0129] In a preferred embodiment of the present application, the sideslip evaluation index determination module 202 includes:

[0130] The maximum lateral adhesion coefficient determination submodule is used to determine the lateral force and vertical force exerted on the tires of each axle in the double-trailer car train based on the downhill curved road section data; determine the ratio of the lateral force to the vertical force exerted on the tires of each axle, and determine the maximum value of the absolute value of the ratio as the maximum lateral adhesion coefficient of the axle of the double-trailer car train.

[0131] In a preferred embodiment of the present application, the lateral force and vertical force exerted on the tires of each axle in the double-trailer car train are positively correlated with the driving speed; the driving speed of the double-trailer car train and the preset road adhesion coefficient are random variables; wherein the preset road adhesion coefficient is in a normal distribution range determined based on different road conditions.

[0132] In a preferred embodiment of the present application, the system further comprises:

[0133] The random variable assignment module is used to randomly assign values ​​to the vehicle mass, driving speed and the preset road adhesion coefficient of the double-trailer vehicle train.

[0134] In a preferred embodiment of the present application, the rollover evaluation index determination module 203 includes:

[0135] The lateral load transfer ratio determination submodule is used to determine the vertical load values ​​​​acting on the left and right tires of the double-trailer car train based on the downhill curved road section data; and determine the ratio of the difference between the vertical load values ​​​​acting on the left and right tires to the sum of the vertical load values ​​​​acting on the left and right tires as the lateral load transfer ratio of the double-trailer car train.

[0136] In a preferred embodiment of the present application, the folding evaluation index determination module 204 includes:

[0137] The folding evaluation index determination submodule is used to determine the maximum value from the first articulation angle and the second articulation angle as the target articulation angle; and calculate the folding evaluation index of the double-trailer car train based on the target articulation angle and a preset safety threshold.

[0138] In a preferred embodiment of the present application, the folding evaluation index determination module 204 includes:

[0139] The articulation angle determination submodule is used to determine the first articulation angle between the tractor and the semi-trailer, and the second articulation angle between the semi-trailers according to the downhill curved road section data through a preset dynamic simulation model.

[0140] It should be noted that the double-trailer train driving safety assessment system provided in the above embodiment is similar to the above Figure 1 The provided double-trailer train driving safety assessment method belongs to the same concept. The specific implementation process can refer to the above system embodiment and will not be repeated here.

[0141] Example 3

[0142] The present application provides a device for evaluating the driving safety of a double-trailer train, the device comprising:

[0143] at least one processor; and

[0144] a memory communicatively coupled to the at least one processor; wherein:

[0145] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any of the above-mentioned methods for evaluating the driving safety of a double-trailer train.

[0146] Example 4

[0147] Figure 3 For the double-trailer train driving safety assessment equipment in this application, such as Figure 3 As shown, the double-trailer train driving safety assessment device 300 includes at least one processor 301 and a memory 302 for storing a computer program that can be run on the processor 301. The processor 301 is used to execute the double-trailer train driving safety assessment method suggested by the above embodiment of the present application when running the computer program. The double-trailer train driving safety assessment device 300 also includes at least one network interface 304 and a user interface 303. The various components in the double-trailer train driving safety assessment device 300 are coupled together through a bus system 305. It can be understood that the bus system 305 is used to realize the connection and communication between these components. In addition to the data bus, the bus system 305 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, Figure 3 Various buses are labeled as bus system 305 .

[0148] The user interface 303 may include a display, a keyboard, a mouse, a trackball, a click wheel, keys, buttons, a touch pad or a touch screen.

[0149] It is understood that memory 302 can be volatile memory or non-volatile memory, or can include both volatile and non-volatile memory. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), ferromagnetic random access memory (FRAM), flash memory, magnetic surface memory, optical disk, or compact disc read-only memory (CD-ROM); magnetic surface memory can be magnetic disk memory or tape memory. Volatile memory can be random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), synchronous static random access memory (SSRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct rambus random access memory (DRRAM).The memory 302 described in the embodiments of the present application is intended to include, but is not limited to, these and any other suitable types of memories.

[0150] The memory 302 in the embodiment of the present application is used to store various types of data to support the operation of the double-trailer train driving safety assessment device 300. Examples of these data include: any computer program used to operate on the double-trailer train driving safety assessment device 300, such as an operating system 3021, an application 3022, and a double-trailer train driving safety assessment system 3023; wherein the operating system 3021 includes various system programs, such as a framework layer, a core library layer, a driver layer, etc., for implementing various basic services and processing hardware-based tasks. The application 322 can include various applications, such as a media player (Media Player), a browser (Browser), etc., for implementing various application services. The double-trailer train driving safety assessment system 3023 is the embodiment of the present application. Figure 2 The system shown is used to implement cross-CEP simulation. The program for implementing the method of the embodiment of the present application can be included in the application program 3022 or in the double-trailer train driving safety assessment system 3023.

[0151] The processor 301 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by an integrated logic circuit of the hardware in the processor 301 or by instructions in the form of software. The above-mentioned processor 301 may be a general-purpose processor, a digital signal processor (DSP), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The processor 301 can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor can be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed by a hardware decoding processor, or being executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium, which is located in the memory 302. The processor 301 reads the information in the memory 302 and completes the steps of the above method in combination with its hardware.

[0152] In an exemplary embodiment, the double-trailer train driving safety assessment device 300 can be implemented by one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers (MCUs), microprocessors, or other electronic components to perform the aforementioned method.

[0153] In an exemplary embodiment, the present application also provides a computer-readable storage medium, such as a memory 302 including a computer program. This computer program can be executed by a processor 301 of a double-trailer train driving safety assessment device 300 to complete the steps of the aforementioned method. The computer-readable storage medium can be a memory device such as FRAM, ROM, PROM, EPROM, EEPROM, Flash Memory, magnetic surface storage, optical disk, or CD-ROM; or various devices including any one or any combination of the aforementioned memory devices, such as a computer, tablet device, or personal digital assistant.

[0154] A computer-readable storage medium stores a computer program, which, when executed by a processor, executes the compressor surge warning method suggested by the above-mentioned embodiment of the present application.

[0155] In the several embodiments provided herein, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. In addition, the features disclosed in the several method or device embodiments provided herein can be combined in any manner, unless they conflict, to form new method or device embodiments.

[0156] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A method for evaluating the driving safety of a double-trailer train, characterized in that: The method comprises: Get downhill curve road section data; Determining the maximum lateral adhesion coefficient of the axles of the double-trailer train based on the downhill curved road section data; Calculating a sideslip evaluation index of the double-trailer train based on the maximum lateral adhesion coefficient of the axle and a preset road adhesion coefficient; Determining a lateral load transfer ratio of the double-trailer car train based on the downhill curved road section data, and calculating a rollover evaluation index of the double-trailer car train based on the lateral load transfer ratio and a preset stability threshold; Determining a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers based on the downhill curved road section data, and calculating a folding evaluation index of the double-trailer vehicle train based on the first articulation angle and the second articulation angle; The out-of-control probability of the double-trailer car train is determined based on the sideslip evaluation index data, the rollover evaluation index and the folding evaluation index.

2. The method for evaluating the running safety of a double-trailer train according to claim 1, characterized in that: The downhill curve road section data includes: road surface circular curve radius, transverse slope data and longitudinal slope data.

3. The method for evaluating the running safety of a double-trailer train according to claim 1, characterized in that: The step of determining the maximum lateral adhesion coefficient of the axles of the double-trailer vehicle train based on the downhill curved road section data includes: Determining the lateral force and vertical force exerted on the tires of each axle of the double-trailer vehicle train based on the downhill curved road section data; The ratio of the lateral force to the vertical force exerted on the tires of each axle is determined, and the maximum value of the absolute value of the ratio is determined as the maximum lateral adhesion coefficient of the axle of the double-trailer car train.

4. The method for evaluating the running safety of a double-trailer train according to claim 3 is characterized in that: The lateral force and vertical force exerted on the tires of each axle in the double-trailer car train are positively correlated with the driving speed; the driving speed of the double-trailer car train and the preset road adhesion coefficient are random variables; wherein the preset road adhesion coefficient is within a normal distribution range determined based on different road conditions.

5. The method for evaluating the running safety of a double-trailer train according to claim 4 is characterized in that: Before the step of determining the maximum lateral adhesion coefficient of the axles of the double-trailer vehicle train based on the downhill curved road section data, the method further includes: Randomly assign values ​​to the vehicle mass, driving speed and the preset road adhesion coefficient of the double-trailer vehicle train.

6. The method for evaluating the running safety of a double-trailer train according to claim 1, characterized in that: Determining the lateral load transfer ratio of the double-trailer train based on the downhill curved road section data includes: Determining vertical load values ​​on the left and right tires of the double-trailer train respectively based on the downhill curved road section data; The ratio of the difference between the vertical load values ​​on the left and right tires to the total vertical load values ​​on the left and right tires is determined as the lateral load transfer ratio of the double-trailer train.

7. The method for evaluating the running safety of a double-trailer train according to claim 1, characterized in that: The folding evaluation index of the double-trailer vehicle train is calculated based on the first articulation angle and the second articulation angle, including: determining a maximum value from the first articulation angle and the second articulation angle as a target articulation angle; A folding evaluation index of the double-trailer car train is calculated based on the target articulation angle and a preset safety threshold.

8. The method for evaluating the running safety of a double-trailer train according to claim 1, characterized in that: The determining of a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers according to the downhill curved road section data includes: A first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers are determined according to the downhill curved road section data through a preset dynamic simulation model.

9. A double-trailer train driving safety assessment system, characterized in that: The system comprises: A data acquisition module is used to acquire downhill curved road section data; a sideslip evaluation index determination module, configured to determine a maximum lateral adhesion coefficient of an axle of a double-trailer vehicle train based on the downhill curved road section data; and calculate a sideslip evaluation index of the double-trailer vehicle train based on the maximum lateral adhesion coefficient of the axle and a preset road adhesion coefficient; a rollover evaluation index determination module, configured to determine a lateral load transfer ratio of the double-trailer car train based on the downhill curved road section data, and calculate a rollover evaluation index of the double-trailer car train based on the lateral load transfer ratio and a preset stability threshold; a folding evaluation index determination module, configured to determine a first articulation angle between the tractor and the semi-trailer, and a second articulation angle between the semi-trailers based on the downhill curved road section data, and calculate a folding evaluation index of the double-trailer vehicle train based on the first articulation angle and the second articulation angle; The out-of-control probability determination module is used to determine the out-of-control probability of the double-trailer car train based on the sideslip evaluation index data, the rollover evaluation index and the folding evaluation index.

10. A double-trailer train driving safety assessment device, characterized in that: The device comprises: at least one processor; and a memory communicatively coupled to the at least one processor; wherein: The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the double-trailer train driving safety assessment method according to any one of claims 1 to 8.

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