Trailer swing detection and control method, device, equipment, storage medium and product

Abstract

The present application provides a kind of trailer swing detection and control method, device, equipment, storage medium and product, method includes: obtaining the motion state data of tractor under current detection period measured by electronic stability control sensor, and based on the motion state data of tractor under current detection period calculation obtains yaw angular velocity difference signal;According to yaw angular velocity difference signal, it is judged whether trailer swing occurs;If trailer swing occurs, it is judged whether the driver has taken swing measure;If the driver has not taken swing measure, brake intervention control is carried out to make trailer stop swing.The scheme of the present application can timely find the abnormal swing of trailer by using the existing sensor signals of vehicle, so as to take corresponding control measures, improve the stability and safety of vehicle system, and save the cost of trailer swing detection and control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, and in particular to a trailer swing detection and control method, device, equipment, storage medium and product. BACKGROUND

[0002] The tractor and trailer are common vehicle combinations in road transport, mainly used for cargo transportation. Among them, the tractor, also known as the tow head or the head, is the power and control part of the vehicle. It is connected to the trailer and provides power for it (in some cases, the trailer may have its own power), while controlling the direction and speed of travel. The trailer is a non-powered vehicle connected behind the tractor for carrying goods. The trailer relies on the tractor to move.

[0003] When the tractor pulls the trailer to travel, if the tractor reciprocating steering or the influence of the side wind, it is possible to form the phenomenon of the trailer reciprocating swing around the saddle joint. It has a great impact on the safe driving of the vehicle or the surrounding vehicles. Since the trailer often lacks sensors to measure the corresponding variables, how to detect the swing of the trailer in time and attenuate it through active control is a technical problem of tractor stability control.

[0004] In the prior art, the detection and control of the trailer swing basically need to be realized by additionally increasing sensors or actuators. On the one hand, the cost of trailer swing detection and control is high. On the other hand, after detecting the trailer swing, it cannot be effectively suppressed in time, thereby affecting the stability and safety of the entire vehicle system.

[0005] Therefore, the existing trailer swing detection and control has high cost, and the stability and safety of the vehicle system are poor. SUMMARY

[0006] The present application provides a trailer swing detection and control method, device, equipment, storage medium and product, which solves the defects of high cost of existing trailer swing detection and control in the prior art, and poor stability and safety of the vehicle system, and realizes improving the stability and safety of the vehicle system while saving the cost of trailer swing detection and control.

[0007] The present application provides a trailer swing detection and control method applied to a vehicle running system, wherein the vehicle running system comprises a tractor, a trailer, a trailer swing detection and control device, and an electronic stability control sensor deployed on the tractor; the method comprises the following steps.

[0008] The trailer swing detection and control device acquires motion state data of the towing vehicle in the current detection period measured by the electronic stability control sensor, and calculates a yaw rate difference signal based on the motion state data of the towing vehicle in the current detection period; wherein the motion state data of the towing vehicle includes: steering wheel angle of the towing vehicle, vehicle speed of the towing vehicle, front wheel angle of the towing vehicle, wheelbase of the towing vehicle, characteristic vehicle speed of the towing vehicle, and actual yaw rate of the towing vehicle.

[0009] The trailer swing detection and control device judges whether the trailer swings according to the yaw rate difference signal.

[0010] If the trailer swings, the trailer swing detection and control device judges whether the driver has taken a swing measure.

[0011] If the driver does not take a swing measure, the trailer swing detection and control device performs brake intervention control to stop the trailer from swinging; wherein the brake intervention control includes: reducing the engine torque value of the towing vehicle at a predetermined rate; applying brake pressure to each axle of the trailer, the front axle of the towing vehicle, and the rear axle of the towing vehicle at a preset fixed ratio to reduce the longitudinal acceleration of the vehicle operation system.

[0012] According to the trailer swing detection and control method provided by the application, the yaw rate difference signal is calculated based on the motion state data of the towing vehicle in the current detection period, including the following steps.

[0013] The trailer swing detection and control device calculates the target yaw rate at each time point in the current detection period based on the steering wheel angle of the towing vehicle, the vehicle speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic vehicle speed of the towing vehicle.

[0014] The trailer swing detection and control device calculates the difference between the actual yaw rate and the target yaw rate at each time point in the current detection period to obtain the yaw rate difference signal.

[0015] According to the trailer swing detection and control method provided by the application, the trailer swing detection and control device judges whether the trailer swings according to the yaw rate difference signal, including the following steps.

[0016] The trailer swing detection and control device performs system identification on the yaw rate difference signal to obtain the vibration amplitude of the yaw rate difference signal.

[0017] The trailer swing detection and control device judges whether the vibration amplitude value of the yaw angular velocity difference signal is greater than a preset first threshold value; if greater, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing.

[0018] According to the trailer swing detection and control method provided by the application, the trailer swing detection and control device judges whether the trailer swings according to the yaw angular velocity difference signal, including the following steps.

[0019] The trailer swing detection and control device performs first-order low-pass filtering on the yaw angular velocity difference signal to obtain a first filtered signal.

[0020] The trailer swing detection and control device performs second-order Butterworth filtering on the first filtered signal to obtain a second filtered signal.

[0021] The trailer swing detection and control device calculates the difference between the maximum value and the minimum value of the second filtered signal in each steady-state evaluation period to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period includes multiple steady-state evaluation periods.

[0022] The trailer swing detection and control device takes the maximum value of the steady-state swing amplitude in the current detection period as the vibration intensity value in the current detection period.

[0023] The trailer swing detection and control device calculates the average value of the vibration intensity value in the current integration period to obtain a vibration reinforcement average value; wherein the integration period includes multiple detection periods.

[0024] The trailer swing detection and control device calculates the difference between the vibration intensity value at each time and the vibration reinforcement average value in the previous integration period in the current integration period to obtain a vibration reinforcement processing value.

[0025] In the current integration period, the trailer swing detection and control device integrates the vibration reinforcement processing value to obtain a first integral value.

[0026] In the current integration period, the trailer swing detection and control device takes the absolute value of the vibration reinforcement processing value and integrates it to obtain a second integral value.

[0027] The trailer swing detection and control device calculates the difference between the second integral value and the first integral value to obtain an integral difference value.

[0028] The trailer swing detection and control device judges whether the integral difference value is greater than a preset second threshold value; if greater, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing.

[0029] According to the trailer swing detection and control method provided by the application, after the brake intervention control is performed, the method further comprises the following steps.

[0030] The trailer swing detection and control device judges whether the integral difference value is greater than a preset third threshold value, and if so, increases the pressure of the outer front wheel of the towing vehicle; wherein the third threshold value is greater than the second threshold value.

[0031] According to the trailer swing detection and control method provided by the application, the trailer swing detection and control device judges whether the driver has taken the swing elimination measure, comprising the following steps.

[0032] Obtain the current brake pedal opening and the current steering wheel angle of the towing vehicle.

[0033] If the current brake pedal opening is greater than a preset fourth threshold value, and the current steering wheel angle is greater than a preset fifth threshold value, the trailer swing detection and control device determines that the driver has taken the swing elimination measure, otherwise, it is determined that the driver has not taken the swing elimination measure.

[0034] The application also provides a trailer swing detection and control device, which is applied to a vehicle operation system, the vehicle operation system comprising a towing vehicle, a trailer, a trailer swing detection and control device and an electronic stability control sensor arranged on the towing vehicle, and the device comprising the following modules.

[0035] The acquisition module is used to acquire the motion state data of the towing vehicle measured by the electronic stability control sensor in the current detection period;

[0036] The calculation module is used to calculate the yaw rate difference value signal based on the motion state data of the towing vehicle in the current detection period; wherein the operation state data of the towing vehicle comprises the steering wheel angle of the towing vehicle, the speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, the characteristic speed of the towing vehicle and the actual yaw rate of the towing vehicle.

[0037] The first judgment module is used to judge whether the trailer swings according to the yaw rate difference value signal;

[0038] The second judgment module is used to judge whether the driver has taken the swing elimination measure if the trailer swings;

[0039] A control module is configured to perform brake intervention control to stop the trailer from swinging if the driver does not take the countermeasure, wherein the brake intervention control comprises: reducing the engine torque value of the tractor at a predetermined change rate; and applying brake pressure to each axle of the trailer, the front axle of the tractor and the rear axle of the tractor at a preset fixed ratio to reduce the longitudinal acceleration of the vehicle operation system.

[0040] The application further provides an electronic device comprising a memory, a processor and a computer program stored in the memory and running on the processor, wherein the processor implements the trailer swing detection and control method according to any one of the above when executing the computer program.

[0041] The application further provides a non-transitory computer readable storage medium having a computer program stored thereon, wherein the computer program is executed by a processor to implement the trailer swing detection and control method according to any one of the above.

[0042] The application further provides a computer program product comprising a computer program, wherein the computer program is executed by a processor to implement the trailer swing detection and control method according to any one of the above.

[0043] The trailer swing detection and control method, device, equipment, storage medium and product provided by the application can obtain the motion state data of the tractor measured by the existing electronic stability control sensor, and calculate a yaw rate difference signal. According to the yaw rate difference signal, the abnormal swing of the trailer can be found in time, so that corresponding control measures can be taken, and the cost of trailer swing detection and control is saved. Further, when the driver does not take the countermeasure after detecting the swing of the trailer, brake intervention control is performed in time and effectively to realize the timely and effective control of the trailer swing, and the stability and safety of the vehicle system are improved. In conclusion, the scheme of the application can improve the stability and safety of the vehicle system while saving the cost of trailer swing detection and control. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0045] Figure 1 is a schematic diagram of trailer swing provided by the application.

[0046] Figure 2 is a flowchart of the trailer swing detection and control method provided by the application.

[0047] Figure 3 is a structural schematic diagram of a trailer swing detection and control device provided by the present application.

[0048] Figure 4 is a structural schematic diagram of an electronic device provided by the present application. DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are only a 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 work fall within the scope of protection of the present application.

[0050] It should be noted that the brief description of the terms in the present application is only for the convenience of understanding the subsequently described embodiments, and is not intended to limit the embodiments of the present application. Unless otherwise specified, these terms should be understood according to their ordinary and general meanings.

[0051] The terms "first", "second", and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar or similar objects or entities, and do not necessarily mean a specific order or sequence, unless otherwise indicated. It should be understood that the terms used in this way can be interchanged under appropriate circumstances, for example, those other than the order given in the embodiment illustration or description of the present application can be implemented.

[0052] In addition, the terms "include" and "have" and any variations thereof are intended to cover but not exclusive inclusion, for example, a product or device including a series of components does not have to be limited to those components clearly listed, but can include other components not clearly listed or inherent to these products or devices. The term "module" used in the present application refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or a combination of hardware or / and software code capable of performing functions related to the element.

[0053] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0054] A tractor and a trailer are common vehicle combinations in road transport, mainly used for cargo transport. The tractor, also known as the tow head or the head, is the power and control part of the vehicle. It is connected to the trailer and provides power for it (in some cases, the trailer may have its own power), while controlling the direction and speed of travel. The trailer is a non-powered vehicle connected behind the tractor for carrying goods. The trailer relies on the tractor to move.

[0055] Figure 1 is a schematic diagram of the trailer swing provided by the present application, as Figure 1 shown, w t is the actual yaw rate, w m is the steering wheel angle. In practice, when the tractor 10 pulls the trailer 20, if the tractor 10 reciprocating steering or the influence of crosswind, it is possible to form the phenomenon of the trailer 20 reciprocating swing around the saddle joint, which has a greater impact on the safe driving of the vehicle or the surrounding vehicles. Since the trailer 20 often lacks sensors to measure the corresponding variables, how to detect the swing of the trailer 20 in time and attenuate it through active control is a technical problem of the stability control of the tractor 10.

[0056] In the prior art, the detection and control of the trailer swing basically need to be realized by additionally increasing sensors or actuators. On the one hand, the cost of the trailer swing detection and control is high. On the other hand, after the trailer swing is detected, it cannot be effectively suppressed in time, thereby affecting the stability and safety of the entire vehicle system.

[0057] Therefore, the existing trailer swing detection and control has high cost, and the stability and safety of the vehicle system are poor.

[0058] To solve the above technical problems, the present application proposes the following technical ideas: the yaw rate difference signal is calculated by using the existing sensor signals of the vehicle; the yawing of the trailer is detected according to the yaw rate difference signal, and the accurate detection of the yawing of the trailer can be realized without additional sensors or actuators, thereby saving the cost of the detection and control of the yawing of the trailer. Further, when the yawing of the trailer is detected and the driver does not take yawing measures, the brake intervention control is timely performed to realize the timely and effective control of the yawing of the trailer, thereby improving the safety and stability of the vehicle operation system.

[0059] The technical solutions of the present application and how the technical solutions of the present application solve the above technical problems will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes can not be described in some embodiments. The following embodiments are combined with Figure 2 The trailer yawing detection and control method of the present application is described.

[0060] Figure 2 The flowchart of the trailer yawing detection and control method provided by the present application is shown in FIG. 1, which includes the following steps 201 to 205. Figure 2

[0061] In practical applications, the execution subject of the trailer yawing detection and control method can be a trailer yawing detection and control device, and the trailer yawing detection and control device can be implemented in various ways, such as through a computer program, for example, application software, etc.; or, for example, a chip, etc. It can also be implemented as a medium storing a related computer program, for example, a U disk, a cloud disk, etc.; or, it can also be implemented through an entity device integrated or installed with a related computer program, such as a server, etc.

[0062] Specifically, the trailer yawing detection and control method provided by the present application is applied to a vehicle operation system, which includes a tractor, a trailer, a trailer yawing detection and control device, and an electronic stability control sensor arranged on the tractor.

[0063] Step 201: The trailer yawing detection and control device acquires the motion state data of the tractor in the current detection period measured by the electronic stability control sensor.

[0064] ​Among them, the electronic stability control sensor (Electronic Stability Control Sensor, ESC sensor) is a general term for a set of sensor systems used in existing vehicles to monitor the dynamic state of the vehicle and assist in maintaining the stability of the vehicle. The ESC sensor is an important part of automotive safety technology. It collects motion state data through a series of sensors and automatically adjusts the vehicle's braking and power output when necessary to help the driver maintain control of the vehicle.

[0065] For example, the ECS sensor includes but is not limited to: yaw rate sensor, lateral acceleration sensor, steering wheel angle sensor, wheel speed sensor, vehicle speed sensor, brake pressure sensor, vehicle position sensor.

[0066] In this embodiment, the operating state data of the tractor includes: the steering wheel angle of the tractor, the speed of the tractor, the front wheel angle of the tractor, the wheelbase of the tractor, the characteristic speed of the tractor and the actual yaw rate of the tractor.

[0067] Among them, the detection period refers to the period of detecting the swing of the trailer. The length of the detection period can be set according to actual needs. In actual application, when the current detection period comes, the operating state data of the tractor measured by the ESC is obtained.

[0068] Step 202, the trailer swing detection and control device calculates the yaw rate difference signal based on the motion state data of the tractor in the current detection period.

[0069] Among them, the yaw rate difference signal dw is the difference between the actual yaw rate w t and the target yaw rate w0. In vehicle dynamics, yaw rate is the rate of rotation of the vehicle around the vertical axis, which can reflect the stability and maneuverability of the vehicle when turning or subjected to lateral forces.

[0070] Specifically, the target yaw rate w0 is the ideal yaw rate calculated by the motion state data of the tractor, and the target yaw rate w0 reflects the yaw rate that the vehicle should achieve under the current steering and speed conditions to achieve smooth turning. The actual yaw rate w tis the actual yaw rate measured by the ESC sensor, the actual yaw rate w t reflects the actual dynamic behavior of the vehicle.

[0071] In this embodiment, the actual yaw rate w t is subtracted from the target yaw rate w0, and a yaw rate difference signal dw is obtained. The yaw rate difference signal dw can be used to detect and analyze the stability of the vehicle. If the dynamic behavior of the vehicle is consistent with the expectation, dw is close to zero. If dw deviates greatly, it indicates that the stability of the vehicle is affected, for example, the swing of the trailer.

[0072] Optionally, in one possible implementation, the above step 202 comprises:

[0073] The trailer swing detection and control device calculates the target yaw rate at each time point of the current detection period based on the steering wheel angle of the towing vehicle, the vehicle speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic vehicle speed of the towing vehicle at each time point of the current detection period.

[0074] The trailer swing detection and control device calculates the difference between the actual yaw rate and the target yaw rate at each time point of the current detection period, and obtains a yaw rate difference signal.

[0075] In one example, the target yaw rate at each time point of the current detection period can be calculated by a mathematical model (Ackermann model) based on the steering wheel angle of the towing vehicle, the vehicle speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic vehicle speed of the towing vehicle.

[0076] Specifically, when the steering wheel angle of the towing vehicle reaches a predetermined value or angle, the Ackermann vehicle model is used to calculate the target yaw rate. The Ackermann vehicle model is a simplified vehicle dynamics model that assumes that all wheels of the vehicle move along the same circular path when turning, and the steering angles of the inner and outer wheels are related to the wheelbase of the vehicle and the turning radius. In this model, the target yaw rate is calculated based on the steering wheel angle of the towing vehicle, the vehicle speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic vehicle speed of the towing vehicle, and is used to describe the yaw dynamics of the vehicle in an ideal case.

[0077] Specifically, when the driver turns the steering wheel to a predetermined angle, the angle is taken as one of the input parameters, combined with the speed of the towing vehicle, the front wheel steering angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic speed of the towing vehicle, to calculate the target yaw rate of the vehicle under the steering condition through the Ackerman model. The target yaw rate reflects the yaw dynamics that the vehicle should have under the current steering and speed conditions in order to achieve stable turning. By comparing the actual yaw rate with the target yaw rate, it can be evaluated whether the actual dynamics of the vehicle are consistent with the expected, and then used for detecting and controlling the stability of the vehicle, especially in a system composed of a towing vehicle and a trailer, which is particularly important for detecting and suppressing the swing of the trailer.

[0078] Specifically, the expression of the target yaw rate w0 is as follows:

[0079]

[0080] wherein w0 is the target yaw rate, v is the speed of the towing vehicle, l is the wheelbase of the towing vehicle, δ is the front wheel steering angle of the towing vehicle, v ch is the characteristic speed of the towing vehicle.

[0081] In this embodiment, the yaw rate difference signal is calculated based on the motion state data of the towing vehicle under the current detection period, and the yaw rate difference signal is a key indicator for detecting the swing state of the trailer. Through the yaw rate difference signal, it can be accurately identified whether the trailer has swung.

[0082] In the present application, the target yaw rate is calculated based on the motion state data measured by the ESC sensor. By comparing the actual yaw rate directly measured by the ESC sensor with the target yaw rate, it can be evaluated whether the trailer has swung, and corresponding control can be performed to improve the stability and safety of the vehicle operation system.

[0083] Step 203, the trailer swing detection and control device judges whether the trailer has swung according to the yaw rate difference signal.

[0084] In the present application, the judgment method for the swing of the trailer is not specifically limited. As an example, a swing discrimination model is established and trained based on a machine learning network. The yaw rate difference signal is input into the swing discrimination model, and the swing discrimination result output by the swing discrimination model can be obtained.

[0085] In actual application, when the trailer swings, dw will periodically vibrate, therefore, the swing of the trailer is detected by recognizing the vibration characteristics of dw. Specifically, when the vibration characteristics reach a certain threshold value, it is considered that the trailer has swung.

[0086] Optionally, in one possible implementation, the above step 203 comprises:

[0087] The trailer swing detection and control device performs system identification on the yaw rate difference signal to obtain a vibration amplitude of the yaw rate difference signal;

[0088] The trailer swing detection and control device determines whether the vibration amplitude of the yaw rate difference signal is greater than a preset first threshold value; if yes, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing.

[0089] The system identification refers to a process of describing and analyzing the dynamic behavior of a system through a mathematical model. In this embodiment, by performing system identification on the yaw rate difference signal dw, the characteristic of trailer swing, i.e., the vibration amplitude, can be extracted. The vibration amplitude reflects the strength of trailer swing, i.e., the swing amplitude.

[0090] Further, the calculated vibration amplitude is compared with the preset first threshold value. This first threshold value is set according to the characteristics of trailer swing, and is used to distinguish whether the trailer swings. If the vibration amplitude is greater than the first threshold value, it means that the swing amplitude of the trailer exceeds the normal range, and it can be determined that the trailer swings. Conversely, if the vibration amplitude is less than or equal to the first threshold value, it means that the swing amplitude of the trailer is within the normal range, and it can be determined that the trailer does not swing.

[0091] In this embodiment, the system identification is performed on the yaw rate difference signal to obtain the vibration amplitude of the yaw rate difference signal, and the vibration amplitude is compared with the first threshold value to determine whether the trailer swings, which provides a basis for the subsequent control strategy. When it is detected that the trailer swings, appropriate control measures can be taken, such as adjusting the braking force or engine torque, to attenuate the swing of the trailer, thereby improving the stability and safety of the vehicle.

[0092] Optionally, in a possible implementation, the step 203 comprises:

[0093] The trailer swing detection and control device performs first-order low-pass filtering on the yaw rate difference signal to obtain a first filtered signal;

[0094] The trailer swing detection and control device performs second-order Butterworth filtering on the first filtered signal to obtain a second filtered signal;

[0095] The trailer swing detection and control device calculates the difference between the maximum value and the minimum value of the second filtered signal in each steady-state evaluation period to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period comprises a plurality of steady-state evaluation periods;

[0096] The trailer swing detection and control device takes the maximum value of the steady-state swing amplitude in the current detection period as the vibration strength value in the current detection period.

[0097] The trailer swing detection and control device calculates an average value of the vibration intensity value in the current integration period, to obtain a vibration reinforcement average value; wherein the integration period includes multiple detection periods.

[0098] The trailer swing detection and control device calculates a difference value between the vibration intensity value at each time point in the current integration period and the vibration reinforcement average value in the previous integration period, to obtain a vibration reinforcement processing value.

[0099] In the current integration period, the trailer swing detection and control device integrates the vibration reinforcement processing value to obtain a first integral value.

[0100] In the current integration period, the trailer swing detection and control device takes the absolute value of the vibration reinforcement processing value and integrates it to obtain a second integral value.

[0101] The trailer swing detection and control device calculates a difference value between the second integral value and the first integral value, to obtain an integral difference value.

[0102] The trailer swing detection and control device determines whether the integral difference value is greater than a preset second threshold value; if it is greater, it is determined that the trailer is swinging, otherwise it is determined that the trailer is not swinging.

[0103] In actual application, in order to eliminate the burr in the yaw rate difference signal dw, the yaw rate difference signal dw is filtered. Specifically, the yaw rate difference signal dw is first-order low-pass filtered to obtain a first filtered signal dw1, to ensure that there is no large phase delay caused by filtering. Further, the first filtered signal dw1 is second-order Butterworth filtered, mainly used to capture the amplitude characteristics of dw in the current detection period, to obtain a second filtered signal dw2. The difference between the maximum value and the minimum value of the second filtered signal dw2 in each steady-state evaluation period is calculated to obtain the steady-state swing amplitude Adw in each steady-state evaluation period; wherein the current detection period includes multiple steady-state evaluation periods. Further, the maximum value of the steady-state swing amplitude Adw in the current detection period is taken as the vibration intensity value Adwm in the current detection period, as the basis for determining whether the trailer is swinging.

[0104] Further, the average value of the vibration intensity value Adwm in the current integration period is calculated to obtain a vibration reinforcement average value aAdwm; wherein the integration period includes multiple detection periods.

[0105] Further, the difference value between the vibration intensity value Adwm at each time point in the current integration period and the vibration reinforcement average value aAdwm in the previous integration period is calculated to obtain a vibration reinforcement processing value dAdwm.

[0106] Further, the vibration strengthening processing value dAdwm is integrated in the current integration period to obtain a first integrated value IdAdwm.

[0107] Further, the vibration strengthening processing value dAdwm is integrated in the current integration period to obtain a first integrated value IdAdwm.

[0108] Further, the vibration strengthening processing value dAdwm is integrated in the current integration period to obtain a first integrated value IdAdwm.

[0109] Further, the vibration strengthening processing value dAdwm is integrated in the current integration period to obtain a first integrated value IdAdwm.

[0110] Optionally, in a possible implementation, the step 203 comprises:

[0111] The trailer swing detection and control device performs first-order low-pass filtering on the yaw rate difference signal to obtain a first filtered signal;

[0112] The trailer swing detection and control device performs second-order Butterworth filtering on the first filtered signal to obtain a second filtered signal;

[0113] The trailer swing detection and control device calculates the difference between the maximum value and the minimum value of the second filtered signal in each steady-state evaluation period to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period comprises a plurality of steady-state evaluation periods.

[0114] The trailer swing detection and control device judges whether the steady-state swing amplitude is greater than a preset sixth threshold value; if greater, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing.

[0115] Step 204, if the trailer swings, the trailer swing detection and control device judges whether the driver has taken measures to eliminate the swing.

[0116] In actual application, after it is determined that the trailer has swung, the next step is to judge whether the driver has taken measures to eliminate or reduce the swing. The purpose of this step is to decide whether the trailer swing detection and control device needs to intervene and how to intervene to ensure the stability and safety of the vehicle.

[0117] It can be understood that step 204 is to ensure that the trailer swing detection and control device does not conflict with the operation of the driver, and can provide appropriate assistance when necessary to improve the maneuverability and safety of the vehicle. By intelligently judging the intention and operation of the driver, the trailer swing detection and control device can more effectively manage the dynamic behavior of the vehicle, especially in complex vehicle operation systems.

[0118] As an example, in one possible implementation, the trailer swing detection and control device determines whether the driver has taken the swing elimination measure in step 204 above, including:

[0119] The trailer swing detection and control device obtains the current brake pedal opening and the current steering wheel angle of the tractor.

[0120] If the current brake pedal opening is greater than a preset fourth threshold value, and the current steering wheel angle is greater than a preset fifth threshold value, the trailer swing detection and control device determines that the driver has taken the swing elimination measure, otherwise, it is determined that the driver has not taken the swing elimination measure.

[0121] In practical applications, the fourth threshold value and the fifth threshold value can be preset according to historical data or experimental data of the vehicle operation system. It can be understood that if the current brake pedal opening is greater than the preset fourth threshold value THb, and the current steering wheel angle is greater than the preset fifth threshold value THs, it indicates that the driver has taken the swing elimination measure, and the system does not actively trigger the swing elimination control at this time. The response to the driver input is given priority.

[0122] Step 205, if the driver does not take the swing elimination measure, the trailer swing detection and control device performs brake intervention control to stop the trailer from swinging; wherein the brake intervention control includes: reducing the engine torque value of the tractor according to a predetermined change rate; applying brake pressure to each axle of the trailer, the front axle of the tractor and the rear axle of the tractor according to a preset fixed ratio, to reduce the longitudinal acceleration of the vehicle operation system.

[0123] Specifically, the torque output of the tractor engine is reduced according to a predetermined change rate, which can reduce the driving force of the vehicle and thus reduce the instability caused by the trailer swing. In practical applications, the change rate of torque reduction can be calibrated according to the test results of the actual vehicle to ensure the control effect while avoiding excessive impact on the driving performance of the vehicle.

[0124] Specifically, brake pressure is applied to each axle of the trailer and the front axle and the rear axle of the towing vehicle according to a preset fixed ratio, which can be determined according to the brake pressure distribution ratio when the brake system is designed, for example, 1:1:1, brake pressure is applied to each axle of the trailer and the front axle and the rear axle of the towing vehicle. The purpose of applying brake pressure is to generate longitudinal deceleration, thereby helping to reduce the speed of the vehicle and further inhibit the swing of the trailer.

[0125] It can be understood that, through brake intervention control, the longitudinal acceleration ax of the vehicle system, i.e., the acceleration in the forward direction of the vehicle, can be reduced, so that the speed of the vehicle is reduced, and the danger caused by further aggravation of the swing is prevented.

[0126] It can be understood that, if the driver takes the swing reduction measure, the trailer swing detection and control device does not perform brake intervention control. Alternatively, the trailer swing detection and control device continues to monitor the swing of the trailer, and if the trailer is still in the swing state after a period of time, the trailer swing detection and control device performs brake intervention control to assist the driver to take the swing reduction measure, so as to achieve timely and effective control of the swing of the trailer, thereby improving the stability and safety of the vehicle system.

[0127] In the embodiment, the motion state data of the towing vehicle measured by the existing electronic stability control sensor is obtained, and the yaw rate difference signal is calculated. According to the yaw rate difference signal, the abnormal swing of the trailer can be found in time, so that corresponding control measures are taken, and the cost of trailer swing detection and control is saved. Further, after detecting the swing of the trailer and when the driver does not take the swing reduction measure, brake intervention control is timely and effectively performed, so as to achieve timely and effective control of the swing of the trailer, thereby improving the stability and safety of the vehicle system. As can be seen from the above, the scheme of the embodiment saves the cost of trailer swing detection and control while improving the stability and safety of the vehicle system.

[0128] In addition, when the value of dIdAdwm further increases and is greater than a preset third threshold THdIdAdwm2, the pressure on the front and rear wheels outside the main vehicle (towing vehicle) on the swing direction corresponding to the current yaw rate w can be slightly greater than that on the inside wheels, that is, the pressure dP is additionally increased on the outside wheels, so as to correct the possible over-steering condition and better stabilize the vehicle posture when the swing is large. The specific value of dP can be determined according to experience or real vehicle test calibration.

[0129] Alternatively, in a possible implementation, after the step 205, the method further includes:

[0130] The trailer swing detection and control device judges whether the integral difference value is greater than a preset third threshold value, and if greater, increases the pressure of the outer front wheel of the towing vehicle; Wherein, the third threshold value is greater than the second threshold value.

[0131] In this embodiment, when the integral difference value of the yaw rate difference signal dIdAdwm exceeds the preset third threshold value THdIdAdwm2, additional pressure dP is applied to the outer wheels of the towing vehicle, which can more effectively suppress the swing of the trailer and enhance the stability of the vehicle.

[0132] The trailer swing detection and control method provided in the embodiment acquires the motion state data of the towing vehicle measured by the existing electronic stability control sensor, and calculates the yaw rate difference signal. According to the yaw rate difference signal, the abnormal swing of the trailer can be found in time, so that corresponding control measures can be taken, and the cost of trailer swing detection and control is saved. Further, after detecting the swing of the trailer, and when the driver does not take swing measures, brake intervention control is timely and effectively performed to realize timely and effective control of the trailer swing, and the stability and safety of the vehicle system are improved. In summary, the scheme of the embodiment saves the cost of trailer swing detection and control while improving the stability and safety of the vehicle system.

[0133] The trailer swing detection and control device provided by the application is described below, and the trailer swing detection and control device described below can be referred to each other corresponding to the trailer swing detection and control method described above.

[0134] In practical application, the trailer swing detection and control device has many implementation modes, such as computer program, for example, application software, etc.;Or, for example, chip, etc. It can also be realized as a medium storing relevant computer programs, such as U disk, cloud disk, etc.;Or, it can also be realized through an entity device integrated or installed with relevant computer programs, such as server, etc.

[0135] Specifically, the trailer swing detection and control device provided by the application is applied to a vehicle running system, and the vehicle running system comprises a towing vehicle, a trailer, a trailer swing detection and control device, and an electronic stability control sensor arranged on the towing vehicle.

[0136] Figure 3 The structure diagram of the trailer swing detection and control device provided by the application is shown in FIG. 1. Figure 3 As shown in FIG. 1, the trailer swing detection and control device comprises an acquisition module 31, a calculation module 32, a first judgment module 33, a second judgment module 34 and a control module 35.

[0137] The acquisition module 31 is configured to acquire motion state data of the tractor in a current detection period measured by an electronic stability control sensor.

[0138] The electronic stability control sensor (ESC sensor) is a general term for a set of sensor systems used in existing vehicles to monitor vehicle dynamic state and assist in maintaining vehicle stability. The ESC sensor is an important part of automotive safety technology. It collects motion state data through a series of sensors and automatically adjusts the braking and power output of the vehicle when necessary to help the driver maintain control of the vehicle.

[0139] In this embodiment, the motion state data of the tractor includes the steering wheel angle of the tractor, the speed of the tractor, the front wheel angle of the tractor, the wheelbase of the tractor, the characteristic speed of the tractor, and the actual yaw rate of the tractor.

[0140] The detection period refers to the period of detection of the trailer swing. The length of the detection period can be set according to actual needs. In actual application, when the current detection period arrives, the motion state data of the tractor measured by the ESC is acquired.

[0141] In combination Figure 3 , the calculation module 32 is configured to calculate a yaw rate difference signal based on the motion state data of the tractor in the current detection period.

[0142] The yaw rate difference signal dw is the difference between the actual yaw rate w t and the target yaw rate w0. In vehicle dynamics, yaw rate is the rate of rotation of a vehicle around the vertical axis, which can reflect the stability and maneuverability of the vehicle when turning or subjected to lateral forces.

[0143] Specifically, the target yaw rate w0 is the ideal yaw rate calculated from the motion state data of the tractor, which reflects the yaw rate that the vehicle should achieve under the current steering and speed conditions to achieve smooth turning. The actual yaw rate w t is the yaw rate actually measured by the ESC sensor, which reflects the actual dynamic behavior of the vehicle. t

[0144] In this embodiment, the calculation module 32 calculates the actual yaw rate w t ​The target yaw rate w0 is subtracted to obtain a yaw rate difference signal dw. The yaw rate difference signal dw can be used to detect and analyze the stability of the vehicle. If the dynamic behavior of the vehicle is consistent with the expectation, dw is close to zero. If dw deviates greatly, it indicates that the stability of the vehicle is affected, for example, the swing of the trailer.

[0145] Optionally, in one possible implementation, the above-mentioned computing module 32 is specifically used for:

[0146] Based on the steering wheel angle of the towing vehicle, the speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic speed of the towing vehicle at each time point in the current detection period, the target yaw rate at each time point in the current detection period is calculated.

[0147] The difference between the actual yaw rate and the target yaw rate at each time point in the current detection period is calculated to obtain a yaw rate difference signal.

[0148] In one example, based on the steering wheel angle of the towing vehicle, the speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic speed of the towing vehicle at each time point in the current detection period, the computing module 32 can calculate the target yaw rate at each time point in the current detection period through a mathematical model (Ackermann model).

[0149] Specifically, when the steering wheel angle of the towing vehicle reaches a predetermined value or angle, the computing module 32 calculates the target yaw rate using the Ackermann vehicle model. The Ackermann vehicle model is a simplified vehicle dynamics model that assumes that all wheels of the vehicle move along the same circular path when turning, and the steering angles of the inner and outer wheels are related to the wheelbase of the vehicle and the turning radius. In this model, the target yaw rate is calculated based on the steering wheel angle of the towing vehicle, the speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic speed of the towing vehicle, and is used to describe the yaw dynamics of the vehicle in an ideal case.

[0150] Specifically, when the driver turns the steering wheel to a predetermined angle, this angle is used as one of the input parameters, combined with the speed of the towing vehicle, the front wheel angle of the towing vehicle, the wheelbase of the towing vehicle, and the characteristic speed of the towing vehicle, the computing module 32 calculates the target yaw rate of the vehicle under the steering condition through the Ackermann model. The target yaw rate reflects the yaw dynamics that the vehicle should have under the current steering and speed conditions to achieve stable turning. By comparing the actual yaw rate and the target yaw rate, it can be evaluated whether the actual dynamics of the vehicle is consistent with the expectation, and then used to detect and control the stability of the vehicle, especially in a system composed of a towing vehicle and a trailer, which is particularly important for detecting and suppressing the swing of the trailer.

[0151] Specifically, the expression of the target yaw rate w0 is as follows:

[0152]

[0153] wherein w0 is the target yaw rate, v is the vehicle speed of the towing vehicle, l is the wheelbase of the towing vehicle, d is the front wheel steering angle of the towing vehicle, v ch is the characteristic vehicle speed of the towing vehicle.

[0154] In the embodiment, the calculation module 32 calculates the yaw rate difference signal based on the motion state data of the towing vehicle in the current detection period. The yaw rate difference signal is a key indicator for detecting the swing state of the trailer. Through the yaw rate difference signal, it can be accurately identified whether the trailer swings.

[0155] In the present application, the target yaw rate is calculated based on the motion state data measured by the ESC sensor. By comparing the actual yaw rate directly measured by the ESC sensor and the target yaw rate, it can be evaluated whether the trailer swings and the corresponding control is performed to improve the stability and safety of the vehicle operation system.

[0156] In combination Figure 3 , the first judgment module 33 is used to judge whether the trailer swings according to the yaw rate difference signal.

[0157] In the present application, the judgment method of the trailer swing is not specifically limited. As an example, a swing discrimination model is established and trained based on a machine learning network. The yaw rate difference signal is input into the swing discrimination model to obtain the swing discrimination result output by the swing discrimination model.

[0158] In practical application, when the trailer swings, dw will periodically vibrate, therefore, the trailer swing is detected by identifying the vibration characteristics of dw. Specifically, when the vibration characteristics reach a certain threshold value, it is considered that the trailer swings.

[0159] Optionally, in a possible implementation, the first judgment module 33 is specifically used for:

[0160] The yaw rate difference signal is subjected to system identification to obtain the vibration amplitude of the yaw rate difference signal;

[0161] It is judged whether the vibration amplitude of the yaw rate difference signal is greater than a preset first threshold value; if yes, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing.

[0162] The system identification refers to a process of describing and analyzing dynamic behavior of a system through a mathematical model. In the embodiment, the feature of the trailer swing, i.e., the vibration amplitude, can be extracted by performing system identification on the yaw rate difference signal dw.

[0163] Further, the calculated vibration amplitude is compared with a preset first threshold. The first threshold is set according to the characteristics of the trailer swing, and is used to distinguish whether the trailer swings. If the vibration amplitude is greater than the first threshold, it indicates that the swing amplitude of the trailer exceeds the normal range, and it can be determined that the trailer swings. Conversely, if the vibration amplitude is less than or equal to the first threshold, it indicates that the swing amplitude of the trailer is within the normal range, and it can be determined that the trailer does not swing.

[0164] In the embodiment, the system identification is performed on the yaw rate difference signal, the vibration amplitude of the yaw rate difference signal is obtained, and the vibration amplitude is compared with the first threshold to determine whether the trailer swings, thereby providing a basis for subsequent control strategies. When it is detected that the trailer swings, corresponding control measures can be taken, such as adjusting the braking force or the engine torque, to attenuate the swing of the trailer, thereby improving the stability and safety of the vehicle.

[0165] Optionally, in a possible implementation, the first determining module 33 is specifically configured to:

[0166] perform first-order low-pass filtering on the yaw rate difference signal to obtain a first filtered signal;

[0167] perform second-order Butterworth filtering on the first filtered signal to obtain a second filtered signal;

[0168] calculate a difference between a maximum value and a minimum value of the second filtered signal in each steady-state evaluation period to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period includes a plurality of steady-state evaluation periods;

[0169] take a maximum value of the steady-state swing amplitudes in the current detection period as a vibration intensity value in the current detection period;

[0170] calculate an average value of the vibration intensity values in the current integration period to obtain a vibration intensity average value; wherein the integration period includes a plurality of detection periods;

[0171] calculate a difference between the vibration intensity value at each time point in the current integration period and the vibration intensity average value in the previous integration period to obtain a vibration intensity processing value;

[0172] integrate the vibration intensity processing value in the current integration period to obtain a first integral value;

[0173] In the current integration period, the absolute value of the vibration strengthening processing value is taken and integrated to obtain a second integral value;

[0174] The difference between the second integral value and the first integral value is calculated to obtain an integral difference value;

[0175] It is judged whether the integral difference value is greater than a preset second threshold value; if it is greater, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing.

[0176] In actual application, in order to eliminate the burr in the yaw rate difference signal dw, the yaw rate difference signal dw is filtered. Specifically, the yaw rate difference signal dw is first-order low-pass filtered to obtain a first filtered signal dw1, ensuring that there is no large phase delay caused by filtering. Further, the first filtered signal dw1 is second-order Butterworth filtered, mainly used to capture the amplitude characteristics of dw in the current detection period, to obtain a second filtered signal dw2. The difference between the maximum value and the minimum value of the second filtered signal dw2 in each steady-state evaluation period is calculated to obtain the steady-state swing amplitude Adw in each steady-state evaluation period; wherein the current detection period includes multiple steady-state evaluation periods. Further, the maximum value of the steady-state swing amplitude Adw in the current detection period is taken as the vibration intensity value Adwm in the current detection period, as the basis for determining whether the trailer swings.

[0177] Further, the average value of the vibration intensity value Adwm in the current integration period is calculated to obtain a vibration strengthening average value aAdwm; wherein the integration period includes multiple detection periods.

[0178] Further, the difference between the vibration intensity value Adwm at each time in the current integration period and the vibration strengthening average value aAdwm in the last integration period is calculated to obtain a vibration strengthening processing value dAdwm.

[0179] Further, in the current integration period, the vibration strengthening processing value dAdwm is integrated to obtain a first integral value IdAdwm.

[0180] Further, in the current integration period, the absolute value of the vibration strengthening processing value dAdwm is taken and integrated to obtain a second integral value IabsdAdwm.

[0181] Further, the difference between the second integral value IabsdAdwm and the first integral value IdAdwm is calculated to obtain an integral difference value dIdAdwm, specifically, dIdAdwm = IabsdAdwm - IdAdwm.

[0182] Further, it is determined whether the integral difference value dIdAdwm is greater than a preset second threshold THdIdAdwm; if greater, it is determined that the trailer is swinging, otherwise, it is determined that the trailer is not swinging.

[0183] Optionally, in a possible implementation, the first determining module 33 is specifically used for:

[0184] performing first-order low-pass filtering on the yaw rate difference value signal to obtain a first filtered signal;

[0185] performing second-order Butterworth filtering on the first filtered signal to obtain a second filtered signal;

[0186] calculating a difference between a maximum value and a minimum value of the second filtered signal in each steady-state evaluation period to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period includes a plurality of steady-state evaluation periods;

[0187] determining whether the steady-state swing amplitude is greater than a preset sixth threshold; if greater, it is determined that the trailer is swinging, otherwise, it is determined that the trailer is not swinging.

[0188] In combination Figure 3 , the second determining module 34 is used to determine whether the driver has taken measures to eliminate or reduce the swing if the trailer is swinging.

[0189] In actual application, after it is determined that the trailer is swinging, the next step is to determine whether the driver has taken measures to eliminate or reduce the swing. The purpose of this step is to determine whether the trailer swing detection and control device needs to intervene and how to intervene to ensure the stability and safety of the vehicle.

[0190] It can be understood that the second determining module 34 is to ensure that the trailer swing detection and control device does not conflict with the operation of the driver, and can provide appropriate assistance when necessary to improve the maneuverability and safety of the vehicle. By intelligently determining the intention and operation of the driver, the trailer swing detection and control device can more effectively manage the dynamic behavior of the vehicle, especially in complex vehicle operation systems.

[0191] As an example, in a possible implementation, the second determining module 34 is specifically used for:

[0192] obtaining a current brake pedal opening degree of the towing vehicle and a current steering wheel angle.

[0193] If the current brake pedal opening degree is greater than a preset fourth threshold, and the current steering wheel angle is greater than a preset fifth threshold, it is determined that the driver has taken measures to eliminate the swing, otherwise, it is determined that the driver has not taken measures to eliminate the swing.

[0194] In practical applications, the fourth threshold value and the fifth threshold value can be preset according to historical data or experimental data of the vehicle running system. It can be understood that, when the current brake pedal opening is greater than the preset fourth threshold value THb and the current steering wheel angle is greater than the preset fifth threshold value THs, it indicates that the driver has taken the roll damping measure, and at this time, the system does not actively trigger the roll damping control, and the response to the driver input is given priority.

[0195] In combination Figure 3 The control module 35 is configured to, if the driver does not take the roll damping measure, perform brake intervention control to stop the trailer from rolling; wherein the brake intervention control comprises: reducing the engine torque value of the towing vehicle according to a predetermined change rate; and applying brake pressure to each axle of the trailer, the front axle of the towing vehicle and the rear axle of the towing vehicle according to a preset fixed ratio to reduce the longitudinal acceleration of the vehicle running system.

[0196] Specifically, the torque output of the engine of the towing vehicle is reduced according to a predetermined change rate, which can reduce the driving force of the vehicle and thus reduce the instability caused by the trailer rolling. In practical applications, the change rate of the torque reduction can be calibrated according to the test results of the actual vehicle to ensure the control effect while avoiding excessive impact on the driving performance of the vehicle.

[0197] Specifically, brake pressure is applied to each axle of the trailer and the front axle and the rear axle of the towing vehicle, and the brake pressure is applied according to a preset fixed ratio. The ratio can be determined according to the brake pressure distribution ratio when the brake system is designed, for example, the brake pressure is applied to each axle of the trailer and the front axle and the rear axle of the towing vehicle according to a ratio of 1:1:1. The purpose of applying brake pressure is to generate longitudinal deceleration to help reduce the speed of the vehicle and further suppress the rolling of the trailer.

[0198] It can be understood that, through the brake intervention control, the longitudinal acceleration ax of the vehicle running system, i.e. the acceleration in the forward direction of the vehicle, can be reduced, so that the speed of the vehicle is reduced to prevent the risk caused by further aggravation of the rolling.

[0199] In this embodiment, the motion state data of the towing vehicle measured by the existing electronic stability control sensor is acquired by the acquisition module 31, and the yaw rate difference signal is calculated by the calculation module 32. According to the yaw rate difference signal, the abnormal rolling of the trailer can be found in time, so that corresponding control measures can be taken to save the cost of trailer rolling detection and control. Further, when the rolling of the trailer is detected and the driver does not take the roll damping measure, the brake intervention control is timely and effectively performed by the control module 35 to realize timely and effective control of the rolling of the trailer, and the stability and safety of the vehicle system are improved. As can be seen from the above, the scheme of this embodiment saves the cost of trailer rolling detection and control while improving the stability and safety of the vehicle system.

[0200] In addition, when the value of dIdAdwm is further increased, and is greater than a preset third threshold THdIdAdwm2, the pressure of the front and rear wheels outside the swing direction of the main vehicle (towing vehicle) corresponding to the current yaw rate w can be slightly greater than that of the inner side wheels, that is, the pressure dP of the outer side wheels is additionally increased, so as to correct the possible over-steering situation and better stabilize the vehicle posture in the case of large amplitude swing. The specific value of dP can be determined according to experience or real vehicle test calibration.

[0201] Optionally, in a possible implementation, the device further includes:

[0202] The processing module is configured to determine whether the integral difference value is greater than a preset third threshold, and if so, increase the pressure of the outer front wheels of the towing vehicle; wherein the third threshold is greater than the second threshold.

[0203] In this embodiment, when the integral difference value of the yaw rate difference signal dIdAdwm exceeds the preset third threshold THdIdAd2, the additional pressure dP is applied to the outer wheels of the towing vehicle, which can more effectively suppress the swing of the trailer and enhance the stability of the vehicle.

[0204] The trailer swing detection and control device provided in the embodiment obtains the motion state data of the towing vehicle measured by the existing electronic stability control sensor through the acquisition module, and calculates the yaw rate difference signal through the calculation module. According to the yaw rate difference signal, the abnormal swing of the trailer can be found in time, so that corresponding control measures can be taken, thereby saving the cost of trailer swing detection and control. Further, when the swing of the trailer is detected and the driver does not take swing measures, the control module timely and effectively performs brake intervention control, so as to realize timely and effective control of the swing of the trailer and improve the stability and safety of the vehicle system. As can be seen from the above, the scheme of the embodiment saves the cost of trailer swing detection and control while improving the stability and safety of the vehicle system.

[0205] Figure 4 is a structural schematic diagram of an electronic device provided by the present application, as Figure 4As shown, the electronic device can include a processor 410, a communications interface 420, a memory 430, and a communications bus 440, wherein the processor 410, the communications interface 420, and the memory 430 complete mutual communication through the communications bus 440. The processor 410 can invoke a logic instruction in the memory 430 to execute a trailer swing detection and control method, which includes: obtaining motion state data of the towing vehicle in the current detection period measured by an electronic stability control sensor, and calculating a yaw rate difference signal based on the motion state data of the towing vehicle in the current detection period; wherein the motion state data of the towing vehicle includes: a steering wheel angle of the towing vehicle, a vehicle speed of the towing vehicle, a front wheel angle of the towing vehicle, an axle distance of the towing vehicle, a characteristic vehicle speed of the towing vehicle, and an actual yaw rate of the towing vehicle; determining whether the trailer swings according to the yaw rate difference signal; if the trailer swings, determining whether the driver has taken swing mitigation measures; if the driver has not taken swing mitigation measures, performing brake intervention control to stop the trailer from swinging; wherein the brake intervention control includes: reducing the engine torque value of the towing vehicle according to a predetermined change rate; and applying brake pressure to each axle of the trailer, the front axle of the towing vehicle, and the rear axle of the towing vehicle according to a preset fixed ratio to reduce the longitudinal acceleration of the vehicle running system.

[0206] In addition, the logic instruction in the memory 430 described above can be implemented in the form of a software function unit and sold or used as an independent product, which can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various program code storage media.

[0207] In another aspect, the present application also provides a computer program product, which comprises a computer program stored on a non-transitory computer readable storage medium, and the computer program is executable by a processor to cause a computer to perform the trailer swing detection and control method provided by any of the above methods, which comprises: obtaining motion state data of the towing vehicle in a current detection period measured by an electronic stability control sensor, and calculating a yaw rate difference signal based on the motion state data of the towing vehicle in the current detection period; wherein the motion state data of the towing vehicle comprises: a steering wheel angle of the towing vehicle, a vehicle speed of the towing vehicle, a front wheel angle of the towing vehicle, a wheelbase of the towing vehicle, a characteristic vehicle speed of the towing vehicle, and an actual yaw rate of the towing vehicle; determining whether the trailer swings according to the yaw rate difference signal; if the trailer swings, determining whether the driver has taken swing elimination measures; if the driver has not taken swing elimination measures, performing brake intervention control to stop the trailer from swinging; wherein the brake intervention control comprises: reducing the engine torque value of the towing vehicle at a predetermined change rate; and applying brake pressure to each axle of the trailer, the front axle of the towing vehicle, and the rear axle of the towing vehicle at a preset fixed ratio to reduce the longitudinal acceleration of the vehicle running system.

[0208] In another aspect, the present application also provides a non-transitory computer readable storage medium having a computer program stored thereon, and the computer program is executable by a processor to implement the trailer swing detection and control method provided by any of the above methods, which comprises: obtaining motion state data of the towing vehicle in a current detection period measured by an electronic stability control sensor, and calculating a yaw rate difference signal based on the motion state data of the towing vehicle in the current detection period; wherein the motion state data of the towing vehicle comprises: a steering wheel angle of the towing vehicle, a vehicle speed of the towing vehicle, a front wheel angle of the towing vehicle, a wheelbase of the towing vehicle, a characteristic vehicle speed of the towing vehicle, and an actual yaw rate of the towing vehicle; determining whether the trailer swings according to the yaw rate difference signal; if the trailer swings, determining whether the driver has taken swing elimination measures; if the driver has not taken swing elimination measures, performing brake intervention control to stop the trailer from swinging; wherein the brake intervention control comprises: reducing the engine torque value of the towing vehicle at a predetermined change rate; and applying brake pressure to each axle of the trailer, the front axle of the towing vehicle, and the rear axle of the towing vehicle at a preset fixed ratio to reduce the longitudinal acceleration of the vehicle running system.

[0209] The device embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed to multiple network units. Part or all of the modules can be selected to achieve the purposes of the embodiments according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0210] Through the description of the above embodiments, those skilled in the art can clearly understand that the embodiments can be realized by means of software and the necessary general hardware platform, and of course can also be realized by hardware. Based on such understanding, the above technical solutions can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0211] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A trailer sway detection and control method, characterized by, The application is applied to a vehicle operation system, which comprises a tractor, a trailer, a trailer swing detection and control device and an electronic stability control sensor arranged on the tractor; the method comprises: The trailer swing detection and control device acquires motion state data of the tractor in a current detection period measured by the electronic stability control sensor, and calculates a yaw rate difference signal based on the motion state data of the tractor in the current detection period; wherein the motion state data of the tractor comprises a steering wheel angle of the tractor, a vehicle speed of the tractor, a front wheel angle of the tractor, a wheelbase of the tractor, a characteristic vehicle speed of the tractor and an actual yaw rate of the tractor; The trailer swing detection and control device judges whether the trailer swings according to the yaw rate difference signal; The trailer swing detection and control device judges whether the trailer swings according to the yaw rate difference signal, which comprises that the trailer swing detection and control device performs first-order low-pass filtering on the yaw rate difference signal to obtain a first filtered signal; the trailer swing detection and control device performs second-order Butterworth filtering on the first filtered signal to obtain a second filtered signal; the trailer swing detection and control device calculates a difference between a maximum value and a minimum value of the second filtered signal in each steady-state evaluation period to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period comprises a plurality of steady-state evaluation periods; the trailer swing detection and control device takes a maximum value of the steady-state swing amplitude in the current detection period as a vibration intensity value in the current detection period; the trailer swing detection and control device calculates an average value of the vibration intensity value in a current integration period to obtain a vibration reinforcement average value; wherein the integration period comprises a plurality of detection periods; the trailer swing detection and control device calculates a difference between a vibration intensity value at each time point in the current integration period and the vibration reinforcement average value in the last integration period to obtain a vibration reinforcement processing value; the trailer swing detection and control device integrates the vibration reinforcement processing value in the current integration period to obtain a first integral value; In the current integration period, the trailer swing detection and control device takes an absolute value of the vibration reinforcement processing value and integrates it to obtain a second integral value; the trailer swing detection and control device calculates a difference between the second integral value and the first integral value to obtain an integral difference value; the trailer swing detection and control device judges whether the integral difference value is greater than a preset second threshold value; if yes, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing; If the trailer swings, the trailer swing detection and control device judges whether the driver has taken swing measures; If the trailer swings, the trailer swing detection and control device judges whether the driver has taken swing measures; If the driver does not take the countermeasure, the trailer swing detection and control device performs brake intervention control to stop the trailer from swinging; wherein the brake intervention control comprises: reducing the engine torque value of the tractor according to a predetermined change rate; applying brake pressure to each axle of the trailer, the front axle of the tractor and the rear axle of the tractor according to a preset fixed ratio to reduce the longitudinal acceleration of the vehicle operation system.

2. The trailer swing detection and control method of claim 1, wherein, The calculation of the yaw rate difference signal based on the motion state data of the tractor in the current detection period comprises: The trailer swing detection and control device calculates the target yaw rate of each time point in the current detection period based on the steering wheel angle of the tractor, the vehicle speed of the tractor, the front wheel angle of the tractor, the wheelbase of the tractor and the characteristic vehicle speed of the tractor at each time point in the current detection period. The trailer swing detection and control device calculates the difference between the actual yaw rate and the target yaw rate at each time point in the current detection period to obtain the yaw rate difference signal.

3. The trailer sway detection and control method of claim 2, wherein, The trailer swing detection and control device judges whether the trailer swings according to the yaw rate difference signal, comprising: The trailer swing detection and control device performs system identification on the yaw rate difference signal to obtain the vibration amplitude of the yaw rate difference signal. If the vibration amplitude of the yaw rate difference signal is greater than a preset first threshold value, it is determined that the trailer swings, otherwise it is determined that the trailer does not swing.

4. The trailer sway detection and control method of claim 1, wherein, After the brake intervention control, the method further comprises: The trailer swing detection and control device judges whether the integral difference value is greater than a preset third threshold value, and if so, increases the pressure of the outer front wheel of the tractor; wherein the third threshold value is greater than the second threshold value.

5. The trailer sway detection and control method of any of claims 1-4, wherein, The trailer swing detection and control device judges whether the driver has taken the countermeasure, comprising: The trailer swing detection and control device obtains the current brake pedal opening and the current steering wheel angle of the tractor; If the current brake pedal opening is greater than a preset fourth threshold value and the current steering wheel angle is greater than a preset fifth threshold value, the trailer swing detection and control device determines that the driver has taken the countermeasure, otherwise it is determined that the driver has not taken the countermeasure.

6. A trailer sway detection and control apparatus characterized by, Applied to a vehicle operation system, the vehicle operation system comprises a tractor, a trailer, a trailer swing detection and control device and an electronic stability control sensor deployed on the tractor; the device comprises: An acquisition module for acquiring the motion state data of the tractor measured by the electronic stability control sensor in the current detection period; a calculation module, configured to calculate a yaw rate difference signal based on motion state data of the tractor in the current detection period; wherein the motion state data of the tractor comprises a steering wheel angle of the tractor, a vehicle speed of the tractor, a front wheel angle of the tractor, a wheelbase of the tractor, a characteristic vehicle speed of the tractor, and an actual yaw rate of the tractor; a first judgment module, configured to judge whether the trailer swings according to the yaw rate difference signal; wherein the first judgment module is specifically configured to: perform first-order low-pass filtering on the yaw rate difference signal by the trailer swing detection and control device to obtain a first filtered signal; perform second-order Butterworth filtering on the first filtered signal by the trailer swing detection and control device to obtain a second filtered signal; calculate a difference between a maximum value and a minimum value of the second filtered signal in each steady-state evaluation period by the trailer swing detection and control device to obtain a steady-state swing amplitude in each steady-state evaluation period; wherein the current detection period comprises a plurality of steady-state evaluation periods; take a maximum value of the steady-state swing amplitude in the current detection period as a vibration intensity value in the current detection period by the trailer swing detection and control device; calculate an average value of the vibration intensity value in the current integration period by the trailer swing detection and control device to obtain a vibration reinforcement average value; wherein the integration period comprises a plurality of detection periods; calculate a difference between the vibration intensity value at each time point in the current integration period and the vibration reinforcement average value in the last integration period by the trailer swing detection and control device to obtain a vibration reinforcement processing value; integrate the vibration reinforcement processing value in the current integration period by the trailer swing detection and control device to obtain a first integral value; take an absolute value of the vibration reinforcement processing value and integrate it in the current integration period by the trailer swing detection and control device to obtain a second integral value; calculate a difference between the second integral value and the first integral value by the trailer swing detection and control device to obtain an integral difference value; judge whether the integral difference value is greater than a preset second threshold value by the trailer swing detection and control device; if yes, it is determined that the trailer swings, otherwise, it is determined that the trailer does not swing; a second judgment module, configured to judge whether the driver has taken swing elimination measures if the trailer swings; a control module, configured to perform brake intervention control to stop the trailer from swinging if the driver has not taken swing elimination measures; wherein the brake intervention control comprises: reducing an engine torque value of the tractor at a predetermined change rate; applying brake pressure to each axle of the trailer, the front axle of the tractor, and the rear axle of the tractor at a preset fixed ratio to reduce the longitudinal acceleration of the vehicle operation system.

7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and running on the processor, characterized in that, The processor executes the computer program to realize the trailer swing detection and control method according to any one of claims 1 to 5.

8. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to realize the trailer swing detection and control method according to any one of claims 1 to 5.

9. A computer program product comprising a computer program, characterized in that, The computer program, when executed by a processor, implements the trailer swing detection and control method according to any one of claims 1 to 5.

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