Three-way load acquisition method and system of trailer coupler and passenger car

Abstract

The present application relates to the technical field of road load acquisition, and provides a three-way load acquisition method for a trailer coupler, which is as follows: detecting whether the trailer coupler structure is coupled, if the detection result is no, determining the load on the corresponding axial based on the real-time detected three-axis axial strain, and if the detection result is yes, first decoupling the real-time detected three-axis axial strain, and then determining the load on the corresponding axial. The present application first loads standard load on three axials in turn to obtain the strain matrix of the trailer coupler under the standard load, eliminates the coupling of the trailer coupler on the loads in X, Y and Z axises based on the strain matrix, modifies the trailer coupler into a force sensor unit capable of simultaneously measuring the loads in X, Y and Z axises, and realizes the acquisition of the road load spectrum.

Description

Technical Field

[0001] The present invention relates to the technical field of road load collection, and provides a three-directional load collection method and system for a trailer coupler, and a passenger car. Background Art

[0002] In the current development of passenger vehicles, more passenger car models are being developed to expand into overseas markets and meet the needs of foreign customers for towing different trailers. As an important accessory of the entire vehicle, the reliability of the trailer towing device is a key factor affecting the performance of the entire vehicle.

[0003] During trailer hitch development, the loads on the hitch and vehicle body are often estimated empirically based on the weight the hitch will be required to tow. The trailer coupler, the sole connection point between the hitch and the trailer, transmits all forces acting on the hitch and vehicle body. By analyzing the load on the trailer coupler, we can accurately assess the forces acting on the hitch and vehicle body.

[0004] Currently, due to the lack of payload data for trailer couplers, the force verification of the trailer towing device and vehicle body is insufficient, posing reliability risks. Summary of the Invention

[0005] In view of this, the present application provides a three-directional load collection method and system for a trailer coupler and a passenger car, which realizes load collection of a passenger car trailer coupler in the X-axis, Y-axis and Z-axis directions.

[0006] Specifically, the following technical solutions are included:

[0007] In one aspect, an embodiment of the present application provides a three-way load collection method for a trailer coupler, the method being as follows:

[0008] Detect whether the trailer coupler structure is coupled. If the detection result is no, determine the corresponding axial load based on the three-axis axial strain detected in real time. If the detection result is yes, first decouple the three-axis axial strain detected in real time, and then determine the corresponding axial load.

[0009] In some embodiments, the relationship coefficient k between the strain in the X-axis, Y-axis, and Z-axis and the load is x , relationship coefficient k y and the relationship coefficient k z , to calculate the loads in the X-axis, Y-axis and Z-axis.

[0010] In some embodiments, the relationship coefficient k x , relationship coefficient k y and the relationship coefficient kz The method to obtain is as follows:

[0011] When the trailer coupling structure is coupled, the relationship coefficient k between the strain in the X-axis, Y-axis and Z-axis after decoupling and the load is calibrated. x , relationship coefficient k y and the relationship coefficient k z ;

[0012] When the trailer coupling structure is not coupled, the relationship coefficient k between the strain and load when the X-axis, Y-axis and Z-axis are not coupled is calibrated x , relationship coefficient k y and the relationship coefficient k z .

[0013] In some embodiments, the coupling determination method of the trailer coupler structure is as follows:

[0014] If the X-axis is uncoupled, the Y-axis is uncoupled, and the Z-axis is uncoupled, the trailer coupler structure is deemed to be uncoupled; otherwise, the trailer coupler structure is deemed to be coupled.

[0015] In some embodiments, the axial coupling determination method is specifically as follows:

[0016] Standard load for X-axis loading When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously xx 、s xy 、s xz ; Load standard load in Y axis When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously yx 、s yy 、s yz ; Load standard load in Z axis When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously zx 、s zy 、s zz ;

[0017] If the non-diagonal elements s yx 、s zx With diagonal elements s xx If the ratio of is less than the set ratio, it is considered that the X axis is not coupled, otherwise it is considered that the X axis is coupled; if the non-diagonal element s xy 、s zy With diagonal elements s yy If the ratio of the non-diagonal element s is less than the set ratio, it is considered that the Y axis is not coupled, otherwise it is considered that the Y axis is coupled; if the non-diagonal element s xz 、s yz With diagonal elements s zzIf the ratio of the strain value of the X-axis to the ratio of the strain value of the Y-axis and the ratio of the strain value of the Z-axis are all less than the set ratio, it is determined that the Z-axis is not coupled, otherwise it is determined that the Z-axis is coupled.

[0018] In some embodiments, in the case that the trailer coupler structure is not coupled, the relationship coefficient k of each axis is equal to the ratio of the standard load of the corresponding axis to the strain value of the corresponding axis; in the case that the trailer coupler structure is coupled, the strain value matrix S is first decoupled to obtain the decoupled strain matrix S', and the relationship coefficient k of each axis is equal to the ratio of the standard load of the corresponding axis to the decoupled strain value of the corresponding axis.

[0019] In another aspect, the embodiments of the present application also provide a three-dimensional load acquisition device of a trailer coupler, the device comprising:

[0020] The first strain gauge full bridge, the second strain gauge full bridge and the third strain gauge full bridge arranged at the load sensitive part of the trailer coupler are respectively used for acquiring the bending strain value of the X-axis, the bending strain value of the Y-axis and the tensile and compressive strain value of the Z-axis;

[0021] The processor connected with the first strain gauge full bridge, the second strain gauge full bridge and the third strain gauge full bridge determines the load of the X-axis, the Y-axis and the Z-axis based on the above-mentioned three-dimensional load acquisition method of the trailer coupler.

[0022] In some embodiments, the load sensitive part of the trailer coupler is the neck part of the ball head.

[0023] In another aspect, the embodiments of the present application also provide a passenger car, the head of the passenger car is fixedly connected with the fixed part of the trailer coupler, and the trailer coupler is integrated with the above-mentioned three-dimensional load acquisition device of the trailer coupler.

[0024] The present application first loads the standard load on the three axes in sequence, acquires the strain matrix of the trailer coupler under the standard load, eliminates the coupling of the trailer coupler in the X-axis, the Y-axis and the Z-axis based on the strain matrix, modifies the trailer coupler into a force sensor unit capable of simultaneously measuring the load in the X-axis, the Y-axis and the Z-axis, and realizes the acquisition of the road load spectrum. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0026] Figure 1 The structural schematic diagram of the three-dimensional load acquisition device of the trailer coupler provided by the embodiments of the present application;

[0027] Figure 2 A flow chart of a three-way load collection method for a trailer coupler provided in an embodiment of the present invention;

[0028] Figure 3 A diagram showing the distribution of strain gauges on the ball neck provided by an embodiment of the present invention;

[0029] Figure 4 A schematic diagram of the arrangement of the first parallel strain gauges provided in an embodiment of the present invention;

[0030] Figure 5 A schematic diagram of the arrangement of the second parallel strain gauges provided in an embodiment of the present invention;

[0031] Figure 6 A schematic diagram of the arrangement of T-shaped strain gauges provided in an embodiment of the present invention;

[0032] The reference numerals in the figures represent respectively:

[0033] 1. Fixed part, 2. Elastic part, 3. Ball neck, 4. Ball head;

[0034] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0036] Unless otherwise defined, all technical terms used in the embodiments of the present application have the same meanings as commonly understood by those skilled in the art.

[0037] In order to make the technical solutions and advantages of the present application clearer, the implementation methods of the present application will be described in further detail below with reference to the accompanying drawings.

[0038] In order to improve the problems existing in the related art, realize the payload data acquisition of the trailer coupler, the embodiment of the application provides a trailer coupler three-way load acquisition device, the trailer coupler comprising: a fixed part 1 used for fixed connection with a passenger car, the fixed part 1 being connected with a ball head 4 through an elastic part 2, the ball head 4 being used for connecting other vehicles, the ball head 4 being connected with the elastic part 2 through a connecting part 3, the connecting part 3 being a ball head neck part in the application, through CAE analysis, the ball head neck part is the most sensitive part to the load in the whole trailer coupler structure, therefore, the trailer coupler three-way load acquisition device is arranged at the neck part of the ball head, the three-way in the application is the X-axis direction, the Y-axis direction and the Z-axis direction of the passenger car coordinate system, wherein the passenger car coordinate system is that a user stands facing the car head, according to the right hand rule, the direction of the thumb is the Z-axis direction, the direction of the index finger is the X-axis direction, and the direction of the middle finger is the Y-axis direction.

[0039] The structural schematic diagram of the trailer coupler three-way load acquisition device is as shown in Figure 1 , for the convenience of description, only parts related to the embodiment of the application are shown, and the device comprises:

[0040] Two first parallel strain gauges are arranged along the X-axis radial direction, see P1 in Figure 4 , each first parallel strain gauge is composed of two single pieces, two first parallel strain gauges form a first strain gauge full bridge (referred to as a first full bridge), and the first full bridge is used for acquiring the bending strain s x X of the X-axis direction.

[0041] Two second parallel strain gauges are arranged along the Y-axis radial direction, see P2 in Figure 5 , each second parallel strain gauge is composed of two single pieces, two second parallel strain gauges form a second strain gauge full bridge (referred to as a second full bridge), and the second full bridge is used for acquiring the bending strain s y Y of the Y-axis direction.

[0042] Two T-shaped strain gauges are arranged along the Z-axis radial direction, see P3 in Figure 6 , each T-shaped strain gauge is composed of two single pieces, two T-shaped strain gauges form a third strain gauge full bridge (referred to as a third full bridge), and the third full bridge is used for acquiring the tensile and compressive strain s z Z of the Z-axis direction, the projections of the T-shaped strain gauges in the X-Y plane are located in the middle of the first parallel strain gauge and the second parallel strain gauge, as shown in Figure 3 .

[0043] The first full bridge, the second full bridge and the third full bridge are connected with a processor, the first full bridge, the second full bridge and the third full bridge send the acquired strain to the processor, and the processor determines the load of the trailer coupler on the X-axis, the Y-axis and the Z-axis based on the following method.

[0044] The application analyzes the structure of the trailer coupler, finds the most sensitive part of the trailer coupler to the X-axis, Y-axis and Z-axis three-direction load, realizes the induction of the tensile and compressive strain and the bending strain of the trailer coupler by pasting different types of strain gauges at the load sensitive parts and forming a bridge way of the strain gauges, and provides data support for the following three-direction load collection of the trailer coupler.

[0045] Figure 2 The method flow chart of the three-direction load collection of the trailer coupler provided by the embodiment of the application is as follows:

[0046] If the detection result is no, the load on the corresponding axis is determined based on the real-time detected three-axis axial strain; if the detection result is yes, the real-time detected three-axis axial strain is decoupled first, and then the load on the corresponding axis is determined.

[0047] Specifically, if the trailer coupler structure itself is not coupled, that is, when a load is applied to the X-axis, only the bending strain variable is generated in the X-axis, and no bending strain variable and tensile and compressive strain variables are generated in the Y-axis and Z-axis, that is, when a load is applied to the X-axis, no interference is generated on the Y-axis and Z-axis, and similarly, when a load is applied to the Y-axis, only the bending strain variable is generated in the Y-axis, and no bending strain variable and tensile and compressive strain variables are generated in the X-axis and Z-axis, and when a load is applied to the Z-axis, only the bending strain variable is generated in the Z-axis, and no bending strain variable is generated in the X-axis and Y-axis, and vice versa, then the trailer coupler structure itself is coupled.

[0048] When the trailer coupler structure itself is not coupled, the bending strain variable s x The load F x on the X-axis is directly calculated based on the currently detected bending strain variable s y The load F y on the Y-axis is directly calculated based on the currently detected bending strain variable s z The load F z on the Z-axis is directly calculated based on the currently detected tensile and compressive strain variable s .

[0049] When the trailer coupler structure itself is coupled, the currently detected bending strain variable s x , the currently detected bending strain variable s y and the currently detected bending strain variable s z need to be decoupled to obtain the decoupled bending strain variable s' x , the bending strain variable s' y and the tensile and compressive strain variable s' z , and then the load F x on the X-axis, the load F yAnd the Z-axis load F z .

[0050] In the embodiment of the present invention, the relationship coefficient k between the bending strain and the load when decoupled or uncoupled is calibrated for the X-axis, Y-axis, and Z-axis, respectively. x , relationship coefficient k y and the relationship coefficient k z .

[0051] In the embodiment of the present invention, the above relationship coefficient k x , relationship coefficient k y and the relationship coefficient k z The calibration method is as follows:

[0052] Use standard force sensors to apply standard loads to the three axes and apply standard loads to the X axis. When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously xx 、s xy 、s xz ; Load standard load in Y axis When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously yx 、s yy 、s yz ; Load standard load in Z axis When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously zx 、s zy 、s zz By calibrating the loading load and strain response, a third-order matrix can be formed. The matrix expression relationship is as follows:

[0053]

[0054] In order to more accurately test the strain in the X-axis, Y-axis, and Z-axis under each standard load, the embodiment of the present invention loads the standard load on the X-axis multiple times. Corresponding to multiple collections of strains in the X-axis, Y-axis, and Z-axis directions, the mean of the strain in the X-axis direction, the mean of the strain in the Y-axis direction, and the mean of the strain in the Z-axis direction is the strain variable s xx 、s xy 、s xz ; Similarly, obtain the dependent variable s yx 、s yy 、s yz , the dependent variable s zx 、s zy 、s zz , the dependent variable s xx 、s xy 、s xz ; Dependent variable s yx 、syy 、s yz , the dependent variable s zx 、s zy 、s zz Form the dependent variable matrix S.

[0055] In the embodiment of the present invention, the coupling conditions in the X-axis, Y-axis, and Z-axis directions are determined based on the off-diagonal element values ​​in the strain matrix S. For the X-axis direction, if the off-diagonal element s yx 、s zx With diagonal elements s xx If the ratio of is less than the set ratio, it is considered that the X-axis is not coupled, otherwise it is considered that the X-axis is coupled; for the Y-axis, if the non-diagonal element s xy 、s zy With diagonal elements s yy If the ratio of is less than the set ratio, it is considered that the Y axis is not coupled, otherwise it is considered that the Y axis is coupled; for the Z axis, if the non-diagonal element s xz 、s yz With diagonal elements s zz If the ratios of are all less than the set ratio, it is considered that the Z axis is not coupled, otherwise it is considered that the Z axis is coupled. The above set ratio can be set according to the required load accuracy. The higher the required load accuracy, the smaller the set ratio value. Usually, the value is 5%.

[0056] If the X-axis is uncoupled, the Y-axis is uncoupled, and the Z-axis is uncoupled, the trailer coupling structure is deemed uncoupled. Otherwise, the trailer coupling structure is deemed coupled. When the trailer coupling structure is uncoupled, the relationship coefficient k of each axis is equal to the ratio of the standard load of the corresponding axial load to the strain of the corresponding axial direction, that is, the relationship coefficient Relationship coefficient Relationship coefficient In the case of trailer coupling structure coupling, the strain matrix S needs to be decoupled first. The decoupling process of the strain matrix S is to first obtain the inverse matrix S of the strain matrix S. -1 , then the strain matrix after decoupling S′=S -1 *S, the relationship coefficient k of each axial direction is equal to the ratio of the standard load of the corresponding axial loading to the decoupling strain of the corresponding axial direction, that is, the relationship coefficient Relationship coefficient Relationship coefficient Among them, s′ xx , s′ yy 、s z ' z are the diagonal elements in the strain matrix S′.

[0057] The present invention first obtains the strain matrix of the trailer coupler under the standard load by sequentially applying standard loads to the three axial directions. Based on the strain matrix, the coupling of the trailer coupler in the loads in the three directions of X-axis, Y-axis and Z-axis is eliminated, and the trailer coupler is converted into a force sensor unit that can simultaneously measure the loads in the three directions of X-axis, Y-axis and Z-axis, thereby realizing the collection of the road load spectrum.

[0058] The present invention also provides a passenger vehicle, wherein the front end of the passenger vehicle is fixedly connected to the fixed portion of a trailer coupler. The trailer coupler is provided with the above-mentioned trailer coupler three-dimensional load collection device, which includes at least a first strain gauge full bridge, a second strain gauge full bridge, and a third strain gauge full bridge disposed at a load-sensitive portion of the trailer coupler, and a processor connected to the first, second, and third strain gauge full bridges. The first, second, and third strain gauge full bridges collect bending strain in the X and Y axes, and tensile and compressive strain in the Z direction, and transmit these to the processor, which then calculates the loads in the X, Y, and Z directions. Since the passenger vehicle is integrated with the trailer coupler three-dimensional load collection device for detecting three-dimensional loads, the device can be used to measure the three-dimensional loads of the passenger vehicle in real time under various road conditions.

[0059] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more than two, unless expressly limited otherwise.

[0060] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the present invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only.

[0061] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for collecting three-dimensional load of a trailer coupler, characterized in that: The method is specifically as follows: Detecting whether the trailer coupling structure is coupled. If the detection result is no, determining the corresponding axial load based on the three-axis axial strain detected in real time. If the detection result is yes, first decoupling the three-axis axial strain detected in real time, and then determining the corresponding axial load; The coupling determination method of the trailer coupler structure is as follows: If the X-axis is uncoupled, the Y-axis is uncoupled, and the Z-axis is uncoupled, the trailer coupler structure is deemed uncoupled; otherwise, the trailer coupler structure is deemed coupled; The axial coupling determination method is as follows: Standard load for X-axis loading When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously xx 、s xy 、s xz ; Load standard load in Y axis When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously yx 、s yy 、s yz ; Load standard load in Z axis When the strain values ​​s in the X-axis, Y-axis and Z-axis directions are collected simultaneously zx 、s zy 、s zz ; If the non-diagonal elements s yx 、s zx With diagonal elements s xx If the ratio of is less than the set ratio, it is considered that the X axis is not coupled, otherwise it is considered that the X axis is coupled; if the non-diagonal element s xy 、s zy With diagonal elements s yy If the ratio of the non-diagonal element s is less than the set ratio, it is considered that the Y axis is not coupled, otherwise it is considered that the Y axis is coupled; if the non-diagonal element s xz 、s yz With diagonal elements s zz If the ratios of are all less than the set ratio, it is considered that the Z axis is not coupled, otherwise it is considered that the Z axis is coupled.

2. The method for collecting three-dimensional load of a trailer coupler according to claim 1, characterized in that: The relationship coefficient k between the strain in the X-axis, Y-axis, and Z-axis and the load x , relationship coefficient k y and the relationship coefficient k z , to calculate the loads in the X-axis, Y-axis and Z-axis.

3. The method for collecting three-dimensional load of a trailer coupler according to claim 1, characterized in that: Relationship coefficient k x , relationship coefficient k y and the relationship coefficient k z The method to obtain is as follows: When the trailer coupling structure is coupled, the relationship coefficient k between the strain in the X-axis, Y-axis and Z-axis after decoupling and the load is calibrated. x , relationship coefficient k y and the relationship coefficient k z ; When the trailer coupling structure is not coupled, the relationship coefficient k between the strain and load when the X-axis, Y-axis and Z-axis are not coupled is calibrated x , relationship coefficient k y and the relationship coefficient k z .

4. The method for collecting three-dimensional load of a trailer coupler according to claim 2 or 3, characterized in that: When the trailer coupling structure is uncoupled, the relationship coefficient k of each axial direction is equal to the ratio of the standard load of the corresponding axial loading to the strain of the corresponding axial direction; when the trailer coupling structure is coupled, the strain matrix S is first decoupled to obtain the decoupled strain matrix S′, and the relationship coefficient k of each axial direction is equal to the ratio of the standard load of the corresponding axial loading to the decoupled strain of the corresponding axial direction.

5. A three-way load collection device for a trailer coupler, characterized in that: The device comprises: The first strain gauge full bridge, the second strain gauge full bridge, and the third strain gauge full bridge installed at the load-sensitive part of the trailer coupler are used to collect the bending strain in the X-axis and Y-axis directions, and the tensile and compressive strain in the Z direction, respectively. A processor connected to the first strain gauge full bridge, the second strain gauge full bridge, and the third strain gauge full bridge, the processor determining the loads in the X-axis, Y-axis, and Z-axis directions based on the three-axis load collection method for the trailer coupler according to any one of claims 1 to 4.

6. The three-way load collection device for a trailer coupler according to claim 5, characterized in that: The load-sensitive part of the trailer coupling is the ball neck.

7. A passenger car, characterized in that: The head of the passenger car is fixedly connected to the fixing portion of the trailer coupler, and the trailer coupler is integrated with the three-directional load collection device of the trailer coupler as claimed in claim 5 or 6.

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