Method, system and device for testing bearing capacity of automobile luggage rack and storage medium

Abstract

The invention discloses an automobile luggage rack bearing capacity testing method, system and device and a storage medium, and mainly relates to the technical field of automobile exterior trimming part testing. Comprising the following steps: determining the shape of the automobile luggage rack; setting a bearing capacity target, and defining a structural form; determining the positioning and mounting mode of the luggage rack; carrying out typical section design according to the style of the luggage rack; formulating a luggage rack test condition according to the use scene; through a static load test, a fixed tool on the luggage rack simulates a test working condition, and whether design requirements are met or not is judged; through a dynamic load test, a load is applied to the whole vehicle to carry out a road test, and whether design requirements are met or not is judged through stress performance of the luggage rack under different working conditions. The method has the beneficial effects that through simulation analysis of nine working conditions of the luggage rack, the structure of the luggage rack is optimized, and meanwhile it is ensured that the bearing capacity of the luggage rack product meets the design requirement.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile exterior trim testing, and in particular to a method, system, device and storage medium for testing the bearing capacity of an automobile luggage rack. Background Art

[0002] Since the luggage rack is made of aluminum profile, the process is an integrated extrusion and injection molding process. The process and design requirements for the manufacturer are relatively high. If the designer's own ability is insufficient and only relies on experience, the manufactured product cannot meet the load-bearing function required by the customer, resulting in a waste of time and molds. Another problem is that the current customer demand is high, and there are more luggage during travel, which requires a higher load-bearing capacity of the luggage rack. Excessive load of objects will cause the roof luggage rack to deform. Therefore, the design method of the luggage rack requires not only beauty but also practicality.

[0003] In the existing scheme, the designer designed a product with weak bearing capacity based on his own experience without CAE analysis. Without verifying the 9 working conditions through static load test, it is impossible to determine the bearing capacity performance of the luggage rack during the stationary process. Considering the design cycle and cost, it is impossible to determine the attenuation of the luggage rack installation torque and the deformation of the luggage rack assembly in the height direction without dynamic load test.

[0004] Therefore, there is an urgent need for a vehicle luggage rack load-bearing capacity testing method, system, device and storage medium to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method, system, device and storage medium for testing the load-bearing capacity of a car luggage rack. Through simulation analysis of 9 working conditions of the luggage rack, the structure of the luggage rack is optimized. The bench test verifies the reliability of the static load. The dynamic load test examines the deformation and bolt tightening force of the luggage rack under different environments. The three methods are used in combination to ensure that the load-bearing capacity of the luggage rack product meets the design requirements.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] On the one hand, a method for testing the bearing capacity of a luggage rack of an automobile is provided, comprising the following steps:

[0008] S1: Determine the shape of the car luggage rack and select a roof-mounted or detached luggage rack according to the shape;

[0009] S2: Set the load-bearing capacity target, define the structural form, and determine whether the luggage rack should be split or integrated;

[0010] S3: Determine the location and installation method of the luggage rack, whether to select the bolt and rivet nut form, and the number of the installation points varies according to the form of the luggage rack;

[0011] S4: Design a typical section according to the style of the luggage rack, specifically:

[0012] If the bearing capacity is high, the base is made of aluminum alloy die casting;

[0013] If the bearing capacity is not high, use a plastic base;

[0014] S5: Formulate the luggage rack test conditions according to the usage scenarios, specifically, simulate the load-bearing capacity analysis through CAE simulation;

[0015] S6: Through static load test, the fixture on the luggage rack simulates the test conditions to determine whether it meets the design requirements;

[0016] S7: Through dynamic load test, load is added to the whole vehicle for road test, and the stress performance of the luggage rack under different working conditions is judged to determine whether it meets the design requirements.

[0017] Preferably, in step S5, the CAE simulation analysis specifically includes the following steps:

[0018] S51: Determine the material of the luggage rack body and the connection method between the luggage rack and the vehicle body, wherein the connection method between the luggage rack and the vehicle body is specifically: connected via a bracket;

[0019] S52: Determine the luggage rack displacement, and the stress distribution of the luggage rack and the bracket under several static load conditions;

[0020] S53: Establish a finite element model of the luggage rack according to steps S51-S52.

[0021] Preferably, the luggage rack finite element model specifically includes luggage rack displacement analysis, luggage rack stress analysis and luggage rack bracket stress analysis.

[0022] Preferably, in the simulation analysis, the luggage rack displacement and the stress distribution of the luggage rack and the bracket are analyzed under 9 static load conditions. According to the design requirements, the maximum displacement of the luggage rack is less than 3 mm. The finite element of the luggage rack is simulated by 3D units with an average unit size of 10 mm. The cross section of the luggage rack crossbar is a solid circle with a diameter of 60 mm, which is connected to the luggage rack through rigid units.

[0023] Preferably, the luggage rack stress analysis is specifically as follows: through simulation analysis, under 9 working conditions, the maximum stress of the luggage rack is less than 120 MPa, which meets the yield strength of the material.

[0024] Preferably, the dynamic load test is specifically as follows: adding a load to the whole vehicle to directly examine the load performance and durability of the luggage rack under actual working conditions, installing a cross bar fixed with tooling on the luggage rack, and adding heavy objects to the cross bar for load testing.

[0025] Preferably, the method of the static load test in step S6 is:

[0026] The static load test model of the luggage rack is two luggage racks fixed on the tooling, and the relative position of the luggage racks is consistent with the actual vehicle;

[0027] The distance between the two crossbars is 700mm, and the square weights are 1000mm long and 600mm wide, and are securely fixed on the luggage rack.

[0028] The crossbeam installation meets the load-bearing requirements. The luggage rack can bear 50KG (including the auxiliary load-bearing crossbeam). After testing under nine different working conditions, the maximum deformation of the luggage rack is less than 3mm.

[0029] On the other hand, a testing system based on the above-mentioned vehicle luggage rack load-bearing capacity testing method is provided, which is used to implement the method steps in any of the above-mentioned vehicle luggage rack load-bearing capacity testing methods.

[0030] On the other hand, a vehicle luggage rack load-bearing capacity testing device is provided, comprising a processor and a memory for storing a computer program, wherein when the processor executes the computer program, the steps of any one of the above-described methods are implemented.

[0031] On the other hand, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by one or more processors, the steps of any of the above methods are implemented.

[0032] Compared with the prior art, the beneficial effects of the present invention are:

[0033] Through simulation analysis of 9 working conditions of the luggage rack, the structure of the luggage rack is optimized. The bench test verifies the reliability of the static load. The dynamic load test examines the deformation and bolt tightening force of the luggage rack under different environments. The three methods are used in combination to ensure that the load-bearing capacity of the luggage rack product meets the design requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a flow chart of the method of the present invention;

[0035] Figure 2 is the static load condition of the luggage rack of the present invention;

[0036] Figure 3 It is a material property table of each component of the luggage rack of the present invention;

[0037] Figure 4 is a finite element model diagram of the luggage rack of the present invention;

[0038] Figure 5 is the maximum displacement diagram of the luggage rack under various working conditions of the present invention;

[0039] Figure 6 is a displacement distribution cloud diagram of the luggage rack of the present invention;

[0040] Figure 7 is the maximum stress diagram of the luggage rack under various working conditions of the present invention;

[0041] Figure 8 It is a stress distribution cloud diagram of the luggage rack of the present invention;

[0042] Fig. 9 is the maximum stress of the luggage rack bracket under various working conditions of the present invention;

[0043] Fig.10 is a stress cloud diagram of the luggage rack support of the present invention;

[0044] Fig.11 It is a static stress analysis report diagram of the luggage rack of the present invention. DETAILED DESCRIPTION

[0045] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the application equally.

[0046] In the present invention, terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present invention, and do not specifically refer to any part or element in the present invention and should not be understood as limitations on the present invention.

[0047] Example:

[0048] like Figure 1 As shown, this embodiment provides a method for testing the bearing capacity of a vehicle luggage rack, comprising the following steps:

[0049] S1: Determine the shape of the car luggage rack and select a roof-mounted or detached luggage rack according to the shape;

[0050] S2: Set the load-bearing capacity target, define the structural form, and determine whether the luggage rack should be split or integrated;

[0051] S3: Determine the location and installation method of the luggage rack, whether to select the bolt and rivet nut form, and the number of the installation points varies according to the form of the luggage rack;

[0052] S4: Design a typical section according to the style of the luggage rack. Specifically, if the load-bearing capacity is high, the base is an aluminum alloy die-casting; if the load-bearing capacity is not high, a plastic base is used. At the same time, the wall thickness of the longitudinal beam is also a factor affecting the load-bearing capacity, which is usually designed to be 2.5mm.

[0053] S5: Formulate the luggage rack test conditions according to the usage scenarios, specifically, simulate the load-bearing capacity analysis through CAE simulation;

[0054] S6: Through static load test, the fixture on the luggage rack simulates the test conditions to determine whether it meets the design requirements;

[0055] S7: Through dynamic load test, load is added to the whole vehicle for road test, and the stress performance of the luggage rack under different working conditions is judged to determine whether it meets the design requirements.

[0056] Confirm the test conditions: In daily use, the luggage rack needs to be equipped with a crossbar in the middle, and the load object is fixed to the roof through a rope net or a metal frame. The rated load of the luggage rack in this case is designed to be 50kg. During actual driving, the luggage rack is subjected to forces from all directions. Figure 2 shown.

[0057] In step S5, the detailed method of CAE simulation analysis is as follows:

[0058] The main material of the luggage rack is aluminum alloy. The luggage rack is connected to the vehicle body through the luggage rack bracket. In the simulation analysis, the displacement of the luggage rack and the stress distribution of the luggage rack and bracket under 9 static load conditions were investigated. According to the design requirements, the maximum displacement of the luggage rack is less than 3mm. The finite element of the luggage rack is simulated by 3D units, with an average unit size of 10mm. The cross section of the luggage rack crossbar is a solid circle with a diameter of 60mm, which is connected to the luggage rack through a rigid unit. The materials of the various components of the luggage rack are as follows: Figure 3 As shown in the figure, the established finite element model of the luggage rack is as follows Figure 4 As shown;

[0059] Luggage rack displacement analysis: Through simulation analysis, the displacement of the luggage rack at each location is less than 3mm under 9 working conditions, meeting the design requirements. The displacement analysis results of the luggage rack under each working condition are as follows: Figure 5 As shown in the figure, the maximum displacement of the luggage rack under each working condition. Taking working condition 1 as an example, the simulation analysis results show that the maximum displacement is 0.4mm, and the displacement distribution cloud diagram is as follows Figure 6 As shown;

[0060] Luggage rack stress analysis: Through simulation analysis, under 9 working conditions, the maximum stress of the luggage rack is less than 120MPa, which meets the yield strength of the material. The maximum stress analysis results of the luggage rack under each working condition are as follows: Figure 7As shown, taking working condition 1 as an example, the simulation analysis results show that the maximum stress is 82MPa, and the stress distribution cloud diagram is as follows Figure 8 shown.

[0061] Through CAE analysis, under 9 working conditions, the maximum stress of the luggage rack bracket is less than 170MPa, which meets the yield strength of the material. The stress analysis results of the luggage rack under each working condition are as follows: Fig. 9 As shown, taking working condition 1 as an example, the simulation analysis structure shows that the stress of the luggage rack bracket is 14MPa, and the stress cloud diagram of the luggage rack is as follows Fig.10 shown.

[0062] The method of the static load test in step S6 is as follows: the test requires that the static load test model of the luggage rack is two luggage racks fixed on the tooling, and the relative position of the luggage rack is consistent with the actual vehicle, such as Fig.11 As shown in the figure, the distance between the two crossbars is 700mm, the size of the square weight loaded is 1000mm long and 600mm wide, and the load is firmly fixed on the luggage rack and cannot move during the test. =, the installation of the crossbeam must be considered in the test and inspection to meet the load requirements. The luggage rack carries 50KG (including the auxiliary load-bearing crossbeam). After nine different working conditions, the maximum deformation of the luggage rack is less than 3mm; in the overload tensile test, the luggage rack has no deformation and the structure has not separated. If the test results meet the above requirements, it can be determined that the static load capacity of the luggage rack assembly meets the design requirements.

[0063] The method of the dynamic load test in step S7 is: after the static load test, a dynamic load test is required during the vehicle road test stage. The dynamic load test adds load to the vehicle to directly examine the load performance and durability of the luggage rack under actual working conditions. A cross bar fixed with tooling is installed on the luggage rack, and heavy objects are installed on the cross bar for load testing.

[0064] During the test, according to the actual conditions of the OEM's test vehicles and sites, the luggage rack's road test tests include brick road load test, 7% mileage general endurance load test, S-bend load test, high-speed load test and brake load test. After the test, the luggage rack and the vehicle body showed no deformation, abnormal noise or looseness. The road test conditions of the whole vehicle are usually more stringent than normal driving conditions to ensure that the product does not fail during actual use.

[0065] This embodiment also provides a vehicle luggage rack load-bearing capacity testing system, including: a system for implementing the method steps in any of the above-mentioned vehicle luggage rack load-bearing capacity testing methods.

[0066] The contents of the above method embodiments are all applicable to the present system embodiments. The functions specifically implemented by the present system embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0067] This embodiment also provides a device, including:

[0068] at least one processor;

[0069] At least one memory for storing at least one program;

[0070] When the at least one program is executed by at least one processor, the at least one processor implements a method for testing the load-bearing capacity of a vehicle luggage rack.

[0071] This embodiment also provides a storage medium, which stores a program, and the program is executed by a processor to complete a method for testing the load-bearing capacity of a vehicle luggage rack.

[0072] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for testing the bearing capacity of a vehicle luggage rack, characterized in that: The following steps are involved: S1: Determine the shape of the car luggage rack and select a roof-mounted or detached luggage rack according to the shape; S2: Set the load-bearing capacity target, define the structural form, and determine whether the luggage rack should be split or integrated; S3: Determine the location and installation method of the luggage rack, whether to select the bolt and rivet nut form, and the number of the installation points varies according to the form of the luggage rack; S4: Design a typical section according to the style of the luggage rack, specifically: If the bearing capacity is high, the base is made of aluminum alloy die casting; If the bearing capacity is not high, use a plastic base; S5: Formulate the luggage rack test conditions according to the usage scenarios, specifically, simulate the load-bearing capacity analysis through CAE simulation; S6: Through static load test, the fixture on the luggage rack simulates the test conditions to determine whether it meets the design requirements; S7: Through dynamic load test, load is added to the whole vehicle for road test, and the stress performance of the luggage rack under different working conditions is judged to determine whether it meets the design requirements.

2. A method for testing the bearing capacity of a luggage rack of an automobile according to claim 1, characterized in that: In step S5, the CAE simulation analysis specifically includes the following steps: S51: Determine the material of the luggage rack body and the connection method between the luggage rack and the vehicle body, wherein the connection method between the luggage rack and the vehicle body is specifically: connected via a bracket; S52: Determine the luggage rack displacement, and the stress distribution of the luggage rack and the bracket under several static load conditions; S53: Establish a finite element model of the luggage rack according to steps S51-S52.

3. A method for testing the bearing capacity of a luggage rack of a vehicle according to claim 2, characterized in that: The luggage rack finite element model specifically includes luggage rack displacement analysis, luggage rack stress analysis and luggage rack bracket stress analysis.

4. A method for testing the bearing capacity of a luggage rack of an automobile according to claim 3, characterized in that: In the simulation analysis, the luggage rack displacement and the stress distribution of the luggage rack and the bracket under 9 static load conditions are analyzed. According to the design requirements, the maximum displacement of the luggage rack is less than 3mm. The finite element of the luggage rack is simulated by 3D units with an average unit size of 10mm. The cross section of the luggage rack crossbar is a solid circle with a diameter of 60mm, which is connected to the luggage rack through rigid units.

5. A method for testing the bearing capacity of a luggage rack of an automobile according to claim 3, characterized in that: The luggage rack stress analysis is specifically as follows: through simulation analysis, under 9 working conditions, the maximum stress of the luggage rack is less than 120MPa, which meets the yield strength of the material.

6. A method for testing the bearing capacity of a luggage rack of an automobile according to claim 3, characterized in that: The dynamic load test specifically includes: adding load to the whole vehicle to directly examine the load performance and durability of the luggage rack under actual working conditions; installing a cross bar fixed with tooling on the luggage rack, and adding heavy objects to the cross bar for load testing.

7. A method for testing the bearing capacity of a luggage rack of an automobile according to claim 1, characterized in that: The method of the static load test in step S6 is: The static load test model of the luggage rack is two luggage racks fixed on the tooling, and the relative position of the luggage racks is consistent with the actual vehicle; The distance between the two crossbars is 700mm, and the square weights are 1000mm long and 600mm wide, and are securely fixed on the luggage rack. The crossbeam installation meets the load-bearing requirements. The luggage rack can bear 50KG (including the auxiliary load-bearing crossbeam). After testing under nine different working conditions, the maximum deformation of the luggage rack is less than 3mm.

8. A test system based on the vehicle luggage rack load-bearing capacity test method according to claim 1, characterized in that: Used to implement the method steps in any of the above-mentioned automobile luggage rack load-bearing capacity testing methods.

9. A vehicle luggage rack load-bearing capacity testing device, characterized in that: The method comprises a processor and a memory for storing a computer program, wherein when the processor executes the computer program, the steps of any one of the above methods are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by one or more processors, the steps of any of the above methods are implemented.

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