A method for determining a quick connection structure of a reconfigurable vehicle module

Abstract

The application belongs to the field of reconfigurable vehicle module fast connection structure judgment method of reconfigurable vehicle. Bridge load calculation; Working condition calculation: working conditions include impact working condition, turning working condition, diagonal off-ground working condition (maximum torque force working condition); under impact working condition, vertical force F1 borne by one bridge and vertical force F2 borne by two bridges are calculated according to vertical load mass M3; left locking structure borne tensile force F5 and right locking structure borne tensile force F6 are calculated; tensile stress σ1 on the sub-buckling action surface of the locking structure and tensile stress σ2 on the female buckling action surface are calculated; result judgment: the reconfigurable vehicle module fast connection structure judgment method achieves the functions of simple connection structure, smooth component force transmission path, lightweight structure, convenient positioning and easy locking on the basis of realizing the free combination of the vehicle frame, the positioning and shear resistance of the connection structure are realized through the positioning pin, the structural strength and reliability are guaranteed, and the performance of the reconfigurable vehicle is improved.

Description

Technical Field

[0001] This invention belongs to the field of reconfigurable vehicle technology, and more specifically, it relates to a method for determining a quick connection structure for reconfigurable vehicle modules. Background Technology

[0002] Reconfigurable vehicle modules represent a key development direction for future combat support equipment. They can be rapidly assembled or disassembled, possessing characteristics such as reconfigurability, scalability, and high versatility, meeting the needs of multi-functional support missions. Through efficient and rapid assembly, reconfigurable vehicle modules can quickly improve their passability, power, and load-bearing capacity to meet support requirements; through efficient and rapid disassembly, they can rapidly improve their flexibility and mobility. They can be widely applied in urban warfare, off-road warfare, reconnaissance patrols, and other missions, showing very broad application prospects in the military field. In reconfigurable vehicle modules, the frames are connected by connecting structures. These connecting structures bear the bending moments and tensile forces generated under load, and are key to improving the load-bearing capacity of the frame assembly. Currently, most vehicle frame connection structures adopt mechanical structures where components bear complex combined bending and torsional loads. Therefore, to ensure the strength and reliability of the connection structure, the connection structure is heavy, occupies a large space, and is structurally complex. A small number of simple butt joint connection structures are used. Under the condition of complex combined bending and torsional loads, the stress distribution of the components is uneven, and the local stress is large, which reduces the load-bearing capacity of the frame and fails to meet the vehicle's usage requirements. Long-term use of this butt joint structure increases the risk of connection failure during frame movement.

[0003] Existing technology includes a "self-reconfigurable wheeled vehicle reconfiguration unit" (publication number CN115649288A). This technology provides a self-reconfigurable wheeled vehicle reconfiguration unit as the smallest basic unit of a self-reconfigurable wheeled vehicle. It can solve the reconfiguration problems of multiple systems such as mechanics, energy, and control in self-reconfigurable wheeled vehicles, enabling the self-reconfigurable wheeled vehicle to have a reconfigurable overall configuration while meeting the requirements of high mobility, high passability, and high driving stability. Specifically, it includes a body, battery subsystem, drive subsystem, motion subsystem, braking subsystem, steering subsystem, and reconfiguration subsystem. After two or more reconfiguration units are connected through the reconfiguration subsystem to form a self-reconfigurable wheeled vehicle, structural reconfiguration, information reconfiguration, and energy reconfiguration are completed through the connection of corresponding interfaces. Structural reconfiguration, information reconfiguration, and energy reconfiguration with the task module of the superstructure are achieved through connection. The motion subsystem is connected to the body through the motion mechanism reconfiguration subsystem for adjusting the wheel track and body height of the reconfiguration unit.

[0004] However, this technology does not address the technical issues and solutions of this application. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for determining the quick connection structure of a reconfigurable vehicle module that achieves the basic function of free combination of vehicle frame, simple connection structure, smooth force transmission path of components, lightweight structure, easy positioning and easy locking, the connection structure is positioned and resists shear force through positioning pins, and bears tensile force through locking device, and realizes the ability of different structures to withstand different types of loads, ensuring the structural strength and reliability.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] This invention relates to a method for determining a quick-connect structure for reconfigurable vehicle modules. The connection steps of this method are as follows:

[0008] S1. Axle load calculation: Calculate the load center position of the load under different working conditions and load coefficients in the front and rear directions by calculating the axle load distribution of the frame and the wheelbase. Perform stress analysis based on the load borne by the tires to determine the shear force on the locating pin bearing and the tensile force on the locking structure. Calculate the stress on the connection structure and judge the strength of the connection structure based on the allowable stress of the material.

[0009] S2. Working condition calculation: Working conditions include impact working conditions, turning working conditions, and diagonal ground clearance working conditions (maximum torque force working conditions);

[0010] Under impact conditions, force analysis along the Z direction is performed. Based on the vertical load mass M3, the vertical force F1 borne by the first bridge and the vertical force F2 borne by the second bridge are calculated. The tensile force F5 borne by the left locking structure and the tensile force F6 borne by the right locking structure are calculated. The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener of the locking structure are calculated. The shear stress τ1 on the left locating pin bearing and the shear stress τ2 on the right locating pin bearing are calculated.

[0011] Under turning conditions, the tire bears a vertical load mass M3 and a lateral load mass M4. Calculate the vertical force F1 borne by the first axle and the vertical force F2 borne by the second axle based on M3. Calculate the lateral force F3 borne by the first axle and the lateral force F4 borne by the second axle based on M4. Calculate the tensile stress σ1 on the working surface of the locking structure's male and female fasteners. Calculate the shear stress τ1 on the left locating pin bearing and the shear stress τ2 on the right locating pin bearing.

[0012] S3. Result Judgment: Calculate the allowable stress of the material and the allowable shear stress;

[0013] If the shear stress is less than the allowable shear stress, it indicates that the quick-connect structure of the reconfigurable vehicle module is qualified; otherwise, it is unqualified.

[0014] If the tensile stress is less than the allowable stress, it indicates that the quick-connect structure of the reconfigurable vehicle module is qualified; otherwise, it is unqualified.

[0015] The full load of the vehicle is M. Under static load conditions, the load of the first axle is M1, the load of the second axle is M2, the wheelbase is L, the distance of the center of gravity from the first axle is L1, and the distance of the center of gravity from the second axle is L2.

[0016] The location of the load's center of gravity is:

[0017]

[0018]

[0019] The load factors for impact, turning, and diagonal ground clearance conditions are as follows:

[0020] Impact condition: X(g): 0; Y(g): 0; Z(g): 3;

[0021] Turning condition: X(g): 0; Y(g): 0.6; Z(g): 1;

[0022] Diagonal ground clearance condition: X(g): 0; Y(g): 0; Z(g): 2.

[0023] Under impact conditions,

[0024]

[0025]

[0026] According to the principle of static equilibrium, the torque balance formula for the left locking structure is:

[0027] (F1-3*m1*g)*D1=F5*D2

[0028] The torque balance formula for the right-side locking structure is:

[0029] (F2-3*m1*g)*D1=F6*D2

[0030] The tensile force borne by the left locking structure is:

[0031]

[0032] The tensile force borne by the right-side locking structure is:

[0033]

[0034] According to the formula for calculating normal stress:

[0035]

[0036] The tensile stress σ1 on the working surface of the left locking structure's sub-lock and the tensile stress σ2 on the working surface of the female lock are respectively:

[0037]

[0038]

[0039] The tensile stress σ1 on the working surface of the right-side locking structure's sub-lock and the tensile stress σ2 on the working surface of the female lock are respectively:

[0040]

[0041]

[0042] The locating pin only bears shear stress, according to the shear stress calculation formula:

[0043]

[0044] The shear stress τ1 on the left locating pin bearing:

[0045]

[0046] The shear stress τ2 on the right-side locating pin bearing:

[0047]

[0048] Under turning conditions, the static load mass of a single frame is m1, and the static load mass of the intermediate connecting frames is m2.

[0049] Along the Z direction:

[0050] M3 = 1 * M = 1 * 10t = 10t

[0051]

[0052]

[0053] Along the Y direction:

[0054] M4 = 0.6 * M = 0.6 * 10t = 6t

[0055]

[0056]

[0057] According to the principle of static equilibrium, the torque balance of the left locking structure is as follows:

[0058] (F1-1*m1*g)*D1=F5 Z *D2

[0059] The torque balance formula for the right-side locking structure is:

[0060] (F2-1*m1*g)*D1=F6 Z *D2

[0061] The tensile force borne by the left locking structure is:

[0062]

[0063] The tensile force borne by the right-side locking structure is:

[0064]

[0065] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the left locking structure are as follows:

[0066]

[0067]

[0068] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the right-side locking structure are as follows:

[0069]

[0070]

[0071] The locating pin only bears shear stress, according to the shear stress calculation formula:

[0072]

[0073] The shear stress τ1 on the left locating pin bearing:

[0074]

[0075] The shear stress τ2 on the right-side locating pin bearing:

[0076]

[0077] Substituting the tensile force borne by the above locking structure into Hooke's Law formula.

[0078] The deformation of the left locking structure is:

[0079]

[0080] The deformation of the right-side locking structure is:

[0081]

[0082] Under lateral load, the inner locking structure loosens during turning, while the outer locking structure tightens. The inner locating pin is compressed, and the outer locating pin loosens. The distance between the center line of the load on the frame and the center of the pin is D1, and the distance between the inner locating pin and the locking structure is D3.

[0083] Under diagonal ground-lift conditions, the tires on one diagonal of the frame lift off the ground and do not bear wheel pressure loads; the tires on the other diagonal are in contact with the ground, and the tires in contact with the ground bear twice the wheel pressure load under static load conditions.

[0084] Along the Z direction:

[0085] M3 = 1 * M = 1 * 10t = 10t

[0086]

[0087]

[0088] In the diagonally off-ground condition, the positioning pins are subjected to different shear forces, and the forces on each module pin are different. Fs1, Fs2, Fs3, and Fs4 are the shear forces on each pin bearing; the distance D7 between the positioning pin and the vertical force F1, the distance D6 between the two positioning pins, and the distance D5 between the center position of a single module and the positioning pin.

[0089] According to the principle of static equilibrium,

[0090] F1=Fs1+Fs2+m1*g

[0091] F2=Fs3+Fs4+m1*g

[0092] Using the locating pin on the right as a fixed hinge support, according to the principle of torque balance:

[0093] F1*D7-Fs1*D6-m1*g*D5=0

[0094] F2*D7-Fs3*D6-m1*g*D5=0

[0095] The shear stress corresponding to each pin is:

[0096]

[0097]

[0098]

[0099]

[0100] According to the principle of action and reaction, the shear force on the intermediate module is opposite in direction to the shear force on the single module. The intermediate module is simplified as a square, and it rotates under the action of shear force.

[0101] The results were determined using the fourth strength theory to verify the material strength, with a safety factor of n.

[0102] Equivalent stress (Von Mises stress) corresponds to the fourth strength theory in mechanics of materials.

[0103]

[0104] The allowable stress of the material is calculated as follows:

[0105] [σ]=σ s / n

[0106] The allowable shear stress is calculated as follows:

[0107]

[0108] The working principle and beneficial effects of the technical solution adopted in this invention are as follows:

[0109] The method for determining the reconfigurable vehicle module quick connection structure described in this invention Attached Figure Description

[0110] The following is a brief explanation of the contents depicted in the accompanying drawings and the markings therein:

[0111] Figure 1 This is a schematic diagram of the reconfigurable vehicle module quick connection structure described in this invention;

[0112] Figure 2a This is a schematic diagram of the reconfigurable vehicle module quick connection structure described in this invention;

[0113] Figure 2b This is a schematic diagram of the reconfigurable vehicle module quick connection structure described in this invention;

[0114] Figure 3a This is a schematic diagram of the bridge load of the reconfigurable vehicle module quick connection structure described in this invention;

[0115] Figure 3b This is a schematic diagram of the frame impact load of the reconfigurable vehicle module quick-connect structure described in this invention;

[0116] Figure 4 This is a schematic diagram of the left locking structure of the quick-connect structure for the reconfigurable vehicle module described in this invention;

[0117] Figure 5a This is a schematic diagram of the components of the connection structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0118] Figure 5bThis is a schematic diagram of the components of the connection structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0119] Figure 5c This is a schematic diagram of the components of the connection structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0120] Figure 5d This is a schematic diagram of the components of the connection structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0121] Figure 6a This is a vertical force diagram illustrating the load on the chassis of the reconfigurable vehicle module quick-connect structure described in this invention under turning conditions.

[0122] Figure 6b This is a schematic diagram of the lateral force distribution on the chassis of the reconfigurable vehicle module quick-connect structure described in this invention under turning load conditions.

[0123] Figure 7 This is a schematic diagram of the deformation of the vertically stressed frame locking structure of the reconfigurable vehicle module quick-connect structure described in this invention.

[0124] Figure 8 This is a schematic diagram of the connecting clip of the quick-connect structure for reconfigurable vehicle modules described in this invention;

[0125] Figure 9 This is a schematic diagram of the force on the left locking structure of the quick-connect structure for the reconfigurable vehicle module described in this invention;

[0126] Figure 10 This is a schematic diagram of the deformation of the transversely stressed frame locking structure of the reconfigurable vehicle module quick-connect structure described in this invention.

[0127] Figure 11 This is a schematic diagram of the connecting buckle structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0128] Figure 12 This is a schematic diagram of the load on the chassis of the reconfigurable vehicle module quick-connect structure described in this invention under diagonal ground clearance conditions.

[0129] Figure 13a This is a schematic diagram showing the force on the positioning pins of each module in the reconfigurable vehicle module quick-connect structure described in this invention.

[0130] Figure 13b This is a schematic diagram showing the force on the positioning pins of each module in the reconfigurable vehicle module quick-connect structure described in this invention.

[0131] Figure 14 This is a schematic diagram of the shear force on the intermediate module of the reconfigurable vehicle module quick connection structure described in this invention.

[0132] Figure 15 This is a simplified force diagram of the intermediate module of the reconfigurable vehicle module quick-connect structure described in this invention.

[0133] Figure 16 This is a schematic diagram of the tension of the intermediate module locking structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0134] Figure 17a This is a simplified force diagram of the intermediate module of the reconfigurable vehicle module quick-connect structure described in this invention.

[0135] Figure 17b This is a simplified force diagram of the intermediate module of the reconfigurable vehicle module quick-connect structure described in this invention.

[0136] Figure 17c This is a simplified force diagram of the intermediate module of the reconfigurable vehicle module quick-connect structure described in this invention.

[0137] Figure 18 This is a schematic diagram of the tension of the intermediate module locking structure of the reconfigurable vehicle module quick connection structure described in this invention;

[0138] Figure 19 The load coefficients for the three working conditions described in this invention;

[0139] The reference numerals in the attached diagram are as follows: 1. Connecting female buckle; 2. Connecting male buckle; 3. Fixed crossbeam; 4. Positioning bushing; 5. Positioning pin; 6. Hydraulic push rod; 7. Main crossbeam; 8. Wedge block; 9. Wedge block bracket; 10. Cylinder fixing flange; 11. Hydraulic cylinder; 12. Positioning pin fixing plate. Detailed Implementation

[0140] The following description, with reference to the accompanying drawings, provides a more detailed explanation of the specific embodiments of the present invention, including the shape and structure of each component, the relative positions and connections between the parts, the functions and working principles of each part:

[0141] As attached Figure 1 - Appendix Figure 19 As shown, this invention provides a method for determining a quick-connect structure for reconfigurable vehicle modules. The connection steps of this method are as follows:

[0142] S1. Axle load calculation: Calculate the load center position of the load under different working conditions and load coefficients in the front and rear directions by calculating the axle load distribution of the frame and the wheelbase. Perform stress analysis based on the load borne by the tires to determine the shear force on the locating pin bearing and the tensile stress on the locking structure. Calculate the stress on the connection structure and judge the strength of the connection structure based on the allowable stress of the material.

[0143] S2. Working condition calculation: Working conditions include impact working conditions, turning working conditions, and diagonal ground clearance working conditions (maximum torque force working conditions);

[0144] Under impact conditions, force analysis along the Z direction is performed. Based on the vertical load mass M3, the vertical force F1 borne by the first bridge and the vertical force F2 borne by the second bridge are calculated. The tensile force F5 borne by the left locking structure and the tensile force F6 borne by the right locking structure are calculated. The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener of the locking structure are calculated. The shear stress τ1 on the left locating pin bearing and the shear stress τ2 on the right locating pin bearing are calculated.

[0145] Under turning conditions, the tire bears a vertical load mass M3 and a lateral load mass M4. Calculate the vertical force F1 borne by the first axle and the vertical force F2 borne by the second axle based on M3. Calculate the lateral force F3 borne by the first axle and the lateral force F4 borne by the second axle based on M4. Calculate the tensile stress σ1 on the working surface of the locking structure's male and female fasteners. Calculate the shear stress τ1 on the left locating pin bearing and the shear stress τ2 on the right locating pin bearing.

[0146] S3. Result Judgment: Calculate the allowable stress of the material and the allowable shear stress;

[0147] If the shear stress is less than the allowable shear stress, it indicates that the quick-connect structure of the reconfigurable vehicle module is qualified; otherwise, it is unqualified.

[0148] If the tensile stress is less than the allowable stress, it indicates that the quick-connect structure of the reconfigurable vehicle module is qualified; otherwise, it is unqualified.

[0149] The method for determining the quick connection structure of reconfigurable vehicle modules described in this invention achieves the basic function of free combination of vehicle frame, resulting in simple connection structure, smooth force transmission path of components, lightweight structure, easy positioning and easy locking. The connection structure is positioned and resists shear force through positioning pins, and bears tensile force through locking device. This enables different structures to withstand different types of loads, ensures structural strength and reliability, and improves the performance of reconfigurable vehicles.

[0150] The method for determining the reconfigurable vehicle module quick-connection structure described in this invention solves the technical problem and achieves the technical effect through the following specific solutions. These are now explained in conjunction with specific embodiments:

[0151] I. Bridge Load Calculation:

[0152] By analyzing the load distribution and wheelbase of the vehicle frame, the location of the load center of gravity can be calculated. This allows for the calculation of the load borne by each tire in the front and rear directions under different load coefficients under various working conditions. Based on the load borne by the tires, a stress analysis is performed (determining the shear force on the locating pin bearing and the tensile force on the locking structure). The stress condition of the connecting structure is then calculated, and the strength of the connecting structure is determined based on the allowable stress of the material. This also guides the structural optimization design.

[0153] The full load of the vehicle is M. Under static load conditions, the load on the first axle is M1, the load on the second axle is M2, the wheelbase is L, the distance from the center of gravity to the first axle is L1, and the distance from the center of gravity to the second axle is L2. Figure 2 is a schematic diagram of the axle load.

[0154] The location of the load's center of gravity is:

[0155]

[0156]

[0157] The vehicle's full load mass is M = 10t. Under static load conditions, the first axle load M1 = 4519kg, the second axle load M2 = 5481kg, and the wheelbase L = 3800mm. Therefore, the location of the load's center of gravity is:

[0158] L1=5481kg÷10t*3800mm=2082.78mm

[0159] L2=4519kg÷10t*3800mm=1717.22mm

[0160] This invention includes a design calculation method for the connection structure of a vehicle frame under three working conditions: impact, cornering, and diagonal ground clearance. The load factors for the three working conditions are as follows: Figure 19 As shown.

[0161] Under various operating conditions, the load borne by the tires along the coordinate system direction is the full load multiplied by the load factor. Here, it is specified that the vertical load mass borne by the tires along the Z direction is M3, and the lateral load mass borne by the tires along the Y direction is M4.

[0162] II. Operating Condition Calculation:

[0163] 1. Under impact conditions, the frame is subjected to force analysis along the Z-direction, with the tires only bearing a vertical load of mass M3. (Frame load diagram) Figure 3a As shown, F1 is the vertical force borne by the first axle, F2 is the vertical force borne by the second axle, m1 is the static load mass borne by a single frame, and m2 is the static load mass of the intermediate connecting frame. Specifically, m1 is 3820 kg and m2 is 2360 kg. Figure 3b This is a schematic diagram of the load on the vehicle frame under impact conditions.

[0164] but:

[0165] M3 = 3 * M = 3 * 10t = 30t

[0166]

[0167]

[0168] According to the stress analysis, under impact conditions, the connections between the male and female latches and wedges on the left and right sides of the upper part of the locking structure are loose and do not bear tensile force. The male and female latches and wedges on the left and right sides of the lower part of the locking structure interact with each other, locking the structure. The tensile force borne by the left locking structure is F5, and the tensile force borne by the right locking structure is F6. The contact area between the male latch and the wedge is A1, the contact area between the female latch and the wedge is A2, and the cross-sectional area at the pin connection is A3. The distance between the center line of the load on the frame and the center of the pin is D1, and the distance between the center of the wedge and the center of the positioning pin is D2. Measurements show that A1 is 1069 mm², A2 is 500 mm², A3 is 1774 mm², D1 is 949 mm, and D2 is 99 mm.

[0169] Figure 4 This is a schematic diagram of the locking structure on the left.

[0170] Figure 5a For connecting the sub-buckles, Figure 5b To connect the female buckle, Figure 5c , Figure 5d For positioning pins.

[0171] Based on the premise that the locating pin is a fixed hinge support, and according to the principle of static equilibrium, the torque balance formula for the locking structure on both sides is as follows:

[0172] (F1-3*m1*g)*D1=F5*D2

[0173] (F2-3*m1*g)*D1=F6*D2

[0174] The tensile forces borne by the locking structures on the left and right sides are as follows:

[0175]

[0176]

[0177] According to the formula for calculating normal stress:

[0178]

[0179] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the left locking structure are as follows:

[0180]

[0181]

[0182] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the right-side locking structure are as follows:

[0183]

[0184]

[0185] The locating pin only bears shear stress, according to the shear stress calculation formula:

[0186]

[0187] The shear stress τ1 on the left locating pin bearing:

[0188]

[0189] The shear stress τ2 on the right-side locating pin bearing:

[0190]

[0191] 2. Under turning conditions, force analysis along the Z-direction shows the tire bears a vertical load of mass M3, and force analysis along the Y-direction shows the tire bears a lateral load of mass M4. (See chassis load diagram.) Figure 4 As shown, F1 is the vertical force borne by the first axle, F2 is the vertical force borne by the second axle, F3 is the lateral force borne by the first axle, F4 is the vertical and lateral force borne by the second axle, m1 is the static load mass borne by a single frame, and m2 is the static load mass of the intermediate connecting frame.

[0192] Figure 6a , Figure 6b This is a schematic diagram of the load on the chassis during cornering, where 6a represents the vertical force. Figure 6b It is subjected to lateral force;

[0193] Then along the Z direction:

[0194] M3 = 1 * M = 1 * 10t = 10t

[0195]

[0196]

[0197] Along the Y direction:

[0198] M4 = 0.6 * M = 0.6 * 10t = 6t

[0199]

[0200]

[0201] The locking structure is subjected to both vertical (Z-direction) and lateral (Y-direction) loads. The superposition method is used to determine the connection state of the structure and calculate the stress state of the structure.

[0202] The stress state of the vertically loaded locking structure is the same as that of the connection state under the aforementioned impact condition. Using the locating pin as a fixed hinge support, according to the principle of static equilibrium, the torque balance formulas for the locking structures on both sides are:

[0203] (F1-1*m1*g)*D1=F5 Z *D2

[0204] (F2-1*m1*g)*D1=F6 Z *D2

[0205] The tensile forces borne by the locking structures on the left and right sides are respectively:

[0206]

[0207]

[0208] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the left locking structure are as follows:

[0209]

[0210]

[0211] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the right-side locking structure are as follows:

[0212]

[0213]

[0214] The locating pin only bears shear stress, according to the shear stress calculation formula:

[0215]

[0216] The shear stress τ1 on the left locating pin bearing:

[0217]

[0218] The shear stress τ2 on the right-side locating pin bearing:

[0219]

[0220] As shown in Figure 6(a), the frame rotates around the center of the locating pin at an angle of θ. The rotation angle is small and its influence on the locating pin can be ignored. The upper part of the locking structure is loose, while the lower part is tightened, with a deformation of ΔX1. The distance from the center of the connecting buckle to the working surface is X, which is 165 mm. A4 is the equivalent cross-sectional area of ​​the connecting buckle, which is 1069 mm².

[0221] Figure 7 This is a schematic diagram of the deformation of the locking structure of the vertically stressed vehicle frame.

[0222] Figure 8 Schematic diagram of the connecting buckle structure.

[0223] According to the formula for Hooke's Law, we know that:

[0224]

[0225] E—Modulus of elasticity; the modulus of elasticity of steel is 210 GPa.

[0226] X — Original length of the structural component.

[0227] Substituting the tensile force borne by the above locking structure into Hooke's law formula, the deformation of the locking structures on the left and right sides is:

[0228]

[0229]

[0230] That is: the upper left locking structure of the frame moves 0.025mm in the loosening direction, and the lower left locking structure deforms 0.025mm in the tensioning direction; the upper left locking structure of the frame moves 0.059mm in the loosening direction, and the lower left locking structure deforms 0.059mm in the tensioning direction.

[0231] Under lateral load, the inner locking structure loosens during turning, while the outer locking structure tightens. The inner locating pin is compressed, and the outer locating pin loosens. The distance between the load centerline of the frame and the center of the pin is D1, and the distance between the inner locating pin and the locking structure is D3. Measurements show that D1 is 949mm and D3 is 893mm.

[0232] Figure 9 Schematic diagram of the force distribution on the left locking structure.

[0233] Using the inner locating pin as a fixed hinge support, a force analysis is performed. Based on the principle of static equilibrium, the torque balance formulas for the locking structures on both sides are as follows:

[0234] F3*D1=F5 Y *D3

[0235] F4*D1=F6 Y *D3

[0236] The tensile forces borne by the locking structures on the left and right sides are respectively:

[0237]

[0238]

[0239] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the left locking structure are as follows:

[0240]

[0241]

[0242] The tensile stress σ1 on the working surface of the male fastener and the tensile stress σ2 on the working surface of the female fastener in the right-side locking structure are as follows:

[0243]

[0244]

[0245] The locating pin only bears shear stress, according to the shear stress calculation formula:

[0246]

[0247] The shear stress τ1 on the left locating pin bearing:

[0248]

[0249] The shear stress τ2 on the right-side locating pin bearing:

[0250]

[0251] Schematic diagram of deformation of the lateral load-bearing frame locking structure Figure 8 It can be seen that the outer locating pin of the frame is loose, while the inner locating pin is tightened. Taking the center of the inner locating pin as the rotation center point, the rotation angle is θ, which is very small. The outer locking structure is tightened, with a deformation of ΔX2. The inner locking structure of the frame is loose, with a displacement of ΔX3. Measurements show that D4 is 105mm.

[0252] Figure 10 This is a schematic diagram of the deformation of the locking structure of the frame under lateral stress.

[0253] Figure 11 This is a schematic diagram of the connecting buckle structure.

[0254] Substituting the tensile force borne by the above locking structure into Hooke's Law, the deformation of the locking structures on both sides is:

[0255]

[0256]

[0257] in addition:

[0258]

[0259]

[0260]

[0261] In summary, due to ΔX1 左 >ΔX2 左 ΔX1 右 >ΔX2 右 The upper locking structure on the outer side of the turn is in a loose state; ΔX1 left > ΔX3 left, ΔX1 right > ΔX3 right, and the lower locking structure on the inner side of the turn is in a tightened state. That is, in the entire locking structure, the upper locking structure is in a loose state, and the lower locking structure is in a tightened and stressed state.

[0262] Then, the tensile stress σ1 on the inner and outer working surfaces of the left locking structure, the tensile stress σ2 on the working surface of the female buckle, and the shear stress τ1 on the locating pin bearing are respectively:

[0263] σ1 左内 =σ1 Z左 =31MPa

[0264] σ2 左内 =σ2 Z左 =67MPa

[0265] σ1 左外 =σ1 Z左 +σ1 Y左 31MPa + 13MPa = 44MPa

[0266] σ2 左外 =σ2 Z左 +σ2 Y左 =67MPa + 29MPa = 96MPa

[0267]

[0268] τ1 左外 =τ1 Z左 =1.97MPa

[0269] Then, the tensile stress σ1 on the inner and outer working surfaces of the right-side locking structure, the tensile stress σ2 on the working surface of the female buckle, and the shear stress τ2 on the locating pin bearing are respectively:

[0270] σ1 右内 =σ1 Z右 =74MPa

[0271] σ2 右内 =σ2 Z右 =159MPa

[0272] σ1 右外 =σ1 Z右 +σ1 Y右 =74MPa + 16MPa = 90MPa

[0273] σ2 右外 =σ2 Z右 +σ2 Y右 =159MPa + 35MPa = 194MPa

[0274]

[0275] τ1 右外 =τ1 Z右 =4.7MPa

[0276] 3. In diagonal ground clearance conditions, one diagonal tire lifts off the ground and does not bear wheel load; the other diagonal tire touches the ground, and the tire in contact with the ground bears twice the wheel load under static load. (Chassis load diagram) Figure 4 As shown, F1 is the vertical force borne by the first axle tire, F2 is the vertical force borne by the second axle tire, m1 is the static load mass borne by a single frame, and m2 is the static load mass of the intermediate connecting frame.

[0277] According to the force analysis, under the diagonal ground lifting condition, the side of the tire that touches the ground bears a vertical force F. Under the action of the vertical force F, it rotates around the positioning pin. During the rotation, the locking structure that is close to the grounded tire on the same side is in a state of tension at the top and looseness at the bottom, while the locking structure that is far away on the same side is in a state of looseness at the top and tension at the bottom.

[0278] Figure 12 This is a schematic diagram of the load on the vehicle frame under diagonal ground-lift conditions.

[0279] Then along the Z direction:

[0280] M3 = 1 * M = 1 * 10t = 10t

[0281]

[0282]

[0283] The force diagram of the single-module pin shaft of the reconfigurable frame under diagonal ground clearance is shown in the figure. The positioning pin shafts bear different shear forces under diagonal ground clearance, and the forces on each module pin shaft are different. Fs1, Fs2, Fs3, and Fs4 represent the shear forces on each pin shaft. Specifically, the distance D7 between the positioning pin shaft and the vertical force F1 is 1457 mm, the distance D6 between two positioning pin shafts is 788 mm, and the distance D5 from the center of the single module to the positioning pin shaft is 394 mm.

[0284] Figure 13a , Figure 13b A schematic diagram showing the force distribution on the positioning pins of each module.

[0285] According to the principle of static equilibrium,

[0286] F1=Fs1+Fs2+m1*g

[0287] F2=Fs3+Fs4+m1*g

[0288] Using the locating pin on the right as a fixed hinge support, according to the principle of torque balance:

[0289] F1*D7-Fs1*D6-m1*g*D5=0

[0290] F2*D7-Fs3*D6-m1*g*D5=0

[0291] By solving the simultaneous equations, we can obtain the following:

[0292] Fs1 = 67155.6 N

[0293] Fs2 = -54765.6 N (upward direction)

[0294] Fs3 = 84942.8N

[0295] Fs4 = -62932.8 N (upward direction)

[0296] The shear stress corresponding to each pin is:

[0297]

[0298]

[0299]

[0300]

[0301] Taking the intermediate module as the research object, the shear force diagram of the intermediate module is as follows: Figure 14As shown. According to the principle of action and reaction, the shear force on the intermediate module is opposite in direction to the shear force on the single module. The intermediate module is simplified as a rectangle, and it rotates under the action of the shear force. A simplified schematic diagram of the intermediate module is shown below. Figure 15 As shown in the diagram. Under the action of torque, the tensile force diagram of the intermediate module locking structure is as follows. Figure 16 As shown.

[0302] The intermediate module is a simple force-bearing structure Figure 15 For reference, a partial stress analysis is performed, with points A and C as fixed ends. Based on the stress analysis, point D will not experience lateral displacement under the locking structure, but will only experience vertical displacement under shear force. The vertical displacement of point D is V mm. A simplified diagram of the partial stress on the intermediate module is shown below. Figure 17a As shown; for Figure 17a By decomposition, we can see that the two schematic diagrams are as follows: Figure 17b As shown, the displacement of point D is Vmm. The force at point D in segment AD is f1, and the force at point D in segment CD is f2. The sum of f1 and f2 is Fs4. Under shear force, the bending moment of the locking structure is as follows: Figure 17c As shown in the diagram. The bending moment causes the locking structure to tighten, and the tensile force on the locking structure is illustrated in the diagram below. Figure 18 As shown.

[0303] According to the relevant calculation formulas of the displacement method in structural mechanics:

[0304]

[0305]

[0306] According to measurements, the moment of inertia I1 of section AD is 1.138*108mm4, and the moment of inertia I2 of section CD is 6.96*107mm4. The entire frame module is made of steel, and the modulus E of steel is 2.1*1011 Pa. Measurements show that the lateral distance D8 of the locking structure is 998mm, the frame length D9 is 1917mm, and the vertical distance D10 of the locking structure is 199mm.

[0307]

[0308]

[0309] Fs4=f1+f2

[0310] By combining the above equations, the displacement of point D is:

[0311] V = 0.29 mm

[0312] but:

[0313]

[0314] According to the torque balance formula, we know that:

[0315]

[0316] Then the tensile stress σ1D on the working surface of the connecting female buckle at point D and the tensile stress σ2D on the working surface of the connecting female buckle are respectively:

[0317]

[0318]

[0319] Similarly, F5, F7, and F8 of the locking structures at different positions can be obtained as follows:

[0320] F5 = 121270.56 N

[0321] F7 = 98896.51N

[0322] F8 = 1153390.94 N

[0323] Then the tensile stress σ1A on the working surface of the connecting female buckle at point A and the tensile stress σ2A on the working surface of the connecting female buckle are respectively:

[0324]

[0325]

[0326] Then the tensile stress σ1B on the working surface of the connecting female buckle at point B and the tensile stress σ2B on the working surface of the connecting female buckle are respectively:

[0327]

[0328]

[0329] Then the tensile stress σ1C on the working surface of the connecting female buckle at point C and the tensile stress σ2C on the working surface of the connecting female buckle are respectively:

[0330]

[0331]

[0332] III. Result Interpretation:

[0333] The results were determined using the fourth strength theory to verify the material strength, with a safety factor of n.

[0334] Equivalent stress (Von Mises stress) corresponds to the fourth strength theory in mechanics of materials:

[0335]

[0336] Material allowable stress calculation:

[0337] [σ]=σ s / n

[0338] Allowable shear stress calculation:

[0339]

[0340] When judging the results:

[0341] If the shear stress is less than the allowable shear stress, the reconfigurable vehicle module quick-connect structure is qualified; otherwise, it is unqualified. If the tensile stress is less than the allowable stress, the reconfigurable vehicle module quick-connect structure is qualified; otherwise, it is unqualified.

[0342] The method for determining the quick connection structure of reconfigurable vehicle modules described in this invention achieves the basic function of free combination of vehicle frame, resulting in simple connection structure, smooth force transmission path of components, lightweight structure, easy positioning and easy locking. The connection structure is positioned and resists shear force through positioning pins, and bears tensile force through locking device. This enables different structures to withstand different types of loads, ensures structural strength and reliability, and improves the performance of reconfigurable vehicles.

[0343] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A method for determining a quick-connect structure for a reconfigurable vehicle module, wherein the connection structure is positioned and resists shear force through a locating pin, and withstands tensile force through a locking structure; Its features are: The steps of the method for determining the quick connection structure of the reconfigurable vehicle module are as follows: S1. Axle load calculation: Calculate the load center position of the load under different working conditions and load coefficients in the front and rear directions by calculating the axle load distribution of the frame and the wheelbase. Perform stress analysis based on the load borne by the tires to determine the shear force on the locating pin bearing and the tensile force on the locking structure. Calculate the stress on the connection structure and judge the strength of the connection structure based on the allowable stress of the material. S2. Working condition calculation: Working conditions include impact working conditions, turning working conditions, and diagonal ground clearance working conditions; Under impact conditions, the connection between the male and female fasteners and wedges on the left and right sides of the upper part of the locking structure becomes loose and does not bear tensile force. The male and female fasteners and wedges on the left and right sides of the lower part of the locking structure interact with each other, and the locking structure is locked. Force analysis along the Z direction: Calculate the vertical force F1 borne by bridge 1 and the vertical force F2 borne by bridge 2 based on the vertical load mass M3. Calculate the tensile force F5 borne by the left locking structure and the tensile force F6 borne by the right locking structure; calculate the tensile stress on the action surface of the locking structure's sub-buckle.

1. Tensile stress on the working surface of the female buckle 2; Calculate the shear stress on the left locating pin bearing.

1. Shear stress on the right locating pin bearing 2; Under turning conditions, the inner locking structure loosens under lateral load, while the outer locking structure tightens. The inner locating pin is compressed, and the outer locating pin loosens. The tire bears a vertical load of mass M3 and a lateral load of mass M4. Calculate the vertical force F1 borne by the first axle and the vertical force F2 borne by the second axle based on M3. Calculate the lateral force F3 borne by the first axle and the lateral-lateral force F4 borne by the second axle based on M4. Calculate the tensile stress on the locking structure's latch surface.

1. Tensile stress on the working surface of the female buckle 2; Calculate the shear stress on the left locating pin bearing.

1. Shear stress on the right locating pin bearing 2; S3. Result Judgment: Calculate the allowable stress of the material and the allowable shear stress; If the shear stress is less than the allowable shear stress, it indicates that the quick-connect structure of the reconfigurable vehicle module is qualified; otherwise, it is unqualified. If the tensile stress is less than the allowable stress, it indicates that the quick-connect structure of the reconfigurable vehicle module is qualified; otherwise, it is unqualified.

2. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 1, characterized in that: The full load of the vehicle is M. Under static load conditions, the load of the first axle is M1, the load of the second axle is M2, the wheelbase is L, the distance of the center of gravity from the first axle is L1, and the distance of the center of gravity from the second axle is L2. The location of the load's center of gravity is: ； ； The load factors for impact, turning, and diagonal ground clearance conditions are as follows: Impact condition: X(g): 0; Y(g): 0; Z(g): 3; Turning condition: X(g): 0; Y(g): 0.6; Z(g): 1; Diagonal ground clearance condition: X(g): 0; Y(g): 0; Z(g):

2.

3. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 2, characterized in that: Under impact conditions, ； ； According to the principle of static equilibrium, the torque balance formula for the left locking structure is: ； The torque balance formula for the right-side locking structure is: ； The tensile force borne by the left locking structure is: ； The tensile force borne by the right-side locking structure is: ； F1 is the vertical force borne by the first axle, F2 is the vertical force borne by the second axle, m1 is the static load mass borne by a single frame, the distance between the center line of the load on the frame and the center of the pin is D1, and the distance between the center of the wedge block and the center of the positioning pin is D2.

4. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 3, characterized in that: According to the formula for calculating normal stress: ； Tensile stress on the working surface of the left locking structure sub-clamp 1. Tensile stress on the working surface of the female fastener 2 are respectively: ； ； Tensile stress on the working surface of the right-side locking structure 1. Tensile stress on the working surface of the female fastener 2 are respectively: ； ； The locating pin only bears shear stress, according to the shear stress calculation formula: ； Shear stress on the left locating pin bearing 1: ； Shear stress on the right locating pin bearing 2: ； The contact area between the male buckle and the wedge is A1, the contact area between the female buckle and the wedge is A2, and the cross-sectional area of ​​the pin connection is A3.

5. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 4, characterized in that: Under turning conditions, the static load mass of a single frame is m1, and the static load mass of the intermediate connecting frames is m2. Along the Z direction: ； ； ； Along the Y direction: ； ； ； According to the principle of static equilibrium, the torque balance of the left locking structure is as follows: ； The torque balance formula for the right-side locking structure is: ； The tensile force borne by the left locking structure is: ； The tensile force borne by the right-side locking structure is: ； Tensile stress on the working surface of the left locking structure and the sub-locking mechanism.

1. Tensile stress on the working surface of the female fastener 2 are respectively: ； ； Tensile stress on the working surface of the right-side locking structure and the sub-locking mechanism.

1. Tensile stress on the working surface of the female fastener 2 are respectively: ； 。 6. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 5, characterized in that: The locating pin only bears shear stress, according to the shear stress calculation formula: ； Shear stress on the left locating pin bearing 1: ； Shear stress on the right locating pin bearing 2: 。 7. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 5, characterized in that: Substituting the tensile force borne by the above locking structure into Hooke's Law formula. The deformation of the left locking structure is: ； The deformation of the right-side locking structure is: ； The distance from the center of the connector buckle to the working surface is X, the elastic modulus is E, and the equivalent cross-sectional area of ​​the connector buckle is A4.

8. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 1, characterized in that: Under diagonal ground-lift conditions, the tires on one diagonal of the frame lift off the ground and do not bear wheel pressure loads; the tires on the other diagonal are in contact with the ground, and the tires in contact with the ground bear twice the wheel pressure load under static load conditions. Along the Z direction: ； ； ； In the diagonally off-ground condition, the positioning pins are subjected to different shear forces, and the forces on each module pin are different. Fs1, Fs2, Fs3, and Fs4 are the shear forces on each pin bearing.

9. The method for determining the quick connection structure of reconfigurable vehicle modules according to claim 8, characterized in that: According to the principle of static equilibrium, ； ； Using the locating pin on the right as a fixed hinge support, according to the principle of torque balance: ； ； The distance D7 between the locating pin and the vertical force F1, the distance D6 between the two locating pins, and the distance D5 between the center position of the single module and the locating pin; The shear stress corresponding to each pin is: ； ； ； 。 10. The method for determining the quick connection structure of the reconfigurable vehicle module according to claim 7, characterized in that: The results were determined using the fourth strength theory to verify the material strength, with a safety factor of n. Equivalent stress corresponds to the fourth strength theory in mechanics of materials. ； The allowable stress of the material is calculated as follows: ； The allowable shear stress is calculated as follows: 。

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