Simulation Method and System for Testing the Opening Time of a Vehicle Storage Box

Abstract

The present invention discloses a simulation method for testing the opening time of a vehicle storage box, wherein the storage box includes a support frame, a storage hopper capable of opening relative to the support frame, and a damping module; the simulation method includes the steps of: 100: Based on the CAD data of the storage box and the material density of the storage hopper, extracting the three-dimensional position coordinates of selected feature points, the mass of the storage hopper, and the moment of inertia of the storage hopper; 200: Based on the three-dimensional position coordinates of the selected feature points, the mass of the storage hopper, and the moment of inertia of the storage hopper, respectively building a kinematic model of the storage hopper and a dynamic model of the storage box; 300: According to the obtained kinematic model and dynamic model, integrating to obtain a second-order differential simulation model of the complete storage box; 400: Performing simulation based on the simulation model. Correspondingly, the present invention also discloses a simulation system for testing the opening time of a vehicle storage box.

Description

Technical Field

[0001] The present invention relates to a computer-aided design technology for vehicle design, and particularly to a simulation method and system for vehicle testing. Background Art

[0002] When a user selects to purchase a vehicle, the cockpit function configuration of the vehicle is an important indicator. As part of the vehicle's comfort and practical functional configuration, the application of a storage box in the cockpit will be indispensable, which can meet and improve the intelligent travel and convenient storage needs of users during the use of the vehicle. To achieve the simplicity of the cockpit environment and the purpose of hidden storage, the storage box will perform opening and closing operations through a motion mechanism. During the opening process of the storage box, if the opening speed is too fast, it is easy to produce a cheap feeling of the vehicle and the risk of hurting the user's legs. If the opening speed is too slow, it will also cause the user to feel bored. Therefore, the development test of the opening time of the vehicle storage box is very important.

[0003] At present, in order to achieve cost control, most automobile manufacturers have cancelled the small-batch mold trial production of vehicle storage boxes in the traditional prototype vehicle trial production stage. Therefore, in the early development stage, there are no samples for testing the opening time of vehicle storage boxes to guide the optimization of mass-produced parts, resulting in pain points such as the storage box often opening too fast or too slow during mass production in the later stage. When optimizing it, other potential problems often occur.

[0004] Based on this, it is expected to provide a virtual simulation method for vehicle storage boxes to verify the opening time effect of the part, thereby saving a large amount of mold costs and labor costs. Summary of the Invention

[0005] One of the purposes of the present invention is to provide a simulation method for testing the opening time of a vehicle storage box. This method can be compatible with the co-pilot side storage box parts of all vehicle models on the current market, and is object-oriented designed, making it simple and fast for users to operate. By inputting the three-dimensional coordinate data, part mass, moment of inertia, and other information of the selected feature points of the vehicle storage box in the simulation system, the simulation time calculation during the opening process of the storage box, the opening angle, angular velocity, angular acceleration, the real-time characteristic relationship with the opening time, the gravity moment, damping moment, force arm, and the characteristic relationship with the opening angle / time can be realized, thus solving the virtual simulation requirements for testing the opening time of existing vehicle storage boxes. At the same time, for the storage box, it also promotes its efficient and low-cost effective development, and further promotes the wide application of cockpit digital simulation.

[0006] To achieve the above object, the present invention proposes a simulation method for testing the opening time of a vehicle storage box, wherein the storage box includes a support frame, a storage bucket that can be opened relative to the support frame, and a damping module; the simulation method includes the steps:

[0007] 100: Based on the CAD data of the storage box and the material density of the storage hopper, extract the three-dimensional position coordinates of the selected feature points, the mass of the storage hopper, and the moment of inertia of the storage hopper;

[0008] 200: Based on the three-dimensional position coordinates of the selected feature points, the mass of the storage hopper, and the moment of inertia of the storage hopper, respectively build the kinematic model of the storage hopper and the dynamic model of the storage box;

[0009] 300: According to the obtained kinematic model and dynamic model, integrate to obtain a complete second-order differential simulation model of the storage box;

[0010] 400: Perform simulation based on the simulation model.

[0011] Preferably, in order to facilitate the iterative solution of the simulation solver, in step 300, the second-order differential simulation model can be transformed into two first-order differential simulation models based on modern control theory.

[0012] Further, step 400 of the simulation method described in the present invention includes: when performing simulation, set and update the simulation time according to whether the simulation result of the iterative solution converges, and the simulation ends until a convergent test result is obtained.

[0013] Further, in the simulation method described in the present invention, the selected feature points include: two side suspension points P1 and P2 where the storage hopper is installed on the support frame, the centroid point P of the storage hopper, the rotation point P3 of the limiting mechanism of the storage hopper, the fixed points P4, P5, and P6 of the limiting mechanism of the support frame, and two side suspension points P7 and P8 for fixing the damping module, where P7 can represent the fixed end of the damping module, and P8 can represent the movable end of the damping module. G point, the rotation point P3 of the limiting mechanism of the storage hopper, the fixed points P4, P5, and P6 of the limiting mechanism of the support frame, and two side suspension points P7 and P8 for fixing the damping module, where P7 can represent the fixed end of the damping module, and P8 can represent the movable end of the damping module.

[0014] Further, in step 200 of the simulation method described in the present invention, building the kinematic model of the storage hopper includes: defining the coordinate system and building the opening angle model of the storage hopper.

[0015] In some embodiments, defining the coordinate system includes: defining the global geodetic coordinate system and / or the local coordinate system of the storage hopper, and defining the origin position and the positive direction of the coordinate system.

[0016] In some specific embodiments, the global geodetic coordinate system can adopt the vehicle coordinate system X in Catia / UG E -Y E -Z E .

[0017] In some specific embodiments, the +y of the local coordinate system of the storage hopper LThe axial direction can be determined by the position of the rotation axis of the storage hopper (the two suspension points on both sides where the storage hopper is installed on the support frame), pointing from the driver's side of the vehicle to the passenger's side, +z L The axial direction can be determined by the centroid point P of the storage hopper G and the perpendicular intersection point P of the centroid point to the +y L axis O The positive direction is determined by the intersection point P O pointing to P G , +x L The positive direction of the +x axis is orthogonal to the +y L axis and the +z L axis, where the origin position is defined at the perpendicular intersection point P O .

[0018] Furthermore, in some embodiments, when building the opening angle model of the storage hopper (or the maximum opening angle model of the storage hopper), the selected feature points may include: the rotation point P of the limiting mechanism of the storage hopper, the fixed points P, P, P of the limiting mechanism of the support frame, where the fixed points P, P, P form a limiting module plane. When the initial P point on the storage hopper rotates into the plane formed by the P, P, P points, the rotation angle at this time is the maximum angle θ that the storage hopper can open max , and its intersection point in the limiting plane is P′; then, by using the vectors formed by the P A point (the perpendicular positive intersection point from the initial P point to the rotation axis of the storage hopper) with the P point and the P′ point respectively, the included angle θ max between the vectors can be solved, and the smaller value among them is taken as θ max .

[0019] Further, in step 200 of the simulation method described in the present invention, building the dynamic model of the storage box includes: building the gravity moment model of the storage hopper and building the damping moment model of the damping module

[0020] In some embodiments, building the damping moment model of the damping module includes real-time calculation of the damping force and real-time calculation of the lever arm size of the damping module on the storage hopper

[0021] Considering the influence of the dead travel size Δ damper of the damping module in the production and manufacturing process, according to the size of Δ damper the rotation angle size θ damper of the storage hopper corresponding to the dead travel can be calculated, and at the same time, the relationship characteristics between the damping force F damper obtained by calibrating the damping module and the damping moving speed V damper are determined

[0022] In addition, the damping velocity V can be obtained from the suspension points P7 and P8, and the perpendicular orthocenter of point P8 to the rotation axis of the storage hopper respectively. damper And the relationship with the rotation angle θ of the storage hopper i As well as the force arm L of the damping module relative to the storage hopper dampr And the relationship with the rotation angle θ of the storage hopper i When the rotation angle of the storage hopper is θ i ≥θ damper At this time, the damping moment M damper The magnitude is 0, otherwise the damping moment is M damper = F damper ·L damper .

[0023] In some embodiments, building the gravity moment model of the storage hopper includes determining the mass m L Magnitude and the centroid P G Position determination, and calculating the real-time force arm magnitude of the gravity of the storage hopper.

[0024] Among them, the mass m L Magnitude and the centroid P G Position coordinates can be input into the CAD data of the storage box according to the density of each loose part material of the storage hopper, and obtained in 3D software, such as Catia / UG.

[0025] The force arm L of the gravity moment G And the relationship with the rotation angle θ of the storage hopper i Can be expressed as: L G = ‖P G _P O ‖·sin(θ G_initial +θ i ), where θ G_initial Represents the angle between the local coordinate system z L Axis (the line connecting the centroid P G Of the storage hopper and P O ) and the earth coordinate system z E . Then when the rotation angle of the storage hopper is The gravity moment M G The magnitude is M G = m L g·L G , otherwise the damping moment is

[0026] In this technical solution, during the opening process of the storage hopper, the positions of its centroid P G And the position of the moving suspension point P8 of the damping module are both changing dynamically. If it is assumed that their positions are at the opening angle θ of the storage hopper iThe position vector coordinates at that time are P Gi (x Gi , y Gi , z Gi ) and P 8i (x 8i , y 8i , z 8i ), then P Gi can be expressed as:

[0027]

[0028] where is the coordinate system transformation matrix, P G_initial is the P of the centroid point of the storage hopper G initial position coordinate, (x0, y0, z0) represents the position coordinate of point P O .

[0029] For P 8i , if θ i ≤θ 8_initial ,

[0030]

[0031] Conversely, if θ i >θ 8_initial ,

[0032]

[0033] where, P 8_initial is the initial position coordinate of the moving suspension point P8 of the damping module, θ 8_initial is the angle between the initial position of P 8_initial and the z L axis, P B (x B , y B , z B ) is the position coordinate of the vertical positive intersection point from the initial P 8_initial point to the rotation axis of the storage hopper.

[0034] Furthermore, in the simulation method described in the present invention, the second-order differential simulation model is constructed as:

[0035]

[0036] where I y represents the moment of inertia of the storage hopper about the rotation axis, which is a value obtained in the storage box CAD, represents the angular acceleration of the storage hopper, g represents the acceleration due to gravity, m L represents the mass of the storage hopper, L G represents the lever arm of the gravity moment, Fdamper denotes the damping force obtained by the damping module, L dampr denotes the lever arm of the damping module relative to the storage hopper.

[0037] Furthermore, step 300 of the simulation method according to the present invention further includes: converting the second-order differential simulation model into two first-order differential simulation models; where let u1 = θ i , Then the two first-order differential simulation models are: where denotes the angular velocity of the storage hopper, θ i denotes the rotation angle of the storage hopper.

[0038] Furthermore, in step 400 of the simulation method according to the present invention, based on the simulation, at least one of the following is obtained: the opening time of the storage box, the opening angle, the opening angular velocity, the opening angular acceleration, the real-time relationship between at least one of the opening angle, the opening angular velocity, and the opening angular acceleration and the opening time, the relationship between at least one of the gravitational moment, the damping moment, and the lever arm of the storage box and the opening angle, and the relationship between at least one of the gravitational moment, the damping moment, and the lever arm of the storage box and the opening time.

[0039] Another object of the present invention is to provide a simulation system for testing the opening time of a vehicle storage box. By inputting information such as the three-dimensional coordinate data of the selected characteristic points of the vehicle storage box, the part mass, and the moment of inertia in this simulation system, the simulation time calculation during the opening process of the storage box, the real-time characteristic relationships between the opening angle, angular velocity, angular acceleration, and opening time, and the characteristic relationships between the gravitational moment, damping moment, lever arm and opening angle / time can be realized, thus solving the virtual simulation requirements for testing the opening time of existing vehicle storage boxes. At the same time, for the storage box, it also promotes efficient and low-cost effective development, and further promotes the wide application of cockpit digital simulation.

[0040] Based on the above object, the present invention provides a simulation system for testing the opening time of a vehicle storage box, which executes the above simulation method.

[0041] The simulation method and system for testing the opening time of a vehicle storage box according to the present invention can effectively solve the virtual simulation requirements for testing the opening time of existing vehicle storage boxes. At the same time, for the storage box, it also promotes efficient and low-cost effective development, and further promotes the wide application of cockpit digital simulation. Description of the Drawings

[0042] Figure 1 Schematically shows the state of the vehicle storage box when it is fully closed.

[0043] Figure 2Schematically shows the state of the vehicle storage box when it is fully opened.

[0044] Figure 3 Shows the limiting module in the vehicle storage box.

[0045] Figure 4 Shows the flowchart of the steps of the simulation method for testing the opening time of the vehicle storage box according to the present invention in one embodiment.

[0046] Figure 5 Schematically shows the selection of the characteristic points of the rotation axis of the storage hopper in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0047] Figure 6 Schematically shows the selection of the characteristic points of the opening angle of the storage hopper in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0048] Figure 7 Schematically shows the selection of the characteristic points of the fixed damping module in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0049] Figure 8 Schematically shows the central position point of the storage hopper on the rotation axis in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0050] Figure 9 Schematic diagram of the calculation method of the dynamic position vector of the centroid of the storage hopper in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0051] Figure 10 Schematic diagram of the calculation method of the dynamic position vector of the suspension point of the damping module in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0052] Figure 11 Schematic diagram of the calculation method of the maximum opening angle of the storage hopper in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0053] Figure 12 For the damping moment M of the damping module in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention damper Calculation method schematic diagram.

[0054] Figure 13 Shows the algorithm flow of the damping moment of the damping module in one embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0055] Figure 14 The gravitational torque M of the storage bin in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention G Schematic diagram of the calculation method.

[0056] Figure 15 Shows the algorithm flow of the gravitational torque of the storage bin in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0057] Figure 16 Schematic diagram of the calculation method of the storage box assembly model in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0058] Figure 17 Comparison diagram of the simulation results and test results based on the opening angle of the storage bin in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0059] Figure 18 Comparison diagram of the simulation results and test results based on the opening angular acceleration of the storage bin in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention. Specific embodiments

[0060] The following will further explain and illustrate the simulation method and system for testing the opening time of the vehicle storage box according to the present invention in conjunction with the accompanying drawings of the specification and specific embodiments. However, such explanations and illustrations shall not unduly limit the technical solution of the present invention.

[0061] Figure 1 Schematically shows the state of the vehicle storage box when it is fully closed.

[0062] Figure 2 Schematically shows the state of the vehicle storage box when it is fully opened.

[0063] Figure 3 Shows the limiting module in the vehicle storage box.

[0064] In this embodiment, the simulation method according to the present invention is used to perform a simulation test on the vehicle storage box as shown in Figure 1 , Figure 2 and Figure 3 to test its opening time.

[0065] Such as Figure 1 , Figure 2 and Figure 3As shown, the storage box or storage box assembly includes a support frame 2, a storage hopper 1 that can be opened relative to the support frame, a damping module 3, and a limiting block 5 for limiting the storage hopper when it is opened to the maximum angle, where a handle 4 is provided on the storage hopper 1.

[0066] Figure 4 It shows the step flowchart of the simulation method for testing the opening time of the vehicle storage box according to the present invention in an embodiment.

[0067] In this embodiment, the simulation method for testing the opening time of the vehicle storage box includes the steps:

[0068] 100: Based on the CAD data of the storage box and the material density of each component of the storage hopper, extract the three-dimensional position coordinates of the selected feature points, the mass of the storage hopper, and the moment of inertia of the storage hopper;

[0069] 200: Based on the three-dimensional position coordinates of the selected feature points, the mass of the storage hopper, and the moment of inertia of the storage hopper, respectively build the kinematic model of the storage hopper and the dynamic model of the storage box;

[0070] 300: According to the obtained kinematic model and dynamic model, integrate to obtain the second-order differential simulation model of the complete storage box, and transform the second-order differential simulation model into two first-order differential simulation models based on modern control theory;

[0071] 400: Perform simulation based on the simulation model, set and update the simulation time according to whether the simulation results obtained by iterative solution converge, and end the simulation until convergent test results are obtained.

[0072] Figure 5 Schematically shows the selection of the rotation axis feature points P1, P2, P of the storage hopper in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention G selection.

[0073] Figure 6 Schematically shows the selection of the opening angle feature points P3, P4, P5, P6 of the storage hopper in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0074] Figure 7 Schematically shows the selection of the feature points P7, P8 of the fixed damping module in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0075] Figure 8 Schematically shows the central position point of the storage hopper on the rotation axis in an embodiment of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0076] As Figures 5 - 8 shown, in some embodiments, the selected feature points in the simulation method of the present invention include: two side suspension points P1 and P2 where the storage hopper is mounted on the support frame, the centroid point P G of the storage hopper, the rotation point P3 of the limiting mechanism of the storage hopper, the fixed points P4, P5, and P6 of the limiting mechanism of the support frame, and two side suspension points P7 and P8 for fixing the damping module, where P7 can represent the fixed end of the damping module and P8 can represent the movable end of the damping module.

[0077] In some embodiments, the above step 200 of building the kinematic model of the storage hopper includes: defining the coordinate system and building the opening angle model of the storage hopper.

[0078] In some specific embodiments, defining the coordinate system includes: defining the global earth coordinate system and / or the local coordinate system of the storage hopper, as well as defining the origin position and the positive direction of the coordinate system.

[0079] Among them, the global coordinate system adopts the vehicle coordinate system in Catia / UG, and its origin position and positive direction are the same as those of the vehicle coordinate system. The +y L axis direction is determined by the position of the rotation axis of the storage hopper, pointing from the driver's side of the vehicle to the co-driver's side, that is, from Figure 5 point P2 in to point P1 (points P1 and P2 are respectively the two side suspension points where the storage hopper is mounted on the support frame), the +z L axis direction is determined by the centroid point P G of the storage hopper and the vertical intersection point P L from the centroid point to the +y O axis (see Figure 8 point P O shown), and its positive direction points from the intersection point P O to P G , and the positive direction of the +x L axis is orthogonal to the +y L axis and the +z L axis, where the origin position is defined at the Figure 5 point P O shown.

[0080] In some specific embodiments, the global earth coordinate system can adopt the vehicle coordinate system X E -Y E -Z E in Catia / UG. The local coordinate system is x L -y L -z L L L L and the earth coordinate system YE The included angle is Φ, and the local coordinate system z L and the earth coordinate system Z E The included angle is γ, and the local coordinate system x L and the earth coordinate system X E The included angle is α, then the transformation matrix from the local coordinate system to the earth coordinate system is as follows:

[0081] From this transformation matrix, the position transformation of each position point in the local coordinate system to the vehicle's earth coordinate system can be obtained.

[0082] Figure 11 This is a schematic diagram of the calculation method for the maximum opening angle of the storage hopper in an implementation manner of the simulation method for testing the opening time of the vehicle storage box described in the present invention.

[0083] In some embodiments, when building the opening angle model of the storage hopper (or the maximum opening angle model of the storage hopper), the selected feature points may include as shown in Figure - Figure 8 shown: the rotation point P3 of the limiting mechanism of the storage hopper, and the fixed points P4, P5, and P6 of the limiting mechanism of the support frame.

[0084] When the storage hopper of the storage box is opened to the maximum angle, there will be a limiting module 5 on the support frame of the storage box to limit it (as Figure 1 shown). As Figure 11 shown, the fixed points P4, P5, and P6 form a limiting module plane. When the initial P3 point on the storage hopper rotates into the plane formed by the P4, P5, and P6 points, the rotation angle at this time is the maximum angle θ that the storage hopper can open max , and its intersection point in the limiting plane is P′3. See Figure 6 and Figure 11 .

[0085] Let the initial coordinate of point P3 be P 3_initial (x 3_initial ,y 3_initial ,z 3_initial ), the coordinate of point P4 is P4(x4, y4, z4), the coordinate of point P5 is P5(x5, y5, z5), the coordinate of point P6 is P6(x6, y6, z6), the perpendicular positive intersection point of the initial P3 point to the rotation axis of the storage hopper is P A (x A ,y A ,z A ), the coordinate of point P0 is P0(x0, y0, z0), then the position point coordinate P′3(x′3, y′3, z′3) of P′3 is solved by the following three equations:

[0086] (x - x A )2 +(y - y A ) 2 +(z - z A ) 2 =‖P A _P 3_initial ‖ 2

[0087] (x - x A )(x0 - x A )+(y - y A )(y0 - y A )+(z - z A )(z0 - z A )=0

[0088] ax + by + cz + d=0

[0089] where a = (y5 - y4)·(z6 - z4)-(y6 - y4)·(z5 - z4), b = (z5 - z4)·(x6 - x4)-(z6 - z4)·(x5 - x4),

[0090] c = (x5 - x4)·(y6 - y4)-(x6 - x4)·(y5 - y4), d = -a·x4 - b·y4 - c·z4

[0091] After obtaining the position coordinates of point P′3 by solving the above equation, using the vectors formed by point P A and point P 3_initial and point P′3 respectively, the vector included angle θ max can be directly solved. It should be noted that when there are two solution values, the smaller value should be taken as θ max .

[0092] In some embodiments, the building of the dynamic model of the storage box in step 200 of the simulation method described in the present invention includes: building the gravity moment model of the storage hopper and building the damping moment model of the damping module.

[0093] It should be noted that during the opening process of the storage hopper, the position of its center of mass P G and the position of the moving suspension point P8 of the damping module are both changing dynamically.

[0094] Figure 9 Schematic diagram of the dynamic position vector calculation method of the center of mass of the storage hopper in an embodiment of the simulation method for testing the opening time of the vehicle storage box described in the present invention.

[0095] Figure 10 Schematic diagram of the dynamic position vector calculation method of the suspension point of the damping module in an embodiment of the simulation method for testing the opening time of the vehicle storage box described in the present invention.

[0096] As Figure 9 and Figure 10 shown, let the centroid of the storage hopper and the suspension point of the damping module be at the position vector coordinates of P i when the opening angle of the storage hopper is θ Gi (x Gi , y Gi , z Gi ) and P 8i (x 8i , y 8i , z 8i ), then P Gi can be expressed as:

[0097]

[0098] where is the coordinate system transformation matrix, and P G_initial is the initial position coordinate of P G of the centroid point of the storage hopper.

[0099] For P 8i , if θ i ≤θ 8_initial ,

[0100]

[0101] Conversely, if θ i >θ 8_initial ,

[0102]

[0103] where P 8_initial is the initial position coordinate of the moving suspension point P8 of the damping module, θ 8_initial is the angle between the initial position of P 8_initial and the z L axis, and P B (x B [[ID=7�]], y B , z B ) is the position coordinate of the perpendicular positive intersection point from the initial P 8_initial point to the rotation axis of the storage hopper.

[0104] Figure 12 is a schematic diagram of the calculation method of the damping moment M damper of the damping module in an embodiment of the simulation method for testing the opening time of a vehicle storage box according to the present invention.

[0105] Figure 13 shows the algorithm flow of the damping moment of the damping module in an embodiment of the simulation method for testing the opening time of a vehicle storage box according to the present invention.

[0106] During the opening movement of the storage hopper, it is affected by the damping force of the damping module, generating a corresponding damping moment. The magnitude of the damping moment will directly affect whether the storage hopper opens too fast or too slow. Therefore, in some specific embodiments, the calculation of the damping moment includes the real-time calculation of the damping force and the real-time calculation of the lever arm size of the damping module on the storage hopper.

[0107] As Figure 13 shown, considering the influence of the dead travel size Δ damper in the production and manufacturing process of the damping module physical object, calculate the rotation angle size θ damper of the storage hopper corresponding to the dead travel according to the size of Δ damper . At the same time, calibrate the damping module to obtain the relationship characteristics between the damping force F damper and the damping movement speed V damper . On the other hand, as Figure 12 shown, from the CAD data of the storage box, the three-dimensional coordinates of the suspension feature points P7 and P8 at both ends of the damping module can be obtained. Among them, P7 is the fixed suspension point and P8 is the initial moving suspension point. The relationship between the damping speed V damper and the rotation angle θ i of the storage hopper, as well as the relationship between the lever arm L dampr of the damping module relative to the storage hopper and the rotation angle θ i of the storage hopper can be obtained.

[0108] Let the initial coordinates of point P8 be P8(x8, y8, z8), point P7 be P7(x7, y7, z7), and the perpendicular orthocenter of the initial P8 point to the rotation axis of the storage hopper be P B (x B , y B , z B ). See Figure 12 . For the damping speed V damper and the rotation angle θ i of the storage hopper, there is the following relationship: where sinψ i can be obtained by the coordinate values of the three points P7, P 8i and the rotation center P B . Among them, represents the angular velocity of the storage hopper.

[0109] For the lever arm L damper of the damping module relative to the storage hopper and the rotation angle θ i of the storage hopper, there is the following relationship: L damper = abs(‖P8_P B ‖·sinψ i ); where ψ i can be obtained by the cosine theorem of P7, P 8iand the rotation center P B The coordinate values of the three points are obtained.

[0110] Then when the storage hopper rotates at an angle of θ i : If θ i ≥θ damper , the damping torque M damper is 0, otherwise the damping torque is M damper = F damper ·L damper .

[0111] Figure 14 This is a schematic diagram of the calculation method of the gravitational torque M of the storage hopper in an embodiment of the simulation method for testing the opening time of a vehicle storage box according to the present invention. G Schematic diagram of the calculation method.

[0112] During the opening process of the storage hopper, the torque generated by its own weight is the driving force to open the storage hopper. The calculation of the gravitational torque includes determining the mass m L of the storage hopper and the position of the centroid P G , calculating the real-time moment arm of the gravity of the storage hopper. Refer to Figure 14 . According to the density of each component material of the storage box hopper, input it into the CAD data of the storage box, and the mass m L of the storage hopper and the position coordinates of the centroid P G can be obtained in Catia / UG.

[0113] Figure 15 Shows the algorithm flow of the gravitational torque of the storage hopper in an embodiment of the simulation method for testing the opening time of a vehicle storage box according to the present invention.

[0114] As Figure 14 shown, the moment arm L G of the gravitational torque and the rotation angle θ i of the storage hopper can be expressed as: L G =‖P G _P O ‖·sin(θ G_initial +θ i ), where θ G_initial represents the angle between the local coordinate system z L axis (the line connecting the centroid P G of the storage hopper and P O ) and the earth coordinate system z E .

[0115] Then when the rotation angle of the storage hopper is the gravitational torque M G is M G = m L g·L G, otherwise the damping moment is

[0116] Figure 16 It is a schematic diagram of the calculation method of the storage box assembly model in an implementation manner of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0117] As Figure 16 shown, based on the above module models, after integration, a second-order differential simulation model of the opening time of the storage box assembly can be obtained:

[0118]

[0119] where I y represents the moment of inertia of the storage bin around the rotation axis, which is a value obtained in the storage box CAD, represents the angular acceleration of the storage bin, g represents the acceleration due to gravity, m L represents the mass of the storage bin, L G represents the lever arm of the gravitational moment, F damper represents the damping force obtained by the damping module, L dampr represents the lever arm of the damping module relative to the storage bin.

[0120] In some preferred embodiments, in order to facilitate the iterative solution by the solver, the second-order differential simulation model can be transformed into two first-order differential simulation models; where let u1 = θ i , then the two first-order differential simulation models are: where represents the angular velocity of the storage bin, θ i represents the rotation angle of the storage bin.

[0121] Based on the above two first-order differential simulation models, through iterative solution, at least one of the following can be obtained: the opening time of the storage box, the opening angle, the opening angular velocity, the opening angular acceleration, the real-time relationship between at least one of the opening angle, the opening angular velocity, and the opening angular acceleration and the opening time, the relationship between at least one of the gravitational moment, the damping moment, and the lever arm of the storage box and the opening angle, the relationship between at least one of the gravitational moment, the damping moment, and the lever arm of the storage box and the opening time.

[0122] An implementation manner of the present invention also provides a simulation system for testing the opening time of a vehicle storage box. This system is a software or a computer and program that executes the above simulation method.

[0123] Figure 17 It shows a comparison chart of the simulation results and the test results based on the opening angle of the storage bin in an implementation manner of the simulation method for testing the opening time of the vehicle storage box according to the present invention.

[0124] Figure 18 A comparison chart showing simulation results and test results based on the angular acceleration of the storage compartment opening of a simulation method for testing the opening time of a vehicle storage box according to one embodiment of the present invention is shown.

[0125] Depend on Figure 17 and Figure 18 It can be seen that the simulation method for testing the opening time of a vehicle storage box according to the present invention can well simulate the vehicle storage box opening test.

[0126] In addition, the combination of the various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them.

[0127] It should also be noted that the above-listed embodiments are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above-listed embodiments. Similar variations or modifications that can be directly derived from or easily conceived by those skilled in the art based on the disclosure of the present invention should fall within the scope of protection of the present invention.

Claims

1. A simulation method for testing the opening time of a vehicle storage box, wherein the storage box comprises a support frame, a storage hopper that can be opened relative to the support frame, and a damping module; characterized in that: The simulation method comprises the steps of: 100: Based on the CAD data of the storage box and the material density of the storage bucket, extract the three-dimensional position coordinates of the selected feature points, the mass of the storage bucket, and the moment of inertia of the storage bucket; 200: Based on the three-dimensional position coordinates of the selected feature points, the mass of the storage bucket, and the moment of inertia of the storage bucket, a kinematic model of the storage bucket and a dynamic model of the storage box are constructed respectively; 300: Based on the obtained kinematic model and dynamic model, a complete second-order differential simulation model of the storage box is obtained by integration; 400: Perform simulation based on the simulation model.

2. The simulation method according to claim 1, wherein: Step 300 also includes: converting the second-order differential simulation model into two first-order differential simulation models.

3. The simulation method according to claim 1, wherein: Step 400 includes: during the simulation, setting and updating the simulation time according to whether the simulation result obtained through iterative solution converges, and terminating the simulation until a converged test result is obtained.

4. The simulation method according to claim 1, wherein: In step 200 , building a kinematic model of the storage bucket includes defining a coordinate system and building an opening angle model of the storage bucket.

5. The simulation method according to claim 1, wherein: In step 200, building a dynamic model of the storage box includes building a gravity moment model of the storage bucket and building a damping moment model of the damping module.

6. The simulation method according to claim 1, wherein: The selected characteristic points include: two side suspension points where the storage bucket is installed on the support frame, the center of mass of the storage bucket, the rotation point of the limiting mechanism of the storage bucket, the fixing point of the limiting mechanism of the support frame, and two side suspension points for fixing the damping module.

7. The simulation method according to claim 1, wherein: The second-order differential simulation model is constructed as: Among them I y represents the moment of inertia of the storage hopper, represents the angular acceleration of the storage bucket, g represents the acceleration due to gravity, m L Indicates the mass of the storage hopper, L G The moment arm representing the gravitational moment, F damper Represents the damping force obtained by the damping module, L damper Indicates the lever arm of the damping module relative to the storage bucket.

8. The simulation method according to claim 7, wherein: Step 300 also includes: converting the second-order differential simulation model into two first-order differential simulation models; wherein u1=θ i , Then the two first-order differential simulation models are: in represents the angular velocity of the storage hopper, θ i Indicates the rotation angle of the storage hopper.

9. The simulation method according to claim 1, wherein: In step 400, at least one of the following items is obtained based on simulation: the opening time, opening angle, opening angular velocity, opening angular acceleration of the storage box, the real-time relationship between the opening time and at least one of the opening angle, opening angular velocity, and opening angular acceleration, the relationship between the opening angle and at least one of the gravity moment, damping moment, and lever arm of the storage box, and the relationship between the opening time and at least one of the gravity moment, damping moment, and lever arm of the storage box.

10. A simulation system for testing the opening time of a vehicle storage box, which executes the simulation method according to any one of claims 1 to 9.

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