Simulation opening and closing control method, device and equipment of vehicle front cover model and medium

Abstract

The application discloses a simulation opening and closing control method, device and equipment of a vehicle front cover model and a medium. The method comprises the following steps: based on the geometric relationship of a four-bar linkage hinge of the vehicle front cover model, and according to a first rotation angle of a first connecting rod in the four-bar linkage hinge, the first position coordinates of a first hard point and the second position coordinates of a second hard point in a rod part are calculated, and the front cover body part is transformed to an opening position or a closing position corresponding to the first rotation angle through a three-point alignment geometric transformation method; the opening and closing limit positions of the vehicle front cover model are automatically determined by iteratively adjusting the first rotation angle and detecting whether the rod part is interfered, and the iteration is stopped when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and the first rotation angle corresponding to the stop of the iteration is determined as the limit opening angle or the limit closing angle of the vehicle front cover model. The technical scheme of the application can improve the simulation opening and closing control efficiency and the model precision of the front cover.

Description

Technical Field

[0001] This application relates to the field of vehicle simulation control technology, specifically to a simulation opening and closing control method, device, equipment, and medium for a vehicle front hood model. Background Technology

[0002] The front hood, as a key component of the vehicle body, is crucial to the structural performance of the vehicle and pedestrian safety. Simulation of the front hood structure requires loading and solving the problem from its closed state to a certain angle. Currently, there are two main technical solutions: one is to use mechanical simulation software, but this method requires rebuilding the model, resulting in a long modeling cycle and mesh consistency issues; the other is to manually adjust the position of the front hood model, but this method is time-consuming and labor-intensive, and can easily lead to deviations between the open position of the front hood and the actual state, resulting in inaccurate simulation results. Summary of the Invention

[0003] In view of the above problems, this application provides a simulation opening and closing control method, device, equipment and medium for a vehicle front cover model, which solves the problem that the prior art cannot automatically simulate the opening and closing control of a vehicle front cover model.

[0004] According to one aspect of the embodiments of this application, a simulation opening and closing control method for a vehicle front hood model is provided, the method comprising:

[0005] The vehicle front hood model is divided into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and a front hood main body part that is to be spatially transformed.

[0006] Based on the geometric relationship of the four-bar hinge of the vehicle front hood model, and according to the first rotation angle of the first link in the four-bar hinge, the first position coordinates of the first hard point and the second position coordinates of the second hard point in the link part are calculated.

[0007] Based on the first position coordinates and the second position coordinates, the front cover body is transformed to the open or closed position corresponding to the first rotation angle using a three-point aligned geometric transformation method.

[0008] By iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod part, the limit position of the vehicle front cover model is automatically determined. The iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs. The first rotation angle corresponding to the stop of iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

[0009] In an alternative approach, the step of calculating the first position coordinates of the first hard point and the second position coordinates of the second hard point in the link section based on the geometric relationship of the four-bar hinge of the vehicle hood model and according to the first rotation angle of the first link in the four-bar hinge, further includes:

[0010] Based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point, calculate the first position coordinates of the first hard point;

[0011] Based on the first position coordinates and the first rod length between the first hard point and the second hard point, construct the first circle equation;

[0012] Based on the coordinates of the second fixed point in the four-bar linkage and the length of the second link between the second fixed point and the second hard point, a second circle equation is constructed.

[0013] By simultaneously solving the equations of the first and second circles, the coordinates of the two candidate positions of the second hard point can be obtained.

[0014] The second position coordinate of the second hard point is determined from the two candidate position coordinates based on the angle between the initial position vector of the second hard point and the vectors corresponding to the two candidate position coordinates.

[0015] In an alternative approach, the step of transforming the front cover body portion to an open or closed position corresponding to the first rotation angle using a three-point aligned geometric transformation method based on the first and second position coordinates further includes:

[0016] Based on the first rotation angle and the symmetry of the four-bar hinge, the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link section are calculated.

[0017] Three non-coplanar target points are selected from the first and second position coordinates located on the left side of the rod portion, and the third and fourth position coordinates located on the right side of the rod portion;

[0018] Select three non-coplanar source points corresponding to the three non-coplanar target points in the initial state of the front cover main body;

[0019] The transformation matrix is ​​calculated based on the three non-coplanar source points and the three non-coplanar target points, and the transformation matrix is ​​applied to transform the front cover body from the initial state to the open or closed position corresponding to the first rotation angle.

[0020] In one alternative approach, the step of automatically determining the limit position of the vehicle front hood model by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the stop iteration as the limit opening angle of the vehicle front hood model, further includes:

[0021] Set the initial angle and preset increment of the first rotation angle;

[0022] Based on the current first rotation angle, perform position calculation and transformation operation for the front cover opening, and detect whether the rod part interferes after the transformation operation;

[0023] When no interference occurs, the first rotation angle is increased by the preset step size, and the calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0024] When interference occurs, the preset increment step size is reduced according to the dichotomy method, and the first rotation angle is reduced according to the reduced preset increment step size. The calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0025] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit opening angle of the vehicle front cover model.

[0026] In one alternative approach, the step of automatically determining the limiting position of the vehicle front hood model's closure by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the point where iteration stops as the limiting closure angle of the vehicle front hood model, further includes:

[0027] Set the initial angle and preset reduction step size for the first rotation angle;

[0028] Based on the current first rotation angle, perform position calculation and transformation operation for front cover closure, and detect whether interference occurs in the rod part after the transformation operation;

[0029] When no interference occurs, the first rotation angle is reduced according to the preset step size, and the calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0030] When interference occurs, the preset reduction step size is reduced according to the dichotomy method, and the first rotation angle is increased according to the reduced preset reduction step size. The calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0031] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit closing angle of the vehicle front cover model.

[0032] In an alternative approach, the step of calculating the first position coordinates of the first hard point based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point further includes:

[0033] Based on the geometric relationship of the first hard point rotating around the first fixed point in a preset plane, the first position coordinates of the first hard point are calculated according to the first rotation angle, the coordinates of the first fixed point, and the initial coordinates of the first hard point, wherein the rotation axis is an axis perpendicular to the preset plane and passing through the first fixed point.

[0034] In an alternative approach, the step of calculating the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link portion based on the first rotation angle and the symmetry of the four-bar hinge further includes:

[0035] Based on the first rotation angle and the symmetry of the four-bar hinge, the first position coordinates of the first hard point are obtained by mirror transformation to obtain the third position coordinates of the third hard point, and the second position coordinates of the second hard point are obtained by mirror transformation to obtain the fourth position coordinates of the fourth hard point;

[0036] The plane of symmetry for the mirror transformation is the longitudinal plane of symmetry of the vehicle front hood model.

[0037] According to another aspect of the embodiments of this application, a simulation opening and closing control device for a vehicle front hood model is provided, comprising:

[0038] The partitioning module is used to divide the vehicle front cover model into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and a front cover main body part that needs to be spatially transformed.

[0039] The calculation module is used to calculate the first position coordinates of the first hard point and the second position coordinates of the second hard point in the rod part based on the geometric relationship of the four-bar hinge of the vehicle front hood model and according to the first rotation angle of the first link in the four-bar hinge.

[0040] The transformation module is used to transform the front cover body part to an open or closed position corresponding to the first rotation angle based on the first position coordinates and the second position coordinates using a three-point aligned geometric transformation method.

[0041] The control module is used to automatically determine the limit position of the vehicle front cover model by iteratively adjusting the first rotation angle and detecting whether the rod part interferes, until the iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, and the first rotation angle corresponding to the stop iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

[0042] According to another aspect of the embodiments of this application, a simulation opening and closing control device for a vehicle front hood model is provided, comprising:

[0043] Controller;

[0044] The memory is used to store one or more programs, which, when executed by the controller, enable the controller to implement the simulation opening and closing control method of the vehicle front cover model of this application.

[0045] According to another aspect of the embodiments of this application, a computer-readable storage medium is provided, wherein the storage medium stores at least one executable instruction, which, when executed on a simulation opening and closing control device / equipment for a vehicle front hood model, causes the simulation opening and closing control device / equipment for the vehicle front hood model to perform the operation of the simulation opening and closing control method for the vehicle front hood model of this application.

[0046] This embodiment of the application divides the vehicle front cover model into a fixed part connected to the vehicle body, a rod part rotating around the hinge center, and a front cover main body part to be spatially transformed. Based on the geometric relationship of the four-bar hinge of the vehicle front cover model, and according to the first rotation angle of the first link in the four-bar hinge, the first position coordinates of the first hard point and the second position coordinates of the second hard point in the rod part are calculated. Based on the first position coordinates and the second position coordinates, the front cover main body part is transformed to the open or closed position corresponding to the first rotation angle through a three-point alignment geometric transformation method. By iteratively adjusting the first rotation angle and detecting whether the rod part interferes, the limit position of the vehicle front cover model opening or closing is automatically determined until the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, and the iteration stops. The first rotation angle corresponding to the stop of iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model. This can solve the problems of time-consuming modeling, laborious manual adjustment, and insufficient accuracy of the vehicle front cover model, and improve the efficiency and accuracy of the front cover simulation opening and closing control.

[0047] The above description is merely an overview of the technical solutions of the embodiments of this application. In order to better understand the technical means of the embodiments of this application and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of this application more obvious and understandable, specific implementation methods of this application are described below. Attached Figure Description

[0048] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0049] Figure 1 A flowchart illustrating an embodiment of the simulation opening and closing control method for a vehicle front hood model provided in this application is shown.

[0050] Figure 2 This is one of the schematic diagrams of a vehicle front hood model.

[0051] Figure 3 This is the second schematic diagram of a vehicle front hood model.

[0052] Figure 4 This is one of the schematic diagrams illustrating the principle of determining the extreme position during the opening of the front cover.

[0053] Figure 5 This is the second schematic diagram illustrating the principle of determining the extreme position during the opening of the front cover.

[0054] Figure 6 A schematic diagram of an embodiment of the simulation opening and closing control device for the vehicle front hood model provided in this application is shown.

[0055] Figure 7 A schematic diagram of an embodiment of the simulation opening and closing control device for the vehicle front hood model provided in this application is shown.

[0056] Explanation of reference numerals in the attached figures:

[0057] 1. Hinge fixing part, 2. Hinge rotating part, 3. Front cover main body part, 4. Opening limit, 5. Closing limit. Detailed Implementation

[0058] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0059] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0060] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0061] In this application, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0062] The front hood, as a key component of the vehicle body, is crucial to the structural performance of the vehicle and pedestrian safety. Simulation of the front hood structure requires loading and solving the problem from its closed state to a certain angle. Currently, there are two main technical solutions: one is to use mechanical simulation software, but this method requires rebuilding the model, resulting in a long modeling cycle and mesh consistency issues; the other is to manually adjust the position of the front hood model, but this method is time-consuming and labor-intensive, and can easily lead to deviations between the open position of the front hood and the actual state, resulting in inaccurate simulation results. Therefore:

[0063] Figure 1 A flowchart illustrating an embodiment of the simulation opening and closing control method for a vehicle front hood model provided in this application is shown. This method is executed by a simulation opening and closing control device for the vehicle front hood model. Please refer to... Figure 1 As shown, the method includes the following steps:

[0064] S110: Divide the vehicle front cover model into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and the main body of the front cover to be transformed in space 3.

[0065] The vehicle front hood model refers to a digital model of the vehicle front hood used for simulation analysis, composed of finite element meshes, including hinges, panels, and connecting components. The fixed part refers to the portion of the vehicle front hood model that is connected to the vehicle body side via hinges and remains in a fixed position throughout the opening and closing process. The hinge center refers to the geometric center point around which each link in a four-bar hinge rotates. The link part refers to the movable links that constitute the four-bar hinge in the vehicle front hood model. The main body part 3 of the front hood refers to the main panel portion of the vehicle front hood model, excluding the fixed part and the link part, that needs to change its spatial position with the hinge movement.

[0066] Specifically, such as Figure 2 As shown, based on the geometric structure of the vehicle front hood model, fixed points O1 and O2 connected to the side hinges of the vehicle body are identified, and fixed points O1 and O2 and their associated components are divided into fixed parts; connecting rods O1A and O2B that rotate around the hinge center are identified, and connecting rods O1A and O2B and their moving components are divided into rod parts; the main panel of the front hood and the components connected to the rod parts are identified, including the connected RB2 units (Rigid Body Element Type 2, two-dimensional rigid body element), and the main panel of the front hood and the connecting components are divided into the main body part 3 of the front hood. The main body part 3 of the front hood needs to change its position through spatial transformation during the opening and closing process.

[0067] S120: Based on the geometric relationship of the four-bar hinge of the vehicle front hood model, and according to the first rotation angle of the first link in the four-bar hinge, calculate the first position coordinate of the first hard point and the second position coordinate of the second hard point in the link part.

[0068] In this context, a four-bar linkage refers to a planar motion mechanism formed by four links connected through hinge points. Geometric relationships refer to the spatial dimensions and motion constraints between the components of the four-bar linkage. The first link is the link in the four-bar linkage that connects to a fixed point on the side of the vehicle body and serves as the motion input reference. The first rotation angle is the angle value of the first link rotating around its hinge center. The first hard point is a feature point located at the end of the first link in the linkage section. The first position coordinates are the spatial coordinate values ​​of the first hard point after the first link has rotated a certain angle. The second hard point is a feature point located at the end of the second link in the linkage section.

[0069] S130: Based on the first position coordinates and the second position coordinates, the front cover body part 3 is transformed to the open or closed position corresponding to the first rotation angle through a three-point aligned geometric transformation method.

[0070] The three-point alignment geometric transformation method refers to calculating the transformation matrix using the coordinate correspondence of three non-coplanar points. For example, in ANSA (Advanced Numerical Simulation Analysis) software, the Transform function can be used to automatically calculate the transformation matrix by selecting three source points and three target points. The open position refers to the spatial position of the vehicle front hood model relative to the vehicle body when it is in an open state. The closed position refers to the spatial position of the vehicle front hood model relative to the vehicle body when it is in a closed state.

[0071] S140: By iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod part, the limit position of the vehicle front cover model is automatically determined until the iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs. The first rotation angle corresponding to the stop iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

[0072] Iterative adjustment refers to the optimization process of gradually approaching the target value through iterative calculations; for example, by repeatedly adjusting the first rotation angle and detecting interference, the maximum opening angle of the front hood is gradually approached. The limit position refers to the position corresponding to the extreme state that the vehicle front hood model can reach during opening and closing; for example, the critical position where the front hood is about to interfere with other parts of the vehicle body but has not yet made contact when it is open. The adjustment amount refers to the amount of parameter change between two adjacent iterations. The set tolerance refers to the threshold for determining convergence during the iteration process; the default setting is 0.1°, but it can be adjusted according to actual conditions, and no restriction is set here. The limit opening angle refers to the maximum angle at which the vehicle front hood model can be safely opened. The limit closing angle refers to the minimum angle at which the vehicle front hood model can be completely closed.

[0073] The technical solution of this embodiment can solve the problems of time-consuming modeling of vehicle front cover models, laborious manual adjustment, and insufficient accuracy, and improve the efficiency of front cover simulation opening and closing control and model accuracy.

[0074] In an alternative embodiment, S120 further includes:

[0075] Based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point, calculate the first position coordinates of the first hard point.

[0076] The coordinates of the first fixed point refer to the coordinates of the rotation center of the first link in the four-bar linkage; for example, the coordinates of point O1 in the left hinge are (1200, 500, 800) mm. The initial coordinates of the first hard point refer to the coordinates of the first hard point when the vehicle front hood model is in the closed state; for example, the coordinates of the first hard point A in the closed state are (1350, 500, 850) mm.

[0077] Based on the first position coordinates and the first rod length between the first hard point and the second hard point, a first circle equation is constructed.

[0078] Here, the first rod length refers to the initial distance between the first hard point A and the second hard point B. The first circle equation refers to the mathematical equation of the circle established with the first hard point A' after transformation as the center and the first rod length R1 as the radius.

[0079] Specifically, the X coordinate X is based on the first position coordinate A' of the first hard point A. A 'and Z coordinates Z A ', and the first rod length R1 between the first hard point A and the second hard point B, wherein the first rod length R1 is expressed by the formula R1²=(X B -X A )²+(Z B -Z A X is calculated as follows: B and Z B Let X and Z be the initial X and Z coordinates of the second hard point B. A and Z A Let A be the initial X and Z coordinates of the first hard point; construct the equation of the first circle in the OXZ plane, which is (XX... A ')²+(ZZ A ') 2 =R1 2 For example, based on the first hard point A (1350, 500, 850) mm and the second hard point B (1400, 500, 750) mm, using formula R1 2 =(X B -X A ) 2 +(Z B -Z A ) 2 The calculated length R1 of the first rod is 200 mm. When the first rotation angle θ1 is 15°, the calculated coordinates of A' are (1335.2, 500, 865.8) mm, and the equation of the first circle is (X - 1335.2). 2 +(Z-865.8) 2 =200 2 .

[0080] Based on the coordinates of the second fixed point in the four-bar linkage and the length of the second rod between the second fixed point and the second hard point, the equation of the second circle is constructed.

[0081] The coordinates of the second fixed point refer to the coordinates of the rotation center of the second link in the four-bar linkage; for example, the coordinates of point O2 in the left hinge are (1450, 500, 700) mm. The second link length refers to the initial distance between the second fixed point O2 and the second hard point B. The second circle equation refers to the mathematical equation of the circle established in the motion plane OXZ with the second fixed point O2 as the center and the second link length R2 as the radius.

[0082] Specifically, based on the coordinates (X2, Y2, Z2) of the second fixed point O2 in the four-bar linkage and the second link length R2 between the second fixed point O2 and the second hard point B, where the second link length R2 is obtained through formula R2 2 =(X B -X2) 2 +(Z B -Z2) 2 Calculations show that X B and Z B Let the initial X and Z coordinates of the second hard point B be denoted as ; construct the equation of the second circle in the OXZ plane, the equation of the second circle is ((XX B ') 2 +(ZZ B ') 2 =R2 2 For example, based on the coordinates of the second fixed point O2 (1450, 500, 700) mm and the coordinates of the second hard point B (1400, 500, 750) mm, using formula R2 2 =(X B -X2) 2 +(Z B -Z2) 2 The calculated length R2 of the second rod is 180 mm. The equation of the second circle, centered at O2(1450, 500, 700) mm, is (X-1450). 2 +(Z-700) 2 =180 2 .

[0083] By simultaneously solving the equations of the first and second circles, the coordinates of the two candidate positions of the second hard point can be obtained.

[0084] The two candidate position coordinates refer to the two mathematical solutions obtained by simultaneously solving the first and second circle equations, which correspond to the two possible new positions B' and B'' of the second hard point B. The simultaneous solution process includes: subtracting the first and second circle equations to eliminate the quadratic term, resulting in a linear equation about X and Z; substituting this linear equation back into the first or second circle equation to eliminate one variable (e.g., Z), resulting in a quadratic equation about another variable (e.g., X); solving this quadratic equation to obtain two solutions for the variable (e.g., X); substituting these two solutions into the linear equation about X and Z to obtain the corresponding values ​​of the variable (e.g., X), thus obtaining two sets of solutions for X and Z, i.e., the two candidate position coordinates. For example, through the above solution process, two candidate position coordinates of B can be obtained, such as (1385.3, 500, 765.7) mm and (1395.1, 500, 734.2) mm.

[0085] The second position coordinate of the second hard point is determined from the two candidate position coordinates based on the angle between the initial position vector of the second hard point and the vectors corresponding to the two candidate position coordinates.

[0086] The initial position vector of the second hard point refers to the spatial vector pointing from the second fixed point O2 to the initial position of the second hard point B; for example, the vector pointing from O2 (1450, 500, 700) mm to B (1400, 500, 750) mm is (-50, 0, 50) mm. The vectors corresponding to the two candidate position coordinates refer to the directed line segments pointing from the second fixed point O2 to the two candidate position coordinates B' and B''; for example, the vector pointing from O2 to the candidate position B' (1385.3, 500, 765.7) mm is (-64.7, 0, 65.7) mm.

[0087] Specifically, based on the angle between the initial position vector O2B of the second hard point B and the vector O2B' corresponding to the candidate position coordinate B', the angle between vectors O2B and O2B' is calculated. Since the vectors O2B' and O2B'' corresponding to the two candidate position coordinates B' and B'' are centrally symmetric about the second fixed point O2, the sum of the angle between vectors O2B and O2B' and the angle between vectors O2B and O2B'' is 180 degrees. When the angle between vectors O2B and O2B' is less than 90 degrees, it indicates that B' and B are on the same side of the movement path, and candidate position coordinate B' is selected as the second position coordinate of the second hard point. When the angle between vectors O2B and O2B' is greater than 90 degrees, it indicates that B' and B are on opposite sides of the movement path, and candidate position coordinate B'' is selected as the second position coordinate of the second hard point.

[0088] Among the above-mentioned optional methods, the accuracy and efficiency of hard point location calculation can be further improved by constructing a system of circle equations to solve for the hard point location and selecting candidate points in combination with the initial vector direction.

[0089] In an alternative embodiment, S130 further includes:

[0090] Based on the first rotation angle and the symmetry of the four-bar hinge, the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link are calculated.

[0091] The symmetry of the four-bar linkage refers to the characteristic that the left and right hinges of the vehicle's front hood are symmetrical about the longitudinal plane; for example, the left and right hinges are symmetrical about the XOZ plane and have the same motion law. The third hard point refers to a feature point located at the end of the first link of the right hinge in the linkage section; for example, the coordinates of point C in the right hinge, symmetrical to point A on the left, are (1350, -500, 850) mm in the initial state. The third position coordinates refer to the spatial coordinates of the third hard point after the right hinge has moved; for example, when the first rotation angle θ1 is 15°, the coordinates of C' obtained through mirror transformation are (1335.2, -500, 865.8) mm. The fourth hard point refers to a feature point located at the end of the second link of the right hinge in the linkage section; for example, the coordinates of point D in the right hinge, symmetrical to point B on the left, are (1400, -500, 750) mm in the initial state. The fourth position coordinate refers to the spatial coordinate value of the fourth hard point after the right hinge moves; for example, when the first rotation angle θ1 is 15°, the D' coordinates obtained by mirror transformation are (1385.3, -500, 765.7) mm.

[0092] Specifically, the first position coordinates (X) of the first hard point A on the left side, calculated based on the first rotation angle. A ',Y A ',Z A ') and the second position coordinates (X) of the second hard point B on the left. B ',Y B ',Z B '), and the symmetry of the four-bar linkage, the third position coordinates of the third hard point C on the right and the fourth position coordinates of the fourth hard point D on the right are calculated through mirror transformation; the mirror transformation is performed along the longitudinal symmetry plane XOZ plane of the vehicle front hood model; the X coordinate of the third position coordinate is equal to the X coordinate of the first position coordinate. A The Z-coordinate of the third position is equal to the Z-coordinate of the first position. A The Y-coordinate of the third position is equal to the Y-coordinate of the first position. A The negative value of '; the X-coordinate of the fourth position is equal to the X-coordinate of the second position. BThe Z-coordinate of the fourth position is equal to the Z-coordinate of the second position. B The Y-coordinate of the fourth position is equal to the Y-coordinate of the second position. B The negative value of '.

[0093] Three non-coplanar target points are selected from the first and second position coordinates located on the left side of the rod portion, and the third and fourth position coordinates located on the right side of the rod portion.

[0094] Among them, non-coplanar target points refer to three points that are not on the same plane selected from the position coordinates of the left and right hard points; for example, selecting three points A', B', and C' from A', B', C', and D' as the transformation target points.

[0095] Select three non-coplanar source points corresponding to the three non-coplanar target points in the initial state of the front cover body part 3.

[0096] The initial state refers to the original state of the vehicle front hood model when it is in the closed position; for example, all components of the front hood are in their designed installation positions, and each hard point is in its initial coordinate value. The non-coplanar source points refer to three non-coplanar points selected in the initial state that correspond to the target points; for example, initial points A, B, and C corresponding to target points A', B', and C' are selected in the closed state.

[0097] Specifically, based on the selection of three non-coplanar target points, three non-coplanar source points are selected in the initial state of the vehicle front cover model; the three non-coplanar source points correspond to the three non-coplanar target points respectively, and the three non-coplanar source points are the initial coordinates (X, X, Y) of the first hard point A. A ,Y A Z A ), the initial coordinates (X) of the second hard point B B ,Y B Z B ) and the initial coordinates (X) of the third hard point C C ,Y C Z C ), where the first hard point A, the second hard point B, and the third hard point C are not coplanar in the initial state.

[0098] The transformation matrix is ​​calculated based on the three non-coplanar source points and the three non-coplanar target points, and the transformation matrix is ​​applied to transform the front cover body part 3 from the initial state to the open or closed position corresponding to the first rotation angle.

[0099] The transformation matrix refers to a 4×4 homogeneous transformation matrix that transforms the source coordinate system to the target coordinate system; for example, the transformation matrix T, which includes rotation and translation parameters, is calculated using three source points and three target points.

[0100] Specifically, such as Figure 3 As shown, the transformation matrix is ​​automatically calculated using the three-point alignment method of ANSA software based on three non-coplanar source points and three non-coplanar target points. The transformation matrix is ​​calculated based on the coordinates of the three non-coplanar source points and the coordinates of the three non-coplanar target points. The calculated transformation matrix is ​​applied to transform all nodes of the front cover body 3 from the initial state to the open or closed position corresponding to the first rotation angle. Figure 3 The car cover model includes: a hinged fixed part 1 connected to the car body, a hinge rotating part 2 that rotates around the hinge center, and a front cover main body part 3 to be transformed in space. Figure 3 The opening limit 4 and closing limit 5 in the figure correspond to the limit positions of the vehicle front cover model for opening and closing, which are determined by iteratively adjusting the first rotation angle and detecting the interference of the rod part.

[0101] In the above-mentioned optional methods, based on the three-point aligned geometric transformation, the transformation matrix is ​​calculated by selecting non-coplanar source points and target points to achieve precise transformation of the front cover body and improve the opening and closing control accuracy and efficiency.

[0102] In one alternative approach, the step of automatically determining the limit position of the vehicle front hood model by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the stop iteration as the limit opening angle of the vehicle front hood model, further includes:

[0103] Set the initial angle and preset increment step of the first rotation angle.

[0104] The initial angle refers to the initial value of the first rotation angle set at the start of the iteration process; for example, the first rotation angle θ1 set when starting to find the limit opening angle is 5°. The preset increment step size refers to the increment step size of the first rotation angle when no interference occurs during the opening process; for example, increasing by 5° each time for tentative opening.

[0105] Based on the current first rotation angle, perform position calculation and transformation operation for the front cover opening, and detect whether interference occurs in the rod part after the transformation operation.

[0106] The calculation step for the opening position of the front cover specifically refers to the content in S120, and the transformation operation specifically refers to the content in S130.

[0107] When no interference occurs, the first rotation angle is increased by the preset step size, and the calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0108] When interference occurs, the preset increment step size is reduced according to the dichotomy method, and the first rotation angle is reduced according to the reduced preset increment step size. The calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0109] The binary search method refers to a numerical optimization method that halves the search interval each time; for example, after interference occurs, the step size is halved to 2.5° for reverse search.

[0110] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit opening angle of the vehicle front cover model.

[0111] The adjustment amount of the first rotation angle refers to the absolute value of the change in the first rotation angle between two adjacent iterations; for example, from 25° in the nth iteration to 22.5° in the (n+1)th iteration, the adjustment amount is 2.5°.

[0112] like Figure 4 As shown, the process of automatically determining the limit position of the vehicle front hood model by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod part is as follows: Figure 4 (1) shows the state in which the connecting rod O1A interferes with the opening limit 4 after rotating by the first rotation angle θ around the hinge center; Figure 4 (2) shows the state in which the first rotation angle is adjusted in the opposite direction to θ / 2 after the adjustment step size is reduced by the dichotomy method and no interference occurs with the opening limit 4; Figure 4 (3) shows the state where the first rotation angle is adjusted to θ / 4 in the positive direction and there is still no interference with the opening limit 4. By repeating this process, the adjustment of the first rotation angle is stopped when it is less than the set tolerance and there is no interference with the opening limit 4, so as to accurately determine the limit opening angle of the vehicle front cover model.

[0113] like Figure 5As shown, an initial angle θ0 and an acceptable angle tolerance α are set for the first rotation angle. Based on the current first rotation angle θ0, the position calculation and transformation operation of the front hood opening are performed, and the penetration interference of the rod part after the transformation operation is detected. When no penetration interference occurs, the opening angle θ0 remains unchanged. When penetration interference occurs, the opening angle θ0 is adjusted to θ0 / 2. Then, it is determined whether the adjusted opening angle θ0 is less than the angle tolerance α. If θ0 is less than α, the iteration stops and the process ends. If θ0 is not less than α, the opening angle θ0 is adjusted to θ0 / 2 again, and the position calculation, transformation operation and interference detection are repeated until the adjustment amount of the first rotation angle is less than the set tolerance α and no interference occurs. The iteration stops when the first rotation angle stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit opening angle of the vehicle front hood model. The above process dynamically adjusts the angle step size through a bisection method to achieve accurate positioning of the limit position of the front hood opening.

[0114] In the above-mentioned optional methods, the rotation angle is further adjusted iteratively and interference is detected. Combined with step size adjustment and bisection method optimization, the limit opening angle of the front cover is efficiently determined, thereby improving the simulation control efficiency.

[0115] In one alternative approach, the step of automatically determining the limiting position of the vehicle front hood model's closure by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the point where iteration stops as the limiting closure angle of the vehicle front hood model, further includes:

[0116] Set the initial angle and preset reduction step size for the first rotation angle.

[0117] The preset reduction step size refers to the decreasing step size of the first rotation angle when no interference occurs during the closing process; for example, reducing by 5° each time for trial closing.

[0118] Based on the current first rotation angle, perform position calculation and transformation operation for the front cover to close, and detect whether interference occurs in the rod part after the transformation operation.

[0119] When no interference occurs, the first rotation angle is reduced according to the preset step size, and the calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0120] When interference occurs, the preset reduction step size is reduced according to the dichotomy method, and the first rotation angle is increased according to the reduced preset reduction step size. The calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0121] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit closing angle of the vehicle front cover model.

[0122] Among the above-mentioned optional methods, a strategy of reducing the step size and using the bisection method is further adopted to accurately locate the limit angle of the front cover closure, thereby enhancing the accuracy and reliability of the simulation opening and closing control.

[0123] In an alternative approach, the step of calculating the first position coordinates of the first hard point based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point further includes:

[0124] Based on the geometric relationship of the first hard point rotating around the first fixed point in a preset plane, the first position coordinates of the first hard point are calculated according to the first rotation angle, the coordinates of the first fixed point, and the initial coordinates of the first hard point, wherein the rotation axis is an axis perpendicular to the preset plane and passing through the first fixed point.

[0125] The preset plane refers to the theoretical motion plane of the four-bar linkage; for example, the OXZ plane determined by the four points O1, A, B, and O2 of the left hinge.

[0126] Specifically, based on the geometric relationship of the first hard point A rotating around the first fixed point O1 in the preset plane OXZ, according to the first rotation angle θ1, the coordinates (X1, Y1, Z1) of the first fixed point O1, and the initial coordinates (X1, Y1, Z1) of the first hard point A, A ,Y A Z A ), calculate the first position coordinates (X) of the first hard point A. A ',Y A ',Z A The formula for calculating the first position coordinate is X. A '=(X A -X1)cosθ1+(Z A -Z1)sinθ1+X1,Y A '=Y A Z A '=-(X A -X1)sinθ1+(Z A -Z1)cosθ1+Z1; The axis of rotation is the axis perpendicular to the OXZ plane and passing through the first fixed point O1.

[0127] Among the above-mentioned optional methods, the calculation of the hard point position is further simplified based on the geometric relationship of the hard point rotation around the fixed point, thereby improving the simulation efficiency and ensuring the model accuracy.

[0128] In an alternative approach, the step of calculating the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link portion based on the first rotation angle and the symmetry of the four-bar hinge further includes:

[0129] Based on the first rotation angle and the symmetry of the four-bar hinge, the first position coordinates of the first hard point are obtained by mirror transformation to obtain the third position coordinates of the third hard point, and the second position coordinates of the second hard point are obtained by mirror transformation to obtain the fourth position coordinates of the fourth hard point; the symmetry plane of the mirror transformation is the longitudinal symmetry plane of the vehicle front cover model.

[0130] Among them, mirror transformation refers to the coordinate transformation method of generating mirror-symmetric points about a plane of symmetry. The longitudinal plane of symmetry refers to the reference plane that is symmetrical about the left and right sides of the vehicle front hood model; for example, the XOZ plane in the vehicle coordinate system, that is, the plane where Y=0.

[0131] Among the above optional methods, the mirror transformation is further used to calculate the position of symmetrical hard points, optimize the application of four-link symmetry, and improve the transformation efficiency and the consistency of the front cover model mesh.

[0132] Figure 6 A schematic diagram of an embodiment of the simulation opening and closing control device for the vehicle front hood model provided in this application is shown. Please refer to... Figure 6 As shown, the device 300 includes: a partitioning module 310, a calculation module 320, a transformation module 330, and a control module 340.

[0133] The dividing module 310 is used to divide the vehicle front cover model into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and a front cover main body 3 to be spatially transformed.

[0134] The calculation module 320 is used to calculate the first position coordinates of the first hard point and the second position coordinates of the second hard point in the rod part based on the geometric relationship of the four-bar hinge of the vehicle front hood model and according to the first rotation angle of the first link in the four-bar hinge.

[0135] The transformation module 330 is used to transform the front cover body part 3 to an open position or a closed position corresponding to the first rotation angle based on the first position coordinates and the second position coordinates through a three-point aligned geometric transformation method.

[0136] The control module 340 is used to automatically determine the limit position of the vehicle front cover model by iteratively adjusting the first rotation angle and detecting whether the rod part interferes, until the iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, and the first rotation angle corresponding to the stop iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

[0137] In the above optional methods, the calculation module 320 is specifically used for:

[0138] Based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point, calculate the first position coordinates of the first hard point;

[0139] Based on the first position coordinates and the first rod length between the first hard point and the second hard point, construct the first circle equation;

[0140] Based on the coordinates of the second fixed point in the four-bar linkage and the length of the second link between the second fixed point and the second hard point, a second circle equation is constructed.

[0141] By simultaneously solving the equations of the first and second circles, the coordinates of the two candidate positions of the second hard point can be obtained.

[0142] The second position coordinate of the second hard point is determined from the two candidate position coordinates based on the angle between the initial position vector of the second hard point and the vectors corresponding to the two candidate position coordinates.

[0143] In the above optional embodiments, the transformation module 330 is specifically used for:

[0144] Based on the first rotation angle and the symmetry of the four-bar hinge, the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link section are calculated.

[0145] Three non-coplanar target points are selected from the first and second position coordinates located on the left side of the rod portion, and the third and fourth position coordinates located on the right side of the rod portion;

[0146] Select three non-coplanar source points corresponding to the three non-coplanar target points in the initial state of the front cover main body 3;

[0147] The transformation matrix is ​​calculated based on the three non-coplanar source points and the three non-coplanar target points, and the transformation matrix is ​​applied to transform the front cover body part 3 from the initial state to the open or closed position corresponding to the first rotation angle.

[0148] In the above-mentioned optional methods, the control module 340 is specifically used for:

[0149] Set the initial angle and preset increment of the first rotation angle;

[0150] Based on the current first rotation angle, perform position calculation and transformation operation for the front cover opening, and detect whether the rod part interferes after the transformation operation;

[0151] When no interference occurs, the first rotation angle is increased by the preset step size, and the calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0152] When interference occurs, the preset increment step size is reduced according to the dichotomy method, and the first rotation angle is reduced according to the reduced preset increment step size. The calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0153] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit opening angle of the vehicle front cover model.

[0154] In the above-mentioned optional methods, the control module 340 is specifically used for:

[0155] Set the initial angle and preset reduction step size for the first rotation angle;

[0156] Based on the current first rotation angle, perform position calculation and transformation operation for front cover closure, and detect whether interference occurs in the rod part after the transformation operation;

[0157] When no interference occurs, the first rotation angle is reduced according to the preset step size, and the calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0158] When interference occurs, the preset reduction step size is reduced according to the dichotomy method, and the first rotation angle is increased according to the reduced preset reduction step size. The calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0159] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit closing angle of the vehicle front cover model.

[0160] In the above optional methods, the calculation module 320 is specifically used for:

[0161] Based on the geometric relationship of the first hard point rotating around the first fixed point in a preset plane, the first position coordinates of the first hard point are calculated according to the first rotation angle, the coordinates of the first fixed point, and the initial coordinates of the first hard point, wherein the rotation axis is an axis perpendicular to the preset plane and passing through the first fixed point.

[0162] In the above optional embodiments, the transformation module 330 is specifically used for:

[0163] Based on the first rotation angle and the symmetry of the four-bar hinge, the first position coordinates of the first hard point are obtained by mirror transformation to obtain the third position coordinates of the third hard point, and the second position coordinates of the second hard point are obtained by mirror transformation to obtain the fourth position coordinates of the fourth hard point;

[0164] The plane of symmetry for the mirror transformation is the longitudinal plane of symmetry of the vehicle front hood model.

[0165] The technical solution of this embodiment can solve the problems of time-consuming modeling of vehicle front cover models, laborious manual adjustment, and insufficient accuracy, and improve the efficiency of front cover simulation opening and closing control and model accuracy.

[0166] It should be noted that the simulation opening and closing control device for the vehicle front hood model provided in the above embodiments and the simulation opening and closing control method for the vehicle front hood model provided in the aforementioned embodiments belong to the same concept. The specific way in which each module and unit performs operations has been described in detail in the method embodiments, and will not be repeated here.

[0167] Figure 7 The diagram shows a structural schematic of an embodiment of the simulation opening and closing control device for a vehicle front hood model provided in this application. It also shows a structural schematic of a computer system suitable for implementing the simulation opening and closing control device for a vehicle front hood model in the embodiments of this application. The specific embodiments of this application do not limit the specific implementation of the simulation opening and closing control device for a vehicle front hood model.

[0168] Please see Figure 7 As shown, the simulation opening and closing control device for the vehicle front hood model includes: a controller; and a memory for storing one or more programs, which, when executed by the controller, perform the aforementioned simulation opening and closing control method for the vehicle front hood model.

[0169] Please continue reading. Figure 7As shown, the computer system 500 of the simulation opening and closing control device for the vehicle hood model includes a Central Processing Unit (CPU) 501, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 502 or programs loaded from storage section 508 into Random Access Memory (RAM) 503, such as executing the methods described in the above embodiments. The RAM 503 also stores various programs and data required for system operation. The CPU 501, ROM 502, and RAM 503 are interconnected via a bus 504. An input / output (I / O) interface 505 is also connected to the bus 504.

[0170] The following components are connected to I / O interface 505: an input section 506 including a keyboard, mouse, etc.; an output section 507 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 508 including a hard disk, etc.; and a communication section 509 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 509 performs communication processing via a network such as the Internet. A drive 510 is also connected to I / O interface 505 as needed. Removable media 511, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., are installed on drive 510 as needed so that computer programs read from them can be installed into storage section 508 as needed.

[0171] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 509, and / or installed from removable medium 511. When the computer program is executed by central processing unit (CPU) 501, it performs various functions defined in the system of this application.

[0172] Another aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the simulation opening and closing control method for a vehicle hood model as described above. This computer-readable storage medium may be included in the simulation opening and closing control device for the vehicle hood model described in the above embodiments, or it may exist independently and not be assembled into the electronic device.

[0173] Another aspect of this application provides a computer program product or computer program that includes at least one executable instruction that, when executed on a simulation opening and closing control device / equipment for a vehicle hood model, causes the simulation opening and closing control device / equipment for the vehicle hood model to perform the simulation opening and closing control method for the vehicle hood model as described above.

[0174] Specifically, the executable instructions can be used to cause the simulation opening and closing control device / device of the vehicle front hood model to perform the following operations:

[0175] The vehicle front cover model is divided into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and a front cover main body part that needs to be spatially transformed.

[0176] Based on the geometric relationship of the four-bar hinge of the vehicle front hood model, and according to the first rotation angle of the first link in the four-bar hinge, the first position coordinates of the first hard point and the second position coordinates of the second hard point in the link part are calculated.

[0177] Based on the first position coordinates and the second position coordinates, the front cover body part 3 is transformed to the open or closed position corresponding to the first rotation angle through a three-point aligned geometric transformation method.

[0178] By iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod part, the limit position of the vehicle front cover model is automatically determined. The iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs. The first rotation angle corresponding to the stop of iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

[0179] In an alternative approach, the step of calculating the first position coordinates of the first hard point and the second position coordinates of the second hard point in the link section based on the geometric relationship of the four-bar hinge of the vehicle hood model and according to the first rotation angle of the first link in the four-bar hinge, further includes:

[0180] Based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point, calculate the first position coordinates of the first hard point;

[0181] Based on the first position coordinates and the first rod length between the first hard point and the second hard point, construct the first circle equation;

[0182] Based on the coordinates of the second fixed point in the four-bar linkage and the length of the second link between the second fixed point and the second hard point, a second circle equation is constructed.

[0183] By simultaneously solving the equations of the first and second circles, the coordinates of the two candidate positions of the second hard point can be obtained.

[0184] The second position coordinate of the second hard point is determined from the two candidate position coordinates based on the angle between the initial position vector of the second hard point and the vectors corresponding to the two candidate position coordinates.

[0185] In an alternative approach, the step of transforming the front cover body portion 3 to an open or closed position corresponding to the first rotation angle using a three-point aligned geometric transformation method based on the first and second position coordinates further includes:

[0186] Based on the first rotation angle and the symmetry of the four-bar hinge, the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link section are calculated.

[0187] Three non-coplanar target points are selected from the first and second position coordinates located on the left side of the rod portion, and the third and fourth position coordinates located on the right side of the rod portion;

[0188] Select three non-coplanar source points corresponding to the three non-coplanar target points in the initial state of the front cover main body 3;

[0189] The transformation matrix is ​​calculated based on the three non-coplanar source points and the three non-coplanar target points, and the transformation matrix is ​​applied to transform the front cover body part 3 from the initial state to the open or closed position corresponding to the first rotation angle.

[0190] In one alternative approach, the step of automatically determining the limit position of the vehicle front hood model by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the stop iteration as the limit opening angle of the vehicle front hood model, further includes:

[0191] Set the initial angle and preset increment of the first rotation angle;

[0192] Based on the current first rotation angle, perform position calculation and transformation operation for the front cover opening, and detect whether the rod part interferes after the transformation operation;

[0193] When no interference occurs, the first rotation angle is increased by the preset step size, and the calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0194] When interference occurs, the preset increment step size is reduced according to the dichotomy method, and the first rotation angle is reduced according to the reduced preset increment step size. The calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated.

[0195] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit opening angle of the vehicle front cover model.

[0196] In one alternative approach, the step of automatically determining the limiting position of the vehicle front hood model's closure by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the point where iteration stops as the limiting closure angle of the vehicle front hood model, further includes:

[0197] Set the initial angle and preset reduction step size for the first rotation angle;

[0198] Based on the current first rotation angle, perform position calculation and transformation operation for front cover closure, and detect whether interference occurs in the rod part after the transformation operation;

[0199] When no interference occurs, the first rotation angle is reduced according to the preset step size, and the calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0200] When interference occurs, the preset reduction step size is reduced according to the dichotomy method, and the first rotation angle is increased according to the reduced preset reduction step size. The calculation of the front cover closing position, the transformation operation, and the interference detection are repeated.

[0201] When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit closing angle of the vehicle front cover model.

[0202] In an alternative approach, the step of calculating the first position coordinates of the first hard point based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point further includes:

[0203] Based on the geometric relationship of the first hard point rotating around the first fixed point in a preset plane, the first position coordinates of the first hard point are calculated according to the first rotation angle, the coordinates of the first fixed point, and the initial coordinates of the first hard point, wherein the rotation axis is an axis perpendicular to the preset plane and passing through the first fixed point.

[0204] In an alternative approach, the step of calculating the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link portion based on the first rotation angle and the symmetry of the four-bar hinge further includes:

[0205] Based on the first rotation angle and the symmetry of the four-bar hinge, the first position coordinates of the first hard point are obtained by mirror transformation to obtain the third position coordinates of the third hard point, and the second position coordinates of the second hard point are obtained by mirror transformation to obtain the fourth position coordinates of the fourth hard point;

[0206] The plane of symmetry for the mirror transformation is the longitudinal plane of symmetry of the vehicle front hood model.

[0207] The technical solution of this embodiment can solve the problems of time-consuming modeling of vehicle front cover models, laborious manual adjustment, and insufficient accuracy, and improve the efficiency of front cover simulation opening and closing control and model accuracy.

[0208] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. The transmitted data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0209] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0210] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0211] According to one aspect of the embodiments of this application, a computer system is also provided, including a Central Processing Unit (CPU), which can perform various appropriate actions and processes based on a program stored in read-only memory (ROM) or a program loaded from storage into random access memory (RAM), such as performing the methods described above. Various programs and data required for system operation are also stored in the RAM. The CPU, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0212] The following components are connected to the I / O interface: input components including keyboards, mice, etc.; output components including cathode ray tubes (CRTs), liquid crystal displays (LCDs), and speakers; storage components including hard drives; and communication components including network interface cards such as LAN (Local Area Network) cards and modems. The communication components perform communication processing via networks such as the Internet. Drives are also connected to the I / O interface as needed. Removable media, such as disks, optical discs, magneto-optical discs, semiconductor memories, etc., are installed on the drive as needed so that computer programs read from them can be installed into the storage components as required.

[0213] The above description is merely a preferred exemplary embodiment of this application and is not intended to limit the implementation of this application. Those skilled in the art can easily make corresponding modifications or alterations based on the main concept and spirit of this application. Therefore, the scope of protection of this application should be determined by the scope of protection claimed in the claims.

Claims

1. A simulation opening and closing control method for a vehicle front hood model, characterized in that, The method includes: The vehicle front hood model is divided into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and a front hood main body part that is to be spatially transformed. Based on the geometric relationship of the four-bar hinge of the vehicle front hood model, and according to the first rotation angle of the first link in the four-bar hinge, the first position coordinates of the first hard point and the second position coordinates of the second hard point in the link section are calculated; wherein, the first hard point is a feature point located at the end of the first link in the link section, the second hard point is a feature point located at the end of the second link in the link section, the first link is the link in the four-bar hinge that is connected to the fixed point on the side of the vehicle body and serves as the motion input reference, the first rotation angle is the angle value of the first link rotating around the center of the hinge, and the first position coordinates are the spatial coordinate values ​​of the first hard point after the first link rotates by the first rotation angle; Based on the first position coordinates and the second position coordinates, the front cover body is transformed to the open or closed position corresponding to the first rotation angle using a three-point aligned geometric transformation method. By iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod part, the limit position of the vehicle front cover model is automatically determined. The iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs. The first rotation angle corresponding to the stop of iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

2. The method according to claim 1, characterized in that, The step of calculating the first position coordinates of the first hard point and the second position coordinates of the second hard point in the link section based on the geometric relationship of the four-bar hinge based on the first rotation angle of the first link in the four-bar hinge further includes: Based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point, the first position coordinates of the first hard point are calculated; wherein, the first fixed point is the rotation center of the first link in the four-bar linkage, and the initial coordinates of the first hard point are the coordinate values ​​of the first hard point in the closed state of the vehicle front cover model. Based on the first position coordinates and the first rod length between the first hard point and the second hard point, construct the first circle equation; Based on the coordinates of the second fixed point in the four-bar linkage and the length of the second link between the second fixed point and the second hard point, a second circle equation is constructed; wherein, the second fixed point is the rotation center of the second link in the four-bar linkage. By simultaneously solving the equations of the first and second circles, the coordinates of the two candidate positions of the second hard point can be obtained. Based on the angle between the initial position vector of the second hard point and the vectors corresponding to the two candidate position coordinates, the second position coordinate of the second hard point is determined from the two candidate position coordinates; wherein, the initial position vector of the second hard point is: a spatial vector pointing from the second fixed point to the initial position of the second hard point.

3. The method according to claim 2, characterized in that, The step of transforming the front cover body to an open or closed position corresponding to the first rotation angle using a three-point aligned geometric transformation method based on the first and second position coordinates further includes: Based on the first position coordinates of the first hard point and the second position coordinates of the second hard point located on the left side of the rod section calculated from the first rotation angle, and the symmetry of the four-bar hinge, the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the rod section are calculated through mirror transformation; wherein, the third hard point is a feature point at the end of the first link of the right hinge in the rod section, the fourth hard point is a feature point at the end of the second link of the right hinge in the rod section, the third position coordinates are the spatial coordinates of the third hard point after the right hinge moves, and the fourth position coordinates are the spatial coordinates of the fourth hard point after the right hinge moves; Three non-coplanar target points are selected from the first and second position coordinates located on the left side of the rod portion, and the third and fourth position coordinates located on the right side of the rod portion; Select three non-coplanar source points corresponding to the three non-coplanar target points in the initial state of the main body of the front cover; wherein, the initial state is the original state of the vehicle front cover model in the closed position; the three non-coplanar source points are: three non-coplanar points selected in the initial state that correspond to the three non-coplanar target points; Based on the coordinates of the three non-coplanar source points and the coordinates of the three non-coplanar target points, a transformation matrix is ​​calculated using the three-point alignment geometric transformation method. The transformation matrix is ​​then applied to transform all nodes of the front cover body from their initial state to the open or closed position corresponding to the first rotation angle.

4. The method according to any one of claims 1 to 3, characterized in that, The step of automatically determining the limit position of the vehicle front hood model by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod part, until the iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, and determining the first rotation angle corresponding to the stop iteration as the limit opening angle of the vehicle front hood model, further includes: Set the initial angle and preset increment of the first rotation angle; Based on the current first rotation angle, perform position calculation and transformation operation for the front cover opening, and detect whether the rod part interferes after the transformation operation; When no interference occurs, the first rotation angle is increased by the preset step size, and the calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated. When interference occurs, the preset increment step size is reduced according to the dichotomy method, and the first rotation angle is reduced according to the reduced preset increment step size. The calculation of the opening position of the front cover, the transformation operation, and the interference detection are repeated. When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit opening angle of the vehicle front cover model.

5. The method according to any one of claims 1 to 3, characterized in that, The step of automatically determining the limit position of the vehicle front hood model's closure by iteratively adjusting the first rotation angle and detecting whether interference occurs in the rod portion, until the iteration stops when the adjustment amount of the first rotation angle is less than a set tolerance and no interference occurs, and determining the first rotation angle corresponding to the point where iteration stops as the limit closure angle of the vehicle front hood model, further includes: Set the initial angle and preset reduction step size for the first rotation angle; Based on the current first rotation angle, perform position calculation and transformation operation for the front cover closing, and detect whether interference occurs in the rod part after the transformation operation; When no interference occurs, the first rotation angle is reduced according to the preset step size, and the calculation of the front cover closing position, the transformation operation, and the interference detection are repeated. When interference occurs, the preset reduction step size is reduced according to the dichotomy method, and the first rotation angle is increased according to the reduced preset reduction step size. The calculation of the front cover closing position, the transformation operation, and the interference detection are repeated. When the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, the iteration stops, and the first rotation angle corresponding to the stop of iteration is determined as the limit closing angle of the vehicle front cover model.

6. The method according to claim 2, characterized in that, The step of calculating the first position coordinates of the first hard point based on the first rotation angle, the coordinates of the first fixed point in the four-bar linkage, and the initial coordinates of the first hard point further includes: Based on the geometric relationship of the first hard point rotating around the first fixed point in a preset plane, the first position coordinates of the first hard point are calculated according to the first rotation angle, the coordinates of the first fixed point, and the initial coordinates of the first hard point, wherein the rotation axis is an axis perpendicular to the preset plane and passing through the first fixed point.

7. The method according to claim 3, characterized in that, The step of calculating the third position coordinates of the third hard point and the fourth position coordinates of the fourth hard point located on the right side of the link portion based on the first rotation angle and the symmetry of the four-bar hinge further includes: Based on the first rotation angle and the symmetry of the four-bar hinge, the first position coordinates of the first hard point are obtained by mirror transformation to obtain the third position coordinates of the third hard point, and the second position coordinates of the second hard point are obtained by mirror transformation to obtain the fourth position coordinates of the fourth hard point; The plane of symmetry for the mirror transformation is the longitudinal plane of symmetry of the vehicle front hood model.

8. A simulation opening and closing control device for a vehicle front hood model, characterized in that, The device includes: The partitioning module is used to divide the vehicle front cover model into a fixed part connected to the vehicle body, a rod part that rotates around the hinge center, and a front cover main body part that needs to be spatially transformed. The calculation module is used to calculate the first position coordinates of the first hard point and the second position coordinates of the second hard point in the rod part based on the geometric relationship of the four-bar hinge of the vehicle front hood model and according to the first rotation angle of the first link in the four-bar hinge; wherein, the first hard point is a feature point located at the end of the first link in the rod part, the second hard point is a feature point located at the end of the second link in the rod part, the first link is the link in the four-bar hinge that is connected to the fixed point on the side of the vehicle body and serves as the motion input reference, the first rotation angle is the angle value of the first link rotating around the center of the hinge, and the first position coordinates are the spatial coordinate values ​​of the first hard point after the first link rotates by the first rotation angle; The transformation module is used to transform the front cover body part to an open or closed position corresponding to the first rotation angle based on the first position coordinates and the second position coordinates using a three-point aligned geometric transformation method. The control module is used to automatically determine the limit position of the vehicle front cover model by iteratively adjusting the first rotation angle and detecting whether the rod part interferes, until the iteration stops when the adjustment amount of the first rotation angle is less than the set tolerance and no interference occurs, and the first rotation angle corresponding to the stop iteration is determined as the limit opening angle or limit closing angle of the vehicle front cover model.

9. A simulation opening and closing control device for a vehicle front hood model, characterized in that, include: Controller; A memory for storing one or more programs, which, when executed by a controller, cause the controller to implement the simulation opening and closing control method for the vehicle front hood model as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which includes at least one executable instruction. When the executable instruction is executed on the simulation opening and closing control device / equipment of the vehicle front hood model, it causes the simulation opening and closing control device / equipment of the vehicle front hood model to perform the operation of the simulation opening and closing control method of the vehicle front hood model as described in any one of claims 1 to 7.

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