Virtual assembly detection method, virtual assembly detection device, assembly system and medium

Abstract

The application provides a virtual assembly detection method, a virtual assembly detection device, an assembly system and a medium, wherein the virtual assembly detection method comprises the following steps: S100: acquiring an orientation reference point of a first part, an orientation reference point and a monitoring point of a second part, and an assembly mode of the first part and the second part; S200: based on the acquired orientation reference points of the first part and the second part, performing virtual assembly to obtain virtual coordinate data of the monitoring point after virtual assembly; S300: based on the virtual coordinate data, judging whether the assembly quality of the first part is qualified; wherein step S200 comprises the following sub-steps: S210: acquiring coordinate data of the orientation reference points of the first part and the second part, and calculating a translation vector T and a rotation matrix R when the second part is matched to the first part in the assembly mode based on the coordinate data; S220: calculating virtual coordinate data of the monitoring point according to the calculated translation vector T and rotation matrix R.

Description

TECHNICAL FIELD

[0001] The present application relates to a virtual assembly detection method, a virtual assembly detection device, an assembly system and a computer readable storage medium for performing such a method. BACKGROUND

[0002] In the assembly process of parts, for example, during the assembly of a complete vehicle, the assembly quality of parts needs to be monitored. Advantageously, the assembly quality of parts is monitored in real time and the assembly process is stopped and adjusted in time in the case of substandard assembly quality.

[0003] It is known from the prior art that an assembly detection method measures local references, for example, the measurement of assembly joints, by means of special measurement software and directly displays the measurement results, which cannot realize completely offline automatic detection. Furthermore, the measurement system can give an inference about whether the completed assembly process meets the assembly requirements, but cannot give an inference about whether the subsequent assembly process of the part is qualified on this basis. SUMMARY

[0004] According to different aspects, the purpose of the present application is to provide a virtual assembly detection method, a virtual assembly detection device, an assembly system and a computer readable storage medium, which can prospectively and more accurately detect the assembly quality of a target part (i.e. a detection object, hereinafter also referred to as a first part), wherein the target part can have manufacturing deviations and / or existing assembly deviations.

[0005] In addition, the present application also aims to solve or alleviate other technical problems existing in the prior art.

[0006] According to a first aspect of the present application, the above problems are solved by providing a virtual assembly detection method, specifically comprising the following steps:

[0007] S100: obtaining an orientation reference point of a first part, an orientation reference point and a monitoring point of a second part, and an assembly mode of the first part and the second part, wherein the second part has a theoretical state of the first part or the second part is a counterpart for assembly at the first part;

[0008] S200: based on the obtained orientation reference points of the first part and the second part, performing virtual assembly to obtain virtual coordinate data of the monitoring point after virtual assembly;

[0009] S300: judging whether the assembly quality of the first part is qualified based on the virtual coordinate data;

[0010] Wherein, step S200 comprises the following sub-steps:

[0011] S210: obtaining coordinate data of directional reference points of the first part and the second part, and calculating a translation vector T and a rotation matrix R when the second part is matched to the first part in the assembly manner based on the coordinate data;

[0012] S220: calculating virtual coordinate data of the monitoring points according to the calculated translation vector T and the rotation matrix R.

[0013] In the virtual assembly detection method according to the first aspect of the present application, the assembly manner is a 3-2-1 assembly manner, or the assembly manner is an N-2-1 assembly manner, where N is an integer greater than 3, and the sub-step S210 comprises the following sub-steps:

[0014] S211: obtaining coordinate data of directional reference points of the first part, and determining a coordinate system A defined by the coordinate data;

[0015] S212: obtaining coordinate data of directional reference points of the second part, and determining a coordinate system B defined by the coordinate data;

[0016] S213: calculating a translation vector T and a rotation matrix R when the coordinate system B is matched to the coordinate system A.

[0017] In the virtual assembly detection method according to the first aspect of the present application, in the sub-step S213, based on the origin coordinate matrix O a and the coordinate axis vector matrix R a of the coordinate system A, and the origin coordinate matrix O b and the coordinate axis vector matrix R b of the coordinate system B, the translation vector T and the rotation matrix R are calculated according to the following formula:

[0018]

[0019] where R a ′ is the transpose matrix of the coordinate axis vector matrix R a ; R' is the transpose matrix of the rotation matrix R.

[0020] In the virtual assembly detection method according to the first aspect of the present application, the assembly manner is a six-directional positioning assembly manner, and the sub-step S210 comprises the following sub-steps:

[0021] S211': obtaining coordinate matrices P a and P b of six directional reference points of the first part and the second part, respectively;

[0022] S212':obtaining a normal matrix D of the six normal vectors;

[0023] S213':based on the coordinate matrix P a , P b and the normal matrix D, calculating the translation vector T and the rotation matrix R.

[0024] In the virtual assembly detection method according to the first aspect of the present application, in sub-step S213', a solving equation is constructed and based on which the translation vector T and the rotation matrix R are solved, wherein the solving equation is expressed as: the sum of each row element of the Hadamard product of the matrix ((P b R+T)-P a ) and the normal matrix D is zero.

[0025] In the virtual assembly detection method according to the first aspect of the present application, step S300 comprises the following sub-steps:

[0026] S310: obtaining the deviation of the virtual coordinate data of the monitoring point from the pre-stored reference coordinate data;

[0027] S320: in response to the deviation being less than a preset deviation threshold, determining that the assembly quality of the first part is qualified.

[0028] According to the second aspect of the present application, a virtual assembly detection device for executing the above method is further proposed, which comprises:

[0029] an obtaining module configured to obtain the directional reference point of the first part, the directional reference point and the monitoring point of the second part, and the assembly mode of the first part and the second part;

[0030] a virtual assembly module configured to perform virtual assembly based on the obtained directional reference points of the first part and the second part, so as to obtain the virtual coordinate data of the monitoring point after virtual assembly;

[0031] a judgment module configured to judge whether the assembly quality of the first part is qualified based on the virtual coordinate data;

[0032] wherein the virtual assembly module comprises a solving submodule and a generating submodule, the solving submodule is configured to obtain the coordinate data of the directional reference points of the first part and the second part, and calculate the translation vector T and the rotation matrix R when the second part is matched to the first part in the assembly mode based on the coordinate data; and the generating submodule is configured to calculate the virtual coordinate data of the monitoring point according to the calculated translation vector T and the rotation matrix R.

[0033] In the virtual assembly detection device according to the second aspect of the present application, the virtual assembly detection device further comprises a database or is in communication connection with a database, and the first digital model of the first part and the second digital model of the second part are stored in the database, so as to be acquired by the acquisition module.

[0034] According to the third aspect of the present application, a kind of assembly system is further proposed, it includes installation tool for executing assembly operation and the virtual assembly detection device described above.

[0035] Finally, according to the fourth aspect of the present application, a kind of computer readable storage medium is further proposed, and computer program is stored on it, wherein the computer program is executed by processor to realize the virtual assembly method described above.

[0036] By installing and matching detection object "first part" in virtual environment and evaluating the quality of detection object at this time node based on this, the virtual assembly detection method can realize targeted and forward-looking assembly quality detection. BRIEF DESCRIPTION OF DRAWINGS

[0037] The above and other features of the present application will become apparent from the following description of the application, taken in conjunction with the accompanying drawings, wherein,

[0038] Figure 1 The main steps of the virtual assembly method according to the present application are shown;

[0039] Figure 2 The flow chart of one embodiment of the virtual assembly method is shown;

[0040] Figure 3 The structural block diagram of the virtual assembly device according to the present application is shown. DETAILED DESCRIPTION

[0041] It is easy to understand that, according to the technical solution of the present application, a person skilled in the art can propose a plurality of structure modes and implementation modes which can be replaced with each other without changing the essential spirit of the present application. Therefore, the following specific embodiments and drawings are only exemplary description of the technical solution of the present application, and should not be regarded as the whole or regarded as the limitation or restriction of the technical solution of the present application.

[0042] The orientation terms mentioned or possibly mentioned in the present specification, such as up, down, left, right, front, back, front side, back side, top, bottom, etc., are defined with respect to the configuration shown in the respective drawing, and are relative concepts, and thus can change accordingly depending on different positions, different use states, etc. Therefore, these or other orientation terms should not be interpreted as restrictive terms. In addition, the terms "first", "second", "third", etc. or similar expressions are only used for description and differentiation purposes, and cannot be understood as indicating or implying the relative importance of the corresponding components.

[0043] It is realized that firstly, manufacturing deviations from the theoretical design can occur during the manufacturing process of the components, and it is necessary to detect in advance whether the manufacturing deviations meet the requirements of the subsequent assembly quality. Furthermore, although the previous assembly quality of the assembled components can be evaluated by measuring the assembly parameters (such as assembly seams) between the two counterpart components or by measuring the assembly parameters of the assembled components relative to the preset reference. However, the components that have completed part of the assembly work can no longer be well matched with the subsequent counterpart due to the influence of the assembly dimension chain tolerance, and it is also necessary to know in advance in order to adjust the previous assembly work in time.

[0044] The virtual assembly detection method according to the present application comprises the following steps as shown in Figure 1 and Figure 2

[0045] S100: acquiring an orientation reference point of a first component, an orientation reference point and a monitoring point of a second component, and an assembly manner of the first component and the second component, wherein the second component has a theoretical state of the first component or the second component is a counterpart for assembly at the first component;

[0046] S200: performing virtual assembly based on the acquired orientation reference points of the first component and the second component, to obtain virtual coordinate data of the monitoring point after virtual assembly;

[0047] S300: judging whether the assembly quality of the first component is qualified based on the virtual coordinate data;

[0048] Wherein, step S200 comprises the following sub-steps:

[0049] S210: acquiring coordinate data of the orientation reference points of the first component and the second component, and calculating a translation vector T and a rotation matrix R when the second component is matched to the first component in the assembly manner based on the coordinate data;

[0050] S220: calculating the virtual coordinate data of the monitoring point according to the calculated translation vector T and rotation matrix R. ​

[0051] It should be noted that the step names mentioned above (and below) are only used for distinguishing between steps and facilitating the reference of steps, and do not represent the sequential relationship between steps, and the flowchart of the accompanying drawings is also only an example of performing the method. Without obvious conflicts, the steps can be performed in various sequences or simultaneously.

[0052] The virtual assembly detection method can be performed by a virtual assembly detection device 100 according to the second aspect of the present application, which comprises the following modules as shown in the figure: Figure 3

[0053] The acquisition module 110 is configured to acquire the directional reference point of the first part, the directional reference point and the monitoring point of the second part, and the assembly mode of the first part and the second part.

[0054] The virtual assembly module 120 is configured to perform virtual assembly based on the acquired directional reference points of the first part and the second part, to obtain the virtual coordinate data of the monitoring point after virtual assembly.

[0055] The judgment module 130 is configured to judge whether the assembly quality of the first part is qualified based on the virtual coordinate data.

[0056] The virtual assembly module 120 comprises a solving submodule 121 and a generating submodule 122. The solving submodule is configured to acquire the coordinate data of the directional reference points of the first part and the second part, and calculate the translation vector T and the rotation matrix R when the second part is matched to the first part in the assembly mode based on the coordinate data. The generating submodule 122 is configured to calculate the virtual coordinate data of the monitoring point according to the calculated translation vector T and rotation matrix R.

[0057] Here, the first part as the detection object is a manufactured part and may have manufacturing deviation, or the first part is a partially assembled part and may have manufacturing deviation and assembly deviation at this time. The detection of assembly quality proposed here refers to the pre-detection of whether the detection object meets the requirements of the subsequent assembly process.

[0058] ​The following gives several different examples of the second part with respect to the first part with associated deviations. One of them, the second part can be the counterpart in the theoretical state, which needs to be subsequently assembled to the detection object "first part", for example, the first part is a car body, and the second part is a theoretical front headlamp. The second, the second part can be in the actual state (that is, it can have manufacturing deviations), which needs to be subsequently assembled to the detection object "first part" counterpart, for example, the first part is a car body, and the second part is an actual front headlamp. The third, the second part can be the first part in the theoretical state, for example, the detection object "first part" is an actual car body, and the second part is a car body in the theoretical state without deviation.

[0059] By installing and matching the second part with the first part in the actual state in the virtual environment and evaluating the current quality of the first part based on this, the assembly quality detection realized in this way can take into account both the manufacturing deviations of the first part itself and the effects of the assembly deviations of the previously assembled parts on the subsequent assembly operation. Thus, targeted and forward-looking assembly quality detection can be achieved.

[0060] In step S100, the directional reference point refers to a point that can define the assembly relationship, and the directional reference points of the first part and the second part correspond to each other; and the monitoring point relates to the point for judging the assembly quality. Among them, the directional reference point of the first part (i.e. the detection object) can not only reflect its own structure, but also reflect its assembly relationship with other counterparts that have been assembled with it in the case of being an intermediate part. Taking the detection object first part as "car body" and the second part as the counterpart "theoretical front headlamp" to be assembled thereon as an example, the directional reference point of the first part can be the center point of the assembly hole (such as the center point of the rivet hole) on the car body for the front headlamp, and the directional reference point of the second part can be the center point of the assembly hole on the theoretical front headlamp corresponding to the assembly hole; the monitoring point can be located on the edge of the front headlamp matched with the car body (for example, uniformly selected along the edge of the front headlamp) or can also be a key point affecting the safety or aesthetics of the car.

[0061] It should be noted that in step S100, the relevant orientation reference points for subsequent virtual assembly and monitoring points for observation are required to be acquired, without the need to acquire the structure or overall dimensions of the entire part. In the virtual assembly detection method or device according to the present application, the relevant description of the first part and the second part can extend to the above-mentioned orientation reference points or monitoring points. The virtual assembly detection method is applicable to the mounting process of various parts, and is not limited to the vehicle assembly process described above. In this article, the vehicle assembly process is only used as an example for clarity, and the first part to be detected, the "vehicle body", and the second part, the "theoretical front headlamp", are used as examples for detailed description below for the sake of simplicity.

[0062] In this step S100, the position information of the above-mentioned orientation reference points and monitoring points can be directly called, or can also be acquired relying on a digital model for intuitive display to the detection personnel. Corresponding to the latter case, the virtual assembly detection device 100 according to the present application can also optionally have (not shown) a database or be communicatively connected thereto, wherein the first digital model of the first part and the second digital model of the second part are stored in the database for the acquisition module to collect or acquire the position information of the relevant points. For example, the real digital model of the vehicle body and the theoretical digital model of the theoretical front headlamp are stored in the database.

[0063] Exemplarily, the vehicle body as the detection object (i.e. the first part) can be a white vehicle body without assembled parts or can be assembled with other parts according to the assembly process itself, wherein the prior assembly to a certain extent will cause a certain torsion or translation of the vehicle body, especially the part for mounting the front headlamp, which will also cause the deviation of the orientation reference points for assembly with respect to the theoretical design. In the vehicle assembly process, the position data of the relevant orientation reference points for assembly are directly acquired in step S100 for the subsequent virtual assembly process, wherein the number of the orientation reference points is selected as needed.

[0064] Exemplarily, for the acquisition of the orientation reference points and monitoring points relying on the digital model, for example, the vehicle parts can be scanned by means of a scanner to form scanned point cloud data of the parts and to be assembled into a three-dimensional digital model. In the assembly quality detection, the entire vehicle assembly digital model can be called as the real digital model of the vehicle body to be detected, or the digital model of the vehicle body for mounting the front headlamp in the vehicle assembly digital model can also be selected as the above-mentioned real digital model. For example, the vehicle assembly digital model is constructed in the initial coordinate system, which covers or represents the orientation reference points defining the assembly relationship and the monitoring points for assembly quality evaluation, which carry the position information in the initial coordinate system by themselves.

[0065] In one possible embodiment, a real model of the first part in the initial coordinate system is acquired, on which the assembly holes for the second part, or the orientation reference points and possibly the monitoring points are marked for subsequent selection. For example, the assembly holes and the monitoring points can be distinguished by different colors. In addition, a second model of the second part in the initial coordinate system is acquired, and on which the orientation reference points and possibly the monitoring points for assembly in the first part are also marked, which can be distinguished by different colors, for example. The first model and the second model can be called from a database of the virtual assembly detection device according to the application, if present. It should be noted here that in the case where the second part represents the real state of the first part, the orientation reference points of the two are the same and only differ in the positional data or the coordinate data in the initial coordinate system.

[0066] The virtual assembly quality detection method according to the application is mainly based on the following idea: whether the detection object itself or the previous assembly process is qualified is judged by observing the influence on the monitoring points of the second part caused by assembling the orientation reference points (or also said, the second model) of the second part to the orientation reference points (or also said, the first model) of the first part. If it is identified that the detection object first part cannot meet the requirements of the subsequent assembly process, the first part should be adjusted in time.

[0067] Taking the first part as a real car body and the second part as a theoretical headlamp as an example, in sub-step S210, the coordinate data of the orientation reference points of the real car body in the initial coordinate system and the coordinate data of the orientation reference points of the theoretical headlamp in the initial coordinate system are acquired. Each coordinate data can be represented in the form of (x, y, z), and optionally, a plurality of coordinate data of the real car body and the theoretical headlamp can be represented in the form of a matrix, respectively. Then, the translation and rotation of the orientation reference points of the theoretical headlamp to match the orientation reference points of the actual car body are calculated. It should be understood by those skilled in the art that in this process, the real car body and the theoretical headlamp can be regarded as rigid bodies, and the motion of each point on the rigid body is the same. That is, the translation vector T and the rotation matrix R obtained for the orientation reference points of the theoretical headlamp are also applicable to the monitoring points thereof.

[0068] In sub-step S220, first, the initial coordinate data of at least one selected monitoring point of the theoretical headlamp in the initial coordinate system is acquired and represented as an initial coordinate matrix P, and then the coordinate matrix P' of the monitoring point after virtual assembly is P' = PR + T.

[0069] In an alternative embodiment, the virtual assembly detection method according to the present application is applicable to different assembly methods and provides specific assembly detection methods for each of them. For example, the 3-2-1 assembly method, the N-2-1 assembly method and the six-way positioning assembly method, which will be described in detail below.

[0070] Firstly, with respect to the 3-2-1 assembly method, that is, the theoretical headlamp (i.e. the second part) is installed on the vehicle body (i.e. the first part) in the 3-2-1 assembly method. Sub-step S310 comprises the following steps:

[0071] S211: obtaining coordinate data of the directional reference points of the first part and determining a coordinate system A defined by the coordinate data;

[0072] S212: obtaining coordinate data of the directional reference points of the second part and determining a coordinate system B defined by the coordinate data;

[0073] S213: calculating the translation vector T and the rotation matrix R when matching the coordinate system B to the coordinate system A.

[0074] Here, the coordinate system A and the coordinate system B can be represented by their origin coordinates and coordinate axis vectors. Specifically, in steps S211 and S212, the coordinate data of the six directional reference points of the first part "real vehicle body" in the initial coordinate system and the coordinate data of the six directional reference points of the theoretical headlamp corresponding thereto in the initial coordinate system are obtained, respectively. The six directional reference points of the real vehicle body are A1, A2, A3 (as the first type of directional reference points); A4, A5 (as the second type of directional reference points) and A6 (the third type of directional reference points), which define a unitized plane respectively and together define the coordinate system A. Correspondingly, the six directional reference points of the theoretical headlamp are B1, B2, B3 (as the first type of directional reference points); B4, B5 (as the second type of directional reference points) and B6 (the third type of directional reference points), which also define a unitized plane respectively and together define the coordinate system B.

[0075] Next, the solution of the coordinate system A defined by the six directional reference points of the real vehicle body will be described as an example:

[0076] Firstly, the plane space vector n1 = (i1, j1, k1) of the unitized plane A defined by the first type of directional reference points A1 (x1, y1, z1), A2 (x2, y2, z2), A3 (x3, y3, z3) is obtained by formula (1): 123

[0077] ​

[0078] Next, project A4(x4,y4,z4), A5(x5,y5,z5), and A6(x6,y6,z6) onto the plane A defined by the first type of orientation reference points. 123 On the plane, we get the projection points A4'(x4',y4',z4'), A5'(x5',y5',z5'), and A6'(x6',y6',z6'). Calculate the equation (2) through the points A4'(x4',y4',z4'), A5'(x5',y5',z5') and perpendicular to plane A. 123 Unit plane A 45 The plane space vector n2=(i2,j2,k2):

[0079]

[0080] Then, the equation (3) is used to calculate the value of the point A6' (x6', y6', z6') perpendicular to the normalized plane A. 123 and A 45 The plane space vector n3=(i3,j3,k3) of plane A6:

[0081]

[0082] Finally, the coordinate system A determined by these six directional reference points is obtained, and the origin coordinate matrix O of the coordinate system A can be obtained. a and the coordinate axis vector matrix R a Here,

[0083]

[0084] Among them, the coordinate axis vector matrix R of coordinate system A a It also reflects the rotation of the vehicle body relative to the initial coordinate system.

[0085] For the theoretical headlight matched to the real car body, six orientation reference points are also selected: B1, B2, B3 (as the first type of orientation reference points); B4, B5 (as the second type of orientation reference points); and B6 (as the third type of orientation reference point). These three types of orientation reference points each define a unit plane and together define the coordinate system B. Next, the coordinate system B determined by the six orientation reference points of the theoretical headlight is calculated using the same method as the coordinate system A, that is, the origin coordinate matrix O of the coordinate system B. b and the coordinate axis vector matrix R b .

[0086] Therefore, in step S213, the translation vector T and rotation matrix R when the theoretical headlight is assembled on the test object body in a 3-2-1 assembly manner can be obtained:

[0087]

[0088] wherein R a is a coordinate axis vector matrix of the coordinate system A; R' is a transpose matrix of the rotation matrix R. a is a transpose matrix of the rotation matrix R.

[0089] For the 3-2-1 assembly mode, in the above formula, the rotation matrix R is a 3x3 matrix, and the translation vector T can be expressed as a 1x3 matrix. Subsequently, the virtual coordinate data of the monitoring points after the virtual assembly is obtained according to the formula P' = PR + T. For example, for a monitoring point, the point matrix P can be expressed as a 1x3 matrix, and the row elements are the coordinate data x, y, z of the monitoring point in the initial coordinate system. If n monitoring points are selected, the point matrix P can be expressed as an n x 3 matrix, wherein each row element is the coordinate data x, y, z of each monitoring point in the initial coordinate system. In this case, T in the formula P' = PR + T is expanded, i.e. the 1x3 matrix T is expanded to an n x 3 matrix, each row of which has the same elements. It should be noted that those skilled in the art should know or know that the expression of the formula can be modified according to the number of monitoring points or the matrix expression, such as selecting left or right multiplication matrix or expanding or transforming the parameters to be substituted, without changing the meaning expressed by the above formula. It should be noted that the virtual assembly of the orientation reference point of the first part and the orientation of the second part from the reference point can refer to the description of the real vehicle body and the theoretical headlamp, which is understandable to those skilled in the art based on the above description.

[0090] Based on this, in step S220, the coordinate data of the monitoring points of the second part in the initial coordinate system after the virtual assembly can be obtained as the virtual coordinate data thereof. In the subsequent step S300, the deviation between the virtual coordinate data and the pre-stored reference coordinate data is obtained (i.e. sub-step S310), and then the calculated deviation is compared with the preset deviation threshold value, if it is less than the deviation threshold value, it is determined that the assembly quality of the measured part is qualified, otherwise it is determined that the assembly quality of the measured part is unqualified (i.e. sub-step S320). Here, corresponding solutions for the reference coordinate data are given for different definitions of the second part. In the case that the second part is a theoretical counterpart or an actual counterpart, the reference coordinate data of the monitoring points is obtained based on the first part and the theoretical counterpart or the actual counterpart in the theoretical state (i.e. without manufacturing deviation and without assembly deviation). Instead, in the case that the second part is the actual first part itself, the reference coordinate data of the monitoring points is obtained based on the actual first part. The reference coordinate data can be directly called and compared with the obtained virtual coordinate data in the virtual assembly detection device according to the present application.

[0091] Next, the N-2-1 assembly mode (where N is an integer greater than 3) is described, that is, the second part is mounted on the first part in the N-2-1 assembly mode. In the N-2-1 assembly mode, (N+2+1) directional reference points on the first part and the second part are selected respectively, where N directional reference points are the first type of directional reference points, 2 directional reference points are the second type of directional reference points, and 1 directional reference point is the third type of directional reference point. In a manner substantially the same as the 3-2-1 assembly mode, coordinate system A determined by the (N+2+1) directional reference points on the first part (e.g., the real vehicle body) and coordinate system B determined by the (N+2+1) directional reference points on the second part (e.g., the theoretical headlamp) are calculated, and the translation vector T and the rotation matrix R when the second part is mounted on the first part in the N-2-1 assembly mode are obtained by using the above formula (4).

[0092] Generally, the N-2-1 assembly mode differs from the 3-2-1 assembly mode in that the plane space vector of the first unitized plane formed based on the N first type of directional reference points is determined. Therefore, the detection of the assembly quality of the detection object in the N-2-1 assembly mode can be correspondingly referred to the detection of the assembly quality of the detection object in the 3-2-1 assembly mode, which will not be described again.

[0093] Finally, the six-normal directional positioning assembly mode suitable for the case where the normals of multiple positioning faces are different is described. In the six-normal directional positioning assembly mode, the first part needs to be in contact with the second part in the normal direction at the corresponding points, for example, the real vehicle body should be in contact with the theoretical headlamp in the normal direction at the corresponding directional reference points. Therefore, unlike the 3-2-1 and N-2-1 assembly modes, step S310 includes the following sub-steps:

[0094] S211': Obtain the coordinate matrix P of the six directional reference points of the first part a and the coordinate matrix P of the six directional reference points of the second part b ;

[0095] S212': Obtain the normal matrix D of the six normal vectors;

[0096] S213': Calculate the translation vector T and the rotation matrix R based on the coordinate matrix P a , P b and the normal matrix D.

[0097] Optionally, in step S213', the solving equation of the translation vector T and the rotation matrix R, that is, the matrix ((P b R+T)-P a) and the normal matrix D, and each row inner product is zero, in other words, the matrix ((P b R+T)-P a ) and the sum of each row element of the Hadamard product of the normal matrix D is zero. Subsequently, the virtual coordinate data of the monitoring points after the virtual assembly is determined based on the obtained translation vector T and rotation matrix R, and based on this, it is judged in step S300 whether the assembly quality of the part under test is qualified.

[0098] For the six normal positioning assembly mode, the above P a , P b may be represented as a 6x3 matrix respectively, wherein 6 represents the number of directional reference points, and each row element is the coordinates x, y, z of each directional reference point in the initial coordinate system. The normal matrix D can be represented as a 6x3 matrix, and each row element corresponds to the i, j, k of the normal vector. It should be noted that those skilled in the art should know or know that the meaning represented by the above solving equation does not change, and the expression form of the formula can be modified accordingly according to the different matrix representation.

[0099] It should also be noted here that the solving of the translation vector T and the rotation matrix R is not limited to the above-mentioned manner, but can also be realized by any other feasible manner in the art.

[0100] As can be understood by those skilled in the art, in the case that the second part represents the true state of the first part, the interaction between the plurality of directional reference points and its overall impact on the subsequent assembly process can be reflected as a whole by means of virtual assembly, which cannot be achieved by separately comparing the positional deviation between the actual directional reference points and the theoretical directional reference points.

[0101] In addition, the present application also relates to an assembly system comprising a mounting tool for performing an assembly operation and a virtual assembly detection device capable of performing the virtual assembly detection method according to one or more embodiments of the present application, wherein the mounting tool can be an electric device such as a mechanical arm, a clamp, etc. For the assembly system according to the present application, reference can be made to the explanation for the virtual assembly detection method or device according to the present application, which will not be described again.

[0102] Finally, the present application also relates to a computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the virtual assembly inspection method according to one or more embodiments of the present application. The computer readable storage medium referred to herein includes any available medium that can be accessed by a general purpose or special purpose computer including, but not limited to, RAM, ROM, EPROM, E2PROM, registers, hard disk, removable disk, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer, or a general purpose or special purpose processor. In relation to the computer readable storage medium according to the present application, reference can be made to the explanation of the virtual assembly inspection method according to the present application, which will not be repeated here.

[0103] It should be understood that all the above preferred embodiments are exemplary but not limiting, and various modifications or variations of the above described specific embodiments made by those skilled in the art under the concept of the present application shall fall within the legal protection scope of the present application.

Claims

1. A virtual assembly detection method, characterized in that: The steps include: S100: Acquire an orientation reference point of a first part, an orientation reference point and a monitoring point of a second part, and an assembly method of the first part and the second part, wherein the second part has a theoretical state of the first part or the second part is a counterpart part for assembly at the first part; S200: performing virtual assembly based on the acquired orientation reference points of the first part and the second part to obtain virtual coordinate data of the monitoring point after the virtual assembly; S300: judging whether the assembly quality of the first part is qualified based on the virtual coordinate data; Wherein, step S200 includes the following sub-steps: S210: Acquire coordinate data of orientation reference points of the first part and the second part, and calculate, based on the coordinate data, a translation vector T and a rotation matrix R when the second part is matched to the first part in the assembly manner; S220: Calculate the virtual coordinate data of the monitoring point according to the calculated translation vector T and rotation matrix R. The orientation reference point is a point that can define an assembly relationship, and the orientation reference point of the first part and the orientation reference point of the second part correspond to each other.

2. The virtual assembly detection method according to claim 1, characterized in that: The assembly method is a 3-2-1 assembly method, or the assembly method is an N-2-1 assembly method, wherein N is an integer greater than 3, and sub-step S210 includes the following sub-steps: S211: Acquire coordinate data of the orientation reference point of the first part, and determine a coordinate system A defined by the coordinate data; S212: Acquire coordinate data of the orientation reference point of the second part, and determine a coordinate system B defined by the coordinate data; S213: Calculate the translation vector T and rotation matrix R when matching the coordinate system B to the coordinate system A.

3. The virtual assembly detection method according to claim 2, characterized in that: In sub-step S213, based on the origin coordinate matrix O of the coordinate system A a and the coordinate axis vector matrix R a And the origin coordinate matrix O of the coordinate system B b and the coordinate axis vector matrix R b , the translation vector T and rotation matrix R are calculated using the following formula: in, is the coordinate axis vector matrix R a The transposed matrix of ; R' is the transposed matrix of the rotation matrix R.

4. The virtual assembly detection method according to claim 1, characterized in that: The assembly method is a six-normal positioning assembly method, and sub-step S210 includes the following sub-steps: S211': Obtain the coordinate matrix P of the six orientation reference points of the first part a and the coordinate matrix P of the six orientation reference points of the second part b ; S212': Obtain the normal matrix D of the six normal vectors; S213': Based on the coordinate matrix P a 、P b And the normal matrix D, calculate the translation vector T and rotation matrix R.

5. The virtual assembly detection method according to claim 4, characterized in that: In sub-step S213', a solution equation is constructed and the translation vector T and the rotation matrix R are solved based on the solution equation, wherein the solution equation is expressed as: Matrix The sum of each row element of the Hadamard product with the normal matrix D is zero.

6. The virtual assembly detection method according to claim 1, characterized in that: Step S300 includes the following sub-steps: S310: Obtaining a deviation between the virtual coordinate data of the monitoring point and pre-stored reference coordinate data; S320: In response to the deviation being smaller than a preset deviation threshold, determining that the assembly quality of the first part is qualified.

7. A virtual assembly detection device, characterized in that: It is used to perform the virtual assembly detection method according to any one of claims 1 to 6, and comprises: an acquisition module configured to acquire an orientation reference point of the first part, an orientation reference point and a monitoring point of the second part, and an assembly method of the first part and the second part; a virtual assembly module configured to perform virtual assembly based on the acquired orientation reference points of the first part and the second part to obtain virtual coordinate data of the monitoring point after the virtual assembly; a judging module configured to judge whether the assembly quality of the first part is qualified based on the virtual coordinate data; The virtual assembly module includes a solution submodule and a generation submodule. The solution submodule is configured to obtain the coordinate data of the orientation reference points of the first part and the second part, and calculate the translation vector T and the rotation matrix R when the second part is matched to the first part in the assembly manner based on the coordinate data; the generation submodule is configured to calculate the virtual coordinate data of the monitoring point according to the calculated translation vector T and rotation matrix R. The orientation reference point is a point that can define an assembly relationship, and the orientation reference point of the first part and the orientation reference point of the second part correspond to each other.

8. The virtual assembly detection device according to claim 7, characterized in that: The virtual assembly detection device also includes a database or the virtual assembly detection device is communicatively connected to the database, in which the first digital model of the first part and the second digital model of the second part are stored for the acquisition module to acquire the orientation reference point and monitoring point.

9. An assembly system, characterized in that: It comprises an installation tool for performing an assembly operation and a virtual assembly detection device according to claim 7 or 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the virtual assembly detection method according to any one of claims 1 to 6 is implemented.

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