Geometric model-based fillet surface identification method, apparatus and device, and medium

Abstract

The invention relates to the technical field of computer graphics, computational geometry and CAE (computer aided engineering) simulation, and discloses a fillet surface identification method, device and equipment based on a geometric model and a medium, the method comprises the following steps: carrying out virtual geometric processing on edges of all surfaces in the geometric model to obtain transition edges on an identification surface; determining the identification surface conforming to the surface fillet features as a transition surface; two connecting surfaces connected with the transition surface are selected, the two connecting surfaces are connected with the two ends of the transition edge respectively, the two connecting surfaces conforming to supporting surface features are determined to be a first supporting surface and a second supporting surface respectively, and the supporting surface features are unique features of the two supporting surfaces in fillet surface transition connection; and determining that a transition surface enabling the first supporting surface and the second supporting surface to be in smooth transition is a fillet surface. According to the fillet surface recognition method, the fillet surface in the geometric model can be quickly recognized only through the information of the edge, the recognition process is greatly accelerated, and the recognition is highly accurate.

Description

Technical Field

[0001] The present invention relates to the fields of computer graphics, computational geometry and CAE simulation technology, and in particular to a fillet surface recognition method, device, equipment and medium based on a geometric model. Background Art

[0002] The identification and removal of filleted surfaces in CAE (Computer Aided Engineering) geometric models is a very frequently used function in the CAE pre-processing process and is one of the important processes in the CAE simulation pre-processing process. By removing the complex fillets of the geometric model, the complexity of the generated mesh can be reduced, the quality of the regional mesh can be improved, and the simulation calculation process can be accelerated. In actual operation, the geometric model imported into the CAE software cannot identify the modeling features due to the loss of the parametric modeling process. How to accurately and quickly identify the filleted surfaces in the geometric model has become one of the important ability evaluation criteria for CAE pre-processing software.

[0003] Foreign CAE pre-processing software (such as HyperMesh, ANSA) all have the function of rounded surface recognition, while domestic CAE pre-processing software is almost blank in this field. Even the industry-leading CAE pre-processing software HyperMesh still has problems such as inaccurate recognition and slow recognition speed for large models. Summary of the invention

[0004] The purpose of the present invention is to provide a rounded surface recognition method, device, equipment and medium based on a geometric model, so as to solve the problem that the recognition is not accurate enough and the recognition speed is slow when the rounded surface of the geometric model is recognized using the existing technology.

[0005] In order to solve the above technical problems, a technical solution adopted by the present invention is to provide a rounded surface recognition method based on a geometric model, and the method includes the following steps: performing virtual geometric processing on the edges of all faces in the geometric model to obtain transition edges on the recognition surface, the virtual geometric processing means treating multiple continuous short edges as a composite edge, and the transition edge belongs to the composite edge; determining that the recognition surface that meets the rounded corner feature is a transition surface; selecting two connecting surfaces connected to the transition surface, and the two connecting surfaces are respectively connected to the two ends of the transition edge, and determining that the two connecting surfaces that meet the support surface feature are respectively the first support surface and the second support surface, and the support surface feature is a feature unique to the two support surfaces connected by the rounded corner transition; determining that the transition surface that makes the first support surface and the second support surface transition smoothly is a rounded corner surface.

[0006] In some embodiments, before performing virtual geometry processing on the edges of all faces in the geometric model, the step of recording the subordinate relationship between the faces included in the geometric model and the geometric model is also included to obtain a face set, wherein the face set includes all faces of the geometric model.

[0007] In some embodiments, the virtual geometry processing of the edges of all faces in the face set to obtain the transition edges on the identified faces includes the steps of: storing multiple short edges that are sequentially connected and tangent to each other into a data container to form a composite edge; determining the first tangent vector and the second tangent vector corresponding to the two end points of the composite edge respectively; if there is an angle between the first tangent vector and the second tangent vector, determining the composite edge to be the transition edge.

[0008] In some embodiments, determining that the identification surface that meets the face fillet feature is a transition surface includes the steps of: calculating the face deflection angle and the radius of the face fillet of the identification surface, and keeping the face deflection angle and the radius of the face fillet within the expected range as the transition surface.

[0009] In some embodiments, the calculation of the surface deflection angle of the identification surface includes the steps of: determining the first tangent vector and the second tangent vector corresponding to the two endpoints of the transition edge respectively, constructing a cosine formula of the vector angle based on the first tangent vector and the second tangent vector, solving the vector angle therein, and obtaining the surface deflection angle.

[0010] In some embodiments, the determination of the two connecting surfaces that meet the support surface characteristics is respectively the first support surface and the second support surface, including the steps of: calculating the connecting surface normal vectors corresponding to the two connecting surfaces respectively; judging whether the two connecting surfaces meet the support surface characteristics based on whether the two connecting surface normal vectors are parallel vectors; wherein, if the two connecting surface normal vectors are parallel vectors, the two connecting surfaces are parallel to each other, and it is determined that the two connecting surfaces do not meet the support surface characteristics; if the two connecting surface normal vectors are not parallel vectors, the two connecting surfaces meet the support surface characteristics; if the two connecting surfaces meet the support surface characteristics, it is determined that the two connecting surfaces are respectively the first support surface and the second support surface.

[0011] In some embodiments, the determination that the transition surface that makes the first support surface and the second support surface transition smoothly is a rounded surface includes the steps of: calculating the transition surface normal vector of the transition surface, the transition surface normal vector includes a first normal vector and a second normal vector, the first normal vector is the normal vector on the common edge of the transition surface and the first support surface, and the second normal vector is the normal vector on the common edge of the transition surface and the second support surface; based on the transition surface normal vector and the support surface normal vectors corresponding to the first support surface and the second support surface, detecting whether the transition surface transitions smoothly with the first support surface and the second support surface, respectively.

[0012] The present invention also provides a rounded surface identification device based on a geometric model, the device comprising: a model processing unit, used to perform virtual geometric processing on the edges of all faces in the geometric model to obtain transition edges on the identification surface, the virtual geometric processing refers to treating multiple continuous short edges as a composite edge, and the transition edge belongs to the composite edge; a transition surface determination unit, used to determine that the identification surface that meets the rounded corner feature is a transition surface; a support surface determination unit, used to select two connecting surfaces connected to the transition surface, and the two connecting surfaces are respectively connected to the two ends of the transition edge, and the two connecting surfaces that meet the support surface feature are determined to be the first support surface and the second support surface, respectively, and the support surface feature is a feature unique to the two supporting surfaces connected by the rounded corner transition; a rounded surface determination unit, used to determine that the transition surface that makes a smooth transition between the first support surface and the second support surface is a rounded corner surface.

[0013] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the computer program.

[0014] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0015] The beneficial effects of the present invention are as follows: the present invention discloses a rounded corner surface recognition method, device, equipment and medium based on a geometric model, the method comprising the following steps: virtual geometry processing is performed on the edges of all faces in the geometric model to obtain transition edges on the recognition surface, virtual geometry processing refers to treating multiple continuous short edges as a composite edge, and the transition edge belongs to the composite edge; determining that the recognition surface that meets the rounded corner feature is a transition surface; selecting two connecting surfaces connected to the transition surface, and the two connecting surfaces are respectively connected to the two ends of the transition edge, and determining that the two connecting surfaces that meet the support surface feature are respectively the first support surface and the second support surface, and the support surface feature is a feature unique to the two support surfaces connected by the rounded corner surface transition; determining that the transition surface that makes the first support surface and the second support surface smoothly transition is a rounded corner surface. The rounded corner surface recognition method of the present invention can handle the situation of broken edges of rounded corner surfaces based on the idea of ​​virtual geometry, and does not need to calculate the analytical equation of the geometric surface. The rounded corner surface in the geometric model can be quickly recognized only through the information of the edge, which greatly speeds up the recognition process, and the recognition is highly accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flow chart of an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0017] Figure 2 It is a specific flow chart of step S1 in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0018] Figure 3 It is a partial schematic diagram of a geometric model used in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0019] Figure 4 yes Figure 3 A magnified view of area A;

[0020] Figure 5 It is a partial schematic diagram of a geometric model containing tangent vectors of a transition edge at two end points in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0021] Figure 6 It is a specific flow chart of step S3 in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0022] Figure 7 It is a partial schematic diagram of a geometric model containing a connection surface normal vector in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0023] Figure 8 It is a specific flow chart of step S4 in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0024] Fig. 9 It is a partial schematic diagram of a geometric model containing a normal vector of a transition surface in an embodiment of a fillet surface recognition method based on a geometric model of the present invention;

[0025] Fig.10 This is a recognition result diagram of an embodiment of a rounded surface recognition method based on a geometric model of the present invention;

[0026] Fig.11 This is a recognition result diagram of another embodiment of a rounded surface recognition method based on a geometric model of the present invention;

[0027] Fig.12 It is a structural block diagram of a rounded surface recognition device based on a geometric model of the present invention;

[0028] Fig.13 It is a schematic diagram of the structure of an electronic device according to an embodiment of the present invention;

[0029] Fig.14 It is a schematic block diagram of an embodiment of a computer-readable storage medium of the present invention. DETAILED DESCRIPTION

[0030] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. Preferred embodiments of the present invention are provided in the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0031] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0032] First of all, it should be pointed out that fillet surfaces are often used in CAD design to achieve a smooth transition between two adjacent or intersecting surfaces, ensuring that the edge transition of the geometric body is smoother and more natural. Therefore, common fillet surfaces in geometric models usually have the following characteristics: the fillet surface itself is smooth, without sharp edges / points inside; the fillet surface and the two connecting surfaces are G1 continuous with smooth transition, where G1 continuity is also called tangent continuity, which refers to the smooth transition between two objects; the fillet surface has at least one transition edge to achieve a smooth transition between the two connecting surfaces; the fillet surface is usually a cylindrical surface or a torus surface.

[0033] like Figure 1As shown, a fillet surface recognition method based on a geometric model of the present invention is shown, and the method comprises the following steps:

[0034] Step S1: Perform virtual geometry processing on the edges of all faces in the geometric model to obtain transition edges on the identified faces.

[0035] Before the edges of all faces in the geometric model are subjected to virtual geometry processing, the method further includes the steps of: recording the subordinate relationship between the faces included in the geometric model and the geometric model to obtain a face set, the face set including all faces of the geometric model, including a curved surface connecting two connected faces. Then, based on the face set, the edges of all faces in the face set can be subjected to virtual geometry processing in sequence.

[0036] It should be noted that virtual geometry processing is based on the idea of ​​virtual geometry (non-Euclidean geometry), which challenges and redefines the basic principles of geometry. Multiple continuous short edges are regarded as a composite edge, that is, multiple short edge data are combined into a virtual composite edge. Among them, there is no need to change the underlying data of multiple short edges. Just take a temporary combination of multiple short edges. The resulting composite edge can be regarded as a virtual set. Such an edge does not actually exist. The identification surface is the currently identified surface with multiple short edges. The transition edge is the edge of two connected surfaces located on the identification surface and connected to the identification surface at both ends. Since the transition edge on the rounded surface must not be a straight line, the transition edge belongs to a composite edge.

[0037] Among them, for all the faces in the face set, there is an identification face with multiple short edges. Check the tangent direction of each short edge at the endpoint. If there are multiple short edges that are connected and tangent in sequence, these short edges are stored in a data container, and virtual geometry processing is performed based on the virtual geometry idea to form a composite edge. At the same time, since the transition edge of the rounded face must not be a straight line, there is an angle between the tangent lines at the starting point and the end point. Therefore, it is necessary to judge whether there is an angle between the tangent directions of the composite edge at both end points, so as to determine the transition edge on the identification face.

[0038] Specifically, if Figure 2 As shown, step S1 includes the following sub-steps:

[0039] Step S11: storing a plurality of sequentially connected and tangent short edges into a data container to form a composite edge.

[0040] It should be noted that when a surface is identified to have multiple short edges, it is necessary to calculate the tangent of each short edge at its respective endpoint, and then determine whether the two connected short edges are tangent by the corresponding tangents of the two connected short edges at the intersection (the tangents at the corresponding endpoints of the short edges), and then determine whether the multiple short edges are sequentially connected and tangent, and finally put the multiple sequentially connected and tangent short edges into the same data container. The multiple short edges in this data container can be regarded as a composite edge. Among them, if the corresponding tangents of the two connected short edges at the intersection are the same, then the corresponding two short edges are connected and tangent, and the two short edges can be put into one data container.

[0041] like Figure 3-Figure 5 As shown, a geometric model 1 is shown, in which there are four connected short edges on an identification surface S, and the four short edges are connected in sequence through three intersections (J1, J2 and J3). First, the tangent directions of the four connected short edges at their respective endpoints are calculated respectively, and it is determined in sequence whether the tangent directions of two connected short edges at the corresponding intersections are the same. For the three intersections in the figure, if the tangent directions of every two connected short edges at the corresponding intersections are the same, that is, the four short edges are connected in sequence and tangent to each other, then the four short edges are stored in a data container, and the four short edges can form a composite edge 2.

[0042] In this embodiment, the four short sides are regarded as a composite side 2, and the surface deflection angle of the rounded surface can be obtained by calculating the side deflection angle of the composite side 2, so that the calculation of the surface deflection angle is more accurate.

[0043] Step S12: Determine the first tangent vector and the second tangent vector corresponding to the two end points of the composite edge respectively.

[0044] like Figure 5 As shown, the first tangent vector corresponding to the two end points of the composite edge 2 is shown. and the second tangent vector

[0045] Step S13: If there is an angle between the first tangent vector and the second tangent vector, the composite edge is determined to be a transition edge.

[0046] like Figure 5 As shown, it is clear that the first tangent vector and the second tangent vector There is an angle between them, so composite edge 2 is a transition edge.

[0047] In this embodiment, after the transition edge is obtained, the required rounded corner surface can be identified through the length and deflection direction of the transition edge.

[0048] Step S2: Determine the identified surface that meets the surface fillet feature as the transition surface.

[0049] It should be noted that the face fillet feature is a feature used to blend non-adjacent, non-continuous faces. It allows the user to specify a common fillet radius for two or more faces, thereby creating a smooth transition effect between the faces. The implementation of the face fillet feature is based on selecting two or more faces and specifying a common fillet radius. Therefore, the face fillet feature includes the face deflection angle of the fillet face and the radius of the corresponding face fillet, both of which are within a specific range. In this application, the identification surface that meets the face fillet feature means that the face deflection angle and the radius of the face fillet of the identification surface are within the expected range. The face fillet can be regarded as the deflection angle of the fillet face, and the angle of the face fillet is equal to the radian of the transition edge. Afterwards, by calculating the face deflection angle and the radius of the face fillet of the identification surface, the identification surface whose face deflection angle and the radius of the face fillet are within the expected range are retained as the transition surface.

[0050] In most cases, the change angle of the fillet surface is replaced by the change angle of the transition edge, that is, the surface deflection angle is equal to the edge deflection angle of the transition edge. Therefore, when calculating the surface deflection angle of the identified surface, the steps include: determining the first tangent vector and the second tangent vector corresponding to the two end points of the transition edge, respectively, constructing the cosine formula of the vector angle based on the first tangent vector and the second tangent vector, solving the vector angle therein, and obtaining the edge deflection angle.

[0051] Among them, the cosine formula of the vector angle is:

[0052]

[0053] Where θ is the first tangent vector and the second tangent vector The vector angle between them corresponds to the edge deflection angle of 180°-θ.

[0054] In this embodiment, the expected range of the surface deflection angle is between 15° and 150°, that is, the transition edge with an edge deflection angle between 15° and 150° meets user expectations.

[0055] It should be noted that if the edge deflection angle is less than 15°, the recognition surface is approximately a plane; and if the edge deflection angle exceeds 150°, a smooth transition between the transition surface and the connection surface cannot be guaranteed. Therefore, the recognition surface corresponding to the edge deflection angle of 15°-150° is reserved as the transition surface, and the recognition surface exceeding the angle range of 15°-150° is not within the range that needs to be recognized.

[0056] Secondly, the radius of the face fillet is the ratio of the length L of the transition edge to the edge deflection angle 180°-θ of the transition edge, that is, the radius of the face fillet is R=L / (180°-θ). The radius R of the face fillet is compared with the user input value, and the recognition face within the user's expected range is selected as the transition face.

[0057] In this process, by controlling the parameters of the edge deflection angle of the transition edge and the radius of the face fillet, the face fillet features in the geometric model can be quickly identified, and the identified surface that meets the face fillet features can be determined as the transition surface, ensuring that the fillet surface determined later meets actual needs.

[0058] Step S3: Select two connection surfaces connected to the transition surface, and the two connection surfaces are respectively connected to the two ends of the transition edge, and determine that the two connection surfaces that meet the support surface characteristics are the first support surface and the second support surface.

[0059] It should be noted that the support surface feature is a basic feature unique to two support surfaces transitionally connected by a fillet surface, including that the two support surfaces are non-parallel.

[0060] Among them, the two connecting surfaces connected by the transition edge respectively coincide with the transition surface and have two common edges. The connecting surface normal vectors of the two connecting surfaces on the two common edges are calculated. If the two connecting surface normal vectors are parallel, the two connecting surfaces are parallel or coincide with each other, and the transition surface and the two connecting surfaces may belong to the same surface; if there is an angle between the two connecting surface normal vectors, the two connecting surfaces are not parallel to each other, and the transition surface and the two connecting surfaces must not belong to the same surface, so that the situation where the transition edge is a plane curve can be screened and removed.

[0061] Specifically, if Figure 6 As shown, step S3 includes the following sub-steps:

[0062] Step S31: Calculate the connection surface normal vectors corresponding to the two connection surfaces respectively.

[0063] In this embodiment, if Figure 7 As shown in FIG. 1 , for two connecting surfaces (L1 and L2), the midpoint of the common edge between the connecting surface (L1 / L2) and the transition surface M is taken, and the connecting surface normal vector of the midpoint on the corresponding connecting surface (L1 / L2) is calculated. The two connecting surface normal vectors are respectively

[0065] In some other embodiments, other points on the common edge may be taken to calculate the connection surface normal vectors of the other points on the corresponding connection surface.

[0066] Step S32: Based on whether the normal vectors of the two connecting surfaces are parallel vectors, determine whether the two connecting surfaces meet the support surface characteristics.

[0067] When the two connection surfaces are parallel to each other, it is determined that the two connection surfaces do not meet the support surface feature. If the normal vectors of the two connection surfaces are parallel vectors, the two connection surfaces are parallel to each other, and it is determined that the two connection surfaces do not meet the support surface feature; if the normal vectors of the two connection surfaces are not parallel vectors, the two connection surfaces meet the support surface feature, and the process proceeds to step S33.

[0068] Step S33: If the two connection surfaces meet the support surface characteristics, the two connection surfaces are determined to be the first support surface and the second support surface respectively.

[0069] like Figure 7 and Fig. 9 As shown, the normal vectors of the two connecting surfaces are It is not a parallel vector, and the corresponding two connecting surfaces (L1 and L2) meet the support surface characteristics. It is determined that the two connecting surfaces (L1 and L2) are the first support surface D1 and the second support surface D2 respectively.

[0070] In this embodiment, by selecting two connection surfaces that meet the support surface characteristics as the first support surface D1 and the second support surface D2 through step S3 and step S4, it can be ensured that the two support surfaces obtained are non-parallel.

[0071] Step S4: Determine that the transition surface that enables smooth transition between the first supporting surface and the second supporting surface is a rounded surface.

[0072] The normal vectors corresponding to the transition surface, the first supporting surface and the second supporting surface are calculated, and it is determined whether the transition surface smoothly transitions with the first supporting surface and the second supporting surface respectively according to the corresponding normal vectors.

[0073] Specifically, if Figure 8 As shown, step S4 includes the following sub-steps:

[0074] Step S41: Calculate the transition surface normal vector of the transition surface.

[0075] like Fig. 9 As shown, the transition surface normal vector includes the first normal vector and the second normal vector First normal vector is the normal vector of the transition surface M on the common edge where the transition surface M and the first support surface D1 coincide, and the second normal vector It is the normal vector of the transition surface M on the common edge where the transition surface M and the second supporting surface D2 coincide.

[0076] In this embodiment, the first normal vector is obtained by taking the midpoint of the common edge. and the second normal vector

[0077] Step S42: Based on the normal vector of the transition surface and the support surface normal vectors of the first support surface and the second support surface, detect whether the transition surface transitions smoothly with the first support surface and the second support surface respectively.

[0078] It should be noted that the support surface normal vectors of the first support surface and the second support surface correspond to the two connection surface normal vectors mentioned in step S3 respectively.

[0079] In this embodiment, combined with Figure 7 , the support surface normal vectors of the first support surface D1 and the second support surface D2 are If the support surface normal vector of the first support surface D1 With the first normal vector There is an angle between them, and / or the normal vector of the second support surface D2 support surface and the second normal vector If there is an angle between the transition surface M and the first support surface D1 and / or the second support surface D2, it means that the transition surface M is not smoothly transitioned with the first support surface D1 and / or the second support surface D2, and the corresponding transition surface M is not a rounded surface; if the support surface normal vector of the first support surface D1 With the first normal vector Coincident, the normal vector of the second support surface D2 With the second normal vector If they coincide, it indicates that the transition surface M transitions smoothly with the first supporting surface D1 and the second supporting surface D2 respectively, and the corresponding transition surface M is a rounded surface.

[0080] It should be noted that, because the points selected when calculating the support surface normal vector and the transition surface normal vector are all the midpoints of the common edge, if the support surface normal vector of the first support surface D1 is With the first normal vector Coincident, the support surface normal vector of the second support surface D2 With the second normal vector The overlap indicates that the transition surface M transitions smoothly with the first supporting surface D1 and the second supporting surface D2 respectively.

[0081] In some other embodiments, when calculating the support surface normal vector and the transition surface normal vector, other points other than the midpoint of the common edge may be selected. If the selected points are different, the support surface normal vector of the first support surface D1 is calculated. With the first normal vector Parallel to each other, the support surface normal vector of the second support surface D2 With the second normal vector They are parallel to each other, and a transition surface M is determined to smoothly transition with the first supporting surface D1 and the second supporting surface D2 respectively.

[0082] like Fig.10 and Fig.11 As shown, multiple rounded surfaces in two geometric models identified by the rounded surface identification method of the present application are shown, and each rounded surface is highlighted in blue. The transition between each rounded surface and the corresponding two connecting surfaces is achieved through G1 continuity, ensuring a smooth visual transition without a sudden sense of interruption.

[0083] Based on the same inventive concept, Fig.12 As shown, the present invention also provides a rounded surface recognition device based on a geometric model, the device comprising:

[0084] The model processing unit 101 is used to perform virtual geometry processing on the edges of all faces in the geometric model to obtain transition edges on the identified faces. Virtual geometry processing refers to treating multiple continuous short edges as a composite edge, and the transition edge belongs to the composite edge.

[0085] The transition surface determination unit 102 is used to determine the identified surface that meets the surface rounding feature as a transition surface.

[0086] The support surface determination unit 103 is used to select two connection surfaces connected to the transition surface, and the two connection surfaces are respectively connected to the two ends of the transition edge, and determine that the two connection surfaces that meet the support surface characteristics are respectively the first support surface and the second support surface, and the support surface characteristics are the unique characteristics of the two support surfaces connected by the rounded surface transition.

[0087] The rounded surface determining unit 104 is used to determine that a transition surface that enables a smooth transition between the first supporting surface and the second supporting surface is a rounded surface.

[0088] In the present application, other technical features of the above-mentioned rounded surface recognition device based on geometric model are the same as the features disclosed in the above-mentioned method embodiment, and will not be repeated here.

[0089] Based on the same inventive concept, the present application also provides an electronic device, which includes a processor, a memory and a communication circuit, and the processor is connected to the memory and the communication circuit respectively; wherein the communication circuit is used for communication connection, the memory is used to store a computer program, and the processor is used to execute the computer program to implement the above method.

[0090] See also Fig.13 The electronic device described in the embodiment of the present application may specifically include a processor 210 and a memory 220. The memory 220 is coupled to the processor 210.

[0091] The processor 210 is used to control the operation of the electronic device. The processor 210 may also be referred to as a CPU (Central Processing Unit). The processor 210 may be an integrated circuit chip having the ability to process signals. The processor 210 may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. A general-purpose processor may be a microprocessor or the processor 210 may also be any conventional processor, etc.

[0092] The memory 220 is used to store computer programs, and may be a RAM, a ROM, or other types of storage terminals. Specifically, the memory 220 may include one or more computer-readable storage media, which may be non-transitory or transient. The memory 220 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage terminals, flash memory storage terminals. In some embodiments, the non-transitory computer-readable storage medium in the memory 220 is used to store at least one program code.

[0093] The processor 210 is used to execute the computer program stored in the memory 220 to implement the methods described in the various method embodiments of the present application.

[0094] In some embodiments, the electronic device may further include: a peripheral terminal interface 230 and at least one peripheral terminal. The processor 210, the memory 220 and the peripheral terminal interface 230 may be connected via a bus or a signal line. Each peripheral terminal may be connected to the peripheral terminal interface 230 via a bus, a signal line or a circuit board. Specifically, the peripheral terminal includes: at least one of a radio frequency circuit 240, a display screen 250, an audio circuit 260 and a power supply 270.

[0095] The peripheral terminal interface 230 may be used to connect at least one peripheral terminal related to I / O (Input / output) to the processor 210 and the memory 220. In some embodiments, the processor 210, the memory 220, and the peripheral terminal interface 230 are integrated on the same chip or circuit board; in some other implementations, any one or two of the processor 210, the memory 220, and the peripheral terminal interface 230 may be implemented on a separate chip or circuit board, which is not limited in this embodiment.

[0096] The radio frequency circuit 240 is used to receive and transmit RF (Radio Frequency) signals, also known as electromagnetic signals. The radio frequency circuit 240 communicates with the communication network and other IoT devices through electromagnetic signals, and the radio frequency circuit 240 is the communication circuit of the electronic device. The radio frequency circuit 240 converts the electrical signal into an electromagnetic signal for transmission, or converts the received electromagnetic signal into an electrical signal. Optionally, the radio frequency circuit 240 includes: an antenna system, an RF transceiver, one or more amplifiers, a tuner, an oscillator, a digital signal processor, a codec chipset, an operator identity module card, and the like. The radio frequency circuit 240 can communicate with other terminals through at least one wireless communication protocol. The wireless communication protocol includes, but is not limited to: the World Wide Web, a metropolitan area network, an intranet, various generations of mobile communication networks (2G, 3G, 4G and 5G), a wireless local area network and / or a WiFi (Wireless Fidelity) network. In some embodiments, the radio frequency circuit 240 may also include circuits related to NFC (Near Field Communication), which is not limited in this application.

[0097] The display screen 250 is used to display the UI (User Interface). The UI may include graphics, text, icons, videos, and any combination thereof. When the display screen 250 is a touch display screen, the display screen 250 also has the ability to collect touch signals on the surface or above the surface of the display screen 250. The touch signal can be input to the processor 210 as a control signal for processing. At this time, the display screen 250 can also be used to provide virtual buttons and / or virtual keyboards, also known as soft buttons and / or soft keyboards. In some embodiments, the display screen 250 can be one, set on the front panel of the electronic device; in other embodiments, the display screen 250 can be at least two, respectively set on different surfaces of the electronic device or in a folding design; in other embodiments, the display screen 250 can be a flexible display screen, set on a curved surface or a folding surface of the electronic device. Even, the display screen 250 can also be set to a non-rectangular irregular shape, that is, a special-shaped screen. The display screen 250 can be made of materials such as LCD (Liquid Crystal Display), OLED (Organic Light-Emitting Diode, organic light-emitting diode).

[0098] The audio circuit 260 may include a microphone and a speaker. The microphone is used to collect sound waves from the operator and the environment, and convert the sound waves into electrical signals and input them into the processor 210 for processing, or input them into the radio frequency circuit 240 to achieve voice communication. For the purpose of stereo acquisition or noise reduction, there may be multiple microphones, which are respectively arranged in different parts of the electronic device. The microphone may also be an array microphone or an omnidirectional acquisition microphone. The speaker is used to convert the electrical signal from the processor 210 or the radio frequency circuit 240 into sound waves. The speaker may be a traditional film speaker or a piezoelectric ceramic speaker. When the speaker is a piezoelectric ceramic speaker, it can not only convert the electrical signal into sound waves audible to humans, but also convert the electrical signal into sound waves inaudible to humans for purposes such as ranging. In some embodiments, the audio circuit 260 may also include a headphone jack.

[0099] The power supply 270 is used to power various components in the electronic device. The power supply 270 can be an alternating current, a direct current, a disposable battery, or a rechargeable battery. When the power supply 270 includes a rechargeable battery, the rechargeable battery can be a wired rechargeable battery or a wireless rechargeable battery. A wired rechargeable battery is a battery that is charged through a wired line, and a wireless rechargeable battery is a battery that is charged through a wireless coil. The rechargeable battery can also be used to support fast charging technology.

[0100] For a detailed description of the functions and execution processes of each functional module or component in the electronic device embodiment of the present application, reference can be made to the description in the above-mentioned method embodiments of the present application, which will not be repeated here.

[0101] In the several embodiments provided in the present application, it should be understood that the disclosed electronic devices and methods can be implemented in other ways. For example, the various embodiments of the electronic devices described above are only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0102] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0103] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0104] Based on the same inventive concept, the present application also provides a computer-readable storage medium storing a computer program, which can be executed by a processor to implement the above method.

[0105] See also Fig.14 , if the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium 300. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions / computer programs to enable an IoT device (which can be a personal computer, server, or network terminal, etc.) or a processor (processor) to perform all or part of the steps of each implementation method of the present application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks or optical disks, and electronic terminals such as computers, mobile phones, laptops, tablet computers, cameras, etc. having the above-mentioned storage media.

[0106] The description of the execution process of the program data in the computer-readable storage medium can refer to the description in the above-mentioned method embodiments of the present application, and will not be repeated here.

[0107] It can be seen that the present invention discloses a rounded surface recognition method, device, equipment and medium based on a geometric model. The method includes the following steps: virtual geometry processing is performed on the edges of all faces in the geometric model to obtain transition edges on the recognition surface. Virtual geometry processing refers to treating multiple continuous short edges as a composite edge, and the transition edge belongs to the composite edge; determining that the recognition surface that meets the rounded corner feature is a transition surface; selecting two connecting surfaces connected to the transition surface, and the two connecting surfaces are respectively connected to the two ends of the transition edge, and determining that the two connecting surfaces that meet the support surface feature are respectively the first support surface and the second support surface, and the support surface feature is a feature unique to the two support surfaces connected by the rounded surface transition; determining that the transition surface that makes the first support surface and the second support surface smoothly transition is a rounded surface. The rounded surface recognition method of the present invention can handle the situation of broken edges of rounded surfaces based on the idea of ​​virtual geometry. It does not need to calculate the analytical equation of the geometric surface. The rounded surface in the geometric model can be quickly recognized only through the information of the edge, which greatly speeds up the recognition process and is highly accurate.

[0108] The above are only embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any equivalent structural transformations made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are included in the protection scope of the present invention.

Claims

1. A rounded surface recognition method based on a geometric model, characterized in that: The method comprises the following steps: Performing virtual geometry processing on the edges of all faces in the geometric model to obtain transition edges on the identified faces, wherein the virtual geometry processing refers to treating multiple continuous short edges as a composite edge, and the transition edges belong to the composite edge; Determining the identified surface that meets the surface fillet feature as a transition surface; Select two connecting surfaces connected to the transition surface, and the two connecting surfaces are respectively connected to the two ends of the transition edge, and determine that the two connecting surfaces that meet the support surface characteristics are respectively the first support surface and the second support surface, and the support surface characteristics are the characteristics unique to the two support surfaces connected by the fillet surface transition; The transition surface that enables smooth transition between the first supporting surface and the second supporting surface is determined to be a rounded surface.

2. The rounded surface recognition method according to claim 1, characterized in that: Before the virtual geometry processing is performed on the edges of all faces in the geometric model, the method further includes the following steps: The subordinate relationship between the faces included in the geometric model and the geometric model is recorded to obtain a face set, where the face set includes all the faces of the geometric model.

3. The rounded surface recognition method according to claim 1, characterized in that: The virtual geometry processing is performed on the edges of all the faces in the face set to obtain transition edges on the identified faces, comprising the steps of: Store multiple sequentially connected and tangent short edges into a data container to form a composite edge; Determine a first tangent vector and a second tangent vector corresponding to the two end points of the composite edge respectively; If there is an angle between the first tangent vector and the second tangent vector, the composite edge is determined to be the transition edge.

4. The rounded surface recognition method according to claim 1, characterized in that: The step of determining that the identified surface that meets the surface fillet feature is a transition surface comprises the steps of: The surface deflection angle and the radius of the surface fillet of the identification surface are calculated, and the identification surface whose surface deflection angle and the radius of the surface fillet are within the expected range is retained as a transition surface.

5. The rounded surface recognition method according to claim 4, characterized in that: The step of calculating the surface deflection angle of the identification surface comprises the following steps: Determine the first tangent vector and the second tangent vector respectively corresponding to the two endpoints of the transition edge, construct a cosine formula of the vector angle based on the first tangent vector and the second tangent vector, solve the vector angle therein, and obtain the surface deflection angle.

6. The rounded surface recognition method according to claim 1, characterized in that: The step of determining that the two connection surfaces meeting the support surface characteristics are respectively the first support surface and the second support surface comprises the following steps: Calculating the connection surface normal vectors respectively corresponding to the two connection surfaces; Based on whether the two connection surface normal vectors are parallel vectors, judging whether the two connection surfaces meet the support surface feature; wherein, if the two connection surface normal vectors are parallel vectors, the two connection surfaces are parallel to each other, and it is determined that the two connection surfaces do not meet the support surface feature; if the two connection surface normal vectors are not parallel vectors, the two connection surfaces meet the support surface feature; If the two connection surfaces meet the support surface characteristics, it is determined that the two connection surfaces are respectively the first support surface and the second support surface.

7. The rounded surface recognition method according to claim 1, characterized in that: The step of determining that the transition surface that enables a smooth transition between the first supporting surface and the second supporting surface is a rounded surface comprises the steps of: Calculating a transition surface normal vector of the transition surface, wherein the transition surface normal vector includes a first normal vector and a second normal vector, wherein the first normal vector is a normal vector on a common edge of the transition surface and the first supporting surface, and the second normal vector is a normal vector on a common edge of the transition surface and the second supporting surface; Based on the normal vector of the transition surface and the normal vectors of the supporting surfaces corresponding to the first supporting surface and the second supporting surface, it is detected whether the transition surface smoothly transitions with the first supporting surface and the second supporting surface respectively.

8. A rounded surface recognition device based on a geometric model, characterized in that: The device comprises: A model processing unit, used for performing virtual geometry processing on the edges of all faces in the geometric model to obtain transition edges on the identified faces, wherein the virtual geometry processing refers to treating multiple continuous short edges as a composite edge, and the transition edge belongs to the composite edge; A transition surface determination unit, used to determine that the identified surface that meets the surface fillet feature is a transition surface; A support surface determination unit, used for selecting two connection surfaces connected to the transition surface, wherein the two connection surfaces are respectively connected to two ends of the transition edge, and determining that the two connection surfaces meeting the support surface feature are respectively the first support surface and the second support surface, wherein the support surface feature is a feature unique to the two support surfaces connected by the fillet surface transition; The rounded surface determining unit is used to determine that the transition surface that enables a smooth transition between the first supporting surface and the second supporting surface is a rounded surface.

9. An electronic device, characterized in that: The method comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images