CN117606363A

CN117606363A - Non-contact gap measurement method and system based on convex hull and gravity center projection

Info

Publication number: CN117606363A
Application number: CN202311609883.1A
Authority: CN
Inventors: 付吉祥; 潘威; 谷宏亮; 曹玲; 卢盛林
Original assignee: Guangdong OPT Machine Vision Co Ltd
Current assignee: Guangdong OPT Machine Vision Co Ltd
Priority date: 2023-11-28
Filing date: 2023-11-28
Publication date: 2024-02-27

Abstract

The invention relates to the technical field of gap measurement, and discloses a non-contact type gap measurement method and a non-contact type gap measurement system based on convex hull and gravity center projection.

Description

Non-contact gap measurement method and system based on convex hull and gravity center projection

Technical Field

The invention relates to the technical field of gap measurement, in particular to a non-contact gap measurement method and system based on convex hulls and gravity center projection.

Background

Gap measurement is a very important detection item in industrial production, and whether the size of a gap is qualified or not directly influences the quality of a workpiece.

Currently, the existing solutions generally use a feeler gauge (also called a slit gauge) to measure the slit size. During measurement, the workpiece is required to be contacted with the mirror surface, then a proper feeler gauge is selected from feelers of different specifications to be inserted into a gap between the workpiece and the mirror surface until the feeler gauge cannot be inserted continuously, and the reading at the moment is the size of the gap. The problems with this solution are: (1) multiple operations are needed, and the efficiency is low; (2) when impurities such as stains exist on the mirror surface, misjudgment is easy; (3) Depending largely on the hand and experience of the measurer, it is very difficult to have precise control over the quality of the measurement.

Accordingly, improvements in the art are needed.

The above information is presented as background information only to aid in the understanding of the present disclosure and is not intended or admitted to be prior art relative to the present disclosure.

Disclosure of Invention

The invention provides a non-contact slit measurement method and a non-contact slit measurement system based on convex hulls and gravity center projection, which are used for solving the problems in the prior art.

In order to achieve the above object, the present invention provides the following technical solutions:

in a first aspect, the present invention provides a non-contact slit measurement method based on convex hull and gravity center projection, the method comprising:

inputting a depth image, taking out a point set, and preprocessing the point set to obtain a preprocessed point set;

connectivity segmentation is carried out on the preprocessed point set, different areas are segmented, main areas are extracted, and ROI following is set;

extracting a point set of a main area, and performing rapid convex hull detection to obtain points of outer layers of the point set, wherein the points of the adjacent three outer layers are connected to form a convex polyhedron;

adding weights to the point sets of different areas according to the preprocessed point sets, and calculating the gravity centers according to the following weighted gravity center formula:

the gravity center projects along the gravity direction, and a supporting surface is determined according to the position relation between the projection point and the convex hull surface;

and selecting a point on the measured surface, and calculating the distance between the point and the supporting surface to obtain the size of the gap.

Further, in the non-contact slit measurement method based on convex hull and gravity center projection, the step of inputting the depth image, taking out a point set, preprocessing the point set, and obtaining the preprocessed point set includes:

inputting a depth image and taking out a point set;

in the point set, cleaning based on the number of fields, taking the points with the radius of a being equal to b and the surrounding of which is not more than c points as noise points, and cleaning the noise points;

in the point set, based on histogram cleaning, the height is divided into d bins, the bins with the number of points less than e% are regarded as noise points, and the noise points are cleaned, so that the preprocessed point set is obtained.

Further, in the non-contact slit measurement method based on projection of the convex hull and the gravity center, the gravity center is projected along the gravity direction, and the step of determining the supporting surface according to the positional relationship between the projection point and the convex hull surface comprises the following steps:

the gravity center projects along the gravity direction, the position relation between the projection point and the convex hull surface is judged, and if the projection point is in a certain triangular surface, the triangular surface where the projection point is positioned is determined to be a supporting surface; if the projection points are on the edges of the triangular surfaces, determining the triangular surface with the largest area as a supporting surface; if the projection point is on the vertex of the triangular surfaces, the triangular surface with the largest area is determined as the supporting surface.

Further, in the non-contact slit measurement method based on convex hull and gravity center projection, the step of selecting a point on the measured surface, calculating a distance from the point to the supporting surface, and obtaining the size of the slit includes:

selecting a plurality of points on the measured surface;

and respectively calculating the distance from each point to the supporting surface, and calculating the average value to obtain the size of the gap.

In a second aspect, the present invention provides a non-contact slit measurement system based on convex hull and gravity center projection, the system comprising:

the point set acquisition module is used for inputting the depth image, taking out the point set, and preprocessing the point set to obtain a preprocessed point set;

the region segmentation module is used for carrying out connectivity segmentation on the preprocessed point set, segmenting out different regions, extracting a main region and setting a region of interest (ROI) to follow;

the convex hull detection module is used for extracting a point set of a main area, and carrying out rapid convex hull detection to obtain points of outer layers of the point set, wherein the points of the adjacent three outer layers are connected to form a convex polyhedron;

the gravity center calculating module is used for adding weights to the point sets of different areas according to the preprocessed point sets and calculating the gravity center according to the following weighted gravity center formula:

the supporting surface determining module is used for projecting the gravity center along the gravity direction and determining a supporting surface according to the position relation between the projection point and the convex hull surface;

and the gap calculating module is used for selecting points on the measured surface, calculating the distance between the points and the supporting surface and obtaining the size of the gap.

Further, in the non-contact slit measurement system based on convex hull and gravity center projection, the point set acquisition module is specifically configured to:

inputting a depth image and taking out a point set;

Further, in the non-contact gap measurement system based on convex hull and gravity center projection, the supporting surface determining module is specifically configured to:

Further, in the non-contact slit measurement system based on convex hull and gravity center projection, the slit calculation module is specifically configured to:

selecting a plurality of points on the measured surface;

In a third aspect, the present invention provides a computer device, including a memory and a processor, where the memory stores a computer program, and the processor implements the non-contact slit measurement method based on convex hull and gravity center projection according to the first aspect when executing the computer program.

In a fourth aspect, the present invention provides a storage medium containing computer executable instructions for execution by a computer processor to implement the convex hull and center of gravity projection based non-contact gap measurement method of the first aspect.

Compared with the prior art, the invention has the following beneficial effects:

according to the non-contact gap measurement method and system based on the convex hull and the gravity center projection, the three-dimensional data of the workpiece collected from the front is input, the near-real supporting surface is obtained by means of the convex hull and the gravity center projection, the size of the gap can be calculated finally, the method and system are rapid and accurate, the measured quality can be accurately controlled, and the method and system are beneficial to popularization and application in a large range.

The invention has other features and advantages which will be apparent from or are set forth in detail in the accompanying drawings and the following detailed description, which are incorporated herein, taken in conjunction with the accompanying drawings and the detailed description, which illustrate certain principles of the invention.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic flow chart of a non-contact slit measurement method based on convex hull and gravity center projection according to a first embodiment of the present invention;

FIG. 2 is a schematic diagram of a 3D camera according to an embodiment of the present invention;

FIG. 3 is a schematic view of a workpiece according to an embodiment of the invention;

FIG. 4 is a schematic diagram of an input depth image according to an embodiment of the present invention;

FIG. 5 is a schematic illustration of a set of points fetched in accordance with an embodiment of the present invention;

FIG. 6 is a schematic diagram of outliers and noise removal in accordance with an embodiment of the present invention;

FIG. 7 is a schematic diagram of the extraction of a main area according to the first embodiment of the present invention;

FIG. 8 is a schematic view of a convex polyhedron constructed in accordance with an embodiment of the present invention;

FIG. 9 is a schematic illustration of a cleaned point set calculation center of gravity in accordance with an embodiment of the present invention;

FIG. 10 is a schematic view of a center of gravity projected onto a convex hull surface in accordance with an embodiment of the present invention;

FIG. 11 is a schematic illustration of a plane defined by a triangular surface in accordance with an embodiment of the present invention;

FIG. 12 is a schematic view of a point cloud flip from a side view of a support surface in accordance with an embodiment of the present invention;

FIG. 13 is a schematic illustration of a real view of a workpiece in accordance with an embodiment of the invention;

FIG. 14 is a schematic view of a projection view of a convex hull of another workpiece in accordance with an embodiment of the invention;

FIG. 15 is a schematic illustration of a side view of another workpiece in accordance with an embodiment of the invention;

FIG. 16 is a schematic illustration of a real view of another workpiece in accordance with an embodiment of the invention;

FIG. 17 is a schematic diagram of a comparison result of manual sorting according to the first embodiment of the present invention;

fig. 18 is a schematic diagram of a functional module of a non-contact slit measurement system based on convex hull and gravity center projection according to a second embodiment of the present invention;

fig. 19 is a schematic structural diagram of a computer device according to a third embodiment of the present invention.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure. In addition, as one of ordinary skill in the art can appreciate, with technical development and new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

In the description of the present application, it is to be understood that all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs unless defined otherwise. Furthermore, any terminology used is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

In addition, numerous specific details are set forth in the following detailed description in order to provide a better understanding of the present application. It will be understood by those skilled in the art that the present application may be practiced without some of these specific details. In some instances, methods, means, elements, and circuits have not been described in detail as not to unnecessarily obscure the present application.

The technical scheme of the invention is further described below by the specific embodiments with reference to the accompanying drawings.

Example 1

In view of the above-mentioned drawbacks of the prior art, the applicant has actively studied and innovated based on the fact that the design and manufacture of such products have been performed for many years and in combination with the application of the theory, so as to hope to create a technology capable of solving the drawbacks of the prior art, so that the slit measuring technology has more practicability. After continuous research and design and repeated sample test and improvement, the invention with practical value is finally created.

Specifically, in order to overcome the defects of a contact type gap measuring method, the invention provides a non-contact type gap measuring method, and only a 3D camera is used for collecting the front surface of a workpiece, so that the gap between the workpiece and a mirror surface can be simulated, the gap can be measured rapidly, accurately and completely, and a judgment result is given.

For three-dimensional data of an object collected from the front surface, a supporting point between the object and the mirror surface cannot be directly found, a graph surface formed by connecting the supporting points is known as a supporting surface, the object stability is based on the fact that the gravity center projection is required to fall on the supporting surface, and the larger the area of the supporting surface is, the stronger the stability of the object is. Due to the limitation of the sensor, a plurality of data such as outliers, noise points, environmental points, non-target area points and the like can exist in the measuring area, and the acquisition of a real supporting surface result is greatly influenced.

The invention acquires a near-real supporting surface by means of convex hull and gravity center projection. The convex hull is formed by connecting points of the outermost layers of points of a given three-dimensional space to form a convex polyhedron, which is commonly used for simulating contact between objects, and then the gravity center is projected along the gravity direction to fall on one surface of the convex hull, namely the required supporting surface. Because the convex hull is sensitive to noise, the data needs to be cleaned for a plurality of times before the convex hull is obtained.

Referring to fig. 1, a flow chart of a non-contact slit measurement method based on convex hull and gravity center projection according to an embodiment of the present invention is provided, and the method is applicable to a scene of slit measurement. The method specifically comprises the following steps:

s101, inputting a depth image, taking out a point set, and preprocessing the point set to obtain a preprocessed point set.

It should be noted that, the depth image input in this step is obtained by front-collecting the workpiece by the 3D camera, and the stability of the detection of the convex hull at the back is ensured by the processing procedure performed on the point set in advance.

In this embodiment, this step may be further refined to include the following steps:

inputting a depth image and taking out a point set;

It will be appreciated that a, b, c, d and e mentioned above are each set by the skilled person through experience, which is based on specific experimental results and may be any number.

S102, performing connectivity segmentation on the preprocessed point set, segmenting out different areas, extracting a main area, and setting a ROI to follow.

S103, extracting a point set of the main area, and carrying out rapid convex hull detection to obtain points of outer layers of the point set, wherein the points of the adjacent three outer layers are connected to form a convex polyhedron.

It should be noted that, the conventional convex hull detection method mainly includes a gift wrapping algorithm, an increment algorithm, a fast convex hull algorithm, and a divide-and-conquer algorithm. The present embodiment uses a fast convex hull algorithm.

S104, adding weights to the point sets of different areas according to the preprocessed point sets, and calculating the gravity centers according to the following weighted gravity center formula:

in this step, the center of gravity is calculated from the point set preprocessed in step S101, and weights are required to be added to the point sets in different regions in order to accurately calculate the position of the center of gravity.

In the step, weights are given to different areas, the weights play a role in adjusting the relative positions of the gravity centers and the different areas, for example, part of the areas are iron, the other areas are plastic, the gravity centers can be closer to one heavy side by adding the weights, and then the total gravity center is calculated.

It will be appreciated that in equation (3) above, the numerator is the sum of the density of each point and the product of the z-coordinates of that point, where, as exemplified by the first summation of the numerator, n1 represents the number of points of density p1 and Zi represents the z-coordinates of the corresponding point. The denominator is the sum of the densities of all points. The above formulas (1) and (2) are the same.

S105, projecting the gravity center along the gravity direction, and determining the supporting surface according to the position relation between the projection point and the convex hull surface.

It should be noted that, generally, the gravity direction on the earth is vertically downward, the coordinates of the point cloud are relative to a certain coordinate system, and as long as the acquisition environment is determined, the coordinate system is fixed, then the relationship with the gravity direction is determined, so that the gravity direction in the point cloud is obtained.

According to the embodiment, the gravity center is projected on the convex hull surface along the gravity direction, so that a real physical rule can be simulated, and a supporting surface close to the real supporting surface is obtained.

The positional relationship between the projection point and the convex hull surface comprises that the projection point is in a certain triangular surface, the projection point is on the edge of a plurality of triangular surfaces, and the projection point is on the vertex of a plurality of triangular surfaces.

Correspondingly, in the present embodiment, this step may be further refined to include the following steps:

S106, selecting points on the measured surface, and calculating the distance between the points and the supporting surface to obtain the size of the gap.

selecting a plurality of points on the measured surface;

In order to verify the feasibility of the present embodiment providing scheme, a detailed description will be given next with a specific example.

As shown in fig. 2, a depth map of the workpiece shown in fig. 3 is acquired by a 3D camera front surface.

Step one, inputting a depth image as shown in fig. 4, taking out a point set as shown in fig. 5, removing outliers and noise points as shown in fig. 6, and adopting a domain number cleaning and a histogram-based cleaning by a cleaning algorithm, wherein the domain number cleaning takes points with the domain of 5 and the radius of 1 and with the periphery of not more than 22 points as noise points, and the histogram-based cleaning takes bins with the height of 20 bins and the number of points of less than 0.05% as noise points.

And secondly, performing connectivity segmentation on the preprocessed depth map, segmenting different areas, extracting main areas as shown in fig. 7, setting a region of interest (ROI) to follow, and facilitating rapid positioning of the next image.

And thirdly, extracting the point set of the main area in the second step, and performing rapid convex hull detection to obtain points of the outer layers of the point set, wherein the points of the adjacent three outer layers are connected to form a convex polyhedron as shown in fig. 8.

And fourthly, calculating the gravity centers of the point sets after cleaning in the first step, analyzing the workpiece material, adsorbing a layer of metal on the surfaces of the 5 areas separated in the first step, wherein the inside is made of uniform material, enabling the weight of the points of the 5 areas to be 1.02, enabling the weight of the points of the other areas to be 1, and obtaining the gravity center position Pg (6.10673,8.96545,1.00933) by taking the weight gravity centers into the weighted gravity center formulas (1), (2) and (3).

Step five, the center of gravity is projected to a convex hull surface, as shown in fig. 10, the center of gravity is projected along the gravity direction Vg (0, 1), the center of gravity is projected in a triangular surface, the vertexes of the triangular surface are respectively P1 (5.362,6.902,1.26), P2 (8.82, 13.328,1.264), P3 (5.082, 10.934,1.225), the plane determined by the triangular surface is shown in fig. 11, one point coordinate on the plane is P (5.362,6.902,1.26), and the normal vector is V (-0.0153096,0.00761611,0.999854).

Turning the point cloud and observing the supporting surface from the side view is shown in fig. 12, the left metal of the workpiece does not tilt corresponding to the area 3 in fig. 7, and the right metal tilting corresponds to the area 1 in fig. 7, and the turning corresponds to the real fig. 13.

And step six, measuring the distance of the gap according to the obtained supporting surface. Taking 9 points ROI on the area 1 and the area 3, calculating the distance from the coordinate mean point of each point ROI to the supporting surface, finally averaging to obtain the gap size, wherein the gap size of the area 1 is 0.0900554, the gap size of the area 3 is 0.00344432, and judging as NG.

Fig. 14, 15 and 16 are projection views, side views and true views of convex hulls of another workpiece, and the left and right metals are not warped, judged to be OK, and are consistent with the true views. After a number of tests, pairs such as shown in fig. 17 were performed with manual sorting.

Although terms of depth image, point set, connectivity segmentation, ROI following, etc. are used more in this application, the possibility of using other terms is not excluded. These terms are used merely for convenience in describing and explaining the nature of the invention; they are to be interpreted as any additional limitation that is not inconsistent with the spirit of the present invention.

According to the non-contact gap measurement method based on the convex hull and the gravity center projection, the three-dimensional data of the workpiece collected from the front is input, the near-real supporting surface is obtained by means of the convex hull and the gravity center projection, the size of the gap can be calculated finally, the method is rapid and accurate, the measured quality can be controlled accurately, and the method is beneficial to popularization and application in a large range.

Example two

Referring to fig. 18, fig. 18 is a schematic diagram of a functional module of a non-contact slit measurement system based on convex hull and gravity center projection according to a second embodiment of the present invention, where the system is suitable for executing the non-contact slit measurement method based on convex hull and gravity center projection according to the second embodiment of the present invention. The system specifically comprises the following modules:

the point set acquisition module 201 is configured to input a depth image, take out a point set, and perform preprocessing on the point set to obtain a preprocessed point set;

the region segmentation module 202 is configured to perform connectivity segmentation on the preprocessed point set, segment different regions, extract a main region, and set up an ROI to follow;

the convex hull detection module 203 is configured to extract a point set of a main area, and perform rapid convex hull detection to obtain points of outer layers of the point set, where the points of adjacent three outer layers are connected to form a convex polyhedron;

the gravity center calculating module 204 is configured to add weights to the point sets of different regions according to the preprocessed point sets, and calculate the gravity center according to the following weighted gravity center formula:

the supporting surface determining module 205 is configured to project the center of gravity along the gravity direction, and determine a supporting surface according to the positional relationship between the projection point and the convex hull surface;

the gap calculating module 206 is configured to select a point on the measured surface, calculate a distance between the point and the supporting surface, and obtain a gap.

Preferably, the point set acquisition module 201 is specifically configured to:

inputting a depth image and taking out a point set;

Preferably, the supporting surface determining module 205 is specifically configured to:

Preferably, the gap calculating module 206 is specifically configured to:

selecting a plurality of points on the measured surface;

According to the non-contact gap measurement system based on the convex hull and the gravity center projection, the three-dimensional data of the workpiece collected from the front is input, the near-real supporting surface is obtained by means of the convex hull and the gravity center projection, the size of the gap can be calculated finally, the gap measurement system is rapid and accurate, the measured quality can be controlled accurately, and the non-contact gap measurement system is beneficial to popularization and application in a large range.

The system can execute the method provided by any embodiment of the invention, and has the corresponding functional modules and beneficial effects of executing the method.

Example III

Fig. 19 is a schematic structural diagram of a computer device according to a third embodiment of the present invention. FIG. 19 illustrates a block diagram of an exemplary computer device 12 suitable for use in implementing embodiments of the present invention. The computer device 12 shown in fig. 19 is merely an example, and should not be construed as limiting the functionality and scope of use of embodiments of the present invention.

As shown in fig. 19, the computer device 12 is in the form of a general purpose computing device. Components of computer device 12 may include, but are not limited to: one or more processors or processing units 16, a system memory 28, a bus 18 that connects the various system components, including the system memory 28 and the processing units 16.

Bus 18 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor, and a local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, micro channel architecture (MAC) bus, enhanced ISA bus, video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus.

Computer device 12 typically includes a variety of computer system readable media. Such media can be any available media that is accessible by computer device 12 and includes both volatile and nonvolatile media, removable and non-removable media.

The system memory 28 may include computer system readable media in the form of volatile memory, such as Random Access Memory (RAM) 30 and/or cache memory 32. The computer device 12 may further include other removable/non-removable, volatile/nonvolatile computer system storage media. By way of example only, storage system 34 may be used to read from or write to non-removable, nonvolatile magnetic media (not shown in FIG. 19, commonly referred to as a "hard disk drive"). Although not shown in fig. 19, a magnetic disk drive for reading from and writing to a removable non-volatile magnetic disk (e.g., a "floppy disk"), and an optical disk drive for reading from or writing to a removable non-volatile optical disk (e.g., a CD-ROM, DVD-ROM, or other optical media) may be provided. In such cases, each drive may be coupled to bus 18 through one or more data medium interfaces. Memory 28 may include at least one program product having a set (e.g., at least one) of program modules configured to carry out the functions of embodiments of the invention.

A program/utility 40 having a set (at least one) of program modules 42 may be stored in, for example, memory 28, such program modules 42 including, but not limited to, an operating system, one or more application programs, other program modules, and program data, each or some combination of which may include an implementation of a network environment. Program modules 42 generally perform the functions and/or methods of the embodiments described herein.

The computer device 12 may also communicate with one or more external devices 14 (e.g., keyboard, pointing device, display 24, etc.), one or more devices that enable a user to interact with the computer device 12, and/or any devices (e.g., network card, modem, etc.) that enable the computer device 12 to communicate with one or more other computing devices. Such communication may occur through an input/output (I/O) interface 22. Moreover, computer device 12 may also communicate with one or more networks such as a Local Area Network (LAN), a Wide Area Network (WAN) and/or a public network, such as the Internet, through network adapter 20. As shown, network adapter 20 communicates with other modules of computer device 12 via bus 18. It should be appreciated that although not shown in fig. 19, other hardware and/or software modules may be used in connection with computer device 12, including, but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, data backup storage systems, and the like.

The processing unit 16 executes programs stored in the system memory 28 to perform various functional applications and data processing, for example, to implement the non-contact gap measurement method based on convex hull and center of gravity projection provided by the embodiment of the present invention.

Example IV

The fourth embodiment of the invention provides a computer readable storage medium, on which computer executable instructions are stored, which when executed by a processor, implement the non-contact gap measurement method based on convex hull and gravity center projection as provided by all the embodiments of the invention of the application.

Any combination of one or more computer readable media may be employed. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

The computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, either in baseband or as part of a carrier wave. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A computer readable signal medium may also be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

Computer program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, smalltalk, C ++ and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computer (for example, through the Internet using an Internet service provider).

In view of the foregoing, it will be evident to a person skilled in the art that the foregoing detailed disclosure may be presented by way of example only and may not be limiting. Although not explicitly described herein, those skilled in the art will appreciate that the present application is intended to embrace a variety of reasonable alterations, improvements and modifications to the embodiments. Such alterations, improvements, and modifications are intended to be proposed by this application, and are intended to be within the spirit and scope of the exemplary embodiments of this application.

Furthermore, certain terms in the present application have been used to describe embodiments of the present application. For example, "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. Thus, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various portions of this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined as suitable in one or more embodiments of the application.

It should be appreciated that in the foregoing description of embodiments of the present application, various features are grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the application. However, this is not to say that a combination of these features is necessary, and it is entirely possible for a person skilled in the art to extract some of them as separate embodiments to understand them at the time of reading this application. That is, embodiments in this application may also be understood as an integration of multiple secondary embodiments. While each secondary embodiment is satisfied by less than all of the features of a single foregoing disclosed embodiment.

Finally, it should be understood that the embodiments of the application disclosed herein are illustrative of the principles of the embodiments of the present application. Other modified embodiments are also within the scope of the present application. Accordingly, the embodiments disclosed herein are by way of example only and not limitation. Those skilled in the art can adopt alternative configurations to implement the applications herein according to embodiments herein. Accordingly, embodiments of the present application are not limited to the embodiments precisely described in the application.

Claims

1. A non-contact slit measurement method based on convex hull and gravity center projection, the method comprising:

2. The non-contact slit measurement method based on convex hull and gravity center projection according to claim 1, wherein the steps of inputting a depth image, taking out a point set, preprocessing the point set, and obtaining a preprocessed point set include:

inputting a depth image and taking out a point set;

3. The non-contact gap measurement method based on convex hull and gravity center projection according to claim 1, wherein the gravity center projection along the gravity direction, and the step of determining the supporting surface according to the positional relationship between the projection point and the convex hull surface comprises:

4. The non-contact gap measurement method based on convex hull and gravity center projection according to claim 1, wherein the step of selecting a point on the measured surface, calculating a distance from the point to the supporting surface, and obtaining the size of the gap comprises:

selecting a plurality of points on the measured surface;

5. A non-contact slit measurement system based on convex hull and center of gravity projection, the system comprising:

6. The non-contact gap measurement system based on convex hull and gravity center projection of claim 5, wherein the point set acquisition module is specifically configured to:

inputting a depth image and taking out a point set;

7. The non-contact gap measurement system based on convex hull and gravity center projection of claim 5, wherein the supporting surface determining module is specifically configured to:

8. The non-contact gap measurement system based on convex hull and gravity center projection of claim 5, wherein the gap calculation module is specifically configured to:

selecting a plurality of points on the measured surface;

9. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the convex hull and center of gravity projection based non-contact gap measurement method according to any of claims 1-4 when executing the computer program.

10. A storage medium containing computer executable instructions for execution by a computer processor to implement the convex hull and center of gravity projection based non-contact gap measurement method of any one of claims 1-4.