Measurement coverage prediction method of scanner and related equipment

Abstract

The invention relates to the technical field of scanners, and provides a measurement coverage prediction method of a scanner and related equipment. The method comprises the following steps: acquiring a plurality of scanning movement tracks of a target scanner and surface points of a to-be-scanned object, and determining a plurality of effective movement tracks from all the scanning movement tracks; for each effective movement track, acquiring a point movement track of the surface point relative to the target scanner according to the effective movement track, and calculating the length of the point movement track; obtaining the gap length between the laser rays of the target scanner, and calculating the distribution length of surface points according to the lengths of the motion trails of all the points and the gap length; and calculating the testability value of the surface area where the surface points are located according to the distribution length of the surface points. According to the method, the accuracy of measurement coverage prediction can be improved.

Description

Technical Field

[0001] The present application relates to the field of scanner technology, and in particular to a scanner measurement coverage prediction method and related equipment. Background Art

[0002] A scanner is an instrument that can acquire features (including contours, textures, colors, and stress) of a scanned object through contact or non-contact means. All scanners are specified with a nominal scanning range, which represents the spatial range of positions that can be measured by the scanner. This range can be two-dimensional, such as document scanners and line laser profilometers, or three-dimensional, such as lidar and computed tomography (CT). Depending on the measurement principle, some scanners can measure any position within the measurement range, while others can only measure a portion of the measurement range. For the latter, the nominal measurement range is actually the envelope of measurable positions. For example, the measurable positions of a multi-line structured light scanner are composed of multiple laser lines, and the nominal scanning range is the enclosing pyramid of the surfaces swept by these laser lines in space. For scanners that use the envelope of measurable positions as the measurement range, existing methods cannot accurately predict the area that can be measured after executing a given scanning trajectory based on the nominal measurement range, due to the presence of unmeasured gaps within the measurement range. The occurrence of measurement coverage prediction errors is mainly affected by three factors: the nominal measurement range of the scanner, the geometric characteristics of the scanned object, and the scanning trajectory.

[0003] Existing methods propose the conditions under which surface points are measured, called visibility conditions, which include the following three elements: In volume: The surface point is within the nominal measurement range of the scanner.

[0004] Unobstructed: The light from the laser projector to the surface point and from the surface point to the imaging element is not blocked.

[0005] Small off-axis: The angle between the scanner optical axis and the surface point normal vector is small enough.

[0006] The aforementioned visibility requirements demonstrate the ability of some scanner types to perform uniformly dense measurements within their measurement range. However, multi-line structured light 3D scanners lack the ability to determine whether a surface point is illuminated by a laser line. This results in the scanner executing a scan trajectory that satisfies visibility requirements, resulting in incomplete measurement coverage and, in other words, missed scans.

[0007] In some methods, for other scanners, the nominal measurement range is used, and additional limitations introduced by the measurement principle are added to construct the conditions for measurement determination to preliminarily determine the measurement coverage of the scanner. Due to the existence of gaps, these conditions cannot reliably predict the area that can be measured after the scanner executes a given scanning trajectory, resulting in the problem of incorrect prediction of measurement coverage. Summary of the Invention

[0008] This application provides a method for predicting the measurement coverage of a scanner and related devices, which can solve the problem of incorrect prediction of the measurement coverage of a scanner with gaps in the measurement range.

[0009] In a first aspect, this application provides a method for predicting the measurement coverage of a scanner. The method for predicting the measurement coverage includes: Obtain multiple scanning movement trajectories of a target scanner and surface points of an object to be scanned, and determine multiple effective movement trajectories from all the scanning movement trajectories; an effective movement trajectory is a scanning movement trajectory that satisfies the measurement determination conditions when using the target scanner to scan and measure the surface points. For each effective movement trajectory, obtain the point movement trajectory of the surface points relative to the target scanner according to the effective movement trajectory, and calculate the length of the point movement trajectory; the point movement trajectory is the movement trajectory of the surface points relative to the target scanner when the target scanner is regarded as stationary. Obtain the gap length between the laser lines of the target scanner, and calculate the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length; the distribution length is used to describe the probability that the surface points are scanned and measured. Calculate the measurability value of the surface area where the surface points are located according to the distribution length of the surface points; the measurability value is used to describe the probability that the surface area is completely measured by the target scanner.

[0010] Optionally, the measurement determination conditions are: The surface points are located within the nominal measurement range corresponding to the scanning movement trajectory of the target scanner, and the target scanner satisfies the constraint conditions caused by the measurement principle when moving along the scanning movement trajectory.

[0011] Optionally, calculating the length of the point movement trajectory includes: Select a target calculation method from a first calculation method, a second calculation method, and a third calculation method; Calculate the length of the point movement trajectory according to the target calculation method.

[0012] Optionally, the first calculation method is: Use the length of the major axis of the bounding box of the point movement trajectory as the length of the point movement trajectory; The second calculation method is: The modulus length of the vector from the starting point to the ending point of the point movement trajectory is used as the length of the point movement trajectory; The third calculation method is as follows: The arc length of the point movement trajectory is used as the length of the point movement trajectory.

[0013] Optionally, calculating the distribution length of surface points according to the lengths of all point movement trajectories and the gap length, including: For each point movement trajectory, determine whether the length of the point movement trajectory is greater than or equal to the gap length. If so, regard the point movement trajectory as a measurable movement trajectory; Calculate the distribution length of surface points according to the lengths of all measurable movement trajectories.

[0014] Optionally, calculating the distribution length of surface points according to the lengths of all measurable movement trajectories, including: Through the formula: ; Calculate the distribution length of surface points ; Wherein, represents the effective movement trajectory corresponding to the measurable movement trajectory, represents the set of effective movement trajectories corresponding to all measurable movement trajectories, represents the length of the corresponding measurable movement trajectory, is the surface point in the surface area, represents all scanning movement trajectories.

[0015] Optionally, calculating the measurability value of the surface area where the surface points are located according to the distribution length of the surface points, including: Through the formula: ; Calculate the measurability value of the surface area ; Wherein, represents the set of all surface points in the surface area, represents the preset length of the point movement trajectory required for measurability when scanning and measuring the surface point

[0016] In a second aspect, the present application provides a measurement coverage prediction device for a scanner, including: A determination module, configured to obtain multiple scanning movement trajectories of a target scanner and surface points of an object to be scanned, and determine multiple effective movement trajectories from all the scanning movement trajectories; an effective movement trajectory is a scanning movement trajectory that satisfies a measurement determination condition when using the target scanner to scan and measure the surface points; ​The first calculation module is configured to, for each valid movement trajectory, obtain the point movement trajectory of the surface point relative to the target scanner according to the valid movement trajectory, and calculate the length of the point movement trajectory; the point movement trajectory is the movement trajectory of the surface point relative to the target scanner when the target scanner is stationary. The acquisition module is configured to obtain the gap length between the laser lines of the target scanner, and calculate the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length; the distribution length is used to describe the probability that the surface points are scanned and measured. The second calculation module is configured to calculate the measurability value of the surface area where the surface points are located according to the distribution length of the surface points; the measurability value is used to describe the probability that the surface area is completely measured by the target scanner.

[0017] In a third aspect, an embodiment of the present application provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned measurement coverage prediction method of the scanner is implemented.

[0018] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the above-mentioned measurement coverage prediction method of the scanner is implemented.

[0019] The above solution of the present application has the following beneficial effects: In some embodiments of the present application, by obtaining a plurality of scanning movement trajectories of the target scanner and the surface points of the object to be scanned, a plurality of valid movement trajectories are determined from all the scanning movement trajectories when using the target scanner to scan and measure the surface points. Then, for each valid movement trajectory, the point movement trajectory of the surface point relative to the target scanner is obtained according to the valid movement trajectory, and the length of the point movement trajectory is calculated. Next, the gap length between the laser lines of the scanner is obtained, and the distribution length of the surface points is calculated according to the lengths of all the point movement trajectories and the gap length. Finally, the measurability value of the surface area where the surface points are located is calculated according to the distribution length of the surface points. Among them, defining the distribution length can quantify the probability of the surface points being measured and covered, provide an accurate description of the measured status of the surface points, considering the gap length between the laser lines when calculating the distribution length can improve the accuracy of the distribution length, and calculating the measurability value of the surface area according to the distribution length can effectively improve the prediction accuracy of the surface area being measured and covered when using a scanner with gaps in the measurement range.

[0020] Other beneficial effects of the present application will be described in detail in the subsequent specific implementation part. Description of the Drawings

[0021] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 Flowchart of the measurement coverage prediction method for the scanner provided by an embodiment of the present application; Figure 2 Schematic structural diagram of the multi-line structured light three-dimensional scanner provided by an embodiment of the present application; Figure 3 Schematic plane projection diagram provided by an embodiment of the present application; Figure 4 Schematic diagram of the projection result provided by an embodiment of the present application; Figure 5 Schematic diagram of the point movement trajectory provided by an embodiment of the present application; Figure 6 Schematic structural diagram of the measurement coverage prediction device for the scanner provided by an embodiment of the present application; Figure 7 Schematic structural diagram of the terminal device provided by an embodiment of the present application. Detailed implementation manners

[0023] In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are proposed to thoroughly understand the embodiments of the present application. However, those skilled in the art should clearly understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid unnecessary details from interfering with the description of the present application.

[0024] It should be understood that when used in the specification and appended claims of the present application, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0025] It should also be understood that the term " / and / or" used in the specification and appended claims of the present application refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0026] As used in the specification of this application and the appended claims, the term "if" may be construed contextually as "when" or "once" or "in response to determining" or "in response to detecting". Similarly, the phrase "if determined" or "if [the described condition or event] is detected" may be construed contextually to mean "once determined" or "in response to determining" or "once [the described condition or event] is detected" or "in response to detecting [the described condition or event]".

[0027] In addition, in the description of the specification of this application and the appended claims, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0028] Reference to "one embodiment" or "some embodiments" or the like described in the specification of this application means that a specific feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of this application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments" and the like that appear in different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "comprising", "including", "having" and their variants all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0029] Aiming at the problem of prediction error of measurement coverage of a scanner with gaps in the existing measurement range, the embodiments of this application provide a method for predicting the measurement coverage of a scanner. The method for predicting the measurement coverage obtains multiple scanning movement trajectories of a target scanner and surface points of an object to be scanned, determines multiple effective movement trajectories from all the scanning movement trajectories when using the target scanner to scan and measure the surface points, then for each effective movement trajectory, obtains the point movement trajectory of the surface points relative to the target scanner according to the effective movement trajectory and calculates the length of the point movement trajectory, then obtains the gap length between the laser lines of the scanner, and calculates the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length, and finally calculates the measurability value of the surface area where the surface points are located according to the distribution length of the surface points. Among them, defining the distribution length can quantify the probability of the surface points being measured and covered, provide an accurate description of the measured condition of the surface points, considering the gap length between the laser lines when calculating the distribution length can improve the accuracy of the distribution length, and calculating the measurability value of the surface area according to the distribution length can effectively improve the prediction accuracy of the surface area being measured and covered when using a scanner with gaps in the measurement range for measurement.

[0030] Next, an exemplary description will be given of the measurement coverage prediction method for the scanner provided in this application.

[0031] As Figure 1 shown, the measurement coverage prediction method for the scanner provided in this application includes the following steps: Step 11: Obtain multiple scanning movement trajectories of the target scanner and the surface points of the object to be scanned, and determine multiple effective movement trajectories from all the scanning movement trajectories.

[0032] The above-mentioned target scanner is a laser line scanner, which has gaps between laser lines during scanning. The object to be scanned is an object that needs to be scanned and measured, such as a document to be scanned, an obstacle to be scanned, etc. The surface point is any point in the surface area of the object to be scanned that needs to be scanned and measured. The scanning movement trajectory is the movement trajectory of the target scanner during scanning. The above-mentioned effective movement trajectory is the scanning movement trajectory that satisfies the measurement determination condition when using the target scanner to scan and measure the surface points.

[0033] In some embodiments of this application, multiple scanning movement trajectories can be obtained by recording the movement trajectories of the target scanner during historical operation (such as the movement trajectories of the target scanner when scanning and measuring other objects at historical moments) and segmenting them. The above-mentioned measurement determination condition is: The surface point is located within the nominal measurement range corresponding to the scanning movement trajectory of the target scanner, and the target scanner satisfies the constraint conditions caused by the measurement principle (such as the angle between the optical axis of the scanner and the normal vector of the surface point is less than a preset angle) when moving along the scanning movement trajectory.

[0034] It should be noted that the nominal measurement range corresponding to the scanning movement trajectory refers to the range that can be measured when the target scanner scans and measures along this scanning movement trajectory. If the number of effective movement trajectories is 0, it is directly considered that the surface point will be missed by the target scanner.

[0035] Exemplarily, for a multi-line structured light 3D scanner as Figure 2 shown, Figure 2 the rectangle in it is the projector, the dashed trapezoid is the measurement volume, cameras A and B are provided at both ends of the projector. The projector emits projection light to the surface point The reflected light A of the surface point enters camera A, and the reflected light B enters camera B. The dashed line between the projector and the measurement volume is the optical axis, and the solid-line quadrilateral is the scanning plane , is the normal vector of the surface point , is the angle between the optical axis and . For the multi-line structured light 3D scanner as Figure 2 shown, the above-mentioned measurement determination condition is expressed as: ; Among them, represents the position and orientation of the target scanner, represents the set of all positions and orientations in the scanning movement trajectory, represents a surface point, represents the set of all surface points within the nominal measurement range corresponding to the scanning movement trajectory, represents the projected light vector, represents the first reflected light vector (such as Figure 2 the vector of reflected light A in ), represents the second reflected light vector (such as Figure 2 the vector of reflected light B in ), represents the angle between the optical axis and ), represents the maximum at which the surface point ( when the intensity of the reflected light will be insufficient to be detected by the scanner).

[0036] Step 12: For each effective movement trajectory, obtain the point movement trajectory of the surface point relative to the target scanner according to the effective movement trajectory, and calculate the length of the point movement trajectory.

[0037] The point movement trajectory is the movement trajectory of the surface point relative to the target scanner when the target scanner is stationary.

[0038] In some embodiments of the present application, according to the relative position between the surface point and the target scanner when the object to be scanned is waiting to be scanned, the target scanner can be used as a stationary reference object. When the target scanner moves according to the effective movement trajectory, according to the physical principle of relative motion, the point movement trajectory corresponding to the effective movement trajectory can be obtained. The steps of calculating the length of the point movement trajectory include: The first step is to select a target calculation method from the first calculation method, the second calculation method, and the third calculation method.

[0039] Specifically, the first calculation method is: Taking the length of the major axis of the bounding box of the point movement trajectory as the length of the point movement trajectory.

[0040] The second calculation method is: Taking the modulus length of the vector from the starting point to the ending point of the point movement trajectory as the length of the point movement trajectory.

[0041] The third calculation method is: Taking the arc length of the point movement trajectory as the length of the point movement trajectory.

[0042] Exemplarily, the target calculation method can be selected according to the actual shape of the point movement trajectory. For example, for a point movement trajectory with a straight line shape, the second calculation method can be selected to calculate its length; for a point movement trajectory with an arc shape, the third calculation method can be selected to calculate its length; for a point movement trajectory with an irregular curve shape, the first calculation method can be selected to calculate its length.

[0043] In the second step, calculate the length of the point movement trajectory according to the target calculation method.

[0044] Taking a multi-line structured scanner as an example, the measurable positions in its nominal scanning range are composed of the scanning surfaces swept by several laser lines; the gap is a quadrangular pyramid between the scanning surfaces, having an infinite size in the radial direction (the direction close to or away from the laser emitter) and a finite size in the direction perpendicular to the radial direction. Therefore, for this special case of the multi-line structured scanner, it can be reduced to be processed by projecting onto a two-dimensional plane: As Figure 3 shown, in the scanner coordinate system , project the surface point, multiple scanning surfaces and the point movement trajectory , onto the plane, is the horizontal axis of this plane, is the vertical axis of this plane, to obtain the projection point and the projection line , as well as the projected point movement trajectory .

[0045] The specific projection result is as Figure 4 shown. The regularly arranged solid lines are the projection lines , the dotted lines are the major axes of the rhombus formed by the projection lines , and its length is the gap length . The curve with an arrow is the projected point movement trajectory , and its length is .

[0046] Step 13, obtain the gap length between the laser lines of the target scanner, and calculate the distribution length of the surface points according to the lengths of all point movement trajectories and the gap length.

[0047] The above distribution length is used to describe the probability that the surface points are scanned and measured. The above laser lines are the scanning lines when the target scanner performs scanning and measurement.

[0048] In some embodiments of the present application, tools such as rangefinders can be used to obtain the gap length between the laser lines. The step of calculating the distribution length of the surface points according to the lengths of all point movement trajectories and the gap length is specifically as follows: In the first step, for each point motion trajectory, determine whether the length of the point motion trajectory is greater than or equal to the gap length. If so, regard the point motion trajectory as a measurable motion trajectory.

[0049] That is, a measurable motion trajectory is a point motion trajectory that satisfies the condition that the length of the point motion trajectory is greater than or equal to the gap length.

[0050] In the second step, calculate the distribution length of the surface points according to the lengths of all measurable motion trajectories.

[0051] Through the formula: ; Calculate the distribution length of the surface points .

[0052] Among them, represents the effective movement trajectory corresponding to the measurable motion trajectory, represents the set of effective movement trajectories corresponding to all measurable motion trajectories, represents the length of the corresponding measurable motion trajectory, is the surface point in the surface area, represents all scanning movement trajectories.

[0053] It should be noted that if there is a measurable motion trajectory with a length greater than the gap length, the effective trajectory corresponding to this measurable motion trajectory must intersect with the edge of the gap and also with the surface points, that is, the surface points can be measured, which is expressed as: ; Among them, represents the position and attitude of the target scanner, represents the set of all positions and attitudes in the scanning movement trajectory, represents the surface point, represents the set of points that can be measured within the nominal measurement range corresponding to the scanning movement trajectory, represents the gap edge, represents the gap length.

[0054] Step 14, calculate the measurability value of the surface area where the surface points are located according to the distribution length of the surface points.

[0055] The above measurability value is used to describe the probability that the surface area is completely measured by the target scanner. The above surface area is the area that needs to be scanned and measured for the object to be scanned. For example, for a document, the surface area is the part of the document that needs to be scanned and measured (such as the part of the document with actual text or images).

[0056] Specifically, through the formula: ; Calculate the measurability value of the surface area .

[0057] Among them, represents the set of all surface points in the surface area, represents the preset length of the point movement trajectory required for measurability when scanning and measuring the surface point .

[0058] Exemplarily, the above preset length is set according to the positions of different surface points and can be set to the gap length between the laser lines of the target scanner. As Figure 5 shown, taking the point movement trajectories and of two surface points as an example, Figure 5 the solid curve with arrows in is , the dotted curve with arrows is , the solid line is the projection line . When is close to the projection line, even if it is significantly shorter than , it still has a high probability of passing through the projection line; on the contrary, located at the center of the gap requires a longer length to pass through the projection line at the edge of the gap. It can be seen that the effective trajectory lengths required for measurability of points at different positions within the surface area are different. .

[0059] It should be noted that after calculating the measurability value of the surface area, it is possible to state whether the surface area can be completely measured by the target scanner based on the measurability value, and it is possible to determine which surface points have a low probability of being measured and covered according to the distribution length of each surface point, facilitating the adjustment of the position and posture of the object to be scanned or the movement trajectory of the scanner to reduce the situation of missed scanning by the target scanner.

[0060] It is worth mentioning that defining the distribution length can quantify the probability of a surface point being measured and covered, provide an accurate description of the measured situation of the surface point. Considering the gap length between the laser lines when calculating the distribution length can improve the accuracy of the distribution length, and calculating the measurability value of the surface area according to the distribution length can effectively improve the prediction accuracy of the surface area being measured and covered.

[0061] The following is an exemplary description of the measurement coverage prediction device of the scanner provided in this application.

[0062] As Figure 6As shown in the figure, an embodiment of the present application provides a measurement coverage prediction device for a scanner. The measurement coverage prediction device 600 of the scanner includes: A determination module 601, configured to obtain a plurality of scanning movement trajectories of a target scanner and surface points of an object to be scanned, and determine a plurality of effective movement trajectories from all the scanning movement trajectories; an effective movement trajectory is a scanning movement trajectory that satisfies a measurement determination condition when the target scanner scans and measures the surface points. A first calculation module 602, configured to respectively for each effective movement trajectory, obtain a point movement trajectory of the surface points relative to the target scanner according to the effective movement trajectory, and calculate the length of the point movement trajectory; the point movement trajectory is the movement trajectory of the surface points relative to the target scanner when the target scanner is regarded as stationary. An acquisition module 603, configured to obtain the gap length between the laser lines of the target scanner, and calculate the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length; the distribution length is used to describe the probability that the surface points are scanned and measured. A second calculation module 604, configured to calculate the measurability value of the surface area where the surface points are located according to the distribution length of the surface points; the measurability value is used to describe the probability that the surface area is completely measured by the target scanner.

[0063] It should be noted that for the information interaction, execution process, etc. between the above-mentioned devices / units, since they are based on the same concept as the method embodiment of the present application, their specific functions and the technical effects brought thereby can be specifically referred to the method embodiment part, and will not be elaborated here.

[0064] Those skilled in the art can clearly understand that for the convenience and conciseness of description, only the above-mentioned division of each functional unit and module is used as an example for illustration. In practical applications, the above-mentioned functions can be allocated to different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of each functional unit and module are only for the convenience of mutual distinction and do not limit the protection scope of the present application. The specific working processes of the units and modules in the above-mentioned system can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated here.

[0065] As Figure 7 shown, an embodiment of the present application provides a terminal device. The terminal device D10 of this embodiment includes: at least one processor D100 ( Figure 7only shows one processor), a memory D101, and a computer program D102 stored in the memory D101 and executable on the at least one processor D100. When the processor D100 executes the computer program D102, the steps in any of the above method embodiments are implemented.

[0066] Specifically, when the processor D100 executes the computer program D102, by obtaining multiple scanning movement trajectories of a target scanner and surface points of an object to be scanned, determining multiple effective movement trajectories from all the scanning movement trajectories for scanning and measuring the surface points using the target scanner, then for each effective movement trajectory, obtaining the point movement trajectory of the surface points relative to the target scanner according to the effective movement trajectory, calculating the length of the point movement trajectory, obtaining the gap length between the laser lines of the scanner, calculating the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length, and finally calculating the measurability value of the surface area where the surface points are located according to the distribution length of the surface points. Among them, defining the distribution length can quantify the probability of the surface points being measured and covered, provide an accurate description of the measured condition of the surface points. Considering the gap length between the laser lines when calculating the distribution length can improve the accuracy of the distribution length. Calculating the measurability value of the surface area according to the distribution length can effectively improve the prediction accuracy of the surface area being measured and covered when using a scanner with gaps in the measurement range for measurement.

[0067] The so-called processor D100 may be a central processing unit (CPU, Central Processing Unit), and this processor D100 may also be other general-purpose processors, digital signal processors (DSP, Digital Signal Processor), application specific integrated circuits (ASIC, Application Specific Integrated Circuit), field-programmable gate arrays (FPGA, Field-Programmable Gate Array), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or this processor may also be any conventional processor, etc.

[0068] In some embodiments, the memory D101 may be an internal storage unit of the terminal device D10, such as a hard disk or memory of the terminal device D10. In other embodiments, the memory D101 may also be an external storage device of the terminal device D10, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc., equipped on the terminal device D10. Further, the memory D101 may also include both the internal storage unit and the external storage device of the terminal device D10. The memory D101 is used to store an operating system, application programs, a boot loader (BootLoader), data, and other programs, such as program codes of the computer program. The memory D101 may also be used to temporarily store data that has been output or is to be output.

[0069] An embodiment of the present application also provides a computer-readable storage medium storing a computer program, which when executed by a processor, can implement the steps in the above-mentioned method embodiments.

[0070] An embodiment of the present application provides a computer program product, which when running on a terminal device, enables the terminal device to execute the steps in the above-mentioned method embodiments.

[0071] If the 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. Based on this understanding, to implement all or part of the processes in the above-mentioned method embodiments of the present application, a computer program can be used to instruct relevant hardware to complete. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, an executable file, or some intermediate form, etc. The computer-readable medium may at least include: any entity or device that can carry the computer program code to the measurement coverage prediction method device / terminal device of the scanner, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium. Such as a USB flash drive, a mobile hard disk, a magnetic disk, or an optical disc, etc.

[0072] In the above embodiments, the descriptions of the respective embodiments each have their own emphasis. For parts not described in detail or recorded in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0073] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professionals can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of this application.

[0074] The above is the preferred implementation manner of this application. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle described in this application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of this application.

Claims

1. A measurement coverage prediction method for a scanner, characterized in that, Including: Obtain multiple scanning movement trajectories of a target scanner and surface points of an object to be scanned, and determine multiple valid movement trajectories from all the scanning movement trajectories; The valid movement trajectory is a scanning movement trajectory that satisfies the measurement determination condition when the target scanner scans and measures the surface points; For each of the valid movement trajectories, obtain the point movement trajectory of the surface points relative to the target scanner according to the valid movement trajectory, and calculate the length of the point movement trajectory; The point movement trajectory is the movement trajectory of the surface points relative to the target scanner when the target scanner is regarded as stationary; Obtain the gap length between the laser lines of the target scanner, and calculate the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length; the distribution length is used to describe the probability that the surface points are scanned and measured; Calculate the measurability value of the surface area where the surface points are located according to the distribution length of the surface points; the measurability value is used to describe the probability that the surface area is completely measured by the target scanner.

2. The measurement coverage prediction method according to claim 1, wherein The measurement determination condition is: The surface points are located within the nominal measurement range corresponding to the scanning movement trajectory of the target scanner, and the target scanner satisfies the constraint conditions caused by the measurement principle when moving along the scanning movement trajectory.

3. The measurement coverage prediction method according to claim 1, characterized in that, The calculating the length of the point movement trajectory includes: Select a target calculation method from a first calculation method, a second calculation method, and a third calculation method; Calculate the length of the point movement trajectory according to the target calculation method.

4. The measurement coverage prediction method according to claim 3, wherein The first calculation method is: Take the length of the major axis of the bounding box of the point movement trajectory as the length of the point movement trajectory; The second calculation method is: Take the modulus length of the vector from the starting point to the ending point of the point movement trajectory as the length of the point movement trajectory; The third calculation method is: Take the arc length of the point movement trajectory as the length of the point movement trajectory.

5. The measurement coverage prediction method according to claim 1, wherein The calculating the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length includes: For each of the point movement trajectories, determine whether the length of the point movement trajectory is greater than or equal to the gap length. If so, regard the point movement trajectory as a measurable movement trajectory; Calculate the distribution length of the surface points according to the lengths of all the measurable movement trajectories.

6. The measurement coverage prediction method according to claim 5, characterized in that, The calculating the distribution length of the surface points according to the lengths of all the measurable movement trajectories includes: Through the formula: Calculate the distribution length of the surface points ; Among them, represents the effective movement trajectory corresponding to the measurable movement trajectory, represents the set of effective movement trajectories corresponding to all measurable movement trajectories, represents the length of the measurable movement trajectory corresponding to, is the surface point, represents all scanning movement trajectories.

7. The measurement coverage prediction method according to claim 6, wherein The calculating the measurability value of the surface area where the surface points are located according to the distribution length of the surface points includes: Through the formula: Calculate the measurability value of the surface area ; Among them, represents the set of all surface points in the surface area, represents the preset length of the point motion trajectory required for measurability when performing scanning measurement on the surface points.

8. A measurement coverage prediction device for a scanner, characterized in that, Including: A determination module, configured to obtain multiple scanning movement trajectories of a target scanner and surface points of an object to be scanned, and determine multiple valid movement trajectories from all the scanning movement trajectories; The valid movement trajectory is a scanning movement trajectory that satisfies the measurement determination condition when the target scanner scans and measures the surface points; A first calculation module, configured to, for each of the valid movement trajectories, obtain the point movement trajectory of the surface points relative to the target scanner according to the valid movement trajectory, and calculate the length of the point movement trajectory; The trajectory of the point movement is the trajectory of the surface point relative to the target scanner when the target scanner is regarded as stationary. An acquisition module is configured to acquire the gap length between the laser lines of the target scanner, and calculate the distribution length of the surface points according to the lengths of all the point movement trajectories and the gap length; the distribution length is used to describe the probability that the surface points are scanned and measured. A second calculation module is configured to calculate the measurability value of the surface area where the surface points are located according to the distribution length of the surface points; the measurability value is used to describe the probability that the surface area is completely measured by the target scanner.

9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, the measurement coverage prediction method of the scanner according to any one of claims 1 to 7 is implemented.

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

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