Handheld measurement device and measurement system

Abstract

The application provides a handheld measuring device and a measuring system, and belongs to the technical field of measuring devices.The handheld measuring device comprises a bearing frame, a handle, a linear laser and a plurality of calibration point structures.The bearing frame is an annular frame body arranged in axial symmetry.The inner annular surface of the bearing frame forms a laser light outlet.The upper surface of the bearing frame is alternately provided with a plurality of calibration planes along the circumferential direction of the bearing frame.The adjacent two calibration planes are distributed in a staggered manner upwards and downwards.Each calibration plane is perpendicular to the upward and downward directions.The handle is arranged on the bearing frame.The linear laser is arranged in the bearing frame.The light emitting direction of the linear laser is inclined downward.The light emitting surface of the linear laser is opposite to the laser light outlet.The orthogonal projection of the light plane emitted by the linear laser on the plane perpendicular to the upward and downward directions overlaps with the symmetry axis of the bearing frame.The plurality of calibration point structures are arranged on the plurality of calibration planes.The handheld measuring device of the application does not need to be photographed by a plurality of cameras, and the accuracy of measurement is improved.

Description

Technical Field

[0001] This invention belongs to the field of measurement equipment technology, specifically relating to a handheld measuring device and measurement system. Background Technology

[0002] Rapid societal development has led to increasingly demanding measurement requirements. While traditional coordinate measuring machines (CMMs) can perform high-precision measurements, they suffer from several efficiency issues. For example, their large size necessitates specific installation locations, and variations in measurement results can occur due to different operators. To address these problems, portable handheld measuring devices have emerged, achieving both high-precision and easy measurement.

[0003] Portable handheld measuring devices are equipped with spatial recognition technology that enables high-precision 3D measurement, and have low operator requirements. However, existing portable handheld measuring devices generally use multi-camera calibration and transformation. During measurement, inaccurate calculation of the spatial coordinate transformation matrix H between different camera coordinate systems can lead to reduced measurement accuracy and insufficient reliability. Summary of the Invention

[0004] This invention provides a handheld measuring device and system, aiming to solve the problem in the prior art where calibration transformation using multiple cameras leads to reduced measurement accuracy and insufficient reliability due to inaccurate calculation of the spatial coordinate transformation matrix H between different camera coordinate systems.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, a handheld measuring device is provided, comprising:

[0007] The support frame is an axially symmetrical ring-shaped frame. The inner ring surface of the support frame forms a laser light outlet. The upper surface of the support frame is provided with multiple calibration planes alternately along the circumference of the support frame. Adjacent calibration planes are staggered vertically, and each calibration plane is perpendicular to the vertical direction.

[0008] A handle is provided on the support frame;

[0009] A linear laser is disposed within the support frame. The laser's emission direction is tilted downwards, and its emission surface faces the laser emission port. On a plane perpendicular to the vertical direction, the orthographic projection of the plane emitted by the linear laser overlaps with the axis of symmetry of the support frame.

[0010] Multiple calibration point structures are respectively set on multiple calibration planes.

[0011] In conjunction with the first aspect, in one possible implementation, there are two handles, which are symmetrically distributed on opposite sides of the support frame with the axis of symmetry of the support frame as the axis.

[0012] In conjunction with the first aspect, in one possible implementation, the arrangement of the calibration point structures on two adjacent calibration planes is different.

[0013] In conjunction with the first aspect, in one possible implementation, a first mounting hole is formed in the support frame, which is gradually inclined downward from the inside to the outside, and the inner end face of the first mounting hole forms the laser light outlet;

[0014] The linear laser is inserted into the first mounting hole, and an elastic fixing structure is provided at the laser output port. The elastic fixing structure is configured with a pre-tightening force to move the linear laser away from the laser output port.

[0015] In some embodiments, a limiting hole perpendicular to the first mounting hole is formed on the side wall near the laser emission port, and the elastic fixing structure includes:

[0016] The limiting block has a first limiting surface that conforms to and limits the light-emitting surface of the linear laser, and a second limiting surface that conforms to and limits the outer peripheral surface of the linear laser; and

[0017] An elastic element is disposed within the limiting hole and connected to the limiting block. The elastic element is configured with a preload force that causes the limiting block to move toward the central axis of the first mounting hole.

[0018] In conjunction with the first aspect, in one possible implementation, a downwardly opening second mounting hole is formed on the calibration plane, and the calibration point structure includes:

[0019] The light source is located inside the second mounting hole;

[0020] A light guide post is positioned above the light source, and both its outer peripheral surface and upper surface are covered with a mask plate; and

[0021] A lens is placed on the upper part of the light guide post.

[0022] In conjunction with the first aspect, in one possible implementation, the angle between the light output direction of the linear laser and the vertical direction is 20° to 40°.

[0023] In conjunction with the first aspect, in one possible implementation, the support frame also forms a battery mounting space with an opening on one side, the battery mounting space contains a battery, the opening side of the battery mounting space has a removable cover with a sealing cap, and the plurality of calibration point structures are electrically connected to the battery respectively.

[0024] The solution described in this application, compared with the prior art, employs a line structured light measurement model. A linear laser emitted by a linear laser intersects the surface of the object being measured, forming a light stripe at the intersection. Simultaneously, due to the staggered distribution of calibration planes, the calibration points formed by the calibration point structure can establish specific sequencing information under different postures, thereby revealing the real-time posture information of the handheld measuring device. Furthermore, because the support frame is a ring structure with a central opening, a single camera above the handheld measuring device can simultaneously acquire both the posture information and the light stripe information. The three-dimensional posture information compensates for the missing dimensional information in the light stripe, ultimately establishing a three-dimensional representation of the object's surface. Using the handheld measuring device of this application eliminates the need for multiple cameras, avoiding the problems of reduced measurement accuracy and insufficient reliability caused by multi-camera calibration conversion, thus improving measurement accuracy.

[0025] Secondly, embodiments of the present invention also provide a measurement system, comprising:

[0026] The worktable is used to support the object being measured.

[0027] A measuring frame is placed on the worktable, and a measuring space is formed within the measuring frame to accommodate the object to be measured.

[0028] A camera device is mounted on top of the measuring frame, with the camera of the camera device positioned vertically downwards; and

[0029] The aforementioned handheld measuring device.

[0030] In conjunction with the second aspect, in one possible implementation, the top of the measuring frame is provided with a mounting bracket, the mounting bracket forming a contact plane parallel to the vertical direction, the camera device is in contact with the contact plane, and the camera device and the mounting bracket are fixedly connected by at least two fasteners.

[0031] Compared with the prior art, the solution shown in this application uses a handheld measuring device. During use, the handheld measuring device is positioned between the object being measured and the camera device. A single camera device can simultaneously acquire the posture information and light stripe information of the handheld measuring device. The three-dimensional posture information is used to compensate for the missing dimensional information of the light stripe, and finally, three-dimensional information of the surface of the object being measured can be established. This eliminates the need for multiple cameras to take pictures, avoids the problem of reduced measurement accuracy and insufficient reliability caused by calibration conversion of multiple cameras, and improves the accuracy of measurement. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the measurement system provided in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the structure of a handheld measuring device provided in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the calibration point structure used in an embodiment of the present invention;

[0035] Figure 4 This is a cross-sectional view of the internal structure of a handheld measuring device provided in an embodiment of the present invention;

[0036] Figure 5 for Figure 4 Enlarged view of part A;

[0037] Figure 6 This is a cross-sectional view of the assembly structure of the battery, cover, and support frame used in an embodiment of the present invention;

[0038] Figure 7 This is a schematic diagram of the assembly of the measuring frame and the camera equipment used in an embodiment of the present invention;

[0039] Figure 8 This is a usage diagram of the measurement system provided in an embodiment of the present invention, wherein the outline below the handheld measuring device is the outline of the laser light plane.

[0040] Explanation of reference numerals in the attached figures:

[0041] 100. Handheld measuring devices;

[0042] 110. Support frame; 111. Calibration plane; 112. Limiting hole;

[0043] 120. Handle;

[0044] 130. Linear laser;

[0045] 140. Calibration point structure; 141. Light source; 142. Light guide column; 143. Lens; 144. Mask;

[0046] 150. Elastic fixing structure; 151. Limiting block; 152. Elastic component;

[0047] 160. Battery;

[0048] 170. Capping;

[0049] 200. Camera equipment;

[0050] 300. Measurement frame;

[0051] 400. Workbench;

[0052] 500. The object being tested;

[0053] 600. Mounting bracket; 610. First mounting plate; 620. Second mounting plate; 630. Reinforcing rib plate. Detailed Implementation

[0054] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0055] Unless otherwise expressly defined, the use of terms such as "first," "second," or "third" in the claims, description, and accompanying drawings of this invention is for distinguishing different objects and not for describing a specific order.

[0056] Unless otherwise expressly defined, in the claims, description, and accompanying drawings of this invention, the use of directional terms such as "center," "lateral," "longitudinal," "horizontal," "vertical," "top," "bottom," "inner," "outer," "upper," "lower," "front," "rear," "left," "right," "clockwise," "counterclockwise," "high," and "low" to indicate orientation or positional relationships is based on the orientation and positional relationships shown in the accompanying drawings and is only for the convenience of describing the invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the specific scope of protection of this invention.

[0057] Unless otherwise expressly defined, the terms "fixed connection" or "fixed connection" used in the claims, description and drawings of this invention should be interpreted broadly to refer to any connection in which there is no displacement or relative rotation relationship between the two parties, including non-removable fixed connection, detachable fixed connection, integral connection and fixed connection by other means or components.

[0058] In the claims, description and accompanying drawings of this invention, the terms "comprising," "having," and variations thereof are used to mean "including but not limited to."

[0059] Please refer to the following: Figures 1 to 8 The handheld measuring device provided by the present invention will now be described. The handheld measuring device 100 includes a support frame 110, a handle 120, a linear laser 130, and multiple calibration point structures 140. The support frame 110 is an axially symmetrical ring frame, with the inner ring surface of the support frame 110 forming a laser emission port. Multiple calibration planes 111 are alternately arranged along the circumference of the support frame on the upper surface of the support frame 110, with adjacent calibration planes 111 staggered vertically. Each calibration plane 111 is perpendicular to the vertical direction. The handle 120 is located on the support frame 110. The linear laser 130 is located inside the support frame 110, with the emission direction of the linear laser 130 tilted downwards. The emission surface of the linear laser 130 faces the laser emission port. On a plane perpendicular to the vertical direction, the orthographic projection of the light plane emitted by the linear laser 130 overlaps with the axis of symmetry of the support frame 110. The multiple calibration point structures 140 are respectively located on the multiple calibration planes 111.

[0060] In this embodiment, multiple feature light-emitting point structures 140 are sequentially spaced along the circumference of the support frame 110. The light-emitting surface area of ​​one feature light-emitting point structure 140 is smaller than that of the other feature light-emitting point structures 140, while the other feature light-emitting point structures 140 have the same light-emitting surface area. This arrangement facilitates the encoding and sorting of feature points. By simultaneously performing rectangle recognition and minimum feature point recognition, the feature points are strictly identified according to the encoding order during the recognition process, preventing any disorder in the feature point encoding order and ensuring the real-time accurate positioning of the handheld measuring device 100.

[0061] In this embodiment, the light plane emitted by the linear laser 130 is parallel to the vertical direction. Furthermore, the linear laser 130 is an adjustable laser, and the thickness of its emitted light stripe can be adjusted. This adjustment is performed during installation and not during actual measurement. In this embodiment, the linear laser 130 is built into the support frame 110, thus not occupying external space and avoiding interference with the imaging equipment 200. Additionally, one linear laser 130 is sufficient to meet the testing requirements. However, it should be understood that overlapping light planes of multiple linear lasers 130 also meet the testing requirements. Therefore, the specific number of linear lasers 130 is not uniquely limited here.

[0062] In this embodiment, the orthographic projection of the light plane emitted by the linear laser 130 overlaps with the axis of symmetry of the support frame 110, ensuring that the camera device 200 can acquire uniform linear laser information within its maximum field of view. The light plane of the linear laser intersects the surface of the object under test 500, forming a light strip at the intersection, which feeds back two-dimensional surface information of the object under test 500 to the camera device 200. If the light plane intersects with the same plane, the light strip appears as a straight line; if the light plane intersects with different planes, the light strip appears as a segmented straight line with different heights; if the light plane intersects with a curved surface, the light strip appears as a curve. Different types of light stripes feed back different two-dimensional surface information to the camera device 200.

[0063] In this embodiment, the handle 120 and the support frame 110 can be connected as a whole through technologies such as 3D printing, which can reduce the processing difficulty and avoid the processing and assembly errors caused by separate manufacturing and reassembly, thus improving the measurement accuracy.

[0064] In this embodiment, the shape of the feature points displayed by the feature light-emitting point structure 140 is preferably circular.

[0065] Compared with the prior art, the handheld measuring device provided in this embodiment adopts a line structured light measurement model. The line laser emitted by the linear laser 130 intersects with the surface of the object under test 500, forming a light stripe at the intersection. At the same time, due to the staggered distribution of the calibration planes 111 and the uneven surface of the support frame 110, the calibration points formed by the calibration point structure 140 form a non-coplanar three-dimensional distribution. Under different postures, specific sorting information can be formed, avoiding the influence of posture ambiguity on the spatial posture estimation of the handheld measuring device. Thus, the real-time posture information of the handheld measuring device 100 can be obtained. Furthermore, since the support frame 110 is a ring structure with a gap in the middle, a camera device 200 above the handheld measuring device 100 can simultaneously collect the posture information and light stripe information of the handheld measuring device 100. The three-dimensional posture information is used to make up for the missing dimension information of the light stripe, and finally, the three-dimensional information of the surface of the object under test 500 can be established. Using the handheld measuring device 100 of this application eliminates the need for multiple cameras for shooting, avoiding the problems of reduced measurement accuracy and insufficient reliability caused by calibration and conversion of multiple cameras, thus improving the accuracy of measurement.

[0066] Some embodiments employ, for example Figure 2 The structure shown. See also Figure 2 In order to ensure that specific sorting information can be formed and to facilitate the determination of the pose of the handheld measuring device 100, the arrangement of the calibration point structures 120 on two adjacent calibration planes 111 is different.

[0067] Based on the above embodiments, see Figure 2The support frame 110 is preferably a ring structure with a polygonal construction. Based on this structure, some of the calibration planes 111 can be formed by two adjacent sides of the polygon, and at least three calibration point structures 140 are provided along the extension direction of these calibration planes 111, such that the calibration point structures 140 on a single calibration plane 111 are distributed in a triangle; other calibration planes 111 can be formed by a single side of the polygon, and multiple calibration point structures 140 can be provided along the extension direction of these calibration planes 111, or a single calibration point structure 140 can be provided on these calibration planes 111. Ultimately, adjacent calibration planes 111 exhibit a distribution pattern that varies horizontally and vertically. Some calibration planes 111 themselves have multiple calibration point structures 111 arranged in a triangular pattern. All calibration point structures 111 are then arranged in a ring along the circumference of the support frame 110. This allows the feature points formed by the calibration point structures 111 to simultaneously possess multiple distribution patterns, including ring, horizontal, vertical, and triangular distributions, further avoiding the influence of pose ambiguity on the spatial pose estimation of the handheld measuring device 100. In this embodiment, the support frame 110 is exemplarily shown as a regular octagonal ring structure. Of course, regular hexagonal, regular pentagonal, and other structures can also be used, which will not be listed here.

[0068] Some embodiments employ, for example Figure 2 The structure shown. See also Figure 2 There are two handles 120. The two handles 120 are symmetrically distributed on opposite sides of the support frame 110 with the axis of symmetry as the axis. Users can flexibly choose the way to hold the handles 120 according to their own needs, which improves the versatility and reliability of the handheld measuring device 100.

[0069] Some embodiments employ, for example Figure 2 The structure shown. See also Figure 2 The handle 120 is preferably ring-shaped, so that the camera device 200 can collect the two-dimensional surface information fed back by the light strip through the hole in the middle of the handle 120, ensuring the comprehensiveness and reliability of information collection.

[0070] Some embodiments employ, for example Figure 4 and Figure 5 The structure shown. See also Figure 4 and Figure 5 To reduce the installation difficulty of the linear laser 130 and ensure the reliability of the assembly, a first mounting hole is formed in the support frame 110, which is gradually inclined downward from the inside to the outside. The inner end face of the first mounting hole forms a laser emission port. The linear laser 130 is inserted into the first mounting hole, and an elastic fixing structure 150 is provided at the laser emission port. The elastic fixing structure 150 is configured with a pre-tightening force to make the linear laser 130 move away from the laser emission port.

[0071] Some embodiments employ, for example Figure 4 and Figure 5 The structure shown. See also Figure 4 and Figure 5 A limiting hole 112 perpendicular to the first mounting hole is provided on the side wall near the laser emission port. The elastic fixing structure 150 includes a limiting block 151 and an elastic element 152. The limiting block 151 has a first limiting surface that fits and limits the emission surface of the linear laser 130 to achieve axial limiting of the linear laser 130 and prevent the linear laser 130 from shaking. The limiting block 151 also has a second limiting surface that fits and limits the outer peripheral surface of the linear laser 130 to achieve radial limiting of the linear laser 130 and prevent the linear laser 130 from rotating. The elastic element 152 is disposed in the limiting hole 112 and connected to the limiting block 151. The elastic element 152 is configured with a preload force to move the limiting block 152 toward the central axis of the first mounting hole. In specific implementation, the elastic element 152 can adopt a structure such as a spring or a rubber block, and is not limited to one; the limiting block 151 itself has a certain elasticity to avoid rigid collision with the linear laser 130 and damage to the linear laser 130.

[0072] Some embodiments employ, for example Figure 3 The structure shown. See also Figure 3 A second mounting hole with a downward opening is formed on the calibration plane 111. The calibration point structure 140 includes a light source 141, a light guide post 142, and a lens 143. The light source 141 is disposed within the second mounting hole. The light guide post 142 covers the upper side of the light source 141, and both the outer peripheral surface and the upper surface of the light guide post 142 are covered by a mask plate 144. The lens 143 covers the upper part of the light guide post 142. The lens 143 is attached to the mask plate 144 on the upper surface of the light guide post 142. Specific embodiments of the light source 141 include, but are not limited to, infrared light-emitting diodes (e.g., infrared light-emitting diodes with a wavelength of 850nm). The advantages of using infrared light-emitting diodes are that the light they produce has good stability, high brightness, low power consumption, small size, and no special power supply requirements, making them suitable for use in handheld devices.

[0073] In this embodiment, the mask plate 144 is used to correct the light so that the light is more in line with the circular feature;

[0074] More specifically, a mask plate 144 (not shown in the figure) can also be covered on the rear side of the light guide post 142 to further improve the correction effect on the light.

[0075] In some embodiments, the light guide post 142 is made of transparent acrylic material, and both its upper and lower surfaces are roughened to give them a certain uneven structure, which helps to make the light source emit light more evenly. The lower surface of the light guide post 142 includes a surface that covers and adheres to the light source 141. Acrylic is a malleable polymer material with good transparency, chemical stability, easy dyeing and processing, and good light guiding properties for light-emitting diodes, making it suitable for infrared light-emitting diode light sources.

[0076] In some embodiments, the upper surface of the mask plate 144 located above the light guide post 142 is covered with a light-diffusing coating. In addition to blocking and absorbing stray light, the coating can also diffuse the light generated by the light source 141, making the light source more uniform and the marker features clearer when the camera device 200 images.

[0077] In some embodiments, the lens 143 is a mobile phone camera lens to ensure the absolute roundness of the feature points.

[0078] Some embodiments employ, for example Figure 5 The structure shown. See also Figure 5 The angle α between the light output direction and the vertical direction of the linear laser 130 is 20° to 40°. Optionally, the angle α is 30°. Provided that the light plane passes strictly through the center of symmetry of the support frame 110, this tilted setting ensures that the camera device 200 can acquire two-dimensional image information of uniformly thick light stripes within the maximum field of view.

[0079] Some embodiments use, for example Figure 6 The structure shown. See also Figure 6 The support frame 110 also forms a battery mounting space with an opening on one side, and a battery 160 is installed in the battery mounting space. A removable cover 170 is provided on the opening side of the battery mounting space. Multiple calibration point structures 140 are electrically connected to the battery 160. The opening of the battery mounting space is preferably located on the lower surface or the outer periphery of the support frame 110, avoiding its placement on the calibration plane 111. In this embodiment, the cover 170, in conjunction with the support frame 110, secures the battery 160, preventing it from shaking, ensuring power supply stability, and facilitating battery replacement. Specifically, the power of the battery 160 is determined based on the number and power of the characteristic light-emitting point structures 140. In this embodiment, the battery 160 is exemplarily set as a single 1.5-volt battery, which can meet the power supply requirements of eight parallel light sources 141.

[0080] Based on the same inventive concept, this application also provides a measurement system, including a workbench 400, a measurement frame 300, a camera device 200, and the aforementioned handheld measurement device 100; the workbench 400 is used to support the object to be measured 500; the measurement frame 300 is placed on the workbench 400, and a measurement space for accommodating the object to be measured 500 is formed within the measurement frame 300; the camera device 200 is located on top of the measurement frame 300 to provide the maximum measurement space within the field of view of the camera device 200, and the camera of the camera device 200 is set vertically downward.

[0081] In this embodiment, the camera of the camera device 200 is vertically downward, so that the camera device 200 can be perpendicular to the object being measured 500 during part of the measurement, and ensure that the feature points are fully exposed in the field of view of the camera device 200, which not only meets the measurement requirements of the user, but also improves the user experience.

[0082] The measuring frame 300 in this embodiment is assembled from aluminum profiles. Adjacent aluminum profiles are fixed together by L-shaped connecting brackets and threaded fasteners, which reduces the weight of the measuring frame 300 and facilitates loading, unloading and transportation.

[0083] In this embodiment, the measurement system adopts a line structured light measurement model. The linear laser emitted by the linear laser 130 intersects with the surface of the object under test 500 to form a light stripe. Through pre-calibration, the transformation relationship H1 between the light plane where the linear laser is located and the feature point coordinate system on the upper surface of the handheld measuring device 100 can be obtained. Then, the image of the two-dimensional information of the light stripe is acquired by the camera device 200. The two-dimensional information of the light stripe is transformed into the feature point coordinate system through H1. The feature points of the handheld testing device 100 are pre-coded and sorted, and the camera device 200 can capture the circular infrared information of the feature points and perform real-time positioning. The two-dimensional information of the light stripe is combined with the light plane information and the three-dimensional information of the movement of the handheld testing device 100 to obtain the three-dimensional surface point cloud of the object under test 500. The image is formed in the camera coordinate system of the camera device 200 to complete the measurement.

[0084] The process involves using a camera device 200 to capture and identify feature points on a handheld measuring device 100, thereby representing the real-time pose of the handheld measuring device 100. This real-time pose compensates for the missing dimensional information in the light stripe, constructing the three-dimensional surface information of the object under test 500. Measurement of the object under test 500 is then completed by moving the handheld measuring device 100. The extraction of the light stripe employs a fusion of the extreme value method and the gray-scale centroid method, achieving faster and more accurate extraction of the light stripe center within a smaller threshold range.

[0085] The relative positional relationship between the laser beam plane and the feature points of the handheld measuring device 100 is fixed. The real-time pose matrix H2 of the feature points on the handheld measuring device 100 is solved and optimized using an orthogonal iterative algorithm. Since this algorithm has the characteristics of high accuracy and high efficiency, and the feature points on the handheld measuring device 100 have a unique encoding order, the camera device 200 can accurately and efficiently locate the feature points of the handheld measuring device 100 in real time, thereby obtaining real-time three-dimensional surface information.

[0086] Compared with the prior art, the measurement system provided in this embodiment uses the handheld measuring device 100 described above. During use, the handheld measuring device 100 is located between the object to be measured 500 and the camera device 200. The camera device 200 can simultaneously collect the attitude information and light stripe information of the handheld measuring device 100. The three-dimensional attitude information is used to make up for the missing dimension information of the light stripe, and finally the three-dimensional information of the surface of the object to be measured can be established. There is no need for multiple cameras to take pictures, avoiding the problems of reduced measurement accuracy and insufficient reliability caused by calibration conversion of multiple cameras, thus improving the accuracy of measurement.

[0087] In some embodiments, to obtain accurate relative positional relationships between feature points on the handheld measuring device 100, two camera devices 200 are used for calibration, forming a binocular camera structure. The binocular camera structure mimics the distribution of the human eye, with the two camera devices 200 positioned at the same horizontal height. The field of view of the two camera devices 200 are at an angle of 150° to 170°, and the distance between them is between 30cm and 50cm. The specific angle distribution and distance depend on the size of the object being measured 500. Furthermore, the accuracy of the binocular camera structure in calibrating the planar target is within 0.08mm, which can, as much as possible, offset the processing errors of the feature points on the handheld measuring device 100, resulting in a more accurate relative positional relationship between feature points on the handheld measuring device 100 and improving the scanning measurement accuracy.

[0088] Some embodiments employ, for example Figure 1 and Figure 7 The structure shown. See also Figure 1 and Figure 7 The top of the measuring frame 300 is provided with a mounting bracket 600, which forms a contact plane parallel to the vertical direction. The camera device 200 is in contact with the contact plane, and the camera device 200 and the mounting bracket 600 are fixedly connected by at least two fasteners. In this embodiment, multiple connection points are formed between the camera device 200 and the mounting bracket 600, and each connection point is equipped with a corresponding fastener. At the same time, the contact with the contact plane ensures vertical setting, avoiding large positional movement errors of the camera device 200 during measurement.

[0089] Some embodiments employ, for example Figure 1 and Figure 7 The structure shown. See also Figure 1 and Figure 7 The mounting bracket 600 includes a first mounting plate 610 and a second mounting plate 620 perpendicular to and connected to the first mounting plate 610. The second mounting plate 620 extends downward, and a reinforcing rib plate 630 is provided between the second mounting plate 620 and the first mounting plate 610. The first mounting plate 610 is fixed to the measuring frame by threaded fasteners, and the second mounting plate 620 forms a contact plane and is fixed to the measuring frame 300 by at least two fasteners.

[0090] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A handheld measuring device, characterized in that, include: The support frame is an axially symmetrical ring-shaped frame. The inner ring surface of the support frame forms a laser light outlet. The upper surface of the support frame is provided with multiple calibration planes alternately along the circumference of the support frame. Adjacent calibration planes are staggered vertically, and each calibration plane is perpendicular to the vertical direction. A handle is provided on the support frame; A linear laser is disposed within the support frame. The laser's emission direction is tilted downwards, and its emission surface faces the laser emission port. On a plane perpendicular to the vertical direction, the orthographic projection of the plane emitted by the linear laser overlaps with the axis of symmetry of the support frame. Multiple calibration point structures are respectively set on multiple calibration planes.

2. The handheld measuring device as described in claim 1, characterized in that, The device has two handles, which are symmetrically distributed on opposite sides of the support frame with the axis of symmetry as the axis.

3. The handheld measuring device as described in claim 1, characterized in that, The arrangement of the calibration points on two adjacent calibration planes is different.

4. The handheld measuring device as described in claim 1, characterized in that, The support frame forms a first mounting hole that gradually slopes downwards from the inside to the outside, and the inner end face of the first mounting hole forms the laser light outlet; The linear laser is inserted into the first mounting hole, and an elastic fixing structure is provided at the laser output port. The elastic fixing structure is configured with a pre-tightening force to move the linear laser away from the laser output port.

5. The handheld measuring device as described in claim 4, characterized in that, A limiting hole perpendicular to the first mounting hole is formed on the side wall near the laser emission port. The elastic fixing structure includes: The limiting block has a first limiting surface that conforms to and limits the light-emitting surface of the linear laser, and a second limiting surface that conforms to and limits the outer peripheral surface of the linear laser; and An elastic element is disposed within the limiting hole and connected to the limiting block. The elastic element is configured with a preload force that causes the limiting block to move toward the central axis of the first mounting hole.

6. The handheld measuring device as described in claim 1, characterized in that, A second mounting hole with a downward opening is formed on the calibration plane, and the calibration point structure includes: The light source is located inside the second mounting hole; A light guide post is positioned above the light source, and both its outer peripheral surface and upper surface are covered with a mask plate; and A lens is placed on the upper part of the light guide post.

7. The handheld measuring device as described in claim 1, characterized in that, The angle between the light output direction and the vertical direction of the linear laser is 20° to 40°.

8. The handheld measuring device as described in claim 1, characterized in that, The support frame also forms a battery mounting space with an opening on one side, and a battery is installed in the battery mounting space. The opening side of the battery mounting space is detachably covered with a cap, and the plurality of calibration point structures are electrically connected to the battery respectively.

9. A measurement system, characterized in that, include: The worktable is used to support the object being measured. A measuring frame is placed on the worktable, and a measuring space is formed within the measuring frame to accommodate the object to be measured. A camera device is located at the top of the measuring frame, with the camera of the camera device positioned vertically downwards; as well as The handheld measuring device as described in any one of claims 1-8.

10. The measurement system as described in claim 9, characterized in that, The top of the measuring frame is provided with a mounting bracket, which forms a contact plane parallel to the vertical direction. The camera device is in contact with the contact plane, and the camera device is fixedly connected to the mounting bracket by at least two fasteners.

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