Intermediate standards and automated calibration systems for scanners
By designing the annular recognition area and recognition head of the intermediate standard, the problem of positional limitations in the scanner calibration process is solved, achieving higher calibration accuracy and flexibility, and making it suitable for automated field applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SCANTECH (HANGZHOU) CO LTD
- Filing Date
- 2025-08-12
- Publication Date
- 2026-07-03
AI Technical Summary
In existing scanner calibration processes, the relative positions of the tracker and the scanner are quite limited, and the automated field environment is not fixed, resulting in insufficient flexibility and applicability of the calibration process.
An intermediate standard was designed, including an annular recognition area and a recognition head. The annular recognition area is composed of several adhesive surfaces and is set on the main body for recognition by scanners and trackers. The recognition head protrudes from the main body and is equipped with marking points. The annular recognition area and the recognition head are flexibly distributed, reducing the limitation on the position.
It increases the flexibility of scanner and tracker placement, expands the calibration area, improves calibration accuracy and applicability, and enhances the flexibility and accuracy of automated calibration.
Smart Images
Figure CN224455695U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of 3D scanner technology, specifically to an intermediate standard and an automated scanner calibration system. Background Technology
[0002] Typically, two parameters in the scanner's structural parameters need to be obtained through calibration: one is the scanner's binocular camera extrinsic parameters (described below, first calibration), and the other is the relative positional relationship between the scanner's camera coordinate system and the navigation skeleton coordinate system (described below, second calibration).
[0003] In current automated ball scanning scenarios, when calibrating a scanner, a tracker and an intermediate reference object are usually used to place the ball scanner in the tracker's field of view. Then, the relevant structural parameters of the scanner are calculated using the target data observed by the ball scanner.
[0004] Current intermediate reference points typically consist of two sets of markers: side markers for the tracker and front markers for the scanner. These markers are usually distributed at a 90° angle to each other. During use, the side markers need to be positioned as directly as possible opposite the tracker, and the front markers as directly opposite the scanner. This results in numerous limitations on the relative positions of the tracker and scanner during calibration, restricting their application in the field.
[0005] In addition, during the current calibration process, scanners usually need to collect data at a designated location, but the automated field environment is usually not fixed, and sometimes the robotic arm cannot reach the designated location, which limits the application and reduces the degree of freedom. Utility Model Content
[0006] To address the aforementioned shortcomings of existing technologies, an intermediate standard and an automated calibration system for scanners are provided. This reduces the limitations on the placement of trackers and scanners in the calibration process, making the formulation of automated calibration procedures more flexible and improving the applicability and versatility of the intermediate standard and the calibration system.
[0007] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:
[0008] Firstly, an intermediate standard is used in the calibration of 3D scanners; the intermediate standard includes...
[0009] The main body has a ring-shaped recognition area; within the ring-shaped recognition area are several recognition markers for identification by a scanner located above the main body and a tracker located at any point around the main body.
[0010] The identification head has several identification heads on the main body, and the identification heads protrude from the main body in the height direction; several identification mark points are provided on the outer surface of each identification head, and the tracker can identify some of the mark points on the identification head at any point around the main body.
[0011] According to the above technical solution, the annular recognition area includes at least two layers, with a set angle between the annular recognition area located in the upper layer and the annular recognition area located in the lower layer; at least one layer of the annular recognition area is recognized by the scanner, and all annular recognition areas are recognized by the tracker.
[0012] According to the above technical solution, the annular identification area is composed of several adhesive surfaces, and a marking point is pasted in each adhesive surface.
[0013] According to the above technical solution, it includes at least three recognition heads, all of which are distributed at intervals around the periphery of the main body, and the three recognition heads are not on the same straight line.
[0014] According to the above technical solution, the recognition head adopts an island-shaped structure or a spherical structure, and several adhesive surfaces are evenly provided on the outer surface of the recognition head, with a marking point pasted in each adhesive surface.
[0015] According to the above technical solution, the identification head is fixedly connected to the main body by bolt fasteners.
[0016] According to the above technical solution, a top recognition area is provided in the middle of the main body located in the ring recognition area, and several marker points are provided in the top recognition area.
[0017] According to the above technical solution, the top identification area is set as a plane, or a concave curved surface, or a convex curved surface.
[0018] According to the above technical solution, a low-reflective layer is applied to the outer surface of the main body.
[0019] According to the above technical solution, the main body is hollow inside.
[0020] According to the above technical solution, the main body is provided with a clamping part that facilitates the user's fingers to pick up and put down the device.
[0021] According to the above technical solution, a support surface is provided at the bottom of the main body.
[0022] According to the above technical solution, the main body is an inverted bowl-shaped shell structure; a top identification area is provided on the top surface of the shell, and the marking points of the top identification area are arranged horizontally; an annular identification area is provided on the periphery of the shell, and the annular identification area is divided into upper and lower layers, with the marking points of the lower annular identification area arranged vertically and the marking points of the upper annular identification area arranged at an angle.
[0023] It contains three recognition heads, each with an island-shaped structure. Each recognition head includes a top plane with marking points and an annular side. The recognition heads are fixedly connected to the upper annular recognition area by fasteners, and the three recognition heads are arranged in a triangular pattern in the upper annular recognition area.
[0024] Secondly, the automated calibration system includes a scanner, a robotic arm for holding the scanner, and a tracker; it also includes any of the intermediate standards described above.
[0025] This utility model has the following beneficial effects:
[0026] 1. Based on the scanner's position and the setting of the annular recognition area, the tracker is not limited to a few fixed placement positions in the second calibration, allowing for more freedom and flexibility in its placement. The annular recognition area and the recognition markers on the scanner can be identified around the perimeter of the central standard. Furthermore, to further optimize the depth direction parameter in the relative positional relationship between the two coordinate systems during the second calibration, several recognition heads are set on the main body. The tracker can identify recognition markers located on the sides and rear of the central standard from any position around it, thereby improving the accuracy of the second calibration process.
[0027] Based on the above measures, the intermediate standard is set up as follows:
[0028] First, in the first and second calibrations, the limitations on the placement of the intermediate standard can be effectively reduced, and the area for the scanner can be expanded.
[0029] Secondly, the scanner has a larger area, making it easier for the tracker to identify the identification marks on the scanner. In addition, the scanner's ring-shaped identification area and identification head allow the tracker to identify effective identification marks for calibration around the main body, and the tracker's placement is also more flexible.
[0030] Third, the scanner's placement area is larger, the control path settings for the robotic arm carrying the scanner are more diverse, and the automated data collection process is more flexible.
[0031] 2. At least two layers of annular recognition surfaces are provided to ensure that the scanner and tracker can detect the recognition mark points on both sides of the central standard, thereby increasing the flexibility of the scanner and tracker arrangement.
[0032] 3. The three recognition heads are arranged in a triangle on the main body to avoid mutual obstruction between the recognition heads, which would prevent the tracker from recognizing the recognition marks on the front and rear recognition heads and improve the applicability of the intermediate standard.
[0033] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it according to the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. The specific implementation methods of this utility model are given in detail in the following embodiments and their accompanying drawings. Attached Figure Description
[0034] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and are used to explain the present invention, but do not constitute an undue limitation of the present invention.
[0035] Figure 1 This is a structural schematic diagram of an embodiment provided by this utility model;
[0036] Figure 2 This is a structural schematic diagram of an embodiment provided by this utility model;
[0037] In the diagram, 1. Main body; 2. Circular recognition area; 2-1. Adhesive surface; 3. Recognition mark point; 4. Recognition head; 5. Top recognition area; 6. Clamping part. Detailed Implementation
[0038] The following is in conjunction with the appendix Figures 1-2 The principles and features of this utility model are described below. The examples given are for illustrative purposes only and are not intended to limit the scope of this utility model. The utility model is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of this utility model will become clearer from the following description and claims. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this utility model.
[0039] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.
[0040] Unless otherwise defined, 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 invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0041] Reference Figures 1-2 As shown, the intermediate standard provided by this utility model is applied in the calibration of 3D scanners.
[0042] Example 1
[0043] The intermediate standard includes
[0044] The main body 1 has a ring-shaped recognition area 2 on it; several recognition markers 3 are provided in the ring-shaped recognition area for recognition by a scanner located above the main body and a tracker located at any point around the main body.
[0045] The identification head 4 has several identification heads on the main body, and the identification heads protrude from the main body in the height direction; several identification mark points 3 are provided on the outer surface of each identification head, and the tracker can identify some of the mark points on the identification head at any point around the main body.
[0046] In this embodiment, several marker points located on the annular recognition area are used, in part, by a scanner for calibrating the extrinsic parameters of the scanner's binocular camera (hereinafter referred to as the first calibration); and in part or all of them, by a tracker for calibrating the relative positional relationship between the scanner's camera coordinate system and the navigation skeleton coordinate system (hereinafter referred to as the second calibration). Due to the setting of the annular recognition area, compared to the prior art where the scanner is located directly above the calibration plate; in the first calibration, the scanner's position can be offset by a certain angle relative to directly above, making the scanner's placement more flexible, and the strategy for the robotic arm to control the scanner's movement more free and diverse.
[0047] Similarly, based on the scanner's position and the setting of the annular recognition area, in the second calibration, the tracker is not limited to a few fixed placement positions, and its placement is more free and flexible. The annular recognition area and the recognition markers on the scanner can be identified around the perimeter of the central standard. Furthermore, in the second calibration, to further optimize the depth direction parameter in the relative positional relationship between the two coordinate systems, several recognition heads are set on the main body. The tracker can identify recognition markers located on the sides and rear of the central standard from any position around it, thereby improving the accuracy of the second calibration process.
[0048] Based on the above measures, the setting of this intermediate standard can reduce the restrictions on the placement of the scanner and tracker in both the first and second calibrations. The scanner and tracker do not need to be in a specified position, which greatly improves the flexibility of the scanner calibration position and increases the tolerance to automated field conditions.
[0049] In Embodiment 1, the annular recognition area comprises at least two layers, with a predetermined angle between the uppermost and lowermost annular recognition areas; at least one layer of the annular recognition area is recognized by the scanner, and all annular recognition areas are recognized by the tracker. The uppermost annular recognition area is primarily used for recognition by the scanner in the first calibration, and for recognition by both the scanner and the tracker in the second calibration. The lowermost annular recognition area is primarily used for recognition by the tracker in the second calibration.
[0050] Example 2
[0051] Based on Embodiment 1, a preferred configuration of the annular recognition area is provided. The annular recognition area is composed of several adhesive surfaces 2-1, with a marking point pasted within each adhesive surface. However, the configuration of the annular recognition area is not limited to Embodiment 2; multiple points can also be pasted on each surface, preferably a plane.
[0052] Example 3
[0053] Based on Examples 1 and 2, to further improve the applicability of this intermediate standard and avoid mutual obstruction between the recognition heads when the intermediate standard is placed in a certain state, preventing the tracker from only recognizing the recognition mark point on one recognition head, a preferred configuration of the recognition heads is provided. This configuration includes at least three recognition heads, all spaced apart around the perimeter of the main body, and the three recognition heads are not on the same straight line. That is, at least three recognition heads are located at the three corners of a triangle. Regardless of the tracker's position on any part of the intermediate standard's perimeter, it can recognize the recognition mark points on both the front and rear recognition heads, thereby achieving depth direction calibration in the second calibration.
[0054] In embodiments 1-3, a preferred structural form of the recognition head is provided. The recognition head adopts an island-shaped or spherical structure, and a plurality of adhesive surfaces are evenly distributed on the outer surface of the recognition head, with a marking point adhered to each adhesive surface. The recognition head is fixedly connected to the main body by bolt fasteners. This fastener can be located on the annular recognition area or on the top recognition area.
[0055] Example 4
[0056] Based on embodiments 1-3, in order to improve the calibration accuracy of the scanner, a top recognition area 5 is provided in the middle of the main body located in the annular recognition area, and several marking points are provided in the top recognition area.
[0057] The top identification area is either a flat surface, a concave curved surface, or a convex curved surface; several marker points are distributed at intervals in the top identification area.
[0058] In Examples 1-4, to improve calibration accuracy, a low-reflectivity layer is applied to the outer surface of the main body. The low-reflectivity layer can be made of a non-reflective material or it can be a low-reflectivity layer applied later; this prevents the main body from reflecting laser light, which could interfere with the calibration process of the scanner or tracker through the marked points, thus improving calibration accuracy. In this example, the low-reflectivity layer has a frosted surface.
[0059] In embodiments 1-4, the main body is hollow to save materials. This hollow design reduces the weight of the intermediate standard and saves materials, thus lowering costs.
[0060] In embodiments 1-4, a clamping part 6 is provided on the main body to facilitate the user's fingers to pick up and put down the device. The clamping part can be a handle-like structure connected to the outside of the housing, such as a protrusion or grip; or it can be a hole or groove recessed into the main body for the fingers to insert and pinch.
[0061] In embodiments 1-4, a support surface is provided at the bottom of the main body. The device is placed in a designated area via the support surface.
[0062] In conjunction with the above embodiments, the following is given: Figure 1 The intermediate standard device with the preferred structure shown is as follows: The main body is an inverted bowl-shaped shell structure; a top identification area is provided on the top surface of the shell, and the marking points in the top identification area are arranged horizontally; an annular identification area is provided on the periphery of the shell, and the annular identification area is divided into upper and lower layers, with the marking points in the lower annular identification area arranged vertically and the marking points in the upper annular identification area arranged at an angle.
[0063] It contains three recognition heads, each with an island-shaped structure. Each recognition head includes a top plane with marking points and an annular side. The recognition heads are fixedly connected to the upper annular recognition area by fasteners, and the three recognition heads are arranged in a triangular pattern in the upper annular recognition area.
[0064] In this intermediate standard, the identification markers are now distributed in a ring-like pattern. Compared to the unidirectional distribution of side points on existing calibration plates, the new structure allows the markers to be partially observed from all directions around the main body. Therefore, the placement of the intermediate standard is no longer limited by the orientation of the markers, and the scanner can also expand its observation range. The placement of the intermediate standard, scanner, and tracker is more flexible. Consequently, the markers on the scanner can be more easily and completely observed by the tracker.
[0065] This invention also provides an automated calibration system, including a scanner, a robotic arm for holding the scanner, a tracker, and an intermediate standard as described above.
[0066] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Those skilled in the art can readily implement this utility model based on the accompanying drawings and the above description. However, any modifications, alterations, or variations made by those skilled in the art without departing from the scope of the utility model's technical solution, utilizing the disclosed technical content, are equivalent embodiments of this utility model. Furthermore, any equivalent changes, alterations, or variations made to the above embodiments based on the essential technology of this utility model are still within the protection scope of this utility model's technical solution.
Claims
1. An intermediate standard for use in the calibration of a three-dimensional scanner, characterized in that: The intermediate standard includes The main body has a ring-shaped recognition area; within the ring-shaped recognition area are several recognition markers for identification by a scanner located above the main body and a tracker located at any point around the main body. The identification head has several identification heads on the main body, and the identification heads protrude from the main body in the height direction; several identification mark points are provided on the outer surface of each identification head, and the tracker can identify some of the mark points on the identification head at any point around the main body.
2. The intermediate standardizer of claim 1, wherein: The annular recognition area includes at least two layers, with a set angle between the annular recognition area in the upper layer and the annular recognition area in the lower layer; at least one annular recognition area is recognized by the scanner, and all annular recognition areas are recognized by the tracker.
3. The intermediate standardizer of claim 2, wherein: The annular identification area consists of several adhesive surfaces, with a marker point pasted in each adhesive surface.
4. The intermediate standardizer of claim 1, wherein: It includes at least three recognition heads, all of which are spaced apart on the periphery of the main body and are not on the same straight line.
5. An intermediate standard according to claim 1 or 4, characterized in that: The recognition head adopts an island-shaped or spherical structure, and several adhesive surfaces are evenly distributed on the outer surface of the recognition head, with marking points pasted in each adhesive surface.
6. The intermediate standard of claim 1 or 4, wherein: The identification head is fixedly connected to the main body by bolt fasteners.
7. The intermediate standardizer of claim 1, wherein: A top recognition area is located in the middle of the ring-shaped recognition area, and several marker points are set in the top recognition area.
8. The intermediate standardizer of claim 7, wherein: The top identification area can be a flat surface, a concave curved surface, or a convex curved surface.
9. The intermediate standardizer of claim 1, wherein: A low-reflective layer is applied to the outer surface of the main body.
10. The intermediate standardizer of claim 1, wherein: The main body is hollow inside.
11. An intermediate standard according to claim 1 or 10, characterized in that: The main body is equipped with a gripping part that makes it easy for users to pick up and put down their fingers.
12. The intermediate standardizer of claim 1, wherein: A support surface is provided at the bottom of the main body.
13. The intermediate standardizer of claim 1, wherein: The main body is an inverted bowl-shaped shell structure; a top identification area is provided on the top surface of the shell, and the marking points in the top identification area are arranged horizontally; an annular identification area is provided on the periphery of the shell, and the annular identification area is divided into upper and lower layers, with the marking points in the lower annular identification area arranged vertically and the marking points in the upper annular identification area arranged at an angle. It contains three recognition heads, each with an island-shaped structure. Each recognition head includes a top plane with marking points and an annular side. The recognition heads are fixedly connected to the upper annular recognition area by fasteners, and the three recognition heads are arranged in a triangular pattern in the upper annular recognition area.
14. An automated calibration system comprising a scanner, a robotic arm for holding the scanner, and a tracker; characterized by: It also includes the intermediate standard as described in any one of claims 1-13.