Novel dynamic capture mark capable of being used for fusion of human body CT image and human body epidermis visual image

Abstract

The invention discloses a novel dynamic capture marker capable of being used for fusion of a human body CT image and a human body epidermis visual image, and relates to the field of medical auxiliary equipment. The mark point is made of a high-density material, can be accurately identified by a camera in a dynamic capture system, and can also be clearly visible in CT scanning. The innovative design allows a seamless correction and integration process to be established between dynamic capture and CT imaging, thereby greatly improving data accuracy and application flexibility.

Description

Technical Field

[0001] The present invention relates to the field of medical auxiliary equipment, and mainly relates to a novel dynamic capture marker that can be used for fusing a human CT image with a human epidermis visual image. Background Art

[0002] In the fields of modern film production, video game development, and medical research, motion capture (MoCap) technology is an indispensable tool that allows the accurate capture of dynamic information of the human body or other objects and converts this information into a digital model. Motion capture systems usually rely on markers attached to the captured object to track its movement, and these markers must be clearly identified by a specially designed camera. Patents such as CN114559670A, a method and device for making a reflective marker ball, CN220526945U, a plug-in light-emitting diode lamp bead for use with binocular optical positioning equipment, and CN220526538U, a reflective marker ball, provide visual surface motion capture technology solutions. CN116940638A core-shell dye, a near-infrared absorbing composition containing it, and a near-infrared absorbing film patent indicate that infrared absorption can be achieved by coating the surface of the positioning ball with a core-shell dye, which is helpful for visual tracking.

[0003] On the other hand, computer tomography (CT) technology plays a key role in medical imaging and scientific research, providing detailed images of the internal structure of an object. Patents such as CN204932612U, a body surface positioning device for radiotherapy of esophageal cancer, CN114149569A, a conjugated carbon iodine polymer and its preparation and application for preparing positioning markers, and CN116823948A, a method, device and equipment for determining the center of a reflective marker ball in three-dimensional medical imaging, all provide good ideas for imaging and surface markers in CT, but they cannot be applied to dynamic capture.

[0004] It can be seen that existing technologies are often unable to effectively combine motion capture data with CT images, because standard motion capture markers are difficult to identify in CT scans, which limits the potential for collaborative application of the two technologies.

[0005] The limitations of traditional motion capture (mocap) markers in CT scanning mainly stem from their materials and design, and have caused significant restrictions on their application in medical imaging and scientific research. Traditional mocap markers are usually made of reflective or luminous materials, such as reflective plastics or devices with LED lights, so that they can be easily identified and tracked by mocap cameras. The design of these markers is optimized to achieve the best performance in specific optical mocap systems, including a spherical design to ensure that they can be captured by the camera from any angle. However, these materials and designs face significant limitations during CT imaging.

[0006] First, the materials of traditional motion capture markers often do not have sufficient contrast in CT scans because these materials are optimized primarily for optical recognition rather than for X-ray absorption or scattering. As a result, these markers may not be clearly visible on CT images, making it impossible to effectively use CT scans to accurately calibrate or compare motion capture data. In addition, because CT scans rely on the different absorption rates of X-rays by materials of different densities, traditional lightweight plastics or light-emitting devices lack the ability to produce clearly recognizable outlines on CT images.

[0007] Second, even when they can be recognized by CT scans, the standard spherical design of the markers may not be suitable for accurate 3D positioning and correction. In CT imaging, the markers need to have a specific (asymmetric) geometry to clearly identify the spatial position under X-ray, and the design of traditional motion capture markers often does not take this into account.

[0008] Therefore, these limitations hinder the application of traditional motion capture technology in high-precision medical imaging and biomechanics research combined with CT scans. To solve this problem, it is necessary to develop a new type of marker that can not only adapt to the needs of motion capture systems, but also provide high contrast and accurate three-dimensional positioning capabilities in CT scans. Summary of the invention

[0009] In order to overcome the limitations of the above-mentioned traditional dynamic capture (motion capture) markers in CT scanning, the present invention has developed a new type of dynamic capture marker, which is made of high-density material and can not only be accurately recognized by the camera in the dynamic capture system, but also be clearly visible in the CT scan. This innovative design allows a seamless correction and integration process to be established between dynamic capture and CT imaging, thereby greatly improving the accuracy of the data and the flexibility of application. Specifically, the invention will promote the integration of patient dynamic data and internal structure images in the field of medical imaging, improve the application quality of motion capture in film and video game development, and achieve more accurate motion analysis and simulation in biomechanical research. By providing a marker that can be recognized by both a dynamic capture camera and a CT scanner, the present invention aims to promote the integration and development of interdisciplinary technologies and bring unprecedented collaboration and research opportunities to related fields.

[0010] The present invention provides a new type of marking point, the density of the new type of marking point is 0.0014-0.0015g / mm 3 ; The new marking point housing is coated with 50-200 micron infrared high reflective material.

[0011] Furthermore, the novel marking point is made of high-density material and plastic material.

[0012] Furthermore, the high-density material includes iridium, tungsten, gold or calcium carbonate.

[0013] Furthermore, the plastic material includes one or more of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polycarbonate (PC), and acrylonitrile-styrene-butadiene copolymer (ABS).

[0014] Furthermore, the infrared high reflective material is nano iron oxide.

[0015] Furthermore, the coating thickness of the infrared high reflective material is 50-200 microns.

[0016] Furthermore, the novel marking point is spherical, hemispherical, cubic or irregularly shaped.

[0017] Furthermore, the plane size of the novel marking point is 3-10 mm×3-10 mm.

[0018] Furthermore, the surface of the novel marking point is a smooth surface, or a surface provided with grooves, grids or polyhedron structures.

[0019] The application of the novel marker points provided by the present invention in the field of CT scanning and / or dynamic capture.

[0020] The present invention also provides a novel marking point that can be used for dynamic capture and / or CT scanning, wherein the density of the novel marking point is 0.0014-0.0015 g / mm 3 ; The new marking point housing is coated with 50-500 micron infrared high reflective material.

[0021] Furthermore, the novel marking point is made of high-density material and plastic material.

[0022] Furthermore, the high-density material includes iridium, tungsten, gold or calcium carbonate.

[0023] Furthermore, the plastic material includes one or more of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polycarbonate (PC), and acrylonitrile-styrene-butadiene copolymer (ABS).

[0024] Furthermore, the infrared high reflective material is nano iron oxide.

[0025] Furthermore, the coating thickness of the infrared high reflective material is 50-200 microns.

[0026] Furthermore, the novel marking point is spherical, hemispherical, cubic or irregularly shaped.

[0027] Furthermore, the plane size of the novel marking point is 3-10 mm×3-10 mm.

[0028] Furthermore, the surface of the novel marking point is a smooth surface, or a surface provided with grooves, grids or polyhedron structures.

[0029] The present invention also provides a method for preparing a novel marking point, wherein the method comprises first mixing a high-density material with a plastic material to prepare the marking point, and then coating the marking point with an infrared high-reflection material to prepare the novel marking point.

[0030] Furthermore, the high-density material has a density of 2.5 to 25 g / cm 3 .

[0031] Furthermore, the high-density material includes iridium, tungsten, gold or calcium carbonate.

[0032] Furthermore, the plastic material includes one or more of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polycarbonate (PC), and acrylonitrile-styrene-butadiene copolymer (ABS).

[0033] Furthermore, the high-density material and the plastic material are mixed to meet the mixed density of 0.0014 to 0.0015 g / mm 3 .

[0034] Furthermore, the infrared high reflective material is nano iron oxide.

[0035] Furthermore, the coating thickness of the infrared high reflective material is 50-500 microns.

[0036] Preferably, the coating thickness of the infrared high reflective material is 50-200 microns.

[0037] Furthermore, the marking point is spherical, hemispherical, cubic or irregular solid.

[0038] Furthermore, the plane size of the marking point is 3-10 mm×3-10 mm.

[0039] Furthermore, the surface of the marking point is a smooth surface, or a surface provided with grooves, grids or polyhedron structures. The design of grooves, grids or polyhedron structures can be used to improve the recognition and positioning accuracy of the marking point.

[0040] The markers produced by the present invention can not only meet the requirements of the optical motion capture system, but also show excellent recognizability in CT imaging. The above functions are achieved by carefully designing the material, shape and density of the markers to ensure that the markers can be accurately identified and tracked in different imaging technologies.

[0041] The new markers designed by the present invention are different from traditional plastic markers. They use high-density materials such as iridium, tungsten, gold, lead, calcium, etc. These materials can provide high contrast in CT scans because they have strong absorption capacity for X-rays. At the same time, these materials can be processed into fine powders or flakes so as to be combined with other materials (such as lightweight plastics or silicone) to maintain the lightness of the markers while maintaining visibility in CT scans.

[0042] Shape Design

[0043] In terms of shape design, the marking points in this patent are not limited to the traditional spherical design (see Figure 1 Considering the three-dimensional imaging characteristics of CT scanning, this patent adopts a polyhedron or a design with specific marks (such as grooves, dot matrix) (a polyhedron design scheme such as Figure 2 , a circular plane cut on the surface), such a shape can produce a unique geometric pattern on the CT image, thereby improving recognition accuracy and positioning accuracy. For example, a spherical marker with several small grooves can provide clear direction indication in the CT image, which helps to accurately align the motion capture data with the CT image.

[0044] Density Adjustment

[0045] In addition, this patent also finely controls the overall density of the marker by adjusting the ratio of high-density materials to other materials inside the marker, so that it can be recognized by the passive capture camera with high reflectivity and exhibit excellent X-ray absorption characteristics in CT scanning. In addition, this design allows the marker to be customized in different application environments, adjusting density and contrast according to specific imaging requirements.

[0046] The beneficial effects of this patent are:

[0047] 1. Enhanced multi-modality imaging compatibility

[0048] The present invention uses high-density materials such as iridium, tungsten, gold or calcium carbonate to prepare a new type of marker point. The contrast of the obtained new marker point in CT scanning is significantly improved, so that it has excellent visibility in X-ray imaging technology. This material selection is not only suitable for traditional optical motion capture systems, but can also be clearly identified in CT imaging, thereby achieving seamless integration of motion capture data and CT images. This cross-modal compatibility is of great significance for applications that require precise matching of dynamic external motion and internal structure (such as medical diagnosis and biomechanical research).

[0049] 2. Improve recognition accuracy and positioning accuracy

[0050] The innovative shape design (such as a polyhedron or a design with specific markers) used in the present invention produces a unique geometric pattern on the CT image, which not only helps to improve the recognition rate of the marker points in the CT scan, but also provides a reliable basis for the precise alignment between the motion capture data and the CT image. Compared with traditional spherical markers, this design provides better direction indication and position information in three-dimensional space, thereby improving the tracking and calibration accuracy of the entire system.

[0051] 3. Flexible application scope and customization capabilities

[0052] The present invention finely controls the overall density and contrast of the marker points by adjusting the ratio of high-density materials to other materials inside the marker points, which not only maintains efficient tracking performance in the optical motion capture system, but also optimizes the X-ray absorption characteristics in CT scanning. This flexible design allows the marker points to be customized according to the specific needs of different applications, increasing their application potential in different fields.

[0053] 4. Promote the integration and development of interdisciplinary technologies

[0054] The new markers in this invention promote the integration of motion capture technology and different disciplines such as CT imaging, bringing new research and application opportunities to multiple fields such as medicine, biomechanics, and film and television production. Especially in research and applications that require simultaneous acquisition of external motion and internal structure information, this integration of technology provides a powerful tool for improving data accuracy and expanding research depth and breadth. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is a schematic diagram of a new type of marking point of the present invention, and its surface is smooth and spherical.

[0056] Figure 2 This is a schematic diagram of a new type of marking point of the present invention, wherein grooves are arranged on the surface of the sphere.

[0057] Figure 3 This is a CT scan image of the new type of marking point obtained in Example 1 of the present invention.

[0058] Figure 4 This is a CT scan image of the new type of marking point obtained in Example 2 of the present invention.

[0059] Figure 5 This is a CT scan image of the new type of marking point obtained in Example 3 of the present invention.

[0060] Figure 6 This is a CT scan image of the new marking point obtained in Example 4 of the present invention.

[0061] Figure 7 This is a CT scan image of the new marking point obtained in Example 5 of the present invention.

[0062] Figure 8 This is an image of the new marking point obtained in Example 2 of the present invention under a visual camera.

[0063] Fig. 9 This is a CT scan image of the new type of marking point obtained in Example 2 of the present invention.

[0064] Fig.10 CT scan image comparison of the novel marking points of Example 1 of the present invention and Comparative Example 1. DETAILED DESCRIPTION

[0065] Example 1

[0066] 30g of calcium carbonate and 70g of polyethylene were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 5mm. Nano-iron oxide with a thickness of 100 microns was then coated on the spherical marker to obtain a new type of marking point.

[0067] The mixed density of the new marking point is 0.001205g / mm 3 , CT scan images such as Figure 3 As shown, the scan result is not clear.

[0068] Example 2

[0069] 40g of calcium carbonate and 60g of polyethylene were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 5mm. Nano-iron oxide with a thickness of 100 microns was then coated on the spherical marker to obtain a new type of marking point.

[0070] The mixed density of the new marking point is 0.001315g / mm 3 , CT scan images such as Figure 4 As shown, the scan results are clear.

[0071] Example 3

[0072] 50g of calcium carbonate and 50g of polyethylene were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 5mm. Nano-iron oxide with a thickness of 100 microns was then coated on the spherical marker to obtain a new type of marking point.

[0073] The mixed density of the new marking point is 0.001448g / mm 3 , CT scan images such as Figure 5 As shown, the scan result is not clear.

[0074] Example 4

[0075] 60g of calcium carbonate and 40g of polyethylene were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 5mm. Nano-iron oxide with a thickness of 100 microns was then coated on the spherical marker to obtain a new type of marking point.

[0076] The mixed density of the new marking point is 0.001611g / mm 3 , CT scan images such as Figure 6 As shown, the scan result is not clear.

[0077] Example 5

[0078] 70g of calcium carbonate and 30g of polyethylene were mixed, melted and squeezed into a mold to make a spherical marker with a diameter of 5mm. Then, nano-iron oxide with a thickness of 100 microns was coated on the spherical marker to make a new type of marking point.

[0079] The mixed density of the new marking point is 0.001816g / mm 3 , CT scan images such as Figure 7 As shown, the scan result is not clear.

[0080] In Examples 1 to 5, the ratio of high-density material to plastic material is increased in a certain proportion gradient, and 10% high-density material is used as an example, from 30% content to 70% content (too high content is not suitable for plastic molding), and 5 kinds of small balls of the same specifications are made by plastic molding process, and CT scanning and identification are performed respectively. The results show that when the high-density material content is about 40% (i.e., the density is 0.001448g / mm 3 The image of the marked point is clearest.

[0081] The usage images and CT scan images of the novel markers of Example 2 are shown in FIG. Figure 8 and Fig. 9 , the CT and motion capture detection results of the new markers of Example 2 are as follows:

[0082] Effect under CT: resolution 1mm, center of mass accuracy 1mm.

[0083] Effect under motion capture camera: resolution 1mm, center of mass accuracy 0.7mm.

[0084] Visual and CT fusion deviation: ±1mm.

[0085] It can be seen that the new type of markers prepared in Example 2 can meet the requirements of motion capture technology and CT imaging, and achieve efficient tracking performance and clear image display.

[0086] Example 6

[0087] 40g of calcium carbonate and 60g of polypropylene were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 6mm. Then, nano-iron oxide with a thickness of 200 microns was coated on the spherical marker to obtain a new type of marking point.

[0088] Example 7

[0089] 40g of calcium carbonate and 60g of acrylonitrile-styrene-butadiene copolymer were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 8mm. Nano-iron oxide with a thickness of 100 microns was then coated on the spherical marker to obtain a new type of marking point.

[0090] Example 8

[0091] 40g of calcium carbonate and 60g of polycarbonate were mixed, melted and squeezed into a mold to obtain a spherical marker with a diameter of 10mm. Nano-iron oxide with a thickness of 150 microns was then coated on the spherical marker to obtain a new type of marking point.

[0092] Example 9

[0093] 40g of calcium carbonate and 60g of polyvinyl chloride were mixed, melted and squeezed into a mold to make a spherical marker with a diameter of 8mm. Then, nano-iron oxide with a thickness of 200 microns was coated on the spherical marker to make a new type of marking point.

[0094] Comparative Example 1

[0095] 40g of calcium carbonate and 60g of polyethylene were mixed, melted and squeezed into a mold to make a spherical marker with a diameter of 15mm, and then nano iron oxide with a thickness of 100 microns was coated on the spherical marker to make a new type of marking point. The new type of marking point prepared above was used for CT detection, and the results were as follows Figure 5 As shown in the figure, the ball in the green frame is Example 1, and the ball in the red frame is Comparative Example 1. It can be seen that the size of the new marking point of the present invention also affects the CT imaging effect of the new marking point, and the CT scanning imaging effect of the overly large spherical marker is not good.

[0096] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. A new type of marking point, characterized in that: The density of the new marking point is 0.0014-0.0015 g / mm 3 ; The new marking point housing is coated with 50-500 micron infrared high reflective material.

2. The novel marking point according to claim 1, characterized in that: The new marking point is made of high-density material and plastic material; the high-density material has a density of 2.5-25g / cm 3 ; The plastic material includes one or more of polyethylene, polypropylene, polyvinyl chloride, polycarbonate, and acrylonitrile-styrene-butadiene copolymer.

3. The novel marking point according to claim 1, characterized in that: The infrared high reflective material is nano iron oxide.

4. The novel marking point according to claim 1, characterized in that: The novel marking point is spherical, hemispherical, cubic or irregular solid.

5. The novel marking point according to claim 1, characterized in that: The plane size of the novel marking point is 3-10 mm×3-10 mm.

6. The novel marking point according to claim 1, characterized in that: The surface of the novel marking point is a smooth surface, or a surface provided with grooves, grids or polyhedron structures.

7. Use of the novel marker according to any one of claims 1 to 6 in the field of CT scanning and / or dynamic capture.

8. The method for preparing a novel marking point according to any one of claims 1 to 6, characterized in that: The preparation method comprises first mixing a high-density material with a plastic material, and after mixing, the mixed density is 0.0014 to 0.0015 g / mm 3 , obtain a marking point, and then coat the marking point with an infrared high-reflective material to obtain a new type of marking point.

9. The preparation method according to claim 8, characterized in that: High-density materials have a density of 2.5 to 25 g / cm 3 ; The plastic material includes one or more of polyethylene, polypropylene, polyvinyl chloride, polycarbonate, and acrylonitrile-styrene-butadiene copolymer.

10. The preparation method according to claim 8, characterized in that: The coating thickness of the infrared high reflective material is 50-500 microns.

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