A marker point setting device, a repeated positioning system and a method for motion capture

Abstract

The present invention relates to a marker point setting device for motion capture, comprising a capture point setting base surface and a marker recognition device; the capture point setting base surface can be closely attached to the object to be measured, and one side thereof is an adhesive surface for adhering to the object to be measured; on the other surface of the capture point setting base surface, there are position identifiers, and the position identifiers are scale line grids formed by vertically and horizontally intersecting scale lines provided on the capture point setting base surface; the present invention also relates to a repeated positioning system and an execution method thereof, comprising a marker point setting device, a positioning recording device, a positioning identifier device, and a measurement placement area; the measurement placement area is used to fix the position of the object to be measured, the positioning identifier device is used to mark the position information of the marker point setting device on the positioning recording device, and the measurement placement area is located between the marker point setting device and the positioning recording device; the advantages are as follows: it can support the free setting of marker points, and can identify the relative positions of marker points, which is beneficial to repeated positioning.

Description

Technical Field

[0001] The present invention relates to the technical field of motion capture, and more specifically, to a marker point setting device, a repeated positioning system and a method for motion capture. Background Art

[0002] The motion capture system is an important means for kinematic analysis. It records the human body surface skin marker recognition device through a motion capture device to obtain the three-dimensional motion state. Through the marker recognition device on the body surface skin, the motion trajectories of key points on the body surface in three-dimensional space are recorded, so as to analyze the human motion pattern. During the use of the motion capture system, it is necessary to fix the marker recognition device on the human body surface. The fixation of the marker recognition device for key points on the body surface is the key point of motion capture technology. At present, the fixation methods of the body surface marker recognition device are mainly divided into two types: traditional direct pasting and fixation with the help of wearable devices.

[0003] In the traditional method of fixing key points on the body surface, the marker recognition device is directly pasted on the body surface, which requires researchers to paste points one by one, increasing the workload of the researchers. In addition, during the motion capture acquisition process, phenomena such as loosening, falling off, and relative skin displacement of the marker recognition device may occur, resulting in a decrease in experimental accuracy. At the same time, when conducting multiple experimental acquisitions on the same user, it is necessary to repeat the pasting of points. The traditional pasting method uses palpation to paste points or uses ultrasonic scanning of bony structures to paste points. During the process of multiple repeated experiments, the repeatability of pasting points is low, and the data error between the two acquisitions before and after is large.

[0004] In the existing technology, the purpose of quickly setting body surface markers is achieved by wearing a tight-fitting garment or a body surface wearable device fixed with a marker recognition device. However, the tight-fitting garment or the body surface wearable device has many inevitable drawbacks. (1) When people are already wearing clothes, operations such as taking off and changing clothes are required, and the process is relatively cumbersome and wastes a lot of time; (2) The tight-fitting garment is not suitable for users of all body types, and there will be a large individual difference in the relative position between the body surface marker recognition device and body surface joint points such as bony structures; (3) During the motion capture process, the marker recognition device will slide together with the tight-fitting garment or the wearable device during the motion, and there will be a large relative displacement between the points captured by the motion capture and the skin sliding, resulting in a large error.

[0005] Chinese Patent Application: CN212394894U discloses a respiratory movement measurement device, which includes: a plurality of marker points, a marker point position change capture unit, and a respiratory movement calculation unit; the plurality of marker points are arranged on the body surface of a subject; the marker point position change capture unit is used to capture the position changes of the plurality of marker points during the subject's breathing process; the respiratory movement calculation unit is used to calculate the respiratory movement condition of the subject according to the position changes of the plurality of marker points during the subject's breathing process. The marker points described therein are arranged on an elastic vest, and the subject wears the vest for measurement; there are multiple rows and multiple marker points distributed on the vest, and the points in each row are on the front side of the vest or around the vest for one week. The marker points can be arranged at positions close to the neck, upper chest, abdomen, and lower abdomen of the vest according to monitoring needs, in multiple rows, and each row can include multiple marker points. Each marker point can reflect the amplitude change of the chest and abdomen contour caused by respiratory movement. This patent arranges the marker points on the vest and then realizes the undulation with the chest cavity through the elasticity of the vest; however, first, it lacks positioning ability. Although the marker points are fixed on the vest, it cannot ensure that the positions are the same as the previous time when worn again, and it is not universal for people with different body types; second, the positions of the marker points cannot be freely set, and it cannot cope with the motion capture of specific positions required for kinematic analysis. For example, after different people wear the vest with marker points, the positions of the marker points relative to the internal organs and bones of the individual are different, and the marker points do not have the ability to be adjusted.

[0006] In summary, there is an urgent need for a marker point setting device, a repeated positioning system and method for motion capture that can support the free setting of marker points, can identify the relative positions of marker points, and facilitate repeated positioning. Summary of the Invention

[0007] The object of the present invention is to provide a marker point setting device for motion capture that can support the free setting of marker points, can identify the relative positions of marker points, and is conducive to repeated positioning.

[0008] To achieve the above object, the technical solution adopted by the present invention is:

[0009] A marker point setting device for motion capture includes a capture point setting base surface; position identifiers are provided on the capture point setting base surface for identifying the relative positions of objects on the capture point setting base surface.

[0010] As a preferred technical solution, the capture point setting base surface is a complete surface, the position identifiers on it are relatively fixed, and the whole of the capture point setting base surface is detachably installed with the object to be measured.

[0011] As a preferred technical solution, the bottom surface of the base surface for setting the capture points is the adhesive surface, wherein the adhesive surface is detachably connected to the base surface for setting the capture points.

[0012] As a preferred technical solution, the position identifier is a scale line grid or uniformly distributed scale points.

[0013] As a preferred technical solution, a marker recognition device is detachably arranged on the base surface for setting the capture points. The bottom of the marker recognition device is provided with a pasting part for detachably connecting to the base surface for setting the capture points. The pasting part is detachably connected to the marker recognition device.

[0014] As a preferred technical solution, a sliding track is arranged on the base surface for setting the capture points, and the sliding track is movably connected to the marker recognition device.

[0015] As a preferred technical solution, a sliding card is arranged on the sliding track, and a fixed card adapted to the sliding card is arranged at the bottom of the marker recognition device. The fixed card and the sliding card are detachably connected; or the bottom of the marker recognition device can also be directly connected to the sliding track.

[0016] Another object of the present invention is to provide a repositioning system that facilitates repeated positioning.

[0017] To achieve the above object, the technical solution adopted by the present invention is:

[0018] A repositioning system for motion capture, comprising: the above-mentioned marker point setting device, positioning recording device, and positioning identification device; the positioning identification device is used to mark the position information of the marker point setting device on the positioning recording device, and the position information includes height distance and width distance.

[0019] As a preferred technical solution, the positioning recording device is a fixed plate provided with scale marks for identifying the relative position marked by the positioning identification device; the positioning identification device is a laser emitter arranged on a launch rack, and a measurement area to be placed is provided between the positioning recording device and the positioning identification device for fixing the position of the object to be measured; a plurality of positioning through holes are arranged on the base surface for setting the capture points of the marker point setting device.

[0020] Another object of the present invention is to provide a repositioning method for motion capture.

[0021] To achieve the above object, the technical solution adopted by the present invention is:

[0022] A repetitive positioning method for motion capture, and a repetitive positioning system for motion capture executes the repetitive positioning method; the repetitive positioning method includes the following steps: obtaining initial position information of a capture plane, wherein the sagittal plane position thereof is kept fixed, and collecting coronal plane position information thereof; outputting the initial position information of the capture plane, and performing repetitive capture positioning.

[0023] The advantages of the present invention are as follows:

[0024] 1. The marker point setting device for motion capture according to the present invention includes a capture point setting base surface and a marker recognition device; the capture point setting base surface is provided with position identifiers thereon, which can be read to record the relative position of the marker recognition device on the capture point setting base surface, avoiding the problem of inconsistent position placement of the marker recognition device during front and back positioning in repetitive positioning, and the marker recognition device can be flexibly set without affecting its flexibility.

[0025] 2. The capture point setting base surface of the marker point setting device for motion capture according to the present invention is a complete surface, and the position identifiers thereon are relatively fixed; firstly, it can ensure that the relative positions of the position identifiers are certain before and after repetitive positioning, so as to avoid the deviation of the actual installation position of the marker recognition device; secondly, the capture point setting base surface is detachably installed with the object to be measured as a whole, the positioning is simple and convenient, and the positioning area is large, and there are many available reference objects, increasing its reliability.

[0026] 3. The bottom surface of the capture point setting base surface is an adhesive surface; the adhesive surface can be completely attached to the object to be measured, which can provide a stable measurement environment, avoiding displacement problems caused by relative movement between clothing and skin during wearable clothing marking, and solving the problems of clothing wearing and fitting; the adhesive surface is detachably connected to the capture point setting base surface, enabling the capture point setting base surface to be reused and reducing the use cost.

[0027] 4. The position identifiers on the capture point setting base surface are scale line grids or evenly distributed scale points; the scale line grids can identify the position of the marker recognition device through the crisscross scale lines; the evenly distributed scale points can also record the position by recording the points set by the marker recognition device.

[0028] 5. The bottom of the marker recognition device is provided with a paste portion, and the paste portion is used for detachably connecting to the capture point setting base surface, which is convenient to operate and use; the paste portion is detachably connected to the marker recognition device, enabling the marker recognition device to be reused and reducing the use cost.

[0029] 6. The base surface where the capture points are set is provided with sliding tracks, and the sliding tracks are movably connected to the marker recognition device. This provides another implementation method, which does not require the use of adhesive to install the marker recognition device and can also provide sufficient flexibility and position recording function.

[0030] 7. The sliding tracks are provided with sliding cards, and the bottom of the marker recognition device is provided with fixed cards adapted to the sliding cards. The fixed cards and the sliding cards are detachably connected, which ensures the flexibility in the number of marker recognition devices set; the bottom of the marker recognition device can also be directly connected to the sliding tracks, providing an implementation method of directly clamping the marker recognition device to the sliding tracks without additional clamping structures.

[0031] 8. The repeated positioning system for motion capture of the present invention includes: the marker point setting device, the positioning and recording device, and the positioning and marking device; the positioning and marking device is used to mark the position information of the marker point setting device on the positioning and recording device, and the position information includes height distance and width distance; it can record the spatial position information occupied by the marker point setting device in the motion capture system, so that it can ensure that the spatial position in the subsequent capture is the same as that in the previous capture during repeated positioning capture.

[0032] 9. The capture point setting base surface of the marker point setting device is provided with a number of positioning through holes, which can be used for auxiliary positioning of the position of the marker point setting device. For example, after irradiating several positioning through holes on it with laser, the overall position and shape can be positioned by using these hole positions.

[0033] 10. The positioning and recording device is a fixed plate provided with scale markings, and the scale markings are used to identify the relative positions marked by the positioning and marking device; the positioning and marking device is a laser emitter arranged on the launch rack, and the position of the launch rack can be adjusted. There is a to-be-measured placement area between the positioning and recording device and the positioning and marking device, and the to-be-measured placement area is used to fix the position of the object to be measured; it provides an application method of the repeated positioning system, and the to-be-measured placement area can fix the position of the object to be measured, so that the position of the capture point setting base surface relative to the object to be measured can be further assisted in positioning by using the repeated positioning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. Figure 1 is a schematic diagram of a marker point setting device for motion capture according to the present invention.

[0035] FIG. Figure 2 is a schematic diagram of a partial view of the capture point setting base surface and the marker recognition device according to the present invention.

[0036] FIG. Figure 3It is another schematic diagram of the position identification of a marker point setting device for motion capture according to the present invention.

[0037] Appendix Figure 4 It is a schematic diagram of another marker point setting device for motion capture according to the present invention.

[0038] Appendix Figure 5 It is appendix Figure 4 The partial enlarged view of

[0039] Appendix Figure 6 It is a schematic diagram of the loading and unloading engagement of the marker recognition device of another marker point setting device for motion capture according to the present invention.

[0040] Appendix Figure 7 It is a schematic diagram of a repeat positioning system for motion capture according to the present invention.

[0041] Appendix Figure 8 It is a schematic diagram of the positioning identification device of a repeat positioning system for motion capture according to the present invention.

[0042] Appendix Figure 9 It is a schematic diagram of the area to be measured and placed of a repeat positioning system for motion capture according to the present invention. Specific embodiments

[0043] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content recorded in the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0044] The reference numerals and components involved in the drawings are as follows:

[0045] 1. Capture point setting base surface 2. Marker recognition device 3. Positioning recording device

[0046] 4. Positioning identification device 5. Area to be measured and placed 11. Position identification

[0047] 12. Sliding track 21. Adhesive part 22. Fixed clamp

[0048] 31. Scale identification 32. Fixed plate 41. Launch rack

[0049] 42. Laser emitter 51. Plantar depression 52. Heel baffle

[0050] 121. Sliding clamp 13. Adhesive surface 14. Positioning through hole

[0051] Embodiment 1

[0052] Please refer to the appendix Figure 1 The appendix Figure 1 is a schematic diagram of a marker point setting device for motion capture according to the present invention. A marker point setting device for motion capture includes a capture point setting base surface 1 and a marker recognition device 2;

[0053] The capture point setting base surface 1 is a complete plane, rectangular in shape, and made of a soft material that can deform and can be closely attached to the object to be measured. In some embodiments, its shape can also be triangular, etc., and a unified fitting system can be set according to the characteristics and needs of the object to be measured. Please refer to the appendix Figure 2 The appendix Figure 2 is a schematic diagram of a part of the capture point setting base surface and the marker recognition device according to the present invention; one side of the capture point setting base surface 1 is an adhesive surface 13, that is, an adhesive is provided on one side for sticking and attaching to the object to be measured. Preferably, the adhesive surface 13 can be an independent structure, that is, a double-sided tape-like structure with adhesives on both sides. One side is attached to the capture point setting base surface 1, and the other side is used for attaching to the object to be measured. Its advantage is that the capture point setting base surface 1 has reusability and relatively reduces the use cost. It should be noted that since the capture point setting base surface 1 in this embodiment is only used as a carrier for the basic position identifier 11, its structure can be a transparent film material, etc., so its cost itself is not high, and disposable capture point setting bases 1 of the same standard can be mass-produced. Another side of the capture point setting base surface 1 is provided with a position identifier 11, and the position identifier 11 is a scale line grid formed by vertically and horizontally intersecting scale lines provided on the capture point setting base surface 1; Please refer to the appendix Figure 3 The appendix Figure 3 is another schematic diagram of the position identifier of a marker point setting device for motion capture according to the present invention; In some embodiments, it can also be scale points evenly distributed on the capture point setting base surface 1, and its position is recorded by recording the points covered by the recognition device.

[0054] Please refer to the appendix again Figure 2 ; The marker recognition device 2 is a marker ball used for camera capture in motion capture, and it is detachably connected to the capture point setting base surface 1. Correspondingly, a paste part 21 is provided at the bottom of the marker recognition device 2 and is adhesively connected to the capture point setting base surface 1, with simple operation and stable connection; Similarly, in order to further reduce its use cost, the paste part 21 is set as an independent double-sided tape-like structure and can be detachably pasted at the bottom of the marker recognition device 2. It should be noted that the detachable connection method between it and the marker recognition device 2 can be realized not only by pasting but also by snap-fastening, and its purpose is to realize the detachable connection between the paste part 21 and the marker recognition device 2.

[0055] It should be noted that when the marker point setting device for motion capture of the present invention is in use, taking easily locatable parts such as the spinous process, scapula and their connecting lines as marks, the capture point setting base surface 1 of the present invention is attached to the surface of the object to be measured, i.e., the human body surface. In this embodiment, taking the back as an example, the capture point setting base surface 1 is pasted on the back through the adhesive surface 13, and then several marker recognition devices 2 are attached to appropriate positions on the capture point setting base surface 1 according to the needs of motion capture, and the positions where the marker recognition devices 2 are located are read and recorded through the position identifier 11. When performing motion capture, since the capture point setting base surface 1 completely coincides with the body surface, the motion information it transmits is the actual motion information, greatly reducing the error source; when performing repeated motion capture on the same person later, only the data stored previously needs to be retrieved, the capture point setting base surface 1 is attached again, and the setting positions of the marker recognition devices 2 are replicated. It should be noted that in order to make the positions where the capture point setting base surfaces 1 are attached before and after the same, corresponding marks can be made on the body surface to mark the position of the capture point setting base surface 1 relative to the body surface, further ensuring the stability of the attachment positions before and after.

[0056] Embodiment 2

[0057] Please refer to the attached Figure 4 、attached Figure 5 ,attached Figure 4 is a schematic diagram of another marker point setting device for motion capture of the present invention; attached Figure 5 is Figure 4 's partial enlarged view. This embodiment is basically the same as Embodiment 1, the difference being that the capture point setting base surface 1 is provided with sliding tracks 12 thereon, and the sliding tracks 12 are arranged vertically and horizontally on the capture point setting base surface 1. Attached Figure 4 、 5 only schematically shows the same-direction sliding tracks, which also have corresponding functions, and the marker recognition device 2 can move and be fixed along the sliding tracks 12; please refer to attached Figure 6 ,attached Figure 6 is a schematic diagram of the loading and unloading engagement of the marker recognition device of another marker point setting device for motion capture of the present invention. To facilitate the disassembly of the marker recognition device 2, several sliding cards 121 are provided on the sliding tracks 12, and a fixed card 22 adapted to the sliding cards 121 is provided at the bottom of the marker recognition device 2, and the fixed card 22 and the sliding cards 121 are detachably connected.

[0058] Embodiment 3

[0059] Please refer to attached Figure 7 ,attached Figure 7Schematic diagram of a repetitive positioning system for motion capture according to the present invention; a repetitive positioning system for motion capture, comprising: a marker point setting device, a positioning recording device 3, a positioning identification device 4, and further comprising a to-be-tested placement area 5; the to-be-tested placement area 5 is used to fix the position of the object to be tested, the positioning identification device 4 is used to mark the position information of the marker point setting device on the positioning recording device 3, and the position information includes height distance and width distance. Among them, the to-be-tested placement area 5 is located between the marker point setting device and the positioning recording device 3;

[0060] The positioning recording device 3 is a fixed plate 32 provided with scale markings 31; the positioning identification device 4 is a laser emitter 42 provided on a launch rack 41; that is, in this embodiment, on the same horizontal plane, there is a fixed plate 32 with criss-cross scale lines, and a launch rack 41 is provided at one end. Please refer to the appendix Figure 8 , appendix Figure 8 Schematic diagram of the positioning identification device of a repetitive positioning system for motion capture according to the present invention; the launch rack 41 has a telescopic function, and a plurality of laser emitters 42 that are translationally and movably connected thereto are provided thereon. The beam of the laser emitter 42 is perpendicularly irradiated on the scale markings 31 of the fixed plate 32. The to-be-tested placement area 5 is provided on the midline between the launch rack 41 and the fixed plate 32, and it is a square area. Please refer to the appendix Figure 9 , appendix Figure 9 Schematic diagram of the to-be-tested placement area of a repetitive positioning system for motion capture according to the present invention; preferably, depressions adapted to the shape of the sole can be provided thereon for the user to position. Even a heel baffle 52 can be provided so that when standing, with the heel touching the baffle as a reference, combined with the sole depression 51, the initial positioning of the human body can be carried out, and the problem of the mismatch between the foot and the size of the sole depression can also be addressed.

[0061] When the repeat positioning system is in operation, first, a person stands at a predetermined position in the to-be-measured placement area 5. As described in the above embodiments, the capture point setting base surface 1 is placed. Before motion capture, the positioning identification device 4 is used to record the spatial position information of the capture point setting base surface 1. Specifically, the laser emitter 42 is turned on, and the emitter bracket 41 is translated up, down, left, and right to make the laser irradiate the corners and / or edges of the capture point setting base surface 1. The position of the laser emitter 42 is fixed, and the initial motion capture is performed. Its advantages are as follows: First, the light spot formed by the laser emitter 42 on the positioning recording device 3 reflects the spatial information of the height and width of the capture point setting base surface 1 in the coronal plane, while the human body and the to-be-measured placement area 5 provide the depth information in the sagittal plane. Therefore, obtaining the relevant parameters enables the construction of the same spatial position as the initial motion capture in subsequent repeat positioning. Second, the marker point setting device solves the problem of repeat positioning of the capture point setting base surface 1 and the marker recognition device 2, and the positioning identification device 4 can use the laser beam to adjust the body position consistency of the human body during repeated capture with that during the initial capture, that is, adjust the standing position to make the positioning points of the capture point setting base surface 1 overlap with the laser path, and repeat positioning can be completed.

[0062] Preferably, in order to make the positioning identification more explicit, a plurality of positioning through holes 14 are provided on the capture point setting base surface 1 of the marker point setting device, that is, the laser beam irradiates the positioning through holes to complete the positioning and recording of spatial information, avoiding errors that may be caused by identifying the edges and corners of the capture point setting base surface 1.

[0063] Embodiment 4

[0064] A repeat positioning method for motion capture, and the repeat positioning system for motion capture according to the present invention executes the following repeat positioning method; it at least includes the following steps S10-20:

[0065] Step S10: Obtain the initial position information of the capture surface. Among them, keep its sagittal plane position fixed and collect its coronal plane position information;

[0066] Keep the sagittal plane depth information of the measured person fixed through the to-be-measured placement area, collect the coronal plane position information of the capture point setting base surface through the positioning identification device, and record this information through the positioning recording device.

[0067] Step S20: Output the initial position information of the capture surface and perform repeat capture positioning.

[0068] Make the subject stand in the placement area to be tested during the initial motion capture, keep the sagittal plane depth information consistent with the initial positioning, use the positioning recording device to reproduce the data measured during the initial positioning, and then set the base surface of the capture point at the same position on the subject's body to align with the reproduced initial measurement data, so that the position of the re-positioning can be overlapped with the position of the initial positioning.

[0069] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the principle of the present invention. These improvements and supplements should also be regarded as the scope of protection of the present invention.

Claims

1. A repetitive positioning system for motion capture, characterized in that, Including: A marker point setting device, a positioning and recording device, and a positioning identification device for motion capture; the positioning identification device is used to mark the position information of the marker point setting device on the positioning and recording device, and the position information includes height distance and width distance. The marker point setting device for motion capture includes a capture point setting base surface; the capture point setting base surface is provided with position markings for identifying the relative positions of objects on the capture point setting base surface. The capture point setting base surface is a complete surface, rectangular in shape, and made of a soft material that can deform. The position markings on the capture point setting base surface are relatively fixed. The capture point setting base surface is detachably installed as a whole with the object to be measured. The bottom surface of the capture point setting base surface is an adhesive surface. Among them, the adhesive surface is detachably connected to the capture point setting base surface. The positioning and recording device is a fixed plate provided with scale markings, and the scale markings are used to identify the relative positions marked by the positioning identification device; the positioning identification device is a laser emitter installed on a launch rack. There is a measurement placement area between the positioning and recording device and the positioning identification device, and the measurement placement area is used to fix the position of the object to be measured; the marker point setting device is provided with a number of positioning through holes on its capture point setting base surface, and a marker identification device is detachably arranged on the capture point setting base surface.

2. The repetitive positioning system for motion capture according to claim 1, wherein The position markings are scale line grids or uniformly distributed scale points.

3. The repetitive positioning system for motion capture according to claim 1, characterized in that, The bottom of the marker identification device is provided with an adhesive part, and the adhesive part is used to be adhesively connected to the capture point setting base surface. Among them, the adhesive part is detachably connected to the marker identification device.

4. The repetitive positioning system for motion capture according to claim 1, wherein The capture point setting base surface is provided with a sliding track, and the sliding track is movably connected to the marker identification device.

5. The repetitive positioning system for motion capture according to claim 4, characterized in that, The sliding track is provided with a sliding card, and the bottom of the marker identification device is provided with a fixed card adapted to the sliding card, and the fixed card is detachably connected to the sliding card; or the bottom of the marker identification device can also be directly connected to the sliding track.

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