Clothing pressure measuring device, human biomechanical model modeling method and system

Abstract

The present invention relates to a clothing pressure measuring device, a human biomechanical model modeling method and a system, wherein the clothing pressure measuring device includes a fixed frame, a plurality of high-definition cameras, a plurality of force sensors and a pressing plate; the plurality of high-definition cameras and the plurality of force sensors are installed on the fixed frame at intervals; an adjustable telescopic rod is fixedly connected between the force sensor and the plurality of pressing plates; when the three-dimensional shape obtained after the pressing plate acts on a human body part not wearing tights to produce deformation is the same as the preset three-dimensional shape, the force sensor outputs a pressure value, and the pressure value is the pressure exerted by the tights on the human body. Based on the clothing pressure measuring device, the pressure value exerted by the tights on the human body surface when the human body is wearing tights can be accurately measured. In addition, based on the pressure value and the deformation of the human body surface, a finite element model is introduced to accurately construct a biomechanical model of the human body part to be measured.

Description

Technical Field

[0001] The present invention relates to the technical field of clothing intelligent engineering, and in particular to a clothing pressure measuring device, a human body biomechanical model modeling method and a system. Background Art

[0002] Sportswear plays an important role in sports activities. Reasonable sportswear can provide different pressures to different parts of the human body during exercise, which can effectively promote the performance of sports movements, thereby improving the effect of sports and protecting the health of athletes. With the development of my country's economy and society and the improvement of people's material and spiritual civilization, there are more and more sports competitions such as skating and cycling, which are increasingly closely related to people's daily lives. This type of sports has gradually become an important project for youth sports training. Athletes' requirements for clothing during exercise have also changed from a single style in the past to multiple types, styles, and customization. At the same time, the clothing is required to have good functionality and comfort. Therefore, modern sportswear needs to meet the needs of sports events for movements, styles, fabrics, and versions according to different athlete body shapes and sports characteristics, and needs to achieve large-scale personalized customization of sportswear.

[0003] Large-scale personalized customization of sportswear is a specific task, which has relatively high requirements for the pattern making of clothing. When tight sportswear is required to meet a certain pressure at a specific position of the human body, the production requirements for the clothing pattern will be further increased. The pressure exerted by the clothing on the human body surface is generated by the elastic contraction of the tight clothing. Accurate measurement of the pressure exerted by clothing on the human body surface and biomechanical modeling simulation have always been a difficult task, and it is difficult to accurately measure and estimate the mechanical and physical properties of the finite element model. In view of this problem, the present invention proposes a clothing pressure measurement device, a human biomechanical model modeling method and a system. Summary of the invention

[0004] The purpose of the present invention is to provide a clothing pressure measurement device, a human biomechanical model modeling method and a system, which can accurately measure the pressure of clothing acting on the human body surface, introduce a finite element model based on the pressure value combined with the deformation of the clothing when it acts on the human body surface, and accurately construct a biomechanical model of the human body part to be measured.

[0005] To achieve the above-mentioned object, the present invention provides a clothing pressure measurement device, comprising a fixed frame, a plurality of high-definition cameras, a plurality of force sensors and a pressing sheet;

[0006] A plurality of the high-definition cameras are fixed on the fixed frame at intervals;

[0007] A plurality of the force sensors are fixed at intervals on the inner side of the fixed frame; an adjustable telescopic rod is fixedly connected between the force sensors and the plurality of pressing sheets.

[0008] A plurality of the pressing sheets act on the surface of the part to be tested of the human body not wearing tights;

[0009] The force sensor is used to output a pressure value when the three-dimensional shape of the part to be measured obtained after the pressure plate acts on the part to be measured of the human body without wearing tights to cause deformation is the same as the preset three-dimensional shape. The pressure value is the pressure exerted by the tights on the human body; the preset three-dimensional shape is the three-dimensional shape of the part to be measured when the human body is wearing tights.

[0010] Optionally, the pressing sheet is vertically connected to the adjustable telescopic rod, and the curvature of the inner surface of the pressing sheet is the same as the curvature of the human body surface;

[0011] The number of the pressing plates is determined according to the position and circumference of the part of the human body to be measured, and the number of the force sensors is the same as the number of the pressing plates.

[0012] Optionally, when the adjustable telescopic rod is extended to its maximum length, the area enclosed by all the pressing plates is smaller than the minimum area of ​​the horizontal cross-section of a human body part; when the adjustable telescopic rod is retracted to its maximum length, the area enclosed by all the pressing plates is larger than the maximum area of ​​the horizontal cross-section of a human body part.

[0013] Optionally, the fixed frame includes a first fixed frame and a second fixed frame, the diameter of the second fixed frame is smaller than the diameter of the first fixed frame, and the first fixed frame and the second fixed frame are concentrically arranged;

[0014] A plurality of the high-definition cameras are installed at equal intervals on the first fixed frame, and a plurality of the force sensors are installed at equal intervals on the inner side of the second fixed frame.

[0015] Optionally, a support frame is fixedly connected to the first fixed frame and the second fixed frame, and the length of the support frame is adjustable; the support frame is fixedly connected to both ends of the diameter of the first fixed frame and both ends of the diameter of the second fixed frame, or the support frame has three connection points with the first fixed frame and the second fixed frame respectively.

[0016] Optionally, a connecting rod is connected between the first fixed frame and the second fixed frame, and a supporting frame is fixedly connected to the first fixed frame or the second fixed frame.

[0017] The support frame is fixedly connected to both ends of the diameter of the first fixed frame or both ends of the diameter of the second fixed frame, or the support frame has three connection points with the first fixed frame or the second fixed frame.

[0018] The present invention also provides a method for constructing a human biomechanical model based on a clothing pressure measurement device, comprising:

[0019] Acquire an initial color image and an initial depth image of the human body to be measured without wearing tights when the value of the force sensor is zero; construct an initial three-dimensional shape of the human body to be measured without wearing tights based on the initial depth image and the initial color image, and construct an initial grid based on the initial three-dimensional shape and the effect of the pressing sheet;

[0020] Obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the part to be tested of the human body not wearing tights to cause deformation after adjusting each adjustable telescopic rod; constructing a deformed three-dimensional shape of the part to be tested of the human body not wearing tights based on the deformed depth image and the deformed color image;

[0021] Determine whether the deformed three-dimensional shape is the same as the three-dimensional shape of the part to be measured of the human body wearing the tights, and obtain a determination result;

[0022] When the judgment result is yes, the deformed three-dimensional shape is the target deformed three-dimensional shape, and the pressure value of the force sensor is read, which is the pressure generated by the tights on the surface of the human body to be tested; when the judgment result is no, return to the step of "obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the human body to be tested without wearing tights after adjusting each adjustable telescopic rod to produce deformation", until the target deformed three-dimensional shape is obtained;

[0023] Constructing a deformed mesh based on the target deformed three-dimensional shape, the action center point of the tabletting, and the topological relationship between the nodes of the initial mesh;

[0024] Based on the initial grid and the deformed grid, the displacement of the action center point of each of the pressing pieces before and after the deformation is obtained;

[0025] Constructing a biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid;

[0026] According to the displacement of the center of action of the pressing plate and the pressure value of each force sensor, the parameters of the biomechanical finite element model of the human body part to be tested are optimized, and the optimized biomechanical finite element model of the human body part to be tested is the biomechanical model of the human body part to be tested; the parameters include the elastic modulus, Poisson's ratio and shear modulus of human muscle and skin tissue.

[0027] Optionally, constructing the initial three-dimensional shape of the part to be measured of the human body not wearing tights based on the initial depth image and the initial color image, and constructing the initial grid based on the initial three-dimensional shape and the action of the pressing sheet specifically includes:

[0028] Obtaining a three-dimensional space point cloud of the part of the human body to be measured that is not wearing tights based on the initial depth image, setting color values ​​for the three-dimensional space point cloud based on pixels of the initial color image to obtain a color three-dimensional space point cloud, and constructing a three-dimensional shape of the part of the human body to be measured that is not wearing tights based on the color three-dimensional space point cloud to obtain the initial three-dimensional shape;

[0029] Based on the initial three-dimensional shape, the action center points of the tablets are extracted to form an initial curve, a number of internal nodes are determined in the initial curve, and the internal nodes and the action center points of the tablets are connected to form an initial grid.

[0030] Optionally, constructing the biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid specifically includes:

[0031] On the deformed grid, the center point of action of the pressing plate is defined as the load application node, the applied load value is the pressure value, and several nodes at the center position in the deformed grid are defined as fixed nodes. The fixed nodes are used to simulate the bones of the human body's part to be tested, and the biomechanical finite element model of the human body's part to be tested is obtained based on the load value and displacement of the center point of action of the pressing plate.

[0032] Optionally, the parameters of the biomechanical finite element model are optimized according to the displacement of the action center point of the pressing tablet and the pressure value, so that the optimized biomechanical finite element model is the biomechanical model of the part of the human body to be tested, which specifically includes:

[0033] Determine the range of elastic modulus and Poisson's ratio of human muscle and skin tissue according to empirical values, determine a number of elastic modulus values ​​and a number of Poisson's ratio values ​​according to a set cycle step, determine a number of shear moduli based on the several elastic modulus values ​​and the several Poisson's ratio values, obtain the biomechanical finite element models with a number of different parameter values ​​based on the several elastic modulus values, the several Poisson's ratio values ​​and the several shear modulus values, and calculate the calculated displacement generated by the center of action of each of the pressing tablets for the biomechanical finite element model under each parameter combination in combination with the pressure value;

[0034] Calculating the deviation between each calculated displacement and the corresponding displacement to obtain the cumulative value of the deviation of the action center point of each pressing tablet;

[0035] The parameter combination corresponding to the minimum cumulative value is selected as the optimized parameter of the biomechanical finite element model. The biomechanical finite element model under the optimized parameter combination is the biomechanical model of the part to be tested of the human body.

[0036] The present invention also provides a system for constructing a human biomechanical model, comprising:

[0037] An initial grid construction module is used to obtain an initial color image and an initial depth image of the human body to be tested without wearing tights when the value of the force sensor is zero; construct an initial three-dimensional shape of the human body to be tested without wearing tights based on the initial depth image and the initial color image, and construct an initial grid based on the initial three-dimensional shape and the action of the compression sheet;

[0038] A deformed three-dimensional morphology acquisition module is used to acquire a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the part to be tested of the human body not wearing tights to produce deformation after adjusting each adjustable telescopic rod; and construct a deformed three-dimensional morphology of the part to be tested of the human body not wearing tights based on the deformed depth image and the deformed color image;

[0039] A target deformed three-dimensional shape judgment module is used to judge whether the deformed three-dimensional shape is the same as the three-dimensional shape of the part to be tested of the human body wearing tights, and obtain a judgment result;

[0040] When the judgment result is yes, the deformed three-dimensional shape is the target deformed three-dimensional shape, and the pressure value of the force sensor is read, which is the pressure generated by the tights on the surface of the human body to be tested; when the judgment result is no, return to the step of "obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the human body to be tested without wearing tights after adjusting each adjustable telescopic rod to generate deformation";

[0041] A deformation mesh construction module, used to construct a deformation mesh based on the target deformation three-dimensional form, the action center point of the pressing sheet and the topological relationship between the nodes of the initial mesh;

[0042] A displacement acquisition module, based on the initial grid and the deformed grid, obtains the displacement of the action center point of each of the pressing pieces before and after the deformation;

[0043] A biomechanical finite element model building module, used for building a biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid;

[0044] The biomechanical model construction module is used to optimize the parameters of the biomechanical finite element model of the human body part to be tested according to the displacement of the center of action of the pressing plate and the pressure value of each force sensor, so that the optimized biomechanical finite element model of the human body part to be tested is the biomechanical model of the human body part to be tested; the parameters include the elastic modulus, Poisson's ratio and shear modulus of human muscle and skin tissue.

[0045] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0046] (1) The present invention provides a clothing pressure measurement device, a human biomechanical model modeling method and system, wherein the clothing pressure measurement device includes a fixed frame, a plurality of high-definition cameras, a plurality of force sensors and a pressing plate; a plurality of the high-definition cameras are fixed on the fixed frame at intervals; a plurality of the force sensors are fixed on the inner side of the fixed frame at intervals; an adjustable telescopic rod is fixedly connected between the force sensors and the plurality of pressing plates, and a plurality of the pressing plates act on the surface of the human body to be measured without wearing tights; the force sensor is used to output a pressure value when the three-dimensional shape of the human body to be measured obtained after the pressing plate acts on the human body to be measured without wearing tights to produce deformation is the same as the preset three-dimensional shape, and the pressure value is the pressure exerted by the tights on the human body; the preset three-dimensional shape is the three-dimensional shape of the human body to be measured when the human body wears tights. Based on the clothing pressure measurement device, the pressure value of the tights acting on the human body surface when the human body wears tights can be accurately measured. In addition, based on the pressure value and the deformation of the surface when the clothing acts on the human body, a finite element model is introduced to accurately construct a biomechanical model of the human body to be measured.

[0047] (2) Based on the constructed human biomechanical model, the boundary conditions and clothing design goals are introduced to obtain the stress-strain diagram of the internal tissue of the human body part to be tested. Combined with the pressure conditions on the surface of the human body part to be tested, it can assist in the design of the sports tights pattern. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0049] Figure 1 A schematic structural diagram of a clothing pressure measuring device provided in Example 1 of the present invention;

[0050] Figure 2 A flow chart of a method for modeling a human biomechanical model provided in Example 1 of the present invention;

[0051] Figure 3 A schematic diagram of an initial grid provided in Example 1 of the present invention;

[0052] Figure 4 A schematic diagram of a deformed grid provided in Example 1 of the present invention;

[0053] Figure 5 A schematic diagram of multiple clothing force measuring devices provided in Example 1 of the present invention distributed on different layers of a human body;

[0054] Figure 6 A schematic diagram of a multi-layer three-dimensional finite element mesh provided in Example 1 of the present invention;

[0055] Figure 7 A block diagram of a human biomechanical modeling system provided in Example 2 of the present invention;

[0056] Explanation of symbols:

[0057] 1: fixed frame; 1-1: first fixed frame; 1-2: second fixed frame; 2: high-definition camera; 3: force sensor; 4: adjustable telescopic rod; 5: tablet press. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] The purpose of the present invention is to provide a clothing pressure measurement device, a human biomechanical model modeling method and a system, which can accurately measure the pressure of clothing acting on the human body surface, introduce a finite element model based on the pressure value combined with the deformation of the clothing when it acts on the human body surface, and accurately construct a biomechanical model of the human body part to be measured.

[0060] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] Example 1

[0062] like Figure 1 As shown, this embodiment provides a clothing pressure measurement device, including a fixed frame 1, a plurality of high-definition cameras 2, a plurality of force sensors 3 and a pressing sheet 5;

[0063] Among them, a number of high-definition cameras 2 are fixed on the fixed frame 1 at intervals;

[0064] A plurality of force sensors 3 are fixed at intervals on the inner side of the fixed frame 1; an adjustable telescopic rod 4 is fixedly connected between the force sensors 3 and a plurality of pressing sheets 5.

[0065] A plurality of pressing sheets 5 act on the surface of the part to be tested of the human body not wearing tights;

[0066] The force sensor 3 is used to output a pressure value when the three-dimensional shape of the part to be measured obtained after the pressure plate 5 acts on the part to be measured of the human body without wearing tights to cause deformation is the same as the preset three-dimensional shape. The pressure value is the pressure exerted by the tights on the human body; the preset three-dimensional shape is the three-dimensional shape of the part to be measured when the human body wears tights.

[0067] It should be noted that the preset three-dimensional shape is the three-dimensional shape of the part to be measured when the human body wears a tights. Here, the three-dimensional shape of the part to be measured when the human body wears a tights can be based on a tights that has been designed, and the clothing pressure measuring device is used to measure the pressure of the tights on the surface of the human body when it is deformed, and the comfort of the tights on the human body can be understood based on the pressure value; or the tights may not be designed, and the pressure of the undesigned tights on the surface of the human body is calculated according to the three-dimensional shape that people want after wearing the tights, and the pressure information is used as data support when designing the tights, so as to design a tights that meets the requirements.

[0068] In order to ensure that the structure of the pressure measurement device is simplified, several high-definition cameras 2 and several force sensors 3 can be set on the same fixed frame 1. In order not to affect the functions of the high-definition camera 2 and the force sensor 3, the high-definition camera 2 can be fixed on the outside of the fixed frame 1, and the force sensor 3 can be set on the inside of the fixed frame 1. The fixed frame 1 can be set to be circular, and its diameter can be selected to be 1m. The shape and size of the fixed frame 1 can also be adjusted according to actual needs. In order to be able to more comprehensively understand the deformation of the human body surface and the stress conditions of various parts of the human body surface, it is required that the high-definition camera 2 and the force sensor 3 cover the entire circumference of the fixed frame 1, that is, the high-definition camera 2 and the force sensor 3 are arranged around the fixed frame 1. The number of high-definition cameras 2 and the number of force sensors 3 can be the same or different, but the force sensor 3 and the pressing plate 5 are one-to-one corresponding. Therefore, the number of the pressing plates 5 is determined according to the position and circumference of the part to be measured on the human body. For example, when measuring the pressure of a tights on the surface of the human waist, since the circumference of the waist is large, more pressing plates 5 can be set. The smaller the spacing between the pressing plates 5, the more accurate the simulation of the waist deformation. Then, the value obtained by the force sensor 3 is more accurate. In addition, the spacing between the action centers of the pressing plates 5 can be determined according to the unit specifications of the finite element model, so that when the finite element model is established, the force of each pressing plate 5 is equivalent to the node applied to the finite element. For example, if the specification of the finite element grid division defines a grid with a side length of about 5cm, if the circumference is 60cm, it is determined as 12 pressing plates 5 action points. According to the circumference and grid specifications, a number that is easy to divide equally is taken, such as 12, 16, 18, 24, 32, etc., which is convenient for realizing the symmetry of the finite element grid.

[0069] The high-definition camera 2 can be an RGBD depth camera, or it can be determined according to the needs. The high-definition camera 2 is facing the center point of the fixed frame 1. The force sensor 3 can be a tension pressure sensor with a micro-voltage signal output, and the sensor uses a built-in data acquisition card to collect pressure data. The force sensor 3 can be connected to the telescopic rod by screws, and the connection method can also be selected according to the needs.

[0070] In order to simulate the deformation of the body suit on the human body surface more realistically and ensure the comfort of the pressing sheet 5 when it acts on the human body surface, the curvature of the inner surface of the pressing sheet 5 is required to be the same as that of the human body surface. At the same time, it is easier to control the pressing sheet 5 acting on the human body surface, and the pressing sheet 5 can be vertically connected to the adjustable telescopic rod 4. The shape and size of the pressing sheet 5 can be set to a square unit area of ​​the pressing sheet 5, and the thickness can be selected to be 2mm. The design data of the pressing sheet 5 can also be determined according to actual needs.

[0071] Since the pressure measuring device in this embodiment uses the adjustable telescopic rod 4 to read the pressure value of the force sensor 3 when the surface of each part of the human body is deformed, the pressure measuring device is required to be applicable to each part of the human body. Therefore, when the adjustable telescopic rod 4 is extended to the maximum length, the area surrounded by all the pressing plates 5 is smaller than the minimum area of ​​the horizontal cross section of the human body part; when the adjustable telescopic rod 4 is retracted to the maximum length, the area surrounded by all the pressing plates 5 is larger than the maximum area of ​​the horizontal cross section of the human body part. The adjustable telescopic rod 4 can be adjusted by a screw thread.

[0072] In addition, the high-definition camera 2 and the force sensor 3 can be respectively arranged on different fixed frames 1, and the fixed frame 1 can be required to include a first fixed frame 1-1 and a second fixed frame 1-2, the diameter of the second fixed frame 1-2 is smaller than the diameter of the first fixed frame 1-1, and the first fixed frame 1-1 and the second fixed frame 1-2 are arranged concentrically; in this case, it is required that a number of high-definition cameras 2 are installed at equal intervals on the first fixed frame 1-1, and a number of force sensors 3 are installed at equal intervals on the inner side of the second fixed frame 1-2. In addition, to ensure that the high-definition camera 2 can clearly capture the image of the human body surface, it is required that the distance between the first fixed frame 1-1 and the second fixed frame 1-2 should not be too large.

[0073] Considering the fixing problem of the fixed frame 1, a support frame can be set for the fixed frame 1. For the case including the first fixed frame 1-1 and the second fixed frame 1-2, the first fixed frame 1-1 and the second fixed frame 1-2 can be fixedly connected to the same support frame, and the length of the support frame is adjustable; the support frame is fixedly connected to both ends of the diameter of the first fixed frame 1-1 and the two ends of the diameter of the second fixed frame 1-2, and the support frame has three connection points with the first fixed frame 1-1 and the second fixed frame 1-2 respectively. In addition to the above-mentioned fixing method, a connecting rod can also be connected between the first fixed frame 1-1 and the second fixed frame 1-2, and the support frame is fixedly connected to the first fixed frame 1-1 or the second fixed frame 1-2. The support frame is fixedly connected to both ends of the diameter of the first fixed frame 1-1 or the two ends of the diameter of the second fixed frame 1-2, or the support frame has three connection points with the first fixed frame 1-1 or the second fixed frame 1-2. In order to ensure the stability of the fixed frame, the connection point between the support frame and the fixed frame can be set according to actual needs, and the two connection points and three connection points in this embodiment do not have a limiting effect on the present invention. In addition, the fixed bracket can also be supported by a universal arm.

[0074] In addition, the clothing pressure measuring device in this embodiment can be used alone or in multiples to measure deformation conditions at different positions, depending on actual needs.

[0075] In this embodiment, the clothing pressure measuring device deforms the human body surface by adjusting the adjustable telescopic rod 4. When the deformed three-dimensional shape is the same as the three-dimensional shape of the human body wearing tight clothing, the pressure generated by the tight clothing on the human body surface can be known by reading the pressure value of the force sensor 3. Obviously, based on the ability of the clothing pressure measuring device to accurately measure the pressure of clothing on the human body surface, the comfort of the tight clothing on the human body can be understood based on the pressure value, and the tight clothing pattern can also be adjusted according to the pressure value.

[0076] Example 2

[0077] like Figure 2 As shown, this embodiment provides a method for modeling a human biomechanical model, comprising the following steps:

[0078] S1: obtaining an initial color image and an initial depth image of the human body to be measured without wearing tights when the value of the force sensor is zero; constructing an initial three-dimensional shape of the human body to be measured without wearing tights based on the initial depth image and the initial color image, and constructing an initial grid based on the initial three-dimensional shape and the effect of the pressing sheet;

[0079] First, adjust each adjustable telescopic rod so that when the pressure piece acts on the surface of the part to be measured of the human body that is not wearing tights, the value read from the force sensor is zero; wherein, when the reading of the force sensor is zero or the value fluctuation range is within a certain minimum value range, it is considered that there is no force; when the pressure piece acts on the surface of the part to be measured of the human body that is not wearing tights, it is a contact without force, and the force sensor has a certain reading, the reading of the force sensor can be set to zero, which is convenient for the accuracy of subsequent force measurement.

[0080] Step S1 specifically includes:

[0081] Obtaining a three-dimensional space point cloud of the part of the human body to be measured that is not wearing tights based on the initial depth image, setting color values ​​for the three-dimensional space point cloud based on pixels of the initial color image to obtain a color three-dimensional space point cloud, and constructing a three-dimensional shape of the part of the human body to be measured that is not wearing tights based on the color three-dimensional space point cloud to obtain the initial three-dimensional shape;

[0082] Based on the initial three-dimensional shape, the action center point of the tablet is extracted to form an initial curve, a number of internal nodes are determined in the initial curve, and the internal nodes and the action center points of each tablet are connected to form an initial grid, such as Figure 3 shown.

[0083] Among them, a depth camera is used to obtain a depth image and a color image. The depth camera can use primesense, orbbec, kinect, etc., and the image resolution can be 640*480 pixels; OpenNI is used to convert the depth image into a point cloud in three-dimensional space, and the color image pixels are aligned with the point cloud to set the color value of the point cloud; the color texture information is used to determine the gradient change of the grayscale values ​​of adjacent pixels within a certain range in the image to assist in the positioning of feature points. The point clouds in the images taken by multiple depth cameras are synthesized into the global coordinate system through a fixed coordinate system to form a complete three-dimensional point cloud of the human body surface of the part to be tested. In other words, a global coordinate system is established, and then the transformation matrix (translation matrix, rotation matrix) from the relative coordinate system of each camera to the global coordinate system is calculated, and multiple depth cameras are transformed into the global coordinate system using their own transformation matrices. Multiple three-dimensional point clouds are located in the global coordinate system at the same time and merged into the same model, which is the three-dimensional point cloud of the human body surface of the part to be tested.

[0084] When constructing the initial mesh, the center of action of the pressure sheet is used as the outermost node of the mesh to determine the number of internal nodes, and the selection of the number of internal nodes depends on whether the initial mesh constructed is a triangular mesh or a quadrilateral mesh. In addition, when dividing the mesh, the outermost node can be the same as the pressure point or different, but the number of the outermost nodes of the mesh must be more than the number of the center of action of the pressure sheet, and each center of action of the pressure sheet must correspond to a mesh node.

[0085] S2: Obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the part to be tested of the human body not wearing tights to cause deformation after adjusting each adjustable telescopic rod; constructing a deformed three-dimensional shape of the part to be tested of the human body not wearing tights based on the deformed depth image and the deformed color image;

[0086] When adjusting the telescopic rod, a uniform load is applied, that is, the sensor pressure values ​​at each position are roughly equal, so that a more accurate deformation situation can be obtained. The method for constructing the deformed three-dimensional shape is the same as the method for constructing the initial three-dimensional shape.

[0087] S3: determining whether the deformed three-dimensional shape is the same as the three-dimensional shape of the part to be measured of the human body wearing the tights, and obtaining a determination result;

[0088] When the judgment result is yes, the deformed three-dimensional shape is the target deformed three-dimensional shape, and the pressure value of the force sensor is read, and the pressure value is the pressure generated by the tights on the surface of the human body part to be measured; when the judgment result is no, return to step S2 until the target deformed three-dimensional shape is obtained;

[0089] The target deformed three-dimensional shape is the preset three-dimensional shape (the three-dimensional shape of the part to be measured when the human body wears tights). The data of each force sensor in a stable state is recorded by a multi-channel data acquisition card.

[0090] S4: constructing a deformed mesh based on the target deformed three-dimensional shape, the action center point of the tabletting, and the topological relationship between the nodes of the initial mesh;

[0091] like Figure 4 As shown in the figure, the topological relationship between the nodes in the initial mesh and the deformed mesh remains unchanged, only the coordinates of the nodes in the deformed mesh have changed relative to the initial mesh. Therefore, the method of constructing the deformed mesh is the same as the method of constructing the initial mesh, and will not be repeated here.

[0092] S5: based on the initial grid and the deformed grid, obtaining the displacement of the action center point of each of the pressing pieces before and after the deformation;

[0093] When calculating the displacement of the action center point of each of the pressing sheets before and after deformation, the initial grid and the deformed grid can be mapped to the same coordinate system, so that the displacement change of the outermost grid node before and after deformation can be clearly known.

[0094] S6: constructing a biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid; specifically comprising:

[0095] On the deformed grid, the center point of action of the pressing plate is defined as the load application node, the applied load value is the pressure value, and several nodes at the center position of the deformed grid are defined as fixed nodes, and the fixed nodes are used to simulate the bones of the human body part to be tested. Based on the load value and displacement of the center point of action of the pressing plate, the biomechanical finite element model of the human body part to be tested is obtained. On the basis of the deformed grid, the biomechanical finite element model of the human body part to be tested is obtained based on the load value and displacement of the center point of action of the pressing plate. For a two-dimensional finite element model, both the node load and the displacement are two-dimensional vectors.

[0096] S7: Optimizing the parameters of the biomechanical finite element model of the human body part to be tested according to the displacement of the action center of the pressing sheet and the pressure value of each of the force sensors, and obtaining the optimized biomechanical finite element model of the human body part to be tested, that is, the biomechanical model of the human body part to be tested; the parameters include the elastic modulus, Poisson's ratio and shear modulus of human muscle and skin tissue, specifically including:

[0097] Determine the range of elastic modulus and Poisson's ratio of human muscle and skin tissue according to empirical values, determine a number of elastic modulus values ​​and a number of Poisson's ratio values ​​according to a set cycle step length, determine a number of shear moduli based on the elastic modulus values ​​and the number of Poisson's ratio values ​​(any two values ​​among the known elastic modulus value, Poisson's ratio number and shear modulus can be used to calculate the third quantity according to the relationship between the elastic modulus, Poisson's ratio and shear modulus), obtain the biomechanical finite element models with a number of different parameter values ​​based on the elastic modulus values, the Poisson's ratio values ​​and the shear modulus values, and calculate the calculated displacement generated by the center of action of each of the pressing tablets in combination with the pressure value for the biomechanical finite element model under each parameter combination;

[0098] Calculating the deviation between each calculated displacement and the corresponding displacement to obtain the cumulative value of the deviation of the action center point of each pressing tablet;

[0099] The parameter combination corresponding to the minimum cumulative value is selected as the optimized parameter of the biomechanical finite element model. The biomechanical finite element model under the optimized parameter combination is the biomechanical model of the part to be tested of the human body.

[0100] After obtaining the biomechanical model of the human body part to be tested, for the finite element model that has completed unit division and load and boundary conditions, according to the nodes and unit structures of the model grid division, the elastic modulus E, Poisson's ratio v, and shear modulus G of the human muscle and skin tissue obtained based on experience are taken to calculate the unit stiffness matrix and the total stiffness matrix, and the finite element equation group is constructed according to the total stiffness matrix and the node load to solve the displacement vectors of the nodes in the model except the center point of pressure action and the fixed nodes (regarded as bones);

[0101] The boundary condition refers to setting the corresponding displacement of the point set to be fixed to 0, so that the constructed total stiffness matrix equation group has a solution.

[0102] Therefore, based on the constructed human biomechanical model, the boundary conditions and clothing design goals are introduced to obtain the stress-strain diagram of the internal tissue of the human body to be tested, combined with the pressure conditions on the surface of the human body to be tested, thereby assisting the design of the sports tights pattern.

[0103] It can be seen that the established finite element model can be used to simulate and calculate other load values, realize the finite element modeling and simulation of biomechanics of human body parts, and provide an accurate data source and model support for the research and development of clothing comfort functionality.

[0104] In addition, the theoretical steps of finite element solution of elasticity plane problems are as follows:

[0105] (1) Arrange the original data, discretize the structure, and number the units and nodes;

[0106] (2) Calculate the unit stiffness matrix [k] e ;

[0107] (3) Using the stiffness integration method, the overall stiffness matrix of the structure [K] is formed;

[0108] (4) Calculate the equivalent load of the node and write the load matrix {R};

[0109] (5) Introducing support conditions;

[0110] (6) Solve [K]{d}={R} to find the node displacement {d};

[0111] (7) Calculate unit stress;

[0112] (8) Calculate the unit node force;

[0113] (9) Organize the results and obtain the node displacement diagram and stress diagram.

[0114] It should be noted that multiple clothing pressure measuring devices can be used to synchronously collect pressure data, and multiple clothing force measuring devices are distributed on different layers of the human body, such as Figure 5 As shown, the multiple layers are arranged equidistantly; when multiple clothing pressure measuring devices are set, multiple layers of force sensors can be set, that is, multiple second fixed frames are distributed on different layers of the human body, and one or more first fixed frames can be set on the first fixed frame. A high-definition camera is set on the first frame, and the number of the first fixed frames is set according to demand. As long as the requirements for image acquisition of the human body part to be measured are met, the number of the first fixed frames and the design of the first fixed frames are within the scope of protection of the present invention.

[0115] At this time, a three-dimensional surface model of the outer surface of the human body part to be tested is constructed and discretized into a three-dimensional finite element model, and the nodes of each layer correspond to the force measuring device of the clothing layer. Figure 6 The figure shows a multi-layer three-dimensional finite element mesh, with several nodes in the middle of each layer set as fixed nodes. For the three-dimensional finite element model, the node load and displacement are both three-dimensional vectors. For the calculation of the three-dimensional hexahedral mesh, the formula of three-dimensional hexahedral finite element analysis is used.

[0116] In this embodiment, the clothing pressure measuring device can accurately measure the pressure value of the tights on the surface of the human body when the human body is wearing tights. In addition, based on the pressure value and the deformation of the surface when the clothing acts on the human body, a finite element model is introduced to accurately construct a biomechanical model of the human body part to be tested. And based on the constructed human biomechanical model, the boundary conditions and clothing design goals are introduced to obtain the stress-strain diagram of the internal tissue of the human body part to be tested, and combined with the pressure on the surface of the human body part to be tested, it can assist in the design of the sports tights pattern.

[0117] Example 3

[0118] like Figure 7 As shown, this embodiment provides a system for constructing a human biomechanical model, including:

[0119] An initial grid construction module is used to obtain an initial color image and an initial depth image of the human body to be tested without wearing tights when the value of the force sensor is zero; construct an initial three-dimensional shape of the human body to be tested without wearing tights based on the initial depth image and the initial color image, and construct an initial grid based on the initial three-dimensional shape and the action of the compression sheet;

[0120] A deformed three-dimensional morphology acquisition module is used to acquire a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the part to be tested of the human body not wearing tights to produce deformation after adjusting each adjustable telescopic rod; and construct a deformed three-dimensional morphology of the part to be tested of the human body not wearing tights based on the deformed depth image and the deformed color image;

[0121] A target deformed three-dimensional shape judgment module is used to judge whether the deformed three-dimensional shape is the same as the three-dimensional shape of the part to be tested of the human body wearing tights, and obtain a judgment result;

[0122] When the judgment result is yes, the deformed three-dimensional shape is the target deformed three-dimensional shape, and the pressure value of the force sensor is read, which is the pressure generated by the tights on the surface of the human body to be tested; when the judgment result is no, return to the step of "obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the human body to be tested without wearing tights after adjusting each adjustable telescopic rod to produce deformation", until the target deformed three-dimensional shape is obtained;

[0123] A deformation mesh construction module, used to construct a deformation mesh based on the target deformation three-dimensional form, the action center point of the pressing sheet and the topological relationship between the nodes of the initial mesh;

[0124] A displacement acquisition module, based on the initial grid and the deformed grid, obtains the displacement of the action center point of each of the pressing pieces before and after the deformation;

[0125] A biomechanical finite element model building module, used for building a biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid;

[0126] The biomechanical model construction module is used to optimize the parameters of the biomechanical finite element model of the human body part to be tested according to the displacement of the center of action of the pressing plate and the pressure value of each force sensor, so that the optimized biomechanical finite element model of the human body part to be tested is the biomechanical model of the human body part to be tested; the parameters include the elastic modulus, Poisson's ratio and shear modulus of human muscle and skin tissue.

[0127] The present invention discloses a tight-fitting garment pressure measurement device, a human biomechanical model modeling method and system, which comprehensively integrates intelligent information processing technologies such as three-dimensional depth imaging, machine vision, graphic image processing, and finite element, to realize a garment pressure measurement device, as well as human biomechanical simulation calculation and analysis based on measured data, which is helpful to improve the functionality and comfort of the personalized version of tight-fitting sportswear, while improving the efficiency and accuracy of customized plate making. The present invention can optimize the biomechanical model based on measured data for the target human body, promote the extensive and in-depth application of the new generation of information technology in the field of clothing intelligent manufacturing engineering, and expand the application field of clothing intelligent engineering. Provide new technical means and practical tools for personalized customized intelligent plate making of tight-fitting sportswear, and improve the automation and intelligence level of tight-fitting sportswear design and production.

[0128] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0129] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A clothing pressure measuring device, characterized in that: It includes a fixed frame, several high-definition cameras, several force sensors and a pressing sheet; A plurality of the high-definition cameras are fixed on the fixed frame at intervals; A plurality of the force sensors are fixed at intervals on the inner side of the fixed frame; an adjustable telescopic rod is fixedly connected between the force sensors and the plurality of pressing sheets. A plurality of the pressing sheets act on the surface of the part to be tested of the human body not wearing tights; The force sensor is used to output a pressure value when the three-dimensional shape of the measured part obtained after the pressure sheet acts on the measured part of the human body without tights to cause deformation is the same as the preset three-dimensional shape. The pressure value is the pressure exerted by the tights on the human body; the preset three-dimensional shape is the three-dimensional shape of the measured part when the human body is wearing tights; The pressing sheet is vertically connected to the adjustable telescopic rod, and the curvature of the inner surface of the pressing sheet is the same as the curvature of the human body surface; The number of the pressing plates is determined according to the position and circumference of the part of the human body to be measured, and the number of the force sensors is the same as the number of the pressing plates.

2. The clothing pressure measuring device according to claim 1, characterized in that: When the adjustable telescopic rod is extended to its maximum length, the area enclosed by all the pressing plates is smaller than the minimum area of ​​the horizontal cross-section of the human body part; when the adjustable telescopic rod is retracted to its maximum length, the area enclosed by all the pressing plates is larger than the maximum area of ​​the horizontal cross-section of the human body part.

3. The clothing pressure measuring device according to claim 1, characterized in that: The fixed frame includes a first fixed frame and a second fixed frame, the diameter of the second fixed frame is smaller than the diameter of the first fixed frame, and the first fixed frame and the second fixed frame are arranged concentrically; A plurality of the high-definition cameras are installed at equal intervals on the first fixed frame, and a plurality of the force sensors are installed at equal intervals on the inner side of the second fixed frame.

4. The clothing pressure measuring device according to claim 3, characterized in that: A support frame is fixedly connected to the first fixed frame and the second fixed frame, and the length of the support frame is adjustable; the support frame is fixedly connected to both ends of the diameter of the first fixed frame and both ends of the diameter of the second fixed frame, or the support frame has three connection points with the first fixed frame and the second fixed frame respectively.

5. The clothing pressure measuring device according to claim 3, characterized in that: A connecting rod is connected between the first fixed frame and the second fixed frame, and a supporting frame is fixedly connected to the first fixed frame or the second fixed frame; The support frame is fixedly connected to both ends of the diameter of the first fixed frame or both ends of the diameter of the second fixed frame, or the support frame has three connection points with the first fixed frame or the second fixed frame.

6. A method for constructing a human biomechanical model based on the clothing pressure measurement device according to any one of claims 1 to 5, characterized in that: include: Acquire an initial color image and an initial depth image of the part to be measured of the human body without wearing tights when the value of the force sensor is zero; constructing an initial three-dimensional shape of the part of the human body to be measured without wearing tights based on the initial depth image and the initial color image, and constructing an initial grid based on the initial three-dimensional shape and the effect of the pressing sheet; Obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the to-be-tested part of the human body without wearing tights to deform after adjusting each adjustable telescopic rod; Constructing a deformed three-dimensional shape of the part to be measured of the human body not wearing tights based on the deformed depth image and the deformed color image; Determine whether the deformed three-dimensional shape is the same as the three-dimensional shape of the part to be measured of the human body wearing the tights, and obtain a determination result; When the judgment result is yes, the deformed three-dimensional shape is the target deformed three-dimensional shape, and the pressure value of the force sensor is read, which is the pressure generated by the tights on the surface of the human body to be tested; when the judgment result is no, return to the step of "obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the human body to be tested without wearing tights after adjusting each adjustable telescopic rod to generate deformation", until the target deformed three-dimensional shape is obtained; Constructing a deformed mesh based on the target deformed three-dimensional shape, the action center point of the tabletting, and the topological relationship between the nodes of the initial mesh; Based on the initial grid and the deformed grid, the displacement of the action center point of each of the pressing pieces before and after the deformation is obtained; Constructing a biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid; According to the displacement of the center of action of the pressing plate and the pressure value of each force sensor, the parameters of the biomechanical finite element model of the human body part to be tested are optimized, and the optimized biomechanical finite element model of the human body part to be tested is the biomechanical model of the human body part to be tested; the parameters include the elastic modulus, Poisson's ratio and shear modulus of human muscle and skin tissue.

7. The method for constructing a human biomechanical model according to claim 6, characterized in that: The step of constructing the initial three-dimensional shape of the part of the human body to be measured without wearing tights based on the initial depth image and the initial color image, and constructing the initial grid based on the initial three-dimensional shape and the action of the pressing sheet, specifically includes: Obtaining a three-dimensional space point cloud of the part of the human body to be measured that is not wearing tights based on the initial depth image, setting color values ​​for the three-dimensional space point cloud based on pixels of the initial color image to obtain a color three-dimensional space point cloud, and constructing a three-dimensional shape of the part of the human body to be measured that is not wearing tights based on the color three-dimensional space point cloud to obtain the initial three-dimensional shape; Based on the initial three-dimensional shape, the action center points of the tablets are extracted to form an initial curve, a number of internal nodes are determined in the initial curve, and the internal nodes and the action center points of the tablets are connected to form an initial grid.

8. The method for constructing a human biomechanical model according to claim 6, characterized in that: The step of constructing the biomechanical finite element model of the human body part to be tested without wearing tights based on the deformed grid specifically includes: On the deformed grid, the center point of action of the pressing plate is defined as the load application node, the applied load value is the pressure value, and several nodes at the center position in the deformed grid are defined as fixed nodes. The fixed nodes are used to simulate the bones of the human body's part to be tested, and the biomechanical finite element model of the human body's part to be tested is obtained based on the load value and displacement of the center point of action of the pressing plate.

9. The method for constructing a human biomechanical model according to claim 6, characterized in that: The method of optimizing the parameters of the biomechanical finite element model according to the displacement of the action center point of the pressing tablet and the pressure value, and obtaining the optimized biomechanical finite element model, which is the biomechanical model of the part to be tested of the human body, specifically includes: Determine the range of elastic modulus and Poisson's ratio of human muscle and skin tissue according to empirical values, determine a number of elastic modulus values ​​and a number of Poisson's ratio values ​​according to a set cycle step, determine a number of shear moduli based on the elastic modulus values ​​and the Poisson's ratio values, obtain the biomechanical finite element models with a number of different parameter values ​​based on the elastic modulus values, the Poisson's ratio values ​​and the shear modulus values, and calculate the calculated displacement generated by the center of action of each pressing tablet for the biomechanical finite element model under each parameter combination in combination with the pressure value; Calculating the deviation between each calculated displacement and the corresponding displacement to obtain the cumulative value of the deviation of the action center point of each pressing tablet; The parameter combination corresponding to the minimum cumulative value is selected as the optimized parameter of the biomechanical finite element model. The biomechanical finite element model under the optimized parameter combination is the biomechanical model of the part to be tested of the human body.

10. A system for constructing a human biomechanical model based on the clothing pressure measurement device according to any one of claims 1 to 5, characterized in that: include: An initial mesh building module, used for obtaining an initial color image and an initial depth image of a human body part to be tested without wearing tights when the value of the force sensor is zero; constructing an initial three-dimensional shape of the part of the human body to be measured without wearing tights based on the initial depth image and the initial color image, and constructing an initial grid based on the initial three-dimensional shape and the effect of the pressing sheet; A deformation three-dimensional morphology acquisition module is used to acquire a deformation color image and a deformation depth image when the pressure sheet acts on the surface of the tested part of the human body without tights to deform after adjusting each adjustable telescopic rod; Constructing a deformed three-dimensional shape of the part to be measured of the human body not wearing tights based on the deformed depth image and the deformed color image; A target deformed three-dimensional shape judgment module is used to judge whether the deformed three-dimensional shape is the same as the three-dimensional shape of the part to be tested of the human body wearing tights, and obtain a judgment result; When the judgment result is yes, the deformed three-dimensional shape is the target deformed three-dimensional shape, and the pressure value of the force sensor is read, which is the pressure generated by the tights on the surface of the human body to be tested; when the judgment result is no, return to the step of "obtaining a deformed color image and a deformed depth image when the pressure sheet acts on the surface of the human body to be tested without wearing tights after adjusting each adjustable telescopic rod to generate deformation"; A deformation mesh construction module, used to construct a deformation mesh based on the target deformation three-dimensional form, the action center point of the pressing sheet and the topological relationship between the nodes of the initial mesh; A displacement acquisition module, based on the initial grid and the deformed grid, obtains the displacement of the action center point of each of the pressing pieces before and after the deformation; A biomechanical finite element model building module, used for building a biomechanical finite element model of the human body to be tested without wearing tights based on the deformed grid; The biomechanical model construction module is used to optimize the parameters of the biomechanical finite element model of the human body part to be tested according to the displacement of the center of action of the pressing plate and the pressure value of each force sensor, so that the optimized biomechanical finite element model of the human body part to be tested is the biomechanical model of the human body part to be tested; the parameters include the elastic modulus, Poisson's ratio and shear modulus of human muscle and skin tissue.

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