Spine posture monitoring method and system

Abstract

The invention provides a spine posture monitoring method and system, and the method comprises the steps: detecting a corresponding deformation place when the shape change is detected, obtaining the current wavelength of each fiber bragg grating at the deformation place through a fiber bragg grating demodulator, and constructing a wavelength drift matrix according to the difference value between the current wavelength and the initial wavelength; based on a first preset algorithm, a strain matrix is obtained through calculation of the wavelength drift matrix, and based on a second preset algorithm, the bending curvature and the bending direction correspondingly generated by the three-dimensional shape sensor at the deformation site are deduced through the strain matrix; cubic spline interpolation is carried out on the discrete bending curvature and bending direction, so that the discrete bending curvature and bending direction continuously change in space; and based on a minimum rotation frame of a space three-dimensional curve, calculating a tangent vector of the three-dimensional shape sensor according to the bending curvature and the bending direction after interpolation, and reconstructing a three-dimensional space coordinate of a deformation site through integral iteration, thereby determining the spine posture. The spine monitoring efficiency can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent sensing technology, and in particular to a method and system for monitoring spinal posture. Background Technology

[0002] The spine is the core supporting structure of the human torso, and its posture monitoring is of great value in scenarios such as adolescent development screening, health management of office workers, and postoperative rehabilitation of the spine. Existing monitoring equipment mostly collects the pitch and lateral bending angles of the torso through inertial measurement units and optical sensors, and then uses algorithms to indirectly infer the segmental curvature of the cervical, thoracic, and lumbar vertebrae, which constitutes the mainstream monitoring solution.

[0003] The spine is actually a three-dimensional coupled motion system formed by the connection between the cervical and sacral vertebrae. Its activities include coronal lateral bending, sagittal pitching, and horizontal rotation, which are interconnected to form a complete posture. Existing methods only focus on one or two dimensions of data, which is a simplified treatment of spinal motion. This can easily miss complex postural abnormalities such as rotational deformities and vertebral slippage, leading to significant deviations between monitoring results and the true physiological state.

[0004] Furthermore, this deficiency has become a technical bottleneck: complex scoliosis is easily misdiagnosed during screening, motor coordination cannot be accurately assessed during rehabilitation monitoring, and daily intervention recommendations lack specificity. Therefore, breaking through the limitations of single-dimensional monitoring and achieving comprehensive and accurate capture of the spine's three-dimensional posture is an urgent need to be addressed in this field. Summary of the Invention

[0005] Based on this, the purpose of this invention is to overcome the shortcomings of insufficient dimensions, complex algorithm process and unclear physical meaning in the existing technology of spinal posture monitoring, and to propose a spinal posture monitoring method and system. By calibrating a three-dimensional shape sensor, constructing a wavelength drift matrix, calculating a strain matrix, deriving the bending curvature and bending direction, and reconstructing the three-dimensional posture of the spine with a minimum rotation frame, the three-dimensional posture of the spine can be directly obtained.

[0006] The first aspect of the present invention proposes: A spinal posture monitoring method, wherein a wearable device is applied to the spine, the wearable device having a three-dimensional shape sensor internally, and the three-dimensional shape sensor having multiple fiber Bragg gratings arranged along its length direction internally, the method comprising: Calibration steps: When the three-dimensional shape sensor is in a calibrated state where it is straight and not subjected to external force, the calibration wavelength of each fiber Bragg grating is demodulated by a fiber grating demodulator and stored as an initial wavelength sequence according to their spatial distribution order inside the three-dimensional shape sensor. Detection steps: When a change in the shape of the three-dimensional shape sensor is detected, the corresponding deformation location is detected, and the current wavelength of each fiber Bragg grating inside the three-dimensional shape sensor at the deformation location is demodulated by the fiber Bragg demodulator. Steps for constructing the wavelength drift matrix: Based on the difference between the current wavelength of each fiber Bragg grating at the deformation location and the corresponding initial wavelength in the initial wavelength sequence, calculate the wavelength drift of each fiber Bragg grating, and construct the corresponding wavelength drift matrix according to its spatial distribution topology inside the three-dimensional shape sensor. Strain calculation steps: Based on the first preset algorithm, calculate the corresponding strain matrix according to the wavelength drift matrix; Curvature derivation steps: Based on the second preset algorithm, the bending curvature and bending direction generated by the three-dimensional shape sensor at the deformation location are derived according to the strain matrix; Three-dimensional reconstruction steps: Based on the minimum rotation frame of the three-dimensional curve, the tangent vector at the deformation point is calculated according to the curvature and the bending direction. The tangent vector is integrated along the length direction of the three-dimensional shape sensor and the three-dimensional spatial coordinates of the deformation point are obtained iteratively. The posture of the spine is determined according to the three-dimensional spatial coordinates.

[0007] The beneficial effects of this invention are as follows: This technical solution captures shape changes in real time and accurately locates deformation points using a three-dimensional shape sensor. First, a fiber optic grating demodulator is used to obtain the wavelength drift of each fiber Bragg grating and construct a wavelength drift matrix. Based on a first preset algorithm, the corresponding strain matrix is ​​calculated from the wavelength drift matrix. Then, based on a second preset algorithm, the core three-dimensional parameters, such as the bending curvature and bending direction of the three-dimensional shape sensor at the deformation point, are derived from the strain matrix. Relying on the spatial reconstruction capability of the minimum rotation frame of the three-dimensional curve, and combined with the above three-dimensional parameters, the target deformation shape of the three-dimensional shape sensor is restored from multiple dimensions, thereby completely mapping the actual posture of the spine. This effectively overcomes the limitations of single-dimensional monitoring in existing technologies and achieves comprehensive monitoring of the three-dimensional posture of the spine.

[0008] Furthermore, the step of constructing the wavelength drift matrix includes: During the calibration phase, the three-dimensional shape sensor is straightened and fixed, and the calibration wavelength of each fiber Bragg grating is acquired multiple times by the fiber grating demodulator and averaged to form the initial wavelength sequence. During the monitoring phase, the wavelength shift of each fiber Bragg grating is obtained based on the difference between the current wavelength collected by the three-dimensional shape sensor at the deformation location and the corresponding wavelength in the initial wavelength sequence. The wavelength shifts are then arranged and combined to form the wavelength shift matrix according to the arrangement order of the fiber Bragg gratings in the axial and cross-sectional areas of the three-dimensional shape sensor. Temperature compensation is applied to the wavelength drift to reduce the impact of ambient temperature changes on the strain calculation results.

[0009] Furthermore, the expression for the first preset algorithm is:

[0010] Where Δλ represents the wavelength shift of each fiber Bragg grating in the wavelength shift matrix, λ represents the center wavelength of the fiber Bragg grating, and P e Δε is the effective elastic-optical coefficient of the optical fiber material, and Δε is the longitudinal strain change of the optical fiber, which together constitute the strain matrix.

[0011] Furthermore, the expression for the second preset algorithm is:

[0012]

[0013] in, e i (i=1,2,3) represents the change in strain of the outer core of the optical fiber shape sensor. i i The angle between the optical fiber and the coordinate axes is represented by κ1(s), the first component of the bending curvature is represented by κ2(s), the second component of the bending curvature is represented by r, and r is the radius of curvature. i B The angle representing the bending direction, κ1 represents the first component of the bending direction, and κ2 represents the second component of the bending direction; The second preset algorithm obtains the bending curvature and bending direction at the cross section by substituting the strain change of each fiber measuring core at the same cross section into the expression.

[0014] Furthermore, the method also includes: Cubic spline interpolation is performed on the curvature and bending direction of the discretely distributed bending along the length direction of the three-dimensional shape sensor to generate a continuously varying sequence of curvature and bending direction along the axial direction of the three-dimensional shape sensor, thereby improving the spatial resolution of the sensing points and making the reconstructed three-dimensional spatial curve smoother.

[0015] Furthermore, the step of calculating the tangent vector at the deformation location based on the minimum rotational frame of the three-dimensional spatial curve according to the curvature and the bending direction includes: The vector field of the minimum rotation frame is initialized based on the preset three-dimensional anatomical coordinate system of the spine, and the origin and initial direction of the minimum rotation frame are calibrated by the relative installation posture of the three-dimensional shape sensor and the spine, so that the minimum rotation frame is aligned with the overall curvature direction of the spine. Using the bending curvature sequence and bending direction sequence after cubic spline interpolation as input, the bending curvature is decomposed into the two normal components of the minimum rotating frame, and the corresponding tangent vector change rate is solved. The tangent vector is integrated and iteratively solved along the length direction of the three-dimensional shape sensor to reconstruct the three-dimensional spatial coordinates at each discrete arc length in turn, forming the target deformation curve of the three-dimensional shape sensor, and the target deformation curve is mapped to the three-dimensional posture of the spine.

[0016] A second aspect of the present invention provides a spinal posture monitoring system applied to a wearable device mounted on the spine. The wearable device contains a three-dimensional shape sensor, and the three-dimensional shape sensor contains multiple fiber Bragg gratings arranged along its length. The system includes: The detection module is used to detect the corresponding deformation location when the shape of the three-dimensional shape sensor changes, and to demodulate the current wavelength of each fiber Bragg grating at the deformation location using a fiber Bragg demodulator. A storage module is used to store the initial wavelength sequence of each of the fiber Bragg gratings during the three-dimensional shape sensor calibration stage; The calculation module is used to calculate the wavelength shift of each fiber Bragg grating based on the initial wavelength sequence and the current wavelength, construct a wavelength shift matrix, and then convert the wavelength shift matrix into a strain matrix based on a first preset algorithm. The derivation module is used to derive the bending curvature and bending direction of the three-dimensional shape sensor at the deformation location based on the strain matrix using a second preset algorithm, and to perform cubic spline interpolation on the bending curvature and bending direction to generate a continuous bending curvature sequence and bending direction sequence. The reconstruction module is used to calculate the tangent vector at the deformation point based on the minimum rotation frame of the three-dimensional curve, according to the continuous bending curvature sequence and the bending direction sequence, reconstruct the three-dimensional spatial coordinate curve of the three-dimensional shape sensor through integral iteration, and determine the posture of the spine based on the three-dimensional spatial coordinate curve.

[0017] Furthermore, the calculation module is also used to perform temperature compensation on the calculated wavelength drift and to correct the abnormal drift based on the biomechanical constraints of spinal movement, so as to suppress the interference of ambient temperature changes and instantaneous jitter on the strain matrix.

[0018] Furthermore, the step of constructing the wavelength drift matrix includes: During the calibration phase, the three-dimensional shape sensor is straightened and fixed, and the calibration wavelength of each fiber Bragg grating is acquired multiple times by the fiber grating demodulator and averaged to form the initial wavelength sequence. During the monitoring phase, the wavelength shift of each fiber Bragg grating is obtained based on the difference between the current wavelength collected by the three-dimensional shape sensor at the deformation location and the corresponding wavelength in the initial wavelength sequence. The wavelength shifts are then arranged and combined to form the wavelength shift matrix according to the arrangement order of the fiber Bragg gratings in the axial and cross-sectional areas of the three-dimensional shape sensor. Temperature compensation is applied to the wavelength drift to reduce the impact of ambient temperature changes on the strain calculation results.

[0019] Furthermore, the expression for the first preset algorithm is:

[0020] Where Δλ represents the wavelength shift of each fiber Bragg grating in the wavelength shift matrix, λ represents the center wavelength of the fiber Bragg grating, and P e Δε is the effective elastic-optical coefficient of the optical fiber material, and Δε is the longitudinal strain change of the optical fiber, which together constitute the strain matrix.

[0021] Furthermore, the expression for the second preset algorithm is:

[0022]

[0023] in, e i (i=1,2,3) represents the change in strain of the outer core of the optical fiber shape sensor. i i The angle between the optical fiber and the coordinate axes is represented by κ1(s), the first component of the bending curvature is represented by κ2(s), the second component of the bending curvature is represented by r, and r is the radius of curvature. i B The angle representing the bending direction, κ1 represents the first component of the bending direction, and κ2 represents the second component of the bending direction; The second preset algorithm obtains the bending curvature and bending direction at the cross section by substituting the strain change of each fiber measuring core at the same cross section into the expression.

[0024] Furthermore, the method also includes: Cubic spline interpolation is performed on the curvature and bending direction of the discretely distributed bending along the length direction of the three-dimensional shape sensor to generate a continuously varying sequence of curvature and bending direction along the axial direction of the three-dimensional shape sensor, thereby improving the spatial resolution of the sensing points and making the reconstructed three-dimensional spatial curve smoother.

[0025] Furthermore, the step of calculating the tangent vector at the deformation location based on the minimum rotational frame of the three-dimensional spatial curve according to the curvature and the bending direction includes: The vector field of the minimum rotation frame is initialized based on the preset three-dimensional anatomical coordinate system of the spine, and the origin and initial direction of the minimum rotation frame are calibrated by the relative installation posture of the three-dimensional shape sensor and the spine, so that the minimum rotation frame is aligned with the overall curvature direction of the spine. Using the bending curvature sequence and bending direction sequence after cubic spline interpolation as input, the bending curvature is decomposed into the two normal components of the minimum rotating frame, and the corresponding tangent vector change rate is solved. The tangent vector is integrated and iteratively solved along the length direction of the three-dimensional shape sensor to reconstruct the three-dimensional spatial coordinates at each discrete arc length in turn, forming the target deformation curve of the three-dimensional shape sensor, and the target deformation curve is mapped to the three-dimensional posture of the spine.

[0026] A third aspect of the present invention provides a computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the spinal posture monitoring method described above.

[0027] A fourth aspect of the present invention provides a readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the spinal posture monitoring method as described above.

[0028] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0029] Figure 1 A flowchart of the spinal posture monitoring method provided in the first embodiment of the present invention; Figure 2 This is a structural block diagram of the spinal posture monitoring system provided in the second embodiment of the present invention.

[0030] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0031] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0032] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] Please see Figure 1 This embodiment provides a spinal posture monitoring method applied to a wearable device mounted on the spine. The wearable device contains a three-dimensional shape sensor, and multiple fiber Bragg gratings are arranged along its length inside the three-dimensional shape sensor. The method includes the following steps: Step S10: Calibrate the initial wavelength sequence Before factory use or first use, the three-dimensional shape sensor is straightened and fixed so that it is in a state without external force and without bending. The calibration wavelength of each fiber Bragg grating is demodulated multiple times by a fiber Bragg demodulator. The sampling results are averaged to construct the initial wavelength sequence of the three-dimensional shape sensor in the straightened state. The initial wavelength sequence is stored in the memory of the wearable device as a reference for subsequent calculations. It's important to note that, firstly, when the wearable device is worn close to the spine, changes in spinal posture cause synchronous deformation of the 3D shape sensor. The system first detects the specific location of the deformation (e.g., the 3rd-4th thoracic vertebrae, the 2nd lumbar vertebrae), providing a spatial reference for subsequent precise localization of abnormal spinal posture areas. Based on a pre-defined algorithm, the strain change at the deformation location is calculated using the fiber Bragg grating (FBG) built into the sensor. Specifically, the FBG is the core sensing element; its grating period changes with deformation, causing a change in the wavelength of reflected light. The amount of strain change directly reflects the degree of sensor deformation and is crucial intermediate data for associating spinal posture.

[0035] Step S20: Acquire the current wavelength and construct the wavelength drift matrix. When a user wears the wearable device and begins to move, changes in spinal posture cause synchronous deformation of the three-dimensional shape sensor. The system periodically acquires the wavelength values ​​of all fiber Bragg gratings at the current moment through a fiber Bragg demodulator, subtracts them from the wavelengths at the corresponding positions in the initial wavelength sequence, and obtains the wavelength shift of each fiber Bragg grating.

[0036] Step S30: Calculate the strain matrix based on the first preset algorithm. By substituting the wavelength drift values ​​from the wavelength drift matrix into the physical relationships corresponding to the first preset algorithm, and calculating the longitudinal strain change of each fiber measurement core based on the effective elastic-optical coefficient of the fiber material and the center wavelength of the grating, a strain matrix is ​​obtained. This strain matrix is ​​arranged according to the axial position of the three-dimensional shape sensor and the position of each measurement core within the fiber cross-section, reflecting the tensile or compressive state of the three-dimensional shape sensor at each measurement point.

[0037] Step S40: Derive the bending curvature and bending direction based on the second preset algorithm. Based on the annular arrangement of multiple measuring cores within the fiber cross-section of the 3D shape sensor, the strain changes corresponding to each measuring core at the same cross-section are combined to form a strain vector. This vector is then substituted into the expression in the second preset algorithm to solve for the bending curvature and bending direction at that cross-section. The above solution process is repeated along the length of the 3D shape sensor to obtain discrete bending curvature and bending direction sequences.

[0038] In this embodiment, the bending curvature and bending direction are directly calculated by the physical model of the second preset algorithm, and the calculation process is simple and the physical meaning is clear.

[0039] Step S50: Perform cubic spline interpolation on the bending curvature and bending direction. Because fiber Bragg gratings are discretely distributed along the axial direction, directly using discrete curvature and bending direction for 3D reconstruction can lead to broken lines or local unevenness in the reconstructed curve in some intervals. To improve spatial resolution and obtain a smoother 3D reconstruction curve, this embodiment employs a cubic spline interpolation algorithm to interpolate the curvature and bending direction sequences along the length of the 3D shape sensor, making them continuously change on the arc-length coordinate system. This results in new, equally spaced curvature and bending direction at the interpolation points.

[0040] It should be noted that cubic spline interpolation targets the curvature and direction of bending, not the initial wavelength sequence, and is not used to generate the wavelength drift matrix.

[0041] Step S60: Reconstruct the 3D pose based on the minimum rotation frame. After interpolation, the obtained continuous curvature and bending direction are used as input to construct a minimum rotation frame for the three-dimensional curve. Initial tangent and normal vectors are set in a preset spinal anatomical coordinate system, and the minimum rotation frame is calibrated based on the installation posture of the three-dimensional shape sensor and the spine. The rate of change of the tangent vector is calculated based on the projection of the curvature onto the two orthogonal normal components. The tangent vector is integrated along the arc length direction, and the three-dimensional spatial coordinates of each interpolation point are iteratively solved to reconstruct the target deformation curve of the three-dimensional shape sensor.

[0042] Since this embodiment relies solely on bending curvature and bending direction for three-dimensional reconstruction, the calculation process is relatively simple and stable. Finally, based on the relationship between the three-dimensional shape sensor and the spine's fitted installation, the target deformation curve is mapped to the spine's three-dimensional posture, enabling real-time monitoring of the spine's posture.

[0043] Please see Figure 2 The second embodiment of the present invention provides: A spinal posture monitoring system is applied to a wearable device mounted on the spine. The wearable device contains a three-dimensional shape sensor, and the three-dimensional shape sensor has multiple fiber Bragg gratings arranged along its length. The system includes: The detection module is used to detect the corresponding deformation location when the shape of the three-dimensional shape sensor changes, and to demodulate the current wavelength of each fiber Bragg grating at the deformation location using a fiber Bragg demodulator. A storage module is used to store the initial wavelength sequence of each of the fiber Bragg gratings during the three-dimensional shape sensor calibration stage; The calculation module is used to calculate the wavelength shift of each fiber Bragg grating based on the initial wavelength sequence and the current wavelength, construct a wavelength shift matrix, and then convert the wavelength shift matrix into a strain matrix based on a first preset algorithm. The derivation module is used to derive the bending curvature and bending direction of the three-dimensional shape sensor at the deformation location based on the strain matrix using a second preset algorithm, and to perform cubic spline interpolation on the bending curvature and bending direction to generate a continuous bending curvature sequence and bending direction sequence. The reconstruction module is used to calculate the tangent vector at the deformation point based on the minimum rotation frame of the three-dimensional curve, according to the continuous bending curvature sequence and the bending direction sequence, reconstruct the three-dimensional spatial coordinate curve of the three-dimensional shape sensor through integral iteration, and determine the posture of the spine based on the three-dimensional spatial coordinate curve.

[0044] Furthermore, the calculation module is also used to perform temperature compensation on the calculated wavelength drift and to correct the abnormal drift based on the biomechanical constraints of spinal movement, so as to suppress the interference of ambient temperature changes and instantaneous jitter on the strain matrix.

[0045] Furthermore, the step of constructing the wavelength drift matrix includes: During the calibration phase, the three-dimensional shape sensor is straightened and fixed, and the calibration wavelength of each fiber Bragg grating is acquired multiple times by the fiber grating demodulator and averaged to form the initial wavelength sequence. During the monitoring phase, the wavelength shift of each fiber Bragg grating is obtained based on the difference between the current wavelength collected by the three-dimensional shape sensor at the deformation location and the corresponding wavelength in the initial wavelength sequence. The wavelength shifts are then arranged and combined to form the wavelength shift matrix according to the arrangement order of the fiber Bragg gratings in the axial and cross-sectional areas of the three-dimensional shape sensor. Temperature compensation is applied to the wavelength drift to reduce the impact of ambient temperature changes on the strain calculation results.

[0046] Furthermore, the expression for the first preset algorithm is:

[0047] Where Δλ represents the wavelength shift of each fiber Bragg grating in the wavelength shift matrix, λ represents the center wavelength of the fiber Bragg grating, and P e Δε is the effective elastic-optical coefficient of the optical fiber material, and Δε is the longitudinal strain change of the optical fiber, which together constitute the strain matrix.

[0048] Furthermore, the expression for the second preset algorithm is:

[0049]

[0050] in, e i (i=1,2,3) represents the change in strain of the outer core of the optical fiber shape sensor. i i The angle between the optical fiber and the coordinate axes is represented by κ1(s), the first component of the bending curvature is represented by κ2(s), the second component of the bending curvature is represented by r, and r is the radius of curvature. i B The angle representing the bending direction, κ1 represents the first component of the bending direction, and κ2 represents the second component of the bending direction; The second preset algorithm obtains the bending curvature and bending direction at the cross section by substituting the strain change of each fiber measuring core at the same cross section into the expression.

[0051] Furthermore, the method also includes: Cubic spline interpolation is performed on the curvature and bending direction of the discretely distributed bending along the length direction of the three-dimensional shape sensor to generate a continuously varying sequence of curvature and bending direction along the axial direction of the three-dimensional shape sensor, thereby improving the spatial resolution of the sensing points and making the reconstructed three-dimensional spatial curve smoother.

[0052] Furthermore, the step of calculating the tangent vector at the deformation location based on the minimum rotational frame of the three-dimensional spatial curve according to the curvature and the bending direction includes: The vector field of the minimum rotation frame is initialized based on the preset three-dimensional anatomical coordinate system of the spine, and the origin and initial direction of the minimum rotation frame are calibrated by the relative installation posture of the three-dimensional shape sensor and the spine, so that the minimum rotation frame is aligned with the overall curvature direction of the spine. Using the bending curvature sequence and bending direction sequence after cubic spline interpolation as input, the bending curvature is decomposed into the two normal components of the minimum rotating frame, and the corresponding tangent vector change rate is solved. The tangent vector is integrated and iteratively solved along the length direction of the three-dimensional shape sensor to reconstruct the three-dimensional spatial coordinates at each discrete arc length in turn, forming the target deformation curve of the three-dimensional shape sensor, and the target deformation curve is mapped to the three-dimensional posture of the spine.

[0053] The third embodiment of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the spinal posture monitoring method described above.

[0054] The fourth embodiment of the present invention proposes a readable storage medium on which a computer program is stored, which, when executed by a processor, implements the spinal posture monitoring method as described above.

[0055] In summary, the spinal posture monitoring method and system provided in the above embodiments of the present invention can detect the posture of the spine in all aspects, thereby improving the monitoring efficiency of the spine.

[0056] It should be noted that the above modules can be functional modules or program modules, and can be implemented through software or hardware. For modules implemented through hardware, the above modules can reside in the same processor; or the above modules can be located in different processors in any combination.

[0057] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0058] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0059] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0060] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0061] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for monitoring spinal posture, characterized in that, A wearable device applied to the spine, the wearable device having a three-dimensional shape sensor internally, the three-dimensional shape sensor having multiple fiber Bragg gratings arranged along its length direction inside, the method comprising: Calibration steps: When the three-dimensional shape sensor is in a calibrated state where it is straight and not subjected to external force, the calibration wavelength of each fiber Bragg grating is demodulated by a fiber grating demodulator and stored as an initial wavelength sequence according to their spatial distribution order inside the three-dimensional shape sensor. Detection steps: When a change in the shape of the three-dimensional shape sensor is detected, the corresponding deformation location is detected, and the current wavelength of each fiber Bragg grating inside the three-dimensional shape sensor at the deformation location is demodulated by the fiber Bragg demodulator. Steps for constructing the wavelength drift matrix: Based on the difference between the current wavelength of each fiber Bragg grating at the deformation location and the corresponding initial wavelength in the initial wavelength sequence, calculate the wavelength drift of each fiber Bragg grating, and construct the corresponding wavelength drift matrix according to its spatial distribution topology inside the three-dimensional shape sensor. Strain calculation steps: Based on the first preset algorithm, calculate the corresponding strain matrix according to the wavelength drift matrix; Curvature derivation steps: Based on the second preset algorithm, the bending curvature and bending direction generated by the three-dimensional shape sensor at the deformation location are derived according to the strain matrix; Three-dimensional reconstruction steps: Based on the minimum rotation frame of the three-dimensional curve, the tangent vector at the deformation point is calculated according to the curvature and the bending direction. The tangent vector is integrated along the length direction of the three-dimensional shape sensor and the three-dimensional spatial coordinates of the deformation point are obtained iteratively. The posture of the spine is determined according to the three-dimensional spatial coordinates.

2. The spinal posture monitoring method according to claim 1, characterized in that, The steps for constructing the wavelength drift matrix include: During the calibration phase, the three-dimensional shape sensor is straightened and fixed, and the calibration wavelength of each fiber Bragg grating is acquired multiple times by the fiber grating demodulator and averaged to form the initial wavelength sequence. During the monitoring phase, the wavelength shift of each fiber Bragg grating is obtained based on the difference between the current wavelength collected by the three-dimensional shape sensor at the deformation location and the corresponding wavelength in the initial wavelength sequence. The wavelength shifts are then arranged and combined to form the wavelength shift matrix according to the arrangement order of the fiber Bragg gratings in the axial and cross-sectional areas of the three-dimensional shape sensor. Temperature compensation is applied to the wavelength drift to reduce the impact of ambient temperature changes on the strain calculation results.

3. The spinal posture monitoring method according to claim 1 or 2, characterized in that, The expression for the first preset algorithm is: Where Δλ represents the wavelength shift of each fiber Bragg grating in the wavelength shift matrix, λ represents the center wavelength of the fiber Bragg grating, and P e Δε is the effective elastic-optical coefficient of the optical fiber material, and Δε is the longitudinal strain change of the optical fiber, which together constitute the strain matrix.

4. The spinal posture monitoring method according to any one of claims 1 to 2, characterized in that, The expression for the second preset algorithm is: in, ε i (i=1,2,3) represents the change in strain of the outer core of the optical fiber shape sensor. θ i The angle between the optical fiber and the coordinate axes is represented by κ1(s), the first component of the bending curvature is represented by κ2(s), the second component of the bending curvature is represented by r, and r is the radius of curvature. θ B The angle representing the bending direction, κ1 represents the first component of the bending direction, and κ2 represents the second component of the bending direction; The second preset algorithm obtains the bending curvature and bending direction at the cross section by substituting the strain change of each fiber measuring core at the same cross section into the expression.

5. The spinal posture monitoring method according to any one of claims 1 to 2, characterized in that, The method further includes: Cubic spline interpolation is performed on the curvature and bending direction of the discretely distributed bending along the length direction of the three-dimensional shape sensor to generate a continuously varying sequence of curvature and bending direction along the axial direction of the three-dimensional shape sensor, thereby improving the spatial resolution of the sensing points and making the reconstructed three-dimensional spatial curve smoother.

6. The spinal posture monitoring method according to any one of claims 1 to 2, characterized in that, The step of calculating the tangent vector at the deformation location based on the minimum rotation frame of the three-dimensional spatial curve according to the curvature and the bending direction includes: The vector field of the minimum rotation frame is initialized based on the preset three-dimensional anatomical coordinate system of the spine, and the origin and initial direction of the minimum rotation frame are calibrated by the relative installation posture of the three-dimensional shape sensor and the spine, so that the minimum rotation frame is aligned with the overall curvature direction of the spine. Using the bending curvature sequence and bending direction sequence after cubic spline interpolation as input, the bending curvature is decomposed into the two normal components of the minimum rotating frame, and the corresponding tangent vector change rate is solved. The tangent vector is integrated and iteratively solved along the length direction of the three-dimensional shape sensor to reconstruct the three-dimensional spatial coordinates at each discrete arc length in turn, forming the target deformation curve of the three-dimensional shape sensor, and the target deformation curve is mapped to the three-dimensional posture of the spine.

7. A spinal posture monitoring system, characterized in that, A wearable device for placement on the spine, the wearable device having a three-dimensional shape sensor internally, the three-dimensional shape sensor having multiple fiber Bragg gratings arranged along its length, the system comprising: The detection module is used to detect the corresponding deformation location when the shape of the three-dimensional shape sensor changes, and to demodulate the current wavelength of each fiber Bragg grating at the deformation location using a fiber Bragg demodulator. A storage module is used to store the initial wavelength sequence of each of the fiber Bragg gratings during the three-dimensional shape sensor calibration stage; The calculation module is used to calculate the wavelength shift of each fiber Bragg grating based on the initial wavelength sequence and the current wavelength, construct a wavelength shift matrix, and then convert the wavelength shift matrix into a strain matrix based on a first preset algorithm. The derivation module is used to derive the bending curvature and bending direction of the three-dimensional shape sensor at the deformation location based on the strain matrix using a second preset algorithm, and to perform cubic spline interpolation on the bending curvature and bending direction to generate a continuous bending curvature sequence and bending direction sequence. The reconstruction module is used to calculate the tangent vector at the deformation point based on the minimum rotation frame of the three-dimensional curve, according to the continuous bending curvature sequence and the bending direction sequence, reconstruct the three-dimensional spatial coordinate curve of the three-dimensional shape sensor through integral iteration, and determine the posture of the spine based on the three-dimensional spatial coordinate curve.

8. The spinal posture monitoring system according to claim 7, characterized in that, The calculation module is also used to perform temperature compensation on the calculated wavelength drift and to correct the abnormal drift based on the biomechanical constraints of spinal movement, so as to suppress the interference of ambient temperature changes and instantaneous jitter on the strain matrix.

9. A computer device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the spinal posture monitoring method as described in any one of claims 1 to 6.

10. A readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the spinal posture monitoring method as described in any one of claims 1 to 6.

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