Puncture force and shape sensing puncture needle and method based on fiber bragg grating sensing

Abstract

The invention provides a puncture force and shape sensing puncture needle and method based on fiber bragg grating sensing. The puncture needle and method are used for pulmonary nodule puncture biopsy under a bronchoscope. The puncture needle provided by the invention comprises a needle body assembly and a sensing assembly, the needle body assembly is connected with the sensing assembly to form a puncture needle body with a sensing function; the structure is ingenious, the annular groove structure is arranged on the puncture needle and used for collecting tissue cell samples, the FBG optical fiber is integrated on the puncture needle through the structural design, the shape sensing function and the puncture force sensing function of the puncture needle are achieved, more puncture information is provided for an operation doctor, and the puncture precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical equipment, in particular to a puncture force and shape sensing puncture needle and method based on fiber Bragg grating sensing. BACKGROUND

[0002] Puncture biopsy is an effective means for clinical diagnosis of pulmonary nodules, but the accuracy is difficult to guarantee. The FBG fiber has a small size and good flexibility. The puncture needle designed in the present application can meet the requirements of puncture sampling, has shape sensing capability and sensing puncture force information, and provides more puncture information for doctors, thereby improving the puncture accuracy.

[0003] The puncture biopsy of transbronchial pulmonary nodules is generally performed by positioning the bronchoscope to the target position by a doctor, and then placing the puncture needle into the working channel of the bronchoscope to achieve puncture. Due to the complex bronchial pathway, the interaction between the puncture needle and the bronchoscope during the puncture needle entering process causes the puncture needle to deviate from the initial target point, and it is difficult to accurately position the puncture point. The actual puncture process also depends on the doctor's sense to judge whether the puncture is successful, which puts high requirements on the doctor's quality.

[0004] The FBG fiber has a small diameter and a controllable length, and has a certain flexibility. The puncture needle designed in the present application has a clever structure design, and four optical fibers are used to realize the shape sensing of the puncture needle and the function of detecting the axial force of the puncture needle. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a puncture force and shape sensing puncture needle and method based on fiber Bragg grating sensing.

[0006] According to the puncture force and shape sensing puncture needle based on fiber Bragg grating sensing provided by the present application, the puncture force and shape sensing puncture needle comprises a needle body assembly and a sensing assembly.

[0007] The needle body assembly is composed of a needle tip, an elastic element, a slotted needle body segment, a needle tail segment and a hollow guide wire which are coaxially connected in sequence; the elastic element is bonded at both ends to the needle tip and the slotted needle body segment; and the hollow guide wire is fused to the needle tail segment.

[0008] The sensing assembly comprises three circumferentially distributed first optical fiber sensors and an axially arranged second optical fiber sensor.

[0009] Preferably, the rear part of the needle tip is provided with a needle tip hole, a needle tip column and a needle tip slot; the elastic element has a hollow structure and is bonded at both ends to the needle tip and the slotted needle body segment; and the needle tip hole is used to fix the front end of the second optical fiber sensor.

[0010] Preferably, the slotted needle segment is provided with a side slot, a front slot and a column hole; the side slot is used for tissue sample collection; the column hole is connected with the needle tip column.

[0011] Preferably, the needle tail segment is provided with three circumferentially distributed sensor mounting grooves and a center through hole; the hollow guide wire is fused with the needle tail segment.

[0012] Preferably, the first optical fiber sensor is embedded in the needle tail segment mounting groove; the first optical fiber sensor is provided with a plurality of FBG sensors distributed at equal intervals.

[0013] Preferably, the front end of the second optical fiber sensor is fixed to the needle tip hole; the second optical fiber sensor is provided with two FBG sensors; the second optical fiber sensor extends through the center through hole of the needle body to the hollow guide wire; the second optical fiber sensor extends to the inside of the hollow guide wire through the center through hole of the elastic element, the slotted needle segment and the needle tail segment in turn; the two FBG sensors are respectively located in the front segment of the optical fiber sensor and the rear segment of the optical fiber sensor 4.

[0014] Preferably, the hollow guide wire is provided with an optical fiber support, the optical fiber support is provided with a support hole and three circumferentially distributed optical fiber positioning grooves; the three optical fiber positioning grooves respectively fix the tail ends of the three first optical fiber sensors.

[0015] The application also provides a puncture axial force and shape sensing method of fiber Bragg grating sensing, which applies the puncture force and shape sensing puncture needle of fiber Bragg grating sensing in the above.

[0016]

[0017] Wherein, λ B is the center wavelength of the reflected signal, Δλ B is the wavelength shift, P e is the strain optical coefficient, ε is the fiber strain, α A is the thermal expansion coefficient, α n is the thermo-optic coefficient, ΔT is the temperature change, k ε is the strain sensitivity coefficient, k T is the temperature sensitivity coefficient, k T ΔT is the temperature compensation term, k ε ε is the strain compensation term.

[0018] The puncture needle is subjected to axial force F z and transverse force F l when puncturing, wherein the transverse force part has no effect on the optical fiber sensor, and only the axial force F z has an effect on the second optical fiber sensor;

[0019] When the puncture needle is subjected to axial force F z , the axial force F z is decomposed into two parts:

[0020] F z =k1Δz+k2Δz=k1Δz+k2Lε

[0021] Wherein k1Δz corresponds to the deformation resistance of the elastic element, k2Lε is the resistance generated by the strain of the second optical fiber sensor, Δz is the axial deformation displacement of the elastic element, L is the grating length, and ε is the fiber strain;

[0022] Through the deformation compatibility condition, we have:

[0023]

[0024] And deduce:

[0025]

[0026] A direct correlation between the fiber strain ε and F z is established;

[0027] Substitute ε into the FBG formula to finally establish the quantitative relationship between F z and the wavelength shift Δλ B :

[0028]

[0029] When the ambient temperature changes little, the k T ΔT term is discarded, and the model directly calculates the axial force from the wavelength change through the calibration coefficients k1, k2, and k ε ;

[0030] When the needle tip is subjected to both lateral force F l and axial force F z , the elastic element compensates for the lateral displacement through micro-deformation and limits the lateral movement through the joint surface, and the strain ε generated in the interior is transmitted to the FBG grating area of the optical fiber sensor; the wavelength shift Δλ B of the FBG is monitored in real time by the modulator, and the mapping relationship between F z and Δλ B is established through the pre-established mathematical model, and finally the value of the axial puncture force F z is calculated.

[0031] Preferably, when the puncture needle deforms, the FBG sensor of the first optical fiber sensor generates strain, and a three-dimensional shape is reconstructed through a distributed sensing algorithm.

[0032] Preferably, the side grooves of the slotted needle segment collect tissue samples during the puncture.

[0033] Compared with the prior art, the present application has the following beneficial effects:

[0034] 1、The present application collects tissue cell samples by setting a plurality of ring grooves on the puncture needle, thereby improving the puncture needle collection efficiency and avoiding damage to the puncture object caused by multiple puncture collections;

[0035] 2、The present application uses four optical fiber sensors to enable the puncture needle to have shape sensing and puncture force sensing functions;

[0036] 3、The present application has different performances when the puncture needle is subjected to axial force and lateral force through ingenious structural design, thereby providing a basis for realizing puncture force sensing of the puncture needle;

[0037] 4、The grating array distribution of the optical fiber sensor used in the present application can realize the sensing of the axial force and shape of the puncture needle under the structure of the present application, thereby providing a method for integrating the optical fiber sensor and the puncture needle. BRIEF DESCRIPTION OF DRAWINGS

[0038] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the following drawings:

[0039] Figure 1 Fig. 1 is a schematic diagram of the overall structure of a puncture force and shape sensing puncture needle;

[0040] Figure 2 Fig. 2 is a schematic diagram of the structure of a needle tip;

[0041] Figure 3 Fig. 3 is a sectional view of the needle tip;

[0042] Figure 4 Fig. 4 is an assembly diagram of the needle tip and the optical fiber sensor;

[0043] Figure 5 Fig. 5 is a schematic diagram of the structure of an elastic element;

[0044] Figure 6 Fig. 6 is a schematic diagram of the structure of a slotted needle segment

[0045] Figure 7 Fig. 7 is a sectional view of the slotted needle segment;

[0046] Figure 8 Fig. 8 is a schematic diagram of the structure of a needle tail segment

[0047] Figure 9 Fig. 9 is a sectional view of the needle tail segment;

[0048] Figure 10 Fig. 10 is a schematic diagram of the structure of an optical fiber support;

[0049] Figure 11 schematic diagram of FBG sensor distribution for the first optical fiber sensor;

[0050] Figure 12 schematic diagram of FBG sensor distribution for the second optical fiber sensor;

[0051] Figure 13 working principle diagram of the puncture force and shape sensing puncture needle.

[0052] wherein:

[0053] needle tip 1 needle tip hole 103

[0054] elastic element 2 side groove 301

[0055] grooved needle body segment 3 front groove 302

[0056] needle tail segment 4 column hole 303

[0057] first optical fiber sensor 5 sensor mounting groove 401

[0058] hollow guide wire 6 center through hole 402

[0059] optical fiber support 7 first FBG sensor 501

[0060] second optical fiber sensor 8 support hole 701

[0061] needle tip groove 101 optical fiber positioning groove 702

[0062] needle tip column 102 second FBG sensor 801 DETAILED DESCRIPTION

[0063] The present application will be described in detail below with specific embodiments. The following examples will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of changes and improvements can be made. These are within the scope of the present application.

[0064] Example 1:

[0065] Reference Figure 1The application provides a puncture force and shape sensing puncture needle based on fiber Bragg grating sensing, which comprises a needle body assembly and a sensing assembly.

[0066] The rear part of the needle tip 1 is provided with a needle tip hole 103, a needle tip column body 102 and a needle tip groove 101; the elastic element 2 is a hollow structure, and the two ends thereof are bonded with the needle tip 1 and the slotted needle body segment 3 respectively; the needle tip hole 103 is used for fixing the front end of the second fiber sensor 7. The slotted needle body segment 3 is provided with a side groove 301, a front groove 302 and a column hole 303; the side groove 301 is used for tissue sample collection; and the column hole 303 is connected with the needle tip column body 102 in cooperation. The rear segment 4 of the needle is provided with three sensor mounting grooves 401 which are uniformly distributed in the circumferential direction and a central through hole 402; and the hollow guide wire 6 is fused with the rear segment 4 of the needle. The first fiber sensor 5 is embedded in the needle tail mounting groove 401; the first fiber sensor 5 is provided with a plurality of first FBG sensors 501 which are distributed at equal intervals. The front end of the second fiber sensor 8 is fixed in the needle tip hole 103; the second fiber sensor 8 is provided with two second FBG sensors 801; the second fiber sensor 8 extends to the hollow guide wire 6 through the central through hole of the needle body; the second fiber sensor 8 extends to the inside of the hollow guide wire 6 through the central through hole 402 of the elastic element 2, the slotted needle body segment 3 and the rear segment 4 of the needle in sequence; and the two second FBG sensors 801 are respectively located at the front segment of the fiber sensor and the rear segment of the fiber sensor 4. The hollow guide wire 6 is provided with a fiber support 7; the fiber support 7 is provided with a support hole 701 and three fiber positioning grooves 702 which are uniformly distributed in the circumferential direction; and the three fiber positioning grooves 702 respectively fix the tail ends of the three first fiber sensors 5.

[0067] The application further provides a puncture force and shape sensing method based on fiber Bragg grating sensing. z When the needle tip is subjected to an axial force F

[0068]

[0069] Wherein, λ B is the center wavelength of the reflected signal, Δλ B is the wavelength shift, P e is the strain optical coefficient, ε is the fiber strain, α A is the thermal expansion coefficient, α n is the thermo-optic coefficient, and ΔT is the change amount of temperature.ε k is the strain sensitivity coefficient T k is the temperature sensitivity coefficient T ΔT is the temperature compensation term ε ε is the strain compensation term

[0070] The puncture needle is subjected to an axial force F z and a lateral force F l , wherein the lateral force component has no effect on the optical fiber sensor 4, only the axial force F z has an effect on the optical fiber sensor 4;

[0071] When the puncture needle is subjected to an axial force F z , the axial force F z is decomposed into two components:

[0072] F z = k1Δz + k2Lε

[0073] wherein k1Δz corresponds to the deformation resistance of the elastic element 2, k2Lε is the resistance generated by the strain of the second optical fiber sensor 8, Δz is the axial deformation displacement of the elastic element 2, L is the grating length, and ε is the fiber strain;

[0074] By the deformation compatibility condition, we obtain:

[0075]

[0076] And we derive:

[0077]

[0078] A direct correlation between the fiber strain ε and F z is established;

[0079] Substituting ε into the FBG formula, we finally establish a quantitative relationship between F z and the wavelength shift Δλ B :

[0080]

[0081] When the ambient temperature changes little, the k T ΔT term is discarded, and then the model directly calculates the axial force from the wavelength change through the calibration coefficients k1, k2, and k ε ;

[0082] When the needle tip is subjected to a lateral force F l and an axial force F zWhen the elastic element compensates for the lateral displacement by micro-deformation and the joint surface limits the lateral movement, the strain ε generated in the elastic element is transmitted to the FBG grating area of the optical fiber sensor 4; the wavelength shift Δλ of the FBG is monitored in real time by the modulator B , and the mapping relationship between the calibrated F z and Δλ B is established by a pre-established mathematical model, so that the value of the axial puncture force F z is finally calculated.

[0083] When the puncture needle deforms, the first FBG sensor 501 of the first optical fiber sensor 5 generates strain, and the three-dimensional shape is reconstructed through a distributed sensing algorithm. The side groove 301 of the grooved needle body segment 3 collects tissue samples during the puncture process.

[0084] Embodiment 2:

[0085] As shown in Figures 1 to 13 , the embodiment of the present application provides a puncture force and shape sensing puncture needle based on fiber Bragg grating sensing. The FBG optical fiber is integrated on the puncture needle through structural design, and a ring groove structure is arranged on the puncture needle for collecting tissue cell samples, so that the shape sensing and puncture force sensing functions of the puncture needle are realized, and the puncture needle is used for lung nodule puncture biopsy under a bronchoscope.

[0086] As shown in Figure 1 and Figure 4 , the present application provides a puncture force and shape sensing puncture needle based on fiber Bragg grating sensing, which comprises a needle body assembly and a sensing assembly; the needle body assembly comprises a needle tip 1, an elastic element 2, a grooved needle body segment 3, a needle tail end 4 and a hollow guide wire 6, and the needle body assembly is connected in sequence along the axial direction from the distal end (needle tip) to the proximal end (needle tail); the sensing assembly comprises a first optical fiber sensor 5, an optical fiber support 7 and a second optical fiber sensor 8; the front end of the second optical fiber sensor 8 is connected to the needle tip 1 and extends axially along the needle tip 1, and enters the hollow guide wire 6 through the hole of the needle tail segment 4; the needle tip 1, the elastic element 2, the grooved needle body segment 3, the needle tail segment 4 and the hollow guide wire 6 are coaxially arranged; the left end of the hollow guide wire 6 is fusion spliced with the needle tail segment 4.

[0087] As shown in Figures 2 to 7 , the elastic element 2 is connected with the needle tip 1 and the grooved needle body segment 3 by adhesive bonding, and is attached to the needle tip groove 101 and the grooved needle body segment side groove 301; the second optical fiber sensor 8 is fixed on the needle tip 1 through the needle tip hole 103 arranged at the rear of the needle tip, so as to meet the purpose of axial force detection; a plurality of grooved needle body segment side grooves 301 are arranged on the outer side of the grooved needle body segment 3, so that the puncture needle can collect tissue cell samples; the grooved needle body segment 3 is provided with a grooved needle body segment column hole 303 in the center, which cooperates with the needle tip column body 102 to realize the connection of the needle tip 1 and the grooved needle body segment 3.

[0088] AsFigures 8 to 10 As shown in the figure, the first fiber sensor 5 is bonded in the needle tail section groove 401 by distributing three needle tail section grooves 401 on the needle tail section 4 along the circumferential direction, so as to ensure the symmetrical distribution of the three fiber sensors and to calculate the three-dimensional bending curvature by strain difference; the needle tail section groove 401 is arranged at the center of the needle tail section 4 for the second fiber sensor 8 to pass through; the fiber support 7 is arranged with a fiber support hole 701 so as to be placed on the hollow guide wire 6; the first fiber sensor 5 is supported by distributing three fiber support grooves 702 along the circumferential direction of the fiber support 7.

[0089] As shown in the figure, Figure 11 the first fiber sensor 5 is arranged with a plurality of first fiber sensor first FBG sensors 501, and the plurality of first fiber sensor first FBG sensors 501 are distributed at equal intervals along the fiber. The strain data of different positions of the needle body are synchronously collected by the plurality of FBG points, and the three-dimensional shape of the puncture needle in the complex bronchial path is reconstructed by using the distributed sensing principle.

[0090] As shown in the figure, Figure 12 the second fiber sensor 8 is arranged with two second fiber sensor second FBG sensors 801, wherein the first FBG sensor is located at the front end of the fiber sensor, and the second FBG sensor is located at the rear end of the fiber sensor 4. The axial force borne by the needle tip is detected by using the wavelength shift difference of the two FBGs, the front FBG directly senses the force borne by the needle tip, and the rear FBG serves as a reference point. The size and direction of the force are calculated by comparing the strain changes of the two.

[0091] In the embodiment, the relationship between the wavelength displacement of the fiber Bragg grating and the strain can be described as:

[0092]

[0093] Wherein, λ B is the center wavelength of the reflected signal, Δλ B is the wavelength shift, P e is the strain optical coefficient, ε is the fiber strain, α A is the thermal expansion coefficient, α n is the thermo-optic coefficient, ΔT is the change amount of temperature, k ε is the strain sensitivity coefficient, k T is the temperature sensitivity coefficient, k T ΔT is the temperature compensation term, k ε ε is the strain compensation term.

[0094] The puncture needle bears an axial force F z and a transverse force F lThe lateral force component does not affect the fiber optic sensor 4 due to the constraint of the joint surface and the micro-deformation compensation of the elastic element; only the axial force F is applied. z It has an impact on the fiber optic sensor 4.

[0095] When the puncture needle is subjected to an axial force F z At that time, axial force F z It is broken down into two parts:

[0096] F z =k1Δz+k2Δz=k1Δz+k2Lε

[0097] Where k1Δz corresponds to the deformation resistance of the elastic element 2, k2Lε is the resistance generated by the strain of the second fiber sensor 8, Δz is the axial deformation displacement of the elastic element 2, L is the grating length, and ε is the fiber strain.

[0098] The following is obtained through deformation compatibility conditions:

[0099]

[0100] And it is deduced that:

[0101]

[0102] Establishing fiber strain ε and F z The direct correlation.

[0103] Substituting ε into the FBG formula, we can finally establish F. z With wavelength offset Δλ B Quantitative relationship:

[0104]

[0105] When the ambient temperature does not change significantly, discard k. T The ΔT term is then used to calibrate the model using coefficients k1, k2, k. ε Axial force can be directly calculated from wavelength changes.

[0106] Figure 13 This demonstrates the working principle of fiber Bragg grating sensing for puncture force and shape-sensing puncture needles, such as... Figure 13 As shown, when the needle tip is simultaneously subjected to a lateral force F l and axial force F z At this time, the elastic element compensates for lateral displacement through micro-deformation and restricts lateral movement at the joint surface. The strain ε generated inside is transmitted to the FBG grating region of the fiber optic sensor 4; the modulator / demodulator monitors the wavelength offset Δλ of the FBG in real time. B Through a pre-established mathematical model, i.e., calibrating F z With Δλ BThe mapping relationship is finally solved to obtain the value of the axial puncture force F z .

[0107] During the puncture process, the puncture needle deforms due to interaction with the external environment, such as bronchial wall contact or needle puncture, so that the second FBG sensor 801 distributed on the first optical fiber sensor 5 generates a corresponding strain, and the FBG sensor located on the axial center line of the puncture needle 8 is not affected. Therefore, we can obtain the central wavelength change through the first optical fiber sensor 5, and solve the shape information on the continuous length through the existing algorithm to realize the shape sensing function.

[0108] The shape information helps the doctor to navigate and position, and avoids path deviation; the real-time puncture force feedback assists in judging the resistance of the needle tip contacting the tissue, and the combination of the two improves the puncture accuracy and safety. At the same time, the needle body ring groove structure collects tissue samples during the puncture process, realizing the integration of diagnosis and treatment.

[0109] Those skilled in the art can understand the present embodiment as a more specific description of embodiment 1.

[0110] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essential content of the present application. In the case of no conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other.

Claims

1. A fiber Bragg grating sensor enabled puncture force and shape sensing puncture needle, characterized in that, The needle body assembly and the sensing assembly are included; The needle body assembly is composed of a needle tip (1), an elastic element (2), a slotted needle body segment (3), a needle tail segment (4) and a hollow guide wire (6) which are coaxially connected in sequence; the elastic element (2) is bonded at both ends with the needle tip (1) and the slotted needle body segment (3) respectively; the hollow guide wire (6) is fused with the needle tail segment (4); The sensing assembly includes three first fiber optic sensors (5) which are distributed in the circumferential direction and a second fiber optic sensor (8) which is arranged in the axial direction.

2. The FBG-sensed puncture force and shape-aware puncture needle of claim 1, wherein, The rear part of the needle tip (1) is provided with a needle tip hole (103), a needle tip cylinder (102) and a needle tip groove (101); the elastic element (2) is of a hollow structure and is bonded at both ends with the needle tip (1) and the slotted needle body segment (3) respectively; the needle tip hole (103) is used for fixing the front end of the second fiber optic sensor (7).

3. The FBG-sensed puncture force and shape-aware puncture needle of claim 2, wherein, The slotted needle body segment (3) is provided with a side groove (301), a front groove (302) and a column hole (303); the side groove (301) is used for collecting tissue samples; the column hole (303) is connected with the needle tip cylinder (102) in cooperation.

4. The FBG-sensed puncture force and shape-aware puncture needle of claim 3, wherein, The needle tail segment (4) is provided with three sensor mounting grooves (401) which are uniformly distributed in the circumferential direction and a center through hole (402); the hollow guide wire (6) is fused with the needle tail segment (4).

5. The FBG-sensed puncture force and shape-aware puncture needle of claim 4, wherein, The first fiber optic sensor (5) is embedded in the needle tail end mounting groove (401); the first fiber optic sensor (5) is provided with a plurality of first FBG sensors (501) which are distributed at equal intervals.

6. The FBG-sensed puncture force and shape-aware puncture needle of claim 5, wherein, The front end of the second fiber optic sensor (8) is fixed in the needle tip hole (103); the second fiber optic sensor (8) is provided with two second FBG sensors (801); the second fiber optic sensor (8) extends through the needle body center through hole to the hollow guide wire (6); the second fiber optic sensor (8) extends to the inside of the hollow guide wire (6) through the center through holes (402) of the elastic element (2), the slotted needle body segment (3) and the needle tail segment (4) in sequence; the two second FBG sensors (801) are located at the front section of the fiber optic sensor and the rear section of the fiber optic sensor 4 respectively.

7. The FBG-sensed puncture force and shape-aware puncture needle of claim 6, wherein, The hollow guide wire (6) is provided with a fiber optic support (7) inside; the fiber optic support (7) is provided with a support hole (701) and three fiber optic positioning grooves (702) which are uniformly distributed in the circumferential direction; the three fiber optic positioning grooves (702) respectively fix the tail ends of the three first fiber optic sensors (5).

8. A method of sensing puncture force and shape using fiber Bragg grating sensors, comprising: The method applies the optical fiber Bragg grating sensing puncture force and shape sensing puncture needle as claimed in any one of claims 1-7, comprising: when the needle tip (1) is subjected to an axial force F z , the force transmission model satisfies: where λ B is the center wavelength of the reflected signal, Δλ B is the wavelength shift, P e is the strain-optic coefficient, ε is the fiber strain, α A is the thermal expansion coefficient, α n is the thermo-optic coefficient, ΔT is the change in temperature, k ε is the strain sensitivity coefficient, k T is the temperature sensitivity coefficient, k T ΔT is the temperature compensation term, k ε ε is the strain compensation term; The piercing needle is subjected to an axial force F z and a transverse force F l wherein the transverse force component has no effect on the optical fiber sensor (4) and only the axial force F z has an influence on the optical fiber sensor (4); When the puncture needle is subjected to an axial force F z the axial force F z is resolved into two parts: F z = k1Δz + k2Δz = k1Δz + k2Lε Wherein k1Δz corresponds to the deformation resistance of the elastic element (2), k2Lε is the resistance generated by the strain of the second fiber optic sensor (8), Δz is the axial deformation displacement of the elastic element (2), L is the grating length, and ε is the fiber strain; Through the deformation compatibility condition, the following is obtained: And deduce: A direct correlation between fiber strain ε and F z is established. Substitute ε into FBG formula, finally establish F z The quantitative relationship with wavelength shift Δλ B of the formula: When the ambient temperature changes little, the k T ΔT term, the model is calibrated by the coefficients k1, k2, k ε , directly from the wavelength changes to solve the axial force; When the needle tip is subjected to lateral force F l and axial force F z at the same time, the elastic element compensates for the lateral displacement through micro-deformation and limits the lateral movement with the joint surface, and the strain ε generated in the interior is transmitted to the FBG grating area of the optical fiber sensor (4); the wavelength shift Δλ B of the FBG is monitored in real time by the modulator-demodulator, and through the pre-established mathematical model, i.e., the mapping relationship between the calibration F z and Δλ B , the value of the axial puncture force F z is finally calculated.

9. The FBG-sensed puncture force and shape sensing method of claim 8, wherein, When the puncture needle deforms, the first FBG sensor (501) of the first fiber optic sensor (5) generates strain, and the three-dimensional shape is reconstructed through the distributed sensing algorithm.

10. The FBG-sensed puncture force and shape sensing method of claim 9, wherein, The side groove (301) of the slotted needle body segment (3) collects tissue samples during the puncture process.

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