Real-time path planning puncture device and method based on optical fiber deformation perception

Abstract

The invention relates to the technical field of medical instruments, in particular to a real-time path planning puncture device and method.The puncture needle is composed of an outer-layer sleeve and an inner-layer needle body, the inner needle body and the outer needle body are separated, optical fiber pollution is avoided, and three axial grooves are formed in the inner-layer needle body; each open groove is fixedly provided with one fiber grating sensor which is used for transmitting curvature changes on the advancing path of the puncture needle, the planned path can be updated in real time according to the curvature changes, and the puncture efficiency and accuracy are improved. The current three-dimensional curvature and instantaneous motion circle center coordinate data are updated in real time to draw a plurality of paths, after the current optimal path is determined according to a path scoring function, the mechanical arm is driven to enable the puncture needle to step by a preset distance according to the optimal path, wavelength drift data are repeatedly obtained to determine the optimal path of the next step, then the optimal path is stepped by the preset distance, and the optimal path of the next step is determined. The puncture accuracy is improved in a segmented stepping and optimal path updating mode.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to a real-time path planning puncture device and method based on optical fiber deformation sensing. Background Art

[0002] In clinical scenarios such as tumor biopsy and radioactive seed implantation, manual puncture highly relies on doctors' experience and has the following problems:

[0003] Insufficient accuracy: Affected by hand tremors and visual errors, the average puncture error reaches 3 - 5 mm (data source: Journal of Medical Imaging, 2023);

[0004] Operation fatigue: Long - term surgery easily leads to a decline in operation stability, and the secondary puncture rate is as high as 18% (data source: Clinical Radiology, 2022);

[0005] Radiation exposure: Dependent on real - time intraoperative CT / MRI guidance, the cumulative radiation dose of patients increases.

[0006] Therefore, finding a suitable method is a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0007] Based on this, it is necessary to propose a real - time path planning puncture device and method based on optical fiber deformation sensing to solve the problem of low puncture efficiency mentioned in the prior art.

[0008] In a first aspect, the present application provides a real - time path planning puncture device based on optical fiber deformation sensing, including:

[0009] A puncture needle, which is composed of an outer sleeve and an inner needle body nested coaxially. Three axial slots are evenly distributed circumferentially inside the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot. The measurement section of the fiber Bragg grating sensor is located in the front - end area of the puncture needle;

[0010] A six - degree - of - freedom robotic arm, with a puncture needle mounting interface at the end, and the mounting interface is used to connect with the puncture needle;

[0011] An optical fiber demodulator, which is provided with an optical connector and is connected to the fiber Bragg grating sensor for real - time calculation of the three - dimensional curvature data of the puncture needle;

[0012] A path planning module, which is used to receive the three - dimensional curvature data and plan a segmented needle - inserting path according to the three - dimensional curvature data, and update the path in real - time.

[0013] According to the real-time path planning puncture device based on optical fiber deformation perception provided by the present application, the beneficial effects are as follows: The puncture needle consists of an outer sleeve and an inner needle body. The design of separating the inner and outer needles avoids optical fiber contamination and supports repeated disinfection and use, reducing the clinical cost by about 60%. Three axial slots are provided in the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot, which is used to transmit the curvature change on the advancing path of the puncture needle, and can update the planned path in real time according to the curvature change, improving the puncture efficiency and accuracy.

[0014] In one embodiment, the depth of the slot is 0.1±0.02 mm, and the width of the slot is 0.15±0.3 mm.

[0015] In one embodiment, the outer sleeve is made of 316L stainless steel, the wall thickness of the outer sleeve is 0.1 mm, the inner needle body is made of nitinol alloy, and the bending stiffness of the puncture needle is ≤0.15 N·m 2 。

[0016] In the second aspect, the present application provides a real-time path planning method based on optical fiber deformation perception, which is used to apply the real-time path planning puncture device based on optical fiber deformation perception described in any item of the first aspect. The method includes:

[0017] Obtain a three-dimensional image, mark the target point according to the three-dimensional image; and determine the area that the puncture needle needs to avoid according to the three-dimensional image; the target point is the final end point reached by the puncture needle;

[0018] Drive the end of the robotic arm connected with the puncture needle to move to the initial position;

[0019] Obtain wavelength drift data through the fiber Bragg grating sensor, calculate the current three-dimensional curvature data of the front end of the puncture needle based on the wavelength drift data, and update the current instantaneous movement center coordinate data of the puncture needle according to the current three-dimensional curvature data;

[0020] Determine the path traveling strategy according to the area that needs to be avoided, and plan at least 3 paths based on the path traveling strategy with the current center as the basis;

[0021] Determine the optimal path from multiple paths according to the path scoring function, and drive the end of the robotic arm to step a preset distance in the direction of the optimal path;

[0022] After stepping the preset distance, repeat the steps of obtaining wavelength drift data through the fiber Bragg grating sensor to driving the end of the robotic arm to step a preset distance in the direction of the optimal path until the target point is reached.

[0023] In one embodiment, before the step of driving the end of the robotic arm connected with the puncture needle to move to the initial position, it further includes:

[0024] Automatically calibrate the initial wavelengths of three fiber Bragg grating sensors through an optical fiber demodulator, and establish a strain-wavelength mapping table.

[0025] In one embodiment, it is characterized in that the steps of obtaining wavelength drift data through a fiber Bragg grating sensor, calculating the current three-dimensional curvature data of the front end of the puncture needle based on the wavelength drift data, and updating the current puncture needle instantaneous movement center coordinate data according to the current three-dimensional curvature data include:

[0026] Obtain the wavelength drift data of each fiber Bragg grating sensor through three fiber Bragg grating sensors respectively, and calculate the three-dimensional curvature of the front end of the puncture needle according to the wavelength drift data of each fiber Bragg grating sensor; the calculation formula is as follows:

[0027]

[0028] where d is the vertical distance from the optical fiber to the neutral axis of the puncture needle, Δλ1 is the wavelength drift of the first fiber Bragg grating sensor; Δλ2 is the wavelength drift of the second fiber Bragg grating sensor; Δλ3 is the wavelength drift of the third fiber Bragg grating sensor; M is the optical fiber sensitivity coefficient;

[0029] The center coordinates (x c , y c ) are determined by the three-dimensional curvature (k x , k y ), and the formula is as follows:

[0030]

[0031] where θ is the current needle insertion direction angle, x tip is the real-time x-axis coordinate of the tip of the puncture needle, and y tip is the real-time y-axis coordinate of the tip of the puncture needle.

[0032] In one embodiment, the steps of determining a path traveling strategy according to the area to be avoided and planning at least 3 paths based on the current center include:

[0033] Divide the area to be avoided into a first area and a second area according to importance, the distance from the traveling path to the first area is at least greater than 3 mm, and the distance from the traveling path to the second area is at least greater than 80 mm;

[0034] Based on the current center coordinates (x c , y c ), generate radial paths at equal angular intervals; the rotation angle of the puncture needle corresponding to each path is θ i = θ current + i·Δ θ, where Δ θ = 10° to 30°, i = -1, 0, +1;

[0035] where, θ i is the offset angle of the generated candidate path, and θ current is the current needle insertion direction angle of the puncture needle.

[0036] In one embodiment, the step of determining the optimal path from multiple paths according to the path scoring function and driving the end of the robotic arm to step a preset distance in the optimal path direction includes:

[0037] The path scoring function is as follows:

[0038]

[0039] where, d min is the minimum distance between the candidate path and the area to be avoided, ΔL is the remaining distance from the end point of the path to the target point, and S is the path score;

[0040] Select the path with a higher path score as the optimal path direction.

[0041] In one embodiment, the determining of the path traveling strategy further includes:

[0042] When the path score is greater than or equal to the first preset score for multiple consecutive times, increase the next step distance;

[0043] When the path score is less than or equal to the second preset score for multiple consecutive times, reduce the next step distance.

[0044] In one embodiment, it further includes: stopping the step when the puncture needle reaches a position 0.8 mm to 1 mm away from the target point;

[0045] Or stopping the step when the number of steps of the puncture needle reaches 20 times.

[0046] According to the real-time path planning method based on optical fiber deformation perception provided by this application, the beneficial effects are as follows: The puncture needle consists of an outer sleeve and an inner needle body. The design of separating the inner and outer needles avoids optical fiber contamination, supports repeated disinfection and reuse, reduces the clinical cost by about 60%. Three axial slots are provided in the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot, which is used to transmit the curvature change on the advancing path of the puncture needle, and can update the planned path in real time according to the curvature change, improving the puncture efficiency and accuracy. In addition, by obtaining a three-dimensional image, marking the target point and the areas to be avoided according to the three-dimensional image, driving the robotic arm to move to the initial point, obtaining wavelength drift data through the fiber Bragg grating sensor, and updating the current three-dimensional curvature and the instantaneous motion center coordinate data in real time to draw multiple paths. After determining the current optimal path according to the path scoring function, driving the robotic arm to make the puncture needle step a preset distance according to the optimal path, and then repeating to obtain the wavelength drift data to determine the next optimal path and step the preset distance again. The puncture accuracy is improved by means of segmented stepping and updating the optimal path. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0048] Figure 1 It is a schematic structural diagram of a puncture needle in an embodiment;

[0049] Figure 2 It is a schematic diagram of the three-dimensional curvature decoupling principle in an embodiment;

[0050] Figure 3 It is a schematic diagram of the path planning process in an embodiment;

[0051] Figure 4 It is a schematic diagram of the path iteration process in an embodiment.

[0052] 101. Outer sleeve; 102. Inner needle body; 103. Slot; 104. Fiber Bragg grating sensor; 105. Curing glue; 106. Quick docking interface; 201. Robotic arm; 301. Fiber optic demodulator; 302. Optical connector; 401. Path planning module; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0053] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

[0054] Referring to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 As shown, in one of the embodiments, this application provides a real-time path planning puncture device based on optical fiber deformation sensing, including:

[0055] A puncture needle, which consists of an outer sleeve and an inner needle body nested coaxially. Three axial slots are evenly distributed circumferentially inside the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot. The measurement section of the fiber Bragg grating sensor is located in the front-end area of the puncture needle;

[0056] A six-degree-of-freedom robotic arm, with a puncture needle mounting interface at the end, and the mounting interface is used to connect to the puncture needle;

[0057] An optical fiber demodulator, which is provided with an optical connector and is connected to the fiber Bragg grating sensor for real-time calculation of the three-dimensional curvature data of the puncture needle;

[0058] A path planning module, which is used to receive the three-dimensional curvature data and plan a segmented needle insertion path according to the three-dimensional curvature data, and update the path in real time.

[0059] The existing automatic puncture systems face two major technical bottlenecks in sensing and planning. First is the problem of sensor integration. The diameter of the puncture needle is usually less than 1 mm. For example, the diameter of a 22G puncture needle is 0.7 mm, and traditional force sensors or displacement sensors (such as strain gauges, piezoelectric films) cannot be integrated due to size limitations. Secondly, the existing puncture needle solutions use a single fiber optic sensor to replace the needle core, which can only detect the curvature of a single plane and cannot decouple three-dimensional deformations. Moreover, the existing path planning does not consider the error accumulation caused by multiple needle insertions, the interpolation algorithm fails, and traditional modeling methods use the finite element method or biomechanical models to predict the trajectory of the puncture needle (such as patent CN108577977A), which requires input of complex parameters such as tissue elastic modulus and friction coefficient, and is relatively complex, resulting in a calculation delay of more than 500 ms and unable to meet the real-time control requirements.

[0060] In summary, the existing technologies cannot meet the requirements of miniaturization while ensuring precision, that is, there is a contradiction between sensing precision and miniaturization. Miniature sensors such as fiber Bragg gratings (FBGs) can achieve integration on needles, but a single sensor cannot meet the requirements of three-dimensional deformation decoupling. In addition, complex mechanical models have high prediction accuracy but time-consuming calculations, while simplified models have strong real-time performance but serious error accumulation. The current technologies cannot ensure real-time performance while meeting precision requirements.

[0061] It should be noted that for the real-time path planning puncture device based on fiber optic deformation perception provided in this embodiment, the beneficial effects are as follows: The puncture needle consists of an outer sleeve and an inner needle body. The design of separating the inner and outer needles avoids fiber optic contamination, supports repeated disinfection and reuse, and reduces the clinical cost by about 60%. Three axial slots are provided in the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot, which is used to transmit the curvature change on the traveling path of the puncture needle, and can update the planned path in real time according to the curvature change, improving the puncture efficiency and accuracy.

[0062] Specifically, three fiber Bragg grating sensors are distributed along the axis of the puncture needle at 120°. Combining the nested structure of the inner and outer needles, real-time decoupling of three-dimensional deformation is achieved, with an accuracy of ±1mm. And based on the curvature feedback, an arc segment iterative algorithm is involved. By dynamically generating candidate paths and optimizing the scores, the safety and efficiency are improved, and real-time obstacle avoidance navigation for soft tissue puncture is realized. Clinical tests show that the error of this device is reduced by 50% (≤1mm) compared with the existing technologies, and it is applicable to scenarios such as tumor biopsy and particle implantation, significantly improving the safety and efficiency.

[0063] It should be noted that a quick docking interface is provided at the proximal end of the inner needle body, which supports blind plug-in connection with the optical connector of the fiber optic demodulator.

[0064] The path planning module of this embodiment receives the three-dimensional curvature data calculated by the fiber optic demodulation instrument, and receives the area to be avoided required for planning the obstacle map of the medical image. Based on the quintic spline interpolation, the three-dimensional shape of the front end of the puncture needle is reconstructed. According to the current three-dimensional curvature, the instantaneous motion center coordinates are calculated, and N candidate paths (N≥3) are generated in combination with the area to be avoided. The path with the highest path score is selected, and the robotic arm is driven to rotate the puncture needle to a new direction and advance direction, and the single needle insertion step distance ≤5mm.

[0065] For the real-time path planning puncture device based on fiber optic deformation perception provided in this application, the beneficial effects are as follows: The puncture needle consists of an outer sleeve and an inner needle body. The design of separating the inner and outer needles avoids fiber optic contamination, supports repeated disinfection and reuse, and reduces the clinical cost by about 60%. Three axial slots are provided in the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot, which is used to transmit the curvature change on the traveling path of the puncture needle, and can update the planned path in real time according to the curvature change, improving the puncture efficiency and accuracy.

[0066] In one embodiment, the depth of the slotted groove is 0.2 ± 0.02 mm, and the width of the slotted groove is 0.25 ± 0.3 mm.

[0067] In one embodiment, the outer sleeve is made of 316L stainless steel, the wall thickness of the outer sleeve is 0.1 mm, the inner needle body is made of nitinol alloy, and the bending stiffness of the puncture needle is ≤ 0.15 N·m 2 。

[0068] It should be noted that this embodiment provides a nested design of inner and outer needles. The outer sleeve is a sterile sleeve made of 316L stainless steel, the wall thickness of the outer needle is 0.1 mm, and the outer sleeve is for single use; the inner needle body is made of nitinol alloy and the inner needle body can be reused. Three slotted grooves (groove depth 0.2 mm, width 0.25 mm) are evenly distributed along the axis at 120° on the surface of the seedling, and three FBG optical fibers are embedded, with the FBG diameter being 0.125 mm; the sensitive element part of the sensor is at the front end of 50 mm, and the bending stiffness of the puncture needle is ≤ 0.15 N·m 2 UV curable glue is filled in the slotted groove and polished to a surface roughness Ra ≤ 0.8 μm.

[0069] Regarding puncture accuracy

[0070] Laboratory test: The puncture error of the porcine liver tissue is ≤ 1 mm (n = 50 times), which is 50% higher than that of the existing automatic system (2 mm);

[0071] Clinical comparison: Compared with the Da Vinci puncture module, the tumor hit rate has increased from 78% to 95% (data source: controlled trial in a cooperative hospital).

[0072] Real-time optimization:

[0073] The single-step planning time is ≤ 50 ms (the traditional finite element model > 500 ms), meeting the requirements of the dynamic deformation response of soft tissues;

[0074] The number of intraoperative image scans has been reduced from an average of 8 times to 3 times (the radiation dose is reduced by 62%).

[0075] Regarding clinical value

[0076] Benefits to patients: The secondary puncture rate has been reduced from 18% to 5%, reducing tissue damage; the operation time has been shortened by 35% (from 45 minutes to 29 minutes).

[0077] Simplified operation: The automatic obstacle avoidance function reduces the number of manual interventions by doctors and reduces the learning curve; it supports MRI-compatible design (no metal interference for optical fibers), expanding to the brain puncture scenario.

[0078] Regarding industrialization advantages

[0079] Cost control: The design of reusing inner needles reduces the cost of consumables for a single operation by 40% (from $200 to $120); the modular design of the fiber optic demodulator can adapt to various types of puncture needles.

[0080] In one embodiment, the present application provides a real-time path planning method based on fiber optic deformation sensing, which is used for the real-time path planning puncture device based on fiber optic deformation sensing described in any one of the first aspects. The method includes:

[0081] Step S101: Obtain a three-dimensional image, mark the target point according to the three-dimensional image; and determine the area that the puncture needle needs to avoid according to the three-dimensional image; the target point is the end point that the puncture needle finally reaches.

[0082] Step S102: Drive the end of the robotic arm connected with the puncture needle to move to the initial position.

[0083] Step S103: Obtain wavelength drift data through a fiber Bragg grating sensor, calculate the current three-dimensional curvature data of the front end of the puncture needle based on the wavelength drift data, and update the current instantaneous movement center coordinate data of the puncture needle according to the current three-dimensional curvature data.

[0084] Step S104: Determine a path traveling strategy according to the area that needs to be avoided, and plan at least 3 paths based on the current center based on the path traveling strategy.

[0085] Step S105: Determine the optimal path from multiple paths according to a path scoring function, and drive the end of the robotic arm to step a preset distance in the direction of the optimal path.

[0086] Step S106: After stepping the preset distance, repeat the steps of obtaining wavelength drift data through the fiber Bragg grating sensor until the step of driving the end of the robotic arm to step a preset distance in the direction of the optimal path until the target point is reached.

[0087] It should be noted that preprocess the three-dimensional image, plan the position of the target tissue to determine the target point, such as the position of the tumor, divide the avoidance area, such as marking dangerous areas such as blood vessels, nerves, and large arteries, and mark the target point coordinates and obstacle avoidance areas in the three-dimensional image. In addition to segmentally stepping the puncture needle, based on the quintic spline interpolation algorithm, the three-dimensional coordinates of the front end of the puncture needle are reconstructed at intervals of 10 mm, and the maximum error is <0.3 mm.

[0088] The real-time path planning method based on optical fiber deformation perception provided by the present application has the beneficial effects that the puncture needle consists of an outer sleeve and an inner needle body. The design of separating the inner and outer needles avoids optical fiber contamination and supports repeated disinfection and use, reducing the clinical cost by about 60%. Three axial slots are provided in the inner needle body, and a fiber Bragg grating sensor is fixedly arranged in each slot for transmitting the curvature change on the advancing path of the puncture needle, and the planned path can be updated in real time according to the curvature change, improving the puncture efficiency and accuracy. In addition, by acquiring a three-dimensional image, marking the target point and the areas to be avoided according to the three-dimensional image, driving the robotic arm to move to the initial position, acquiring wavelength drift data through the fiber Bragg grating sensor, and updating the current three-dimensional curvature and the instantaneous motion center coordinate data in real time to draw multiple paths. After determining the current optimal path according to the path scoring function, driving the robotic arm to make the puncture needle step a preset distance according to the optimal path, and then repeating to acquire the wavelength drift data to determine the next optimal path and step the preset distance again, improving the puncture accuracy by means of segmented stepping and updating the optimal path.

[0089] In one embodiment, before the step of moving the end of the robotic arm driving the puncture needle to the initial position, it further includes:

[0090] Automatically calibrating the initial wavelengths of the three fiber Bragg grating sensors through an optical fiber demodulator and establishing a strain-wavelength mapping table.

[0091] It should be noted that the optical fiber demodulator automatically calibrates the initial wavelengths of the FBGs, and the initial wavelengths of the three FBGs are 1510 nm, 1520 nm, and 1530 nm respectively.

[0092] In one embodiment, it is characterized in that the step of acquiring wavelength drift data through the fiber Bragg grating sensor, calculating the current three-dimensional curvature data of the front end of the puncture needle based on the wavelength drift data, and updating the current instantaneous motion center coordinate data of the puncture needle according to the current three-dimensional curvature data includes:

[0093] Acquiring the wavelength drift data of each fiber Bragg grating sensor through the three fiber Bragg grating sensors respectively, and calculating the three-dimensional curvature of the front end of the puncture needle according to the wavelength drift data of each fiber Bragg grating sensor; the calculation formula is as follows:

[0094]

[0095] Wherein, d is the vertical distance from the optical fiber to the neutral axis of the puncture needle, Δλ1 is the wavelength drift of the first fiber Bragg grating sensor; Δλ2 is the wavelength drift of the second fiber Bragg grating sensor; Δλ3 is the wavelength drift of the third fiber Bragg grating sensor; M is the optical fiber sensitivity coefficient.

[0096] Center coordinate (x c , y c)Determined by three-dimensional curvature (k x , k y ), and the formula is as follows:

[0097]

[0098] where θ is the current needle insertion direction angle, x tip is the real-time x-axis coordinate of the tip of the puncture needle, and y tip is the real-time y-axis coordinate of the tip of the puncture needle.

[0099] In one embodiment, the step of determining a path travel strategy according to the area to be avoided and planning at least 3 paths based on the current center point according to the path travel strategy includes:

[0100] Dividing the area to be avoided into a first area and a second area according to importance, with the distance from the travel path to the first area being at least greater than 3 mm and the distance from the travel path to the second area being at least greater than 80 mm;

[0101] Based on the current center point coordinates (x c , y c ), generating radial paths at equal angular intervals; the rotation angle of the puncture needle corresponding to each path is θ i = θ current + i·Δ θ , where Δ θ = 10° - 30°, i = -1, 0, +1;

[0102] where θ i is the offset angle of the generated candidate path, and θ current is the current needle insertion direction angle of the puncture needle;

[0103] Specifically, the current needle insertion direction angle of the puncture needle is the deflection angle relative to the initial path.

[0104] In one embodiment, the step of determining the optimal path from multiple paths according to the path scoring function and driving the end of the robotic arm to step a preset distance in the optimal path direction includes:

[0105] The path scoring function is as follows:

[0106]

[0107] where d min is the minimum distance between the candidate path and the area to be avoided, ΔL is the remaining distance from the end point of the path to the target point, and S is the path score;

[0108] Selecting the path with a higher path score as the optimal path direction.

[0109] Example 1: Liver Tumor Biopsy Surgery

[0110] Equipment Configuration: Puncture Needle Assembly: The inner needle (nitinol, diameter 0.5 mm, slot depth 0.2 ± 0.02 mm, slot width 0.25 ± 0.3 mm) is embedded with three FBG optical fibers (wavelength range 1510 - 1590 nm), and the outer cannula (316L stainless steel, wall thickness 0.1 mm); Robotic Arm: A six-degree-of-freedom collaborative robotic arm (repeat positioning accuracy ±0.05 mm), with a puncture needle clamp installed at the end; Control Terminal: An integrated fiber optic demodulator (sampling rate 1 kHz) and path planning software;

[0111] Connect the puncture needle to the robotic arm, obtain three-dimensional images through MRI, mark the target (target diameter 10 mm) and the surrounding vascular exclusion zones (minimum interval ≥ 3 mm); The path planning software generates an initial needle insertion path (linear distance 80 mm, avoiding large blood vessels); Insert the inner needle into the sterile outer cannula and connect it to the end of the robotic arm through a quick-release interface; The fiber optic demodulator automatically calibrates the initial wavelengths of the FBGs (1510 nm, 1520 nm, 1530 nm) and establishes a strain-wavelength mapping table;

[0112] The robotic arm moves to the initial site, which is marked on the skin surface. The angle between the puncture needle and the skin is adjusted to 30°. Use ultrasound to verify the needle insertion point and the target orientation, with an error < 1 mm. Perform cyclic segmented needle insertion and path correction, and update the path in real time.

[0113] The segmented needle insertion and path correction are as follows:

[0114] a. Data Acquisition

[0115] The fiber optic demodulator reads the wavelength drifts of the three FBGs: Δλ1 = 0.5 nm, Δλ2 = 0.3 nm, Δλ3 = 0.8 nm; Calculate the curvature according to the formula:

[0116]

[0117] In this example, the vertical distance d from the optical fiber to the neutral axis of the puncture needle is 0.2 mm, and the fiber sensitivity coefficient M is 0.6 pm / με.

[0118] b. Shape Reconstruction: Use fifth-order spline interpolation to generate the three-dimensional coordinates 60 mm in front of the needle tip, with a maximum fitting error of 0.2 mm;

[0119] c. Path Generation: Calculate the instantaneous center coordinates (x c = 12.5 mm, y c = -3.2 mm); Generate 3 candidate paths (angle offsets -15°, 0°, +15°), and calculate the scores as shown in Table 1 below:

[0120] Path d_min (mm) ΔL (mm) Score (S) -15° 2.1 18.3 0.72 0° 1.5 17.8 0.65 +15° 3.0 20.1 0.85

[0121] d. Execute the decision: Select the +15° path, rotate the robotic arm by 15° and advance the puncture needle by 5 mm; Update the remaining distance to the target to 20.1 mm.

[0122] Termination condition: After the 15th needle insertion, the tip of the needle is 0.8 mm from the target, triggering termination; The biopsy needle extends to collect tissue samples, and the whole process takes 22 minutes.

[0123] Postoperative verification

[0124] CT scan confirms that the needle tip position error is 0.7 mm and the vascular no-go zone is not touched; The pathological examination of the sample confirms hepatocellular carcinoma.

[0125] The solution provided in this example updates the path in real time by segmental needle insertion, improving safety and accuracy.

[0126] Example 2 Prostate radioactive seed implantation

[0127] 1. Adaptation to scenario differences

[0128] Puncture needle adjustment: Use an extended inner needle (total length), and extend the optical fiber measurement section to the front end;

[0129] Path planning parameters: Adjust the scoring function weights to (prioritize avoiding the urethra and nerve bundles); Reduce the step size to (due to high prostate tissue density, fine control is required).

[0130] 2. Surgical procedure

[0131] Intraoperative imaging: Update the three-dimensional prostate model (accuracy) in real time with transrectal ultrasound;

[0132] Dynamic obstacle avoidance: When the needle tip is close to the urethra, the algorithm generates a path with a reverse rotation of 30°, and the safety score is increased to 0.9; Finally, 12 seeds are implanted, with an average position error and no damage to the nerve bundle.

[0133] Example 3 Deep brain electrode implantation (MRI-compatible scenario)

[0134] 1. Special design

[0135] Puncture needle material: Replace the outer cannula with ceramic material (magnetic susceptibility), and the inner needle is made of PEEK plastic;

[0136] Optical fiber demodulator: Use the 1550 nm band to avoid interference with MRI radio frequency signals.

[0137] 2. Intraoperative procedure

[0138] Multi-modal navigation: Preoperative MRI plans the target (ventral intermediate nucleus of the thalamus), and intraoperative O-arm real-time images are fused; Optical fiber sensing data and image registration error;

[0139] Result: Electrode implantation error, and the improvement rate of postoperative tremor symptoms was 92%.

[0140] In one of the embodiments, the determining path traveling strategy further includes:

[0141] When the path scores are greater than or equal to the first preset score for multiple consecutive times, increase the next stepping distance;

[0142] When the path scores are less than or equal to the second preset score for multiple consecutive times, reduce the next stepping distance.

[0143] It should be noted that when the path score S ≥ 0.8 for 3 consecutive times, increase the next stepping distance to 7 mm, and when the score S ≤ 0.5, reduce the next step length to 2 mm.

[0144] In one of the embodiments, it further includes: when the puncture needle reaches a position 0.8 mm to 1 mm away from the target point, stop stepping;

[0145] Or when the number of steps of the puncture needle reaches 20 times, stop stepping.

[0146] It should be noted that the puncture needle can be stopped when it reaches the target point position, or it can be selected to stop stepping at a position 0.8 mm to 1 mm away from the target point, or when the number of steps of the puncture needle reaches 20 times to stop stepping, to prevent over-puncturing.

[0147] It should be noted that when an element is referred to as "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly disposed on the other component; when a component is referred to as "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0148] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meanings of "multiple" and "several" are two or more, unless otherwise specifically defined.

[0149] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limited conditions under which the present application can be implemented. Therefore, they do not have technical substance significance. Any modification of the structure, change of the ratio relationship, or adjustment of the size, without affecting the effects that the present application can produce and the purposes that can be achieved, should still fall within the scope that can be covered by the technical content disclosed in the present application.

[0150] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0151] The above-described embodiments merely represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A real-time path planning puncture device based on optical fiber deformation perception, characterized in that: include: The puncture needle is composed of an outer sleeve and an inner needle body coaxially nested, the inner needle body has three axial slots evenly distributed in the circumference, a fiber grating sensor is fixedly arranged in each slot, and the measuring section of the fiber grating sensor is located in the front end area of ​​the puncture needle; A six-degree-of-freedom robotic arm, with a puncture needle mounting interface at the end, the mounting interface being used to connect with the puncture needle; An optical fiber demodulator is provided with an optical connector and connected to the optical fiber grating sensor to calculate the three-dimensional curvature data of the puncture needle in real time; The path planning module is used to receive the three-dimensional curvature data, plan a segmented needle insertion path according to the three-dimensional curvature data, and update the path in real time.

2. The real-time path planning puncture device based on optical fiber deformation sensing according to claim 1 is characterized in that: The depth of the groove is 0.2±0.02 mm, and the width of the groove is 0.25±0.3 mm.

3. The real-time path planning puncture device based on optical fiber deformation sensing according to claim 1 is characterized in that: The outer sleeve is made of 316L stainless steel, the wall thickness of the outer sleeve is 0.1mm, the inner needle body is made of nickel-titanium alloy, and the bending stiffness of the puncture needle is ≤0.15N·m 2 .

4. A real-time path planning method based on optical fiber deformation perception, characterized in that: The method for applying the real-time path planning puncture device based on optical fiber deformation perception according to any one of claims 1 to 3 comprises: Acquire a three-dimensional image, mark a target point according to the three-dimensional image; and determine an area that the puncture needle needs to avoid according to the three-dimensional image; the target point is the final destination of the puncture needle; Driving the end of the robotic arm connected with the puncture needle to move to the initial point; Acquire wavelength drift data through a fiber grating sensor, calculate current three-dimensional curvature data of the front end of the puncture needle based on the wavelength drift data, and update the coordinate data of the center of the instantaneous motion of the puncture needle according to the current three-dimensional curvature data; Determine a path moving strategy according to the area to be avoided, and plan at least three paths based on the path moving strategy based on the current center of the circle; Determine the optimal path from multiple paths according to the path scoring function, and drive the end of the robot arm to step a preset distance in the direction of the optimal path; After stepping the preset distance, the step of acquiring wavelength drift data by the fiber grating sensor is repeated until the end of the driving mechanical arm steps the preset distance in the optimal path direction until the target point is reached.

5. The real-time path planning method based on optical fiber deformation perception according to claim 4 is characterized in that: Before the step of driving the end of the mechanical arm connected with the puncture needle to move to the initial point, the method further includes: The initial wavelengths of three fiber grating sensors are automatically calibrated by a fiber demodulator, and a strain-wavelength mapping table is established.

6. The real-time path planning method based on optical fiber deformation perception according to claim 5 is characterized in that: The steps of acquiring wavelength drift data through a fiber grating sensor, calculating the current three-dimensional curvature data of the front end of the puncture needle based on the wavelength drift data, and updating the coordinate data of the center of the instantaneous motion of the puncture needle according to the current three-dimensional curvature data include: The wavelength drift data of each fiber grating sensor is obtained through three fiber grating sensors respectively, and the three-dimensional curvature of the front end of the puncture needle is solved according to the wavelength drift data of each fiber grating sensor; the solving formula is as follows: Wherein, d is the vertical distance between the optical fiber and the neutral axis of the puncture needle, Δλ1 is the wavelength drift of the first fiber grating sensor; Δλ2 is the wavelength drift of the second fiber grating sensor; Δλ3 is the wavelength drift of the third fiber grating sensor; M is the fiber sensitivity coefficient; The coordinates of the center of the circle (x c ,y c ) is given by the three-dimensional curvature (k x ,k y ) is determined by the following formula: Among them, θ is the current needle direction angle, ); x tip is the real-time x-axis coordinate of the puncture needle tip, y tip The real-time y-axis coordinate of the puncture needle tip.

7. The real-time path planning method based on optical fiber deformation perception according to claim 5 is characterized in that: The step of determining a path moving strategy according to the area to be avoided, and planning at least three paths based on the path moving strategy based on the current center of the circle comprises: The areas to be avoided are divided into a first area and a second area according to their importance, and the distance from the first area on the travel path is at least greater than 3 mm, and the distance from the second area on the travel path is at least greater than 80 mm; The current center coordinate (x c ,y c ) as the reference, radial paths are generated at equal angle intervals; the rotation angle of the puncture needle corresponding to each path is θ i =θ current +i·Δ θ , where Δx = 10°~30°, i = -1, 0, +1; Among them, θi is the offset angle of the generated candidate path, θ current It is the current insertion direction angle of the puncture needle.

8. The real-time path planning method based on optical fiber deformation perception according to claim 5 is characterized in that: The step of determining the optimal path from the multiple paths according to the path scoring function and driving the end of the robot arm to step a preset distance in the direction of the optimal path comprises: The path scoring function is as follows: Among them, d min is the minimum distance between the candidate path and the area to be avoided, ΔL is the remaining distance from the end point of the path to the target, and S is the path score; The path with a higher path score is selected as the optimal path direction.

9. The real-time path planning method based on optical fiber deformation perception according to claim 7, characterized in that: The path determination strategy also includes: When the path score is greater than or equal to the first preset score for multiple consecutive times, increase the next step distance; When the path scores are less than or equal to the second preset score for multiple consecutive times, the next stepping distance is reduced.

10. The real-time path planning method based on optical fiber deformation perception according to claim 8, characterized in that: Also includes: When the puncture needle reaches 0.8mm to 1mm from the target point, it stops moving; Or when the puncture needle steps 20 times, the stepping stops.

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