Preparation method of microcatheter

Abstract

The invention provides a preparation method of a microcatheter, which comprises the following steps: using a mathematical model to predict the deformation of a far-end actuator in the microcatheter to obtain a first theoretical result, the far-end actuator comprising a polyethylene substrate and a memory alloy coil; establishing a finite element model by using a finite element method, and simulating deformation of the far-end actuator by using the finite element model to obtain a first simulation result; comparing the first theoretical result with the first simulation result to obtain the goodness of fit between the first theoretical result and the first simulation result; and in response to the condition that the goodness of fit meets a preset requirement, batch preparation of the micro-catheters is performed according to the parameters of the micro-catheters. Through establishment and analysis of a finite element model, the accuracy of a mathematical model in the aspect of quickly predicting and optimizing a microcatheter far-end actuator is verified, an active microcatheter driven by the shape memory effect can be conveniently designed and optimized, and effective guidance and navigation can be conveniently carried out in interventional operations of cardiovascular and cerebrovascular diseases.

Description

Technical Field

[0001] The present application belongs to the field of medical equipment, and specifically relates to a method for preparing a microcatheter. Background Art

[0002] In recent years, cardiovascular and cerebrovascular diseases have become a major threat to human life and health. Although existing continuous robots have shown great potential in the field of interventional surgery, most existing continuous robots are limited in their functions in complex vascular chambers. Therefore, researchers have proposed various active microcatheters and adaptive driving methods to solve this problem. However, the theoretical modeling of these microcatheters has not been solved.

[0003] There is an urgent need to design and optimize active microcatheters driven by the shape memory effect for effective guidance and navigation during interventional procedures for cardiovascular and cerebrovascular diseases. Summary of the invention

[0004] The present application provides a method for preparing a microcatheter to solve the problem that the microcatheter cannot be effectively optimized at present.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a method for preparing a microcatheter, the preparation method comprising: using a mathematical model to predict the deformation of a distal actuator in a microcatheter to obtain a first theoretical result, the distal actuator comprising a polyethylene substrate and a memory alloy coil; using a finite element method to establish a finite element model, and using the finite element model to simulate the deformation of the distal actuator to obtain a first simulation result; comparing the first theoretical result with the first simulation result to obtain a degree of fit between the first theoretical result and the first simulation result; in response to the degree of fit meeting a preset requirement, batch preparation of microcatheters is performed using the parameters of the microcatheter.

[0006] The step of using a mathematical model to predict the deformation of the distal actuator in the microcatheter to obtain a first theoretical result includes: determining the negative thermal strain of the memory alloy coil according to the following formula:

[0007]

[0008] Wherein, εo represents the negative thermal strain of the memory alloy coil, represents the maximum residual strain of the detwinned memory alloy coil; and determines the first theoretical result of the remote actuator according to the negative thermal strain of the memory alloy coil.

[0009] Among them, the step of establishing a finite element model using the finite element method includes: simplifying the remote actuator into a polyethylene substrate embedded with two memory alloy coils; driving the elastic polyethylene substrate to deform, and recording the tip displacement of the remote actuator and the deformation of the polyethylene substrate, and establishing a first relationship between the tip displacement and curvature of the remote actuator; wherein, the step of simulating the deformation of the remote actuator using the finite element model to obtain a first simulation result includes: simulating the tip displacement of the remote actuator using the finite element model, and determining the curvature of the remote actuator based on the first relationship established in advance.

[0010] Among them, the step of establishing a finite element model using the finite element method also includes: setting the constraint between the polyethylene substrate and the memory alloy coil in the finite element model as a binding constraint; its boundary condition is that one end is a fixed end and the other end is a free end; a thermal field with the same temperature as the surface temperature of the austenite in the memory alloy coil is loaded on the finite element model to incorporate temperature-displacement coupling.

[0011] Among them, the step of comparing the first theoretical result with the first simulation result to obtain the degree of fit between the first theoretical result and the first simulation result includes: comparing the first curvature corresponding to the first theoretical result with the second curvature corresponding to the first simulation result to obtain the difference between the first curvature and the second curvature; determining the degree of fit between the first theoretical result and the first simulation result according to the difference between the first curvature and the second curvature, wherein the degree of fit is inversely proportional to the difference.

[0012] The step of simulating the tip displacement of the distal actuator by using the finite element model and determining the curvature of the distal actuator according to the first relationship established in advance includes: obtaining the curvature of the distal actuator according to the following formula:

[0013]

[0014] Among them, the deformation parameter is R S , the tip length of the distal actuator is L, Δx is the length of the orthographic projection of the tip position on the side away from the fixed end, and Δy is the difference between the tip length L of the distal actuator and the displacement of the distal actuator tip on the Y axis after deformation.

[0015] Among them, the preparation method also includes: changing the residual strain of the memory alloy coil, the residual strain is selected in the range of 0-5%; obtaining the first theoretical result of the remote actuator from the mathematical model; and obtaining the first simulation result of the remote actuator from the finite element model.

[0016] The preparation method further includes: using the polyethylene substrate with the same radius to change the offset position of the memory alloy coil; obtaining a first theoretical result of the remote actuator from the mathematical model; and obtaining a first simulation result of the remote actuator from the finite element model.

[0017] The preparation method further includes: using the memory alloy coil with the same diameter to change the radius of the polyethylene substrate; obtaining a first theoretical result of the remote actuator from the mathematical model; and obtaining a first simulation result of the remote actuator from the finite element model.

[0018] The method further includes: preparing the distal actuator: selecting the memory alloy coil of a first diameter and the polyethylene substrate of a second inner diameter; detwisting the memory alloy coil; placing the memory alloy coil in a biased manner in a steel mold; injecting liquid polyethylene into the mold and solidifying it; removing the solidified polyethylene substrate and the memory alloy coil from the mold; and combining the distal actuator and the polyethylene catheter to obtain a microcatheter.

[0019] The beneficial effects of the present application are: in the present application, a mathematical model is used to predict the deformation of a distal actuator in a microcatheter to obtain a first theoretical result, a finite element method is used to establish a finite element model, and the finite element model is used to simulate the deformation of the distal actuator to obtain a first simulation result; the first theoretical result and the first simulation result are compared to obtain a degree of agreement between the first theoretical result and the first simulation result; in response to the degree of agreement meeting a preset requirement, the accuracy of the mathematical model in rapidly predicting and optimizing the distal actuator of the microcatheter is verified, which facilitates the design and optimization of active microcatheters driven by shape memory effects, so as to provide effective guidance and navigation in interventional surgeries for cardiovascular and cerebrovascular diseases. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0021] Figure 1 It is a schematic flow chart of an embodiment of a method for preparing a microcatheter in the present application;

[0022] Figure 2 yes Figure 1 A schematic diagram of a flow chart of an embodiment of step S20;

[0023] Figure 3 yes Figure 2 A schematic diagram of a structure of an embodiment of obtaining the curvature in step S23;

[0024] Figure 4 yes Figure 1 A schematic diagram of a flow chart of an embodiment of step S30;

[0025] Figure 5 yes Figure 1 A schematic diagram of a flow chart of an embodiment before step S10;

[0026] Figure 6 yes Figure 5 Schematic diagram of the results of step S252 and step S253 in an embodiment;

[0027] Figure 7 yes Figure 1 A schematic diagram of a flow chart of another embodiment before step S10;

[0028] Figure 8 yes Figure 7 Schematic diagram of the results of step S255 and step S256 in an embodiment;

[0029] Fig. 9 yes Figure 1 A schematic diagram of a flow chart of another embodiment before step S10;

[0030] Fig.10 yes Fig. 9 Schematic diagram of the results of step S258 and step S259 in an embodiment;

[0031] Fig.11 yes Figure 1 FIG. 1 is a flow chart of an embodiment of preparing a microcatheter before step S10. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0033] See also Figure 1 The present application provides a method for preparing a microcatheter, the method comprising:

[0034] S10: A mathematical model was used to predict the deformation of the distal actuator in the microcatheter, and the first theoretical results were obtained. The distal actuator includes a polyethylene substrate and a memory alloy coil.

[0035] Specifically, a mathematical model is established, which is established according to the deformation characteristics of the distal actuator in the microcatheter, and the first theoretical result is obtained through the mathematical model. Among them, the distal actuator includes an elastic polyethylene substrate and a memory alloy coil, and the memory alloy coil includes a U-shaped shape memory alloy coil. The distal actuator has reconfigurability, and this performance is mainly determined by the shape memory effect of the memory alloy coil and the thermal mismatch effect between the memory alloy coil and the polyethylene substrate. At the same time, the microcatheter has a reconfigurable distal actuator, which can achieve effective navigation and interventional surgery through the shape memory effect.

[0036] S20: Using the finite element method to establish a finite element model, and using the finite element model to simulate the deformation of the remote actuator to obtain a first simulation result.

[0037] Specifically, the finite element model can perform not only static analysis but also dynamic analysis. During the deformation of the distal actuator, the finite element model can simulate the process to obtain a first simulation result. Among them, the bending process of the microcatheter can be simulated using ABAQUS finite element software.

[0038] S30: Compare the first theoretical result and the first simulation result to obtain a degree of agreement between the first theoretical result and the first simulation result.

[0039] Specifically, by comparing the first theoretical result with the first simulation result, the difference between the first theoretical result and the first simulation result can be obtained, and then the degree of agreement between the first theoretical result and the first simulation result can be determined.

[0040] S40: In response to the fit satisfying the preset requirement, batch preparation of microcatheters is performed according to the parameters of the microcatheters.

[0041] Specifically, it is determined whether the degree of fit meets the preset requirements. When the degree of fit meets the preset requirements, the accuracy of the mathematical model is verified, and batch preparation can be performed according to the parameters of the microcatheter.

[0042] In one embodiment, step S10 includes:

[0043] S11: Determine the negative thermal strain of the memory alloy coil according to the following formula:

[0044]

[0045] Where, εo represents the negative thermal strain of the memory alloy coil, It represents the maximum residual strain of the detwinned memory alloy coil. The memory alloy coil is a type of shape memory alloy. Its deformation is related to many factors, among which negative thermal strain is an important property. Shape memory alloys will undergo phase change when the temperature changes, resulting in a change in shape. The relationship between negative thermal strain and the maximum residual strain of detwinned alloys satisfies the above formula.

[0046] S12: Determine a first theoretical result of the remote actuator according to the negative thermal strain of the memory alloy coil.

[0047] Specifically, according to the negative thermal strain of the memory alloy coil, the first theoretical result of the remote actuator is determined.

[0048] In one embodiment, see Figure 2 In step S20, the step of establishing a finite element model using the finite element method includes:

[0049] S21: The remote actuator is simplified to a polyethylene substrate embedded with two memory alloy coils.

[0050] Specifically, the remote actuator was simplified into a polyethylene substrate embedded with two memory alloy coils, which facilitated the construction of the finite element model.

[0051] After step S21, the method further includes:

[0052] S211: The constraint between the polyethylene substrate and the memory alloy coil in the finite element model is set as a binding constraint; its boundary condition is that one end is a fixed end and the other end is a free end.

[0053] Specifically, the constraint mode between the polyethylene substrate and the memory alloy coil in the finite element model is set as a binding constraint to simulate the actual usage, in which one end of the remote actuator is a fixed end and the other end is a free end to facilitate deformation.

[0054] S212: A thermal field with the same temperature as the austenite surface temperature in the memory alloy coil was loaded on the finite element model to incorporate temperature-displacement coupling.

[0055] Specifically, a corresponding temperature field is set in the finite element model, and a thermal field with the same temperature as the surface temperature of austenite in the memory alloy coil is loaded in the finite element model to achieve accurate simulation conditions and facilitate subsequent accurate first simulation results.

[0056] S22: driving the elastic polyethylene substrate to deform, recording the tip displacement of the distal actuator and the deformation of the polyethylene substrate, and establishing a first relationship between the tip displacement and the curvature of the distal actuator.

[0057] Specifically, the polyethylene substrate is driven to deform, and the tip displacement of the distal actuator and the deformation amount of the polyethylene substrate are recorded, thereby establishing a first relationship between the tip displacement and the curvature of the distal actuator.

[0058] Please continue reading Figure 2 In step S20, the step of simulating the deformation of the remote actuator using a finite element model to obtain a first simulation result includes:

[0059] S23: simulating the tip displacement of the distal actuator using a finite element model, and determining the curvature of the distal actuator according to a pre-established first relationship.

[0060] Specifically, a first relationship between the tip displacement and the curvature of the distal effector is established in advance, and subsequently the curvature of the distal effector is determined through the tip displacement information of the distal effector in the finite element model.

[0061] See also Figure 3 In one embodiment, step S23 includes:

[0062] The curvature of the remote actuator is obtained according to the following formula:

[0063]

[0064] Among them, the deformation parameter is R S , the tip length of the distal actuator is L, Δx is the length of the positive projection of the tip position after deformation on the side away from the fixed end, and Δy is the difference between the tip length L of the distal actuator and the displacement of the tip of the distal actuator on the Y axis after deformation.

[0065] In one embodiment, continue to refer to Figure 3 After the tip of the distal actuator is deformed, a circle is drawn with the deformed tip as an arc, the length is L, the displacement of the tip on the X axis is Δx, the displacement on the Y axis is Δy, and the deformation parameter is R S According to the Pythagorean theorem, we can get:

[0066] (R s -Δx) 2 +(L-Δy) 2 =R s 2

[0067] The calculation formula of curvature K is obtained by deforming the above formula.

[0068] See also Figure 4 In one embodiment, step S30 includes:

[0069] S31: Compare a first curvature corresponding to a first theoretical result and a second curvature corresponding to a first simulation result to obtain a difference between the first curvature and the second curvature.

[0070] Specifically, the first curvature is determined by a first theoretical result, the second curvature is determined by a first simulation result, the first curvature and the second curvature are compared to obtain a difference between the first curvature and the second curvature.

[0071] S32: Determine the degree of agreement between the first theoretical result and the first simulation result according to the difference between the first curvature and the second curvature, wherein the degree of agreement is inversely proportional to the difference.

[0072] Specifically, the degree of fit between the first theoretical result and the first simulation result is determined by the difference between the first curvature and the second curvature, wherein the larger the difference, the lower the degree of fit; the smaller the difference, the higher the degree of fit, and at this time the degree of fit is inversely proportional to the difference.

[0073] See also Figure 5 and Figure 6 In one embodiment, the preparation method further comprises:

[0074] S251: Change the residual strain of the memory alloy coil, and the residual strain is selected in the range of 0-5%.

[0075] Specifically, the residual strain of the memory alloy coil in the finite element model was increased from 0 to 5%, and the mathematical model and the finite element model were verified.

[0076] S252: Obtain the first theoretical results of the remote actuator from the mathematical model.

[0077] The first theoretical results were obtained in the mathematical model for residual strains ranging from 0 to 5%.

[0078] S253: Obtain a first simulation result of the remote actuator from the finite element model.

[0079] The first simulation results corresponding to residual strains of 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, and 0.5 were obtained through the finite element model.

[0080] Continue reading Figure 6 , comparing the first theoretical result and the first simulation result, when the residual strain of the memory alloy coil increases from 0 to 5%, the curvature of the remote actuator also increases. The simulation results given by the finite element model are very consistent with the theoretical solution. The error between the theoretical and simulation results can be partially explained by the mesh and ideal constraint settings in the finite element modeling.

[0081] Specifically, residual strain refers to the strain retained by the memory alloy coil (SMA) after undergoing a specific processing process. Specifically, residual strain is generated when the SMA undergoes a detwinning process, which is usually completed by applying a certain tensile stress. The detwinning process causes the SMA to transform from the twinned martensite phase to the austenite phase, and a certain amount of residual strain is generated in the process. These residual strains will be released during the subsequent heating process, thereby driving the deformation of the distal actuator of the microcatheter.

[0082] In the experiment of this application, after the SMA wire was subjected to tensile stress treatment at room temperature, it was partially transformed into a twinned martensite phase in a detwinned state, and retained about 5% residual strain. When the SMA wire was heated above the austenite finish temperature, these residual strains were released, causing the SMA wire to shrink significantly, thereby driving the microcatheter distal actuator embedded in the polyethylene (PE) substrate to deform efficiently.

[0083] See also Figure 7 and Figure 8 , the preparation method further comprises:

[0084] S254: Using the same radius polyethylene substrate, change the offset position of the memory alloy coil.

[0085] In one embodiment, the offset position of the memory alloy coil also significantly affects the curvature of the remote actuator. A polyethylene substrate with a constant radius of 0.5 mm is used, and the memory alloy coil is embedded in the polyethylene substrate. The expected curvature of the remote actuator with respect to the offset position of the memory alloy coil is studied.

[0086] S255: Obtain the first theoretical results of the remote actuator from the mathematical model.

[0087] The first theoretical results were obtained in the mathematical model for offset positions ranging from 0 to 0.4 mm.

[0088] S256: Obtain a first simulation result of the remote actuator from the finite element model.

[0089] The first simulation results corresponding to the offset positions of 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, and 0.4 mm were obtained through the finite element model.

[0090] Continue reading Figure 8, the theoretical results given by the analytical model show that the curvature initially increases and then gradually decreases as the distance between the memory alloy coil and the center of the polyethylene substrate increases. This trend is consistent with the simulation results obtained by the finite element model, and also proves the reliability of the proposed mathematical model in predicting the bending of the remote actuator. Obviously, the maximum curvature occurs when the memory alloy coil with a diameter of 0.3mm is embedded in the polyethylene substrate with a diameter of 0.5mm. In addition, it is also worth noting that the error between the theoretical and simulation results grows with the offset position of the memory alloy coil.

[0091] See also Fig. 9 and Fig.10 , the preparation method further comprises:

[0092] S257: Use the same diameter memory alloy coil and change the radius of the polyethylene base.

[0093] In addition to the residual strain and the bias position of the memory alloy coil, it is also crucial to determine the optimal radius of the polyethylene substrate in narrow and complex blood vessels. A memory alloy coil with a diameter of 0.3 mm was selected to be embedded in the polyethylene substrate, and the effect of the polyethylene substrate diameter on the curvature of the distal actuator was confirmed.

[0094] S258: Obtaining the first theoretical results of the remote actuator from the mathematical model.

[0095] The first theoretical results were obtained in the mathematical model for polyethylene substrates with radii of 0.4-0.6 mm, respectively.

[0096] S259: Obtain a first simulation result of the remote actuator from the finite element model.

[0097] The first simulation results corresponding to the polyethylene substrate radius of 0.4, 0.45, 0.5, 0.55, and 0.6 mm were obtained through the finite element model.

[0098] Continue reading Fig.10 , it can be concluded that as the diameter of the polyethylene substrate increases, the curvature of the distal actuator decreases. The high consistency between the theoretical and simulation results also verifies the accuracy of the mathematical model in quickly predicting and optimizing the distal actuator of the microcatheter.

[0099] See also Fig.11 The method for preparing the microcatheter further comprises:

[0100] S100: preparing a remote actuator: selecting a memory alloy coil with a first diameter and a polyethylene substrate with a second inner diameter.

[0101] Firstly, a first diameter of the memory alloy coil and a second inner diameter of the polyethylene substrate are determined.

[0102] S200: performing a twist removal process on the memory alloy coil.

[0103] The twist removal process can retain a certain residual strain in the memory alloy coil under appropriate tensile force.

[0104] S300: The memory alloy coil is placed in a steel mold with an offset.

[0105] A certain offset position can ensure that the curvature change of the remote actuator meets the requirements.

[0106] S400: Liquid polyethylene is injected into the mold and solidified.

[0107] In one embodiment, a steel mold may be used and the liquid polyethylene may be cured to a solid state.

[0108] S500: taking the solidified polyethylene substrate and the memory alloy coil out of the mold.

[0109] After curing, the polyethylene substrate and the memory alloy coil are removed from the mold, and the remote actuator is now ready.

[0110] S600: The distal actuator and the polyethylene catheter are combined to obtain a microcatheter.

[0111] Specifically, a polyethylene catheter and a distal actuator are combined to obtain a microcatheter.

[0112] The above description is only an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for preparing a microcatheter, characterized in that: The preparation method comprises: A mathematical model is used to predict the deformation of a distal actuator in a microcatheter, and a first theoretical result is obtained, wherein the distal actuator includes a polyethylene substrate and a memory alloy coil; Using the finite element method to establish a finite element model, and using the finite element model to simulate the deformation of the remote actuator to obtain a first simulation result; Comparing the first theoretical result with the first simulation result to obtain a degree of agreement between the first theoretical result and the first simulation result; In response to the degree of fit meeting a preset requirement, microcatheters are batch-produced according to the parameters of the microcatheters.

2. The preparation method according to claim 1, characterized in that: The step of using a mathematical model to predict the deformation of the distal actuator in the microcatheter to obtain a first theoretical result comprises: The negative thermal strain of the memory alloy coil is determined according to the following formula: Wherein, εo represents the negative thermal strain of the memory alloy coil, represents the maximum residual strain of the memory alloy coil after detwinning; The first theoretical result of the remote actuator is determined according to the negative thermal strain of the memory alloy coil.

3. The preparation method according to claim 1, characterized in that: The step of establishing a finite element model using the finite element method comprises: Simplifying the remote actuator into a polyethylene substrate embedded with two memory alloy coils; driving the elastic polyethylene substrate to deform, recording the tip displacement of the distal actuator and the deformation of the polyethylene substrate, and establishing a first relationship between the tip displacement and curvature of the distal actuator; The step of simulating the deformation of the remote actuator using the finite element model to obtain a first simulation result includes: The finite element model is used to simulate the tip displacement of the distal effector, and the curvature of the distal effector is determined according to the pre-established first relationship.

4. The preparation method according to claim 3, characterized in that: The step of establishing a finite element model using the finite element method also includes: The constraint between the polyethylene substrate and the memory alloy coil in the finite element model is set as a binding constraint; the boundary condition is that one end is a fixed end and the other end is a free end; A thermal field having the same temperature as the surface temperature of the austenite in the memory alloy coil is loaded on the finite element model to incorporate temperature-displacement coupling.

5. The preparation method according to claim 4, characterized in that: The step of comparing the first theoretical result with the first simulation result to obtain the degree of agreement between the first theoretical result and the first simulation result includes: Comparing a first curvature corresponding to the first theoretical result and a second curvature corresponding to the first simulation result to obtain a difference between the first curvature and the second curvature; The degree of agreement between the first theoretical result and the first simulation result is determined according to the difference between the first curvature and the second curvature, wherein the degree of agreement is inversely proportional to the difference.

6. The preparation method according to claim 3, characterized in that: The step of simulating the tip displacement of the distal actuator by using the finite element model and determining the curvature of the distal actuator according to the first relationship established in advance comprises: The curvature of the remote actuator is obtained according to the following formula: Among them, the deformation parameter is R S , the tip length of the distal actuator is L, Δx is the length of the orthographic projection of the tip position on the side away from the fixed end, and Δy is the difference between the tip length L of the distal actuator and the displacement of the distal actuator tip on the Y axis after deformation.

7. The preparation method according to claim 6, characterized in that: The preparation method further comprises: Changing the residual strain of the memory alloy coil, wherein the residual strain is selected within a range of 0-5%; Obtaining a first theoretical result of the remote effector from the mathematical model; A first simulation result of the remote effector is obtained from the finite element model.

8. The preparation method according to claim 6, characterized in that: The preparation method further comprises: Using the polyethylene substrate with the same radius, changing the bias position of the memory alloy coil; Obtaining a first theoretical result of the remote effector from the mathematical model; A first simulation result of the remote effector is obtained from the finite element model.

9. The preparation method according to claim 6, characterized in that: The preparation method further comprises: Using the memory alloy coil with the same diameter, changing the radius of the polyethylene substrate; Obtaining a first theoretical result of the remote effector from the mathematical model; A first simulation result of the remote effector is obtained from the finite element model.

10. The method according to claim 1, characterized in that The method further comprises: Prepare the remote actuator: select the memory alloy coil with a first diameter and the polyethylene substrate with a second inner diameter; performing a twist removal process on the memory alloy coil; placing the memory alloy coil in a steel mold in an offset manner; Liquid polyethylene is injected into the mold and allowed to solidify; removing the solidified polyethylene substrate and the memory alloy coil from the mold; The distal end actuator and the polyethylene catheter are combined to obtain a microcatheter.

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