Medical guidewire control method and control system

Abstract

The present invention provides a medical guidewire control method and control system, which relates to the technical field of vascular intervention surgery. The medical guidewire control method includes: obtaining the actual position and actual direction of the current position of the guidewire, and determining the expected position of the next position of the guidewire; changing the speed of the guidewire and obtaining the expected direction of the next position of the guidewire according to the difference between the actual position of the current position of the guidewire and the expected position of the next position; changing the direction of the guidewire according to the difference between the actual direction of the current position of the guidewire and the expected direction of the next position. The present invention discloses a dual-loop control strategy using an exponential sliding mode control method, so that the guidewire can autonomously turn and reach a specified position.

Description

Technical Field

[0001] The present invention relates to the technical field of vascular intervention surgery, and in particular to a medical guide wire control method and control system. Background Art

[0002] Cardiovascular and cerebrovascular diseases have high morbidity and mortality rates, which seriously threaten human health. Currently, vascular intervention surgery is widely used as an important means of cardiovascular and cerebrovascular treatment. In traditional vascular intervention surgery, doctors manually insert catheters, guide wires, stents and other instruments into the patient's body. On the one hand, during the operation, as the doctor's physical strength decreases, his attention and stability decrease, resulting in reduced operation accuracy and prone to accidents; on the other hand, long-term exposure of doctors to radiation will greatly increase their chances of suffering from leukemia, cancer and acute cataracts, which seriously threatens the health of doctors.

[0003] Emerging surgical methods using robotic catheters and guidewires can effectively address the above problems, but current interventional surgical robots are mostly open-loop controlled, with low precision and prone to overshoot, which affects the success rate of the surgery. In addition, the robot's guidewire has a strong nonlinear characteristic when turning in a magnetic field, so its steering task is mostly completed by doctors remotely. Medical guidewires cannot be fully autonomously controlled, resulting in low efficiency of vascular interventional surgery using medical guidewires. Summary of the invention

[0004] In view of the above technical problems, the present invention provides a medical guidewire control method and control system, and discloses a dual-loop control strategy using an exponential sliding mode control method, so that the guidewire can autonomously turn and reach a specified position. The technical solution is as follows:

[0005] The present invention specifically provides a medical guidewire control method, which includes: obtaining the actual position and actual direction of the guidewire's current position, and determining the expected position of the guidewire's next position; changing the speed of the guidewire and obtaining the expected direction of the guidewire's next position based on the difference between the actual position of the guidewire's current position and the expected position of the next position; and changing the direction of the guidewire based on the difference between the actual direction of the guidewire's current position and the expected direction of the next position.

[0006] Furthermore, the method of changing the speed of the guidewire and obtaining the desired direction of the next position of the guidewire according to the difference between the actual position of the current position of the guidewire and the desired position of the next position specifically includes: designing a first sliding surface according to the difference between the actual position of the current position of the guidewire and the desired position of the next position, introducing a first exponential function into the first sliding surface, calculating a first control law according to the first sliding surface, and using the first control law to change the speed of the guidewire and obtain the desired direction of the next position of the guidewire.

[0007] Furthermore, the method of changing the direction of the guidewire according to the difference between the actual direction of the current position of the guidewire and the expected direction of the next position specifically includes: designing a second sliding surface according to the difference between the actual direction of the current position of the guidewire and the expected direction of the next position, introducing a second exponential function into the second sliding surface, calculating a second control law according to the second sliding surface, and changing the direction of the guidewire using the second control law.

[0008] Further, the obtaining of the actual position and actual direction of the current position of the guidewire is specifically: imaging the head of the guidewire, and obtaining the position and direction of the guidewire head according to the imaging information.

[0009] Further, the determining of the expected position of the next position of the guidewire is specifically: determining the expected running trajectory of the guidewire, and determining the expected position of the next position according to the actual position of the current position of the guidewire.

[0010] The present invention also specifically provides a medical guidewire control system, comprising a magnetic structure fixed to the guidewire head and a driving device connected to the guidewire; further comprising: a direction adjustment module, which comprises a magnet and a displacement component connected to the magnet; an imaging module, the expected motion trajectory of the guidewire is within the imaging range of the imaging module, and is used to identify the position information of the magnetic structure; a control module, which respectively connects the imaging module, the driving device and the displacement component by signals, and controls the driving device and the displacement component according to the position information to drive the guidewire to move to a predetermined position of the expected motion trajectory.

[0011] Furthermore, the color of the head of the guide wire is different from the color of other parts of the guide wire.

[0012] Furthermore, the magnet is a permanent magnet, and the magnetic material is a permanent magnet.

[0013] Furthermore, the displacement assembly includes a mechanical arm, and the permanent magnet is arranged at the execution end of the mechanical arm.

[0014] Beneficial effects of the present invention:

[0015] The dual-loop sliding mode control method and the constructed steering control system proposed in the present invention can complete the autonomous control of the medical guidewire without any artificial remote assistance, and can perform precise path following and direction control without overshoot, which can effectively protect blood vessels and effectively improve the efficiency of vascular interventional treatment operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for describing the embodiments of the present invention are briefly introduced below.

[0017] Figure 1 It is a structural schematic diagram of a medical guidewire control system;

[0018] Figure 2 is a schematic diagram of an approximate physical model of a curved guidewire;

[0019] Figure 3 It is a schematic diagram of a medical guide wire control method flow chart;

[0020] Figure 4 It is a flow chart of a medical guidewire control method.

[0021] Throughout the several views, the same reference numerals designate identical or similar parts or components.

[0022] 1. Imaging module; 2. Magnet; 3. Displacement component; 4. Blood vessel model; 5. Guide wire; 6. Driving device. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar components or components with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0024] In the description of this specification, if the terms "embodiment one", "this embodiment", "in an embodiment" and the like appear, it means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example; moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in an appropriate manner.

[0025] In the description of this specification, the terms "connect", "install", "fix", "set", "have", etc. are all understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0026] In the description of this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0027] In one embodiment, Figure 1 As shown, a control system for a medical guidewire 5 includes a magnetic structure fixed to the head of the guidewire 5 and a driving device 6 connected to the guidewire 5. The control system for the medical guidewire 5 also includes a direction adjustment module, an imaging module 1 and a control module. The direction adjustment module includes a magnet 2 and a displacement component 3 connected to the magnet 2. The expected motion trajectory of the guidewire 5 is within the imaging range of the imaging module 1, and the imaging module 1 is used to identify the position information of the magnetic structure. The control module is connected to the imaging module 1, the driving device 6 and the displacement component 3 by signals, and controls the driving device 6 and the displacement component 3 according to the position information to drive the guidewire 5 to move to a predetermined position of the expected motion trajectory. Among them, the control module can be set as a computer running the Linux system, the imaging module 1 can be a Blackfly S BFS-U3-50S5C camera, and the driving device 6 can be a DC motor.

[0028] The guide wire 5 is an almost inelastic rigid wire, so the speed received by the guide wire 5 can be directly converted to the head of the guide wire 5, that is, the speed of the head of the guide wire 5 is equal to the speed output by the drive device 6, so the speed of the head of the guide wire 5 can be changed by simply changing the speed output by the drive device 6. The magnetic material at the head of the guide wire 5 is within the magnetic field formed by the magnet 2, so the magnet 2 can control the direction of the head of the guide wire 5 through the magnetic force between the magnet 2 and the magnetic material, and the direction of the head of the guide wire 5 can be further adjusted by adjusting the position of the magnet 2 by the displacement component 3. The imaging module 1 can image the head of the guide wire 5, and the control module calculates the position and posture of the head of the guide wire 5 according to the imaging, and then the control module controls the drive device 6 and the direction adjustment module according to the expected path of the guide wire 5 and the actual position and posture of the guide wire 5, and finally the guide wire 5 can be driven to the specified position in the vascular model 4, realizing the autonomous control of the medical guide wire 5 and improving the efficiency of the vascular intervention surgery with the help of the medical guide wire 5.

[0029] In one embodiment, the color of the head of the guide wire 5 is different from the color of other parts of the guide wire 5 , so that the imaging module 1 can image the head of the guide wire 5 more clearly, which is convenient for subsequent calculations.

[0030] In one embodiment, the magnet 2 is a permanent magnet, the magnetic material is the permanent magnet 2, the permanent magnet and the permanent magnet 2 have stable magnetism, and the magnetic force is more reliable. The size of the permanent magnet can be 75×55×30 mm 3 .

[0031] In one embodiment, the displacement assembly 3 includes a mechanical arm, and the permanent magnet is arranged at the execution end of the mechanical arm. The mechanical arm has multiple degrees of freedom and can control the permanent magnet 2 to move freely in three-dimensional space. Specifically, the mechanical arm can be a UR mechanical arm.

[0032] In one embodiment, a medical guidewire control method includes: obtaining the actual position and actual direction of the guidewire's current position, and determining the expected position of the guidewire's next position; changing the speed of the guidewire and obtaining the expected direction of the guidewire's next position based on the difference between the actual position of the guidewire's current position and the expected position of the next position; and changing the direction of the guidewire based on the difference between the actual direction of the guidewire's current position and the expected direction of the next position.

[0033] The medical guidewire control method of this embodiment eliminates the position error by changing the speed of the guidewire and obtains the desired direction of the next position at the same time. The direction error is obtained by the actual position of the current position and the desired direction of the next position obtained in the previous step, and the direction error is eliminated by changing the direction of the guidewire, that is, the output of the previous step is the input of the next step. Therefore, there is no need for the doctor to manually control the guidewire steering. The dual-loop control method can make the guidewire move autonomously according to the expected trajectory, with high accuracy and less prone to overshoot, which greatly improves the success rate and efficiency of vascular intervention surgery using medical guidewires.

[0034] In one embodiment, according to the difference between the actual position of the current position of the guide wire and the expected position of the next position, the speed of the guide wire is changed, and the expected direction of the next position of the guide wire is obtained, which specifically includes:

[0035] A first sliding surface is designed according to the difference between the actual position of the current position of the guidewire and the expected position of the next position, and a first exponential function is introduced into the first sliding surface. A first control law is calculated according to the first sliding surface, and the speed of the guidewire is changed by using the first control law to obtain the expected direction of the next position of the guidewire.

[0036] First, define the various parameters, and then establish the mathematical model of the medical guidewire:

[0037] The desired position, velocity, and acceleration of the guidewire 5 in the blood vessel model 4 are: The actual position, velocity and acceleration of the guide wire 5 in the blood vessel model 4 are: The desired azimuth and elevation angles of the guidewire 5 in the blood vessel model 4: ψ r (t) = [θ r (t) φ r (t)] T . Where T represents the transpose of the vector; t represents the time. For the convenience of description, (t) is omitted in the subsequent formulas.

[0038] The first point of the guide wire 5 head is selected as the observation point, and the actual speed and position can be measured. Therefore, the position error between the expected path and the actual path is: e = x r -x. By changing the velocity vector To eliminate the position error, the speed output by the drive device 6 is defined as v, and the speed v output by the drive device 6 is controllable. The deflection speed is controlled by the robot arm, and the behavior of the permanent magnet clamped at the end of the robot arm is defined as: g(ψ r ), control command: τ=vg(ψ r ). Among them, g(ψ r ) contains the required unit vector of the direction information. The control actuator is a permanent magnet and a drive device 6 mounted on the end effector of the robot arm, which are responsible for g(ψ) and v respectively. The drive device 6 provides the required velocity v of the guide wire 5.

[0039] The direction vector is function, so: The position tracking system is a first-order dynamic system, and the state equation is: The goal is to calculate the appropriate v and ψ r , control the conveyor and the end effector of the robot arm so that the tip trajectory of the guide wire 5 is ψ r , then ψ=ψ, where x end represents the position of a permanent magnet or the end effector of a robot arm, is the angular velocity of the guide wire 5 head. f(.) is a known nonlinear mapping function determined by the properties of the permanent magnet 2 and the material of the guide wire 5 head. end -x represents the relative position of the guide wire 5 head and the permanent magnet at the end of the robotic arm, and the formula A relationship between the relative position and the angular velocity of the guide wire 5 head is established.

[0040] The direction of the magnetic field will affect the orientation of the head of the guide wire 5. The permanent magnet will push the head of the guide wire 5 in the same direction as the magnetic field formed by the permanent magnet. Therefore, the current direction of the guide wire 5 represented by g(ψ) will also affect the angular velocity. The calculation formula of the magnetic field is: Where r = xx endB is the magnetic field, μ0 is the magnetic permeability of free space, I is the 3×3 unit matrix, and m is the magnetic moment of the permanent magnet, which is determined by the material of the permanent magnet mounted on the end effector of the robot arm. In addition, the posture of the permanent magnet to the guide wire 5 will also affect m. The material of the permanent magnet is known, and the posture of the permanent magnet to the guide wire 5 can also be determined, so m is a known 3×1 constant vector.

[0041] The torque of the permanent magnet on the end effector of the robot arm on the permanent magnet 2 at the head of the guide wire 5 is: Where V is the known norm of the magnetic moment of the permanent magnet 2 at the head of the guide wire 5. Therefore, Vg(ψ) is the magnetic moment of the permanent magnet 2 at the head of the guide wire 5 (determined by the material and posture of the permanent magnet 2 at the head of the guide wire 5). T is a 3×1 vector, and × is the bifurcation product.

[0042] The guide wire 5 is made of a special material and has the characteristics of a soft rigid body. The rotation of the guide wire 5 itself is not considered here. like Figure 2 As shown, the physical model of the guide wire 5 can be defined as: Among them, ε is a 3×1 vector, including small movements in three directions: direction angle, pitch angle, and self-rotation. is an intermediate variable, which is limited to zero by the driving device 6. E is a given constant determined by the shape of the magnetic guide wire 5 head, and S is the stiffness parameter of the guide wire 5 head.

[0043] Finally, we can perform an integral operation to get the angle expression, which is: Where l is the length of the guide wire 5 delivered, and ζ is a constant vector. Calculating the derivative with respect to time t, we obtain:

[0044] In practical applications, Very small, because the guide wire 5 moves slowly during the steering task, so The term is ignored and the corresponding negative impact is regarded as system uncertainty, which can be eliminated by appropriate control strategies. That is, the transmission speed. Therefore, the above formula: This is the calculation formula for the angular velocity of the guide wire 5 head, where r = xx end This formula establishes the relationship between the relative position of the permanent magnet 2 at the head of the guide wire 5 and the permanent magnet at the end of the robot arm and the angular velocity of the head of the guide wire 5.

[0045] Next, an outer loop controller is set to control the position of the medical guide wire to reduce the position error e = x r -x, makes the position error converge to 0, specifically:

[0046] Step 1: Design a first sliding surface based on the difference e between the actual position of the current guide wire and the expected position of the next position, and introduce the first exponential function to the first sliding surface. Use the integral term on the first sliding surface to ensure that the position error approaches 0. Add the integral term to eliminate the steady-state error, and the system will eventually be within the sliding surface. The sliding surface function is: s out =c1e+c2∫edt. Where c1 and c2 are positive parameters adjusted by the user, the parameters should satisfy the Hurwitz condition (a necessary and sufficient condition for determining whether all roots of a real coefficient polynomial have a negative real part), and c2 = 1, where out indicates that the variable belongs to the outer loop controller.

[0047] Step 2: Calculate the first control law based on the first sliding surface. Since the speed is controllable, the derivative of the position error is not added to the designed first sliding surface, and the derivative of the sliding surface function is: Applying the exponential reaching law, we get: Among them, α and β are adjustable parameters, and exponential approximation is used in the sliding surface reaching law to achieve fast convergence performance.

[0048] b is the positive boundary parameter used by the saturation function sat(n), indicating n is a parameter. In the above formula, the parameter n is s out If the input n becomes a vector, the result of sat(n) will be a vector, and all input vector elements will be evaluated one by one. b is always set to a small value. Using sat(s out )The motivation is to suppress the jitter problem of the SMC method.

[0049] Step 3: Use the first control law to change the speed of the guidewire and obtain the desired direction of the next position of the guidewire. Use the above formula to solve the equations and eliminate What we get: Substitute e = x r -x, move to get (Here is the position derivative to get the speed):

[0050] The Lyaponuv function is defined as: Taking the derivative of it, we get: Will Substitute the formula: In order to satisfy the Lyaponuv function, It is required that: α>0, β>0 are satisfied at the same time. Stable controller parameter constraints can be obtained using Lyapunov theory.

[0051] By calculating the Euclidean norm (‖·‖) and the normalized direction vector, v and g (ψ r ). In summary, the outer loop control strategy is:

[0052]

[0053] You can adjust the parameters c1 and c2 to make s out =0 is on the sliding surface, which means stable convergence.

[0054] This is the formula for the aforementioned modeling, which is used to calculate the velocity v and attitude (direction angle, elevation angle). The velocity v will be output by the drive device 6. At the same time, the desired direction command Will be sent to the inner loop controller described below.

[0055] This embodiment reduces the position error through outer loop control and determines the speed v that the drive device 6 needs to output. In order to solve the uncertainty and nonlinearity in the design system, the sliding mode control (SMC) method is applied, and the exponential approximation is used in the sliding surface approach law to achieve fast convergence performance. In addition, the Lyapunov theory is also used to derive the convergence parameter constraints, which ultimately enables the medical guide wire to move smoothly and reach the specified position autonomously.

[0056] In one embodiment, the direction of the guidewire is changed according to the difference between the actual direction of the current position of the guidewire and the expected direction of the next position, specifically including: designing a second sliding surface according to the difference between the actual direction of the current position of the guidewire and the expected direction of the next position, introducing a second exponential function to the second sliding surface, calculating a second control law according to the second sliding surface, and using the second control law to change the direction of the guidewire.

[0057] The permanent magnet installed on the robot arm is used to adjust the movement direction of the guide wire 5. In fact, there are two guiding modes for the guide wire 5, mode 1 is trajectory following, and mode 2 is trajectory tracking. Specifically, in mode 1, there is no speed requirement for the guiding task of the guide wire 5, and the user can set a suitable constant speed and only focus on the direction control of the guide wire 5. In mode 2, there is a speed requirement for the guiding task of the guide wire 5, requiring the guide wire 5 to accurately track the predetermined speed at different positions in the reference trajectory. Mode 1 is a special case of mode 2, and we mainly solve the guiding method of mode 2.

[0058] Set up an inner loop controller to control the direction of the medical guidewire and reduce the direction error e a =ψ r -ψ, so that the direction error converges to 0, specifically:

[0059] Step 1: Similarly, the second sliding surface is designed according to the difference between the actual direction of the current position of the guidewire and the desired direction of the next position obtained by the outer loop controller, and a second exponential function is introduced into the second sliding surface. An integral sliding mode control algorithm with an exponential approximation law is developed in the direction of the guidewire 5. The corresponding sliding mode is designed as: s in =k1e a +k2∫e a dt. The superscript in indicates the inner loop controller, k1 and k2 are SMC parameters and are positive values.

[0060] Step 2: Calculate the second control law based on the second sliding surface. To calculate the angular velocity, take the derivative of the above equation and get the equation for the angular velocity: Using the exponential reaching law to approximate this formula we get:

[0061] Step 3: Use the second control law to change the direction of the guidewire. in The derivative of , combined with the reaching law, is: Among them, some new parameters are used to help indicate the difference between the inner loop and outer loop controllers. The above formulas are solved together to derive the control strategy, and the controllable angular velocity of the head of the guide wire 5 is expressed as: Move to get: Among them, η>0γ>0, which need to be satisfied at the same time. You can adjust the parameters k1 and k2 to make s in = 0 is on the sliding surface, which is also stable convergence. At the same time, the uncertainty of the system model, external interference and model parameter disturbance can be overcome by selecting larger η, γ or α, β.

[0062] Using the above obtained This nonlinear function, the inverse function is x end , and bring in The calculation formula for the position of the permanent magnet at the end of the robot arm is: According to this formula, the robot arm end effector will be manipulated to change the angular velocity of the current guide wire 5 head Finally achieve the expected direction ψ r .

[0063] This embodiment reduces the directional error through inner loop control. In order to solve the uncertainty and nonlinearity in the design system, the sliding mode control (SMC) method is applied, and the exponential approximation is used in the sliding surface approach law to achieve fast convergence performance. The sliding mode control (SMC) method has the advantages of simple structure, strong robustness to various disturbances, nonlinear parameter perturbations and modeling uncertainties. In addition, Lyapunov theory is also used to derive the convergence parameter constraints. Moreover, the dual-loop magnetic control strategy using the exponential sliding mode control method can converge quickly without overshoot problems, which can significantly avoid blood vessel damage, and finally achieve the purpose of smooth movement of the medical guide wire and autonomously reaching the designated position.

[0064] In one embodiment, the actual position and actual direction of the current position of the guidewire are obtained by imaging the head of the guidewire and calculating the actual position and actual direction of the guidewire head based on the imaging information. The tip of the guidewire is selected as the position measurement point, and the position and direction information are obtained by visual measurement, and then the position error e and direction error e are calculated. a In this embodiment, the coordinates, direction angle and elevation angle of a three-dimensional point in space are calculated by two cameras to obtain x and ψ. The path of the guide wire is known, so the desired position x r It is known that the outer loop controller calculates the desired direction ψ of the guidewire r ; Make a difference to get the position error: e = x r -x and direction errors: e a =ψ r In other embodiments, the actual position and actual direction of the guidewire head may also be obtained by other visual measuring instruments.

[0065] In one embodiment, the expected position of the next position of the guidewire is determined by: determining the expected trajectory of the guidewire, and determining the expected position of the next position based on the actual position of the current position of the guidewire using medical imaging, mathematical models, computer simulation and other technologies.

[0066] like Figure 3 , 4 As shown, the controller input is the position error e and the reference speed x r , the controller output (controllable parameter) is the position x of the robot arm end effector endand the transmission speed v. The control system contains two loops, so two series controllers are required. The output of the outer loop controller will be the input of the inner loop controller, which realizes the smooth movement of the magnetic guidewire 5 and can reach the designated position autonomously, without the need for the doctor to perform the steering task of the slot guidewire 5, thereby improving the efficiency of vascular intervention surgery with the aid of the medical guidewire 5. Therefore, the dual-loop sliding mode control method and the constructed steering system proposed in the present invention can complete autonomous control without any manual remote assistance, and can perform precise path following and direction control without overshoot, which can effectively protect blood vessels and effectively improve the efficiency of vascular intervention surgery.

[0067] The above description of the embodiments is to facilitate ordinary technicians in the technical field to understand and apply the technology of this case. People familiar with the technology in this field can obviously easily make various modifications to these examples and apply the general principles described here to other embodiments without creative work. Therefore, this case is not limited to the above embodiments. Modifications to the following situations should all be within the scope of protection of this case: ① A new technical solution implemented based on the technical solution of the present invention and combined with existing common knowledge, the technical effect produced by the new technical solution does not exceed the technical effect of the present invention; ② The equivalent replacement of some features of the technical solution of the present invention by using known technology, the technical effect produced is the same as the technical effect of the present invention; ③ The technical solution of the present invention can be expanded, and the substantive content of the expanded technical solution does not exceed the technical solution of the present invention; ④ The equivalent transformation made by using the contents of the description and drawings of the present invention is directly or indirectly applied to other related technical fields.

Claims

1. A medical guidewire control system, based on a guidewire control method, characterized in that: It includes a magnetic structure fixed to the guide wire head and a driving device connected to the guide wire driving device; and also includes: A direction adjustment module, comprising a magnet and a displacement assembly drivingly connected to the magnet; An imaging module, the expected motion trajectory of the guidewire is within the imaging range of the imaging module, and is used to identify the position information of the magnetic structure; a control module, which is respectively connected to the imaging module, the driving device and the displacement component by signals, and controls the driving device and the displacement component according to the position information to drive the guide wire to move to a predetermined position of the expected motion trajectory; The guidewire control method comprises: Obtaining the actual position and actual direction of the current position of the guidewire, and obtaining the expected position of the next position of the guidewire; According to the difference between the actual position of the current position of the guide wire and the expected position of the next position, the speed of the guide wire is changed, and the expected direction of the next position of the guide wire is obtained; Changing the direction of the guidewire according to the difference between the actual direction of the guidewire at the current position and the desired direction of the next position; The step of changing the speed of the guidewire according to the difference between the actual position of the current position of the guidewire and the expected position of the next position, and obtaining the expected direction of the next position of the guidewire specifically includes: Where v is the speed of the guide wire, g(ψ r ) is the desired direction of the next guidewire position, α and β are adjustable parameters, S out is the sliding surface function, b is the boundary positive parameter used by the saturation function sat(n), c1 and c2 are positive parameters adjusted by the user, e is the difference between the actual position of the guidewire at the current position and the expected position of the next position, is the desired speed of the guidewire; The changing the direction of the guide wire according to the difference between the actual direction of the current position of the guide wire and the expected direction of the next position specifically includes: changing the position of the permanent magnet at the end of the robot arm to change the direction of the guide wire; the position of the permanent magnet at the end of the robot arm is: Among them, x end is the position of the permanent magnet at the end of the robot arm, x is the actual position of the guide wire at the current position, η and γ are control gain parameters, η>0 and γ>0; s in is the sliding surface, the superscript in indicates the inner loop controller; b in is the scale factor of the saturation function; k1 and k2 are SMC parameters and are positive values; e a is the difference between the actual direction of the guidewire at the current position and the expected direction of the next position, is the desired angular velocity.

2. The medical guidewire control system according to claim 1, characterized in that: The obtaining of the actual position and actual direction of the current position of the guidewire is specifically: imaging the head of the guidewire, and obtaining the position and direction of the guidewire head according to the imaging information.

3. The medical guidewire control system according to claim 1, characterized in that: The obtaining of the expected position of the next position of the guidewire is specifically: obtaining the expected running trajectory of the guidewire, and obtaining the expected position of the next position according to the actual position of the current position of the guidewire.

4. The medical guidewire control system according to claim 1, characterized in that: The color of the head of the guide wire is different from the color of other parts of the guide wire.

5. The medical guidewire control system according to claim 4, characterized in that: The magnet is a permanent magnet, and the magnetic structure is a permanent magnet.

6. The medical guidewire control system according to claim 5, characterized in that: The displacement assembly comprises a mechanical arm, and the permanent magnet is arranged at the execution end of the mechanical arm.

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