Catheter bending steering control method, catheter system, and storage medium

Abstract

The application provides a catheter bending and steering control method, a catheter system and a readable storage medium. The method comprises the following steps: obtaining a position change amount of a catheter end according to a catheter steering instruction from a host controller, the position change amount comprising a direction angle and a bending angle; determining a driving wheel and a driven wheel in a plurality of driving wheels according to the position change amount, and calculating an angular position change amount of the driving wheel; calculating an angular position change amount of the driven wheel according to the angular position change amount of the driving wheel and a current position proportional distribution coefficient of the corresponding driven wheel; and controlling a driving motor to drive the corresponding driving wheel to rotate according to the angular position change amount. In the foregoing manner, the application can realize the bending and steering control of the catheter, simplify the calculation process of the angular position change amount, and shorten the response time of the catheter steering instruction.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of medical devices, and particularly relates to a catheter bending and steering control method, a catheter system, a control system thereof, and a computer readable storage medium. BACKGROUND

[0002] Minimally invasive medical techniques are intended to reduce the amount of tissue damaged during a medical procedure, to reduce patient recovery time, discomfort, and harmful side effects. In minimally invasive medical techniques, it is often necessary to insert a catheter to a target tissue location through a natural orifice in the patient's anatomy or through a surgical incision. In order for the catheter to reach the target tissue location, precise control of the steering of the catheter is required.

[0003] In the related art, precise control of the catheter is generally achieved by establishing a catheter kinematics model, i.e., finding a mapping relationship between the angle positions of the driving wheels that control the catheter and the pose of the catheter tip, and then substituting the target pose of the catheter into the kinematics model to solve the angle positions of the driving wheels. Since the catheter is a flexible continuum structure, in actual applications, the material properties, assembly process, temperature changes, external disturbances, and working space of the catheter greatly interfere with the kinematics description, resulting in a large deviation between the established kinematics model and the actual motion state, making it difficult to meet the demand for real-time precise control of the steering of the catheter. SUMMARY

[0004] The present application proposes a catheter bending and steering control method, a catheter system, a control system thereof, and a computer readable storage medium, which can solve the problem that the demand for real-time precise control of the steering of the catheter is difficult to meet in the related art.

[0005] The first aspect embodiment of the present application proposes a catheter system. The catheter system comprises a mechanical arm, a catheter instrument engaged with a power part of the mechanical arm, a master controller in communication connection with the mechanical arm, and a processor. The catheter instrument comprises an instrument box arranged to be engaged with the power part and a catheter connected with the instrument box, the instrument box comprises a driving wheel arranged to be driven by the power part and a driving wire having one end wound on the driving wheel and the other end extending along the catheter and fixed to a catheter tip. The power part comprises a plurality of driving motors, and the driving motors, the driving wheels and the driving wires are in one-to-one correspondence. The processor is configured to perform the following steps: obtaining a position change amount of the catheter tip according to a catheter steering instruction from the master controller, the position change amount comprising a direction angle and a bending angle; determining a driving wheel and a driven wheel in the driving wheels according to the position change amount and calculating an angle position change amount of the driving wheel; calculating an angle position change amount of the driven wheel according to the angle position change amount of the driving wheel and a current position proportional distribution coefficient of the corresponding driven wheel, the current position proportional distribution coefficient being used to represent the proportion of the take-up length of the driving wheel to the pay-off length of the corresponding driven wheel in the current state; and controlling the driving motor to drive the corresponding driving wheel to rotate according to the angle position change amount.

[0006] Wherein, the number of driving wires is n, n is an integer greater than 2, n driving wires divide the front end plane of the rotating section of the catheter into n intervals in angle, the two ends of the interval to which the direction angle belongs correspond to the driving wires of the active driving wire, the driving wheel connected to the active driving wire is the driving wheel, and part or all of the remaining driving wheels are driven wheels.

[0007] Wherein, the processor is configured to perform the following specific steps: calculating the position increment offset of the catheter end under the action of the position change amount; calculating the wire length of each driving wheel according to the position increment offset; and calculating the angular position change amount of the corresponding driving wheel according to the wire length of the driving wheel.

[0008] Wherein, the processor is configured to perform the following specific steps: obtaining the kinematic model of the rotating section; calculating the length difference of the active driving wire in the current state and in the target state under the action of the position change amount as the wire length of the driving wheel according to the kinematic model; and calculating the angular position change amount of the driving wheel according to the wire length of the driving wheel.

[0009] Wherein, the processor is configured to perform the following specific steps: calculating the single-wheel wire length according to at least the bending angle; calculating the wire length of each driving wheel according to the single-wheel wire length and the direction angle; and calculating the angular position change amount of the corresponding driving wheel according to the wire length of the driving wheel.

[0010] Wherein, the processor is configured to perform the following steps before performing the calculation of the angular position change amount of the driven wheel according to the angular position change amount of the driving wheel and the current position proportional distribution coefficient of the corresponding driven wheel: inputting the current bending angle of the catheter end into the pre-stored mapping relationship to obtain the current position proportional distribution coefficient of the driven wheel, and the input of the mapping relationship at least includes the current bending angle.

[0011] Wherein, the angular position change amount of the driven wheel is the sum of the product of the angular position change amount of the corresponding driving wheel of the driven wheel and the current position proportional distribution coefficient.

[0012] Wherein, the catheter steering instruction includes a first voltage and a second voltage collected on two mutually perpendicular axes of the master controller, the direction angle is calculated according to the ratio of the first voltage and the second voltage, the bending angle is calculated by integrating the bending speed with respect to the command holding time, and the bending speed is calculated according to the combined value of the first voltage and the second voltage.

[0013] The second aspect embodiment of the present application provides a steering control method for a catheter end. The method comprises: obtaining a position change amount of the catheter end according to a catheter steering instruction from a master controller, the position change amount comprising a direction angle and a bending angle; determining a driving wheel among a plurality of driving wheels as a driving wheel and a driven wheel according to the position change amount, and calculating an angle position change amount of the driving wheel, the driving wheel being arranged in one-to-one correspondence with a driving motor and a driving wire, the driving wire being wound on the driving wheel and driven by the corresponding driving motor, the other end of the driving wire extending along the catheter and being fixed to the catheter end; calculating an angle position change amount of the driven wheel according to the angle position change amount of the driving wheel and a current position proportional distribution coefficient of the corresponding driven wheel, the current position proportional distribution coefficient being used to represent a proportion of a take-up length of the driving wheel to a pay-off length of the corresponding driven wheel in the current state; and controlling the driving motor to drive the corresponding driving wheel to rotate according to the angle position change amount.

[0014] The third aspect embodiment of the present application provides a control system of a catheter system. The control system comprises: a memory for storing computer program instructions; and a processor for loading and executing the computer program instructions; wherein the computer program instructions are configured to be loaded and executed by the processor to implement the method of the second aspect of the present application.

[0015] The fourth aspect embodiment of the present application provides a computer readable storage medium having computer program instructions stored thereon, the computer program instructions being executed by a processor to implement the method of the second aspect of the present application.

[0016] The technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0017] In the embodiments of the present application, the position change amount of the catheter end is obtained according to the catheter steering instruction from the master controller, the position change amount comprising a direction angle and a bending angle; a driving wheel among the driving wheels is determined as a driving wheel and a driven wheel according to the position change amount, and an angle position change amount of the driving wheel is calculated; an angle position change amount of the driven wheel is calculated according to the angle position change amount of the driving wheel and a current position proportional distribution coefficient of the corresponding driven wheel, the current position proportional distribution coefficient being used to represent a proportion of a take-up length of the driving wheel to a pay-off length of the corresponding driven wheel in the current state; and the driving motor is controlled to drive the corresponding driving wheel to rotate according to the angle position change amount. The position change amount under the action of the catheter steering instruction is used for control instead of the target position, and the driving wheels are divided into the driving wheel and the driven wheel, only the angle position change amount of the driving wheel is directly calculated according to the position change amount, and the angle position change amount of the driven wheel is calculated according to the angle position change amount of the driving wheel, the angle position change amount calculation of the driven wheel is decoupled from the catheter steering instruction, so that the bending steering control of the catheter is realized, the calculation process of the angle position change amount of each driving wheel is simplified, and the response time of the catheter steering instruction is shortened.

[0018] Additional aspects and advantages will be better understood in connection with the following description and accompanying drawings. DETAILED DESCRIPTION

[0019] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments with reference made to the accompanying drawings. The drawings are for purposes of illustration only and serve to build a better understanding of the application. Numerous specific implementations have been discussed above with reference to the preferred embodiments. Nevertheless, it will be apparent to one of ordinary skill in the art that numerous other implementations can be constructed in accordance with the teachings of the application and that these implementations will vary from the preferred embodiments. For example, certain terminology has been used for the purpose of descriptive clarity in describing the preferred embodiments. It is intended that each specific term should be understood to encompass all possible alternatives to that specific term. For example, the term "a" should be understood to encompass the alternatives of "one or more" and the term "b" should be understood to encompass the alternatives of "two or more". Furthermore, the use of the term "about" in conjunction with a numerical value specifiy a range that is the numerical value ± 10 percent. In addition, the use of the term "comprise" has been used in the description and throughout the claims to mean that the compositions and methods encompass the recited items as well as those items falling within the four corners of the specification. Accordingly, various modifications and changes can be made to the preferred embodiments without departing from the scope of the present application.

[0020] Figure 1 A schematic diagram of a catheter system according to an embodiment of the present application is shown;

[0021] Figure 2 A schematic diagram of a catheter instrument and a power unit according to an embodiment of the present application is shown;

[0022] Figure 3 A schematic diagram of a catheter instrument according to an embodiment of the present application is shown;

[0023] Figure 4 A flowchart of a steering control method for a catheter tip according to an embodiment of the present application is shown;

[0024] Figure 5 A schematic diagram of determining the driving wheel and the driven wheel according to the direction angle when n = 3 and the driving wires are uniformly distributed in an embodiment of the present application is shown;

[0025] Figure 6 A schematic diagram of determining the driving wheel and the driven wheel according to the direction angle when n = 4 and the driving wires are uniformly distributed in an embodiment of the present application is shown;

[0026] Figure 7 A flowchart of calculating the angular position change amount of the driving wheel in a specific embodiment of the present application is shown;

[0027] Figure 8 A schematic diagram of a kinematic model established for a rotating section in an embodiment of the present application is shown;

[0028] Figure 9 A flowchart of calculating the angular position change amount of the driving wheel in another specific embodiment of the present application is shown;

[0029] Figure 10 A flowchart of calculating the angular position change amount of the driving wheel in yet another specific embodiment of the present application is shown;

[0030] Figure 11 A schematic diagram of the structure of a control system of a catheter system according to an embodiment of the present application is shown;

[0031] Figure 12 A schematic diagram of a computer readable storage medium is shown. DETAILED DESCRIPTION

[0032] Exemplary embodiments of the present application will be described herein below with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.

[0033] It should be noted that unless otherwise specified, technical or scientific terms used in the present application should be understood as having the commonly understood meanings as understood by one of ordinary skill in the art to which the present application pertains.

[0034] A catheter bending control method, a catheter system, a control system thereof, and a computer readable storage medium are described below in conjunction with the accompanying drawings.

[0035] Figure 1 A catheter system 1000 is shown. The catheter system 1000 includes an image cart 100, a trolley 200 and a master controller 300 connected to the image cart 100 respectively, a catheter instrument 400 which can be coupled to the trolley 200, a sensor system 500 connected to the trolley 200, and a control system 600 for realizing control among the catheter instrument 400, the master controller 300, the sensor system 500 and the image cart 100, etc. Among them, the master controller 300 can be connected to the trolley 200 by wire or wirelessly. When an operator performs various procedures on a patient beside the trolley 200, the operator can trigger a control instruction by operating the master controller 300, and control the catheter instrument 400 to advance, retract and bend, etc. through driving of the trolley 200.

[0036] The trolley 200 can be generally moved to the side of an operating bed for coupling the catheter instrument 400 and controlling the catheter instrument 400 to lift along a vertical direction, or to translate along a horizontal direction, or to move in a direction other than vertical and horizontal, under a control instruction, so as to provide a better preoperative preparation angle for operation of the catheter instrument 400. Among them, the control instruction can be an instruction triggered by the operator through operation of the master controller 300, or an instruction triggered by the operator directly by clicking or pressing a button provided on the trolley 200. Of course, in other embodiments, the control instruction can also be a voice control or an instruction triggered through a force feedback mechanism.

[0037] AsFigure 1 As shown, further, the trolley 200 can include a base 210, a sliding seat 220 that can move up and down along the base 210, and two mechanical arms 230 fixedly connected with the sliding seat 220. The mechanical arms 230 can include a plurality of arm segments coupled at joints, which provide the mechanical arms 230 with a plurality of degrees of freedom, for example, seven degrees of freedom corresponding to seven arm segments. The distal end of the mechanical arms 230 is equipped with a power unit (not shown in the figure), which is used to engage the catheter instrument 400 and control the distal end of the catheter instrument 400 to bend and turn correspondingly under the driving action of the power unit. Among them, the two mechanical arms 230 can be structures that are completely or partially the same, one mechanical arm 230 is used to engage the inner catheter instrument 410, and the other mechanical arm 230 is used to engage the outer catheter instrument 420. When installed, the outer catheter instrument 420 can be installed first, and after the outer catheter instrument 420 is installed, the catheter of the inner catheter instrument 410 is inserted into the catheter of the outer catheter instrument 420.

[0038] The sensor system 500 has one or more subsystems for receiving information about the catheter instrument 400. The subsystems can include a position sensor system, a shape sensor system for determining the position, orientation, velocity, speed, pose, and / or shape of the distal end of the catheter instrument 400 and / or along one or more segments of the catheter that can constitute the catheter instrument 400, and / or a visualization system for capturing images from the distal end of the catheter instrument 400.

[0039] The image cart 100 can be provided with a display system 110 and a flushing system (not shown in the figure) and the like. The display system 110 is used to display images or representations of the surgical site and the catheter instrument 400 generated by the subsystems of the sensor system 500. Real-time images of the surgical site and the catheter instrument 400 captured by the visualization system can also be displayed. Image data from imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), optical coherence tomography (OCT), and ultrasound, etc. can also be used to present images of the preoperative or intraoperative recorded surgical site. Preoperative or intraoperative image data can be presented as two-dimensional, three-dimensional or four-dimensional (e.g., based on time or based on speed information) images and / or as images from models created from preoperative or intraoperative image data sets, and virtual navigation images can also be displayed. In the virtual navigation images, the actual position of the catheter instrument 400 is registered with the preoperative images to present the virtual image of the catheter instrument 400 within the surgical site to the operator from the outside.

[0040] The control system 600 includes at least one memory and at least one processor. It can be understood that the control system 600 can be integrated in the trolley 200 or the imaging vehicle 100, or can be independently arranged. The control system 600 can support wireless communication protocols such as IEEE 802.11, IrDA, Bluetooth, HomeRF, DECT, and wireless telemetry, etc. The control system 600 can transmit one or more signals indicating the movement of the catheter instrument 400 by the powered portion moving the catheter instrument 400. The catheter instrument 400 can extend to the surgical position in the body via the opening of the natural cavity of the patient or the surgical incision.

[0041] Further, the control system 600 can include a mechanical control system (not shown in the figure) for controlling the movement of the catheter instrument 400, and thus can be integrated in the trolley 200, and an image processing system (not shown in the figure) for virtual navigation path planning, and thus can be integrated in the imaging vehicle 100. Of course, the various subsystems of the control system 600 are not limited to the specific cases listed above, and can be reasonably arranged according to actual conditions. Among them, the image processing system can use the above imaging technology to image the surgical site based on the images of the surgical site recorded before or during the operation. Software that can be used in combination with manual input can convert the recorded images into two-dimensional or three-dimensional composite images of part or the entire anatomical organ or segment. During the virtual navigation program, the sensor system 500 can be used to calculate the position of the catheter instrument 400 relative to the patient's anatomical structure, which can be used to generate external tracking images and internal virtual images of the patient's anatomical structure, realize the registration of the actual position of the catheter instrument 400 with the preoperative images, and thus the virtual image of the catheter instrument 400 in the surgical site can be presented to the operator from the outside.

[0042] The internal catheter instrument 410 and the external catheter instrument 420 have substantially the same structure and composition, and each has an elongated flexible internal catheter 41 and an external catheter 42. The diameter of the external catheter 42 is slightly larger than that of the internal catheter 41, so that the internal catheter 41 can pass through the external catheter 42 and provide certain support for the internal catheter 41, so that the internal catheter 41 can reach the target position in the patient's body to facilitate tissue or cell sampling and other operations from the target position.

[0043] Some movements of the master 300 can cause corresponding movements of the catheter instrument 400. For example, when the operator moves the direction dial of the master 300 upward or downward, the movement of the direction dial of the master 300 can be mapped to a corresponding pitch movement of the tip of the catheter instrument 400; when the operator moves the direction dial of the master 300 leftward or rightward, the movement of the direction dial of the master 300 can be mapped to a corresponding yaw movement of the tip of the catheter instrument 400. In the present embodiment, the master 300 can control the tip of the catheter instrument 400 to move within a 360° spatial range.

[0044] Figure 2 and Figure 3 A catheter instrument 400 provided by an embodiment of the present application is shown. The catheter instrument 400 is configured to be engaged with the powered part 240 of the robotic arm 230, and the catheter instrument 400 includes an instrument box 45 configured to be engaged with the powered part 240 and a catheter 48 connected with the instrument box 45. Here, the “engaged” means that when the instrument box 45 is mounted to the powered part 240, the driving force of the powered part 240 can be transmitted to the instrument box 45 and can cause the catheter 48 to normally move. For example, under the action of the driving force of the powered part 240, the tip of the catheter 48 can be bent and turned, etc.

[0045] The instrument box 45 includes a plurality of driving wheels 451 configured to be driven by the powered part 240 and a plurality of driving wires 452, and the powered part 240 includes a plurality of driving motors 241, and the driving motor 241, the driving wheel 451 and the driving wire 452 are one-to-one correspondingly arranged. Each driving wheel 451 is configured to be engaged with the corresponding driving motor 241, that is, when the instrument box 45 is mounted to the powered part 240, the corresponding driving motor 241 can drive the driving wheel 451 to rotate, and the corresponding driving wire 452 is wound on the driving wheel 451, and the active part of the corresponding driving wire 452, that is, the part not wound on the driving wheel 451, extends into the catheter 48, extends along the length direction of the catheter 48 and is finally fixed to the tip of the catheter.

[0046] In the present application, the tip can also be referred to as the distal end or the head, and the front end can also be referred to as the proximal end or the tail.

[0047] A part of the catheter 48 including the tip is a rotating section 49, and the tip of the rotating section 49 is the tip of the catheter 48. The rotating section 49 can be a joint assembly, which has high rigidity in the extension direction and has low rigidity in the bending direction, and can be bent under the control of the driving wire 452, so as to realize the turning of the catheter 48. In some embodiments, the joint assembly can be referred to as a snake bone.

[0048] In the plane of the rotating section 49 perpendicular to the length direction, the position of each driving wire 452 can be considered as fixed, while the driving wire 452 can be elongated or shortened along the length direction of the rotating section 49. The end of the driving wire 452 being fixed to the end of the rotating section 49 does not necessarily mean that the position of the end of the driving wire 452 is in the end plane of the rotating section 49. In actual application, in order to better protect the devices (such as endoscopes, surgical instruments, etc.) that can be carried by the catheter 48, the end of the driving wire 452 can be fixed at a position that is moved a small distance proximally from the end plane of the rotating section 49. In this case, if the ratio of the distance to the length of the rotating section 49 is less than a threshold value, the position of the end of the driving wire 452 can be considered as being in the end plane of the rotating section 49 during the steering of the end of the catheter 48.

[0049] The driving wheel 451 can be rotated clockwise or counterclockwise under the driving of the corresponding driving motor 241. If the driving wheel 451 rotates in a direction, more part of the corresponding driving wire 452 will be wound on the driving wheel 451, that is, part of the driving wire 452 originally belonging to the movable part enters the winding state, resulting in the length of the movable part being shortened. This process can also be referred to as pulling the driving wire 452 or paying out / rewinding. For ease of description, this direction is referred to as the forward direction. If the driving wheel 451 rotates in a direction, less part of the driving wire 452 will be wound on the driving wheel 451, that is, part of the driving wire 452 originally wound on the driving wheel 451 becomes the movable part, resulting in the length of the movable part being lengthened. This process can also be referred to as paying out. For ease of description, this direction is referred to as the reverse direction. Which of clockwise and counterclockwise is the forward direction and which is the reverse direction can be determined according to the winding direction of the corresponding driving wire 452.

[0050] The processor of the control system 600 is configured to perform the following steps to implement the steering control method of the end of the catheter provided in an embodiment of the present application. As shown in Figure 4 the method includes:

[0051] Step S11: According to the catheter steering instruction from the master controller, the position change amount of the end of the catheter is obtained.

[0052] The position change amount can include a direction angle a and a bending angle θ used to control the bending steering of the catheter. The user can operate at least one of the direction knobs, buttons, etc. input devices on the master controller to input the catheter steering instruction.

[0053] For example, the user can operate the direction dial in any direction in the operation plane, and the operation is converted into an electrical signal by the sensor in the main controller, i.e., a catheter steering instruction, which specifically includes a first voltage and a second voltage collected on two perpendicular axes of the main controller (i.e., the axes of the operation plane). The direction angle of the user operation is calculated according to the ratio of the first voltage to the second voltage, and specifically, the inverse tangent or inverse cotangent of the ratio can be calculated to obtain the direction angle of the user operation.

[0054] The square root of the sum of the squares of the first voltage and the second voltage is calculated as the combined value of the first voltage and the second voltage. The combined value reflects the force of the user operation, and the bending speed of the catheter tip can be calculated according to the combined value, for example, the product of the combined value and a preset coefficient can be calculated as the bending speed. The bending angle of the user operation is obtained by integrating the bending speed with respect to the command holding time, which is the duration of the same user operation.

[0055] The control interval, i.e., the interval between the steering control of the catheter tip, is determined. In some embodiments, there is only one catheter steering instruction in each control interval, and the sampling interval of the main controller is fixed, so the integration process can be omitted, and the bending angle θ of the user operation can be directly used as the bending speed.

[0056] To reduce the influence of the operator's shaking, the main controller's noise, etc., the collected first voltage and second voltage can be smoothed and filtered before calculating the direction angle and bending angle of the user operation.

[0057] The bending angle of the user operation can be directly used as the bending angle θ in the position change amount. Moreover, if the coordinate system of the operation plane is consistent with the coordinate system of the front end plane of the catheter rotation segment, i.e., the rotation angle between the two is 0, then the direction angle of the user operation can be directly used as the direction angle α in the position change amount, otherwise the direction angle of the user operation can be transformed according to the mapping relationship between the two coordinate systems to obtain the direction angle α.

[0058] Alternatively, in addition to the necessary angle transformation, in order to make the steering smoother and reduce the jump, the direction angle and bending angle of the user operation can be divided into multiple parts to obtain the direction angle α and bending angle θ in the position change amount. For example, the bending angle of the user operation is 30°, and the catheter steering instruction of this user input can be completed in 10 times, and the bending angle θ in the position change amount used each time is 3°.

[0059] Step S12: Determine the driving wheel and the driven wheel in the driving wheel according to the position change amount, and calculate the angular position change amount of the driving wheel.

[0060] For simplicity, the direction angle a in the position change amount is referred to as the direction angle change amount a, and the bending angle q in the position change amount is referred to as the bending angle change amount q in the following description. The direction angle and the bending angle input by the user are not necessarily the same as the direction angle change amount a and the bending angle change amount q.

[0061] To facilitate the description of the posture of the rotating section, coordinate systems are established for the front end plane and the end plane of the rotating section. For simplicity of calculation, the origins of the coordinate systems are the centers of the planes. The coordinates of a driving wire in the front end plane / end plane refer to the coordinates of the fixed position of the driving wire in the front end plane / end plane, and the angle refers to the included angle between the vector from the origin to the coordinates of the driving wire and the positive direction of the x-axis of the front end plane / end plane. The coordinates and the angle of the same driving wire in the two coordinate systems are consistent.

[0062] When the assembled catheter is in a natural state, i.e., in a state where the end is not steered, the coordinate system of the end plane of the rotating section is generally consistent with the coordinate system of the front end plane. During the steering of the end of the catheter, it can be considered that the coordinate system of the front end plane of the rotating section remains unchanged, and the coordinate system of the end plane changes under the action of the driving wire.

[0063] When the assembled catheter is in a natural state, the driving wires on each driving wheel can be maintained in a suitable state of tension. If a driving wire is pulled, the driving wire will drive the end of the catheter to bend and steer in the fixed direction, and the bending of the end of the catheter will pull part or all of the other driving wires. If the tension on the driving wire caused by the bending of the end of the catheter is large enough, the corresponding driving wheel will be driven to rotate in the opposite direction by a small distance, which is generally affected by the tension state and the elastic modulus of the driving wire. During the reverse rotation, the change in tension is discontinuous, and the jump in force will cause the speed of the corresponding driving wheel to jump, which may cause the wire to loosen. After the driving wire is pulled tight, if the corresponding motor does not drive the driving wheel to follow the rotation, the catheter will be stuck. If the tension on the driving wire caused by the bending of the end of the catheter is not enough to overcome the resistance to drive the corresponding driving wheel to rotate in the opposite direction, the driving wire will be pulled tight beyond the limit determined by the system parameters (such as mechanical structure and size, material properties, etc.), which will also cause the catheter to be stuck. The catheter being stuck means that the driving wheel cannot continue to pull the wire, which often causes the driving wheel to fail to rotate to the position indicated by the angle position change amount, and the end of the catheter cannot normally bend to the target position. Therefore, to enable the driving wheel to normally pull the wire, part or all of the driving wheels corresponding to the pulled driving wire need to follow the wire release as driven wheels.

[0064] Taking a pair of relatively set driving wheels as an example, the relative setting means that the line connecting the driving wires corresponding to the two driving wheels at the fixed position at the end of the catheter passes through the center of the plane of the catheter end, that is, the angular difference between the driving wires is π. When one of the driving wheels rotates forward as the active wheel to pull the wire, the other driving wheel needs to follow as the driven wheel to release the wire. A parameter can be defined - the position proportion distribution coefficient, which is used to express the ratio of the wire-retrieving length of the active wheel to the wire-releasing length of the corresponding driven wheel. For the specific content of this parameter, please refer to the description of the subsequent steps.

[0065] The number of drive wires is n, where n is an integer greater than 2. The n drive wires divide the front end plane of the catheter rotating section into n intervals in terms of angle. The drive wires corresponding to the two ends of the interval to which the angular variation α belongs can be used as active drive wires, and the drive wheels connected to the active drive wires are active wheels. Some or all of the remaining drive wheels are driven wheels. When judging the interval to which the angular variation α belongs, the endpoints of the interval are not included. If the angular variation α falls on a certain endpoint, that is, it has the same angle as a certain drive wire, only the drive wire can be selected as the active drive wire. In some embodiments, if the number and position of the drive wires support it, the number of active wheels can be greater than 2. When the active wheel is determined, some or all of the drive wheels other than the active wheel can be selected as driven wheels based on the number and position distribution of the drive wires.

[0066] The following examples illustrate how to identify the driving and driven wheels. To simplify the description, the following examples show the same serial numbers for the drive wires, drive wheels, and motors, but they may differ in practice. The drive wires are evenly distributed, but they may not be evenly distributed in practice.

[0067] Example 1:

[0068] In this example, n=3 and the driving wires are evenly distributed. The angles of the driving wires 1, 2, and 3 in the front plane coordinate system of the rotating segment are 0, 2π / 3, and 4π / 3, respectively.

[0069] If the direction angle change is one of 0, 2π / 3, and 4π / 3, the driving wheel connected by the driving wire with the same angle as the direction angle change is the active wheel, and the remaining two driving wheels are driven wheels.

[0070] If the direction angle change , that is, falling into Figure 5 The shaded area in part A indicates that driving wheels 1 and 2 are active wheels, and driving wheel 3 is the driven wheel.

[0071] If the direction angle change , that is, falling into Figure 5 As shown in the shadow of part B, driving wheels 2 and 3 are active wheels, and driving wheel 1 is the driven wheel.

[0072] If the direction angle change is one of 0, π / 2, π, 3π / 2, the drive wheel connected with the drive wire whose angle is the same as the direction angle change is the driving wheel, and the drive wheel arranged opposite to the driving wheel is the driven wheel. For example, if the direction angle change is π / 2, the drive wheel 6 is the driving wheel, and the drive wheel 8 is the driven wheel, and the drive wheels 5 and 7 are neither the driving wheel nor the driven wheel, i.e. no need to rotate. If the direction angle change falls into the shadow of the A part of the figure, the drive wheels 5 and 6 are the driving wheels, and the drive wheels 7 and 8 are the driven wheels. Figure 5

[0073] Example two:

[0074] In this example, n=4 and the drive wires are uniformly distributed, and the angles of the drive wires 5, 6, 7 and 8 in the front end plane coordinate system of the rotating section are 0, π / 2, π and 3π / 2 respectively.

[0075] If the direction angle change is one of 0, π / 2, π, 3π / 2, the drive wheel connected with the drive wire whose angle is the same as the direction angle change is the driving wheel, and the drive wheel arranged opposite to the driving wheel is the driven wheel. For example, if the direction angle change is π / 2, the drive wheel 6 is the driving wheel, and the drive wheel 8 is the driven wheel, and the drive wheels 5 and 7 are neither the driving wheel nor the driven wheel, i.e. no need to rotate.

[0076] If the direction angle change falls into the shadow of the A part of the figure, the drive wheels 5 and 6 are the driving wheels, and the drive wheels 7 and 8 are the driven wheels. If the direction angle change falls into the shadow of the B part of the figure, the drive wheels 6 and 7 are the driving wheels, and the drive wheels 8 and 5 are the driven wheels. Figure 6 If the direction angle change falls into the shadow of the C part of the figure, the drive wheels 7 and 8 are the driving wheels, and the drive wheels 5 and 6 are the driven wheels.

[0077] If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels. Figure 6 If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels.

[0078] If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels. If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels. Figure 6 If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels.

[0079] If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels. Figure 6 If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels.

[0080] If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels. If the direction angle change falls into the shadow of the D part of the figure, the drive wheels 8 and 5 are the driving wheels, and the drive wheels 6 and 7 are the driven wheels. ​​​​If the angle of the driving wire is the same as the angle of the driving wire, the driving wheel corresponding to the driving wire can be selected as the driven wheel, and the angle is the same as the direction angle change The driving wheels corresponding to the two closest driving wires are the driving wheels, and the angle is the opposite angle of the direction angle change And If the angle of any driving wire is different from the angle of any driving wire, the angle can be selected as the direction angle change The driving wheels corresponding to the two closest driving wires are the driving wheels, and the angle is the opposite angle of the direction angle change The driving wheels corresponding to the two closest driving wires are the driving wheels. The unselected driving wheels do not need to move.

[0081] If the direction angle change is If the angle of the driving wire is the same as the angle of the driving wire, the driving wheel corresponding to the driving wire can be selected as the driving wheel, and the angle is the opposite angle of the direction angle change The driving wheels corresponding to the same driving wire are the driving wheels; if the direction angle change is If the angle of any driving wire is different from the angle of any driving wire, the angle can be selected as the direction angle change The driving wheels corresponding to the two closest driving wires are the driving wheels, and the angle is the opposite angle of the direction angle change The driving wheels corresponding to the two closest driving wires are the driving wheels. The unselected driving wheels do not need to move.

[0082] In addition, there is a special case of n = 2, i.e. two driving wires are oppositely arranged. In this case, the direction angle change of the driving wire controlling the rotation of the catheter tip is actually only the angle of one of the two driving wires. The driving wheel corresponding to the driving wire with the same angle as the direction angle change is the driving wheel, and the other driving wheel is the driven wheel.

[0083] Generally, under the action of the driving wire, the rotating section / catheter tip can bend in two degrees of freedom, and the state / pose of the rotating section / catheter tip can be described by two joint variables, i.e. bending angle and direction angle. Generally, the direction angle is used to describe the direction in which the rotating section / catheter tip bends, and the size of its value range can be 2π. The specific range can be determined according to actual needs, for example, [0, 2π], [-π, π] and the like. The bending angle is used to describe the bending degree of the rotating section / catheter tip, and the lower limit of its value range can be 0, indicating the natural state of no bending. The upper limit can be determined according to actual conditions, and generally does not exceed π, for example, π / 2, 2π / 3 and the like.

[0084] Under the action of the position change amount, the catheter tip transforms from the current state to the target state, that is, transforms from the current pose to the target pose. In the catheter steering control, the transformation of the catheter tip from the current position to the target position is mainly concerned, and the length change of the active driving wire, that is, the take-up length of the active wheel, is calculated according to the transformation, and the angular position change amount of the active wheel is calculated. The specific calculation process of the angular position change amount of the active wheel is illustrated below in combination with the drawings.

[0085] As shown in the specific embodiment of the present application, the calculation of the angular position change amount of the active wheel includes the following sub-steps: Figure 7

[0086] S101: Calculate the position increment offset of the catheter tip under the action of the position change amount.

[0087] Due to the structural design of the rotating section, in the process of bending steering, the rotating section can be approximately treated as a circular arc. A kinematic model can be established for the rotating section based on this characteristic, and the position increment offset is calculated based on the kinematic model.

[0088] For example, a kinematic model as shown in Figure 8 may be established for the rotating section, wherein the length of the rotating section is L, and the rotating section is abstracted as a circle with a radius r in the direction perpendicular to the length. The coordinate system of the front end of the rotating section is , the xoy plane is the front end plane and the origin is the center of the front end plane, which can be treated as fixed during the rotation process, and plays a role similar to the world coordinate system. The coordinate system of the end of the rotating section in the current state is , the xoy plane is the end plane and the origin is the center of the end plane. The transformation of the coordinate system of the end of the rotating section in the current state relative to the coordinate system of the front end can be described by the current direction angle and the current bending angle . More specifically, the current bending angle is the circular arc angle of the length L circular arc formed by the center of the front end plane to the center of the end plane in the current state, and the current direction angle is the rotation angle of the xoy plane of the coordinate system of the end relative to the xoy plane of the coordinate system of the front end in the current state. Based on the model, in the Cartesian coordinate system, the transformation matrix of the coordinate system of the end relative to the coordinate system of the front end in the current state can be represented as:

[0089]

[0090] wherein represents the pose transformation of the coordinate system of the end relative to the coordinate system of the front end in the current state; ​The position transformation of the end coordinate system relative to the front coordinate system in the current state can be represented by a vector pointing from the center of the front plane to the center of the end plane in the current state.

[0091] The current direction angle is calculated The sum of the direction angle in the position change and The target direction angle is calculated The current bending angle is calculated The sum of the bending angle in the position change and The target bending angle is calculated In practical applications, if the calculated target direction angle exceeds the set value range, it can be added by 2π or subtracted by 2π to return to the value range; if the calculated target bending angle is greater than the upper limit of the bending angle value range, it can be corrected to the upper limit of the bending angle value range; if the calculated target bending angle is negative, the target direction angle is added by π or subtracted by π according to the value range of the direction angle to become its opposite direction, and the target bending angle is modified to its absolute value.

[0092] In the Cartesian coordinate system, the transformation matrix of the end coordinate system relative to the front coordinate system in the target state can be represented as:

[0093]

[0094] Wherein represents the pose transformation of the end coordinate system relative to the front coordinate system in the target state; represents the position transformation of the end coordinate system relative to the front coordinate system in the target state, which can be represented by a vector pointing from the center of the front plane to the center of the end plane in the target state.

[0095] According to the position transformation in the current state and the position transformation in the target state, the position increment offset can be calculated, which can be represented by a vector pointing from the center of the end plane in the current state to the center of the end plane in the target state.

[0096] S102: Calculate the take-up length of each driving wheel according to the position increment offset.

[0097] The position increment offset describes the transformation of the catheter tip from the current position to the target position. The driving wires can be added to the kinematic model described above, and the fixed position of each driving wire is set on a circle perpendicular to the length direction. The driving wires can be processed as a straight line, a circular arc, a multi-segment polyline, or a multi-segment arc in the length direction. In the discussion of the kinematic model, the driving wires mentioned generally refer to the driving wires in the rotation section, except for the parts specifically indicated. According to the kinematic model, the mapping function between the position increment offset and the take-up length of the active wheel (i.e., the shortening amount of the active driving wire) can be calculated, and the take-up length of each active wheel can be calculated by substituting the position increment offset obtained in S101.

[0098] The mapping function can be an analytical solution calculated according to the kinematic model, or a function obtained by processing the analytical solution in an approximate, fitting, or other manner for the purpose of simplifying the calculation.

[0099] S103: Calculate the angular position change amount of the corresponding active wheel according to the take-up length of the active wheel.

[0100] Specifically, the angular position change amount can be calculated according to the geometric parameters of the driving wheel (such as the winding radius of the driving wire) and the take-up length of the active wheel, and the rotation direction of the active wheel (clockwise or counterclockwise) can be determined according to the winding direction of the driving wire. The combination of the two can obtain the angular position change amount of the active wheel.

[0101] As shown in the other specific embodiment of the present application, Figure 9 the calculation of the angular position change amount of the active wheel includes the following sub-steps:

[0102] S111: Obtain the kinematic model of the rotation section.

[0103] S112: Calculate the length difference of the active driving wire between the current state and the target state under the action of the position change amount as the take-up length of the active wheel according to the kinematic model.

[0104] Still taking the kinematic model shown in Figure 8 as an example, the number of driving wires is 4 and they are uniformly distributed, and each driving wire is abstracted as a straight line for processing. Figure 8 The lower plane of the middle is the front end plane, denoted as i-1, B1, B2, B3, and B4 are the fixed points of driving wires 1, 2, 3, and 4 on the front end plane, respectively, and O is the center of the front end plane. For the convenience of calculation, OB1 is defined as the positive direction of the x-axis of the front end coordinate system, OB2 is defined as the positive direction of the y-axis of the front end coordinate system, and the z-axis of the front end coordinate system is perpendicular to the front end plane and points to the tip plane. Figure 8The plane in the upper side is the end plane, denoted as i, P1, P2, P3 and P4 are the fixed points of driving wires 1, 2, 3 and 4 on the end plane respectively, C is the center of the end plane, for the convenience of calculation, CP1 is defined as the positive direction of the x-axis of the end coordinate system, CP2 is defined as the positive direction of the y-axis of the end coordinate system, and the z-axis of the end coordinate system is perpendicular to the end plane and points to the side away from the front end plane.

[0105] According to the model, the current state The length of the jth driving wire is:

[0106]

[0107]

[0108] Where j = 1, 2, 3, 4.

[0109] The target state is substituted into the above formula, the target state The length of the jth driving wire is:

[0110]

[0111]

[0112] According to the number of the driving wheel determined in the foregoing, the length change of the driving wire between the current state and the target state is calculated as the take-up length of the driving wheel. If the driving wheel numbered j is the driving wheel, the take-up length directly calculated according to the kinematic model is .

[0113]

[0114] The above formula can be processed in the manner of approximation, fitting, etc. to simplify the calculation.

[0115] S113: Calculate the angular position change of the driving wheel according to the take-up length of the driving wheel.

[0116] Specifically, the numerical value of the angular position change can be calculated in combination with the geometric parameters of the driving wheel (such as the winding radius of the driving wire) and the take-up length of the driving wheel, and the rotation direction (clockwise or counterclockwise) of the driving wheel can be determined according to the winding direction of the driving wire, and the combination of the two can obtain the angular position change of the driving wheel.

[0117] As shown in Figure 10 , in another specific embodiment of the present application, calculating the angular position change of the driving wheel comprises the following sub-steps:

[0118] S121: Calculate the take-up length of a single wheel according to at least the bending angle.

[0119] The calculation of the wire length in the present embodiment is further decomposed. If the direction angle change amount is consistent with the angle of a certain driving wire, only the driving wheel corresponding to the driving wire is selected as the driving wheel, and in this case, the wire length of the driving wheel is the single-wheel wire length. The single-wheel wire length is not affected by the actual direction angle change amount, and can be determined by the current bending angle and the bending angle change amount at the end of the rotation section.

[0120] Still taking the motion model shown in FIG. 6 as an example, the specific description of the motion model can refer to the related content of the foregoing embodiments. The single-wheel wire length directly calculated according to the model is Figure 8

[0121]

[0122] The above formula can be processed in the manner of approximation, fitting, etc. to simplify the calculation.

[0123] S122: Calculate the wire length of each driving wheel according to the single-wheel wire length and the direction angle.

[0124] In actual control, the direction angle change amount is often not consistent with the angle of the driving wire, and two driving wheels need to cooperate to control the catheter end to turn according to the direction angle change amount. The single-wheel wire length can be mapped to the wire length of each driving wheel according to the included angle between the direction angle change amount and each driving wire.

[0125] S123: Calculate the angle position change amount of the corresponding driving wheel according to the wire length of the driving wheel.

[0126] Specifically, the angle position change amount can be calculated according to the geometric parameters of the driving wheel (such as the winding radius of the driving wire) and the wire length of the driving wheel, and the rotation direction (clockwise or counterclockwise) of the driving wheel can be determined according to the winding direction of the driving wire, and the angle position change amount of the driving wheel can be obtained by combining the two.

[0127] In the above example of the kinematic model, the driving wire is treated as a straight line, but the model has errors compared with the actual situation, and the errors will be enlarged in a nonlinear manner as the bending angle of the rotation section / catheter end increases. In order to improve the accuracy of the steering control, a more complex but more accurate kinematic model can be selected, such as treating the driving wire as a multi-segment polyline / multi-segment arc, treating the rotation section as a multi-segment circular arc, etc. In addition, other calculation methods other than the kinematic model can be introduced as needed to modify the calculation formula of the wire length and / or correct the results calculated by the model.

[0128] ​​The calculation methods given above can be used alternatively or in combination. For example, according to the selection of the bending angle segmentation, one of the calculation methods can be selected, and how to segment the bending angle and / or the corresponding calculation method of each segment can be determined through experiments to meet the accuracy and / or real-time requirement of the steering control.

[0129] Step S13: Calculate the angular position change amount of the driven wheel according to the angular position change amount of the driving wheel and the current position proportion distribution coefficient of the corresponding driven wheel.

[0130] The position proportion distribution coefficient is used to represent the proportion of the take-up length of the driving wheel to the pay-out length of the corresponding driven wheel. For a catheter equipped with n driving wheels, theoretically each driving wheel can have n-1 position proportion distribution coefficients, respectively representing the position proportion distribution coefficient of itself as a driven wheel when other driving wheels are driving wheels. For the i-th driving wheel, its position proportion distribution coefficient can be represented as a set [k ij ], i, j = 1, …, n and i≠j. In practical applications, according to the number of driving wheels and the position distribution of the corresponding driving wires, some position proportion distribution coefficients can be fixed as 0 for processing, in which case these position proportion distribution coefficients can be omitted from the set. For example, in the case of n = 4 and uniform distribution of driving wires, the position proportion distribution coefficients between the driving wheels corresponding to adjacent driving wires can be fixed as 0 for processing, and only the position proportion distribution coefficients between the driving wheels arranged opposite to each other are retained.

[0131] If the rotation segment can be treated as a rigid body, the position proportion distribution coefficient is a constant. However, the deformation of the rotation segment during movement is often not negligible, and the actual position proportion distribution coefficient is nonlinearly changed. To more accurately describe the position proportion distribution coefficient, the current position proportion distribution coefficient is defined to represent the proportion of the take-up length of the driving wheel to the pay-out length of the corresponding driven wheel in the current state.

[0132] If the current position proportion distribution coefficient is the ratio of the pay-out length of the corresponding driven wheel to the take-up length of the driving wheel, the angular position change amount of the driven wheel can be the sum of the angular position change amount of the corresponding driving wheel of the driven wheel and the product of the current position proportion distribution coefficient.

[0133] The calculation function of the angular position change amount of the driven wheel can be independent or combined with the calculation function of the angular position change amount of the driving wheel. For example, if the position increment offset is used for calculation, a combined function, the angle increment distribution function, can be set for all driving wheels. The input of the function can include the current position proportion distribution coefficient, the direction angle of the position change amount and a position increment offset, according to the input, the function can determine the driving wheel and the driven wheel, calculate the angular position change of the driving wheel and the angular position change of the driven wheel, and finally output the angular position change of each driving wheel.

[0134] Before this step, the current position proportion distribution coefficient can be obtained. The current bending angle of the catheter tip is input into the pre-stored mapping relationship to obtain the current position proportion distribution coefficient of the driven wheel. The output of the mapping relationship includes the current position proportion distribution coefficient, and the input at least includes the current bending angle.

[0135] A plurality of groups of test samples can be collected in advance, and the samples can be processed by segmentation function, curve (for example, polynomial) fitting, neural network training, etc. to obtain the mapping relationship. During the collection process of the samples, the driven wheel can be adjusted to a suitable position (i.e., a position that meets the pay-off condition) by manual control, and then the angular position of the driven wheel is recorded to calculate the pay-off length / angular position change. The pay-off condition can include that the driving wheel moves to the target position and the driven driving wire wound on the driven wheel maintains a suitable tension state.

[0136] According to the structural design of the rotating section, the nonlinear change of the position proportion distribution coefficient is sensitive to the bending angle. Each group of samples includes at least one of the current bending angle, the bending angle change of this movement, and the target bending angle, at least one of the take-up length, the angular position change, and the angular position of the driving wheel, and at least one of the pay-off length, the angular position change, and the angular position of the driven wheel. Of course, the direction angle can be introduced into the independent variable of the mapping relationship. At this time, the samples can further include at least one of the current direction angle, the direction angle change of this movement, and the target direction angle.

[0137] For example, in the case of n=4 and uniform distribution of driving wires, one driving wire can be selected, and the driving wire is stretched alone from the natural state until the set maximum range of the bending angle is reached. During this process, a plurality of groups of samples are collected, each group of samples including the angular position of the driving wheel, the angular position of the driven wheel, and the current bending angle. For the mth group of samples, the difference between the angular positions of the driving wheel and the driven wheel in the m-1th group of samples can be calculated, and the ratio of the difference between the angular positions of the driven wheel to the difference between the angular positions of the driving wheel is calculated as the current position proportion distribution coefficient of the mth group of samples. The mapping relationship can be selected in the form of a high-order polynomial, the input is the current bending angle, and the output is the current position proportion distribution coefficient. A plurality of groups of samples are used to determine the coefficients of each term in the polynomial to obtain the final mapping relationship for subsequent control.

[0138] Step S14: controlling the driving motor to drive the corresponding driving wheel to rotate according to the angular position change.

[0139] The angular position change amount of the corresponding drive motor can be calculated according to the angular position change amount of the drive wheel obtained in S13 based on the manner of engagement between the drive wheel and the corresponding drive motor.

[0140] The drive motor can have three basic control modes: position control, speed control, and current control (which can also be referred to as torque control or twist control). The position control can be selected, in which case the control quantity of the drive motor is the angular position, the sum of the current angular position and the angular position change amount of the drive motor can be calculated as the target angular position, and the controller of the drive motor is sent; or the angular position change amount of the drive motor can be directly sent to the controller of the drive motor. Or the speed control can be selected, in which case the control quantity of the drive motor is the angular velocity, and the angular position change amount of the drive motor divided by the control interval can obtain the angular velocity, and the controller of the drive motor is sent.

[0141] In addition, the drive motor generally uses three-loop control, from the inside out, the current loop, the speed loop and the position loop, and the output of the outer loop is the input of the adjacent inner loop. The controller of the drive motor can complete the three-loop control by itself, or part or all of the three loops can be processed by the upper computer (the processor of the control system 600 in the present application). For example, in the case of originally using the angular position as the control quantity, the position loop of the motor control can be processed by the upper computer, and the angular velocity after the position loop is processed by the processor is sent to the controller of the drive motor.

[0142] By implementing the embodiment, the position change amount under the action of the catheter steering instruction is used for control instead of the target position, and the drive wheel is divided into the driving wheel and the driven wheel, only the angular position change amount of the driving wheel is directly calculated according to the position change amount, and the angular position change amount of the driven wheel is calculated according to the angular position change amount of the driving wheel, the decoupling of the angular position change amount of the driven wheel and the catheter steering instruction is realized, so that the bending steering control of the catheter is realized while the calculation process of the angular position change amount of each drive wheel is simplified, and the response time of the catheter steering instruction is shortened.

[0143] The present application also provides a control system of a catheter system. Please refer to Figure 11 which shows the structure schematic diagram of the control system of the catheter system provided by an embodiment of the present application. As Figure 11 shown, the control system 600 includes a processor 60, a memory 61, a bus 62 and a communication interface 63, the processor 60, the communication interface 63 and the memory 61 are connected through the bus 62; the memory 61 stores computer program instructions executable by the processor 60, and the processor 60 executes the computer program instructions to execute the steering control method of the catheter end provided by any of the preceding embodiments of the present application.

[0144] The memory 61 can include a high-speed random access memory (RAM) and can also include a non-volatile memory, such as at least one disk memory. The communication connection between the apparatus network element and at least one other network element is realized through at least one communication interface 63 (which can be wired or wireless), and the Internet, a wide area network, a local network, a metropolitan area network, etc. can be used.

[0145] The bus 62 can be an ISA bus, a PCI bus, an EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The memory 61 is used to store programs, and the processor 60 executes the programs after receiving execution instructions. The catheter tip steering control method disclosed in any of the embodiments of the present application can be applied to the processor 60 or implemented by the processor 60.

[0146] The processor 60 can be an integrated circuit chip with signal processing capability. In the implementation process, each step of the above method can be completed by integrated logic circuits or instructions in the form of software in the processor 60. The processor 60 described above can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a ready-to-program gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. Each method, step and logic block disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as a hardware coding processor for execution, or a combination of hardware and software modules in the coding processor for execution. The software module can be located in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an electrically erasable programmable memory, a register, or other mature storage media in the art. The storage medium is located in the memory 61, and the processor 60 reads the information in the memory 61 and combines the hardware to complete the steps of the above method.

[0147] The electronic device provided by the embodiments of the present application and the catheter tip steering control method provided by the embodiments of the present application have the same beneficial effects as the methods they adopt, run or implement.

[0148] The embodiments of the present application also provide a computer-readable storage medium corresponding to the catheter tip steering control method provided by the preceding embodiments. Please refer toFigure 12 a computer readable storage medium 6 shown, on which computer program instructions are stored, which, when executed by a processor, implement the catheter tip steering control method provided by any of the preceding embodiments.

[0149] It should be noted that examples of the computer readable storage medium can include, but are not limited to, optical discs, phase change memories (PRAM), static random access memories (SRAM), dynamic random access memories (DRAM), other types of random access memories (RAM), read-only memories (ROM), electrically erasable programmable read-only memories (EEPROM), flash memories, or other optical, magnetic storage media, which are not listed one by one here.

[0150] The computer readable storage medium provided by the above embodiments of the present application and the catheter tip steering control method provided by the embodiments of the present application are based on the same inventive concept, and have the same beneficial effects as the method adopted, run or implemented by the application program stored therein.

[0151] It should be noted that:

[0152] In the specification provided herein, a large number of specific details are described. However, it can be understood that the embodiments of the present application can be practiced without these specific details. In some examples, well-known structures and techniques are not shown in detail in order not to obscure the understanding of the present specification.

[0153] Similarly, it should be appreciated that the individual features of the application described in the above description of the exemplary embodiments of the application are, to the extent possible, individually as well as in combination protected, in particular, in one or more of the claims below. In addition, it should be understood that any feature described in relation to any aspect or embodiment of the present application can be applicable to any other aspect or embodiment of the application, in particular, if it is not explicitly mentioned that the feature is not applicable to all aspects or embodiments.

[0154] Furthermore, those skilled in the art will appreciate that a combination of features of different embodiments can be meant to be within the scope of the application and form a different embodiment. For example, in the claims below, any one of the claimed embodiments can be used in any combination.

[0155] The above description is only the preferred embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A catheter system, characterized by The catheter system comprises a mechanical arm, a catheter instrument engaged with a power part of the mechanical arm, a master controller in communication connection with the mechanical arm, and a processor, the catheter instrument comprises an instrument box arranged to be engaged with the power part and a catheter connected with the instrument box, the instrument box comprises a driving wheel arranged to be driven by the power part and a driving wire having one end wound on the driving wheel and the other end extending along the catheter and fixed to the catheter tip, the power part comprises a plurality of driving motors, the driving motors, the driving wheels and the driving wires correspond to each other one by one, and the processor is configured to perform the following steps: According to the catheter steering instruction from the master controller, the position change amount of the catheter tip is obtained, and the position change amount comprises a direction angle and a bending angle; According to the position change amount, the driving wheels of the driving wheels are determined, and the angle position change amount of the driving wheel is calculated; The current bending angle of the catheter tip is input into the pre-stored mapping relationship to obtain the corresponding current position proportional distribution coefficient of the driven wheel, and the input of the mapping relationship at least comprises the current bending angle; According to the angle position change amount of the driving wheel and the corresponding current position proportional distribution coefficient of the driven wheel, the angle position change amount of the driven wheel is calculated, and the current position proportional distribution coefficient is used to represent the proportion of the take-up length of the driving wheel and the pay-off length of the corresponding driven wheel in the current state; The driving motor drives the corresponding driving wheel to rotate according to the angle position change amount.

2. The catheter system of claim 1, wherein, The number of the driving wires is n, n is an integer greater than 2, and the n driving wires divide the front end plane of the catheter rotating section into n intervals in angle, and the driving wires corresponding to the two ends of the interval to which the direction angle belongs are the driving driving wires, the driving wheels connected with the driving driving wires are the driving wheels, and part or all of the remaining driving wheels are the driven wheels.

3. The catheter system of claim 2, wherein, The processor is configured to perform the following specific steps: The position increment offset of the catheter tip under the action of the position change amount is calculated; The take-up length of each driving wheel is calculated according to the position increment offset; The angle position change amount of the driving wheel is calculated according to the take-up length of the driving wheel.

4. The catheter system of claim 2, wherein, The processor is configured to perform the following specific steps: The kinematic model of the rotating section is obtained; The length difference of the driving driving wire in the current state and in the target state under the action of the position change amount is calculated as the take-up length of the driving wheel according to the kinematic model; The angle position change amount of the driving wheel is calculated according to the take-up length of the driving wheel.

5. The catheter system of claim 2, wherein, The processor is configured to perform the following specific steps: The single-wheel take-up length is calculated at least according to the bending angle; The take-up length of each driving wheel is calculated according to the single-wheel take-up length and the direction angle; The angle position change amount of the driving wheel is calculated according to the take-up length of the driving wheel.

6. The catheter system of claim 1, wherein, The angle position change amount of the driven wheel is the sum of the angle position change amount of the corresponding driving wheel of the driven wheel and the current position proportional distribution coefficient.

7. The catheter system of claim 1, wherein, The catheter steering instruction includes a first voltage and a second voltage collected on two mutually perpendicular axes of the master controller, the direction angle is calculated according to a ratio of the first voltage and the second voltage, and the bending angle is calculated by integrating a bending speed with respect to a command holding time, the bending speed being calculated according to a combined value of the first voltage and the second voltage.

8. A method of steering control of a catheter tip, characterized by, The method comprises: According to the catheter steering instruction from the master controller, obtaining a position change amount of the catheter end, the position change amount including a direction angle and a bending angle; According to the position change amount, determining a driving wheel and a driven wheel in a plurality of driving wheels, and calculating an angular position change amount of the driving wheel, the driving wheel being one-to-one corresponding to a driving motor and a driving wire, the driving wire being wound on the driving wheel and being driven by the corresponding driving motor, the other end of the driving wire extending along the catheter and being fixed to the catheter end; Inputting the current bending angle of the catheter end into a pre-stored mapping relationship to obtain a corresponding current position proportional distribution coefficient of the driven wheel, the input of the mapping relationship including at least the current bending angle; According to the angular position change amount of the driving wheel and the current position proportional distribution coefficient of the corresponding driven wheel, calculating the angular position change amount of the driven wheel, the current position proportional distribution coefficient being used to represent a proportion of the take-up length of the driving wheel to the pay-off length of the corresponding driven wheel in the current state; Controlling the driving motor to drive the corresponding driving wheel to rotate according to the angular position change amount. 9.A computer readable storage medium, the computer readable storage medium storing computer program instructions configured to be loaded and executed by a processor to implement the steps of the method of claim 8.

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