A 3D modeling system and method based on force detection feedback

Abstract

This invention proposes a 3D modeling system and method based on force detection feedback. The 3D modeling system includes: a calibration guide tube, a 3D calibration system, a force-sensing actuator arm, a controller, a workstation computer, and main control system software. The calibration guide tube is adapted to be fixed to the force-sensing actuator arm, which has a motor power module and a measurement module. The measurement module is used to measure the operating parameters of the motor power module. The main control system software is installed on and connected to the workstation computer and stores a calibration matrix. The calibration matrix records the correspondence between the contact force of the calibration guide tube and the operating parameters. During the 3D modeling process, the workstation computer receives the operating parameters measured by the measurement module and obtains the contact force of the calibration guide tube by querying and comparing with the calibration matrix. This invention can achieve force detection using existing high-density calibration guide tubes, significantly reducing cost and system complexity. The method of inferring the force at the guide tube tip from the operating parameters is accurate and has a fast response speed.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a three-dimensional modeling system and method based on force detection feedback. Background Technology

[0002] Three-dimensional interventional cardiac therapy is a minimally invasive surgical procedure guided by medical images, using a catheter to map and treat lesions inside the heart. In traditional surgery, the surgeon manually manipulates the mapping catheter, relying on touch to determine the contact between the catheter tip and the heart chamber wall to acquire electrical signals and construct a three-dimensional model. This method is highly dependent on the surgeon's experience and has the following problems:

[0003] 1. The judgment of contact force is highly subjective, and novice doctors need long-term training to master it;

[0004] 2. Inaccurate modeling or poor catheter placement can lead to inaccurate modeling and affect surgical outcomes.

[0005] 3. Existing force detection solutions mostly rely on force sensors integrated at the catheter tip, which are costly, complex in structure, and not suitable for disposable consumables.

[0006] Chinese patent CN 113425402 A describes a catheter and ablation system capable of determining balloon apposition. This system uses a pressure sensor to detect parameter changes within the balloon septum to determine apposition status. While this method can reflect apposition to some extent, the sensors used are expensive, increasing surgical costs for patients. Furthermore, due to limitations in the diameter of interventional devices, integrating the sensors faces challenges related to size, signal transmission, and power supply, limiting its practicality.

[0007] Therefore, there is an urgent need for a force detection feedback system and method that can automatically complete three-dimensional modeling of the heart chamber without changing the existing catheter structure, is low-cost, high-precision, and does not require alteration of the existing catheter structure. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to address the difficulties in objectively and accurately judging the contact force between the catheter and the cardiac cavity tissue, the reliance on experience, the low degree of automation, and the high cost and complex structure of integrated force sensor solutions in the existing technology. The present invention proposes a three-dimensional modeling system and method based on force detection feedback.

[0009] A force-detection feedback-based 3D modeling system according to an embodiment of the present invention includes:

[0010] Mapping catheter;

[0011] A three-dimensional mapping system, which is communicatively connected to the mapping conduit, is used to perform three-dimensional modeling of the object under test based on the measurement information of the mapping conduit;

[0012] A force-sensing actuator arm is provided, wherein the calibration conduit is adapted to be fixed to the force-sensing actuator arm so that the movement of the calibration conduit is driven by the force-sensing actuator arm; the force-sensing actuator arm has a motor power module and a measurement module, wherein the measurement module is used to measure the operating parameters of the motor power module;

[0013] The controller is used to input control commands to control the movement of the mapping catheter;

[0014] The workstation computer is connected to both the force-sensing actuator and the controller. The workstation computer receives the control commands to control the force-sensing actuator to drive the movement of the mapping catheter.

[0015] The main control system software is installed on a workstation computer and stores a calibration matrix, which records the correspondence between the contact force of the calibration catheter and the operating parameters.

[0016] During the 3D modeling process, the workstation computer receives the operating parameters measured by the measurement module and obtains the contact force of the calibration catheter by querying and comparing the calibration matrix.

[0017] According to the force detection feedback-based 3D modeling system of the present invention, there is no need to integrate expensive force sensors at the tip of the mapping catheter. Force detection can be achieved using existing high-density mapping catheters, which significantly reduces costs and system complexity. The present invention infers the force at the tip of the catheter by monitoring the operating parameters of the force-sensing actuator motor power module, which is accurate and has a fast response speed.

[0018] According to some embodiments of the present invention, the operating parameters include input current and output torque. The measurement module is used to measure the input current and / or output torque of the motor power module. The calibration matrix records the correspondence between the contact force of the calibration conduit and the input current and / or the output torque. During the three-dimensional modeling process, the workstation computer obtains the contact force of the calibration conduit by querying and comparing the received input current and / or output torque through the calibration matrix.

[0019] In some embodiments of the present invention, the calibration matrix includes: a record of the correspondence between the contact force of the mapping catheter in a static state and the operating parameters, and the correspondence between the contact force of the mapping catheter in a moving state and the operating parameters.

[0020] According to some embodiments of the present invention, the force-sensing actuator further includes: a current adaptive control module, connected to the main control computer, for adaptively adjusting the input current of the motor power module according to the control command of the controller.

[0021] In some embodiments of the present invention, the mapping duct is equipped with a three-dimensional magnetic positioning sensor and a ring electrode electrical positioning sensor to collect spatial coordinate information and feed it back to the three-dimensional mapping system for three-dimensional modeling.

[0022] According to some embodiments of the present invention, the mapping catheter has a curved section that achieves 180-degree bending deformation.

[0023] In some embodiments of the present invention, the movement of the mapping catheter includes: advancing, retracting, bending, and rotating.

[0024] According to some embodiments of the present invention, the controller is provided with a one-button automatic calibration button for switching between automatic calibration and manual calibration.

[0025] According to an embodiment of the present invention, a three-dimensional modeling method based on force detection feedback is used to perform three-dimensional modeling using the force detection feedback-based three-dimensional modeling system described above. The method includes:

[0026] A10, inputs control commands to the host system via the controller;

[0027] A20, the host system issues a control force sensing actuator execution command according to the control command;

[0028] A30, the current adaptive control module in the force-sensing actuator arm adjusts the input current of the motor power module in real time according to the execution command;

[0029] A40, the measurement module acquires the operating parameters of the motor power module and feeds them back to the host system;

[0030] A50, the host system compares the operating parameters with the corresponding calibration matrix to obtain the contact force corresponding to the operating parameters, and displays it on the display interface;

[0031] A60, based on the displayed contact force, determine the next operation, return to step A10, until the 3D modeling of the object to be tested is completed.

[0032] According to the force-feedback-based 3D modeling method of this invention, without altering the existing high-density mapping catheter device, the force on the tip of the mapping catheter is inferred by monitoring the operating parameters of the force-sensing actuator motor power module. This method is accurate and has a fast response time. It does not require changes to the mapping catheter structure or the addition of extra force sensors, providing a precise, convenient, and low-cost method for detecting force on the tip of interventional devices. The entire process, monitored by the catheter tip force detection system, is both safe and efficient, shortening the overall time of electrophysiological surgery, reducing its complexity, and shortening the operator training period.

[0033] According to an embodiment of the present invention, a three-dimensional modeling method based on force detection feedback is used to perform three-dimensional modeling using the force detection feedback-based three-dimensional modeling system described above. The method includes:

[0034] B10, the host system issues the execution command to control the force-sensing actuator;

[0035] B20, the current adaptive control module in the force-sensing actuator arm adjusts the input current of the motor power module in real time according to the execution command;

[0036] B30, the measurement module acquires the operating parameters of the motor power module and feeds them back to the host system;

[0037] B40, the host system compares the operating parameters with the corresponding calibration matrix to obtain the contact force corresponding to the operating parameters;

[0038] B50, the main control system determines whether the calibration conduit is against the inner wall of the object to be measured based on the contact force, and reaches the contact force required for three-dimensional calibration. When the contact force is reached, the signal acquisition of the corresponding area is completed, and a three-dimensional local model of the corresponding area is formed.

[0039] B60, the main control system issues an execution command to retract the control force sensing arm to drive the mapping catheter to retract. After receiving data that the contact force at the catheter tip is zero, the main control system controls the mapping catheter to move to the unmarked area to perform three-dimensional modeling until the three-dimensional modeling of the object to be measured is completed.

[0040] According to the force detection feedback-based three-dimensional modeling method of the present invention, fully automated three-dimensional modeling of the heart cavity is realized, which replicates the force feedback judgment process of the human hand, greatly improves the consistency and reliability of surgical efficiency, and shortens the learning curve for doctors. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall structure of a force detection feedback-based 3D modeling system according to an embodiment of the present invention.

[0042] Figure 2 This is a flowchart illustrating the operation of a pressure monitoring system according to an embodiment of the present invention.

[0043] Figure 3 This is a schematic diagram of the automatic 3D modeling process according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the operation of the mapping catheter in the left atrium according to an embodiment of the present invention.

[0045] Figure label:

[0046] Force-sensing actuator 1, workstation computer 2, main control system software 3, controller 4, three-dimensional mapping system 5, magnetic positioning sensor 10, ring-shaped electric positioning sensor 20, bend 30, rigid tube 40, puncture position 50, left atrial cavity 60, boundary pressure sensing area 70. Detailed Implementation

[0047] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0048] The steps described in the specification and the flowcharts in the accompanying drawings of this invention are not necessarily to be strictly followed according to the step numbers; the execution order of the steps can be changed. Furthermore, certain steps can be omitted, multiple steps can be combined into one step, and / or one step can be broken down into multiple steps.

[0049] like Figure 1 As shown, the force-sensing feedback-based three-dimensional modeling system according to an embodiment of the present invention includes: a mapping guide tube, a three-dimensional mapping system 5, a force-sensing actuator 1, a controller 4, and a workstation computer 2.

[0050] Among them, the three-dimensional mapping system 5 is connected to the mapping conduit and is used to perform three-dimensional modeling of the object under test based on the measurement information of the mapping conduit;

[0051] The calibration guide is adapted to be fixed to the force-sensing actuator 1 so that the force-sensing actuator 1 drives the movement of the calibration guide; the force-sensing actuator 1 has a motor power module and a measurement module, the measurement module is used to measure the operating parameters of the motor power module;

[0052] The controller 4 is used to input control commands to control the movement of the mapping catheter;

[0053] The workstation computer 2 is connected to both the force-sensing actuator 1 and the controller 4. The workstation computer 2 receives control commands to control the force-sensing actuator 1 to drive the measurement guide to move.

[0054] The main control system software 3 is installed on the workstation computer 2 and stores a calibration matrix. The calibration matrix records the correspondence between the contact force of the calibration guide tube and the operating parameters.

[0055] During the 3D modeling process, workstation computer 2 receives the operating parameters measured by the measurement module and obtains the contact force of the calibration catheter by querying and comparing the calibration matrix.

[0056] According to the force detection feedback-based three-dimensional modeling system of the present invention, there is no need to integrate expensive force sensors at the tip of the mapping catheter. Force detection can be achieved using existing high-density mapping catheters, which significantly reduces costs and system complexity. The present invention infers the force at the tip of the catheter by monitoring the operating parameters of the motor power module of the force sensing actuator 1. The method is accurate and has a fast response speed.

[0057] According to some embodiments of the present invention, the operating parameters include input current and output torque. The measurement module is used to measure the input current and / or output torque of the motor power module. The calibration matrix records the correspondence between the contact force of the calibration conduit and the input current and / or output torque. During the three-dimensional modeling process, the workstation computer 2 obtains the contact force of the calibration conduit by querying and comparing the calibration matrix based on the received input current and / or output torque.

[0058] In other words, the correspondence between the input current and the contact force of the calibration catheter can be established through the calibration matrix, the correspondence between the output matrix and the contact force of the calibration catheter can be established through the calibration matrix, and the correspondence between the contact force of the calibration catheter and the input current and the output matrix can also be established through the calibration matrix.

[0059] In some embodiments of the present invention, the calibration matrix includes: records of the correspondence between the contact force and operating parameters of the calibration catheter in a static state, and the correspondence between the contact force and operating parameters of the calibration catheter in a moving state. It should be noted that the calibration matrix is ​​established in different states, which improves the accuracy of force detection.

[0060] According to some embodiments of the present invention, the force-sensing actuator 1 further includes a current adaptive control module, connected to the main control computer, for adaptively adjusting the input current of the motor power module according to the control commands of the controller 4. This improves the accuracy and intelligence of the force-sensing actuator 1 control, enabling rapid response to changes and maintaining the stability of the controlled external force.

[0061] In some embodiments of the present invention, the mapping duct is equipped with a three-dimensional magnetic positioning sensor and a ring electrode electrical positioning sensor to collect spatial coordinate information and feed it back to the three-dimensional mapping system 5 for three-dimensional modeling.

[0062] According to some embodiments of the present invention, the mapping catheter has a curved section that can bend 180 degrees. This allows for flexible control of the mapping catheter, facilitating measurements at different locations.

[0063] In some embodiments of the present invention, the movement of the mapping catheter includes: forward movement, retraction, bending, and rotation. This allows for flexible control of the mapping catheter.

[0064] According to some embodiments of the present invention, the controller 4 is provided with a one-button automatic mapping button for switching between automatic and manual mapping. It should be noted that the 3D modeling system of the present invention supports one-button switching between automatic and manual modes, ensuring both the efficiency of automated modeling and providing the surgeon with the flexibility to manually intervene in key areas.

[0065] According to an embodiment of the present invention, a three-dimensional modeling method based on force detection feedback is used to perform three-dimensional modeling using the above-mentioned three-dimensional modeling system based on force detection feedback. The method includes:

[0066] A10, inputs control commands to the host system via the controller;

[0067] A20, the host system issues control force sensing actuator commands based on control instructions;

[0068] A30, the current adaptive control module in the force-sensing actuator arm adjusts the input current of the motor power module in real time according to the execution command;

[0069] A40, the measurement module acquires the operating parameters of the motor power module and feeds them back to the host system;

[0070] In the A50 system, the host system compares the operating parameters with the corresponding calibration matrix to obtain the contact force corresponding to the operating parameters, and displays it on the display interface.

[0071] A60, based on the displayed contact force, determine the next operation, return to step A10, until the 3D modeling of the object to be tested is completed.

[0072] According to the force-feedback-based 3D modeling method of this invention, without altering the existing high-density mapping catheter device, the force on the tip of the mapping catheter is inferred by monitoring the operating parameters of the force-sensing actuator motor power module. This method is accurate and has a fast response time. It does not require changes to the mapping catheter structure or the addition of extra force sensors, providing a precise, convenient, and low-cost method for detecting force on the tip of interventional devices. The entire process, monitored by the catheter tip force detection system, is both safe and efficient, shortening the overall time of electrophysiological surgery, reducing its complexity, and shortening the operator training period.

[0073] According to an embodiment of the present invention, a three-dimensional modeling method based on force detection feedback is used to perform three-dimensional modeling using the above-mentioned three-dimensional modeling system based on force detection feedback. The method includes:

[0074] B10, the host system issues the execution command to control the force-sensing actuator;

[0075] B20, the current adaptive control module in the force-sensing actuator arm adjusts the input current of the motor power module in real time according to the execution command;

[0076] B30, the measurement module acquires the operating parameters of the motor power module and feeds them back to the host system;

[0077] B40, the host system compares the operating parameters with the corresponding calibration matrix to obtain the contact force corresponding to the operating parameters;

[0078] B50, the main control system determines whether the calibration guide is against the inner wall of the object to be measured based on the contact force, and reaches the contact force required for three-dimensional calibration. When the contact force is reached, the signal acquisition of the corresponding area is completed, and a three-dimensional local model of the corresponding area is formed.

[0079] B60, the main control system software sends an execution command to retract the control force sensing actuator arm to drive the mapping catheter to retract. After receiving data that the contact force at the catheter tip is zero, the main control system controls the mapping catheter to move to the unmarked area to perform 3D modeling, until the 3D modeling of the object to be measured is completed.

[0080] According to the force detection feedback-based three-dimensional modeling method of the present invention, fully automated three-dimensional modeling of the heart cavity is realized, which replicates the force feedback judgment process of the human hand, greatly improves the consistency and reliability of surgical efficiency, and shortens the learning curve for doctors.

[0081] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should be understood that the following description is merely exemplary and should not be construed as a specific limitation of the present invention.

[0082] like Figure 1 As shown, the force-sensing feedback-based 3D modeling system of the present invention includes: a force-sensing actuator 1, a workstation computer 2 and a main control system software 3, a controller 4, and a 3D mapping system 5.

[0083] The working principle of this invention is to control multiple degrees of freedom of the high-density mapping catheter through the force-sensing actuator 1, and to complete the three-dimensional modeling of the heart chamber by applying a multi-dimensional spatial control algorithm. During the modeling process, the contact force between the catheter tip and the heart chamber is accurately detected and fed back to the workstation host to complete the detection of the three-dimensional boundary of the heart chamber. This solves the problem that doctors need manual force feedback to complete the three-dimensional modeling. Without relying on catheter electrophysiological signal sensing, the robotic arm can automatically perform three-dimensional modeling in cardiac interventional catheter ablation surgery, which greatly improves efficiency and accuracy.

[0084] 1. Force-sensing actuator arm 1: Used to control interventional instruments to perform specified interventional surgical actions (including axial advance, retreat, rotation and bending), and consists of a motor power module, a current adaptive control module and a measurement module.

[0085] The motor power module drives the robotic arm through a combination of multiple servo motors, providing power output to drive the interventional instrument, namely the high-density mapping catheter, and controlling each degree of freedom. The current adaptive control module is used to adaptively adjust the magnitude of the motor current according to the input commands from the controller 4. The measurement module is used to monitor the input current and output torque of the motor to estimate the force on the tip of the interventional instrument. The input current and output torque are monitored in two states: 1) the current and torque when the interventional instrument is stationary, and 2) the input current and output torque of the corresponding motors during the forward advancement, circumferential rotation, and bending of the interventional instrument.

[0086] The current adaptive control module adaptively adjusts the motor input current based on changes in the control commands received by the robotic arm to ensure that the robotic arm complies with the control commands sent by the main control system. The current adaptive control module employs a self-tuning / parameter adaptive control method. Its principle is to transform the problem involving the controller 4 into a parameter estimation problem, estimating the unknown or time-varying parameters of the controlled object online in real time. These estimates are then substituted into a model-based control design algorithm (such as minimum variance control) to calculate or update the parameters of the controller 4 online. The parameter estimator uses a recursive algorithm to estimate the system model parameters online, employing a Kalman filter for joint state and parameter estimation.

[0087] 2. Workstation computer 2: Connects force-sensing actuator 1 and controller 4. The operating doctor sends various control commands to the workstation host through controller 4, which are converted into execution protocols and sent to force-sensing actuator 1.

[0088] 3. The main control system software 3 stores a calibration matrix showing the correspondence between the contact force of the interventional device tip and the input current and output torque of the motor power module. It receives data from the measurement module and automatically compares it with the calibration matrix to determine the closest set of data. The contact force of the interventional device tip corresponding to this set of data is the force value of the interventional device tip in this state. Finally, this value is fed back to the main control system and displayed on the main control display interface. The operator uses this value and combines it with fluoroscopic images to judge the contact between the interventional device tip and the intracardiac wall tissue. The operator can manually input the next action command or choose automatic modeling. When the main control system software 3 receives the signal of contact between the interventional device tip and the intracardiac wall, it determines that the ECG signal and position information of this part have been collected. The main control system automatically generates the next control command to move the mapping catheter tip to the adjacent intracardiac wall tissue to perform mapping of the next area. This cycle continues until the three-dimensional mapping of the entire intracardiac cavity is completed, and the entire model forms a closed loop, which means that the automatic three-dimensional modeling of the intracardiac cavity is completed.

[0089] 4. Controller 4: As a doctor's control platform, it issues various catheter degree of freedom control commands, and sets the stroke, movement speed, etc. of the drive robotic arm motor assembly.

[0090] 5. Three-dimensional mapping system 5: This system integrates the three-dimensional spatial location information and electrical activity acquired from the tip of the mapping catheter to create an image, providing doctors with a three-dimensional map of cardiac electrical activity. The three-dimensional mapping system 5 is directly connected to the mapping catheter. The mapping catheter has built-in magnetic / electric sensors to complete spatial positioning and data acquisition. The three-dimensional mapping system 5 performs three-dimensional modeling processing. The three-dimensional mapping system 5 includes a computer system host responsible for receiving and analyzing electrical signals and positioning data to generate an electroanatomical model. It also includes a display workstation with a high-resolution screen that displays the three-dimensional cardiac model, electrical activity thermogram (such as activation sequence and voltage distribution), and catheter position in real time.

[0091] Working principle of force detection system:

[0092] 1. The principle of force detection at the catheter tip when the force-sensing actuator 1 controls the catheter in both the stopped and uniform motion states;

[0093] When the force-sensing actuator 1 controls the interventional device to remain in a stopped state (during the period between the end of the previous command and the start of the next command), the corresponding motor remains locked. The locked state is achieved by inputting a low voltage into the motor coil to generate a specific magnetic field to maintain the locked state. Under a fixed voltage, the magnitude of the motor's magnetomotive force is determined by the current passing through the stator. When the interventional device is stopped and the push-back force on its head is large, the push-back force causes a slight retraction tendency of the interventional device and a slight rotation tendency of the motor rotor. The current adaptive control module in the motor detects the slight rotation of the motor rotor and determines that the motor needs a larger magnetomotive force to maintain the locked state. The current adaptive control module then autonomously increases the input current to the motor until the interventional device head achieves force balance. The current adaptive control module detects that the motor rotor does not have a rotation tendency. In this state, the motor input current measured by the measurement module is compared with the calibration matrix in the main control system. The contact force value of the set of data closest to this value is the force value on the interventional device head in this state.

[0094] The force value is fed back to the main control system software 3. After the main control system software 3 recognizes that the force value meets the modeling requirements, it determines that the local modeling of the area has been completed, and automatically inputs the next step of the robotic arm control command to control the tip of the mapping catheter to move to the adjacent cardiac chamber tissue for the next step of mapping. This completes the automatic three-dimensional mapping process. The next control command is generally issued based on the execution status of the previous command. First, the mapping catheter is controlled to retract the previous two control commands (retracting the mapping catheter to the initial position), and then a new control command is re-entered. The new control command is superimposed on the previous historical command to control the tip of the mapping catheter to move to the adjacent tissue, gradually completing the automatic modeling of the entire cardiac chamber. The contact force value is also displayed in the main control interface to prompt the operator on the contact force value of the interventional instrument tip, so that the operator can better judge the contact status of the catheter tip and monitor it in real time. In the manual operation mode of the robotic arm, it can also control the contact between the tip of the mapping catheter and the cardiac tissue more efficiently.

[0095] 2. Force detection at the catheter tip under the condition of uniform speed movement controlled by force sensing actuator 1;

[0096] When the force-sensing actuator 1 controls the interventional instrument to advance forward at a constant speed, the current has a linear relationship with the resistance experienced by the tip of the interventional instrument. The calculated relationship is shown below:

[0097] W=P x T ①;

[0098] P=U x I ②;

[0099] Substituting equation ② into equation ①, we get:

[0100] W=U x I x T ③;

[0101] According to the formula W=F x S ④;

[0102] Equation ③ can be derived from equation ④:

[0103] F x S=U x I x T ⑤;

[0104] From the above formula, we can obtain:

[0105] F = U x I x T / S ⑥;

[0106] In the above formula, W represents the work done; P represents the power; T represents the time; U represents the voltage; I represents the current; F represents the motor output force; and S represents the distance traveled.

[0107] That is, the current I and the resistance F are positively linearly related under ideal conditions, and the force F is proportional to I during uniform motion.

[0108] When the surgical robot controls the interventional instrument to move at a constant speed, the input stator current of the motor has a positive linear relationship with the resistance experienced by the interventional instrument. Based on the magnitude of the resistance experienced by the interventional instrument, the motor current adaptive control module automatically adjusts the input stator current of the motor to increase the output torque of the motor until the current adaptive control module detects that the motor rotor is in a constant speed rotation balance state. The above process is very short (about one pulse). By monitoring the stator current of the motor under the constant speed rotation state of the rotor, the force experienced by the interventional instrument as a whole can be estimated.

[0109] This method allows operators to better assess the resistance generated during the axial advancement of the interventional device within the blood vessel. The main control system automatically compares the input motor current with the calibration matrix stored in the main control system. The force value in the set of data with the closest current value in the calibration matrix is ​​the estimated force during the uniform motion of the interventional device. Finally, the main control system software 3 stores this force value in the internal memory and transmits it to the main control interface for display. The resistance during the motion is much smaller than the resistance force when the proximal end of the mapping catheter contacts the inner wall of the heart chamber to collect signals.

[0110] 3. Methods for obtaining the calibration matrix;

[0111] The calibration matrix is ​​also divided into a calibration matrix list in a static state and a calibration matrix list under the condition of controlling the interventional instrument to move at a constant speed. These are used to compare the current values ​​in the two situations to determine the accurate force value. The two calibration matrices are obtained before the operation in the following ways.

[0112] (1) Calibration matrix in static state: When the interventional device is locked by the robotic arm, a force is applied in the axial direction of the head end of the interventional device and the magnitude of the force is gradually increased. Under different force conditions, the current adaptive control module will adaptively adjust and increase the motor current to execute the locking command input by the main control system in order to keep the interventional device controlled by the robotic arm in a static state. At the same time, the input current value when different forces are applied is recorded, thereby obtaining the calibration matrix of the current value with respect to the magnitude of the force on the head end of the interventional device.

[0113] (2) Calibration matrix under uniform motion state. Similarly, during the process of the robotic arm controlling the interventional device to move forward or backward at a uniform speed, a certain reverse force is applied to hinder its movement. The reverse force is gradually increased until the motor loses its propulsion ability and the interventional device changes from uniform motion to a stationary state. During the process of increasing the reverse force, the magnitude of the current entering the motor is recorded at the same time. Thus, the calibration matrix of the resistance of the interventional device and the motor current value during the uniform motion of the interventional device is obtained.

[0114] During the procedure, the main control system compares the current input to the motor when the interventional instrument is stopped with the calibration matrix in the stationary state. It automatically matches the set of matrix data that is closest to the input current. The force value displayed in this set of data is the force value at the tip of the interventional instrument in that state. This invention determines the force and contact conditions at the tip of the interventional instrument. The robot's main control system then judges the force and contact conditions at the tip of the interventional instrument and controls the robot to perform the next surgical action based on this information.

[0115] 4. Torque is used to determine the contact state;

[0116] This invention also includes a torque measurement module, which estimates the force on the axially moving tip of the interventional device controlled by the motor by measuring the torque on the motor output shaft when the interventional device is in a stopped state (i.e., when the motor is locked). The rotation of the motor output shaft provides power for the axial movement of the interventional device through a series of torque transmission structures. When the tip of the interventional device encounters resistance, the motor outputs a force to control the interventional device to move in the opposite direction to the resistance in order to maintain the interventional device at rest, thus achieving a balance. The force on the tip of the interventional device at this time is determined by measuring the magnitude of the torque. The main control system software 3 stores the measured torque value in the main control system and automatically compares the torque value with the torque calibration matrix of the force value of the interventional device tip. The force value displayed in the set of data that is closest to the measured torque value is the force value of the interventional device tip in this state. This data is recorded and displayed in the main control interface.

[0117] Working process of the automatic force detection 3D modeling device:

[0118] The workflow of the pressure monitoring system is as follows: Figure 2As shown, the system is divided into a doctor control end and a patient end. The doctor control end includes a main interface display, a controller 4, and a host system. The controller 4 is equipped with a one-button automatic mapping button, used to switch between automatic robot mapping and manual operation of the robotic arm mapping by the surgeon. The patient end includes a robotic arm assembly. The force-sensing actuator 1 controls the interventional instrument to enter the patient's body for surgery. The main control system issues control commands to the robotic arm assembly. The current adaptive control module in the robotic arm assembly inputs current to the motor according to the control commands. According to the operation of the motor rotor, the current adaptive control module adaptively adjusts the current value to achieve the control commands of the main control system. The current measurement module and torque measurement module compare the measured real-time current and torque with the corresponding calibration matrix to obtain the set of contact force values ​​that are closest to the corresponding current and torque. This force value is fed back to the main control system. The main control system evaluates the contact of the 3D mapping catheter tip based on the force value, determines whether the catheter is in contact with the heart cavity, determines the boundary of the 3D model, and outputs the next control command to achieve automatic 3D mapping. Simultaneously, this force value is displayed on the main interface, providing the operator with information on the force applied to the catheter tip during mapping, facilitating the operator's monitoring of the safety and effectiveness of the entire mapping process. The following are the specific steps for the operator to manually control the robot for 3D mapping:

[0119] 1. The operator inputs control commands to the host system via the controller;

[0120] 2. The robotic arm executes commands under the control of the host system;

[0121] 3. The current adaptive control module inside the robotic arm inputs current to the motor according to the instructions, and the input current is adjusted in real time by the current adaptive control module according to the control instructions;

[0122] 4. Obtain the current and torque values ​​inside the motor through the current measurement module and torque measurement module, respectively;

[0123] 5. Feedback the acquired current and torque values ​​to the host system;

[0124] 6. The host system compares the data with the corresponding calibration matrix table according to the sent instructions;

[0125] 7. Obtain a set of matrix data that is closest to the acquired current and torque values. The force value corresponding to this set of matrix data is the force value of the interventional device catheter.

[0126] 8. Display the obtained force values ​​on the main interface of the doctor's control panel;

[0127] 9. The doctor determines the next step based on the force value displayed on the main interface of the control terminal;

[0128] 10. Return to step one and input the next operation instructions into the host system through the controller. The system will execute the above process until the surgery is over.

[0129] Automated 3D Modeling Process Figure 3 As shown, the pressure monitoring system first outputs a pressure value to the main control system. The main control system then determines the contact status of the catheter tip based on the pressure value. If the pressure value reaches the set value, it indicates that the catheter tip has abutted against the inner wall of the heart chamber and reached the contact force required for three-dimensional mapping. This completes the signal acquisition for that area and forms a three-dimensional local model of that area. The navigation system within the main control system then controls the catheter to retract and bend (executing control commands opposite to the previous two dimensions), i.e., retracting it to the initial position where it is not in contact with the inner wall of the heart chamber, with the contact pressure value of the catheter tip being zero. After receiving the data that the contact pressure value of the catheter tip is zero, the main control system controls the three-dimensional mapping catheter to execute a combination of bending / rotating / forward commands, controlling the catheter tip to move to the edge of the three-dimensional local model completed in the previous step, gradually completing the three-dimensional modeling of the entire heart chamber. The combined commands are generated by the navigation system algorithm, combined with the already completed partial three-dimensional model, to achieve automatic positioning of the catheter tip.

[0130] 3D modeling of the heart chambers and path planning for movement, including manipulation within the left atrium. Figure 4 As shown.

[0131] Among them, the mapping catheter has a built-in magnetic positioning sensor 10, a ring-shaped electrical positioning sensor 20, a bent portion of the mapping catheter 30, a rigid tube body of the mapping catheter 40, an atrial septum puncture site from the right atrium to the left atrium 50, a left atrial cavity 60, and a boundary pressure sensing area 70.

[0132] The force-sensing actuator 1 controls the axial forward and backward movement, axial rotation, and bending of the mapping catheter to move the catheter within the heart chamber. Figure 4 To model the catheter in the left atrium and plan the system for 3D mapping for atrial fibrillation ablation, the left atrium is first accessed via atrial septal puncture. The atrial septal puncture site serves as the fixed position for the catheter, and the mapping catheter has a rigid body. Automated 3D modeling is performed using the atrial septal puncture point as the fulcrum.

[0133] The mapping guide tube has a built-in three-dimensional magnetic positioning sensor and a ring electrode electrical positioning sensor to collect spatial coordinate information and feed it back to the three-dimensional mapping system 5 to complete the modeling.

[0134] The curved section of the mapping catheter is used to cover the entire heart chamber. It can be bent 180 degrees at the tip and rotated to complete the coverage of the entire heart chamber.

[0135] When the catheter moves within the blood pool of the heart chamber, the pressure is 0 when it is not close to the inner wall of the heart chamber. When it approaches the inner wall of the heart chamber, the pressure rises significantly, allowing the system control software to sense the contact between the catheter and the inner wall of the heart chamber, thereby completing the detection of the three-dimensional boundary of the heart chamber.

[0136] During automatic 3D modeling, the catheter bend starts from 0 degrees and is rotated 360 degrees circumferentially to complete the modeling of the local area. Then, the doctor manipulates the device 4 to increase the bend by 5 to 10 degrees and rotate it 360 degrees circumferentially again to complete the modeling of the local area, until the bend is increased to 180 degrees to complete the 3D modeling of the area around the atrial septum.

[0137] The following are the specific steps and procedures for automatic modeling:

[0138] 1. The pressure monitoring system outputs the pressure value at the tip of the calibration catheter in real time to the main control system software.

[0139] 2. If the pressure value does not reach the set value, it will indicate that the tip of the mapping catheter has not contacted the inner wall of the heart chamber, and control the mapping catheter to continue moving forward until the pressure monitoring system reports that the pressure value has reached the set value, and then stop the catheter movement;

[0140] 3. Acquire electrical signals from the cardiac chamber wall using the electrode at the tip of the three-dimensional mapping catheter;

[0141] 4. The modeling system generates a 3D model of the area in real time and outputs the model to the main control system in real time;

[0142] 5. The navigation system controls the retraction and loosening of the mapping catheter, returning it to its initial position until the catheter tip is no longer in contact;

[0143] 6. The navigation system generates new catheter control commands based on the 3D model and the historical modeling input of the mapping catheter control commands, and controls the tip of the 3D mapping catheter to the unfinished modeling area at the edge of the 3D model;

[0144] 7. After executing a new catheter control command, if the pressure value at the catheter tip has not yet reached the set value, continue to input the forward command until the pressure value at the catheter tip reaches the set value. Then stop the forward command and proceed with steps 3-7. If the pressure value at the catheter tip reaches the set value ahead of schedule during the execution of a new catheter control command, the control commands that have not yet been executed will be stopped automatically, and then proceed with steps 3-7.

[0145] 8. Continue until the 3D model is closed, completing the 3D modeling and mapping of all parts of the heart chamber, and realizing the automatic 3D modeling of the heart by the surgical robot.

[0146] In summary, this invention, without altering existing high-density mapping catheter devices, achieves fully automated three-dimensional intracardiac modeling through a force detection system. Force detection at the tip of ordinary clinically used three-dimensional mapping catheters can be achieved without changing the catheter structure or adding additional force sensors. This provides a precise, convenient, and low-cost force detection system for the interventional device tip. Intraoperative automatic modeling can be initiated with a single button, requiring only external monitoring by the surgeon. The surgical robot can quickly and automatically complete the entire three-dimensional cardiac mapping process. The entire process, monitored by the catheter tip force detection system, is both safe and efficient, shortening the overall time of electrophysiological surgery, reducing its complexity, and shortening the surgeon training period.

[0147] Through the description of specific embodiments, a more in-depth and specific understanding should be gained of the technical means and effects adopted by the present invention to achieve the intended purpose. However, the accompanying drawings are only provided for reference and illustration and are not intended to limit the present invention.

Claims

1. A three-dimensional modeling system based on force detection feedback, characterized in that, include: Mapping catheter; A three-dimensional mapping system, which is communicatively connected to the mapping conduit, is used to perform three-dimensional modeling of the object under test based on the measurement information of the mapping conduit; A force-sensing actuator arm, wherein the mapping conduit is adapted to be fixed to the force-sensing actuator arm so that the movement of the mapping conduit is driven by the force-sensing actuator arm; The force-sensing actuator arm has a motor power module and a measurement module, the measurement module being used to measure the operating parameters of the motor power module; The controller is used to input control commands to control the movement of the mapping catheter; The workstation computer is connected to both the force-sensing actuator and the controller. The workstation computer receives the control commands to control the force-sensing actuator to drive the movement of the mapping catheter. The main control system software is installed on the workstation computer and stores a calibration matrix. The calibration matrix records the correspondence between the contact force of the calibration catheter and the operating parameters. During the 3D modeling process, the workstation computer receives the operating parameters measured by the measurement module and obtains the contact force of the calibration catheter by querying and comparing the calibration matrix.

2. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The operating parameters include input current and output torque. The measurement module is used to measure the input current and / or output torque of the motor power module. The calibration matrix records the correspondence between the contact force of the calibration conduit and the input current and / or the output torque. During the 3D modeling process, the workstation computer obtains the contact force of the calibration conduit by querying and comparing the received input current and / or output torque with the calibration matrix.

3. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The calibration matrix includes: a record of the correspondence between the contact force of the mapping catheter in a static state and the operating parameters, and the correspondence between the contact force of the mapping catheter in a moving state and the operating parameters.

4. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The force-sensing actuator also includes a current adaptive control module, which is connected to the workstation computer and is used to adaptively adjust the input current of the motor power module according to the control command of the controller.

5. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The mapping guide tube is equipped with a three-dimensional magnetic positioning sensor and a ring electrode electrical positioning sensor to collect spatial coordinate information and feed it back to the three-dimensional mapping system for three-dimensional modeling.

6. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The mapping catheter has a curved section that allows for 180-degree bending deformation.

7. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The movement of the mapping catheter includes: forward movement, retraction, bending, and rotation.

8. The three-dimensional modeling system based on force detection feedback according to claim 1, characterized in that, The controller is equipped with a one-button automatic calibration button, which is used to switch between automatic calibration and manual calibration.

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