Control method of surgical robot and surgical robot

Abstract

The application relates to the technical field of robot control, and provides a control method of a surgical robot and the surgical robot. The control method comprises the following steps: acquiring a tracking error, acquiring a dynamic characteristic parameter when the tracking error is greater than or equal to a first threshold value and less than a second threshold value, maintaining a master-slave mapping relationship between a master operating arm and a slave operating arm when the dynamic characteristic parameter meets preset requirements, and disconnecting the master-slave mapping relationship between the master operating arm and the slave operating arm when the dynamic characteristic parameter does not meet the preset requirements or when the tracking error is greater than the second threshold value. In this way, the system can be quickly intervened and protected in a dangerous situation, reasonable position deviation generated in the process of normal tissue traction and movement can be allowed, unnecessary interruption caused by normal operation fluctuation can be avoided, the operation efficiency is improved, and the safety and operation continuity in the operation process are considered.

Description

Technical Field

[0001] This application relates to the field of surgical robot control technology, specifically to a control method for a surgical robot and a surgical robot. Background Technology

[0002] With the continuous development of medical devices, computer technology, and control technology, minimally invasive surgery has been increasingly widely used due to its advantages such as smaller surgical trauma, shorter recovery time, and less patient suffering. Minimally invasive surgical robots, with their high dexterity, high control precision, and intuitive surgical images, can avoid operational limitations, such as filtering hand tremors, and are widely applicable to surgical areas such as the abdominal cavity, pelvic cavity, and thoracic cavity.

[0003] Currently, the largest type of minimally invasive surgical robot is the laparoscopic robot, which generally includes a surgeon's console and a patient surgical platform. The surgeon's console has a master control arm for the surgeon to operate on, while the patient surgical platform has multiple slave control arms, each with an endoscope or different surgical instruments attached to it. The master control arm on the surgeon's console collects the surgeon's operating signals, which are processed by the control system to generate control signals for the slave control arms. The slave control arms then control the surgical instruments attached to them to perform surgical operations or for the endoscope to perform image acquisition, thus establishing a master-slave mapping relationship between the master control arm on the surgeon's console and the surgical instruments on the patient surgical platform.

[0004] In theory, during surgical procedures, the error between the desired position sent by the main manipulator and the actual position reached by the manipulator should be zero. However, in actual robotic surgery, due to various factors such as communication delay, mechanical inertia, signal transmission packet loss, servo response time, differences in the overall stiffness of the manipulator, and filtering and smoothing processes, a tracking error inevitably exists between the desired position sent by the main manipulator and the actual position reached by the manipulator.

[0005] To address tracking error safety, existing technologies generally employ a single threshold protection mechanism. Specifically, when the system detects a tracking error exceeding a preset safety threshold, it typically identifies it as an abnormal collision or interference, immediately severing the master-slave mapping and locking the slave manipulator to prevent damage to surrounding tissues. However, in actual surgical procedures, contact between the slave manipulator and tissue is not always caused by accidental collisions. For example, to obtain a good surgical field, surgical instruments are frequently used to pull or push soft tissues. In this case, the instruments experience elastic resistance from the tissue, causing the tracking error to gradually increase. If the system only judges an anomaly based on the error magnitude and forcibly shuts down, it will interrupt the surgeon's normal operation. Conversely, if the threshold is excessively relaxed to maintain operational continuity, it may fail to stop in time in the event of a collision with a sharp, hard object, leading to serious medical accidents. Summary of the Invention

[0006] This application provides a control method and a surgical robot to solve the problem that it is difficult to balance the operational safety and operational continuity of a surgical robot under single threshold control.

[0007] This application provides a control method for a surgical robot. The surgical robot includes a slave manipulator and a master manipulator, wherein the slave manipulator is controlled by the master manipulator. The control method includes: The tracking error between the master and slave manipulators is obtained; when the tracking error is greater than or equal to a first threshold and less than a second threshold, the dynamic characteristic parameters of the master and slave motion are obtained; the dynamic characteristic parameters are used to characterize the instability trend of the master-slave tracking process, and the second threshold is greater than the first threshold. Under the condition that the dynamic characteristic parameters meet the preset requirements, the master-slave mapping relationship between the master arm and the slave arm is maintained; If the dynamic characteristic parameters do not meet the preset requirements, disconnect the master-slave mapping relationship between the master arm and the slave arm. If the tracking error exceeds the second threshold, disconnect the master-slave mapping relationship between the master and slave arms.

[0008] In this way, by tracking errors and using a hierarchical judgment logic based on dynamic characteristic parameters, and by setting a first threshold and a second threshold, erroneous intervention can be avoided when the error is slight (less than the first threshold), while the risk of continuing operation when the error is extreme (greater than the second threshold) can be prevented. Based on the first and second thresholds, risk assessment using dynamic characteristic parameters ensures that the system can quickly intervene and protect in dangerous situations, while also allowing for reasonable positional deviations during normal tissue pulling and pushing processes. This avoids frequent and unnecessary interruptions due to fluctuations in normal operation, thus effectively balancing safety and operational continuity.

[0009] In one implementation, the dynamic feature parameters include: the rate of change of the tracking error; The preset requirement is that the error change rate is less than the preset change rate threshold.

[0010] In this way, by introducing the error change rate as a derived parameter of tracking error, and taking advantage of the characteristics that normal traction and pushing operations show slow changes in tracking error, while accidental collisions show sharp jumps in tracking error, the error change rate can be compared with a preset change rate threshold to accurately distinguish between normal traction and pushing operations and accidental collisions and interference events. This avoids misjudging the doctor's active force application as an accidental event and triggering unnecessary safety responses, thereby reducing the misjudgment rate of normal operations and improving the consistency of operations without lowering safety standards.

[0011] In one implementation, the dynamic characteristic parameters include: the acceleration of the manipulator; The preset requirement is that the acceleration of the operating arm is less than the preset acceleration threshold.

[0012] In this way, by using the movement acceleration of the slave arm as a dynamic feature parameter and using an acceleration less than a preset threshold as a condition for maintaining master-slave mapping, sudden anomalies such as collisions or jitters can be quickly detected, improving the timeliness of safety response.

[0013] In one implementation, if the dynamic feature parameters meet preset requirements, the following is also included: Apply damping torque feedback to the main control arm; And / or, Output prompts, including acoustic and / or visual prompts.

[0014] In this way, through multimodal feedback mechanisms of touch, vision and / or hearing, the continuity of operation is ensured, the safety of operation and the interactive experience are improved, and the technical problem of doctors easily using too much force when there is a lack of force feedback is solved.

[0015] In one implementation, after the step of disconnecting the master-slave mapping relationship between the master and slave manipulators, the method further includes: Output braking command, which is used to control the movement of the manipulator to stop.

[0016] This prevents secondary injuries caused by inertia, ensuring that the operating arm can stop in its current position in time when an accidental collision occurs, avoiding further puncture or tearing of tissues, and solving the technical problem of the operating arm continuing to move due to inertia after a collision, thus aggravating the injury.

[0017] In one implementation, after the step of obtaining the tracking error between the master and slave manipulators, the method further includes: Obtain the actual direction of movement from the end of the manipulator; Obtain the deviation vector between the desired end position of the master arm and the actual end position of the slave arm, where the magnitude of the deviation vector is the tracking error; Determine the angle between the direction of the deviation vector and the actual direction of movement; If the included angle is greater than a preset angle threshold, disconnect the master-slave mapping relationship between the master arm and the slave arm.

[0018] In this way, by introducing the determination of the direction vector, a three-dimensional evaluation system of tracking error amplitude, dynamic characteristic parameters and tracking error direction is constructed, which can improve the accuracy of distinguishing between normal traction operation and lateral collision event as much as possible, and avoid the risk of misjudgment caused by lateral force of the instrument or nonlinear tissue deformation.

[0019] In one implementation, the manipulator arm includes a lens-holding arm for mounting an imaging device and a surgical arm for mounting an end effector. If the dynamic feature parameters meet the preset requirements, it also includes: Obtain the field of view of the imaging device; When the end effector is outside the field of view, control the movement of the lens-holding arm to bring the end effector into the updated field of view.

[0020] In this way, the linkage mechanism between the controlled instrument arm and the lens-holding arm ensures the visibility of the end effector and solves the problem of loss of field of view caused by large-scale movement of the end effector.

[0021] In one implementation, after the step of disconnecting the master-slave mapping relationship between the master and slave manipulators, the method further includes: If it is detected that the slave arm restores the master-slave mapping with the master arm within a preset time and the end effector of the slave arm has not been disassembled, the first threshold, the second threshold and / or the threshold corresponding to the preset requirement are increased.

[0022] In this way, by dynamically adjusting the safety threshold to adapt to the doctor's operating habits, unnecessary downtime in similar operating scenarios can be reduced.

[0023] In one implementation, the control method further includes: identifying an end effector mounted at the end of the manipulator arm; If the end effector is a preset actuator, increase the first threshold, the second threshold, and / or the threshold corresponding to the preset requirement.

[0024] In this way, for preset actuators that are less likely to cause tissue damage, a relatively broad first threshold, second threshold, and / or threshold corresponding to preset requirements can be set, making it easier for doctors to perform operations through preset actuators.

[0025] This application embodiment also provides a surgical robot, including a master manipulator, a slave manipulator, and a controller, wherein the slave manipulator is controlled by the master manipulator. The controller communicates with the master and slave arms and is configured to execute the control method described above.

[0026] This application provides a control method for a surgical robot and a surgical robot. The control method includes: acquiring the tracking error between a master manipulator and a slave manipulator; acquiring dynamic characteristic parameters of the master-slave motion when the tracking error is greater than or equal to a first threshold and less than a second threshold; the dynamic characteristic parameters are used to characterize the instability trend of the master-slave tracking process, and the second threshold is greater than the first threshold; maintaining the master-slave mapping relationship between the master manipulator and the slave manipulator when the dynamic characteristic parameters meet preset requirements; disconnecting the master-slave mapping relationship between the master manipulator and the slave manipulator when the dynamic characteristic parameters do not meet preset requirements; and disconnecting the master-slave mapping relationship between the master manipulator and the slave manipulator when the tracking error is greater than the second threshold.

[0027] In this way, by tracking errors and using a tiered judgment logic based on dynamic characteristic parameters, and by setting a first threshold and a second threshold, we can avoid misintervention when the error is minor (less than the first threshold) and prevent the risk of continuing the operation when the error is extreme (greater than the second threshold). Based on the first and second thresholds, we use dynamic characteristic parameters to determine the risk, ensuring that the system can quickly intervene and protect in dangerous situations, while also allowing for reasonable positional deviations that may occur during normal tissue traction and displacement by the surgeon. This avoids frequent and unnecessary interruptions due to fluctuations in normal operation, thereby improving surgical efficiency and achieving an effective balance between safety and operational continuity. Attached Figure Description

[0028] To more clearly illustrate the implementation methods in the embodiments of this application or related technologies, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0029] Figure 1 This is a schematic diagram of the overall process of a control method for a surgical robot provided in an embodiment of this application.

[0030] Figure 2 This is an overall flowchart of a control method for a surgical robot when the dynamic characteristic parameter is the rate of change of error, provided in an embodiment of this application.

[0031] Figure 3 An extended flowchart of a surgical robot control method based on direction vector determination is provided in an embodiment of this application.

[0032] Figure 4 A flowchart illustrating the linkage control of the endoscope arm in a control method for a surgical robot provided in this application embodiment.

[0033] Figure 5The flowchart illustrates the end effector type identification and threshold adaptive adjustment of a control method for a surgical robot provided in this application embodiment. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of this application.

[0035] It should be noted that many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0036] In this application, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0037] The terms “instrument,” “surgical instrument,” and “surgical device” are used herein to describe medical devices configured for insertion into a patient and for performing surgical or diagnostic procedures, generally including end effectors. End effectors can be surgical tools associated with one or more surgical procedures, such as forceps, needle holders, scissors, bipolar cauterizers, tissue stabilizers or retractors, clamp applicators, anastomosis devices, and the like. The term “imaging device” is used herein to describe imaging devices (e.g., endoscopes or ultrasound probes) configured for insertion into a patient and for performing surgical or diagnostic procedures. Some instruments used in embodiments of this application further provide articulated supports (sometimes referred to as “wrist joints” or “articular seats”) for the surgical tool, allowing the position and / or orientation of the end effector to be flexibly manipulated relative to the instrument axis with one or more mechanical degrees of freedom. Further, many end effectors include functional mechanical degrees of freedom, such as jaws that open or close or blades that translate along a specific path. Instruments may also contain permanent or updatable stored information (e.g., on a PCBA board within the instrument). Accordingly, the system can provide one-way or two-way information communication between the instrument and one or more system components.

[0038] The term "mate" (sometimes referred to as "connection," "link," "installation," or "assembly") can be broadly understood as any situation in which two or more objects are connected in a manner that allows the mating objects to operate in combination with each other. It should be noted that a mating does not require a direct connection (e.g., a direct physical or electrical connection), but rather that many objects or components can be used to mate two or more objects. For example, object A and object B can be mated using object C. Furthermore, the terms "detachably connected" or "detachably mated" can be interpreted as implying a non-permanent connection or mating situation between two or more objects. This means that detachably connected objects can be unconnected and separated, allowing them to operate without being joined.

[0039] Finally, the terms “or” and “and / or” as used herein should be interpreted inclusively, meaning either one or any combination thereof. Therefore, “A, B, or C” or “A, B, and / or C” means any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C. Exceptions to this definition will only occur when the combination of elements, functions, steps, or actions is inherently mutually exclusive in some way.

[0040] In recent years, laparoscopic surgical robots have become an indispensable and highly valuable intelligent tool in minimally invasive surgical practice. Working in tandem with imaging technology, laparoscopic surgical robots provide precise and effective support for complex laparoscopic surgical scenarios such as urinary system tumor resection, gynecological disease treatment, thoracic and abdominal organ surgery, and gastrointestinal interventional procedures, and are widely used in multiple specialties.

[0041] Laparoscopic surgical robots typically consist of a surgeon control platform, a patient operating platform, and an imaging platform. The surgeon sits on the surgeon control platform, viewing two-dimensional or three-dimensional images of the surgical area transmitted by a laparoscope placed inside the patient's body. They also control the movement of the manipulator arm on the patient operating platform, as well as the surgical instruments or laparoscopes attached to that arm. The manipulator arm simulates a human arm, and the surgical instruments simulate a human hand; both provide the surgeon with a range of movements mimicking the human wrist while filtering out hand tremors.

[0042] A patient surgical platform typically includes a chassis, a column, multiple manipulators connected to the column, and one or more surgical instrument manipulators at the end of a support assembly of each manipulator. Surgical instruments and / or endoscopes are detachably coupled to the surgical instrument manipulator. Each surgical instrument manipulator supports one or more surgical instruments and / or endoscopes operating at the surgical site within the patient's body. Various forms of control are possible that allow each surgical instrument manipulator to move with one or more mechanical degrees of freedom (e.g., all six Cartesian degrees of freedom, five or fewer Cartesian degrees of freedom, etc.). Typically, each surgical instrument manipulator is restricted by mechanical or software constraints to rotate the associated surgical instrument about a center of motion on the surgical instrument that remains stationary relative to the patient. This center of motion is typically located where the surgical instrument enters the body wall, and is generally referred to as the "discent point" or "fixed point."

[0043] An imaging platform typically includes video image capture capabilities (commonly an endoscope) and one or more video displays for showing surgical instruments in the captured images. In some laparoscopic surgical robots, optics are included to transmit images from inside the patient's body to one or more imaging sensors at the distal end of the endoscope. These optics are, for example, CCD (Charge-Coupled Device) or CMOS (Complementary Metal-Oxide-Semiconductor) sensors. The video images are then transmitted to the imaging platform's host computer via photoelectric conversion and other steps. Subsequently, image processing is performed, and the processed images are displayed on the video displays for observation by other doctors or assistants.

[0044] A surgeon's control platform typically includes a chassis, foot pedal assembly, stereoscopic monitor, main manipulator, and manual controllers connected to the end of the main manipulator. The surgeon controls the manual controllers and foot pedal assembly to achieve specific movements and / or energy activation of surgical instruments. The surgeon's control platform can be located at a single position within a surgical system composed of laparoscopic surgical robots, or it can be distributed across two or more positions within the system. Remote master / slave operation can be performed according to a preset level of control; for example, one position acts as the master controller for the main surgical operation, and another position acts as the auxiliary controller for an assistant operation. The master controller performs the main surgical operations, while the auxiliary controller performs auxiliary operations such as laparoscopic movement or tissue traction. In some embodiments, the manual controller can be an input device capable of performing one or more manual operations, such as a joystick, exoskeleton glove, power and gravity-compensated manipulator, etc. These input devices acquire the surgeon's operation signals, which are processed by the control system to generate control signals for the manipulator and surgical instrument manipulators. These signals control the remote-controlled motors on the surgical instrument manipulators, which in turn control the final movement of the surgical instruments.

[0045] Generally, the force generated by the remote-controlled motor is transmitted via a drive system to the end effector of the surgical instrument. In some remote surgical embodiments, the input device for controlling the manipulator can be located remotely from the patient, either inside or outside the patient's room, or even in a different city. The input signal from the input device is then transmitted to the control system. Those familiar with remote manipulation, remote control, and telepresence surgery will understand such a system and its components, which will not be elaborated upon here.

[0046] Theoretically, when the master and slave manipulators of a surgical robot are in master-slave control mode, the error between the desired end-effector position sent by the master manipulator and the actual position reached by the slave manipulator is zero. However, in actual surgery, due to various factors such as communication delay, mechanical inertia, signal transmission packet loss, servo response time, differences in the overall stiffness of the manipulators, and filtering and smoothing processes, a difference inevitably exists between the desired end-effector position sent by the master manipulator and the actual position reached by the slave manipulator. In this application, the deviation between the desired end-effector position of the master manipulator and the actual end-effector position of the slave manipulator is defined as "tracking error".

[0047] The various embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this application.

[0048] This application provides a control method and a surgical robot to solve the problem that it is difficult to balance the operational safety and operational continuity of a surgical robot under single threshold control.

[0049] The first aspect of this application provides a control method for a surgical robot, wherein the surgical robot includes a slave manipulator and a master manipulator, and the slave manipulator is controlled by the master manipulator. For example, the surgical robot is a laparoscopic surgical robot, which includes a master manipulator and a slave manipulator controlled by the master manipulator.

[0050] like Figure 1 As shown, the control method for the surgical robot provided in this application includes steps S110 to S150.

[0051] Step S110: Obtain the tracking error between the master arm and the slave arm.

[0052] Specifically, when the surgical robot is in master-slave control mode (the master manipulator controls the movement of the slave manipulator), the desired end position of the master manipulator and the actual end position of the slave manipulator are acquired in real time, and the tracking error between the slave manipulator and the master manipulator is calculated based on the desired end position of the master manipulator and the actual end position of the slave manipulator.

[0053] Tracking error represents the linear distance in space between the desired position of the master manipulator and the actual position of the slave manipulator. For example, the actual end-effector position of the master manipulator is mapped to the slave manipulator coordinate system through forward kinematics, scaling, and coordinate transformation to obtain the desired end-effector position. The actual end-effector position of the slave manipulator in the slave manipulator coordinate system is then obtained. The three-dimensional deviation vector between the desired and actual end-effector positions is calculated, and the magnitude of the three-dimensional deviation vector is obtained to yield the scalar form of the tracking error.

[0054] Step S120: If the tracking error is greater than or equal to the first threshold and less than the second threshold, obtain the dynamic characteristic parameters of the master-slave motion.

[0055] Dynamic feature parameters are used to characterize the instability trend of the master-slave tracking process, and the second threshold is greater than the first threshold.

[0056] The tracking error is compared with a preset first threshold and a second threshold. If the tracking error is less than the first threshold, it indicates that the slave arm can closely follow the movement of the master arm, the movement deviation of the control command is minimal, and it is in an ideal synchronous following state. At this time, the movement of the slave arm is completely controlled and is not significantly affected by abnormal resistance, collisions, or system hysteresis. Therefore, the slave arm is determined to be in a normal following state and no intervention is required. The slave arm responds normally to the operation of the master arm.

[0057] If the tracking error is greater than or equal to the first threshold and less than the second threshold, it is determined that there may be an operational risk from the operating arm, and dynamic feature parameters need to be obtained for further judgment.

[0058] Among them, dynamic feature parameters are used to characterize the instability trend of the master-slave tracking process. Through dynamic feature parameters, the instability trend of the slave operating arm can be further determined. Dynamic feature parameters are used to characterize the tendency of the master-slave system to deviate from the stable operating state at the current moment.

[0059] The dynamic characteristic parameters are obtained by real-time acquisition of motion state data from the master and slave manipulators. This motion state data includes, but is not limited to, signals such as position, velocity, torque, and current. Several intermediate variables reflecting motion smoothness and tracking accuracy are extracted from this motion state data, such as signal fluctuation amplitude, high-frequency component energy, the degree of abrupt changes between adjacent sampling points, and the deviation trend between the signal and the desired trajectory.

[0060] In the master-slave control architecture of surgical robots, instability trend refers to a predictive indicator that during the existence of the master-slave mapping relationship between the master and slave manipulators, due to reasons such as sudden changes in doctor input, resistance or collision encountered by the slave manipulator, mechanical transmission lag, and control loop response disorder, the master-slave tracking process gradually deviates from the normal stable state and evolves into a trend of loss of control, violent shaking, or accidental collision and stagnation.

[0061] To more clearly illustrate the meaning of instability trend, let's take the error change rate of tracking error as an example, a dynamic characteristic parameter. When the tracking error is between the first and second thresholds, the tracking error itself has not yet reached the hard boundary that necessitates immediate disconnection of the master-slave mapping (i.e., the second threshold of tracking error), but the system has already deviated from the ideal following state. At this time, if the error change rate of tracking error remains at a low level, it indicates that the tracking error is increasing slowly, the manipulator is operating under control, and maintains a low instability trend. Conversely, if the error change rate of tracking error reaches or exceeds the preset change rate threshold, it indicates that the end effector has instantly changed from being able to follow the master manipulator to being subject to strong resistance, posing a risk of loss of control due to collision, jamming, or a severe mismatch between control commands and mechanical response. In other words, the surgical robot is considered to have a high instability trend.

[0062] Taking the acceleration of the slave manipulator as a dynamic characteristic parameter as an example, when the tracking error is between the first and second thresholds, the tracking error itself has not yet reached the hard boundary that requires immediate disconnection of the master-slave mapping (i.e., the second threshold of tracking error), but the system has already deviated from the ideal following state. At this time, if the acceleration of the slave manipulator remains at a low level, it indicates that the movement of the slave manipulator is smooth and controllable, the doctor's input is gentle, and the master-slave system is still operating within a controllable and stable range, with a low tendency to become unstable. Conversely, if the acceleration of the slave manipulator reaches or exceeds the preset acceleration threshold, it indicates that the slave manipulator is undergoing a violent acceleration and deceleration process, and there is a risk of loss of control due to excessively fast movement, collision with tissue, or a serious mismatch between control commands and mechanical response, that is, the surgical robot is considered to have a high tendency to become unstable.

[0063] In other words, determining the instability trend essentially involves using dynamic characteristic parameters (the rate of change of the tracking error and / or the acceleration of the slave arm) to proactively assess whether the master-slave system will slip into an uncontrollable state in the near future, within the buffer zone before the tracking error reaches the second threshold. A smaller slave arm acceleration indicates a more moderate current motion and a lower instability trend. Conversely, a larger slave arm acceleration indicates a more drastic change in kinetic energy, a greater instability trend, and a significantly increased probability of accidental collisions or tissue damage. By determining the instability trend, a proactive decision can be made on whether to maintain or disconnect the master-slave mapping before the tracking error truly exceeds the limit, thus achieving a balance between safety and operational continuity.

[0064] Step S130: If the dynamic feature parameters meet the preset requirements, maintain the master-slave mapping relationship between the master arm and the slave arm.

[0065] Specifically, it is determined whether the dynamic feature parameters meet the preset requirements. If the dynamic feature parameters meet the preset requirements, it indicates that the surgical robot has a low instability trend during the master-slave tracking process, the slave manipulator is within the controllable range, the surgical robot maintains the master-slave mapping relationship between the master manipulator and the slave manipulator, and allows the master manipulator to continue to control the slave manipulator.

[0066] Step S140: If the dynamic characteristic parameters do not meet the preset requirements, disconnect the master-slave mapping relationship between the master arm and the slave arm.

[0067] If the dynamic characteristic parameters do not meet the preset requirements, it indicates that the surgical robot has a high tendency to become unstable during the master-slave tracking process. The master-slave mapping relationship between the master manipulator and the slave manipulator is disconnected, and the movement of the slave manipulator is stopped.

[0068] Step S150: If the tracking error is greater than the second threshold, disconnect the master-slave mapping relationship between the master arm and the slave arm.

[0069] In the master-slave control architecture of surgical robots, the second threshold is set as the maximum safety boundary that the system can tolerate. The value of the second threshold is derived based on the safe distance between the surgical instruments and human tissue, the physical limits of the instrument structure, historical surgical data, and clinical safety guidelines. When the tracking error exceeds the second threshold, it means that the deviation between the actual position of the slave manipulator and the expected position of the master manipulator has exceeded the safety redundancy range designed in the system, and the slave and master manipulators have lost synchronization. In this case, directly disconnecting the master-slave mapping relationship between the master and slave manipulators and executing a safety shutdown can stop the slave manipulator from continuing to move with the fastest response speed, avoiding further puncture, compression, or tearing damage to the patient's tissues.

[0070] It should be noted that the robot in this application embodiment has at least one slave manipulator. In the case of multiple slave manipulators, severing the master-slave mapping relationship between the master manipulator and a certain slave manipulator is a control action for a single slave manipulator, not for all slave manipulators.

[0071] In practical applications, after disconnecting the master-slave mapping relationship between the master and slave operating arms, alarm prompts can be sent to doctors through the human-machine interface. For example, the alarm prompts can be sound, visual, or tactile.

[0072] In practical applications, alarm notifications can also include information about the slave operating arm, so that doctors can more easily identify the slave operating arm whose master-slave mapping relationship has been broken.

[0073] The technical solution of this application embodiment, through the hierarchical judgment logic of tracking error and dynamic characteristic parameters, sets a first threshold and a second threshold. This avoids accidental intervention when the error is slight (less than the first threshold) and prevents the risk of continuing to perform the operation when the error is extreme (greater than the second threshold). Based on the first and second thresholds, risk judgment is performed using dynamic characteristic parameters. This ensures that the system can quickly intervene and protect in dangerous situations, while also allowing for reasonable positional deviations that may occur during normal tissue traction and displacement by doctors. This avoids frequent unnecessary interruptions due to fluctuations in normal operation, thereby effectively balancing safety and operational continuity.

[0074] In some embodiments, the dynamic feature parameter includes the rate of change of the tracking error. A preset requirement is that the rate of change of the error is less than a preset rate of change threshold. Figure 2 As shown, when the dynamic characteristic parameter is the rate of change of the tracking error, the control method of the surgical robot includes steps S210 to S240.

[0075] Step S210: Obtain the tracking error between the master arm and the slave arm.

[0076] Step S220: If the tracking error is greater than or equal to the first threshold and less than the second threshold, obtain the error change rate of the tracking error.

[0077] Among them, the tracking error change rate is used to indicate how the tracking error changes over time, reflecting the increment of the tracking error per unit time. It can indicate whether the tracking error is growing slowly or there is a sudden change, and is used to characterize whether the slave arm is unable to follow the master arm command due to external resistance.

[0078] Step S230: If the error change rate is less than a preset change rate threshold, maintain the master-slave mapping relationship between the master arm and the slave arm.

[0079] When a doctor performs a pushing and pulling operation on tissue, the end effector is continuously subjected to the elastic resistance of the human tissue. The greater the displacement of the end effector, the greater the elastic resistance of the human tissue, the more difficult it is for the end effector to move, the tracking error increases slowly, and the rate of change of the tracking error is within a small range.

[0080] In this way, based on the fact that the error change rate is less than the preset change rate threshold, it can be determined that the doctor is performing a normal operation of pushing and pulling tissue, that is, the error change rate meets the preset requirements, and the master-slave mapping relationship between the master arm and the slave arm is maintained.

[0081] Step S240: If the error change rate is greater than or equal to a preset change rate threshold, disconnect the master-slave mapping relationship between the master arm and the slave arm.

[0082] When an accidental collision occurs with human tissue or other equipment, the end effector instantly changes from being able to follow the main control arm to being subjected to strong resistance, causing a surge in tracking error, with the error rate of change in tracking error being within a large range.

[0083] In this way, based on the error change rate being greater than or equal to the preset change rate threshold, it can be determined that the end effector may have experienced an accidental collision. That is, if the error change rate is greater than or equal to the preset change rate threshold, it is determined that the dynamic characteristic parameters do not meet the preset requirements, and the risk of an accidental collision in the slave arm is high, thereby disconnecting the master-slave mapping relationship between the master arm and the slave arm.

[0084] In this embodiment, by introducing the error change rate as a derived parameter of tracking error, and taking advantage of the characteristics that normal push-pull operations show slow changes in tracking error, while accidental collisions show sharp jumps in tracking error, the error change rate is compared with a preset change rate threshold to accurately distinguish between normal traction operations and accidental collision events or interference events. This avoids misjudging the doctor's active force application as an accidental event and triggering unnecessary safety responses, thereby reducing the misjudgment rate of normal operations and improving the consistency of operations without compromising safety standards.

[0085] In some embodiments, the dynamic characteristic parameters may further include: the acceleration of the manipulator. A preset requirement is that the acceleration of the manipulator is less than a preset acceleration threshold.

[0086] Specifically, during the actual control of the robot, when the tracking error between the master and slave manipulators is detected to be greater than or equal to a first threshold and less than a second threshold, the acceleration of the slave manipulator is acquired. The acceleration can be the linear acceleration of the end effector of the slave manipulator or the angular acceleration of a key joint.

[0087] If the acceleration of the manipulator is determined to be less than a preset acceleration threshold, it is determined that the doctor is performing a normal operation. For example, the doctor is performing a normal fine motor operation, and the master-slave motion of the manipulator is in a controllable and stable state, maintaining the master-slave mapping relationship unchanged.

[0088] If the acceleration of the slave manipulator is greater than or equal to a preset acceleration threshold, the dynamic characteristic parameters are determined to be non-compliant, indicating a high risk of accidental collision or abnormal vibration in the slave manipulator. The slave manipulator exhibits a high tendency to become unstable; therefore, the master-slave mapping relationship between the master and slave manipulators should be disconnected to prevent damage to patient tissues or surgical instruments.

[0089] For example, at the instant of an accidental collision, the movement state of the manipulator changes abruptly due to the strong resistance from the external environment at its end. Specifically, the movement speed drops sharply, rapidly falling to near zero. At the same time, the absolute value of the movement acceleration exhibits a large spike pulse, displaying highly dynamic impact characteristics.

[0090] Conversely, when a physician performs normal tissue displacement or traction operations, the manipulator arm primarily overcomes the viscoelastic resistance of the soft tissue. This resistance characteristic determines that the movement of the instrument changes relatively gradually. In this case, the movement speed of the manipulator arm is usually maintained within a non-zero positive range, and the value is relatively stable. Correspondingly, the absolute value of the movement acceleration remains at a low level, exhibiting a controlled, gradual displacement characteristic.

[0091] In this way, by using the movement acceleration of the slave arm as a dynamic feature parameter and using an acceleration less than a preset threshold as a condition for maintaining master-slave mapping, sudden anomalies such as collisions or jitters can be quickly detected, improving the timeliness of safety response.

[0092] To further improve the reliability of the judgment, in some preferred embodiments, a duration condition can be introduced. For example, the dynamic characteristic parameters are determined not to meet the preset requirements and the master-slave mapping relationship is disconnected only when the acceleration of the slave manipulator is greater than or equal to a preset acceleration threshold and lasts for more than a preset duration (e.g., 20 milliseconds). In cases where the acceleration is only a momentary spike (such as sensor noise or a brief touch) greater than or equal to the preset acceleration threshold, the operation of disconnecting the master-slave mapping relationship between the master and slave manipulators is not triggered, thereby avoiding misjudgments that could affect the smoothness of the surgery.

[0093] It should be noted that the error change rate of the tracking error and the acceleration of the manipulator are only two preferred indicators. In some embodiments, the movement speed of the manipulator can be combined with the acceleration to achieve the same or similar purpose.

[0094] Specifically, when the tracking error is between a first threshold and a second threshold, the rate of change of the tracking error, the moving speed from the end of the manipulator, and the acceleration are acquired. Preset thresholds for the rate of change, speed, and acceleration can be used. When the rate of change of the tracking error is greater than or equal to the preset rate of change threshold, the moving speed is lower than the preset speed threshold, and the absolute value of the acceleration is higher than the preset acceleration threshold, the dynamic characteristic parameters are determined not to meet the preset requirements, an accidental collision is identified, and the master-slave mapping relationship between the master and slave manipulators is immediately disconnected. Conversely, if the conditions are not met, it is determined to be a normal push-pull operation, and the master-slave mapping relationship between the master and slave manipulators is maintained.

[0095] In this way, by introducing kinematic parameters (velocity, acceleration) into the dynamic feature parameter determination system, a multi-dimensional fusion determination logic based on tracking error, the rate of change of tracking error, and kinematic response is constructed, thereby improving the judgment accuracy and reducing the risk of misjudgment in high-speed collision scenarios.

[0096] In some embodiments, when the dynamic characteristic parameters meet preset requirements, a force feedback and safety prompt mechanism is added while maintaining the master-slave mapping relationship between the master and slave manipulators.

[0097] For example, when a doctor is determined to be performing a traction operation based on dynamic characteristic parameters, a damping torque feedback is applied to the master manipulator while maintaining the master-slave mapping relationship. For instance, the force feedback device controlling the master manipulator outputs a damping torque, which is generated based on the tracking error. Specifically, the motor controlling the master manipulator outputs a damping torque proportional to the tracking error. This damping torque simulates the resistance felt by the doctor's hand when traction is applied to human tissue, allowing the doctor to perceive the tissue's tension through touch, thereby precisely controlling the traction force and preventing tissue tearing.

[0098] In this way, the tactile feedback mechanism can effectively prevent doctors from applying excessive force when there is a lack of direct force feedback.

[0099] For example, the magnitude of the damping torque can be designed to be positively correlated with the tracking error; for instance, the damping torque can be determined using a linear model. The formula for calculating the damping torque is as follows: .

[0100] in, This is the damping torque applied to the main control arm. The damping coefficient is the preset value. It can be adjusted according to the type of instrument and the stage of surgery. To account for tracking error. For example, when the tracking error is 3cm and the damping coefficient is set to 0.5N·m / cm, the motor controlling the main operating arm outputs a damping torque of 1.5N·m.

[0101] In this way, by establishing a direct proportional relationship between tracking error and tactile resistance, the greater the traction displacement (i.e., the greater the tissue deformation), the greater the resistance felt by the doctor. This aligns with the physical intuition of actual operation and helps improve the doctor's operational safety and consistency.

[0102] In some embodiments, provided that the dynamic characteristic parameters meet preset requirements, while maintaining the master-slave mapping relationship between the master and slave manipulators, prompting information can also be output. This prompting information includes acoustic and / or visual prompts, used to indicate that the slave manipulator is in a high-resistance state. For example, a yellow warning box may pop up on the doctor's console display, or a voice prompt may be played through a speaker, indicating that the slave manipulator is currently in a high-resistance operating environment, or that the doctor is currently in a "tissue traction / pushing" operating mode.

[0103] In this way, through a multimodal feedback mechanism of touch, vision, and hearing, the continuity of operation is ensured, while the safety and interactive experience of operation are improved.

[0104] In some embodiments, if it is determined that the dynamic characteristic parameters do not meet the preset requirements (such as the tracking error change rate being greater than the change rate threshold) or the tracking error exceeds the second threshold, a braking command is also output on the basis of disconnecting the master-slave mapping relationship between the master arm and the slave arm. The braking command is used to control the slave arm to stop moving.

[0105] For example, a braking command is sent to the servo drive unit of the slave arm to control the joint motor of the slave arm to stop outputting torque, and to lock the current position of the slave arm using an electromagnetic brake or a high-impedance control mode.

[0106] This prevents secondary injuries caused by inertia, ensuring that the operating arm can stop in its current position in time when an accidental collision occurs, avoiding further puncture or tearing of tissues, and solving the technical problem of the operating arm continuing to move due to inertia after a collision, thus aggravating the injury.

[0107] In some embodiments, such as Figure 3 As shown, after the step of obtaining the tracking error between the master arm and the slave arm, the control method further includes steps S310 to S340.

[0108] Step S310: Obtain the actual movement direction from the end of the operating arm.

[0109] Obtain the actual velocity vector from the end effector of the manipulator. For example, this is done by reading the encoder data from each joint of the manipulator, converting the joint angular velocities into linear and angular velocity vectors of the end effector in Cartesian space using the Jacobian matrix, and extracting the linear velocity vector to obtain the actual velocity vector. The direction of the actual velocity vector represents the geometric direction of the actual movement of the manipulator; that is, the direction of the actual velocity vector is the actual direction of movement.

[0110] Step S320: Obtain the deviation vector between the desired end position of the master arm and the actual end position of the slave arm, where the magnitude of the deviation vector is the tracking error.

[0111] Obtain the deviation vector. The deviation vector is defined as the vector pointing from the actual end position of the manipulator to the desired end position mapped from the master manipulator; that is, the deviation vector is the vector pointing from the actual end position to the desired end position. The magnitude of the deviation vector is the tracking error. The deviation vector represents the theoretical direction and distance the manipulator needs to move to eliminate the current position deviation.

[0112] Step S330: Determine the angle between the direction of the deviation vector and the actual direction of movement.

[0113] For example, the angle between the deviation vector and the actual velocity vector is calculated using the vector dot product formula, thereby obtaining the angle between the direction of the deviation vector and the actual direction of movement.

[0114] Step S340: If the included angle is greater than a preset angle threshold, disconnect the master-slave mapping relationship between the master operating arm and the slave operating arm.

[0115] Taking a normal tissue traction scenario as an example, the doctor controls the main manipulator to move forward to traction the tissue. The end effector of the manipulator experiences elastic resistance from the traction tissue, which exerts a backward pulling force on the end effector, causing the actual position of the end effector to lag. At this time, the actual movement direction of the end effector from the manipulator should be in the same direction as the deviation direction or the angle between them should be minimal, because the deviation is precisely caused by the elastic resistance of the traction tissue.

[0116] However, if a lateral collision occurs to the slave manipulator or the instrument joint jams, the slave manipulator may be subjected to a lateral force deviating from the direction of movement, resulting in a large angle between the deviation direction and the actual direction of movement. Therefore, the relationship between this angle and a preset angle threshold is determined. If the angle is greater than the preset angle threshold, it is determined that the deviation direction does not conform to the force characteristics of tissue traction, meaning that the current tracking error is not due to positive tissue traction, but rather to lateral interference or abnormal force. Even if the dynamic characteristic parameters (such as the rate of change) meet the preset requirements, the master-slave mapping relationship between the master and slave manipulators is still disconnected, and a safety shutdown is performed. Conversely, if the angle is less than or equal to the angle threshold, the force direction of the slave manipulator is confirmed to be reasonable. If the dynamic characteristic parameters (such as the rate of change) also meet the preset requirements, the current mapping relationship is maintained.

[0117] In this way, by introducing the determination of the direction vector, a three-dimensional evaluation system of tracking error amplitude, dynamic characteristic parameters and tracking error direction is constructed, which can improve the accuracy of judgment of normal traction operation as much as possible and avoid the risk of misjudgment caused by lateral force of the instrument or nonlinear tissue deformation.

[0118] In some embodiments, the manipulator arm includes a lens-holding arm for mounting an imaging device and an instrument arm for mounting an end effector. For example... Figure 4 As shown, when the dynamic characteristic parameters meet the preset requirements, the control method further includes steps S410 to S420.

[0119] Step S410: Obtain the field of view of the imaging device.

[0120] During surgical procedures performed by a surgical robot, the field of view of the imaging device is acquired in real time after it is placed in place. The field of view of the imaging device is determined by its optical parameters (such as viewing angle and focal length) and its current pose, and can be calculated in real time using the intrinsic parameter model and forward kinematics of the imaging device. In practical applications, the end effector of the surgical arm may involve a large range of movement.

[0121] For example, the end effector can significantly remove obstructions covering the field of view. That is, after the end effector engages with the target object, it can move a long distance in a straight line or arc away from the center of the field of view until the object is pushed or pulled beyond the physical boundary of the current image.

[0122] For example, the end effector performs a wide-range planar cleaning motion, that is, controls the end effector to perform a large-amplitude reciprocating scan or fan-shaped oscillation along a fixed plane within the body cavity. During this process, the displacement span of the end effector usually exceeds the diameter range of the endoscope's field of view.

[0123] For example, the tissue tension pulling of the end effector's execution depth means that after the end effector clamps the target, it is dragged continuously over a long distance in a single direction, causing the position of the end effector to shift relative to the initial point.

[0124] For example, the end effector performs a panoramic exploration action, that is, controls the end effector to make large-scale jump movements between multiple different azimuth angles, and successively touches and adjusts the posture of objects in different positions.

[0125] Step S420: When the end effector is outside the field of view, control the movement of the lens holding arm so that the end effector is within the updated field of view.

[0126] The position of the end effector of the instrument arm is monitored in real time to determine whether it is outside the field of view. If the end effector is outside or about to be outside the field of view, the instrument arm is controlled to move along a preset safety trajectory to bring the end effector back into the field of view and as close as possible to the center of the field of view.

[0127] In some cases, the preset trajectory is constrained by historical safe locations, allowing movement only within already traversed safe spaces or adjacent areas to avoid the endoscope colliding with human tissue.

[0128] In some cases, after the operation of a large-scale movement of the end effector is completed, the scope arm is controlled to return to its initial position. Specifically, if the movement trend of the end effector is detected to reverse or stop, and no large-scale movement is initiated again for a preset duration (e.g., 2 seconds), it is determined that the traction operation has been completed, and the scope arm is automatically controlled to smoothly return to its initial pose along a preset safety trajectory.

[0129] Optionally, after the traction operation is completed, a pop-up window with a reset prompt button can be displayed on the human-computer interaction interface. The pop-up window includes two optional buttons: "Reset" and "Keep Current Position." Simultaneously, the reset or hold function pedals on the main operating arm (first designated operation, second designated operation, and foot pedal) are enabled. The doctor can select to adjust the endoscopic field of view back to its initial position by clicking the reset button on the screen, performing the first designated operation, or stepping on the reset function pedal. If the doctor chooses not to reset, they can explicitly express their intention not to reset by clicking the "Keep Current Position" button, performing the second designated operation, or stepping on the hold function pedal. The endoscope arm will then remain in its current position, allowing the doctor to continue operating within the current field of view. If the doctor does not make a selection within a preset time (e.g., 5 seconds), automatic reset will be performed by default. This provides both automated field of view restoration and the doctor's autonomy, balancing operational efficiency and flexibility.

[0130] During the smooth following movement of the end effector along the direction of the control arm, it is necessary to ensure that the end effector remains within the field of view of the imaging screen at all times. In this way, the visibility of the end effector is guaranteed through the linkage mechanism between the controlled instrument arm and the control arm, thus solving the problem of loss of field of view caused by large-scale movement of the end effector.

[0131] The determination of the first threshold, the second threshold, and the threshold corresponding to the preset requirements can be based on empirical values, user-defined values, statistical values ​​based on big data annotations, and the current user's operating habits.

[0132] In some embodiments, the first threshold, the second threshold, and / or the threshold corresponding to the preset requirement can be dynamically adjusted according to the actual application of the surgical robot. For example, after the step of disconnecting the master-slave mapping relationship between the master arm and the slave arm, the control method further includes: if it is detected that the slave arm restores the master-slave mapping with the master arm within a preset time and the end effector of the slave arm has not been disassembled, the first threshold, the second threshold, and / or the threshold corresponding to the preset requirement are increased.

[0133] Specifically, when the dynamic feature parameter is the rate of change of tracking error, the preset threshold is the rate of change threshold. When the dynamic feature parameter is the acceleration of the manipulator, the preset threshold is the acceleration threshold.

[0134] For example, if it is detected that within a preset time (e.g., within 5 seconds) after the master-slave mapping relationship between the master and slave manipulators is disconnected, the doctor quickly restores the master-slave mapping function between the master and slave manipulators by using the clutch reset button on the operation console, and no disassembly or replacement signal of the end effector is detected during this period, then the shutdown is determined to be a false trigger.

[0135] A typical characteristic of accidental triggering is that the doctor actively restores the master-slave mapping and continues to perform the original operation (e.g., continuing to pull tissue), indicating that there was no actual safety risk previously. In this case, the current threshold setting is considered too sensitive, interfering with normal operation. Therefore, an operation to increase the safety threshold is performed, that is, the first threshold, the second threshold, and the dynamic feature parameters are adjusted upwards based on the original values. By increasing the safety threshold, it adapts to the doctor's operating habits, thereby reducing unnecessary downtime in similar operating scenarios.

[0136] For example, if the end effector on the operator arm is detected to be removed or replaced, or if high-frequency operation of the end effector of another operator arm is detected near the contact area, in order to improve operational safety, the first threshold, the second threshold and / or the threshold corresponding to the preset requirement are maintained or lowered.

[0137] After disconnecting the master-slave mapping between the master and slave manipulators, analyze the cause of the shutdown and monitor the physical connection status of the end effector of the slave manipulator. If it is detected that the end effector has been disassembled or detached, or if the identification of the currently installed end effector has been changed (i.e., a new instrument has been replaced), it is determined that the shutdown was most likely caused by a real hard impact, because real impacts often result in damage or contamination of the instrument, requiring disassembly, inspection, or replacement.

[0138] Simultaneously, the motion trajectory data of other slave manipulators were monitored. If it was detected that the end effectors of other slave manipulators were performing high-frequency repetitive operations (such as continuous jogging, cutting, or suturing) near the coordinates of the area where the shutdown had just occurred, it indicated that there might be damaged tissue in that area requiring treatment. This further verified that the break in the master-slave mapping was caused by an accidental collision with the slave manipulator.

[0139] If the system detects that the end effector on the slave arm has been removed or replaced, and high-frequency operation of other end effectors on the slave arm is detected near the contact area, the shutdown is determined to be caused by a real hard collision or high-risk operation. To further improve the safety of subsequent operations, the first threshold, the second threshold, and / or the threshold corresponding to the preset requirements can be maintained or appropriately lowered to enhance the system's sensitivity to minor errors and sudden changes, preventing secondary accidents.

[0140] In some embodiments, such as Figure 5 As shown, the control method further includes steps S510 to S520.

[0141] Step S510: Identify the type identifier of the end effector installed at the end of the manipulator arm.

[0142] Specifically, when a surgical instrument is mounted on the power box interface at the end of the operating arm, the RFID tag or electronic code built into the surgical instrument is read via near-field communication or a physical pin. The tag or electronic code contains the surgical instrument's unique serial number and its end effector type identification information.

[0143] Obtaining the type identifier allows you to determine the type of end effector installed on the manipulator. For example, it can identify that the currently installed end effector is a bipolar duckbill forceps, non-invasive gripper, or retractor with a non-invasive gripping surface, suitable for tissue traction and displacement. Or, it can identify that the currently installed end effector is a single-polar scissors, electric hook, needle holder, or puncture needle with a sharp blade, or an instrument with a sharp structure or used for delicate operations.

[0144] Step S520: If the end effector is a preset actuator, increase the first threshold, the second threshold, and / or the threshold corresponding to the preset requirement.

[0145] Pre-programmed actuators include instruments such as bipolar duckbill forceps, non-invasive grasping forceps, or retractors with non-invasive gripping surfaces, suitable for tissue traction and displacement. These pre-programmed actuators can effectively clamp and pull tissue without causing cutting damage. Physicians are highly likely to use these pre-programmed actuators to perform traction and displacement operations.

[0146] If the end effector is identified as a preset actuator, the appropriate relaxed control parameters are loaded, that is, the values ​​of the first threshold and the second threshold are adjusted accordingly.

[0147] For example, the first threshold can be adjusted from 2cm to 3cm, and the second threshold from 5cm to 7cm. Simultaneously, the preset judgment conditions can be relaxed, such as increasing the threshold corresponding to the preset requirements. By adjusting these safety thresholds, a wider range of tracking errors is allowed during traction, thereby preventing frequent accidental robot shutdowns due to errors when doctors perform normal, large-amplitude tissue exposure movements, ensuring the smoothness of the doctor's operation.

[0148] In this way, for preset actuators that are less likely to cause tissue damage, a relatively broad first threshold, second threshold, and / or threshold corresponding to preset requirements can be set, making it easier for doctors to perform operations through preset actuators.

[0149] In some cases, when the end effector is not identified as a preset actuator, such as when the currently installed instrument is identified as a single-pole scissor with a sharp blade, an electric hook, a needle holder, or a puncture needle, which has a sharp structure or is used for delicate operations, the preset first threshold, second threshold, and judgment threshold of dynamic characteristic parameters are kept unchanged. That is, the default standard safety threshold is adopted to ensure that a high level of safety sensitivity is maintained in delicate cutting or puncture operations, and to prevent the risk of tissue damage from increasing due to the relaxation of thresholds.

[0150] Furthermore, in some preferred embodiments, the instability trend judgment mechanism based on dynamic characteristic parameters is activated only when the end effector is identified as a preset actuator. That is, when the tracking error is between the first threshold and the second threshold, the doctor's operation is further identified as a normal traction operation or an accidental collision event by using dynamic characteristic parameters such as the error change rate or the acceleration of the operating arm.

[0151] For end effectors of other types not belonging to the preset actuators, since these end effectors are not suitable for performing tissue traction or tissue pushing operations, the likelihood of doctors using these end effectors to perform tissue traction or tissue pushing operations is low. Therefore, there is no need to introduce dynamic feature parameters to further determine whether the doctor's operation is a normal tissue traction or tissue pushing operation or an accidental collision event. In this case, once the tracking error is detected to exceed a certain set threshold (which could be a first threshold, a second threshold, or other set values), the master-slave mapping relationship between the master manipulator and the slave manipulator is immediately disconnected.

[0152] This application also provides a surgical robot, including a master manipulator, a slave manipulator, and a controller. The master manipulator is used by the surgeon to input operating commands, and the slave manipulator is used to execute operating actions. Different types of end effectors are adapted to the end of the slave manipulator. The controller is communicatively connected to both the master and slave manipulators. The controller has a built-in processor and memory, and the memory stores a computer program. The processor is configured to execute the control method of the robot described above.

[0153] Specifically, when the processor executes the program, it can calculate the tracking error in real time, call the rate of change calculation module according to the error range, control the output torque of the main manipulator's force feedback motor based on the judgment result, and control the enable state of the slave manipulator's servo motor. Through the combination of hardware and software, the robot achieves intelligent fault-tolerant control of the slave manipulator.

[0154] This application provides a control method for a surgical robot and a surgical robot. The control method includes: acquiring the tracking error between a master manipulator and a slave manipulator; acquiring dynamic characteristic parameters of the master-slave motion when the tracking error is greater than or equal to a first threshold and less than a second threshold; the dynamic characteristic parameters are used to characterize the instability trend of the master-slave tracking process, and the second threshold is greater than the first threshold; maintaining the master-slave mapping relationship between the master manipulator and the slave manipulator when the dynamic characteristic parameters meet preset requirements; disconnecting the master-slave mapping relationship between the master manipulator and the slave manipulator when the dynamic characteristic parameters do not meet preset requirements; and disconnecting the master-slave mapping relationship between the master manipulator and the slave manipulator when the tracking error is greater than the second threshold.

[0155] In this way, by tracking errors and using a tiered judgment logic based on dynamic characteristic parameters, the determination of the first and second thresholds can avoid misintervention in cases of minor errors and prevent the risks associated with continuing operations in cases of extreme errors. Based on the first and second thresholds, risk assessment using dynamic characteristic parameters ensures that the system can quickly intervene and protect in dangerous situations, while also allowing for reasonable positional deviations during normal tissue traction and displacement by doctors. This avoids frequent and unnecessary interruptions due to fluctuations in normal operation, thus effectively balancing safety and operational continuity.

Claims

1. A control method for a surgical robot, the surgical robot comprising a slave manipulator and a master manipulator, the slave manipulator being controlled by the master manipulator, characterized in that, The control method includes: The tracking error between the master arm and the slave arm is obtained; if the tracking error is greater than or equal to a first threshold and less than a second threshold, dynamic characteristic parameters of the master-slave motion are obtained; the dynamic characteristic parameters are used to characterize the instability trend of the master-slave tracking process, and the second threshold is greater than the first threshold. When the dynamic characteristic parameters meet the preset requirements, the master-slave mapping relationship between the master operating arm and the slave operating arm is maintained; If the dynamic characteristic parameters do not meet the preset requirements, the master-slave mapping relationship between the master operating arm and the slave operating arm is disconnected. If the tracking error is greater than the second threshold, the master-slave mapping relationship between the master arm and the slave arm is disconnected.

2. The control method according to claim 1, characterized in that, The dynamic characteristic parameters include: the rate of change of the tracking error; The preset requirement is that the error change rate is less than a preset change rate threshold.

3. The control method according to claim 1, characterized in that, The dynamic characteristic parameters include: the acceleration of the operating arm; The preset requirement is that the acceleration of the slave arm is less than a preset acceleration threshold.

4. The control method according to claim 1, characterized in that, If the dynamic characteristic parameters meet the preset requirements, the method further includes: Apply damping torque feedback to the main operating arm; And / or, Output prompt information, which includes acoustic prompt information and / or visual prompt information.

5. The control method according to any one of claims 1-4, characterized in that, After the step of disconnecting the master-slave mapping relationship between the master operating arm and the slave operating arm, the method further includes: Output a braking command, which is used to control the operation arm to stop moving.

6. The control method according to any one of claims 1-4, characterized in that, After the step of obtaining the tracking error between the master arm and the slave arm, the method further includes: Obtain the actual direction of movement from the end of the operating arm; Obtain the deviation vector between the desired end position of the master arm and the actual end position of the slave arm, wherein the magnitude of the deviation vector is the tracking error; Determine the angle between the direction of the deviation vector and the actual direction of movement; If the included angle is greater than a preset angle threshold, the master-slave mapping relationship between the master operating arm and the slave operating arm is disconnected.

7. The control method according to any one of claims 1-4, characterized in that, The manipulator arm includes a lens-holding arm for mounting imaging equipment and a surgical arm for mounting an end effector. If the dynamic characteristic parameters meet the preset requirements, the method further includes: Obtain the field of view of the imaging device; When the end effector is outside the field of view, the lens-holding arm is controlled to move so that the end effector is within the updated field of view.

8. The control method according to any one of claims 1-4, characterized in that, After the step of disconnecting the master-slave mapping relationship between the master operating arm and the slave operating arm, the method further includes: If it is detected that the slave manipulator restores the master-slave mapping with the master manipulator within a preset time and the end effector of the slave manipulator is not disassembled, the first threshold, the second threshold and / or the threshold corresponding to the preset requirement are increased.

9. The control method according to any one of claims 1-4, characterized in that, Also includes: Identify the end effector installed at the end of the manipulator arm; If the end effector is a preset actuator, the first threshold, the second threshold, and / or the threshold corresponding to the preset requirement are increased.

10. A surgical robot, characterized in that, It includes a master manipulator, a slave manipulator, and a controller, wherein the slave manipulator is controlled by the master manipulator; The controller is communicatively connected to the master operating arm and the slave operating arm, and is configured to perform the control method according to any one of claims 1-9.

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