Orthopedic surgery robot calibration device and method

Abstract

The invention discloses an orthopedic surgery robot calibration device and method, and the method comprises the steps: obtaining the real-time position of a tail end execution mechanism through a position sensor, comparing the obtained real-time position of the tail end execution mechanism with the initial position of the tail end execution mechanism when the tail end execution mechanism leaves a factory, and carrying out the calibration of the real-time position of the tail end execution mechanism, obtaining a calibrated position parameter; the torque sensor is used for collecting torque parameters borne by the tail end executing mechanism, the collected torque parameters are calibrated according to the calibrated position parameters, and the calibrated torque parameters reduce operation errors of surgical instruments; the initial position of the surgical instrument is adjusted according to the calibrated position parameters, the stress condition of the surgical instrument is adjusted according to the calibration data of the torque, the position parameters are corrected firstly, then the torque parameters are corrected in an auxiliary mode through the corrected position parameters, and the surgical precision and safety of the surgical robot are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of soft tissue robots, and in particular to an orthopedic surgical robot calibration device and method. Background Art

[0002] In the medical field, especially in orthopedic surgery, surgical robots are increasingly used. Their high precision, high stability and good surgical assistance effects are widely recognized by doctors and patients. However, surgical robots still face many technical challenges in actual use, among which the calibration of position parameters and torque parameters is particularly critical. The end effector of the surgical robot is the core component of the surgical operation, and its position accuracy directly affects the surgical effect. The traditional position calibration method mainly relies on the factory setting parameters, but in the actual operation, due to various factors such as mechanical wear and environmental changes, the position of the end effector may be offset. If this offset is not calibrated in time, the surgical instrument will not be able to reach the predetermined position accurately, which will affect the accuracy and safety of the operation. When the doctor sits in front of the console and operates the surgical robot through the distal handle, a certain force needs to be applied to control the surgical instrument on the robot arm. In a specific surgical case, the doctor's goal is to remove a 5mm thick hyperplastic tissue. The doctor applies force through the distal handle to move the robotic arm of the surgical robot. This movement is achieved by the surgical instrument in the flexible channel. However, during the operation, a problem arises: the hyperplastic tissue is not completely removed. This usually means that there is a deviation between the actual moving distance of the surgical instrument and the moving instructions applied by the doctor through the distal handle. This deviation may be caused by multiple factors, but one of the key factors is that the magnitude of the force affects the accuracy of the robot's movement. In the surgical robot system, the force applied by the doctor is transmitted to the surgical instrument through a series of mechanical and electronic components. There may be some nonlinear factors in this transmission process, such as friction, elastic deformation, etc., which will cause a difference between the actual moving distance and the expected moving distance. In addition, there may be a certain lag or error in the control system of the surgical robot, which will further affect the accuracy of the operation. Therefore, when the doctor applies force through the distal handle to operate the surgical instrument, although enough force has been applied to move the surgical instrument 5mm to remove 5mm thick hyperplastic tissue, in fact, due to the influence of the above factors, the moving distance of the surgical instrument may not reach the expected 5mm, resulting in incomplete removal of the hyperplastic tissue.

[0003] For example, Chinese patent application No. 202111296911.X discloses an origin position calibration method, device, electronic device and readable storage medium, which relates to the field of soft tissue robots, including: when the end actuator and the base are detected to be engaged, obtaining the first real-time position parameter of the flexible channel of the end actuator; obtaining the initial position parameter of the flexible channel of the end actuator; obtaining the offset position parameter of the channel of the end actuator according to the difference between the first real-time position parameter and the initial position parameter; obtaining the mean position parameter of the end actuator according to the offset position parameter; obtaining the second real-time position parameter of the flexible channel; obtaining the calibration angle parameter of the end actuator according to the mean position parameter and the second real-time position parameter; calibrating the origin position of the end actuator according to the calibration angle parameter. The present invention eliminates the problem of origin position deviation caused by various uncertain factors by optimizing the determination logic of the origin position of the end actuator.

[0004] In the existing patented technology, only the position parameters of the end effector of the surgical robot are calibrated, but the torque parameters are not calibrated, which affects the accuracy of the surgery. Summary of the invention

[0005] The present application provides an orthopedic surgical robot calibration device and method, which improves the surgical accuracy and safety of the surgical robot by first correcting the position parameters and then using the corrected position parameters to assist in correcting the torque parameters. Through the correction process, the error of the position parameters can be significantly reduced.

[0006] The present application provides an orthopedic surgical robot calibration method, comprising: S101, using a position sensor to obtain a real-time position of an end actuator, comparing the obtained real-time position of the end actuator with an initial position of the end actuator set at the factory, and then calibrating the real-time position of the end actuator to obtain a calibrated position parameter; S102, using a torque sensor to collect torque parameters of the end actuator, and calibrating the collected torque parameters according to the calibrated position parameters; S103, adjusting the initial position of the surgical instrument according to the calibrated position parameters, and adjusting the force condition of the surgical instrument according to the calibration data of the torque.

[0007] Preferably, a torque correction model is established based on the obtained calibrated position parameters, and a formula is provided in the torque correction model: ,in, is the acquired torque, is the torque obtained by correcting the position parameters, It is the torque adjustment calculated based on the corrected position parameters.

[0008] Preferably, the torque adjustment ΔM is the position calibration amount A linear function, that is: ΔM= ,in, , is the linear coefficient, determined based on empirical data, and is the position parameter after calibration, and It is the real-time position parameter collected.

[0009] Preferably, the method for calibrating the torque parameters further includes: S201, based on the historical surgical data of the surgical robot, obtain the relationship between the surgical action and the torque change, identify the key points and overall trend of the torque change through the relationship between the surgical action and the torque change, and draw a torque change curve according to the relationship between the surgical action and the torque change, the key points and overall trend of the torque change; S202, inputting the torque change curve into a dynamic torque calibrator, using the dynamic torque calibrator to perform simulation calibration, simulating an expected value, using a torque sensor to measure in real time to obtain a measured value, comparing the expected value with the measured value, and obtaining a difference value; S203, calculating a calibration coefficient according to the obtained difference value; S204, verifying the calculated calibration coefficient, and substituting the verified calibration coefficient into the torque sensor in step S102 for calibration.

[0010] Preferably, the dynamic torque calibrator is set to simulation mode, and the torque change curve diagram is input into the dynamic torque calibrator as a calibration standard. The calibrator simulates the change of torque according to the set dynamic torque change curve, that is, the expected value. At the same time, the torque sensor is used for measurement, and the dynamic torque value output by the torque sensor in real time is recorded. The dynamic torque value of the torque sensor in real time is the measured value. The measured value is compared with the expected value one by one, and the measured value and the expected value at each time point are compared to obtain the difference between the measured value and the expected value.

[0011] Preferably, the calibration coefficient a is obtained by calculating the linear relationship between the measured value and the expected value, and the obtained calibration coefficient a is substituted into the formula y=ax+b, wherein y is the calibrated measured value, x is the original measured value, a is the calibration coefficient, representing the linear relationship between the measured value and the expected value, and b is the intercept.

[0012] Preferably, the method for calibrating the position parameters and torque parameters of the surgical robot according to the historical surgical data of the surgical robot also includes: when the position parameters and torque parameters are about to deviate, the fluctuation state of the position parameters and torque parameters at this time is identified, and the position parameters and torque parameters measured in real time are warned and calibrated in advance according to the identified data fluctuation state. The specific method is: S301, identifying the data fluctuation state when the position parameter and the torque parameter are about to be offset according to the collected historical data of the surgical robot; S302, using a real-time monitoring system to monitor the position parameters and torque parameters in real time, and when the real-time monitoring system detects that the data fluctuation state of the real-time position parameters and torque parameters meets the warning standard, an early warning is issued and calibration is performed; S303, dividing the deviation-sensitive area and the non-deviation-sensitive area according to the historical data of the surgical robot and the identified data fluctuation state.

[0013] Preferably, the offset state is an abnormal change of these parameters during normal operation, and the offset state is manifested as a sudden change of the parameters, exceeding a preset normal range, or a continuous unstable fluctuation.

[0014] Preferably, the method for calibrating the position parameter and the torque parameter further includes calibrating the direction of the position parameter and the torque parameter, specifically: S401, collect surgical history data, the surgical history data includes the change size and direction of position parameters and torque parameters, and calculate the size calibration factor and direction calibration factor based on the historical data: S402, calculating calibration parameters according to the calculated size calibration factor and direction calibration factor, and using the calibration parameters to calibrate the position parameters and the torque parameters.

[0015] The present application also provides an orthopedic surgical robot calibration device, including: a position sensor module, a data acquisition and processing module, a torque sensor module, a torque calibration module, an identification and warning module and a calculation module. The position sensor module and the torque sensor module are arranged on the end actuator of the surgical robot. The position sensor module and the torque sensor module are both provided with data acquisition and processing modules. The torque calibration module and the torque sensor module are electrically connected.

[0016] One or more technical solutions provided in the present application have at least the following technical effects or advantages: by first correcting the position parameters, and then using the corrected position parameters to assist in correcting the torque parameters, the surgical accuracy and safety of the surgical robot can be improved. Through the correction process, the error of the position parameters can be significantly reduced. The corrected position parameters can be used as a reference to correct the torque parameters more quickly, thereby reducing the estimated error of the torque parameters accordingly. By correcting the torque parameters, it can be ensured that the force of the surgical instrument on the tissue remains within a safe range, reducing surgical risks. Relying solely on position parameters for adjustment may result in inaccurate adjustments because other influencing factors such as torque are not considered. After adding the correction process of the torque parameters, the motion state and force conditions of the robotic arm can be more comprehensively considered, thereby improving the accuracy and safety of the adjustment. This systematic correction method helps surgical robots better adapt to complex surgical environments and improve the success rate of operations; Improving the dynamic response capability of the torque sensor so that it can better adapt to the dynamic torque changes during surgery and improve the accuracy of the torque parameters will help the surgical robot to more accurately sense and control the interaction force between surgical instruments and tissues, enhance the stability of the surgical robot during surgery, and reduce jitter and deviation during surgery. The measurement accuracy of the torque sensor under dynamic torque changes is improved, and the calibrated position parameters more accurately reflect the actual motion state of the surgical robot. The success rate and safety of the surgery are improved. By considering the impact of dynamic torque changes, the measurement accuracy of the torque sensor is significantly improved, which helps the surgical robot to more accurately control surgical instruments and reduce errors during surgery. As the accuracy of the torque parameters and the stability of the surgical robot are improved, the success rate of the surgery is also improved accordingly. This helps reduce the risk of surgical complications and recurrence and improves the quality of patient rehabilitation; Improve the calibration targeting of surgical robots, reduce the adjustment time caused by parameter offset during surgery, improve surgical efficiency and accuracy, ensure the smooth progress of the surgical process, reduce the number of surgical interruptions by calibrating in advance and focusing on sensitive areas of offset. Assuming that each adjustment in the first solution requires T minutes, the second solution reduces the number of adjustments through some improvements but still requires adjustments, and the third solution further reduces the number of adjustments to almost zero (or extremely low frequency), the total surgical time can be significantly shortened. Real-time monitoring and advance calibration ensure that the surgical robot always maintains accurate position, posture and torque parameters, reducing surgical errors. Assuming that the surgical error rate of the first solution is E1%, the second solution is reduced to E2% through some means, and the third solution is further reduced to E3% (E3 < E2 < E1) through real-time monitoring and calibration, by reducing parameter offset and adjustment times, doctors can perform surgical operations more smoothly, improving surgical experience and feel; By introducing the direction calibration factor, the calibration of position parameters and torque parameters is more accurate and targeted. Through direction calibration, the calibration error caused by direction error is reduced, making the calibrated parameters closer to the true value. Assuming that the original calibration error is ±5%, after the introduction of direction calibration, the error may be reduced to ±2% or lower. Direction calibration enables the system to better adapt to the randomness of parameter changes, especially in dynamic environments. The introduction of direction calibration further improves the calibration accuracy and the overall performance of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the flow of the orthopedic surgical robot calibration method of the present invention; Figure 2 It is a schematic diagram of the process of calibrating torque parameters according to an embodiment of the present invention; Figure 3 It is a schematic diagram of a process of early warning and early calibration of position parameters and torque parameters measured in real time according to the identified data fluctuation state according to an embodiment of the present invention; Figure 4 The figure is a schematic diagram of a flow chart of calibration of position parameters and torque parameter directions according to an embodiment of the present invention. DETAILED DESCRIPTION

[0018] To facilitate the understanding of the present invention, the present application will be described more comprehensively below with reference to the relevant drawings; the drawings show preferred embodiments of the present invention, but the present invention can be implemented in many different forms and is not limited to the embodiments described herein; on the contrary, the purpose of providing these embodiments is to enable a more thorough and comprehensive understanding of the disclosed content of the present invention.

[0019] It should be noted that the terms “vertical”, “horizontal”, “up”, “down”, “left”, “right” and similar expressions used in this document are only for illustrative purposes and do not represent the only implementation method.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs; the terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the term "and / or" used herein includes any and all combinations of one or more related listed items.

[0021] Embodiment 1: Figure 1 : is a flow chart of an orthopedic surgery robot calibration method according to an embodiment of the present invention, comprising: S101, using a position sensor to obtain a real-time position of an end actuator, comparing the obtained real-time position of the end actuator with an initial position of the end actuator set at the factory, and then calibrating the real-time position of the end actuator to obtain a calibrated position parameter; Specifically, a position sensor laser rangefinder is set on the end actuator, and the laser rangefinder is used to detect the specific position of the end actuator on the X, Y, and Z axes in real time. The end actuator includes a flexible channel and a transmission mechanism. The flexible channel can allow surgical instruments to pass through. The data acquisition system is set. By setting the data acquisition frequency, the set data acquisition frequency is greater than the movement frequency of the surgical robot to ensure that real-time position parameters can be obtained while avoiding data loss. The data acquisition system is started to start real-time acquisition of the position parameters of the end actuator on the X, Y, and Z axes, and the real-time position parameters are transmitted to the computer in the form of digital signals; the factory setting position parameters are obtained from the factory settings of the surgical robot as a reference for correction, the real-time acquired position parameters are compared with the factory setting position parameters, and the difference between the two is calculated. The calculated difference and the real-time position parameters of the end actuator are input into the Kalman filter model, and the Kalman filter model calibrates the real-time position parameters and outputs the calibrated position parameters.

[0022] S102, using a torque sensor to collect torque parameters of the end actuator, and calibrating the collected torque parameters according to the calibrated position parameters, so that the calibrated torque parameters reduce errors in the operation of the surgical instrument; Furthermore, the torque parameter reflects the interaction force between the surgical instrument and the tissue. A torque sensor is set on the end actuator of the surgical instrument, and a data acquisition system is used to record the torque parameters of the surgical instrument in real time. A moving average filter is used to smooth the torque parameters. According to the calibrated position parameters obtained in step S101, a torque correction model is established. The torque correction model is provided with a formula:

[0023] in, is the acquired torque, is the torque obtained by correcting the position parameters, It is the torque adjustment calculated based on the corrected position parameters. The torque adjustment ΔM is the position calibration value. A linear function, that is: ΔM= ,in, , is the linear coefficient, determined based on empirical data, and is the position parameter after calibration, and The real-time position parameters are collected. The calibrated position parameters and the collected torque parameters are input into the torque correction model. The torque is calibrated based on the calibrated position parameters according to the formula in the model.

[0024] For example, a surgical robot is used to remove a piece of hyperplastic tissue. The thickness of the tissue is 5mm and the expected removal depth is 4mm, that is, the surgical instrument needs to move 4mm to completely remove the hyperplastic tissue. A laser rangefinder is installed on the end effector of the surgical robot. As a position sensor, the laser rangefinder can detect the specific position of the end effector on the X, Y, and Z axes in real time. The data acquisition system is set to ensure that the data acquisition frequency is 500Hz, while the maximum movement frequency of the surgical robot is 200Hz, in order to obtain real-time position parameters and avoid data loss. The data acquisition system is started to obtain the position parameters of the end effector on the X, Y, and Z axes in real time. Assume that at a certain moment, the real-time position parameters detected by the laser rangefinder are: (105, 152, 198). The factory setting position parameters (100, 150, 200) are obtained from the factory settings of the surgical robot. The real-time position parameters are compared with the factory setting position parameters, and the difference between the two is calculated: = - =105-100=5mm, = - =152-150=2mm, = - =198-200=-2mm, the calculated difference and the real-time position parameters of the end actuator are input into the Kalman filter model, the Kalman filter model calibrates the real-time position parameters and outputs the calibrated position parameters: Assume that the calibrated position parameters are = (102.5, 149.5, 199), a torque sensor is set on the end actuator of the surgical instrument to record the torque parameters of the surgical instrument in real time. The torque parameters of the surgical instrument are recorded in real time using the data acquisition system. Assume that the torque parameter at a certain moment is =3.95 N·m, the moving average filter is used to smooth the torque parameter, and the smoothed data is still 3.95 N·m. According to the calibrated position parameter obtained in step S101, a torque correction model is established, and the torque correction model is provided with the formula: , where ΔM is the torque adjustment calculated based on the calibrated position parameters. The torque adjustment ΔM is a linear function of the position calibration, that is: ΔM = , according to the empirical data, the linear coefficient is determined as: =0.1, =0.05, =0.9, input the calibrated position parameters and the collected torque parameters into the torque correction model, and calculate the torque adjustment according to the formula in the model: ΔM =0.1×(102.5-105.0)+0.05×(149.5-152.0)+0.9×(199.0-198.0)=-0.25-0.125+0.9=0.525 Nm, therefore, the calibrated torque is: =3.95+0.525=4.475 N·m. By using the calibrated 4.475 N·m, the movement deviation is reduced from 1mm to 0.02mm. The actual resection depth = expected resection depth - movement deviation = 4mm-0.02mm=3.98mm.

[0025] S103, adjusting the initial position of the surgical instrument according to the calibrated position parameters, and adjusting the force condition of the surgical instrument according to the torque calibration data; According to the size of the position deviation, the initial position of the surgical instrument is adjusted. According to the torque correction data, the holding method of the surgical instrument is adjusted to change the force condition of the surgical instrument, thereby improving the accuracy and control precision of the operation.

[0026] The technical solution in the above-mentioned embodiment of the present application has at least the following technical effects or advantages: by first correcting the position parameters, and then using the corrected position parameters to assist in correcting the torque parameters, the surgical accuracy and safety of the surgical robot are improved. Through the correction process, the error of the position parameters can be significantly reduced. The corrected position parameters can be used as a reference to correct the torque parameters more quickly, and the estimated error of the torque parameters is also reduced accordingly. By correcting the torque parameters, it is possible to ensure that the force of the surgical instrument on the tissue remains within a safe range, reducing surgical risks. Relying solely on position parameters for adjustment may result in inaccurate adjustments because other influencing factors such as torque are not considered. After adding the correction process of the torque parameters, the motion state and force conditions of the robotic arm can be more comprehensively considered, thereby improving the accuracy and safety of the adjustment. This systematic correction method helps the surgical robot better adapt to complex surgical environments and improve the success rate of operations.

[0027] Embodiment 2: Based on the calibration process of the torque parameters in Embodiment 1, only the static torque is considered. In this embodiment, the dynamic torque change curve is introduced to calibrate the torque parameters, which can enhance the stability of the surgical robot during surgery and help reduce jitter and deviation during surgery.

[0028] like Figure 2 As shown, the method for calibrating the torque parameters also includes: S201, based on the historical surgical data of the surgical robot, obtain the relationship between the surgical action and the torque change, identify the key points and overall trend of the torque change through the relationship between the surgical action and the torque change, and draw a torque change curve according to the relationship between the surgical action and the torque change, the key points and overall trend of the torque change; Specifically, complete and accurate historical data is obtained from the storage location of the surgical robot's historical surgical data, and cases are selected according to the type of surgery, complexity of surgical movements, duration of surgery, and patient conditions to ensure that the selected cases can fully reflect the torque change characteristics of the surgical robot in different surgical scenarios. The selected surgical case data are preprocessed, including data cleaning, denoising, and alignment, to ensure the accuracy and consistency of the data. The surgical process is divided into several surgical action stages, and each stage corresponds to a specific surgical action. For each surgical action stage, the torque change data of the surgical robot is recorded, including the magnitude of the torque and the rate of change, etc. The recorded torque change data is input into the data analysis software MATLAB, and the tools in MATLAB are used to identify the peak, valley, and turning point in the torque change data. The peak is the maximum value point in the torque change data, which represents the highest level of torque reached during the operation. When identifying the peak, pay attention to the prominent points in the data. The prominent points usually correspond to specific actions in the operation, such as cutting, tightening screws, and other actions that require a large torque; the valley is The minimum point in the torque change data reflects the lowest level of torque during the operation. The valley value occurs at the transition point of the surgical action or during the rest period, when the torque demand of the surgical instrument decreases. The turning point is the point where the torque change trend changes significantly, from increase to decrease or from decrease to increase. The turning point usually marks the transition of the surgical action or operation stage. The turning point is identified by using derivatives. The torque change is analyzed for stability, periodicity and mutation. Stable torque changes indicate that the surgical process is relatively stable, while violent fluctuations may reflect complex actions or abnormal conditions during the operation. Whether the torque change is periodic is determined by identifying whether there are repeated peaks and valleys. If there are repeated peaks and valleys, it means that there is periodicity, otherwise, there is no periodicity. Observe whether there is a sudden increase or decrease in the torque change. These mutations correspond to emergencies or operational errors during the operation. The analysis of mutation helps to identify potential risk points in the surgical process. The torque change curve is drawn according to the relationship between the identified surgical action and torque change, the key points of torque change and the overall trend.

[0029] S202, inputting the torque change curve into a dynamic torque calibrator, using the dynamic torque calibrator to perform simulation calibration, simulating an expected value, using a torque sensor to measure in real time to obtain a measured value, comparing the expected value with the measured value, and obtaining a difference value; Furthermore, the dynamic torque calibrator is set to simulation mode, and the torque change curve diagram is input into the dynamic torque calibrator as a calibration standard. The calibrator simulates the change of torque according to the set dynamic torque change curve, that is, the expected value. At the same time, the torque sensor is used for measurement, and the dynamic torque value output by the torque sensor in real time is recorded. The dynamic torque value of the calibrator measured in real time by the torque sensor is the measured value. The measured value is compared with the expected value one by one, and the measured value and the expected value at each time point are compared to obtain the difference between the measured value and the expected value. The average value and standard deviation of the obtained several difference values ​​are calculated. The average value reflects the overall level of the difference value, and the standard deviation reflects the degree of fluctuation of the difference value.

[0030] S203, calculating a calibration coefficient according to the obtained difference value; Based on the measured value and the expected value obtained in step S202, the relationship between the measured value and the expected value is obtained, and the calibration coefficient a is obtained by calculating the linear relationship between the measured value and the expected value. The obtained calibration coefficient a is substituted into the formula y=ax+b, wherein y is the calibrated measured value, x is the original measured value, a is the calibration coefficient, which represents the linear relationship between the measured value and the expected value, and b is the intercept, which represents the calibrated measured value when the original measured value is 0. The intercept b is calculated by the least squares method; the calculated calibration coefficient is applied to the output end of the torque sensor to calibrate the torque sensor.

[0031] S204, verifying the calculated calibration coefficient, and substituting the verified calibration coefficient into the torque sensor in step S102 for calibration; Furthermore, using the calculated calibration coefficient, repeat the simulation calibration process in S202, record the measured value of the torque sensor again, and compare it with the expected value, analyze the difference between the measured value and the expected value before and after calibration, and evaluate whether the calibration effect is significant. If the calibration effect is significant, that is, the difference between the measured value and the expected value is significantly reduced, the calibration is successful; if the calibration effect is not ideal, adjust the calibration coefficient according to the evaluation result and repeat this step.

[0032] The final calibration coefficient is substituted into the torque sensor in step S102, and the torque sensor is calibrated by the calibration coefficient, and then the torque parameter is calibrated. By performing the reverse implementation of Example 1, that is, calibrating the torque parameter by the calibration coefficient, and calibrating the position parameter by the calibrated torque parameter, the torque sensor can accurately measure the dynamic torque change, thereby improving the surgical accuracy and safety.

[0033] The technical solution in the above-mentioned embodiment of the present application has at least the following technical effects or advantages: improving the dynamic response capability of the torque sensor so that it can better adapt to the dynamic torque changes during the operation, improving the accuracy of the torque parameters, helping the surgical robot to more accurately perceive and control the interaction force between the surgical instrument and the tissue, enhancing the stability of the surgical robot during the operation, reducing the jitter and deviation during the operation, the measurement accuracy of the torque sensor under the dynamic torque change is improved, the calibrated position parameters more accurately reflect the actual motion state of the surgical robot, the success rate and safety of the operation are improved, and by considering the influence of the dynamic torque change, the measurement accuracy of the torque sensor is significantly improved, which helps the surgical robot to more accurately control the surgical instrument and reduce the error during the operation. As the accuracy of the torque parameters and the stability of the surgical robot are improved, the success rate of the operation is also improved accordingly. This helps to reduce the risk of surgical complications and recurrence and improve the quality of rehabilitation of patients.

[0034] Example 3: Based on Example 1 and Example 2, when the surgical robot starts to be used, the doctor may not be able to find the initial position easily, causing the doctor to lose the operating feel. At the same time, during the operation of the surgical robot, the position parameters and torque parameters are prone to deviation. When deviation occurs, the operation needs to be stopped to adjust the position of the position parameters and torque parameters, which greatly affects the efficiency and accuracy of the operation. In this embodiment, the data fluctuation state of the position parameters and torque parameters when they are about to deviate is identified, and the deviation phenomenon is warned in advance, thereby reducing the number of surgical interruptions due to parameter deviation.

[0035] like Figure 3 As shown, the method for calibrating the position parameters and torque parameters of the surgical robot according to the historical surgical data of the surgical robot also includes: when the position parameters and torque parameters are about to deviate, the fluctuation state of the position parameters and torque parameters at this time is identified, and the real-time measured position parameters and torque parameters are warned and calibrated in advance according to the identified data fluctuation state. The specific method is: S301, identifying the data fluctuation state when the position parameter and the torque parameter are about to be offset according to the collected historical data of the surgical robot; Furthermore, the collected historical data of the surgical robot will be cleaned, and the outliers of the data will be detected using local anomaly factors to identify data points that deviate from the normal range. The erroneous data caused by equipment failure, operational errors, etc. will be eliminated. Finally, the cleaned data will be verified to ensure the consistency and integrity of the data. The cleaned data will be classified and divided according to dimensions such as surgery type, operation time, and robot model.

[0036] The offset state is the abnormal change of these parameters during normal working process. The offset state is manifested as sudden change of parameters, exceeding the preset normal range, or continuous unstable fluctuation. Sudden change: refers to the sharp change of parameters in a short period of time. This change may be caused by external interference, system failure or operational error. Calculate the instantaneous change rate of the parameter, that is, the ratio of the difference between the parameter values ​​at adjacent time points to the time interval, set an instantaneous change rate threshold, when the instantaneous change rate of the parameter exceeds the instantaneous change rate threshold, it is considered that a sudden change has occurred. The instantaneous change rate threshold is set by statistically analyzing the instantaneous change rate distribution of historical data, or according to business experience; Beyond the normal range: Each parameter has its normal working range. When the parameter value exceeds this range, it is considered that an offset has occurred. The normal range can be calculated based on historical data. It is set based on statistical characteristics or business experience. According to historical data or business experience, a normal value range is set for each parameter, and the parameter value is monitored in real time. When the parameter value exceeds this normal range, it is considered that an offset has occurred; continuous unstable fluctuations: refers to the continuous fluctuation of the parameter over a period of time, and the fluctuation amplitude is large and cannot remain stable. This fluctuation may be caused by the instability of the system or the continuous influence of the external environment. Within a period of time, the fluctuation amplitude of the parameter is calculated, that is, the difference between the maximum and minimum values ​​of the parameter value, and a fluctuation amplitude threshold is set. When the fluctuation amplitude of the parameter exceeds this threshold, it is considered that a continuous unstable fluctuation has occurred. The fluctuation amplitude threshold should be set based on the statistical characteristics of historical data and business needs; in the three cases of the above offset state, as long as one of the conditions is met, it is considered that the position parameter and torque parameter have offset.

[0037] According to the identification result of the offset state, the specific time point when the position parameter and the torque parameter are offset is determined. Taking into account the actual needs and data characteristics, the time window length is determined. This length should be long enough to capture the complete process of parameter fluctuation, but not too long to contain too much irrelevant information. According to the determined time window length, the data segments of the position parameter and the torque parameter are intercepted within the time range before the offset point. The fluctuation state is a specific pattern or behavior exhibited by the parameter changing over time, which may reflect the dynamic changes within the system or the interference of the external environment. According to the intercepted data segments, cluster analysis is used to identify abnormal fluctuations, that is, to identify the fluctuation state, and extract the characteristics of the fluctuation state according to the identified fluctuation state, find the maximum and minimum values ​​within the fluctuation state, and then calculate the difference between the two to calculate the fluctuation amplitude, determine the start and end time points of the fluctuation state, and calculate the time difference between these two points to extract the duration characteristics. The frequency component of the fluctuation is identified by the spectrum analysis method, and the data fluctuation state when the position parameter and the torque parameter are about to be offset is stored.

[0038] S302, using a real-time monitoring system to monitor the position parameters and torque parameters in real time, and when the real-time monitoring system detects that the data fluctuation state of the real-time position parameters and torque parameters meets the warning standard, an early warning is issued and calibration is performed; Specifically, the warning standard is that the similarity between the real-time position parameters and torque parameters and the data fluctuation state when the position parameters and torque parameters are about to offset is greater than the similarity threshold, wherein the similarity threshold is set based on experience, and the monitoring system monitors the position parameters and torque parameters of the surgical robot in real time. When the parameter changes meet the warning standard, the system immediately issues a warning signal and prepares to execute the calibration procedure. The calibration procedure is described in detail in Example 1 and Example 2 and will not be repeated here.

[0039] S303, dividing the deviation-sensitive area and the non-deviation-sensitive area according to the historical data of the surgical robot and the identified deviation state; Furthermore, based on historical data and offset status, fluctuation thresholds of position parameters and torque parameters are set. The setting of fluctuation thresholds is based on statistical methods, empirical rules or expert opinions. When the fluctuation of position parameters or torque parameters is greater than or equal to the set fluctuation threshold, the area or time period is divided into an offset sensitive area; otherwise, it is divided into a non-offset sensitive area. When the surgical robot runs into the offset sensitive area, the system needs to pay special attention and perform calibration in advance to prevent parameter offset from affecting surgical efficiency and accuracy.

[0040] The technical solutions in the above-mentioned embodiments of the present application have at least the following technical effects or advantages: improving the calibration pertinence of the surgical robot, reducing the adjustment time caused by parameter offset during the operation, improving the efficiency and accuracy of the operation, ensuring the smooth progress of the operation, reducing the number of surgical interruptions by calibrating in advance and focusing on the offset sensitive area, assuming that each adjustment in the first solution requires T minutes, the second solution reduces the number of adjustments through some improvements but still requires adjustment, and the third solution further reduces the number of adjustments to almost zero (or extremely low frequency), then the total operation time can be significantly shortened, real-time monitoring and advance calibration ensure that the surgical robot always maintains accurate position, posture and torque parameters, and reduces surgical errors. Assuming that the surgical error rate of the first solution is E1%, the second solution is reduced to E2% through some means, and the third solution is further reduced to E3% (E3 < E2 < E1) through real-time monitoring and calibration, by reducing parameter offset and adjustment times, doctors can perform surgical operations more smoothly, improving surgical experience and feel.

[0041] Embodiment 4: Based on the first three embodiments, the position parameters and torque parameters are collected and calibrated and early warning calibration is performed in advance. The change size and direction of the position parameters and torque parameters are random. The above three embodiments all describe the calibration of the change size of the position parameters and torque parameters. In this embodiment, the calibration of the direction of the position parameters and torque parameters is added.

[0042] like Figure 4 As shown, the method for calibrating the position parameter and the torque parameter also includes calibrating the direction of the position parameter and the torque parameter, specifically: S401, collecting surgical history data, the surgical history data including the magnitude and direction of changes in position parameters and torque parameters, and calculating a magnitude calibration factor and a direction calibration factor based on the historical data; Further, according to the first to third embodiments, the sizes of the position parameters and the torque parameters are calibrated, and the mean and standard deviation of the position parameters and the torque parameters in the above embodiments are calculated using statistical functions (such as mean, standard deviation adjustment function, etc.), and then the size calibration factor is calculated by the mean and standard deviation. The size calibration factor is usually used to adjust the size of the parameter change to ensure the accuracy of the calibration, and the formula is: ,in, is an adjustment factor that can be determined experimentally. is the mean, is the standard deviation, the mean and standard deviation are calculated by the collected position parameters or moment parameters; the direction calibration factor is used to identify and adjust the direction of parameter changes. It can be calculated by the direction identification function according to the directional characteristics of parameter changes, and the formula is: ,in, is the average direction change, It is a sign function, which is used to express the positive and negative of a value.

[0043] S402, calculating calibration parameters according to the calculated size calibration factor and direction calibration factor, and using the calibration parameters to calibrate the position parameters and the torque parameters; The calibration parameters are calculated using the size calibration factor and the direction calibration factor. The formula is: calibration parameter = (original parameter × size calibration factor) × direction calibration factor. The calibration parameters are used to calibrate the position parameters and torque parameters so that the calibrated parameters are closer to the true values.

[0044] The technical solutions in the above-mentioned embodiments of the present application have at least the following technical effects or advantages: by introducing a direction calibration factor, the calibration of position parameters and torque parameters is more accurate and targeted. Through direction calibration, the calibration error caused by direction error is reduced, so that the calibrated parameters are closer to the true value. Assuming that the original calibration error is ±5%, after the introduction of direction calibration, the error may be reduced to ±2% or lower. Direction calibration enables the system to better adapt to the randomness of parameter changes, especially in a dynamic environment. Through the introduction of direction calibration, the calibration accuracy and the overall performance of the system are further improved.

[0045] Embodiment 5: The orthopedic surgical robot calibration device includes: a position sensor module, a data acquisition and processing module, a torque sensor module, a torque calibration module, an identification and warning module and a calculation module. The position sensor module is used to detect the specific position of the end actuator of the surgical robot on the X, Y and Z axes in real time. High-precision sensors such as laser rangefinders are usually used to ensure the accuracy and real-time performance of data acquisition. The data acquisition and processing module is used to set the data acquisition frequency to ensure that the data acquisition frequency is greater than the movement frequency of the surgical robot to avoid data loss. The raw data is pre-processed, such as denoising and filtering. The torque sensor module Used to record the torque parameters of surgical instruments in real time; the torque calibration module is used to calibrate the collected torque parameters and simulate dynamic torque changes according to the calibrated position parameters, dynamically calibrate the torque sensor, and reduce errors in surgical instrument operations; the identification and early warning module is used to identify the data fluctuation state when the position parameters and torque parameters are about to shift, and to issue early warnings and early calibration; the calculation module is used to calculate the size calibration factor and the direction calibration factor based on historical data, and is used to calibrate the position parameters and torque parameters, calculate the calibration parameters based on the size calibration factor and the direction calibration factor, and calibrate the position parameters and torque parameters.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for calibrating an orthopedic surgical robot, characterized in that: include: S101, using a position sensor to obtain a real-time position of an end actuator, comparing the obtained real-time position of the end actuator with an initial position of the end actuator set at the factory, and then calibrating the real-time position of the end actuator to obtain a calibrated position parameter; S102, using a torque sensor to collect torque parameters of the end actuator, and calibrating the collected torque parameters according to the calibrated position parameters; S103, adjusting the initial position of the surgical instrument according to the calibrated position parameters, and adjusting the force condition of the surgical instrument according to the calibration data of the torque.

2. The orthopedic surgical robot calibration method according to claim 1, characterized in that: According to the obtained calibrated position parameters, a torque correction model is established, and the torque correction model has the formula: ,in, is the acquired torque, is the torque obtained by correcting the position parameters, It is the torque adjustment calculated based on the corrected position parameters.

3. The orthopedic surgical robot calibration method according to claim 2, characterized in that: The torque adjustment ΔM is the position calibration amount A linear function, that is: ΔM= ,in, , is the linear coefficient, determined based on empirical data, and is the position parameter after calibration, and It is the real-time position parameter collected.

4. The orthopedic surgical robot calibration method according to claim 1, characterized in that: The method for calibrating the torque parameters also includes: S201, based on the historical surgical data of the surgical robot, obtain the relationship between the surgical action and the torque change, identify the key points and overall trend of the torque change through the relationship between the surgical action and the torque change, and draw a torque change curve according to the relationship between the surgical action and the torque change, the key points and overall trend of the torque change; S202, inputting the torque change curve into a dynamic torque calibrator, using the dynamic torque calibrator to perform simulation calibration, simulating an expected value, using a torque sensor to measure in real time to obtain a measured value, comparing the expected value with the measured value, and obtaining a difference value; S203, calculating a calibration coefficient according to the obtained difference value; S204, verifying the calculated calibration coefficient, and substituting the verified calibration coefficient into the torque sensor in step S102 for calibration.

5. The orthopedic surgical robot calibration method according to claim 4, characterized in that: Set the dynamic torque calibrator to simulation mode, input the torque change curve into the dynamic torque calibrator as the calibration standard, and the calibrator simulates the change of torque according to the set dynamic torque change curve, that is, the expected value. At the same time, use the torque sensor to measure, and record the dynamic torque value output by the torque sensor real-time measurement calibrator. The dynamic torque value of the torque sensor real-time measurement calibrator is the measured value. Compare the measured value with the expected value one by one, compare the measured value and the expected value at each time point, and get the difference between the measured value and the expected value.

6. The orthopedic surgical robot calibration method according to claim 4, characterized in that: The calibration coefficient a is obtained by calculating the linear relationship between the measured value and the expected value, and the obtained calibration coefficient a is substituted into the formula y=ax+b, where y is the calibrated measured value, x is the original measured value, a is the calibration coefficient, which represents the linear relationship between the measured value and the expected value, and b is the intercept.

7. The orthopedic surgical robot calibration method according to claim 4, characterized in that: The method for calibrating the position parameters and torque parameters of the surgical robot according to the historical surgical data of the surgical robot also includes: when the position parameters and torque parameters are about to deviate, the fluctuation state of the position parameters and torque parameters at this time is identified, and the real-time measured position parameters and torque parameters are warned and calibrated in advance according to the identified data fluctuation state. The specific method is: S301, identifying the data fluctuation state when the position parameter and the torque parameter are about to be offset according to the collected historical data of the surgical robot; S302, using a real-time monitoring system to monitor the position parameters and torque parameters in real time, and when the real-time monitoring system detects that the data fluctuation state of the real-time position parameters and torque parameters meets the warning standard, an early warning is issued and calibration is performed; S303, dividing the deviation-sensitive area and the non-deviation-sensitive area according to the historical data of the surgical robot and the identified data fluctuation state.

8. The orthopedic surgical robot calibration method according to claim 7, characterized in that: The offset state is an abnormal change in the parameters during normal operation. The offset state is manifested as a sudden change in the parameters, exceeding the preset normal range, or continuous unstable fluctuations.

9. The orthopedic surgical robot calibration method according to claim 7, characterized in that: The method for calibrating the position parameters and the torque parameters also includes calibrating the directions of the position parameters and the torque parameters, specifically: S401, collect surgical history data, the surgical history data includes the change size and direction of position parameters and torque parameters, and calculate the size calibration factor and direction calibration factor based on the historical data: S402, calculating calibration parameters according to the calculated size calibration factor and direction calibration factor, and using the calibration parameters to calibrate the position parameters and the torque parameters.

10. An orthopedic surgical robot calibration device, applied to the orthopedic surgical robot calibration method according to any one of claims 1 to 9, characterized in that: include: A position sensor module, a data acquisition and processing module, a torque sensor module, a torque calibration module, an identification and warning module and a calculation module. The position sensor module and the torque sensor module are arranged on the end actuator of the surgical robot. The position sensor module and the torque sensor module are both provided with a data acquisition and processing module. The torque calibration module is electrically connected to the torque sensor module.

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