Ultrasonic knife power regulation and control method and system

Abstract

The invention provides an ultrasonic knife power regulation and control method and system, and relates to the technical field of ultrasonic knives. By judging a load impedance change source and adaptively adjusting the input power of the tool bit according to the source, the stability of the working performance of the tool bit is ensured, the cutting effect is optimized, and tissue damage is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of ultrasonic scalpel technology, and more specifically, to a method and system for controlling the power of an ultrasonic scalpel. Background Art

[0002] As an advanced surgical tool, the ultrasonic scalpel uses high-frequency ultrasonic vibrations to cut and coagulate biological tissue. Its core lies in the micron-scale vibrations of the blade driven by ultrasound. In actual surgery, biological tissue is not homogeneous, and its local physical properties, such as hardness, density, and water content, vary significantly. When the ultrasonic scalpel contacts and cuts tissues of different characteristics, the interaction force between the blade and the tissue changes accordingly. This change is directly reflected in the load of the ultrasonic scalpel system and further reflected in changes in the system's load impedance. For example, when cutting harder tissue, the load impedance generally increases; when cutting softer tissue, the load impedance may be lower.

[0003] Meanwhile, surgical procedures are typically performed by human operators, who guide the blade by holding the ultrasonic scalpel handle, applying a certain amount of downward pressure, and adjusting the cutting angle and speed. These manipulations also alter the interaction between the blade and tissue, thereby affecting the system's load impedance. For example, a sudden increase in downward pressure by the operator increases the contact pressure and friction between the blade and tissue, leading to an increase in load impedance. Rapid movement of the blade by the operator can also cause rapid changes in load.

[0004] In order to achieve adaptive power control of the ultrasonic scalpel, so that it can adjust the input power of the blade according to the actual load conditions to maintain stable cutting performance and reduce damage to tissues, it is crucial to distinguish the source of load impedance changes. Therefore, it is necessary to study an ultrasonic scalpel power control method and system that can adjust the power according to load impedance changes from different sources.

[0005] There is currently no effective technical solution to the above problems. Summary of the Invention

[0006] The purpose of this application is to provide an ultrasonic knife power control method and system, which determines the source of load impedance changes and adjusts the input power according to the source, thereby maintaining stable working performance of the knife head, optimizing cutting effects, and reducing tissue damage.

[0007] This application provides an ultrasonic knife power control method, comprising the steps of:

[0008] S1. Real-time acquisition of the amplitude signal and load impedance signal of the cutter head;

[0009] S2. Determine the source of the load impedance change based on the amplitude signal and the load impedance signal;

[0010] S3. Adjust the input power of the cutting head according to the source of the load impedance change.

[0011] Through the above settings, different adjustment methods are adopted for load impedance changes from different sources, which can make the power adjustment more targeted, ensure the stability of the blade working performance, optimize the cutting effect, and reduce tissue damage.

[0012] Optionally, step S2 includes:

[0013] Comparing the amplitude signal with a preset amplitude target value to obtain an amplitude deviation value, and calculating an amplitude deviation rate;

[0014] Analyze the power adjustment parameters to maintain the amplitude stability of the cutter head within a preset time, obtain the power adjustment amplitude, and calculate the power adjustment rate;

[0015] monitoring the load impedance signal, obtaining a load impedance change, and calculating a load impedance change rate;

[0016] The source of the load impedance change is determined according to the amplitude deviation rate, the load impedance change rate, and the power adjustment rate.

[0017] Through the above settings, the specific reasons for the load impedance change can be distinguished more accurately, providing a basis for subsequent targeted power adjustment, thereby ensuring the cutting performance of the cutter head.

[0018] Optionally, the step of determining a source of a load impedance change according to the amplitude deviation rate, the load impedance change rate, and the power adjustment rate includes:

[0019] If the load impedance change rate is greater than a preset first threshold, the amplitude deviation rate is less than a preset second threshold, and the power adjustment rate is greater than a preset third threshold, it is determined that the source of the load impedance change is operator manipulation adjustment; otherwise, it is determined that the source of the load impedance change is a difference in local tissue characteristics.

[0020] By setting clear judgment rules, the two main sources of load impedance changes can be distinguished, providing a basis for subsequent different power adjustments for different sources and improving the effectiveness of power regulation.

[0021] Optionally, step S3 includes:

[0022] Calculating a first power adjustment amount according to the amplitude signal and the preset amplitude target value;

[0023] If it is determined that the source of the load impedance change is caused by a difference in local tissue characteristics, adjusting the input power of the cutting head according to the first power adjustment amount;

[0024] If it is determined that the source of the load impedance change is caused by operator manual adjustment, a power compensation adjustment amount is obtained from a preset power compensation table based on the amplitude signal, and the power compensation adjustment amount is added to the first power adjustment amount to adjust the input power of the cutter head.

[0025] Optionally, the step of calculating the first power adjustment amount according to the amplitude signal and the preset amplitude target value includes:

[0026] Calculating an amplitude deviation value based on the amplitude signal and the preset amplitude target value;

[0027] A first power adjustment amount is calculated according to the amplitude deviation value using a proportional-integral-differential algorithm.

[0028] Optionally, the step of obtaining a power compensation adjustment amount from a preset power compensation table according to the amplitude signal includes:

[0029] Reading a power compensation table; the power compensation table is obtained by pre-building a mapping relationship between the load impedance change caused by the operator's manual adjustment and the power compensation adjustment amount;

[0030] Acquiring a plurality of load impedance signals within a preset time window;

[0031] Calculating an average of the load impedance variation according to the plurality of load impedance signals as the load impedance variation caused by the operator's manual adjustment;

[0032] According to the load impedance change caused by the operator's manual adjustment and the power compensation table, a corresponding power compensation adjustment amount is obtained.

[0033] Optionally, the step of calculating the first power adjustment amount by using a proportional-integral-differential algorithm according to the amplitude deviation value includes:

[0034] Obtaining preset proportional coefficients, integral coefficients, and differential coefficients, wherein the proportional coefficients, integral coefficients, and differential coefficients are pre-calibrated according to the size of the cutting head and the type of tissue to be cut;

[0035] Calculating a proportional term according to the amplitude deviation value and the proportional coefficient, calculating an integral term according to the integral of the amplitude deviation value and the integral coefficient, and calculating a differential term according to the differential of the amplitude deviation value and the differential coefficient;

[0036] The proportional term, the integral term, and the differential term are added together to obtain the first power adjustment amount.

[0037] Optionally, the step of analyzing a power adjustment parameter for maintaining the amplitude stability of the cutter head within a preset time to obtain a power adjustment amplitude and calculating a power adjustment rate includes:

[0038] Read the power lookup table, which is a mapping table of control signals corresponding to power adjustment parameters and power output;

[0039] Searching for a corresponding power output value according to the control signal of the power adjustment parameter, and calculating the difference between the power output values at adjacent time points to obtain a power adjustment amplitude;

[0040] The ratio of the change in the power adjustment amplitude within the preset time window to the preset time interval is calculated to obtain the power adjustment rate.

[0041] Optionally, before calculating the power adjustment rate, the method further includes:

[0042] The power adjustment amplitude is filtered.

[0043] In a second aspect, the present application provides an ultrasonic knife power control system, comprising:

[0044] An acquisition module is used to obtain the amplitude signal and load impedance signal of the cutter head in real time;

[0045] a determination module, configured to determine a source of a load impedance change based on the amplitude signal and the load impedance signal;

[0046] The adjustment module is used to adjust the input power of the cutting head according to the source of the load impedance change.

[0047] From the above, it can be seen that the ultrasonic knife power control method and system provided in this application determines the source of the load impedance change and adjusts the input power of the knife head according to the source, thereby ensuring the stability of the knife head's working performance, optimizing the cutting effect, and reducing tissue damage.

[0048] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description, or understood by practicing the embodiments of the present application. The objectives and other advantages of the present application can be achieved and obtained through the structures particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A flow chart of the ultrasonic knife power control method provided in an embodiment of the present application.

[0050] Figure 2 This is a schematic diagram of the structure of the ultrasonic knife power control system provided in an embodiment of the present application.

[0051] Explanation of reference numerals: 20, cutter head; 21, acquisition module; 211, sensor; 212, signal acquisition circuit; 22, judgment module; 221, first processor; 23, adjustment module; 231, PID control circuit; 232, second processor. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work fall within the scope of protection of the present application.

[0053] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0054] Please refer to Figure 1-Figure 2 The present application provides an ultrasonic knife power control method and system, which determines the source of load impedance change and adjusts the input power of the knife head according to the source, thereby ensuring the stability of the knife head's working performance, optimizing the cutting effect, and reducing tissue damage.

[0055] This application provides an ultrasonic knife power control method, comprising the steps of:

[0056] S1. Real-time acquisition of the amplitude signal and load impedance signal of the cutter head;

[0057] S2. Determine the source of the load impedance change based on the amplitude signal and the load impedance signal;

[0058] S3. Adjust the input power of the cutter head according to the source of the load impedance change.

[0059] The real-time acquisition of the blade's amplitude signal and load impedance signal provides fundamental data for subsequent judgment and adjustment. The amplitude signal reflects the blade's operating status, while the load impedance signal reflects the load conditions of the blade's interaction with tissue. Based on the acquired amplitude and load impedance signals, the changing characteristics of these signals are analyzed to identify the specific cause of the load impedance change. Load impedance changes can be caused by differences in local tissue characteristics or by operator manipulation. Accurately identifying the cause of load impedance changes is a prerequisite for power regulation. Based on the determined source of the load impedance change, the corresponding power level is selected to adjust the blade's input power.

[0060] Specifically, this technical solution provides an ultrasonic scalpel power control method designed to address the problem of adjusting input power based on the source of load impedance changes. This method achieves adaptive power control of the ultrasonic scalpel by acquiring key signals, determining the source of load impedance changes, and adjusting power accordingly. By adopting different adjustment methods for different sources of load impedance changes, power adjustment can be more targeted, ensuring the stability of the scalpel's operating performance, optimizing cutting results, and minimizing tissue damage.

[0061] In actual applications, the ultrasonic knife will be equipped with a sensor for real-time monitoring of the amplitude signal and load impedance signal of the blade head, and then analyze these signals to determine whether the current load impedance change is caused by a change in the characteristics of the tissue contacted by the blade head, or by a change in the pressure, speed or angle applied by the operator. Once the source of the load impedance change is determined, the processing unit sends an instruction to the power output unit according to the preset control logic. If it is determined to be a change in tissue characteristics, the first power is used to adjust the input power of the blade head; if it is determined to be an adjustment of the operator's technique, the second power is used to adjust the input power of the blade head. The input power of the blade head is then adjusted according to the first power or the second power to cope with the change in load impedance and maintain the working state of the blade head.

[0062] In some embodiments, step S2 includes:

[0063] Compare the amplitude signal with the preset amplitude target value to obtain the amplitude deviation value and calculate the amplitude deviation rate;

[0064] Analyze the power adjustment parameters to maintain the amplitude stability of the cutter head within the preset time, obtain the power adjustment amplitude, and calculate the power adjustment rate;

[0065] Monitor the load impedance signal, obtain the load impedance change, and calculate the load impedance change rate;

[0066] Determine the source of the load impedance change based on the amplitude deviation rate, load impedance change rate, and power adjustment rate.

[0067] Specifically, the system first acquires the blade's amplitude signal and load impedance signal in real time. Next, it calculates the amplitude deviation from the preset amplitude target value and the amplitude deviation rate, quantifying the extent and speed of the amplitude deviation from the target. Simultaneously, it analyzes the power adjustment parameters required to maintain blade amplitude stability within a preset timeframe, deriving the power adjustment amplitude and calculating the power adjustment rate, reflecting the intensity and speed of the power adjustment required to maintain amplitude stability. Furthermore, it monitors the load impedance signal, acquires the load impedance change, and calculates the load impedance change rate, directly quantifying the extent and speed of the load impedance change. Thus, a comprehensive assessment is made by combining the three dynamic parameters—the amplitude deviation rate, the load impedance change rate, and the power adjustment rate. For example, when the load impedance changes rapidly and the power adjustment rate is high, a low amplitude deviation rate indicates that large power adjustments have effectively maintained amplitude stability, potentially reflecting dynamic load impedance changes caused by operator manipulation. Conversely, if the load impedance change is accompanied by a high amplitude deviation rate, significant amplitude deviation persists despite power adjustment, potentially indicating that the load impedance change is due to differences in local tissue properties. By quantifying and comprehensively analyzing these parameters, this method can more accurately distinguish the specific causes of load impedance changes, providing a basis for subsequent targeted power adjustments, thereby ensuring the cutting performance of the cutter head.

[0068] In some embodiments, the step of determining the source of the load impedance change based on the amplitude deviation rate, the load impedance change rate, and the power adjustment rate includes:

[0069] If the load impedance change rate is greater than the preset first threshold, the amplitude deviation rate is less than the preset second threshold, and the power adjustment rate is greater than the preset third threshold, then it is determined that the source of the load impedance change is operator adjustment; otherwise, it is determined that the source of the load impedance change is differences in local tissue characteristics.

[0070] Specifically, this solution calculates the amplitude deviation rate, load impedance change rate, and power adjustment rate based on the real-time acquired amplitude and load impedance signals. These three calculated parameters are then compared with the preset first, second, and third thresholds, respectively. If the load impedance change rate exceeds the preset first threshold, while the amplitude deviation rate is lower than the preset second threshold and the power adjustment rate exceeds the preset third threshold, the current load impedance change is determined to be caused by operator manipulation. This combination of conditions typically corresponds to a sudden application of pressure, resulting in a rapid load increase, followed by a significant power adjustment to maintain blade amplitude stability. Otherwise, the load impedance change is determined to be caused by differences in local tissue characteristics. Load impedance changes caused by differences in local tissue characteristics can manifest in different patterns, such as a load impedance change rate lower than the preset first threshold (i.e., relatively slow change) or a significant amplitude deviation after power adjustment. These situations differ from the typical response patterns caused by operator manipulation. Thus, by establishing clear judgment rules, the two main sources of load impedance change can be distinguished, providing a basis for subsequent power adjustments tailored to each source and improving the effectiveness of power regulation.

[0071] Among them, the specific value of the preset first threshold can be calibrated through experiments: under typical operating techniques (such as rapid movement, angle adjustment), the load impedance change rate is recorded, and 95% of the data values ​​of all collected data are lower than this threshold data value as the preset first threshold; at the same time, it is verified that the preset threshold must be significantly higher than the impedance change rate caused by differences in tissue characteristics (such as the maximum change rate when cutting dense tissue).

[0072] Among them, the preset second threshold needs to be determined through a cutting experiment: under the premise of maintaining the cutting efficiency and the cutting efficiency does not drop by more than 10%, measure the amplitude deviation rate under different operating techniques (such as movement speed) and tissue types (such as liver, fascia), and take the maximum allowable value as the threshold (such as 5%).

[0073] Among them, the preset third threshold is the power adjustment rate (unit: W / s), which needs to be calibrated according to the performance of the power module of the ultrasonic knife: measure the time required for the power supply to increase from the minimum power to the maximum power, calculate the maximum allowable rate (such as 200W / s), and reserve a 20% safety margin (such as setting the threshold to 160W / s).

[0074] In practical applications, for example, the first threshold is preset to 5% / ms, the second threshold is preset to 3%, and the third threshold is preset to 2W / ms. For example, at a certain moment, the load impedance is detected to change from 100Ω to 130Ω within 5ms, and the load impedance change rate is calculated to be 6% / ms. Simultaneously, the target amplitude of the blade is 50μm, and the actual amplitude remains between 49.5μm and 50.5μm within the same time period (5ms), and the amplitude deviation rate is calculated to be 1%. Furthermore, the power output is adjusted from 30W to 45W within the same time period (5ms), and the power adjustment rate is calculated to be 3W / ms. Because the load impedance change rate (6% / ms) is greater than the first threshold (5% / ms), the amplitude deviation rate (1%) is less than the second threshold (3%), and the power adjustment rate (3W / ms) is greater than the third threshold (2W / ms), all three conditions are met, and the load impedance change is determined to be caused by operator manipulation. As another case, if the load impedance changes from 100Ω to 110Ω within 5ms, the calculated load impedance change rate is 2% / ms. At this time, even if the amplitude deviation rate and the power adjustment rate meet the conditions (i.e., the latter two conditions), since the load impedance change rate (2% / ms) is not greater than the preset first threshold (5% / ms) (i.e., the first condition is not met), it is determined that the source of the load impedance change is the difference in local tissue characteristics.

[0075] In some embodiments, step S3 includes:

[0076] Calculating a first power adjustment amount according to the amplitude signal and a preset amplitude target value;

[0077] If it is determined that the source of the load impedance change is caused by a difference in local tissue characteristics, the input power of the cutting head is adjusted according to the first power adjustment amount;

[0078] If it is determined that the source of the load impedance change is caused by operator manual adjustment, the power compensation adjustment amount is obtained from the preset power compensation table according to the amplitude signal, and the power compensation adjustment amount is added to the first power adjustment amount to adjust the input power of the cutter head.

[0079] The core of this solution lies in adjusting the blade's input power based on the source of the load impedance change. First, the blade's real-time amplitude signal is continuously monitored and compared with a preset amplitude target value. A basic power adjustment, or first power adjustment, is calculated to reflect amplitude deviations. This first power adjustment is designed to correct amplitude deviations from the target value by altering the input power. If the system determines that the load impedance change is due to the blade contacting different tissue characteristics, the calculated first power adjustment is directly used to adjust the blade's input power to maintain amplitude stability. If the system determines that the load impedance change is due to operator manipulation, such as pressure, angle, or speed, in addition to the first power adjustment, the system also consults a pre-built power compensation table based on the current amplitude signal to obtain an additional power compensation adjustment. This compensation adjustment reflects the additional power required under the load conditions caused by the specific manipulation. Finally, the first power adjustment and the power compensation adjustment are combined to form a total power adjustment, which is used to adjust the blade's input power. This approach allows the system to more accurately respond to load impedance changes from different sources, improving the adaptability of power regulation.

[0080] Specifically, this technical solution addresses the problem that a single power adjustment strategy cannot effectively address load impedance changes from different sources. First, the real-time amplitude signal of the cutting head is obtained and the preset amplitude target value is calculated. The deviation between the two is then calculated, and a first power adjustment value is calculated based on this deviation. This first power adjustment value is the basis for maintaining amplitude stability. Subsequently, different power adjustment logics are executed based on the source of the load impedance change determined in the previous step. If the load impedance change is determined to be due to local differences in tissue characteristics, indicating that the load impedance change is caused by tissue properties, the calculated first power adjustment value is directly used to adjust the cutting head input power, thereby reducing the impact of tissue property changes on the cutting head amplitude. If the load impedance change is determined to be due to operator manipulation, indicating that the load impedance change is caused by the operator's active behavior, in addition to using the first power adjustment value, a corresponding power compensation adjustment value is searched from a preset power compensation table based on the current amplitude signal. This power compensation table pre-stores the relationship between load impedance changes caused by operator manipulation and the required power compensation. The searched power compensation adjustment value is added to the first power adjustment value to obtain the final power adjustment value, which is used to adjust the cutting head input power. This superimposed adjustment method enables the system to provide more targeted compensation for dynamic load impedance changes caused by operator manipulation, thereby more effectively maintaining amplitude stability or achieving the desired surgical effect. By distinguishing the source of load impedance changes and applying corresponding adjustments, the accuracy and effectiveness of power regulation are improved.

[0081] In actual application, it is assumed that the preset amplitude target value is 50μm. The system obtains the amplitude signal of the cutter head in real time, for example, the current amplitude is 45μm. The calculated amplitude deviation is -5μm. Based on this deviation, the first power adjustment amount is calculated by the proportional integral differential algorithm, for example, +10W. At the same time, the system determines that the source of the load impedance change is caused by the operator's technique adjustment. At this time, the system consults the preset power compensation table based on the current amplitude signal (45W) or the load impedance change related to the operator's technique. The power compensation table may store the additional compensation required when the amplitude is low and the load increases due to the operating technique. For example, the power compensation adjustment amount obtained from the table is +5W. Finally, the first power adjustment amount (+10W) is superimposed on the power compensation adjustment amount (+5W) to obtain a total power adjustment amount of +15W. The input power to the cutter head is increased by 15W. If the load impedance variation is determined to be due to differences in local tissue characteristics, the system adjusts the blade input power by only the first power adjustment (+10W), increasing the input power by 10W. This provides additional power compensation for load impedance variations caused by operator manipulation, more effectively maintaining amplitude stability.

[0082] In some embodiments, the step of calculating the first power adjustment amount according to the amplitude signal and the preset amplitude target value includes:

[0083] The amplitude deviation value is calculated based on the amplitude signal and the preset amplitude target value (representing the amplitude level expected to be maintained by the tool head);

[0084] A first power adjustment amount is calculated according to the amplitude deviation value using a proportional-integral-differential algorithm.

[0085] Among them, the method of calculating the first power adjustment amount based on the amplitude signal and the preset amplitude target value first obtains the current amplitude signal of the cutter head. The amplitude signal obtained in real time is compared with the preset amplitude target value, and the difference between the two is calculated to obtain the amplitude deviation value. This deviation value reflects the gap between the current amplitude and the target amplitude. Subsequently, the calculated amplitude deviation value is used as the input of the proportional integral differential algorithm (for example, a PID controller is used to implement the calculation). The PID controller calculates an output value, namely the first power adjustment amount, based on the amplitude deviation value and its change over time. This first power adjustment amount is used for subsequent adjustment of the input power of the cutter head. The proportional integral differential algorithm combines three types of control: proportional, integral and differential. The proportion is adjusted according to the current deviation, the integral is to eliminate the steady-state error, and the differential is to predict the deviation change trend. Through these three combinations, the first power adjustment amount for power adjustment is calculated.

[0086] Specifically, to address the issue of insufficient control accuracy, slow response, or system oscillation caused by simply calculating the power adjustment, this solution uses a proportional-integral-differential (PID) algorithm to calculate the first power adjustment. First, the tool head's amplitude signal is acquired in real time and compared with the preset amplitude target value to calculate the current amplitude deviation. For example, if the preset amplitude target value is 50 μm and the current amplitude signal is 48 μm, the amplitude deviation is -2 μm. This amplitude deviation is then input into the PID controller. The PID controller calculates the proportional term, the integral term, and the differential term based on the preset proportional coefficient (Kp), integral coefficient (Ki), and differential coefficient (Kd), respectively. The proportional term is proportional to the current amplitude deviation; the integral term is proportional to the accumulation (integral) of the amplitude deviation over time; and the differential term is proportional to the rate of change (differential) of the amplitude deviation over time. These three calculated terms are summed to obtain the final first power adjustment. For example, the first power adjustment = Kp*(current deviation) + Ki*(integral of the deviation) + Kd*(differential of the deviation). This calculated first power adjustment is then used to adjust the cutter head's input power to reduce amplitude deviation and maintain the cutter head amplitude at the preset target value. The PID algorithm comprehensively considers current deviation, historical deviation, and deviation trends to calculate a more reasonable and stable first power adjustment, helping to maintain stable cutter head amplitude.

[0087] In some specific embodiments, calculating the first power adjustment value based on the amplitude signal and a preset amplitude target value can be achieved as follows: the system collects the amplitude signal of the tool head in real time, for example, every 1 millisecond. The preset amplitude target value is set to 55 microns. At a certain moment, the collected amplitude signal is 53 microns. The amplitude deviation is calculated as: 53 microns - 55 microns = -2 microns. This deviation value is input into a PID controller. The PID controller parameters are preset as: proportional coefficient Kp = 10, integral coefficient Ki = 5, and differential coefficient Kd = 2. The controller calculates the proportional term: 10 * (-2) = -20. Simultaneously, the controller accumulates historical deviations to calculate the integral term and calculates the rate of change of the current deviation to calculate the differential term. Assuming that the integral term is -5 and the differential term is -4, the calculated first power adjustment value is: -20 + (-5) + (-4) = -29. This -29 is the recommended power adjustment value, indicating that the power needs to be reduced. This calculation process is ongoing, dynamically calculating the power adjustment amount based on the real-time amplitude deviation and applying it to the ultrasonic knife's power output control loop, thereby driving the blade amplitude toward the target value of 55 microns and maintaining stability.

[0088] In some embodiments, the step of obtaining the power compensation adjustment amount from a preset power compensation table according to the amplitude signal includes:

[0089] Reading a power compensation table; the power compensation table is obtained by pre-building a mapping relationship between the load impedance change caused by the operator's manual adjustment and the power compensation adjustment amount;

[0090] Acquiring multiple load impedance signals within a preset time window;

[0091] Calculating an average of the load impedance variation according to the multiple load impedance signals as the load impedance variation caused by the operator's manual adjustment;

[0092] According to the load impedance change caused by the operator's manual adjustment and the power compensation table, the corresponding power compensation adjustment amount is obtained.

[0093] Among them, reading the power compensation table provides the basic data for compensation search. The table is obtained by pre-building the mapping relationship between the load impedance change caused by the operator's technique adjustment and the power compensation adjustment amount. Multiple load impedance signals within a preset time window are obtained, providing data samples for calculating the load impedance change. The average of the load impedance change is calculated based on the multiple load impedance signals, thereby obtaining the load impedance change representing the operator's technique adjustment. By calculating the mean, the signal fluctuation can be smoothed, and the average load impedance change caused by the operator's technique adjustment over a period of time can be more stably reflected, thereby improving the stability of the input used to search for the compensation amount. According to the load impedance change caused by the operator's technique adjustment and the power compensation table, the corresponding power compensation adjustment amount is obtained. Using the calculated load impedance change for search, the power compensation value required for the operator's technique adjustment can be directly obtained, thereby improving the pertinence of the power compensation.

[0094] Specifically, this solution provides a method for obtaining a power compensation adjustment, which is used to adjust the input power of the cutting head when the source of the load impedance change is determined to be caused by operator manipulation. First, a pre-established power compensation table is read. This table establishes a correspondence between the load impedance change caused by operator manipulation and the required power compensation adjustment. Next, multiple load impedance signals are acquired within a preset time window. For example, 100 load impedance signals are acquired at a sampling rate of 100 Hz within a 1-second time window. Then, based on the multiple acquired load impedance signals, the mean of the load impedance change is calculated. For example, the mean of the load impedance change at each sampling point within the time window relative to the load impedance at the window start point is calculated, or the mean of the load impedance changes at adjacent sampling points is calculated. This mean is determined as the load impedance change caused by operator manipulation. Finally, the calculated load impedance change representing the operator manipulation change is used as input to search the power compensation table for the corresponding power compensation adjustment. Because the power compensation table is constructed based on the load impedance change from this specific source, the power compensation value required for the operator's manual adjustment can be directly obtained by using the calculated load impedance change for lookup. By calculating the load impedance change caused by the operator's manual adjustment and using this as a basis for looking up the compensation value in the table, this solution directly links the specific cause of the load impedance change with the required compensation amount, thereby improving the accuracy of power compensation.

[0095] In some specific embodiments, a power compensation table can be constructed in advance through experimental calibration. For example, in a simulated surgical scenario, by simulating different operator adjustments (such as changes in pressure and movement speed), the resulting load impedance changes are recorded, and the additional power adjustment required to maintain amplitude stability is also recorded. This data is processed to construct a mapping relationship between the load impedance change and the required power compensation adjustment, forming a power compensation table. In actual applications, a preset time window is set, such as 0.5 seconds. The system continuously collects load impedance signals within this window. Assume that a series of load impedance values are collected within a 0.5-second window, and the average change of these values relative to the window starting value is calculated to be +50Ω. The system reads a preset power compensation table, which may contain the following entries: a load impedance change of +20Ω corresponds to a compensation of +1W, +40Ω corresponds to a compensation of +2W, and +60Ω corresponds to a compensation of +3W. Through table lookup or interpolation calculation, the power compensation adjustment corresponding to a load impedance change of +50Ω may be determined to be +2.5W. This +2.5W compensation is then added to the first power adjustment calculated based on the amplitude deviation to determine the final input power adjustment. This allows the system to provide more precise power compensation for load impedance changes caused by operator technique, helping to maintain stable cutter head amplitude.

[0096] In some embodiments, the step of calculating the first power adjustment amount using a proportional-integral-differential algorithm according to the amplitude deviation value includes:

[0097] Obtaining preset proportional coefficients, integral coefficients, and differential coefficients, wherein the proportional coefficients, integral coefficients, and differential coefficients are pre-calibrated according to the size of the cutting head and the type of tissue to be cut;

[0098] The proportional term is calculated based on the amplitude deviation value and the proportional coefficient, the integral term is calculated based on the integral of the amplitude deviation value and the integral coefficient, and the differential term is calculated based on the differential of the amplitude deviation value and the differential coefficient;

[0099] The proportional term, the integral term, and the differential term are added together to obtain a first power adjustment amount.

[0100] Among them, the technical solution elaborates in detail how to use the proportional-integral-differential algorithm to calculate the first power adjustment amount. First, obtain the preset proportional coefficient, integral coefficient and differential coefficient. These coefficients are the core parameters of the proportional-integral-differential controller. By pre-calibrating these coefficients according to the size of the blade and the type of cut tissue, the proportional-integral-differential controller can be optimized and adjusted for different ultrasonic knife systems. This solves the problem of poor control performance caused by coefficient mismatch when simply applying the proportional-integral-differential algorithm, and ensures the adaptability and effectiveness of the controller in different surgical environments. Then, the proportional term is calculated by multiplying the current amplitude deviation value by the proportional coefficient. The integral term is calculated by multiplying the cumulative integral of the amplitude deviation value by the integral coefficient. The differential term is calculated by multiplying the rate of change of the amplitude deviation value by the differential coefficient. Finally, the calculated proportional term, integral term and differential term are superimposed to obtain the final first power adjustment amount.

[0101] Specifically, since the control effect of the proportional-integral-differential algorithm depends on the selection of the proportional coefficient, integral coefficient and differential coefficient, if these coefficients are not properly set or adjusted according to the actual situation, it may lead to inaccurate power adjustment, slow response or excessive oscillation, and the blade amplitude cannot be effectively maintained stable, affecting the cutting performance and safety. By pre-calibrating the proportional coefficient, integral coefficient and differential coefficient according to the size of the blade and the type of cutting tissue, the proportional-integral-differential algorithm can be optimized and adjusted for different blades and cutting tissues. Therefore, according to the amplitude deviation value, these preset coefficients are used to calculate the proportional term, integral term and differential term, and they are added together to obtain the first power adjustment amount, ensuring that the first power adjustment amount calculated according to the amplitude deviation can accurately adjust the input power of the blade, thereby effectively maintaining the blade amplitude near the target value, ensuring the cutting performance and safety of the ultrasonic knife in different surgical scenarios.

[0102] In some specific embodiments, for example, when using a blade of a specific size (e.g., 5 mm in diameter) to cut liver tissue, a set of proportional coefficients, integral coefficients, and differential coefficients (e.g., Kp=10, Ki=2, Kd=0.5) are pre-calibrated for the blade size and tissue type. During the operation, the amplitude signal of the blade is acquired in real time, and the deviation value between it and the preset amplitude target value (e.g., 50 microns) is calculated. If the current amplitude deviation value is +5 microns, the proportional term is calculated as 10*5=50. At the same time, the integral term and the differential term are calculated based on the integral of the historical amplitude deviation value and the rate of change of the current amplitude deviation value, for example, the integral term is 2*(historical deviation integral) and the differential term is 0.5*(deviation change rate). These three terms are added together to obtain the first power adjustment amount.

[0103] In some embodiments, the step of analyzing a power adjustment parameter for maintaining a stable amplitude of the cutting head within a preset time to obtain a power adjustment amplitude and calculating a power adjustment rate includes:

[0104] Read the power lookup table, which is a mapping table of control signals corresponding to power adjustment parameters and power output;

[0105] Find the corresponding power output value according to the control signal of the power adjustment parameter, and calculate the difference between the power output values at adjacent time points to obtain the power adjustment amplitude;

[0106] The ratio of the change in the power adjustment amplitude within the preset time window to the preset time interval is calculated to obtain the power adjustment rate.

[0107] In some implementations, before the step of calculating the power adjustment rate, the method further includes:

[0108] Perform filtering on the power adjustment amplitude.

[0109] Among them, the method includes reading a power lookup table, which establishes a mapping relationship between the control signal corresponding to the power adjustment parameter and the power output. By reading the table, the internal control signal can be converted into an actual power output value. Furthermore, according to the control signal of the power adjustment parameter, the corresponding power output value is found in the power lookup table. By calculating the difference between the power output values obtained at adjacent time points, the power adjustment amplitude can be obtained, which quantifies the change in power adjustment performed in a short period of time to maintain the stability of the blade amplitude. Thus, the ratio of the change in the power adjustment amplitude within a preset time window to the preset time interval is calculated to obtain the power adjustment rate, which reflects the trend of the speed of the power adjustment over time.

[0110] Specifically, to determine the source of load impedance variation, it is necessary to quantify the power adjustment behavior required to maintain blade head amplitude stability. First, a pre-stored power lookup table is read, which records the actual power output values corresponding to different control signals. For example, the control signal may be a digital quantity, while the power output is expressed in watts. Next, the control signal corresponding to the power adjustment parameter is acquired in real time. Using this control signal, the corresponding actual power output value is found in the power lookup table. A series of power output values are acquired at consecutive sampling points, and the instantaneous power adjustment amplitude is calculated by calculating the difference between the power output values at two adjacent sampling points. To obtain more stable rate information, the changes in these power adjustment amplitudes are accumulated or averaged over a preset time window (e.g., N consecutive sampling points). This change is then divided by the total duration of the time window or the sampling interval to calculate the power adjustment rate. This power adjustment rate provides quantitative information about the power adjustment trend. The calculated power adjustment amplitude and power adjustment rate, combined with the amplitude deviation rate and load impedance change rate, can be used as input data to subsequently determine the specific source of the load impedance variation, such as whether it is due to operator manipulation or differences in local tissue characteristics. By providing this quantitative power adjustment information, the cause of the load impedance change can be more accurately identified, allowing more targeted power control methods to be adopted.

[0111] In some specific embodiments, the power lookup table can be stored as a two-dimensional array, with the first column containing control signal values (e.g., integers from 0 to 255) and the second column containing corresponding power output values (e.g., from 0 to 100 W). The control signal is acquired at a sampling rate of 100 Hz. During each sampling period, the current control signal is read and the corresponding power output value is found in the lookup table. For example, if the current control signal is 150, the lookup table indicates a corresponding power of 60 W. In the next sampling period, if the control signal changes to 155, the corresponding power is 62 W. The power adjustment amplitude during this sampling interval is 62 W - 60 W = 2 W. To calculate the power adjustment rate, a preset time window of 10 sampling periods (i.e., 0.1 seconds) can be set. Within this window, the absolute values of the power adjustment amplitudes calculated for each sampling period are accumulated, for example, if the total is 15 W. The power adjustment rate can then be calculated as 15 W / 0.1 seconds = 150 W / s. The calculated power adjustment amplitude and rate are then used to determine the source of the load impedance change.

[0112] In some implementations, before the step of calculating the power adjustment rate, the method further includes:

[0113] Perform filtering on the power adjustment amplitude.

[0114] Filtering the power adjustment amplitude can reduce the noise component in the power adjustment amplitude and reduce data volatility, thereby improving the reliability of subsequent power adjustment rate calculation. Filtering can be implemented using various signal processing methods, such as digital filters.

[0115] Specifically, after obtaining the power adjustment amplitude, it is input into a filter module. The filter module processes the input power adjustment amplitude data according to a preset filtering algorithm. The noise component of the processed power adjustment amplitude data is reduced and the volatility is reduced. Subsequently, the power adjustment rate is calculated using the filtered power adjustment amplitude data. The calculated power adjustment rate data has higher reliability and helps to improve the accuracy of judging the source of load impedance changes. Accurate judgment of the source of load impedance changes enables the power control system to more accurately make corresponding power adjustments based on the source of load impedance changes, thereby optimizing the performance of the ultrasonic knife.

[0116] In some specific embodiments, a sliding average filter can be used to filter the power adjustment amplitude. For example, a time window of length N is set. At each time point, the power adjustment amplitude data for the current time point and the previous N-1 time points are obtained. The average of these N power adjustment amplitude data is calculated, and this average is used as the filtered power adjustment amplitude at the current time point. This smoothes out the instantaneous spikes and random noise in the original power adjustment amplitude data, resulting in a more stable filtered data sequence. Calculating the power adjustment rate based on this stable sequence can reduce the deviation of the calculation result and improve the accuracy of the judgment.

[0117] In a second aspect, the present application provides an ultrasonic knife power control system, comprising:

[0118] An acquisition module 21 is used to acquire the amplitude signal and load impedance signal of the cutter head in real time;

[0119] A determination module 22 is configured to determine a source of a load impedance change based on the amplitude signal and the load impedance signal;

[0120] The adjustment module 23 is used to adjust the input power of the cutter head according to the source of the load impedance change.

[0121] Please refer to Figure 2The acquisition module 21 is connected to the blade head and is used to collect the amplitude signal reflecting the motion state of the blade head and the load impedance signal reflecting the interaction between the blade head and the tissue. The acquisition module 21 may include a sensor and a signal acquisition circuit. The judgment module 22 receives the amplitude signal and the load impedance signal output by the acquisition module 21, and performs analysis to distinguish the specific reasons for the change in load impedance. The judgment module 22 can be implemented by the first processor executing a specific algorithm. The adjustment module 23 receives the judgment result of the judgment module 22 and the signal of the acquisition module 21, and calculates the power adjustment amount based on the judgment result. The adjustment module 23 outputs a control signal to the drive circuit of the blade head to change the input power of the blade head. The adjustment module 23 can be implemented by the second processor and the PID control circuit. Thus, the ultrasonic knife power control system realizes adaptive control of the ultrasonic knife input power through the coordinated work of each module. Among them, the sensor, signal acquisition circuit, first processor, second processor and PID control circuit are all existing technologies and will not be described in detail here.

[0122] Specifically, during an ultrasonic scalpel operation, the blade contacts biological tissue, and differences in the local characteristics of the tissue or adjustments made by the operator can cause changes in the load impedance. To maintain stable blade performance, targeted power adjustments are required based on the source of the load impedance change. The ultrasonic scalpel power control system monitors the blade's amplitude and load impedance in real time through the acquisition module 21, and inputs these signals into the judgment module 22. The judgment module 22 analyzes these signals to identify whether the load impedance change is caused by local tissue characteristics or by adjustments made by the operator. If it is determined to be a change in tissue characteristics, the adjustment module 23 may calculate a power adjustment based on the amplitude deviation to maintain amplitude stability. If it is determined to be an adjustment made by the operator, the adjustment module 23 may, on top of maintaining amplitude stability, superimpose an additional power compensation adjustment to account for changes in load impedance caused by the operator. The adjustment module 23 converts the calculated power adjustment into a control signal, which acts on the power output unit of the ultrasonic scalpel, thereby adjusting the input power of the blade. Therefore, the ultrasonic scalpel power control system can distinguish the source of load impedance changes and take corresponding power adjustment measures, which improves the power control accuracy and adaptability of the ultrasonic scalpel, helps maintain the cutting performance of the blade and reduce tissue damage.

[0123] The real-time acquisition of the blade's amplitude signal and load impedance signal provides fundamental data for subsequent judgment and adjustment. The amplitude signal reflects the blade's operating status, while the load impedance signal reflects the load conditions of the blade's interaction with tissue. Based on the acquired amplitude and load impedance signals, the changing characteristics of these signals are analyzed to identify the specific cause of the load impedance change. Load impedance changes can be caused by differences in local tissue characteristics or by operator manipulation. Accurately identifying the cause of load impedance changes is a prerequisite for power regulation. Based on the determined source of the load impedance change, the corresponding power level is selected to adjust the blade's input power.

[0124] Specifically, this technical solution provides an ultrasonic scalpel power control method designed to address the problem of adjusting input power based on the source of load impedance changes. This method achieves adaptive power control of the ultrasonic scalpel by acquiring key signals, determining the source of load impedance changes, and adjusting power accordingly. By adopting different adjustment methods for different sources of load impedance changes, power adjustment can be more targeted, ensuring the stability of the scalpel's operating performance, optimizing cutting results, and minimizing tissue damage.

[0125] In actual applications, the ultrasonic knife will be equipped with a sensor for real-time monitoring of the amplitude signal and load impedance signal of the blade head, and then analyze these signals to determine whether the current load impedance change is caused by a change in the characteristics of the tissue contacted by the blade head, or by a change in the pressure, speed or angle applied by the operator. Once the source of the load impedance change is determined, the processing unit sends an instruction to the power output unit according to the preset control logic. If it is determined to be a change in tissue characteristics, the first power is used to adjust the input power of the blade head; if it is determined to be an adjustment of the operator's technique, the second power is used to adjust the input power of the blade head. The input power of the blade head is then adjusted according to the first power or the second power to cope with the change in load impedance and maintain the working state of the blade head.

[0126] In some embodiments, when determining the source of the load impedance change based on the amplitude signal and the load impedance signal, the determination module 22 specifically performs:

[0127] Compare the amplitude signal with the preset amplitude target value to obtain the amplitude deviation value and calculate the amplitude deviation rate;

[0128] Analyze the power adjustment parameters to maintain the amplitude stability of the cutter head within the preset time, obtain the power adjustment amplitude, and calculate the power adjustment rate;

[0129] Monitor the load impedance signal, obtain the load impedance change, and calculate the load impedance change rate;

[0130] Determine the source of the load impedance change based on the amplitude deviation rate, load impedance change rate, and power adjustment rate.

[0131] Specifically, the system first acquires the blade's amplitude signal and load impedance signal in real time. Next, it calculates the amplitude deviation from the preset amplitude target value and the amplitude deviation rate, quantifying the extent and speed of the amplitude deviation from the target. Simultaneously, it analyzes the power adjustment parameters required to maintain blade amplitude stability within a preset timeframe, deriving the power adjustment amplitude and calculating the power adjustment rate, reflecting the intensity and speed of the power adjustment required to maintain amplitude stability. Furthermore, it monitors the load impedance signal, acquires the load impedance change, and calculates the load impedance change rate, directly quantifying the extent and speed of the load impedance change. Thus, a comprehensive assessment is made by combining the three dynamic parameters—the amplitude deviation rate, the load impedance change rate, and the power adjustment rate. For example, when the load impedance changes rapidly and the power adjustment rate is high, a low amplitude deviation rate indicates that large power adjustments have effectively maintained amplitude stability, potentially reflecting dynamic load impedance changes caused by operator manipulation. Conversely, if the load impedance change is accompanied by a high amplitude deviation rate, significant amplitude deviation persists despite power adjustment, potentially indicating that the load impedance change is due to differences in local tissue properties. By quantifying and comprehensively analyzing these parameters, this method can more accurately distinguish the specific causes of load impedance changes, providing a basis for subsequent targeted power adjustments, thereby ensuring the cutting performance of the cutter head.

[0132] In some embodiments, when determining the source of the load impedance change based on the amplitude deviation rate, the load impedance change rate, and the power adjustment rate, the determination module 22 specifically performs:

[0133] If the load impedance change rate is greater than the preset first threshold, the amplitude deviation rate is less than the preset second threshold, and the power adjustment rate is greater than the preset third threshold, then it is determined that the source of the load impedance change is operator adjustment; otherwise, it is determined that the source of the load impedance change is differences in local tissue characteristics.

[0134] Specifically, this solution calculates the amplitude deviation rate, load impedance change rate, and power adjustment rate based on the real-time acquired amplitude and load impedance signals. These three calculated parameters are then compared with the preset first, second, and third thresholds, respectively. If the load impedance change rate exceeds the preset first threshold, while the amplitude deviation rate is lower than the preset second threshold and the power adjustment rate exceeds the preset third threshold, the current load impedance change is determined to be caused by operator manipulation. This combination of conditions typically corresponds to a sudden application of pressure, resulting in a rapid load increase, followed by a significant power adjustment to maintain blade amplitude stability. Otherwise, the load impedance change is determined to be caused by differences in local tissue characteristics. Load impedance changes caused by differences in local tissue characteristics can manifest in different patterns, such as a load impedance change rate lower than the preset first threshold (i.e., relatively slow change) or a significant amplitude deviation after power adjustment. These situations differ from the typical response patterns caused by operator manipulation. Thus, by establishing clear judgment rules, the two main sources of load impedance change can be distinguished, providing a basis for subsequent power adjustments tailored to each source and improving the effectiveness of power regulation.

[0135] Among them, the specific value of the preset first threshold can be calibrated through experiments: under typical operating techniques (such as rapid movement, angle adjustment), the load impedance change rate is recorded, and 95% of the data values ​​of all collected data are lower than this threshold data value as the preset first threshold; at the same time, it is verified that the preset threshold must be significantly higher than the impedance change rate caused by differences in tissue characteristics (such as the maximum change rate when cutting dense tissue).

[0136] Among them, the preset second threshold needs to be determined through a cutting experiment: under the premise of maintaining the cutting efficiency and the cutting efficiency does not drop by more than 10%, measure the amplitude deviation rate under different operating techniques (such as movement speed) and tissue types (such as liver, fascia), and take the maximum allowable value as the threshold (such as 5%).

[0137] Among them, the preset third threshold is the power adjustment rate (unit: W / s), which needs to be calibrated according to the performance of the power module of the ultrasonic knife: measure the time required for the power supply to increase from the minimum power to the maximum power, calculate the maximum allowable rate (such as 200W / s), and reserve a 20% safety margin (such as setting the threshold to 160W / s).

[0138] In practical applications, for example, the first threshold is preset to 5% / ms, the second threshold is preset to 3%, and the third threshold is preset to 2W / ms. For example, at a certain moment, the load impedance is detected to change from 100Ω to 130Ω within 5ms, and the load impedance change rate is calculated to be 6% / ms. Simultaneously, the target amplitude of the blade is 50μm, and the actual amplitude remains between 49.5μm and 50.5μm within the same time period (5ms), and the amplitude deviation rate is calculated to be 1%. Furthermore, the power output is adjusted from 30W to 45W within the same time period (5ms), and the power adjustment rate is calculated to be 3W / ms. Because the load impedance change rate (6% / ms) is greater than the first threshold (5% / ms), the amplitude deviation rate (1%) is less than the second threshold (3%), and the power adjustment rate (3W / ms) is greater than the third threshold (2W / ms), all three conditions are met, and the load impedance change is determined to be caused by operator manipulation. As another case, if the load impedance changes from 100Ω to 110Ω within 5ms, the calculated load impedance change rate is 2% / ms. At this time, even if the amplitude deviation rate and the power adjustment rate meet the conditions (i.e., the latter two conditions), since the load impedance change rate (2% / ms) is not greater than the preset first threshold (5% / ms) (i.e., the first condition is not met), it is determined that the source of the load impedance change is the difference in local tissue characteristics.

[0139] In some embodiments, when adjusting the input power of the cutter head according to the source of the load impedance change, the adjustment module 23 specifically performs:

[0140] Calculating a first power adjustment amount according to the amplitude signal and a preset amplitude target value;

[0141] If it is determined that the source of the load impedance change is caused by a difference in local tissue characteristics, the input power of the cutting head is adjusted according to the first power adjustment amount;

[0142] If it is determined that the source of the load impedance change is caused by operator manual adjustment, the power compensation adjustment amount is obtained from the preset power compensation table according to the amplitude signal, and the power compensation adjustment amount is added to the first power adjustment amount to adjust the input power of the cutter head.

[0143] The core of this solution lies in adjusting the blade's input power based on the source of the load impedance change. First, the blade's real-time amplitude signal is continuously monitored and compared with a preset amplitude target value. A basic power adjustment, or first power adjustment, is calculated to reflect amplitude deviations. This first power adjustment is designed to correct amplitude deviations from the target value by altering the input power. If the system determines that the load impedance change is due to the blade contacting different tissue characteristics, the calculated first power adjustment is directly used to adjust the blade's input power to maintain amplitude stability. If the system determines that the load impedance change is due to operator manipulation, such as pressure, angle, or speed, in addition to the first power adjustment, the system also consults a pre-built power compensation table based on the current amplitude signal to obtain an additional power compensation adjustment. This compensation adjustment reflects the additional power required under the load conditions caused by the specific manipulation. Finally, the first power adjustment and the power compensation adjustment are combined to form a total power adjustment, which is used to adjust the blade's input power. This approach allows the system to more accurately respond to load impedance changes from different sources, improving the adaptability of power regulation.

[0144] Specifically, this technical solution addresses the problem that a single power adjustment strategy cannot effectively address load impedance changes from different sources. First, the real-time amplitude signal of the cutting head is obtained and the preset amplitude target value is calculated. The deviation between the two is then calculated, and a first power adjustment value is calculated based on this deviation. This first power adjustment value is the basis for maintaining amplitude stability. Subsequently, different power adjustment logics are executed based on the source of the load impedance change determined in the previous step. If the load impedance change is determined to be due to local differences in tissue characteristics, indicating that the load impedance change is caused by tissue properties, the calculated first power adjustment value is directly used to adjust the cutting head input power, thereby reducing the impact of tissue property changes on the cutting head amplitude. If the load impedance change is determined to be due to operator manipulation, indicating that the load impedance change is caused by the operator's active behavior, in addition to using the first power adjustment value, a corresponding power compensation adjustment value is searched from a preset power compensation table based on the current amplitude signal. This power compensation table pre-stores the relationship between load impedance changes caused by operator manipulation and the required power compensation. The searched power compensation adjustment value is added to the first power adjustment value to obtain the final power adjustment value, which is used to adjust the cutting head input power. This superimposed adjustment method enables the system to provide more targeted compensation for dynamic load impedance changes caused by operator manipulation, thereby more effectively maintaining amplitude stability or achieving the desired surgical effect. By distinguishing the source of load impedance changes and applying corresponding adjustments, the accuracy and effectiveness of power regulation are improved.

[0145] In actual application, it is assumed that the preset amplitude target value is 50μm. The system obtains the amplitude signal of the cutter head in real time, for example, the current amplitude is 45μm. The calculated amplitude deviation is -5μm. Based on this deviation, the first power adjustment amount is calculated by the proportional integral differential algorithm, for example, +10W. At the same time, the system determines that the source of the load impedance change is caused by the operator's technique adjustment. At this time, the system consults the preset power compensation table based on the current amplitude signal (45W) or the load impedance change related to the operator's technique. The power compensation table may store the additional compensation required when the amplitude is low and the load increases due to the operating technique. For example, the power compensation adjustment amount obtained from the table is +5W. Finally, the first power adjustment amount (+10W) is superimposed on the power compensation adjustment amount (+5W) to obtain a total power adjustment amount of +15W. The input power to the cutter head is increased by 15W. If the load impedance variation is determined to be due to differences in local tissue characteristics, the system adjusts the blade input power by only the first power adjustment (+10W), increasing the input power by 10W. This provides additional power compensation for load impedance variations caused by operator manipulation, more effectively maintaining amplitude stability.

[0146] In some embodiments, the step of calculating the first power adjustment amount according to the amplitude signal and the preset amplitude target value includes:

[0147] The amplitude deviation value is calculated based on the amplitude signal and the preset amplitude target value (representing the amplitude level expected to be maintained by the tool head);

[0148] A first power adjustment amount is calculated according to the amplitude deviation value using a proportional-integral-differential algorithm.

[0149] Among them, the method of calculating the first power adjustment amount based on the amplitude signal and the preset amplitude target value first obtains the current amplitude signal of the cutter head. The amplitude signal obtained in real time is compared with the preset amplitude target value, and the difference between the two is calculated to obtain the amplitude deviation value. This deviation value reflects the gap between the current amplitude and the target amplitude. Subsequently, the calculated amplitude deviation value is used as the input of the proportional integral differential algorithm (for example, a PID controller is used to implement the calculation). The PID controller calculates an output value, namely the first power adjustment amount, based on the amplitude deviation value and its change over time. This first power adjustment amount is used for subsequent adjustment of the input power of the cutter head. The proportional integral differential algorithm combines three types of control: proportional, integral and differential. The proportion is adjusted according to the current deviation, the integral is to eliminate the steady-state error, and the differential is to predict the deviation change trend. Through these three combinations, the first power adjustment amount for power adjustment is calculated.

[0150] Specifically, to address the issue of insufficient control accuracy, slow response, or system oscillation caused by simply calculating the power adjustment, this solution uses a proportional-integral-differential (PID) algorithm to calculate the first power adjustment. First, the tool head's amplitude signal is acquired in real time and compared with the preset amplitude target value to calculate the current amplitude deviation. For example, if the preset amplitude target value is 50 μm and the current amplitude signal is 48 μm, the amplitude deviation is -2 μm. This amplitude deviation is then input into the PID controller. The PID controller calculates the proportional term, the integral term, and the differential term based on the preset proportional coefficient (Kp), integral coefficient (Ki), and differential coefficient (Kd), respectively. The proportional term is proportional to the current amplitude deviation; the integral term is proportional to the accumulation (integral) of the amplitude deviation over time; and the differential term is proportional to the rate of change (differential) of the amplitude deviation over time. These three calculated terms are summed to obtain the final first power adjustment. For example, the first power adjustment = Kp*(current deviation) + Ki*(integral of the deviation) + Kd*(differential of the deviation). This calculated first power adjustment is then used to adjust the cutter head's input power to reduce amplitude deviation and maintain the cutter head amplitude at the preset target value. The PID algorithm comprehensively considers current deviation, historical deviation, and deviation trends to calculate a more reasonable and stable first power adjustment, helping to maintain stable cutter head amplitude.

[0151] In some specific embodiments, calculating the first power adjustment value based on the amplitude signal and a preset amplitude target value can be achieved as follows: the system collects the amplitude signal of the tool head in real time, for example, every 1 millisecond. The preset amplitude target value is set to 55 microns. At a certain moment, the collected amplitude signal is 53 microns. The amplitude deviation is calculated as: 53 microns - 55 microns = -2 microns. This deviation value is input into a PID controller. The PID controller parameters are preset as: proportional coefficient Kp = 10, integral coefficient Ki = 5, and differential coefficient Kd = 2. The controller calculates the proportional term: 10 * (-2) = -20. Simultaneously, the controller accumulates historical deviations to calculate the integral term and calculates the rate of change of the current deviation to calculate the differential term. Assuming that the integral term is -5 and the differential term is -4, the calculated first power adjustment value is: -20 + (-5) + (-4) = -29. This -29 is the recommended power adjustment value, indicating that the power needs to be reduced. This calculation process is ongoing, dynamically calculating the power adjustment amount based on the real-time amplitude deviation and applying it to the ultrasonic knife's power output control loop, thereby driving the blade amplitude toward the target value of 55 microns and maintaining stability.

[0152] In some embodiments, when the adjustment module 23 obtains the power compensation adjustment amount from the preset power compensation table according to the amplitude signal, it specifically performs:

[0153] Reading a power compensation table; the power compensation table is obtained by pre-building a mapping relationship between the load impedance change caused by the operator's manual adjustment and the power compensation adjustment amount;

[0154] Acquiring multiple load impedance signals within a preset time window;

[0155] Calculating an average of the load impedance variation according to the multiple load impedance signals as the load impedance variation caused by the operator's manual adjustment;

[0156] According to the load impedance change caused by the operator's manual adjustment and the power compensation table, the corresponding power compensation adjustment amount is obtained.

[0157] Among them, reading the power compensation table provides the basic data for compensation search. The table is obtained by pre-building the mapping relationship between the load impedance change caused by the operator's technique adjustment and the power compensation adjustment amount. Multiple load impedance signals within a preset time window are obtained, providing data samples for calculating the load impedance change. The average of the load impedance change is calculated based on the multiple load impedance signals, thereby obtaining the load impedance change representing the operator's technique adjustment. By calculating the mean, the signal fluctuation can be smoothed, and the average load impedance change caused by the operator's technique adjustment over a period of time can be more stably reflected, thereby improving the stability of the input used to search for the compensation amount. According to the load impedance change caused by the operator's technique adjustment and the power compensation table, the corresponding power compensation adjustment amount is obtained. Using the calculated load impedance change for search, the power compensation value required for the operator's technique adjustment can be directly obtained, thereby improving the pertinence of the power compensation.

[0158] Specifically, this solution provides a method for obtaining a power compensation adjustment, which is used to adjust the input power of the cutting head when the source of the load impedance change is determined to be caused by operator manipulation. First, a pre-established power compensation table is read. This table establishes a correspondence between the load impedance change caused by operator manipulation and the required power compensation adjustment. Next, multiple load impedance signals are acquired within a preset time window. For example, 100 load impedance signals are acquired at a sampling rate of 100 Hz within a 1-second time window. Then, based on the multiple acquired load impedance signals, the mean of the load impedance change is calculated. For example, the mean of the load impedance change at each sampling point within the time window relative to the load impedance at the window start point is calculated, or the mean of the load impedance changes at adjacent sampling points is calculated. This mean is determined as the load impedance change caused by operator manipulation. Finally, the calculated load impedance change representing the operator manipulation change is used as input to search the power compensation table for the corresponding power compensation adjustment. Because the power compensation table is constructed based on the load impedance change from this specific source, the power compensation value required for the operator's manual adjustment can be directly obtained by using the calculated load impedance change for lookup. By calculating the load impedance change caused by the operator's manual adjustment and using this as a basis for looking up the compensation value in the table, this solution directly links the specific cause of the load impedance change with the required compensation amount, thereby improving the accuracy of power compensation.

[0159] In some specific embodiments, a power compensation table can be constructed in advance through experimental calibration. For example, in a simulated surgical scenario, by simulating different operator adjustments (such as changes in pressure and movement speed), the resulting load impedance changes are recorded, and the additional power adjustment required to maintain amplitude stability is also recorded. This data is processed to construct a mapping relationship between the load impedance change and the required power compensation adjustment, forming a power compensation table. In actual applications, a preset time window is set, such as 0.5 seconds. The system continuously collects load impedance signals within this window. Assume that a series of load impedance values are collected within a 0.5-second window, and the average change of these values relative to the window starting value is calculated to be +50Ω. The system reads a preset power compensation table, which may contain the following entries: a load impedance change of +20Ω corresponds to a compensation of +1W, +40Ω corresponds to a compensation of +2W, and +60Ω corresponds to a compensation of +3W. Through table lookup or interpolation calculation, the power compensation adjustment corresponding to a load impedance change of +50Ω may be determined to be +2.5W. This +2.5W compensation is then added to the first power adjustment calculated based on the amplitude deviation to determine the final input power adjustment. This allows the system to provide more precise power compensation for load impedance changes caused by operator technique, helping to maintain stable cutter head amplitude.

[0160] In some implementations, when the adjustment module 23 calculates the first power adjustment amount using a proportional-integral-differential algorithm based on the amplitude deviation value, the adjustment module 23 specifically performs:

[0161] Obtaining preset proportional coefficients, integral coefficients, and differential coefficients, wherein the proportional coefficients, integral coefficients, and differential coefficients are pre-calibrated according to the size of the cutting head and the type of tissue to be cut;

[0162] The proportional term is calculated based on the amplitude deviation value and the proportional coefficient, the integral term is calculated based on the integral of the amplitude deviation value and the integral coefficient, and the differential term is calculated based on the differential of the amplitude deviation value and the differential coefficient;

[0163] The proportional term, the integral term, and the differential term are added together to obtain a first power adjustment amount.

[0164] Among them, the technical solution elaborates in detail how to use the proportional-integral-differential algorithm to calculate the first power adjustment amount. First, obtain the preset proportional coefficient, integral coefficient and differential coefficient. These coefficients are the core parameters of the proportional-integral-differential controller. By pre-calibrating these coefficients according to the size of the blade and the type of cut tissue, the proportional-integral-differential controller can be optimized and adjusted for different ultrasonic knife systems. This solves the problem of poor control performance caused by coefficient mismatch when simply applying the proportional-integral-differential algorithm, and ensures the adaptability and effectiveness of the controller in different surgical environments. Then, the proportional term is calculated by multiplying the current amplitude deviation value by the proportional coefficient. The integral term is calculated by multiplying the cumulative integral of the amplitude deviation value by the integral coefficient. The differential term is calculated by multiplying the rate of change of the amplitude deviation value by the differential coefficient. Finally, the calculated proportional term, integral term and differential term are superimposed to obtain the final first power adjustment amount.

[0165] Specifically, since the control effect of the proportional-integral-differential algorithm depends on the selection of the proportional coefficient, integral coefficient and differential coefficient, if these coefficients are not properly set or adjusted according to the actual situation, it may lead to inaccurate power adjustment, slow response or excessive oscillation, and the blade amplitude cannot be effectively maintained stable, affecting the cutting performance and safety. By pre-calibrating the proportional coefficient, integral coefficient and differential coefficient according to the size of the blade and the type of cutting tissue, the proportional-integral-differential algorithm can be optimized and adjusted for different blades and cutting tissues. Therefore, according to the amplitude deviation value, these preset coefficients are used to calculate the proportional term, integral term and differential term, and they are added together to obtain the first power adjustment amount, ensuring that the first power adjustment amount calculated according to the amplitude deviation can accurately adjust the input power of the blade, thereby effectively maintaining the blade amplitude near the target value, ensuring the cutting performance and safety of the ultrasonic knife in different surgical scenarios.

[0166] In some specific embodiments, for example, when using a blade of a specific size (e.g., 5 mm in diameter) to cut liver tissue, a set of proportional coefficients, integral coefficients, and differential coefficients (e.g., Kp=10, Ki=2, Kd=0.5) are pre-calibrated for the blade size and tissue type. During the operation, the amplitude signal of the blade is acquired in real time, and the deviation value between it and the preset amplitude target value (e.g., 50 microns) is calculated. If the current amplitude deviation value is +5 microns, the proportional term is calculated as 10*5=50. At the same time, the integral term and the differential term are calculated based on the integral of the historical amplitude deviation value and the rate of change of the current amplitude deviation value, for example, the integral term is 2*(historical deviation integral) and the differential term is 0.5*(deviation change rate). These three terms are added together to obtain the first power adjustment amount.

[0167] In some embodiments, when analyzing the power adjustment parameters for maintaining the amplitude stability of the cutter head within a preset time, obtaining the power adjustment amplitude, and calculating the power adjustment rate, the adjustment module 23 specifically performs the following steps:

[0168] Read the power lookup table, which is a mapping table of control signals corresponding to power adjustment parameters and power output;

[0169] Find the corresponding power output value according to the control signal of the power adjustment parameter, and calculate the difference between the power output values at adjacent time points to obtain the power adjustment amplitude;

[0170] The ratio of the change in the power adjustment amplitude within the preset time window to the preset time interval is calculated to obtain the power adjustment rate.

[0171] In some implementations, before the step of calculating the power adjustment rate, the method further includes:

[0172] Perform filtering on the power adjustment amplitude.

[0173] Among them, the method includes reading a power lookup table, which establishes a mapping relationship between the control signal corresponding to the power adjustment parameter and the power output. By reading the table, the internal control signal can be converted into an actual power output value. Furthermore, according to the control signal of the power adjustment parameter, the corresponding power output value is found in the power lookup table. By calculating the difference between the power output values obtained at adjacent time points, the power adjustment amplitude can be obtained, which quantifies the change in power adjustment performed in a short period of time to maintain the stability of the blade amplitude. Thus, the ratio of the change in the power adjustment amplitude within a preset time window to the preset time interval is calculated to obtain the power adjustment rate, which reflects the trend of the speed of the power adjustment over time.

[0174] Specifically, to determine the source of load impedance variation, it is necessary to quantify the power adjustment behavior required to maintain blade head amplitude stability. First, a pre-stored power lookup table is read, which records the actual power output values corresponding to different control signals. For example, the control signal may be a digital quantity, while the power output is expressed in watts. Next, the control signal corresponding to the power adjustment parameter is acquired in real time. Using this control signal, the corresponding actual power output value is found in the power lookup table. A series of power output values are acquired at consecutive sampling points, and the instantaneous power adjustment amplitude is calculated by calculating the difference between the power output values at two adjacent sampling points. To obtain more stable rate information, the changes in these power adjustment amplitudes are accumulated or averaged over a preset time window (e.g., N consecutive sampling points). This change is then divided by the total duration of the time window or the sampling interval to calculate the power adjustment rate. This power adjustment rate provides quantitative information about the power adjustment trend. The calculated power adjustment amplitude and power adjustment rate, combined with the amplitude deviation rate and load impedance change rate, can be used as input data to subsequently determine the specific source of the load impedance variation, such as whether it is due to operator manipulation or differences in local tissue characteristics. By providing this quantitative power adjustment information, the cause of the load impedance change can be more accurately identified, allowing more targeted power control methods to be adopted.

[0175] In some specific embodiments, the power lookup table can be stored as a two-dimensional array, with the first column containing control signal values (e.g., integers from 0 to 255) and the second column containing corresponding power output values (e.g., from 0 to 100 W). The control signal is acquired at a sampling rate of 100 Hz. During each sampling period, the current control signal is read and the corresponding power output value is found in the lookup table. For example, if the current control signal is 150, the lookup table indicates a corresponding power of 60 W. In the next sampling period, if the control signal changes to 155, the corresponding power is 62 W. The power adjustment amplitude during this sampling interval is 62 W - 60 W = 2 W. To calculate the power adjustment rate, a preset time window of 10 sampling periods (i.e., 0.1 seconds) can be set. Within this window, the absolute values of the power adjustment amplitudes calculated for each sampling period are accumulated, for example, if the total is 15 W. The power adjustment rate can then be calculated as 15 W / 0.1 seconds = 150 W / s. The calculated power adjustment amplitude and rate are then used to determine the source of the load impedance change.

[0176] In some implementations, before calculating the power adjustment rate, the adjustment module 23 further specifically performs:

[0177] Perform filtering on the power adjustment amplitude.

[0178] Filtering the power adjustment amplitude can reduce the noise component in the power adjustment amplitude and reduce data volatility, thereby improving the reliability of subsequent power adjustment rate calculation. Filtering can be implemented using various signal processing methods, such as digital filters.

[0179] Specifically, after obtaining the power adjustment amplitude, it is input into a filter module. The filter module processes the input power adjustment amplitude data according to a preset filtering algorithm. The noise component of the processed power adjustment amplitude data is reduced and the volatility is reduced. Subsequently, the power adjustment rate is calculated using the filtered power adjustment amplitude data. The calculated power adjustment rate data has higher reliability and helps to improve the accuracy of judging the source of load impedance changes. Accurate judgment of the source of load impedance changes enables the power control system to more accurately make corresponding power adjustments based on the source of load impedance changes, thereby optimizing the performance of the ultrasonic knife.

[0180] In some specific embodiments, a sliding average filter can be used to filter the power adjustment amplitude. For example, a time window of length N is set. At each time point, the power adjustment amplitude data for the current time point and the previous N-1 time points are obtained. The average of these N power adjustment amplitude data is calculated, and this average is used as the filtered power adjustment amplitude at the current time point. This smoothes out the instantaneous spikes and random noise in the original power adjustment amplitude data, resulting in a more stable filtered data sequence. Calculating the power adjustment rate based on this stable sequence can reduce the deviation of the calculation result and improve the accuracy of the judgment.

[0181] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any actual relationship or order between these entities or operations.

[0182] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for regulating the power of an ultrasonic knife, characterized in that: Including steps: S1. Real-time acquisition of the amplitude signal and load impedance signal of the cutter head; S2. Determine the source of the load impedance change based on the amplitude signal and the load impedance signal; S3. Adjust the input power of the cutting head according to the source of the load impedance change.

2. The ultrasonic knife power control method according to claim 1, characterized in that: Step S2 includes: Comparing the amplitude signal with a preset amplitude target value to obtain an amplitude deviation value, and calculating an amplitude deviation rate; Analyze the power adjustment parameters to maintain the amplitude stability of the cutter head within a preset time, obtain the power adjustment amplitude, and calculate the power adjustment rate; monitoring the load impedance signal, obtaining a load impedance change, and calculating a load impedance change rate; The source of the load impedance change is determined according to the amplitude deviation rate, the load impedance change rate, and the power adjustment rate.

3. The ultrasonic knife power control method according to claim 2, characterized in that: The step of determining a source of a load impedance change according to the amplitude deviation rate, the load impedance change rate, and the power adjustment rate comprises: If the load impedance change rate is greater than a preset first threshold, the amplitude deviation rate is less than a preset second threshold, and the power adjustment rate is greater than a preset third threshold, it is determined that the source of the load impedance change is operator manipulation adjustment; otherwise, it is determined that the source of the load impedance change is a difference in local tissue characteristics.

4. The ultrasonic knife power control method according to claim 3, characterized in that: Step S3 includes: Calculating a first power adjustment amount according to the amplitude signal and the preset amplitude target value; If it is determined that the source of the load impedance change is caused by a difference in local tissue characteristics, adjusting the input power of the cutting head according to the first power adjustment amount; If it is determined that the source of the load impedance change is caused by operator manual adjustment, a power compensation adjustment amount is obtained from a preset power compensation table based on the amplitude signal, and the power compensation adjustment amount is added to the first power adjustment amount to adjust the input power of the cutter head.

5. The ultrasonic knife power control method according to claim 4, characterized in that: The step of calculating the first power adjustment amount according to the amplitude signal and the preset amplitude target value includes: Calculating an amplitude deviation value based on the amplitude signal and the preset amplitude target value; A first power adjustment amount is calculated according to the amplitude deviation value using a proportional-integral-differential algorithm.

6. The ultrasonic knife power control method according to claim 4, characterized in that: The step of obtaining the power compensation adjustment amount from a preset power compensation table according to the amplitude signal includes: Reading a power compensation table; the power compensation table is obtained by pre-building a mapping relationship between the load impedance change caused by the operator's manual adjustment and the power compensation adjustment amount; Acquiring a plurality of load impedance signals within a preset time window; Calculating an average of the load impedance variation according to the plurality of load impedance signals as the load impedance variation caused by the operator's manual adjustment; According to the load impedance change caused by the operator's manual adjustment and the power compensation table, a corresponding power compensation adjustment amount is obtained.

7. The ultrasonic knife power control method according to claim 5, characterized in that: The step of calculating the first power adjustment amount by using a proportional-integral-differential algorithm according to the amplitude deviation value includes: Obtaining preset proportional coefficients, integral coefficients, and differential coefficients, wherein the proportional coefficients, integral coefficients, and differential coefficients are pre-calibrated according to the size of the cutting head and the type of tissue to be cut; Calculating a proportional term according to the amplitude deviation value and the proportional coefficient, calculating an integral term according to the integral of the amplitude deviation value and the integral coefficient, and calculating a differential term according to the differential of the amplitude deviation value and the differential coefficient; The proportional term, the integral term, and the differential term are added together to obtain the first power adjustment amount.

8. The ultrasonic knife power control method according to claim 2, characterized in that: The steps of analyzing the power adjustment parameter for maintaining the amplitude stability of the cutter head within a preset time, obtaining the power adjustment amplitude, and calculating the power adjustment rate include: Read the power lookup table, which is a mapping table of control signals corresponding to power adjustment parameters and power output; Searching for a corresponding power output value according to the control signal of the power adjustment parameter, and calculating the difference between the power output values at adjacent time points to obtain a power adjustment amplitude; The ratio of the change in the power adjustment amplitude within the preset time window to the preset time interval is calculated to obtain the power adjustment rate.

9. The ultrasonic knife power control method according to claim 8, characterized in that: Before calculating the power adjustment rate step, the method further includes: The power adjustment amplitude is filtered.

10. An ultrasonic knife power control system, characterized in that: include: An acquisition module is used to obtain the amplitude signal and load impedance signal of the cutter head in real time; a determination module, configured to determine a source of a load impedance change based on the amplitude signal and the load impedance signal; The adjustment module is used to adjust the input power of the cutting head according to the source of the load impedance change.

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