A method and system for controlling the power of an ultrasonic scalpel

Abstract

This application provides a method and system for controlling the power of an ultrasonic scalpel, relating to the field of ultrasonic scalpel technology. By determining the source of load impedance changes and adjusting the input power of the scalpel head accordingly, the stability of the scalpel head's working performance is ensured, the cutting effect is optimized, and tissue damage is reduced.

Description

Technical Field

[0001] This application relates to the field of ultrasonic scalpel technology, and more specifically, to an ultrasonic scalpel power control method and system. Background Technology

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

[0003] Meanwhile, surgical procedures are typically performed by human operators who guide the ultrasonic scalpel tip through techniques such as holding the handle, applying downward pressure, and adjusting the cutting angle and speed. These techniques also alter the interaction between the scalpel tip and the tissue, thus 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 scalpel tip and the tissue, leading to an increase in load impedance; rapid movement of the scalpel tip by the operator can also cause rapid changes in load.

[0004] To achieve adaptive power control of ultrasonic scalpels, enabling them to adjust the input power of the scalpel head according to the actual load conditions to maintain stable cutting performance and reduce tissue damage, 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 for 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 scalpel power control method and system, which determines the source of load impedance change and adjusts the input power accordingly to maintain stable scalpel head performance, optimize cutting effect, and reduce tissue damage.

[0007] This application provides a method for controlling the power of an ultrasonic scalpel, including the following steps:

[0008] S1. Real-time acquisition of the amplitude signal and load impedance signal of the cutting 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] By using the above settings and adopting different adjustment methods for load impedance changes from different sources, the power adjustment can be made more targeted, ensuring the stability of the cutter head's working performance, optimizing the cutting effect, and reducing tissue damage.

[0012] Optionally, step S2 includes:

[0013] The amplitude signal is compared with the preset amplitude target value to obtain the amplitude deviation value, and the amplitude deviation rate is calculated.

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

[0015] Monitor the load impedance signal, obtain the load impedance change, and calculate the load impedance change rate;

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

[0017] By setting the above parameters, we can more accurately distinguish the specific reasons for the changes in load impedance, providing a basis for subsequent targeted power adjustments, thereby ensuring the cutting performance of the cutter head.

[0018] Optionally, the step of determining the source of load impedance change based on 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, then the source of the load impedance change is determined to be operator manual adjustment; otherwise, the source of the load impedance change is determined to be tissue local characteristic difference.

[0020] By setting clear judgment rules, it is possible to distinguish between two main sources of load impedance change, providing a basis for subsequent power adjustments to be made for different sources, thus improving the effectiveness of power regulation.

[0021] Optionally, step S3 includes:

[0022] The first power adjustment amount is calculated based on the amplitude signal and the preset amplitude target value;

[0023] If it is determined that the change in load impedance is caused by differences in local tissue characteristics, then the input power of the blade is adjusted according to the first power adjustment amount;

[0024] If it is determined that the change in load impedance is caused by the operator's manual adjustment, then based on the amplitude signal, the power compensation adjustment amount is obtained from the preset power compensation table, 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 based on the amplitude signal and the preset amplitude target value includes:

[0026] The amplitude deviation value is calculated based on the amplitude signal and the preset amplitude target value;

[0027] Based on the amplitude deviation value, the first power adjustment amount is calculated using a proportional-integral-differential algorithm.

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

[0029] Read the power compensation table; the power compensation table is obtained by pre-constructing a mapping relationship between the load impedance change caused by operator adjustment and the power compensation adjustment amount;

[0030] Acquire multiple load impedance signals within a preset time window;

[0031] The average value of the load impedance change is calculated based on multiple load impedance signals, and used as the load impedance change caused by operator adjustment.

[0032] Based on the change in load impedance caused by the operator's adjustment and the power compensation table, obtain the corresponding power compensation adjustment amount.

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

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

[0035] The proportional term is calculated based on the amplitude deviation value and the proportionality 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 derivative of the amplitude deviation value and the differential coefficient.

[0036] The first power adjustment amount is obtained by adding the proportional term, the integral term, and the differential term.

[0037] Optionally, the step of analyzing the power adjustment parameters that maintain the amplitude stability of the cutter head within a preset time, obtaining the power adjustment amplitude, and calculating the power adjustment rate includes:

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

[0039] The corresponding power output value is found based on the control signal of the power adjustment parameter, and the difference between the power output values ​​at adjacent time points is calculated to obtain the power adjustment amplitude.

[0040] The power adjustment rate is obtained by calculating the ratio of the change in power adjustment amplitude within a preset time window to a preset time interval.

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

[0042] The power adjustment amplitude is filtered.

[0043] Secondly, this application provides an ultrasonic scalpel power control system, comprising:

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

[0045] The judgment module is used to determine the source of the load impedance change based on the amplitude signal and the load impedance signal;

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

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

[0048] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0049] Figure 1 This is a flowchart of an ultrasonic scalpel power control method provided in an embodiment of this application.

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

[0051] Labeling explanations: 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 Implementation

[0052] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0053] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0054] Please refer to Figures 1-2 This application provides an ultrasonic scalpel power control method and system. By determining the source of load impedance change and adjusting the input power of the scalpel head accordingly, the stability of the scalpel head's working performance is ensured, the cutting effect is optimized, and tissue damage is reduced.

[0055] This application provides a method for controlling the power of an ultrasonic scalpel, including the following steps:

[0056] S1. Real-time acquisition of the amplitude signal and load impedance signal of the cutting 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 tool head according to the source of the load impedance change.

[0059] The process involves real-time acquisition of the blade's amplitude and load impedance signals, providing fundamental data for subsequent judgment and adjustment. The amplitude signal reflects the blade's working state, while the load impedance signal reflects the load condition resulting from the interaction between the blade and the tissue. Based on the acquired amplitude and load impedance signals, the characteristics of these signal changes are analyzed to identify the specific causes of load impedance variations. Load impedance variations may be caused by differences in local tissue characteristics or by operator adjustments; accurately identifying the cause of load impedance variations is a prerequisite for power regulation. Based on the identified source of load impedance variation, 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 issue 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 the power accordingly. By employing different adjustment methods for load impedance changes from different sources, the power adjustment becomes more targeted, ensuring the stability of the scalpel's performance, optimizing cutting results, and reducing tissue damage.

[0061] In practical applications, ultrasonic scalpels are equipped with sensors to monitor the amplitude and load impedance signals of the scalpel head in real time. These signals are then analyzed to determine whether the current change in load impedance is caused by a change in the characteristics of the tissue contacted by the scalpel head, or by changes in the operator's applied pressure, speed, or angle. Once the source of the load impedance change is determined, the processing unit sends a command to the power output unit according to preset control logic. If it is determined to be a change in tissue characteristics, the first power adjustment of the scalpel head's input power is used; if it is determined to be an adjustment by the operator's technique, the second power adjustment of the scalpel head's input power is used. The scalpel head's input power is then adjusted according to either the first or second power adjustment to cope with the change in load impedance and maintain the scalpel head's working state.

[0062] In some implementations, step S2 includes:

[0063] The amplitude signal is compared with the preset amplitude target value to obtain the amplitude deviation value, and the amplitude deviation rate is calculated.

[0064] Analyze the power adjustment parameters that maintain the stable amplitude of the cutter head within a 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] The source of load impedance change can be determined based on the amplitude deviation rate, load impedance change rate, and power adjustment rate.

[0067] Specifically, firstly, the amplitude and load impedance signals of the cutting head are acquired in real time. Next, the amplitude deviation is calculated based on the amplitude signal and the preset target amplitude value, and the amplitude deviation rate is calculated to quantify the degree and speed of amplitude deviation from the target. Simultaneously, the power adjustment parameters that maintain the cutting head's amplitude stability within a preset time are analyzed to obtain the power adjustment amplitude and calculate the power adjustment rate, reflecting the intensity and speed of power adjustment performed to maintain amplitude stability. Furthermore, the load impedance signal is monitored to obtain the load impedance change and calculate the load impedance change rate, directly quantifying the degree and speed of load impedance change. Therefore, a comprehensive judgment is made by combining these three dynamic parameters: amplitude deviation rate, load impedance change rate, and 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 amplitude stability has been effectively maintained through large-scale power adjustment, which may correspond to dynamic load impedance changes caused by operator technique. Conversely, if the load impedance change is accompanied by a high amplitude deviation rate, even if the system has adjusted the power, the amplitude still has a large deviation, which may indicate that the load impedance change originates from differences in local tissue characteristics. By quantifying and comprehensively analyzing these parameters, this method can more accurately distinguish the specific reasons for changes in load impedance, providing a basis for subsequent targeted power adjustments, thereby ensuring the cutting performance of the cutter head.

[0068] In some implementations, the step of determining the source of load impedance change based on amplitude deviation rate, load impedance change rate, and 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 the load impedance change is determined to be caused by operator technique adjustment; otherwise, the load impedance change is determined to be caused by differences in local tissue characteristics.

[0070] Specifically, this scheme 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 parameters are then compared to preset first, second, and third thresholds, respectively. If the load impedance change rate exceeds the first threshold, while the amplitude deviation rate is lower than the second threshold, and the power adjustment rate exceeds the third threshold, the current load impedance change is determined to be caused by operator manipulation. This combination typically corresponds to a sudden application of pressure by the operator, leading to a rapid increase in load, followed by a significant power adjustment to maintain stable blade amplitude. 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 may exhibit different patterns, such as a load impedance change rate lower than the first threshold (i.e., relatively slow change), or a large amplitude deviation after power adjustment. These situations differ from the typical response pattern caused by operator manipulation. Therefore, by setting clear judgment rules, two main sources of load impedance change can be distinguished, providing a basis for subsequent power adjustments based on different sources and improving the effectiveness of power control.

[0071] The specific value of the preset first threshold can be determined experimentally: under typical operating techniques (such as rapid movement and angle adjustment), record the rate of change of load impedance, and take the data value in which 95% of the collected data values ​​are lower than this threshold as the preset first threshold; at the same time, verify that the preset threshold is significantly higher than the rate of change of impedance caused by differences in tissue characteristics (such as the maximum rate of change when cutting dense tissue).

[0072] The second threshold needs to be determined through cutting experiments: under the premise of maintaining cutting efficiency and the decrease in cutting efficiency not exceeding 10%, the amplitude deviation rate under different operating techniques (such as moving speed) and tissue types (such as liver, fascia) is measured, and the maximum allowable value is taken as the threshold (such as 5%).

[0073] The preset third threshold is the power adjustment rate (unit: W / s), which needs to be calibrated according to the performance of the ultrasonic scalpel's power module: measure the time required for the power supply to rise from the minimum power to the maximum power, calculate the maximum allowable rate (e.g., 200W / s), and reserve a 20% safety margin (e.g., set the threshold to 160W / s).

[0074] In practical applications, for example, a first threshold might be set to 5% / ms, a second threshold to 3%, and a third threshold to 2W / ms. For instance, if at a certain moment, the load impedance is detected to change from 100Ω to 130Ω within 5ms, the calculated load impedance change rate is 6% / ms. Simultaneously, the target value of the tool head amplitude is 50μm, and the actual amplitude remains between 49.5μm and 50.5μm within the same time period (5ms), the calculated amplitude deviation rate is 1%. Furthermore, the power output is adjusted from 30W to 45W within the same time period (5ms), the calculated power adjustment rate is 3W / ms. Since 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 simultaneously. Therefore, it is determined that the load impedance change originates from operator manual adjustment. In another case, if the load impedance changes from 100Ω to 110Ω within 5ms, the calculated load impedance change rate is 2% / ms. Even if the amplitude deviation rate and 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), the source of the load impedance change is determined to be the difference in local tissue characteristics.

[0075] In some implementations, step S3 includes:

[0076] The first power adjustment amount is calculated based on the amplitude signal and the preset amplitude target value;

[0077] If the change in load impedance is determined to be caused by differences in local tissue characteristics, then the input power of the cutting head is adjusted according to the first power adjustment amount.

[0078] If the change in load impedance is determined to be caused by the operator's manual adjustment, then the power compensation adjustment amount is obtained from the preset power compensation table based on the amplitude signal. The power compensation adjustment amount is then added to the first power adjustment amount to adjust the input power of the cutter head.

[0079] The core of this scheme lies in adjusting the input power of the cutting head based on the source of the load impedance change. First, the real-time amplitude signal of the cutting head is continuously monitored and compared with a preset amplitude target value to calculate a basic power adjustment amount, i.e., the first power adjustment amount, reflecting the amplitude deviation. This first power adjustment amount aims to correct amplitude deviations from the target value by changing the input power. When the system determines that the load impedance change is caused by the cutting head contacting different tissue characteristics, it directly uses the calculated first power adjustment amount to adjust the input power of the cutting head to maintain amplitude stability. When the system determines that the load impedance change is caused by operator-applied pressure, angle, or speed adjustments, in addition to using the first power adjustment amount, it also consults a pre-built power compensation table based on the current amplitude signal to obtain an additional power compensation adjustment amount. This compensation amount reflects the additional power required under the load conditions caused by the specific operating technique. Finally, the first power adjustment amount and the power compensation adjustment amount are superimposed to form the total power adjustment amount, which is used to adjust the input power of the cutting head. In this way, the system can more accurately respond to load impedance changes from different sources, improving the adaptability of power control.

[0080] Specifically, this technical solution addresses the problem that a single power adjustment strategy cannot effectively handle load impedance changes from different sources. First, it acquires the real-time amplitude signal of the cutting head and a preset target amplitude value, calculates the deviation between them, and calculates a first power adjustment amount based on this deviation. This first power adjustment amount is the foundation for maintaining amplitude stability. Then, different power adjustment logics are executed based on the source of the load impedance change determined in the previous steps. If the load impedance change is determined to originate from differences in local tissue characteristics, indicating that the load impedance change is caused by the tissue's inherent properties, the calculated first power adjustment amount is directly used to adjust the cutting head's input power, thereby reducing the impact of tissue characteristic changes on the cutting head's amplitude. If the load impedance change is determined to originate from operator manipulation, indicating that the load impedance change is caused by the operator's active behavior, in addition to using the first power adjustment amount, it is also necessary to look up the corresponding power compensation adjustment amount 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 found power compensation adjustment amount is added to the first power adjustment amount to obtain the final power adjustment amount, which is then used to adjust the cutting head's input power. This superimposed adjustment method allows the system to provide more targeted compensation when dealing with dynamic load impedance changes caused by operator manipulation, thereby more effectively maintaining amplitude stability or achieving the desired surgical outcome. Thus, by differentiating the sources of load impedance changes and employing corresponding adjustment methods, the accuracy and effectiveness of power regulation are improved.

[0081] In practical applications, assume a preset amplitude target value of 50μm. The system acquires the tool head amplitude signal in real time, for example, the current amplitude is 45μm. The calculated amplitude deviation is -5μm. Based on this deviation, a first power adjustment is calculated using a proportional-integral-differential algorithm, for example, +10W. Simultaneously, the system determines that the load impedance change is caused by operator manipulation. At this point, the system consults a preset power compensation table based on the current amplitude signal (45W) or the load impedance change related to operator manipulation. This power compensation table may store additional compensation required when the amplitude is low and the load increases due to operator manipulation. For example, the table shows a power compensation adjustment of +5W. Finally, the first power adjustment (+10W) is added to the power compensation adjustment (+5W), resulting in a total power adjustment of +15W. The input power to the tool head is increased by 15W. If the change in load impedance is determined to be caused by differences in local tissue characteristics, the input power of the cutting head is adjusted only by the first power adjustment amount (+10W), increasing the input power by 10W. In this way, the system provides additional power compensation for load impedance changes caused by operator technique, thus more effectively maintaining amplitude stability.

[0082] In some implementations, the step of calculating the first power adjustment amount based on the amplitude signal and a 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 that the cutter head is expected to maintain).

[0084] Based on the amplitude deviation value, the first power adjustment amount is calculated using the proportional-integral-differential algorithm.

[0085] The method for calculating the first power adjustment amount based on the amplitude signal and the preset amplitude target value first acquires the current amplitude signal of the cutter head. The real-time acquired amplitude signal 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 to a proportional-integral-derivative (PID) algorithm (e.g., using a PID controller). The PID controller calculates an output value, the first power adjustment amount, based on the amplitude deviation value and its change over time. This first power adjustment amount is used to subsequently adjust the input power of the cutter head. The PID algorithm combines proportional, integral, and derivative control methods: proportional adjustment based on the current deviation, integral adjustment to eliminate steady-state error, and derivative adjustment to predict the trend of deviation changes. Through this combination, the first power adjustment amount used for power adjustment is calculated.

[0086] Specifically, to address the issues of insufficient control accuracy, slow response, or system oscillation that may result from simply calculating the power adjustment, this solution employs a proportional-integral-derivative (PID) algorithm to calculate the first power adjustment. First, the amplitude signal of the cutting head is acquired in real time and compared with a 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. Then, this amplitude deviation value is input to the PID controller. The PID controller calculates the proportional, integral, and derivative terms based on preset proportional coefficients (Kp), integral coefficients (Ki), and derivative coefficients (Kd). The proportional term is proportional to the current amplitude deviation; the integral term is proportional to the cumulative amplitude deviation over time (integral); and the derivative term is proportional to the rate of change of the amplitude deviation over time (derivative). These three calculated terms are then added together to obtain the final first power adjustment. For example, the first power adjustment = Kp * (current deviation) + Ki * (integral of deviation) + Kd * (derivative of deviation). This calculated initial power adjustment is then used to adjust the input power of the tool head to reduce amplitude deviation and maintain the tool head amplitude at a preset target value. Using a PID algorithm for calculation comprehensively considers current deviation, historical deviation, and deviation trends, thus calculating a more reasonable and stable initial power adjustment, which helps maintain the stability of the tool head amplitude.

[0087] In some specific implementations, calculating the first power adjustment based on the amplitude signal and the preset amplitude target value can be achieved as follows: The system acquires the amplitude signal of the cutting head in real time, for example, once every 1 millisecond. The preset amplitude target value is set to 55 micrometers. At a certain moment, the acquired amplitude signal is 53 micrometers. The amplitude deviation value is calculated as: 53 micrometers - 55 micrometers = -2 micrometers. This deviation value is input into the PID controller. The parameters of the PID controller are preset as follows: proportional coefficient Kp = 10, integral coefficient Ki = 5, and derivative coefficient Kd = 2. The controller calculates the proportional term: 10 * (-2) = -20. At the same time, the controller accumulates historical deviations to calculate the integral term and calculates the rate of change of the current deviation to calculate the derivative term. Assuming that after calculation, the integral term is -5 and the derivative term is -4, the calculated first power adjustment is: -20 + (-5) + (-4) = -29. This -29 is the suggested power adjustment, indicating that the power needs to be reduced. This calculation process continues, dynamically calculating the power adjustment amount based on the real-time amplitude deviation and applying it to the power output control circuit of the ultrasonic scalpel, thereby driving the scalpel head amplitude to approach and maintain stability towards the target value of 55 micrometers.

[0088] In some implementations, the step of obtaining the power compensation adjustment amount from a preset power compensation table based on the amplitude signal includes:

[0089] Read the power compensation table; the power compensation table is obtained by pre-constructing a mapping relationship between the load impedance change caused by operator adjustment and the power compensation adjustment amount;

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

[0091] The average value of the load impedance change is calculated based on multiple load impedance signals, and this value is used as the load impedance change caused by the operator's manual adjustment.

[0092] Based on the change in load impedance caused by the operator's adjustment and the power compensation table, obtain the corresponding power compensation adjustment amount.

[0093] The power compensation table provides the foundational data for compensation lookup. This table is derived by pre-establishing a mapping between load impedance changes caused by operator adjustments and the corresponding power compensation adjustments. Multiple load impedance signals within a preset time window are acquired, providing data samples for calculating load impedance changes. The average load impedance change is calculated from these signals, yielding a representative value for the load impedance change caused by operator adjustments. This averaging process smooths signal fluctuations and more stably reflects the average load impedance change caused by operator adjustments over a period, improving the stability of the input used to find the compensation amount. Based on the load impedance change caused by operator adjustments and the power compensation table, the corresponding power compensation adjustment is obtained. Using the calculated load impedance change for lookup, the required power compensation value for the operator's adjustments can be directly obtained, improving the targeting of power compensation.

[0094] Specifically, this scheme provides a method for obtaining the power compensation adjustment amount, used to adjust the input power of the tool head when the source of the load impedance change is determined to be due to operator manipulation. First, a pre-built power compensation table is read, which establishes the correspondence between the load impedance change caused by operator manipulation and the required power compensation adjustment amount. 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 100Hz within a 1-second time window. Then, based on the acquired load impedance signals, the average value of the load impedance change is calculated; for example, the average value of the change in load impedance at each sampling point relative to the load impedance at the beginning of the window is calculated, or the average value of the change in load impedance at adjacent sampling points is calculated. This average value is determined as the load impedance change caused by operator manipulation. Finally, the calculated representative load impedance change caused by operator manipulation is used as input to look up the corresponding power compensation adjustment amount in the power compensation table. Since the power compensation table is constructed based on the load impedance change from this specific source, the calculated load impedance change can be used to directly obtain the power compensation value required for operator adjustments. This scheme directly links the specific cause of the load impedance change with the required compensation amount by calculating the load impedance change caused by operator adjustments and using this as a basis to look up the compensation value in the table, thus improving the accuracy of power compensation.

[0095] In some specific implementations, the power compensation table can be pre-calibrated experimentally. For example, in a simulated surgical scenario, by simulating different operator techniques (such as changes in pressure and movement speed), the resulting changes in load impedance are recorded, along with the additional power adjustment required to maintain amplitude stability. These data are processed to establish a mapping between the changes in load impedance and the required power compensation adjustment, forming the power compensation table. In practical applications, a preset time window is set, such as 0.5 seconds. The system continuously acquires load impedance signals within this window. Assuming that a series of load impedance values ​​are acquired within a 0.5-second window, the average change of these values ​​relative to the initial value of the window is calculated to be +50Ω. The system reads the preset power compensation table, which may contain entries such as: 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, 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, together determining the final input power adjustment value. Therefore, the system can provide more accurate power compensation for load impedance changes caused by operator technique, helping to maintain stable tool head amplitude.

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

[0097] Obtain the preset proportional coefficient, integral coefficient, and differential coefficient, which are pre-calibrated according to the size of the cutting head and the type of tissue being cut;

[0098] Calculate the proportional term based on the amplitude deviation value and the proportionality coefficient; calculate the integral term based on the integral of the amplitude deviation value and the integral coefficient; calculate the differential term based on the differential of the amplitude deviation value and the differential coefficient.

[0099] Adding the proportional, integral, and derivative terms together yields the first power adjustment.

[0100] This technical solution details how to calculate the first power adjustment using a proportional-integral-derivative (PID) algorithm. First, preset proportional, integral, and derivative coefficients are obtained. These coefficients are the core parameters of the PID controller. By pre-calibrating these coefficients according to the size of the blade and the type of tissue being cut, the PID controller can be optimized for different ultrasonic scalpel systems. This solves the problem of poor control performance caused by coefficient mismatch when simply applying the PID algorithm, ensuring the adaptability and effectiveness of the controller in different surgical environments. Next, 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 derivative term is calculated by multiplying the rate of change of the amplitude deviation value by the derivative coefficient. Finally, the calculated proportional, integral, and derivative terms are superimposed to obtain the final first power adjustment.

[0101] Specifically, since the control effect of the proportional-integral-derivative (PID) algorithm depends on the selection of proportional, integral, and derivative coefficients, 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, failing to effectively maintain the stability of the cutter head amplitude and affecting cutting performance and safety. By pre-calibrating the proportional, integral, and derivative coefficients according to the cutter head size and the type of tissue being cut, the PID algorithm can be optimized for different cutter heads and tissues. Therefore, based on the amplitude deviation value, the proportional, integral, and derivative terms are calculated using these preset coefficients, and they are added together to obtain the first power adjustment amount. This ensures that the first power adjustment amount calculated based on the amplitude deviation can accurately adjust the input power of the cutter head, thereby effectively maintaining the cutter head amplitude near the target value and guaranteeing the cutting performance and safety of the ultrasonic scalpel in different surgical scenarios.

[0102] In some specific implementations, for example, when cutting liver tissue using a blade of a specific size (e.g., 5 mm in diameter), a set of proportional, integral, and differential coefficients (e.g., Kp = 10, Ki = 2, Kd = 0.5) are pre-calibrated for the blade size and tissue type. During the surgery, the amplitude signal of the blade is acquired in real time, and its deviation from the preset amplitude target value (e.g., 50 micrometers) is calculated. If the current amplitude deviation is +5 micrometers, the proportional term is calculated as 10 * 5 = 50. Simultaneously, based on the integral of the historical amplitude deviation value and the rate of change of the current amplitude deviation value, integral and differential terms are calculated respectively; 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 implementations, the steps of analyzing the power adjustment parameters that maintain the stability of the cutter head's amplitude within a preset time, obtaining the power adjustment amplitude, and calculating the power adjustment rate include:

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

[0105] The corresponding power output value is found based on the control signal of the power adjustment parameter, and the difference between the power output values ​​at adjacent time points is calculated to obtain the power adjustment amplitude.

[0106] The power adjustment rate is obtained by calculating the ratio of the change in power adjustment amplitude within a preset time window to a preset time interval.

[0107] In some implementations, the method further includes the following steps prior to calculating the power adjustment rate:

[0108] The power adjustment amplitude is filtered.

[0109] 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 this table, the internal control signal can be converted into the actual power output value. Further, based on the control signal of the power adjustment parameter, the corresponding power output value is looked up 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. This amplitude quantifies the amount of power adjustment made to maintain the stability of the cutter head amplitude within a short period. Therefore, the ratio of the change in power adjustment amplitude within a preset time window to a preset time interval is calculated to obtain the power adjustment rate, which reflects the speed of power adjustment change over time.

[0110] Specifically, to determine the source of load impedance changes, it is necessary to quantify the power adjustment behavior used to maintain stable blade amplitude. 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 might be a digital quantity, while the power output is a wattage value. Then, the control signal corresponding to the power adjustment parameters is acquired in real time. Using this control signal, the corresponding actual power output value is found in the power lookup table. At consecutive sampling time points, a series of power output values ​​are acquired, and the instantaneous power adjustment amplitude is obtained 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 within a preset time window (e.g., N consecutive sampling points), and this change is 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 for subsequent determination of the specific source of load impedance changes, such as whether it is due to operator technique adjustments or differences in local tissue characteristics. By providing this quantified power adjustment information, the causes of load impedance changes can be identified more accurately, enabling more targeted power regulation.

[0111] In some implementations, the power lookup table can be stored as a two-dimensional array, with the first column representing the control signal value (e.g., an integer from 0 to 255) and the second column representing the corresponding power output value (e.g., 0 to 100W). The control signal is acquired at a sampling rate of 100Hz. In 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 shows a corresponding power of 60W. In the next sampling period, if the control signal changes to 155, the corresponding power is 62W, then the power adjustment amplitude within that sampling interval is 62W - 60W = 2W. 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 sum of the absolute values ​​of the power adjustment amplitude calculated for each sampling period is accumulated, for example, a sum of 15W. The power adjustment rate can then be calculated as 15W / 0.1 seconds = 150W / s. This calculated power adjustment amplitude and rate are then used to determine the source of the load impedance change.

[0112] In some implementations, the method further includes the following steps prior to calculating the power adjustment rate:

[0113] The power adjustment amplitude is filtered.

[0114] Filtering the power adjustment amplitude can reduce noise components and data fluctuations, thereby improving the reliability of subsequent power adjustment rate calculations. This filtering process can be implemented using various signal processing methods, such as digital filters.

[0115] Specifically, after acquiring the power adjustment amplitude, it is input into a filter module. This filter module processes the input power adjustment amplitude data according to a preset filtering algorithm. The processed power adjustment amplitude data has reduced noise components and decreased fluctuations. Subsequently, the power adjustment rate is calculated using the filtered power adjustment amplitude data. The calculated power adjustment rate data has higher reliability, which helps improve the accuracy of determining the source of load impedance changes. Accurate determination of the source of load impedance changes enables the power control system to more precisely adjust the power according to the source of load impedance changes, optimizing the performance of the ultrasonic scalpel.

[0116] In some specific implementations, a moving average filter can be used to filter the power adjustment amplitude. For example, a time window of length N can be set. At each time point, the power adjustment amplitude data of the current time point and the previous N-1 time points are acquired. The average of these N power adjustment amplitude data points is calculated, and this average is used as the filtered power adjustment amplitude of the current time point. This smooths 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 results and improve the accuracy of the judgment.

[0117] Secondly, this application provides an ultrasonic scalpel power control system, comprising:

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

[0119] The judgment module 22 is used to determine the source of the load impedance change based on the amplitude signal and the load impedance signal;

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

[0121] Please refer to Figure 2The acquisition module 21 is connected to the blade head and is used to acquire amplitude signals reflecting the blade head's motion state and load impedance signals reflecting the interaction between the blade head and tissue. The acquisition module 21 may include a sensor and a signal acquisition circuit. The judgment module 22 receives the amplitude signal and load impedance signal output by the acquisition module 21 and performs analysis to distinguish the specific reasons for the load impedance change. The judgment module 22 may be implemented by a first processor executing a specific algorithm. The adjustment module 23 receives the judgment result from the judgment module 22 and the signal from 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 blade head's drive circuit to change the input power of the blade head. The adjustment module 23 may be implemented by a second processor and a PID control circuit. Thus, the ultrasonic scalpel power control system achieves adaptive control of the ultrasonic scalpel's input power through the coordinated work of each module. 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 surgery, the ultrasonic scalpel tip comes into contact with biological tissue. Differences in local tissue characteristics or operator adjustments can cause changes in load impedance. To maintain stable tip performance, targeted power adjustments are needed based on the source of the load impedance change. The ultrasonic scalpel power control system monitors the tip's amplitude and load impedance in real time via module 21, inputting these signals to judgment module 22. Judgment module 22 analyzes these signals to identify whether the load impedance change is caused by local tissue characteristics or operator adjustments. If it is determined to be a tissue characteristic change, adjustment module 23 may calculate a power adjustment based on the amplitude deviation to maintain amplitude stability. If it is determined to be an operator adjustment, adjustment module 23 may add an additional power compensation adjustment on top of maintaining amplitude stability to address the load impedance change caused by the operator. Adjustment module 23 converts the calculated power adjustment into a control signal, which is applied to the ultrasonic scalpel's power output unit to adjust the tip's input power. Therefore, the ultrasonic scalpel power control system can distinguish the source of load impedance change 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 scalpel head and reduces tissue damage.

[0123] The process involves real-time acquisition of the blade's amplitude and load impedance signals, providing fundamental data for subsequent judgment and adjustment. The amplitude signal reflects the blade's working state, while the load impedance signal reflects the load condition resulting from the interaction between the blade and the tissue. Based on the acquired amplitude and load impedance signals, the characteristics of these signal changes are analyzed to identify the specific causes of load impedance variations. Load impedance variations may be caused by differences in local tissue characteristics or by operator adjustments; accurately identifying the cause of load impedance variations is a prerequisite for power regulation. Based on the identified source of load impedance variation, 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 issue 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 the power accordingly. By employing different adjustment methods for load impedance changes from different sources, the power adjustment becomes more targeted, ensuring the stability of the scalpel's performance, optimizing cutting results, and reducing tissue damage.

[0125] In practical applications, ultrasonic scalpels are equipped with sensors to monitor the amplitude and load impedance signals of the scalpel head in real time. These signals are then analyzed to determine whether the current change in load impedance is caused by a change in the characteristics of the tissue contacted by the scalpel head, or by changes in the operator's applied pressure, speed, or angle. Once the source of the load impedance change is determined, the processing unit sends a command to the power output unit according to preset control logic. If it is determined to be a change in tissue characteristics, the first power adjustment of the scalpel head's input power is used; if it is determined to be an adjustment by the operator's technique, the second power adjustment of the scalpel head's input power is used. The scalpel head's input power is then adjusted according to either the first or second power adjustment to cope with the change in load impedance and maintain the scalpel head's working state.

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

[0127] The amplitude signal is compared with the preset amplitude target value to obtain the amplitude deviation value, and the amplitude deviation rate is calculated.

[0128] Analyze the power adjustment parameters that maintain the stable amplitude of the cutter head within a 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] The source of load impedance change can be determined based on the amplitude deviation rate, load impedance change rate, and power adjustment rate.

[0131] Specifically, firstly, the amplitude and load impedance signals of the cutting head are acquired in real time. Next, the amplitude deviation is calculated based on the amplitude signal and the preset target amplitude value, and the amplitude deviation rate is calculated to quantify the degree and speed of amplitude deviation from the target. Simultaneously, the power adjustment parameters that maintain the cutting head's amplitude stability within a preset time are analyzed to obtain the power adjustment amplitude and calculate the power adjustment rate, reflecting the intensity and speed of power adjustment performed to maintain amplitude stability. Furthermore, the load impedance signal is monitored to obtain the load impedance change and calculate the load impedance change rate, directly quantifying the degree and speed of load impedance change. Therefore, a comprehensive judgment is made by combining these three dynamic parameters: amplitude deviation rate, load impedance change rate, and 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 amplitude stability has been effectively maintained through large-scale power adjustment, which may correspond to dynamic load impedance changes caused by operator technique. Conversely, if the load impedance change is accompanied by a high amplitude deviation rate, even if the system has adjusted the power, the amplitude still has a large deviation, which may indicate that the load impedance change originates from differences in local tissue characteristics. By quantifying and comprehensively analyzing these parameters, this method can more accurately distinguish the specific reasons for changes in load impedance, providing a basis for subsequent targeted power adjustments, thereby ensuring the cutting performance of the cutter head.

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

[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 the load impedance change is determined to be caused by operator technique adjustment; otherwise, the load impedance change is determined to be caused by differences in local tissue characteristics.

[0134] Specifically, this scheme 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 parameters are then compared to preset first, second, and third thresholds, respectively. If the load impedance change rate exceeds the first threshold, while the amplitude deviation rate is lower than the second threshold, and the power adjustment rate exceeds the third threshold, the current load impedance change is determined to be caused by operator manipulation. This combination typically corresponds to a sudden application of pressure by the operator, leading to a rapid increase in load, followed by a significant power adjustment to maintain stable blade amplitude. 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 may exhibit different patterns, such as a load impedance change rate lower than the first threshold (i.e., relatively slow change), or a large amplitude deviation after power adjustment. These situations differ from the typical response pattern caused by operator manipulation. Therefore, by setting clear judgment rules, two main sources of load impedance change can be distinguished, providing a basis for subsequent power adjustments based on different sources and improving the effectiveness of power control.

[0135] The specific value of the preset first threshold can be determined experimentally: under typical operating techniques (such as rapid movement and angle adjustment), record the rate of change of load impedance, and take the data value in which 95% of the collected data values ​​are lower than this threshold as the preset first threshold; at the same time, verify that the preset threshold is significantly higher than the rate of change of impedance caused by differences in tissue characteristics (such as the maximum rate of change when cutting dense tissue).

[0136] The second threshold needs to be determined through cutting experiments: under the premise of maintaining cutting efficiency and the decrease in cutting efficiency not exceeding 10%, the amplitude deviation rate under different operating techniques (such as moving speed) and tissue types (such as liver, fascia) is measured, and the maximum allowable value is taken as the threshold (such as 5%).

[0137] The preset third threshold is the power adjustment rate (unit: W / s), which needs to be calibrated according to the performance of the ultrasonic scalpel's power module: measure the time required for the power supply to rise from the minimum power to the maximum power, calculate the maximum allowable rate (e.g., 200W / s), and reserve a 20% safety margin (e.g., set the threshold to 160W / s).

[0138] In practical applications, for example, a first threshold might be set to 5% / ms, a second threshold to 3%, and a third threshold to 2W / ms. For instance, if at a certain moment, the load impedance is detected to change from 100Ω to 130Ω within 5ms, the calculated load impedance change rate is 6% / ms. Simultaneously, the target value of the tool head amplitude is 50μm, and the actual amplitude remains between 49.5μm and 50.5μm within the same time period (5ms), the calculated amplitude deviation rate is 1%. Furthermore, the power output is adjusted from 30W to 45W within the same time period (5ms), the calculated power adjustment rate is 3W / ms. Since 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 simultaneously. Therefore, it is determined that the load impedance change originates from operator manual adjustment. In another case, if the load impedance changes from 100Ω to 110Ω within 5ms, the calculated load impedance change rate is 2% / ms. Even if the amplitude deviation rate and 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), the source of the load impedance change is determined to be the difference in local tissue characteristics.

[0139] In some implementations, when adjusting the input power of the cutting head based on the source of load impedance change, the adjustment module 23 specifically performs the following:

[0140] The first power adjustment amount is calculated based on the amplitude signal and the preset amplitude target value;

[0141] If the change in load impedance is determined to be caused by differences in local tissue characteristics, then the input power of the cutting head is adjusted according to the first power adjustment amount.

[0142] If the change in load impedance is determined to be caused by the operator's manual adjustment, then the power compensation adjustment amount is obtained from the preset power compensation table based on the amplitude signal. The power compensation adjustment amount is then added to the first power adjustment amount to adjust the input power of the cutter head.

[0143] The core of this scheme lies in adjusting the input power of the cutting head based on the source of the load impedance change. First, the real-time amplitude signal of the cutting head is continuously monitored and compared with a preset amplitude target value to calculate a basic power adjustment amount, i.e., the first power adjustment amount, reflecting the amplitude deviation. This first power adjustment amount aims to correct amplitude deviations from the target value by changing the input power. When the system determines that the load impedance change is caused by the cutting head contacting different tissue characteristics, it directly uses the calculated first power adjustment amount to adjust the input power of the cutting head to maintain amplitude stability. When the system determines that the load impedance change is caused by operator-applied pressure, angle, or speed adjustments, in addition to using the first power adjustment amount, it also consults a pre-built power compensation table based on the current amplitude signal to obtain an additional power compensation adjustment amount. This compensation amount reflects the additional power required under the load conditions caused by the specific operating technique. Finally, the first power adjustment amount and the power compensation adjustment amount are superimposed to form the total power adjustment amount, which is used to adjust the input power of the cutting head. In this way, the system can more accurately respond to load impedance changes from different sources, improving the adaptability of power control.

[0144] Specifically, this technical solution addresses the problem that a single power adjustment strategy cannot effectively handle load impedance changes from different sources. First, it acquires the real-time amplitude signal of the cutting head and a preset target amplitude value, calculates the deviation between them, and calculates a first power adjustment amount based on this deviation. This first power adjustment amount is the foundation for maintaining amplitude stability. Then, different power adjustment logics are executed based on the source of the load impedance change determined in the previous steps. If the load impedance change is determined to originate from differences in local tissue characteristics, indicating that the load impedance change is caused by the tissue's inherent properties, the calculated first power adjustment amount is directly used to adjust the cutting head's input power, thereby reducing the impact of tissue characteristic changes on the cutting head's amplitude. If the load impedance change is determined to originate from operator manipulation, indicating that the load impedance change is caused by the operator's active behavior, in addition to using the first power adjustment amount, it is also necessary to look up the corresponding power compensation adjustment amount 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 found power compensation adjustment amount is added to the first power adjustment amount to obtain the final power adjustment amount, which is then used to adjust the cutting head's input power. This superimposed adjustment method allows the system to provide more targeted compensation when dealing with dynamic load impedance changes caused by operator manipulation, thereby more effectively maintaining amplitude stability or achieving the desired surgical outcome. Thus, by differentiating the sources of load impedance changes and employing corresponding adjustment methods, the accuracy and effectiveness of power regulation are improved.

[0145] In practical applications, assume a preset amplitude target value of 50μm. The system acquires the tool head amplitude signal in real time, for example, the current amplitude is 45μm. The calculated amplitude deviation is -5μm. Based on this deviation, a first power adjustment is calculated using a proportional-integral-differential algorithm, for example, +10W. Simultaneously, the system determines that the load impedance change is caused by operator manipulation. At this point, the system consults a preset power compensation table based on the current amplitude signal (45W) or the load impedance change related to operator manipulation. This power compensation table may store additional compensation required when the amplitude is low and the load increases due to operator manipulation. For example, the table shows a power compensation adjustment of +5W. Finally, the first power adjustment (+10W) is added to the power compensation adjustment (+5W), resulting in a total power adjustment of +15W. The input power to the tool head is increased by 15W. If the change in load impedance is determined to be caused by differences in local tissue characteristics, the input power of the cutting head is adjusted only by the first power adjustment amount (+10W), increasing the input power by 10W. In this way, the system provides additional power compensation for load impedance changes caused by operator technique, thus more effectively maintaining amplitude stability.

[0146] In some implementations, the step of calculating the first power adjustment amount based on the amplitude signal and a 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 that the cutter head is expected to maintain).

[0148] Based on the amplitude deviation value, the first power adjustment amount is calculated using the proportional-integral-differential algorithm.

[0149] The method for calculating the first power adjustment amount based on the amplitude signal and the preset amplitude target value first acquires the current amplitude signal of the cutter head. The real-time acquired amplitude signal 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 to a proportional-integral-derivative (PID) algorithm (e.g., using a PID controller). The PID controller calculates an output value, the first power adjustment amount, based on the amplitude deviation value and its change over time. This first power adjustment amount is used to subsequently adjust the input power of the cutter head. The PID algorithm combines proportional, integral, and derivative control methods: proportional adjustment based on the current deviation, integral adjustment to eliminate steady-state error, and derivative adjustment to predict the trend of deviation changes. Through this combination, the first power adjustment amount used for power adjustment is calculated.

[0150] Specifically, to address the issues of insufficient control accuracy, slow response, or system oscillation that may result from simply calculating the power adjustment, this solution employs a proportional-integral-derivative (PID) algorithm to calculate the first power adjustment. First, the amplitude signal of the cutting head is acquired in real time and compared with a 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. Then, this amplitude deviation value is input to the PID controller. The PID controller calculates the proportional, integral, and derivative terms based on preset proportional coefficients (Kp), integral coefficients (Ki), and derivative coefficients (Kd). The proportional term is proportional to the current amplitude deviation; the integral term is proportional to the cumulative amplitude deviation over time (integral); and the derivative term is proportional to the rate of change of the amplitude deviation over time (derivative). These three calculated terms are then added together to obtain the final first power adjustment. For example, the first power adjustment = Kp * (current deviation) + Ki * (integral of deviation) + Kd * (derivative of deviation). This calculated initial power adjustment is then used to adjust the input power of the tool head to reduce amplitude deviation and maintain the tool head amplitude at a preset target value. Using a PID algorithm for calculation comprehensively considers current deviation, historical deviation, and deviation trends, thus calculating a more reasonable and stable initial power adjustment, which helps maintain the stability of the tool head amplitude.

[0151] In some specific implementations, calculating the first power adjustment based on the amplitude signal and the preset amplitude target value can be achieved as follows: The system acquires the amplitude signal of the cutting head in real time, for example, once every 1 millisecond. The preset amplitude target value is set to 55 micrometers. At a certain moment, the acquired amplitude signal is 53 micrometers. The amplitude deviation value is calculated as: 53 micrometers - 55 micrometers = -2 micrometers. This deviation value is input into the PID controller. The parameters of the PID controller are preset as follows: proportional coefficient Kp = 10, integral coefficient Ki = 5, and derivative coefficient Kd = 2. The controller calculates the proportional term: 10 * (-2) = -20. At the same time, the controller accumulates historical deviations to calculate the integral term and calculates the rate of change of the current deviation to calculate the derivative term. Assuming that after calculation, the integral term is -5 and the derivative term is -4, the calculated first power adjustment is: -20 + (-5) + (-4) = -29. This -29 is the suggested power adjustment, indicating that the power needs to be reduced. This calculation process continues, dynamically calculating the power adjustment amount based on the real-time amplitude deviation and applying it to the power output control circuit of the ultrasonic scalpel, thereby driving the scalpel head amplitude to approach and maintain stability towards the target value of 55 micrometers.

[0152] In some implementations, when the adjustment module 23 retrieves the power compensation adjustment amount from a preset power compensation table based on the amplitude signal, it specifically performs the following:

[0153] Read the power compensation table; the power compensation table is obtained by pre-constructing a mapping relationship between the load impedance change caused by operator adjustment and the power compensation adjustment amount;

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

[0155] The average value of the load impedance change is calculated based on multiple load impedance signals, and this value is used as the load impedance change caused by the operator's manual adjustment.

[0156] Based on the change in load impedance caused by the operator's adjustment and the power compensation table, obtain the corresponding power compensation adjustment amount.

[0157] The power compensation table provides the foundational data for compensation lookup. This table is derived by pre-establishing a mapping between load impedance changes caused by operator adjustments and the corresponding power compensation adjustments. Multiple load impedance signals within a preset time window are acquired, providing data samples for calculating load impedance changes. The average load impedance change is calculated from these signals, yielding a representative value for the load impedance change caused by operator adjustments. This averaging process smooths signal fluctuations and more stably reflects the average load impedance change caused by operator adjustments over a period, improving the stability of the input used to find the compensation amount. Based on the load impedance change caused by operator adjustments and the power compensation table, the corresponding power compensation adjustment is obtained. Using the calculated load impedance change for lookup, the required power compensation value for the operator's adjustments can be directly obtained, improving the targeting of power compensation.

[0158] Specifically, this scheme provides a method for obtaining the power compensation adjustment amount, used to adjust the input power of the tool head when the source of the load impedance change is determined to be due to operator manipulation. First, a pre-built power compensation table is read, which establishes the correspondence between the load impedance change caused by operator manipulation and the required power compensation adjustment amount. 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 100Hz within a 1-second time window. Then, based on the acquired load impedance signals, the average value of the load impedance change is calculated; for example, the average value of the change in load impedance at each sampling point relative to the load impedance at the beginning of the window is calculated, or the average value of the change in load impedance at adjacent sampling points is calculated. This average value is determined as the load impedance change caused by operator manipulation. Finally, the calculated representative load impedance change caused by operator manipulation is used as input to look up the corresponding power compensation adjustment amount in the power compensation table. Since the power compensation table is constructed based on the load impedance change from this specific source, the calculated load impedance change can be used to directly obtain the power compensation value required for operator adjustments. This scheme directly links the specific cause of the load impedance change with the required compensation amount by calculating the load impedance change caused by operator adjustments and using this as a basis to look up the compensation value in the table, thus improving the accuracy of power compensation.

[0159] In some specific implementations, the power compensation table can be pre-calibrated experimentally. For example, in a simulated surgical scenario, by simulating different operator techniques (such as changes in pressure and movement speed), the resulting changes in load impedance are recorded, along with the additional power adjustment required to maintain amplitude stability. These data are processed to establish a mapping between the changes in load impedance and the required power compensation adjustment, forming the power compensation table. In practical applications, a preset time window is set, such as 0.5 seconds. The system continuously acquires load impedance signals within this window. Assuming that a series of load impedance values ​​are acquired within a 0.5-second window, the average change of these values ​​relative to the initial value of the window is calculated to be +50Ω. The system reads the preset power compensation table, which may contain entries such as: 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, 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, together determining the final input power adjustment value. Therefore, the system can provide more accurate power compensation for load impedance changes caused by operator technique, helping to maintain stable tool head amplitude.

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

[0161] Obtain the preset proportional coefficient, integral coefficient, and differential coefficient, which are pre-calibrated according to the size of the cutting head and the type of tissue being cut;

[0162] Calculate the proportional term based on the amplitude deviation value and the proportionality coefficient; calculate the integral term based on the integral of the amplitude deviation value and the integral coefficient; calculate the differential term based on the differential of the amplitude deviation value and the differential coefficient.

[0163] Adding the proportional, integral, and derivative terms together yields the first power adjustment.

[0164] This technical solution details how to calculate the first power adjustment using a proportional-integral-derivative (PID) algorithm. First, preset proportional, integral, and derivative coefficients are obtained. These coefficients are the core parameters of the PID controller. By pre-calibrating these coefficients according to the size of the blade and the type of tissue being cut, the PID controller can be optimized for different ultrasonic scalpel systems. This solves the problem of poor control performance caused by coefficient mismatch when simply applying the PID algorithm, ensuring the adaptability and effectiveness of the controller in different surgical environments. Next, 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 derivative term is calculated by multiplying the rate of change of the amplitude deviation value by the derivative coefficient. Finally, the calculated proportional, integral, and derivative terms are superimposed to obtain the final first power adjustment.

[0165] Specifically, since the control effect of the proportional-integral-derivative (PID) algorithm depends on the selection of proportional, integral, and derivative coefficients, 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, failing to effectively maintain the stability of the cutter head amplitude and affecting cutting performance and safety. By pre-calibrating the proportional, integral, and derivative coefficients according to the cutter head size and the type of tissue being cut, the PID algorithm can be optimized for different cutter heads and tissues. Therefore, based on the amplitude deviation value, the proportional, integral, and derivative terms are calculated using these preset coefficients, and they are added together to obtain the first power adjustment amount. This ensures that the first power adjustment amount calculated based on the amplitude deviation can accurately adjust the input power of the cutter head, thereby effectively maintaining the cutter head amplitude near the target value and guaranteeing the cutting performance and safety of the ultrasonic scalpel in different surgical scenarios.

[0166] In some specific implementations, for example, when cutting liver tissue using a blade of a specific size (e.g., 5 mm in diameter), a set of proportional, integral, and differential coefficients (e.g., Kp = 10, Ki = 2, Kd = 0.5) are pre-calibrated for the blade size and tissue type. During the surgery, the amplitude signal of the blade is acquired in real time, and its deviation from the preset amplitude target value (e.g., 50 micrometers) is calculated. If the current amplitude deviation is +5 micrometers, the proportional term is calculated as 10 * 5 = 50. Simultaneously, based on the integral of the historical amplitude deviation value and the rate of change of the current amplitude deviation value, integral and differential terms are calculated respectively; 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 implementations, when the adjustment module 23 analyzes the power adjustment parameters to maintain the stability of the cutter head's amplitude within a preset time, obtains the power adjustment amplitude, and calculates the power adjustment rate, it specifically performs the following:

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

[0169] The corresponding power output value is found based on the control signal of the power adjustment parameter, and the difference between the power output values ​​at adjacent time points is calculated to obtain the power adjustment amplitude.

[0170] The power adjustment rate is obtained by calculating the ratio of the change in power adjustment amplitude within a preset time window to a preset time interval.

[0171] In some implementations, the method further includes the following steps prior to calculating the power adjustment rate:

[0172] The power adjustment amplitude is filtered.

[0173] 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 this table, the internal control signal can be converted into the actual power output value. Further, based on the control signal of the power adjustment parameter, the corresponding power output value is looked up 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. This amplitude quantifies the amount of power adjustment made to maintain the stability of the cutter head amplitude within a short period. Therefore, the ratio of the change in power adjustment amplitude within a preset time window to a preset time interval is calculated to obtain the power adjustment rate, which reflects the speed of power adjustment change over time.

[0174] Specifically, to determine the source of load impedance changes, it is necessary to quantify the power adjustment behavior used to maintain stable blade amplitude. 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 might be a digital quantity, while the power output is a wattage value. Then, the control signal corresponding to the power adjustment parameters is acquired in real time. Using this control signal, the corresponding actual power output value is found in the power lookup table. At consecutive sampling time points, a series of power output values ​​are acquired, and the instantaneous power adjustment amplitude is obtained 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 within a preset time window (e.g., N consecutive sampling points), and this change is 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 for subsequent determination of the specific source of load impedance changes, such as whether it is due to operator technique adjustments or differences in local tissue characteristics. By providing this quantified power adjustment information, the causes of load impedance changes can be identified more accurately, enabling more targeted power regulation.

[0175] In some implementations, the power lookup table can be stored as a two-dimensional array, with the first column representing the control signal value (e.g., an integer from 0 to 255) and the second column representing the corresponding power output value (e.g., 0 to 100W). The control signal is acquired at a sampling rate of 100Hz. In 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 shows a corresponding power of 60W. In the next sampling period, if the control signal changes to 155, the corresponding power is 62W, then the power adjustment amplitude within that sampling interval is 62W - 60W = 2W. 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 sum of the absolute values ​​of the power adjustment amplitude calculated for each sampling period is accumulated, for example, a sum of 15W. The power adjustment rate can then be calculated as 15W / 0.1 seconds = 150W / s. This calculated power adjustment amplitude and rate are then used to determine the source of the load impedance change.

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

[0177] The power adjustment amplitude is filtered.

[0178] Filtering the power adjustment amplitude can reduce noise components and data fluctuations, thereby improving the reliability of subsequent power adjustment rate calculations. This filtering process can be implemented using various signal processing methods, such as digital filters.

[0179] Specifically, after acquiring the power adjustment amplitude, it is input into a filter module. This filter module processes the input power adjustment amplitude data according to a preset filtering algorithm. The processed power adjustment amplitude data has reduced noise components and decreased fluctuations. Subsequently, the power adjustment rate is calculated using the filtered power adjustment amplitude data. The calculated power adjustment rate data has higher reliability, which helps improve the accuracy of determining the source of load impedance changes. Accurate determination of the source of load impedance changes enables the power control system to more precisely adjust the power according to the source of load impedance changes, optimizing the performance of the ultrasonic scalpel.

[0180] In some specific implementations, a moving average filter can be used to filter the power adjustment amplitude. For example, a time window of length N can be set. At each time point, the power adjustment amplitude data of the current time point and the previous N-1 time points are acquired. The average of these N power adjustment amplitude data points is calculated, and this average is used as the filtered power adjustment amplitude of the current time point. This smooths 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 results and improve the accuracy of the judgment.

[0181] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0182] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An ultrasonic scalpel power control system, characterized in that, include: The acquisition module is used to acquire the amplitude signal and load impedance signal of the cutting head in real time; The judgment module is used to determine the source of the load impedance change based on the amplitude signal and the load impedance signal; When the judgment module determines the source of load impedance change based on the amplitude signal and the load impedance signal, it specifically performs the following: The amplitude signal is compared with the preset amplitude target value to obtain the amplitude deviation value, and the amplitude deviation rate is calculated. Analyze the power adjustment parameters that maintain the stable amplitude of the cutter head within a preset time to obtain the power adjustment amplitude and calculate the power adjustment rate; Monitor the load impedance signal, obtain the load impedance change, and calculate the load impedance change rate; The source of the load impedance change is determined based on the amplitude deviation rate, the load impedance change rate, and the power adjustment rate. When the judgment module determines the source of load impedance change based on the amplitude deviation rate, the load impedance change rate, and the power adjustment rate, it specifically performs the following: 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, then the source of the load impedance change is determined to be operator manual adjustment; otherwise, the source of the load impedance change is determined to be tissue local characteristic difference. An adjustment module is used to adjust the input power of the cutter head according to the source of the load impedance change.

2. The ultrasonic scalpel power control system according to claim 1, characterized in that, When the adjustment module adjusts the input power of the cutting head based on the source of the load impedance change, it specifically performs the following: The first power adjustment amount is calculated based on the amplitude signal and the preset amplitude target value; If it is determined that the change in load impedance is caused by differences in local tissue characteristics, then the input power of the blade is adjusted according to the first power adjustment amount; If it is determined that the change in load impedance is caused by the operator's manual adjustment, then based on the amplitude signal, the power compensation adjustment amount is obtained from the preset power compensation table, and the power compensation adjustment amount is added to the first power adjustment amount to adjust the input power of the cutter head.

3. The ultrasonic scalpel power control system according to claim 2, characterized in that, When the adjustment module calculates the first power adjustment amount based on the amplitude signal and the preset amplitude target value, it specifically performs the following: The amplitude deviation value is calculated based on the amplitude signal and the preset amplitude target value; Based on the amplitude deviation value, the first power adjustment amount is calculated using a proportional-integral-differential algorithm.

4. The ultrasonic scalpel power control system according to claim 2, characterized in that, When the adjustment module retrieves the power compensation adjustment amount from the preset power compensation table based on the amplitude signal, it specifically performs the following: Read the power compensation table; the power compensation table is obtained by pre-constructing a mapping relationship between the load impedance change caused by operator adjustment and the power compensation adjustment amount; Acquire multiple load impedance signals within a preset time window; The average value of the load impedance change is calculated based on multiple load impedance signals, and used as the load impedance change caused by operator adjustment. Based on the change in load impedance caused by the operator's adjustment and the power compensation table, obtain the corresponding power compensation adjustment amount.

5. The ultrasonic scalpel power control system according to claim 3, characterized in that, When the adjustment module calculates the first power adjustment amount based on the amplitude deviation value using a proportional-integral-differential algorithm, it specifically performs the following: Obtain preset proportional coefficients, integral coefficients, and differential coefficients, which are pre-calibrated according to the size of the cutting head and the type of tissue being cut; The proportional term is calculated based on the amplitude deviation value and the proportionality 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 derivative of the amplitude deviation value and the differential coefficient. The first power adjustment amount is obtained by adding the proportional term, the integral term, and the differential term.

6. The ultrasonic scalpel power control system according to claim 1, characterized in that, When the judgment module analyzes the power adjustment parameters that maintain the stability of the cutter head's amplitude within a preset time, obtains the power adjustment amplitude, and calculates the power adjustment rate, it specifically performs the following: Read the power lookup table, which is a mapping table between the control signals corresponding to the power adjustment parameters and the power output; The corresponding power output value is found based on the control signal of the power adjustment parameter, and the difference between the power output values ​​at adjacent time points is calculated to obtain the power adjustment amplitude. The power adjustment rate is obtained by calculating the ratio of the change in power adjustment amplitude within a preset time window to a preset time interval.

7. The ultrasonic scalpel power control system according to claim 6, characterized in that, Before calculating the power adjustment rate, the determination module also performs the following: The power adjustment amplitude is filtered.

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