A medical ultrasonic scalpel power testing device

Abstract

The application belongs to the technical field of ultrasonic knife testing, and particularly relates to a medical ultrasonic knife power testing device, which comprises a cabin body divided into an upper sealed testing cabin and a lower dry driving cabin by a partition; a temperature and humidity adjusting assembly arranged in the sealed testing cabin, a dynamic dripping assembly arranged opposite to a testing load, and a negative pressure waste discharge assembly connected with an external liquid pumping machine; the sealed testing cabin is further provided with an anti-fog observation window; a servo driving assembly arranged in the dry driving cabin comprises a servo motor and a linear transmission mechanism, an output end of the servo driving assembly penetrates through a rotary sealing piece of the partition, extends into the sealed testing cabin and is connected with a load clamp; a sensing array comprises a temperature and humidity sensor in the sealed testing cabin, a dynamic pressure sensor in the negative pressure waste discharge assembly, an encoder of the servo motor, a force sensor at the bottom of the load clamp and an impedance spectrum sensor below the testing load; the continuous effectiveness and safety of the testing under the high-humidity condition of the simulated human body are ensured.

Description

Technical Field

[0001] This invention belongs to the field of ultrasonic scalpel testing technology, specifically a medical ultrasonic scalpel power testing device. Background Technology

[0002] As a core surgical instrument for cutting and coagulating biological tissues in minimally invasive surgery, the accuracy and stability of the output acoustic power of the medical ultrasonic scalpel directly affect surgical safety. In order to ensure the accuracy calibration of the ultrasonic scalpel before leaving the factory and the reliability verification during long-term use, the medical ultrasonic scalpel power testing device has become an indispensable basic support equipment in the engineering inspection and quality control system of medical devices.

[0003] Currently, the mainstream ultrasonic scalpel testing platforms in the industry mainly rely on a uniaxial static pressure architecture under normal temperature and dry conditions. These devices can usually only perform basic electrical power calculations and mechanical amplitude verifications by pressing the ultrasonic scalpel head against a standard test block with a fixed stroke and pressure in an ideal laboratory air medium. However, as clinical minimally invasive surgery becomes more complex, this measurement method, which highly idealizes the test boundary, is severely disconnected from the real clinical surgical pain points, resulting in serious distortion of the factory calibration data in actual surgical applications.

[0004] Upon closer examination, the real-world abdominal surgery scenario presents a complex physical condition characterized by high humidity (around 37 degrees Celsius) and continuous immersion in fluids such as blood and saline. When existing dry calibration equipment attempts to introduce external liquids to simulate wet conditions, numerous structural and control defects are exposed: On the one hand, the single-layer test environment without temperature difference suppression design causes the dripped liquid to evaporate and condense rapidly, making the optical observation window and vibration measurement lens prone to fogging, directly blocking the optical path of non-contact optical vibration measurement; on the other hand, the open mechanical transmission platform cannot resist the penetration and erosion of liquids, and waste liquid can easily seep into the servo motor and sensing circuit at the bottom along the pressure shaft, causing corrosion and jamming of transmission components and electrical short circuits. More critically, existing equipment lacks a dynamic compensation mechanism for the high-frequency acoustic impedance mutations caused by wet immersion and the thermal expansion displacement of the blade body, causing the preset static pressure stroke to easily generate overload pressure that damages the phantom modulus under thermal deformation, resulting in a serious disconnect between the measured electrical power and the actual output acoustic power of the blade tip.

[0005] Therefore, the present invention provides a medical ultrasonic scalpel power testing device. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is: a medical ultrasonic scalpel power testing device according to this invention, comprising: The cabin is divided into an upper sealed test chamber and a lower dry drive chamber by a partition; The sealed test chamber contains a temperature and humidity control component, a dynamic dripping component positioned opposite the test load, and a negative pressure waste discharge component connected to an external pump; the sealed test chamber is also equipped with an anti-fog observation window. The servo drive assembly located in the drying drive chamber includes a servo motor and a linear transmission mechanism. Its output end extends through the rotary seal of the partition into the sealing test chamber and is connected to the load clamp. The sensor array includes a temperature and humidity sensor in the sealed test chamber, a dynamic pressure sensor in the negative pressure waste discharge assembly, an encoder for the servo motor, a force sensor at the bottom of the load fixture, and an impedance spectrum sensor below the test load. The main control unit is communicatively connected to the temperature and humidity control component, the dynamic dripping component, the servo drive component, and the sensor array. The main control unit is configured to: construct a thermal boundary effectiveness model and a liquid path anti-seepage isolation model based on the data from the sensor array, and construct an acoustic-mechanical coupling maintenance model by combining the dynamic mechanical modulus and the reference acoustic power; further, integrate the thermal boundary effectiveness, acoustic-mechanical coupling maintenance, and electrical resonance parameters to generate multimodal test fidelity; finally, output servo compensation time difference based on the multimodal test fidelity and the liquid path anti-seepage isolation, and perform dynamic force-position hybrid compensation control on the thermal expansion displacement of the ultrasonic scalpel rod through the servo drive component.

[0008] The beneficial effects of this invention are as follows: 1. This invention, by setting up an upper sealed test chamber and a lower drying drive chamber separated by a partition, and in conjunction with a rotating seal, a negative pressure waste discharge component, and an anti-fog observation window, achieves physical isolation between the test environment and the drive mechanism and unidirectional liquid discharge. This effectively avoids waste liquid seeping into the motor and sensor circuit during wet testing, causing corrosion and short circuits. At the same time, it suppresses the obstruction of the optical vibration measurement path by the fog in the chamber, ensuring the continuous effectiveness and safety of testing under simulated high humidity conditions of the human body.

[0009] 2. This invention establishes an acoustic-mechanical coupling maintenance model constructed by the main control unit. Based on the real-time change rate of elastic modulus and the attenuation rate of acoustic power in dry and wet states, it performs continuous variance distribution mapping on the mechanical distortion and acoustic impedance characteristics under the liquid immersion boundary, realizing real-time quantitative evaluation of the energy coupling stability of the ultrasonic scalpel. This overcomes the problem of high-frequency impedance mutation caused by wet immersion leading to the disconnect between electrical power and scalpel tip acoustic power, and significantly improves the authenticity and validity of the test data.

[0010] 3. This invention establishes a multimodal test fidelity model generated by a multidimensional feature fusion inverse suppression function. It nonlinearly fuses the thermal boundary effectiveness, acoustic-mechanical coupling maintenance, and electrical resonance parameters, and introduces electrical phase misalignment and liquid film impedance distortion as penalty excitations. This enables dynamic evaluation of the global fidelity of the test state. Furthermore, by combining the liquid circuit anti-permeability isolation output servo compensation time difference, it provides a precise force-position hybrid compensation basis for the thermal expansion displacement of the ultrasonic scalpel. Attached Figure Description

[0011] The invention will now be further described with reference to the accompanying drawings.

[0012] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the sealed test chamber in this invention; Figure 3 This is a flowchart of the overall scheme for testing the power of the medical ultrasonic scalpel in this invention; Figure 4 This is a flowchart of the construction of the thermal boundary effectiveness model and the dynamic evaluation of the phase transition critical point of the present invention; Figure 5 This is a flowchart of the parallel solution of the dual-track characteristics of the machine and the evaluation of the coupling degree between the machine and the acoustic mechanism in this invention; Figure 6 This is a flowchart of the multimodal test fidelity fusion and dynamic force-position compensation control of the present invention.

[0013] In the diagram: 1. Drying drive chamber; 2. Sealing test chamber; 3. Anti-fog observation window; 4. Liquid pump; 5. Linear transmission mechanism; 6. Load clamp; 7. Dynamic drip assembly; 8. Partition. Detailed Implementation

[0014] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0015] like Figures 1 to 2 As shown, the medical ultrasonic scalpel power testing device of the present invention includes: a chamber, which is divided into an upper sealed test chamber 2 and a lower dry drive chamber 1 by a partition 8, so as to achieve physical isolation between the test environment and the drive mechanism. The main structure of the chamber is made of high-strength, corrosion-resistant engineering plastic or metal material, and the partition 8 can be made of a material with good sealing performance, such as silicone or fluororubber gaskets, and fixed with mechanical fasteners.

[0016] Inside the sealed test chamber 2, there are temperature and humidity control components, dynamic dripping components 7, and negative pressure waste discharge components. The sealed test chamber 2 also has an anti-fog observation window 3. The temperature and humidity control components include a heater, a humidifier, and temperature and humidity sensors. The temperature and humidity inside the chamber are regulated through a simple PID control algorithm. The dynamic dripping components 7 can be composed of a liquid storage tank, a peristaltic pump, and a dripping nozzle. The dripping frequency and liquid volume can be manually set. The negative pressure waste discharge components can be a simple drain outlet connected to an external liquid pump 4. Waste liquid is discharged by manually starting the liquid pump 4. The anti-fog observation window 3 can be a single-layer glass window. Its anti-fog effect depends on the stability of the temperature and humidity inside the chamber, so as to initially simulate the test conditions in a high humidity environment and provide basic observation and waste liquid treatment functions.

[0017] Inside the drying drive chamber 1, there is a servo drive assembly, which includes a servo motor and a linear transmission mechanism 5. The output end of the servo motor extends through the rotary seal of the partition 8 into the sealed test chamber 2 and is connected to the load clamp 6. The servo drive assembly uses a stepper motor and a ball screw to achieve linear transmission. The displacement of the load clamp 6 is achieved through simple open-loop control. The rotary seal uses a traditional oil seal or O-ring. Its sealing performance may be subject to wear and leakage after high-speed rotation or long-term use. The load clamp 6 can be a simple mechanical clamp that fixes the test load with bolts to achieve basic pressure and displacement control of the test load.

[0018] like Figures 3 to 6 As shown, the sensor array is a key component of the device, comprising a temperature and humidity sensor inside the sealed test chamber 2, a dynamic pressure sensor inside the negative pressure exhaust assembly, an encoder for the servo motor, a force sensor at the bottom of the load clamp 6, and an impedance spectrum sensor below the test load. The temperature and humidity sensor can be a thermistor or a capacitive humidity sensor to provide basic data on the chamber environment. The dynamic pressure sensor is a piezoresistive sensor to monitor pressure changes in the exhaust pipeline. The encoder for the servo motor is an incremental encoder to provide the basic pulse signal for motor rotation. The force sensor is a resistance strain gauge sensor to measure the force at the bottom of the load clamp 6. The impedance spectrum sensor is a simple LCR meter to measure the impedance value of the test load. These sensors collect multi-dimensional data during the test process, providing raw information for subsequent analysis.

[0019] The main control unit is communicatively connected to the temperature and humidity control component, the dynamic dripping component 7, the servo drive component, and the sensor array. The main control unit is configured to: construct a thermal boundary effectiveness model and a liquid path impermeability isolation model based on data from the sensor array; and construct an acoustic-mechanical coupling maintenance model by combining dynamic mechanical modulus and reference acoustic power. Furthermore, it integrates the thermal boundary effectiveness, acoustic-mechanical coupling maintenance, and electrical resonance parameters to generate multimodal test fidelity. Finally, based on the multimodal test fidelity and the liquid path impermeability isolation, it outputs servo compensation time difference, and uses the servo drive component to dynamically control the thermal expansion displacement of the ultrasonic scalpel rod. Hybrid compensation control uses an embedded controller as the main control unit. It processes sensor data through a preset simple linear model and performs basic logical judgments. The thermal boundary effectiveness model is a simple threshold judgment. When the temperature and humidity are within the set range, the effectiveness is considered high. The liquid circuit anti-seepage isolation model is a simple comparison of pressure differences. The acoustic-mechanical coupling maintenance model is a calculation based on an empirical formula. The multimodal test fidelity can be achieved by simply weighting the results of these models. The servo compensation time difference is an output based on a fixed lookup table, which performs simple displacement compensation through a servo drive component.

[0020] In actual testing, the medical ultrasonic scalpel to be tested is first mounted on the load clamp 6, which is located inside the sealed test chamber 2. The servo drive assembly that drives the load clamp 6 is located in the dry drive chamber 1 below. The two are physically isolated by the partition 8 and the rotating seal.

[0021] At the start of the test, the main control unit first activates the temperature and humidity control component to control the temperature inside the sealed test chamber 2 at 37 degrees Celsius and raise the relative humidity to the preset high humidity level. At the same time, the anti-fog observation window 3 ensures that the test personnel can clearly observe the contact between the ultrasonic scalpel and the test load through its anti-fog function, avoiding the problem of fogging of the observation window in the traditional device under humid and hot conditions.

[0022] Subsequently, the dynamic dripping component 7 began to precisely drip physiological saline onto the surface of the test load, simulating the scenario of continuous tissue infiltration during surgery. Throughout the test, the sensor array continuously collected multi-dimensional data: the temperature and humidity sensor monitored the environmental parameters inside the sealed test chamber 2 in real time; the dynamic pressure sensor monitored the pressure inside the negative pressure waste discharge component to ensure that the waste liquid could be effectively discharged by the negative pressure waste discharge component and prevent liquid leakage into the drying drive chamber 1; the encoder of the servo motor provided real-time feedback on the precise position of the load clamp 6; the force sensor at the bottom of the load clamp 6 measured the force applied by the ultrasonic scalpel to the test load in real time; and the impedance spectrum sensor below the test load monitored the acoustic impedance change between the ultrasonic scalpel and the wet test load in real time.

[0023] After receiving real-time data from the sensor array, the main control unit begins complex calculations and model building. Based on the data from the temperature and humidity sensors, the main control unit constructs a thermal boundary effectiveness model to evaluate the stability and compliance of the test environment. Based on the data from the dynamic pressure sensor, it constructs a liquid path anti-seepage isolation model to monitor the sealing performance of the waste discharge system and ensure no liquid leakage. At the same time, the main control unit combines the data from the force sensor and encoder with the preset reference acoustic power to construct an acoustic-mechanical coupling maintenance model to evaluate the acoustic and mechanical coupling state between the ultrasonic scalpel and the test load in a humid environment in real time.

[0024] Furthermore, the main control unit integrates the calculated thermal boundary effectiveness, acoustic-mechanical coupling maintenance, and electrical resonance parameters obtained from the ultrasonic scalpel excitation circuit to generate a comprehensive multimodal test fidelity index. This index reflects the realism of the current test environment, the stability of the acoustic-mechanical coupling, and the matching degree of the electrical resonance.

[0025] Finally, based on the real-time calculated multimodal test fidelity and liquid path impermeability isolation, the main control unit outputs a servo compensation time difference. This servo compensation time difference is sent to the servo drive component to guide the servo motor and linear transmission mechanism 5 to make precise dynamic adjustments to the load clamp 6. When the ultrasonic scalpel rod generates a small thermal expansion displacement due to heat after long-term operation, the main control unit will determine whether the test conditions deviate from the ideal state based on the multimodal test fidelity, and combine the liquid path impermeability isolation to ensure system safety. Then, it calculates the required compensation time difference and drives the servo drive component to perform dynamic force-position hybrid compensation control, adjusting the position of the load clamp 6 in real time to counteract the thermal expansion displacement of the ultrasonic scalpel rod. This ensures that the ultrasonic scalpel tip and the test load always maintain the preset contact force and cutting depth, avoiding overload pressure or poor contact caused by thermal deformation, thereby ensuring the accuracy and consistency of ultrasonic scalpel power testing in a humid environment.

[0026] The thermal boundary effectiveness model is constructed based on a nonlinear asymptotic convergence function. The main control unit calculates the time hysteresis penalty term based on the ratio of the time taken to achieve the humidity standard in the sealed test chamber 2 to the benchmark time. Based on the ratio of the difference between the actual measured temperature and the dew point temperature to the benchmark temperature difference, the unit suppresses the risk of condensation phase change through smooth threshold mapping and outputs a normalized effectiveness coefficient.

[0027] The thermal boundary effectiveness model is as follows: In the formula, For thermal boundary effectiveness; The time when the humidity inside the sealed test chamber 2 reaches the standard; This marks the start time of temperature and humidity regulation. For actual temperature measurement; This refers to the dew point temperature. These are the baseline tolerance time constant and the temperature difference constant, respectively; Environmental hysteresis weight constant.

[0028] Among them, thermal boundary effectiveness Used to quantitatively evaluate the stability and suitability of the test environment, it comprehensively considers the time efficiency required for the ambient humidity to stabilize and the condensation risk reflected by the difference between the actual temperature and the dew point temperature, thus providing a comprehensive indicator to determine whether the current test environment is within the effective boundary required for ultrasonic scalpel power testing.

[0029] Humidity reaches standard in sealed test chamber 2 This refers to the moment when the relative humidity inside the sealed test chamber 2 first reaches the preset target value (e.g., 95%) after the temperature and humidity control component is activated. Accurate recording of this moment is crucial for evaluating the response speed and environmental stability efficiency of the temperature and humidity control component. This can be achieved by continuously monitoring the temperature and humidity sensor data inside the sealed test chamber 2 through the main control unit and recording a timestamp when the humidity value first meets the preset conditions.

[0030] Temperature and humidity regulation start time This refers to the initial time point at which the main control unit issues a command to start the temperature and humidity control component to begin temperature and humidity control of the sealed test chamber 2. This moment is the benchmark point for calculating the time taken for the temperature and humidity control process, which is achieved by the main control unit automatically recording the system time when starting the temperature and humidity control program.

[0031] Actual measured temperature This refers to the current ambient temperature measured in real time by temperature and humidity sensors inside the sealed test chamber 2 during the ultrasonic scalpel power test. It is an input parameter for assessing the thermodynamic state of the environment and calculating the dew point temperature. The main control unit periodically reads data from the temperature and humidity sensors inside the sealed test chamber 2.

[0032] Dew point temperature Dew point temperature refers to the temperature at which water vapor in the air reaches saturation and begins to condense into liquid water (dew) under constant air pressure. In the ultrasonic scalpel power testing device, dew point temperature is an indicator for evaluating the anti-fogging performance and condensation risk within the sealed test chamber 2. When the actual measured temperature is close to or lower than the dew point temperature, condensation may occur on the anti-fogging observation window 3 or the surface of the test load, affecting test accuracy and observation. Dew point temperature can be directly measured using a dew point sensor.

[0033] Baseline tolerance time constant This represents the maximum time that the system can tolerate from the start of the temperature and humidity regulation process until the humidity reaches the standard. It is a preset benchmark value used to measure whether the temperature and humidity regulation efficiency is within an acceptable range. This constant is set by conducting multiple standard environmental regulation experiments on the device, statistically analyzing the time required for it to reach stability, and combining engineering experience.

[0034] Temperature difference constant This represents the minimum safe temperature difference that the system can tolerate between the actual measured temperature and the dew point temperature when assessing the risk of condensation. It is a preset benchmark value used to determine whether the environment faces the risk of condensation. This constant is determined by conducting condensation critical condition experiments on the device, setting the safe temperature difference range, and combining it with the performance parameters of the anti-fog observation window 3.

[0035] Environmental hysteresis weight constant These constants are used to adjust the weights of the time dimension (humidity compliance efficiency) and the spatial dimension (condensation risk) on the overall effectiveness in the thermal boundary effectiveness model, and to reflect the nonlinear hysteresis characteristics of the environmental response. They are adjustment parameters in the model to enable the model to better fit the dynamic changes of the actual environment. These two constants are calibrated by performing regression analysis and optimization on the operating data of the device under different environmental conditions in order to minimize the model prediction error.

[0036] By constructing a thermal boundary effectiveness model, a quantitative assessment of the test environment state was achieved, providing an environmental benchmark for subsequent power test fidelity calculations. This model consists of a product of two parts; the first part utilizes the humidity threshold at which the test environment meets the standard. With the start time of temperature and humidity regulation The difference, combined with the baseline tolerance time constant With environmental hysteresis weight constant The response speed of the temperature and humidity regulation process is modeled with exponential decay to reflect the efficiency of the environment in reaching a steady state.

[0037] Specifically, the shorter the time required for temperature and humidity regulation, the better. The smaller the value, the closer this part is to 1, indicating high environmental regulation efficiency; conversely, the longer the time taken, the smaller the value, indicating low regulation efficiency. The second part involves actual temperature measurements. With dew point temperature The difference is calculated using the logistic function form, combined with the temperature difference constant. With environmental hysteresis weight constant The risk of condensation and thermodynamic stability in the environment are nonlinearly mapped.

[0038] When the actual measured temperature Much higher than the dew point temperature When the risk of condensation is low, the value of this part is close to 1; while when Close to or below At this time, the risk of condensation is high, and this value drops rapidly, reflecting poor environmental thermodynamic stability.

[0039] The main control unit communicates with the temperature and humidity sensors inside the sealed test chamber 2 to obtain the actual measured temperature in real time. And relative humidity, and calculate the dew point temperature accordingly. Meanwhile, the main control unit records the start-up time of the temperature and humidity control component. It continuously monitors humidity changes until the preset humidity target is reached. Subsequently, the main control unit will process these real-time data and preset reference constants. Substituting the values ​​into the thermal boundary effectiveness model, we obtain the thermal boundary effectiveness of the current environment. .

[0040] By integrating the adjustment efficiency in the time dimension with the thermodynamic stability in the spatial dimension, this model can characterize whether the test environment is within the effective boundary of suitable ultrasonic scalpel power testing. This allows the main control unit to more accurately understand and compensate for measurement deviations caused by environmental fluctuations. The effectiveness of this thermal boundary... As a key input parameter of the multimodal test fidelity model, it is integrated with the acoustic-mechanical coupling degree and electrical resonance parameters to generate the multimodal test fidelity. Finally, based on this fidelity and the liquid circuit anti-permeability isolation degree, the main control unit outputs servo compensation time difference. Through the servo drive component, the thermal expansion displacement of the ultrasonic scalpel rod is dynamically force-position hybrid compensation control is performed, which ensures the accuracy and reliability of ultrasonic scalpel power testing under simulated real surgical environment (such as high humidity and liquid immersion). It effectively solves the problem of data distortion in wet conditions by traditional dry testing methods.

[0041] The dew point temperature is obtained in real time through the nonlinear mapping relationship of thermodynamic state; the main control unit extracts the comprehensive characteristics of the actual measured temperature and real-time relative humidity, and performs continuous algebraic conversion by combining the preset vaporization constant and absolute zero conversion constant to avoid segmented condition judgment and dynamically output the dew point temperature that reflects the critical point of phase change in the cabin.

[0042] The main control unit obtains the dew point temperature in real time using the following nonlinear mapping formula. : In the formula, These are Magnus state parameters; The measured relative humidity; It is the absolute zero constant; These are Magnus's dimensionless constant and the temperature constant, respectively.

[0043] The main control unit, as the control core of the entire device, is responsible for receiving data from the sensor array, executing complex calculation models, and outputting control commands. This main control unit can be an embedded processor, such as a microcontroller based on the ARM architecture. Its functions include data acquisition, model calculation, logical judgment, and command output.

[0044] The nonlinear mapping formula, also known as the Magnus formula, is an empirical formula used to describe the relationship between saturated water vapor pressure and temperature. This formula allows the dew point temperature to be calculated from the actual air temperature and relative humidity. The introduction of this formula enables the system to extract deeper environmental thermodynamic information from simple temperature and humidity measurement data, thereby more accurately assessing the stability of the test environment.

[0045] Dew point temperature Dew point temperature refers to the temperature at which water vapor in the air reaches saturation and begins to condense into liquid water (dew) under a fixed air pressure. It is an important indicator for measuring the water vapor content in the air. When the ambient temperature drops to the dew point temperature, condensation will occur. In the medical ultrasonic scalpel power testing device, real-time acquisition of dew point temperature is crucial for assessing the risk of condensation in the sealed test chamber 2, because condensation will seriously affect the clarity of the optical observation window and the surface condition of the test load, thereby interfering with the test results.

[0046] Magnus state parameters It is an intermediate variable in the Magnus formula, which combines relative humidity and actual temperature in logarithmic and fractional forms to simplify the calculation of dew point temperature. The calculation of this parameter is a crucial step in achieving accurate dew point temperature.

[0047] Measured relative humidity This refers to the ratio of water vapor content in the air inside the sealed test chamber 2 to the saturated water vapor content at the same temperature. It is typically obtained in real-time by a temperature and humidity sensor inside the sealed test chamber 2. This sensor can be a capacitive or resistive humidity sensor with an absolute zero constant. It is a fundamental physical constant that represents the lowest limit of thermodynamic temperature, usually taken as -273.15 degrees Celsius or 0 Kelvin. In the Magnus formula, it is used to convert Celsius temperature to Kelvin temperature to ensure the physical consistency of the formula calculation.

[0048] Magnus dimensionless constant With temperature constant These are the empirical coefficients in Magnus's formula, obtained through experimental calibration (it should be noted here that these are constants). These are Kelvin domain correction coefficients that have been recalibrated after absolute temperature system conversion. They are used to adjust the formula to adapt to different temperature ranges and accuracy requirements. These constants are usually pre-stored in the memory of the main control unit and are called during the calculation process.

[0049] The actual measured temperature inside the sealed test chamber 2 is obtained in real time through the main control unit. and the measured relative humidity And using a preset absolute zero constant and Magnus's dimensionless constant With temperature constant First, calculate the Magnus state parameters. Subsequently, based on this Magnus state parameter Furthermore, the current dew point temperature can be derived by using a nonlinear mapping formula. This process enables the thermal boundary effectiveness model to incorporate dew point temperature during calculation. By incorporating these parameters as key considerations, the wet boundary conditions of the test environment can be more accurately assessed. In this way, the system no longer relies solely on single temperature and humidity values, but instead performs dynamic evaluations based on thermodynamic state parameters, ensuring a high degree of consistency and reliability in determining the effectiveness of the test environment under different environmental conditions.

[0050] The liquid circuit anti-seepage isolation model is constructed using a fluid dynamics saturated damping function. The main control unit uses the difference between the peak and valley pressure in the pipeline as the pulsating disturbance and the hydrostatic pressure determined by the waste liquid density and the height of the waste discharge pipeline as the critical threshold for anti-seepage. The model calculates the ratio of this disturbance to the critical threshold and outputs the safety factor characterizing the unidirectional isolation state of the waste discharge pipeline through a boundary-constrained nonlinear damping mapping.

[0051] The specific model for the impermeability and isolation of the liquid path is as follows: In the formula, For the impermeability and isolation of the liquid path; These represent the peak and valley values ​​of the pipeline pressure, respectively. The density of the waste liquid; It is the acceleration due to gravity; The height of the waste discharge pipeline; The nonlinear damping coefficient for pipeline flow resistance is 3002. This liquid path impermeability and isolation model aims to quantitatively evaluate the impermeability and isolation capability of the waste liquid discharge pipeline of the negative pressure waste discharge component under dynamic operating conditions. Its output value It is a dimensionless parameter between 0 and 1, where 1 represents the ideal state of complete isolation and 0 represents complete failure or no isolation capability. This model provides a unified and quantifiable index for real-time monitoring and evaluation of the safety and reliability of the waste discharge system by comprehensively considering the pressure fluctuations inside the pipeline, the physical properties of the waste liquid, and the geometric dimensions and fluid resistance characteristics of the pipeline.

[0052] Pipeline pressure peak and pipeline pressure trough These represent the highest and lowest pressures that the waste discharge pipeline can reach within a certain time window, reflecting the dynamic fluctuation range of the internal pressure of the pipeline during the waste discharge process. The pressure values ​​are obtained by installing high-precision miniature pressure sensors at key locations in the waste discharge pipeline. The main control unit samples and analyzes the real-time pressure signals output by the sensors to extract the peak and valley values ​​within a specified time period.

[0053] Waste liquid density This refers to the mass per unit volume of waste liquid generated during the test. This parameter is a physical quantity used to calculate the gravitational potential energy of the waste liquid and directly affects the contribution of the liquid column in the pipeline to the pressure. It is set according to the density of physiological saline or blood simulation fluid commonly used in medical ultrasonic scalpel testing to determine the density of the waste liquid.

[0054] gravitational acceleration It is a physical constant. In this model, gravitational acceleration is used to convert the mass of the waste liquid into its gravitational force, and then to calculate the hydrostatic pressure generated by the waste liquid column and the height of the waste discharge pipe. This refers to the maximum vertical height that the waste liquid may reach in the waste discharge pipeline. It is usually the vertical distance from the waste liquid collection point to the waste discharge outlet. This parameter, together with the waste liquid density and gravitational acceleration, determines the maximum hydrostatic pressure that the waste liquid column may generate. It is an important geometric parameter for assessing the risk of waste liquid backflow and the pipeline's impermeability. This height can be determined by structural dimensions during the device design stage, for example, by precise measurement through a CAD model.

[0055] Pipeline flow resistance nonlinear damping coefficient It is an empirical parameter used to characterize the nonlinear resistance encountered by waste liquid when flowing in the waste discharge pipeline, including frictional resistance, local resistance, and energy loss caused by pipeline bending, cross-sectional changes, etc. This coefficient can more realistically reflect the flow characteristics of actual fluid in complex pipeline systems and correct for the influence of pressure fluctuations. This coefficient is obtained through experimental calibration. For example, under different flow rates and waste liquid viscosity conditions, multiple waste discharge experiments are carried out on a specific pipeline system, and regression analysis is performed in combination with the actual measured pressure loss data to determine its value.

[0056] By constructing a liquid circuit anti-permeability isolation model, the sealing and isolation performance of the waste discharge system of the negative pressure waste discharge component was digitally characterized. The core of this model is to quantify the anti-permeability of the waste discharge pipeline under dynamic working conditions, so as to solve the problems of unstable internal pressure fluctuations in the waste liquid discharge pipeline, which can easily lead to waste liquid backflow or incomplete waste discharge, thereby affecting the sealing and safety of the test environment, as well as the lack of quantitative evaluation of the anti-permeability isolation capability of the waste discharge system.

[0057] Specifically, the model utilizes the peak pressure in the waste discharge pipeline. With pipeline pressure trough The difference is used to reflect the pressure fluctuations during the waste discharge process. The larger the difference, the more severe the pressure fluctuations inside the pipeline, and the higher the risk of waste liquid backflow or seepage. The model also incorporates waste liquid density. Gravitational acceleration and the height of the waste discharge pipeline These physical parameters together construct the maximum hydrostatic pressure that the waste liquid column may generate, thereby establishing the ratio between pressure fluctuation and gravitational potential energy, and quantifying the seepage resistance of the waste discharge pipeline in the vertical direction.

[0058] To transform this physical quantification result into an isolation index with mathematical properties, the model utilizes the hyperbolic tangent function for nonlinear mapping. The hyperbolic tangent function has the ability to map any real number to... The properties of the interval can be understood through appropriate transformations (such as subtracting 1 from the interval). (Function) can be used to measure isolation index The smooth mapping to 0 to 1 effectively suppresses computational noise caused by sudden pressure changes, enabling the isolation index to change stably and meaningfully under various operating conditions.

[0059] In addition, the model also incorporates the nonlinear damping coefficient of the pipe flow resistance. This coefficient is used to correct for the friction and local resistance effects experienced by the actual fluid flowing in the pipeline, enabling the model to reflect the true isolation state of the waste discharge system and avoiding errors caused by idealized assumptions. Through the above mechanism, the liquid circuit anti-seepage isolation degree model can evaluate the anti-seepage isolation performance of the waste discharge system in real time and accurately. This quantitative indicator not only provides a scientific basis for assessing the potential permeation risk of waste liquid to the drying drive chamber 1 and the sensing circuit, but also, as a key parameter in the overall test fidelity evaluation system, it is integrated with the thermal boundary effectiveness model, acoustic-mechanical coupling maintenance model and electrical resonance parameters constructed by the main control unit to generate multimodal test fidelity. Finally, based on this and the liquid circuit anti-seepage isolation degree output servo compensation time difference, the servo drive component performs dynamic force-position hybrid compensation control on the thermal expansion displacement of the ultrasonic scalpel rod.

[0060] The acoustic-mechanical coupling stability model is constructed using an energy dissipation distribution function. The main control unit extracts the real-time change rate of the elastic modulus and combines it with the attenuation rate of the dry and wet cutting sound power, which is introduced as a background noise power bias constant. The model performs dimensionless processing on the mechanical distortion characteristics and acoustic impedance characteristics respectively, and then inputs them into a continuous variance distribution architecture to output continuous coefficients that characterize the stability of acoustic-mechanical energy coupling under liquid immersion boundary.

[0061] The acoustic-mechanical coupling maintenance model is as follows: In the formula, For acoustic-mechanical coupling degree; This is the initial elastic modulus; This represents the real-time rate of change of the elastic modulus. As the baseline drift rate factor; These are the reference acoustic powers for the same cutting depth in dry and wet states, respectively. This is the system's inherent noise power bias constant; These are the coupling variance coefficients; This is the acoustic impedance weighting factor.

[0062] in, (Initial elastic modulus) refers to the elastic modulus of the test load when it is not subjected to ultrasonic scalpel or in an initial steady state. It is obtained by performing material mechanics tests on the test load in advance, such as using static compression tests or dynamic mechanical analysis (DMA). (Real-time change rate of elastic modulus) represents the rate at which the elastic modulus of the test load changes over time. This reflects the dynamic changes in the mechanical properties of the test load under the action of an ultrasonic scalpel due to factors such as thermal effects, structural damage, or material phase transformation. It is obtained by real-time monitoring of the force and displacement signals of the test load and calculation based on the principles of material mechanics.

[0063] The (benchmark drift factor) is a preset reference benchmark used to measure the rate of change of the elastic modulus. It defines the maximum allowable rate or range of change of the elastic modulus under normal or acceptable working conditions. This factor can be empirically set according to the characteristics of different test load materials, the type of ultrasonic scalpel, and the test standards.

[0064] (Reference acoustic power at the same cutting depth in dry state) refers to the reference acoustic power measured when the ultrasonic scalpel cuts the test load to a specific depth in a dry environment. It is obtained by measuring the ultrasonic scalpel to a preset depth in a standard dry environment using a laser Doppler vibrometer or acoustic power meter.

[0065] The reference acoustic power at the same cutting depth in wet conditions refers to the reference acoustic power measured when the ultrasonic scalpel cuts the test load to the same depth as in dry conditions in a wet environment (e.g., with liquid immersion). It is obtained by measuring the ultrasonic scalpel cutting to a preset depth in a simulated wet environment using a hydrophone or acoustic power meter. The (system background noise power bias constant) is a constant used to compensate for the influence of inherent noise or background interference in the test system on the sound power measurement. It ensures that power signals not generated by the ultrasonic scalpel can be effectively excluded when calculating the sound power difference. This constant is determined by measuring the sound power of the test environment and taking the average value when the ultrasonic scalpel is not working or inactive.

[0066] The coupling variance coefficient is a parameter used to adjust the weights and sensitivities of various components in the acoustic-mechanical coupling model. It reflects the model's comprehensive consideration of changes in elastic modulus and differences in acoustic power. This coefficient can be adjusted according to the importance attached to mechanical and acoustic performance in actual application scenarios.

[0067] The (acoustic impedance weighting factor) is a weighting parameter used to balance the relative importance of mechanical performance variation terms and acoustic performance difference terms in the model. It allows the system to pay different degrees of attention to acoustic impedance changes caused by liquid wetting according to actual needs. This factor is empirically set based on the working characteristics of the ultrasonic scalpel in different media. By constructing an acoustic-mechanical coupling maintenance model, a quantitative evaluation of the degree of matching between the acoustic output and mechanical load state of the ultrasonic scalpel in a wet environment is realized. The main control unit receives data from the sensor array (such as force sensors and encoders of servo motors) to calculate the real-time rate of change of elastic modulus. Combined with the preset initial elastic modulus and reference drift rate factor, the mechanical modulus drift caused by thermal expansion or changes in material properties during the cutting process of the ultrasonic scalpel is quantified.

[0068] Meanwhile, by comparing the reference acoustic power at the same cutting depth under dry and wet conditions, and by introducing a system background noise power bias constant for correction, environmental noise interference can be effectively eliminated, and the true impact of liquid wetting on acoustic impedance can be accurately extracted. Finally, using the coupling variance coefficient and acoustic impedance weighting factor, the above-mentioned mechanical modulus change and acoustic power difference are exponentially weighted and fused to generate an acoustic-mechanical coupling maintenance index. This index not only reflects the acoustic-mechanical matching quality of the ultrasonic scalpel under wet conditions, but also provides a decision basis for subsequent dynamic compensation control. This model, as one of the multiple models constructed by the main control unit, works in conjunction with the thermal boundary effectiveness model and the liquid path anti-permeability isolation model to jointly generate multimodal test fidelity, thereby affecting the calculation of servo compensation time difference. Finally, the servo drive component performs dynamic force-position hybrid compensation control on the thermal expansion displacement of the ultrasonic scalpel rod, ensuring that the test process can dynamically adapt to complex physical conditions and improving the fidelity of power testing.

[0069] The multimodal test fidelity model is constructed using a multidimensional feature fusion inverse suppression function. The main control unit uses the product of thermal boundary effectiveness and acoustic-mechanical coupling consistency as the benchmark fidelity, and extracts electrical phase misalignment parameters and liquid film impedance distortion parameters as penalty excitation features. When the weighted sum of the penalty excitation features exceeds the self-consistent critical bias, the benchmark fidelity is smoothed and suppressed by sigmoid nonlinear mapping, and the global fidelity index is output.

[0070] The multimodal test fidelity model is as follows: In the formula, To ensure fidelity in multimodal testing; For thermal boundary effectiveness; For acoustic-mechanical coupling degree; This represents the real-time phase difference between voltage and current. These are the excitation voltage and the response current, respectively. The reference liquid film impedance constant; This is the self-consistent critical bias. This is the electrical misalignment penalty constant.

[0071] Multimodal test fidelity is a comprehensive evaluation metric used to quantify the overall reliability and authenticity of the test environment, mechanical coupling state, and electrical response characteristics during the power testing of medical ultrasonic scalpels. Its core function is to fuse test data from multiple independent dimensions, thereby providing a more comprehensive and accurate assessment of the test status and overcoming the limitations of single-dimensional evaluation. The fidelity value ranges from 0 to 1, with higher values ​​indicating higher reliability of the test results.

[0072] In this multimodal test fidelity model, the thermal boundary effectiveness serves as an input parameter characterizing the stability of the environment inside the test chamber. It reflects the timeliness and accuracy of temperature and humidity regulation within the sealed test chamber 2, as well as the relationship between the actual ambient temperature and the dew point temperature. This ensures the effective control of the boundary conditions of the test environment. The higher the value, the closer the test environment is to the ideal or preset state, and the less interference it has on the test results.

[0073] In this multimodal test fidelity model, the acoustic-mechanical coupling maintenance degree serves as a key input parameter characterizing the stability of the mechanical coupling state between the ultrasonic scalpel and the test load. It quantifies the influence of the rate of change of the elastic modulus of the ultrasonic scalpel and the difference in dry and wet acoustic power on the coupling state during the cutting process, ensuring the effectiveness and stability of energy transfer between the ultrasonic scalpel and the load. The higher the value, the more stable the acoustic-mechanical coupling state and the higher the energy transfer efficiency.

[0074] The real-time phase difference between voltage and current is the time or angle difference between the excitation voltage and the response current when the ultrasonic scalpel is working. This phase difference can directly reflect the electrical resonance characteristics and energy loss of the ultrasonic scalpel under a specific load (such as a liquid film). It is calculated by synchronously sampling the excitation voltage and response current signals through the analog-to-digital converter (ADC) configured in the main control unit, and then calculating the phase difference between the two signals through digital signal processing (DSP) algorithms.

[0075] Excitation voltage and response current are the voltage signal applied to the ultrasonic scalpel transducer and the current signal flowing through the transducer, respectively. These two parameters are the basis for evaluating the electrical working state of the ultrasonic scalpel. They are measured in real time by voltage and current sensors configured in the main control unit, and the analog signals are converted into digital signals for processing by the main control unit. The real-time data can reflect the instantaneous electrical load characteristics of the ultrasonic scalpel.

[0076] The reference liquid film impedance constant is a pre-set reference electrical impedance value between the ultrasonic scalpel and the liquid film load under ideal wet test conditions. This constant is used as a comparison benchmark to evaluate the degree of deviation of the electrical impedance between the ultrasonic scalpel and the liquid film load during actual testing. It is obtained through multiple experimental calibrations under standard wet conditions and is stored in the memory of the main control unit.

[0077] The self-consistent critical bias is a parameter used to adjust the output range and sensitivity of a multimodal test fidelity model. It plays a role in normalizing and regulating the nonlinear response in the model, ensuring that the fidelity value varies within a reasonable range, and balancing the electrical misalignment penalty term in the model. This bias can be optimized and adjusted using experimental data from the system under different operating conditions to make the model output fidelity more consistent with the actual situation.

[0078] The electrical misalignment penalty constant is a penalty factor used to quantify the deviation of the electrical working state of an ultrasonic scalpel from an ideal reference. Used to penalize deviations in the phase difference between voltage and current, These constants, used to penalize deviations between the actual impedance and the reference liquid film impedance, are calibrated through experiments under different electrical offset conditions and in conjunction with model optimization algorithms. This ensures that the fidelity of multimodal testing can be significantly reduced when electrical parameters become abnormal, thus reflecting the unreliability of the test.

[0079] The main control unit first acquires the thermal boundary effectiveness, which reflects the stability and control effect of the temperature and humidity environment inside the sealed test chamber 2, ensuring the authenticity of the test environment. At the same time, the main control unit acquires the acoustic-mechanical coupling stability, which quantifies the mechanical coupling stability between the ultrasonic scalpel and the test load, including the rate of change of elastic modulus and the difference in acoustic power between dry and wet states, thereby evaluating the efficiency and stability of energy transfer.

[0080] Based on this, the model further introduces the electrical resonance parameters of the ultrasonic scalpel during operation, including the real-time phase difference between voltage and current, and the excitation voltage and response current. These electrical parameters can capture the changes in the electrical impedance characteristics of the ultrasonic scalpel under liquid film load in real time, and directly reflect the energy output efficiency and working status of the ultrasonic scalpel.

[0081] To effectively integrate these electrical parameters with environmental and mechanical parameters, a nonlinear mapping function was designed for the model, and an electrical misalignment penalty constant was introduced. When the phase difference between voltage and current deviates from the ideal value, or when there is a large difference between the actual impedance and the impedance constant of the reference liquid film, these penalty constants will cause the fidelity value to decrease, thus accurately reflecting the abnormality of the electrical working state. In addition, the model also introduces a self-consistent critical bias to normalize and adjust the output of the entire model, ensuring that the output range of the multimodal test fidelity is reasonable and has good sensitivity. Through this multimodal fusion mechanism, the error caused by the fluctuation of single sensor data is eliminated, providing a high-confidence test state evaluation index.

[0082] The specific servo compensation time difference model is as follows: In the formula, The multimodal cooperative convergence factor, To compensate for time difference in the servo system; For encoder compensation trigger timing; The moment of force overload initiation; Minimum latency to the hardware limit; The relaxation factor is a non-piecewise absolute value approximation. These are the time convergence driving coefficients for fidelity and isolation, respectively; To ensure fidelity in multimodal testing; This refers to the impermeability and isolation of the liquid path.

[0083] Among them, the multimodal collaborative convergence factor It is based on the fidelity of multimodal testing and liquid path impermeability isolation The calculated weighting factor serves to comprehensively reflect the reliability of the current test environment and the state of liquid circuit isolation, providing a basis for dynamic adjustment in subsequent servo compensation time difference calculations.

[0084] Servo compensation time difference This refers to the amount of time the main control unit needs to adjust the actions of the servo drive components when performing dynamic force-position hybrid compensation control for the thermal expansion displacement of the ultrasonic scalpel. It determines the timeliness and accuracy of the compensation response, and the encoder compensation trigger time. This refers to the moment when the encoder of the servo motor detects a change in the displacement of the ultrasonic cutter bar and triggers the compensation logic to start. It can be determined by the rate of change of the displacement signal or speed signal output by the encoder in real time.

[0085] Force overload start time This refers to the moment when the force sensor detects that the contact force between the ultrasonic scalpel rod and the test load exceeds a preset threshold, indicating that an overload may occur. This can be determined by comparing the real-time force signal output by the force sensor with the preset safety threshold.

[0086] Hardware Limit Minimum Latency The relaxation factor refers to the inherent minimum time delay from receiving a command to actually executing an action in a servo drive system. It is the physical limit of the system's response speed and is a non-piecewise absolute value approximation of the relaxation factor. It is used to smoothly approximate absolute value functions in mathematical models, avoiding discontinuities during calculation, thereby improving the numerical stability and convergence of the model.

[0087] Fidelity time convergence driving coefficient and isolation time convergence driving coefficient It is used to adjust the fidelity of multimodal testing. and liquid path impermeability isolation Multimodal co-convergence factor The weighting parameters for the degree of influence can be calibrated according to actual testing needs and system characteristics to optimize the compensation effect.

[0088] Multimodal testing fidelity It is a comprehensive indicator that measures the reliability and accuracy of data from the entire testing system under current operating conditions. A higher value indicates more reliable test results. (Liquid circuit impermeability isolation) It is an indicator for evaluating the sealing performance and leak-proof capability of the negative pressure waste discharge component pipeline. The higher the value, the better the liquid path isolation effect.

[0089] By constructing a servo-compensated time-difference model, dynamic force-position hybrid compensation control of the thermal expansion displacement of the ultrasonic scalpel bar was achieved. The main control unit first utilized multimodal testing fidelity. and liquid path impermeability isolation Calculate the multimodal cooperative convergence factor This factor This comprehensively reflects the reliability of the current testing environment and the state of liquid circuit isolation, providing a weighted benchmark for subsequent compensation time difference calculations.

[0090] Next, the main control unit compensates for the trigger timing by introducing an encoder. With the onset of force overload The difference, combined with the hardware's minimum latency limit Non-piecewise absolute value approximation relaxation factor Calculate the servo compensation time difference It can measure the fidelity of multimodal testing in real time. and liquid path impermeability isolation Data is used to dynamically adjust the response timing of servo drive components.

[0091] Specifically, when multimodal test fidelity High and liquid path impermeability isolation When it is good, the multimodal cooperative convergence factor This will cause the servo to compensate for time difference. The calculation is more sensitive to changes in the displacement and force of the ultrasonic scalpel rod; conversely, if the fidelity or isolation is low, the factor... Certain adjustments will be introduced to make the compensation strategy more robust or conservative. The main control unit can send precise commands to the servo drive component to achieve dynamic force-position hybrid compensation for the thermal expansion displacement of the ultrasonic scalpel bar. Thus, when the ultrasonic scalpel bar is displaced due to thermal expansion, the servo drive component can perform precise displacement compensation in a timely manner.

[0092] The constants and biases contained in each model constitute the undetermined parameter vector; the main control unit internally contains the parameter vector obtained by offline solution through the global parameter error minimization iterative model; the iterative model is calibrated by calculating the deviation loss between the system output fidelity and the target fidelity under the sample and applying a regularization penalty term to prevent overfitting.

[0093] The system constants in each model constitute the vector of undetermined parameters. The main control unit internally contains parameter vectors obtained through offline solution of the following calibration loss model. : In the formula, This represents the mean squared loss value of the deviation. These are the calculated value and the target fidelity value, respectively. The total number of standard samples; is the regularized regression coefficient.

[0094] Among them, the system constants in each model constitute the undetermined parameter vector. These system constants are pre-defined values ​​in the model that have fixed meanings under specific physical or engineering contexts. They collectively determine the model's behavior and output. (The undetermined parameter vector...) This refers to the set of system constants, which are usually unknown or require optimization in the early stages of model building. These system constants may include, but are not limited to, physical constants (such as gravitational acceleration). Waste liquid density ), empirical coefficients (such as environmental hysteresis weight constant) Pipeline flow resistance nonlinear damping coefficient Electrical misalignment penalty constant ), and calibration parameters (such as reference tolerance time constant) System noise floor power bias constant Hardware Limit Minimum Latency ).

[0095] The aforementioned constants collectively determine the specific calculation logic and output results of the thermal boundary effectiveness model, the liquid path anti-seepage isolation model, the acoustic-mechanical coupling maintenance model, the multimodal test fidelity model, and the servo compensation time difference model.

[0096] The main control unit internally contains parameter vectors obtained through offline solution of the calibration loss model. The main control unit is the control core of the entire device, responsible for data processing, model calculation and control command output. Internal solidification means that these parameters are determined and stored in the non-volatile memory of the main control unit, such as flash memory, EEPROM or ROM, before the device leaves the factory or within a specific maintenance cycle, so that they can be directly called at runtime without real-time calculation or external input.

[0097] Offline solution refers to the process of determining parameters before the device is actually running (online). It is usually carried out in a laboratory environment through a special calibration process and algorithm. Offline solution can use a variety of optimization algorithms, such as gradient descent, least squares, genetic algorithm or particle swarm optimization algorithm, etc. Iterative calculation is used to find the parameter vector that minimizes the loss function. The solidification method can be to directly burn the solved parameters into the firmware of the main control unit, or store them in a configuration file or database accessible by the main control unit.

[0098] Calibration loss model It is used to evaluate parameter vectors The mathematical function for determining performance aims to minimize this loss value, thereby finding the optimal parameter vector. This model consists of two parts: the first part is the mean squared error term, which measures the multimodal test fidelity calculated by the model. Compared with the preset target fidelity value The first part is the deviation between the two; the second part is the regularization term, which is used to penalize excessively large parameter values, prevent the model from overfitting, and improve the model's generalization ability. The mean squared error term is obtained by calculating the average of the sum of squares of the differences between the calculated values ​​and the target values ​​for each standard sample. The regularization term is usually in the form of the L2 norm (i.e., the square root of the sum of squares of the elements of the parameter vector) and multiplied by a regularization regression coefficient. To control its contribution to the total loss, during the offline solution process, the parameter vector is adjusted. This makes the loss function It reaches the minimum value.

[0099] By introducing an offline calibration mechanism, the problem of blindly configuring model parameters is solved. Before the actual operation of the device, offline solutions are performed using a standard sample set. By constructing a calibration loss model that includes a mean squared loss term and a regularization term, the system constants are accurately optimized.

[0100] By minimizing the mean square error between the calculated fidelity and the target fidelity, the accuracy of the model output is ensured. Simultaneously, the introduction of regularized regression coefficients effectively prevents overfitting during parameter fitting, enhancing the generalization ability and stability of the system constants under different operating conditions. This allows the testing device to calculate multimodal test fidelity in real time based on the calibrated optimal parameter vector, providing reliable data support for subsequent servo compensation control. This scheme, together with the main control unit, constructs a thermal boundary effectiveness model, a liquid path anti-seepage isolation model, and an acoustic-mechanical coupling maintenance model, and combines dynamic mechanical modulus and reference acoustic power to construct an acoustic-mechanical coupling model. The combined stability model further integrates the thermal boundary effectiveness, acoustic-mechanical coupling stability, and electrical resonance parameters to generate multimodal test fidelity. Finally, based on the multimodal test fidelity and the liquid circuit anti-permeability isolation, the servo compensation time difference is output. This is combined with the function of dynamic force-position hybrid compensation control of the thermal expansion displacement of the ultrasonic scalpel rod through the servo drive component. This ensures that the system constants used by the main control unit in real-time model calculation and servo compensation control are accurately optimized and verified, thereby significantly improving the accuracy and reliability of model calculation. This enables the servo compensation control to more accurately perform dynamic force-position hybrid compensation control of the thermal expansion displacement of the ultrasonic scalpel rod.

[0101] The real-time rate of change of the elastic modulus is obtained through a dynamic differential mapping algorithm; the main control unit synchronously acquires real-time force and displacement signals, calculates the first derivative of each with respect to time, and, in conjunction with the initial contact geometry of the test load, calculates and outputs the transient rate of change of the force-displacement curve gradient in real-time closed-loop calculation.

[0102] The main control unit is based on real-time force signals. and real-time displacement signal The real-time rate of change of the elastic modulus is obtained by closing the loop using the following dynamic calculus mapping formula. : In the formula, To test the initial thickness of the load under stress; For effective contact cross-sectional area; These are the first derivatives of the force signal and displacement signal with respect to time, respectively.

[0103] The main control unit processes force signals in real time. and displacement signal The real-time rate of change of the elastic modulus is calculated based on the preset dynamic calculus mapping formula. Real-time force signal This indicates the instantaneous force condition of the test load under the action of the ultrasonic scalpel, which can be collected in real time by the force sensor set at the bottom of the load fixture 6 and transmitted to the main control unit.

[0104] Real-time displacement signal This represents the instantaneous deformation or displacement of the test load under stress over time. It can be the displacement information fed back by the encoder of the servo motor. These two signals are the raw input data for calculating the real-time rate of change of the elastic modulus using the dynamic calculus mapping formula. They reflect the dynamic mechanical interaction process between the ultrasonic scalpel and the test load.

[0105] The dynamic calculus mapping formula is the core calculation logic of this scheme, and it is based on real-time force signals. and real-time displacement signal and its first derivative with respect to time Combined with the initial geometric parameters of the test load (Initial stress thickness) and (Effective contact cross-sectional area) is used to derive the real-time rate of change of elastic modulus. By performing differential calculations on the instantaneous mechanical state, it is possible to capture the minute and rapid changes in the elastic modulus of the loaded material during ultrasonic vibration and cutting, thereby achieving accurate characterization of the dynamic mechanical properties of the material.

[0106] Closed-loop acquisition refers to the ability of the main control unit to continuously and in real-time acquire force and displacement signals, and to continuously calculate and update the real-time rate of change of the elastic modulus. This ensured The calculation results can reflect the actual dynamic mechanical state of the test load in a timely manner and can be used immediately for subsequent model updates and control decisions. For example, the main control unit can continuously monitor sensor data at a high sampling rate and complete the formula calculation in each sampling cycle, thereby forming a continuous feedback loop, which makes the acquisition process of the elastic modulus change rate highly real-time and responsive.

[0107] The main control unit continuously receives real-time force signals from the force sensor at the bottom of the load clamp 6. and real-time displacement signals provided by servo motor encoders or independent displacement sensors. These signals reflect the dynamic mechanical interaction between the ultrasonic scalpel and the test load during the simulated cutting process.

[0108] The main control unit then processes these real-time signals at high speed, calculating the first derivative of the force signal with respect to time using a numerical differentiation algorithm. and the first derivative of the displacement signal with respect to time Based on this, the main control unit combines these real-time derivatives with the original signal. and the preset initial geometric parameters of the test load. (Initial stress thickness) and Substituting the effective contact cross-sectional area into the dynamic calculus mapping formula allows for the real-time, continuous calculation of the rate of change of the elastic modulus of the test load. This calculation process is performed in a closed loop, meaning the system can continuously update based on the latest sensor data. The value ensures accurate tracking of the dynamic mechanical properties of the load material.

[0109] In this way, the real-time rate of change of the elastic modulus is obtained. The initial value of the elastic modulus is directly input into the acoustic-mechanical coupling maintenance model. In the basic scheme, the acoustic-mechanical coupling maintenance model has already considered the initial value of the elastic modulus. and benchmark drift factor However, it lacks the perception of dynamic and instantaneous changes in the elastic modulus.

[0110] By providing real-time This allows the acoustic-mechanical coupling maintenance model to more accurately reflect the actual acoustic-mechanical coupling state between the ultrasonic scalpel and the load during wet wetting and dynamic cutting processes. For example, when the ultrasonic scalpel cuts tissues of different hardness or wettability, the elastic modulus of the load changes rapidly. This change is achieved through… Captured.

[0111] Furthermore, a more precise acoustic-mechanical coupling maintenance This will directly improve the fidelity of multimodal testing. The accuracy of calculations and the fidelity of multimodal testing. Integrating thermal boundary effectiveness Acoustic-mechanical coupling degree And the accuracy of the electrical resonance parameters is crucial for the final output servo compensation time difference. It is of utmost importance.

[0112] Therefore, the real-time rate of change of elastic modulus is obtained through closed-loop control. This enables the entire ultrasonic scalpel power testing device to more accurately evaluate the actual output performance of the ultrasonic scalpel, and provides a more reliable basis for the servo drive component to perform dynamic force-position hybrid compensation control on the thermal expansion displacement of the ultrasonic scalpel rod. This effectively solves the problem of insufficient perception of material properties in dynamic cutting simulation by traditional methods, and significantly improves the accuracy and real-time performance of the test.

[0113] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A medical ultrasonic scalpel power testing device, characterized in that: include: The cabin is divided into an upper sealed test chamber and a lower dry drive chamber by a partition; The sealed test chamber contains a temperature and humidity control assembly, a dynamic dripping assembly facing the test load, and a negative pressure waste discharge assembly connected to an external pump. The sealed test chamber is also equipped with an anti-fog observation window; The servo drive assembly located in the drying drive chamber includes a servo motor and a linear transmission mechanism. Its output end extends through the rotary seal of the partition into the sealing test chamber and is connected to the load clamp. The sensor array includes a temperature and humidity sensor in the sealed test chamber, a dynamic pressure sensor in the negative pressure waste discharge assembly, an encoder of the servo motor, a force sensor at the bottom of the load fixture, and an impedance spectrum sensor below the test load. The main control unit is communicatively connected to the temperature and humidity control component, the dynamic dripping component, the servo drive component, and the sensor array, respectively. The main control unit is configured to: construct a thermal boundary effectiveness model and a liquid path anti-seepage isolation model based on the data from the sensor array, and construct an acoustic-mechanical coupling maintenance model by combining the dynamic mechanical modulus and the reference acoustic power; further, fuse the thermal boundary effectiveness, acoustic-mechanical coupling maintenance, and electrical resonance parameters to generate multimodal test fidelity; Finally, based on the multimodal test fidelity and the liquid path impermeability isolation, the servo compensation time difference is used to dynamically control the thermal expansion displacement of the ultrasonic scalpel rod through the servo drive component.

2. The medical ultrasonic scalpel power testing device according to claim 1, characterized in that: The thermal boundary effectiveness model is constructed based on a nonlinear asymptotic convergence function; The main control unit calculates the time lag penalty term based on the ratio of the time taken to achieve the humidity standard in the sealed test chamber to the benchmark time, and suppresses the risk of condensation phase change by smoothing threshold mapping based on the ratio of the difference between the actual measured temperature and the dew point temperature to the benchmark temperature difference, and outputs a normalized effectiveness coefficient.

3. The medical ultrasonic scalpel power testing device according to claim 2, characterized in that: The dew point temperature is obtained in real time through a nonlinear mapping relationship of thermodynamic state. The main control unit extracts the combined characteristics of the actual measured temperature and real-time relative humidity, and performs continuous algebraic conversion by combining the preset vaporization constant and absolute zero conversion constant to avoid segmented condition judgment and dynamically output the dew point temperature that reflects the critical point of phase change in the cabin.

4. The medical ultrasonic scalpel power testing device according to claim 3, characterized in that: The liquid path impermeability isolation model is constructed using a fluid dynamics saturated damping function. The main control unit uses the difference between the peak and valley pressure in the pipeline as the pulsation disturbance and the hydrostatic pressure determined by the density of the waste liquid and the height of the waste discharge pipeline as the critical threshold for impermeability. The model calculates the ratio of the disturbance to the critical threshold and outputs a safety factor characterizing the unidirectional isolation state of the waste discharge pipeline through a boundary-constrained nonlinear damping mapping.

5. The medical ultrasonic scalpel power testing device according to claim 4, characterized in that: The acoustic-mechanical coupling maintenance model is constructed using an energy dissipation distribution function; The main control unit extracts the real-time change rate of the elastic modulus and combines it with the attenuation rate of the dry and wet cutting sound power, which is based on the background noise power bias constant. The model performs dimensionless processing on the mechanical distortion characteristics and acoustic impedance characteristics, and then inputs them into a continuous variance distribution architecture to output continuous coefficients that characterize the stability of acoustic-mechanical energy coupling under liquid immersion boundary conditions.

6. The medical ultrasonic scalpel power testing device according to claim 5, characterized in that: The multimodal test fidelity model is constructed using a multidimensional feature fusion inverse suppression function; The main control unit uses the product of the thermal boundary effectiveness and the acoustic-mechanical coupling maintenance as the benchmark fidelity, and extracts the electrical phase misalignment parameters and liquid film impedance distortion parameters as penalty excitation features. When the weighted sum of the penalty incentive features exceeds the self-consistent critical bias, the baseline fidelity is smoothed and suppressed by an sigmoid nonlinear mapping, and a global fidelity index is output.

7. The medical ultrasonic scalpel power testing device according to claim 6, characterized in that: The servo compensation time difference model uses an asymptotic approximation algorithm with lower bound constraints to output terminal control commands. Its specific nonlinear mathematical and physical model is as follows: In the formula, It is the multimodal collaborative convergence factor; To compensate for time difference in the servo system; The encoder compensation trigger time; This refers to the start time of the sudden overload change in the force sensor. Minimize the latency to the limit of servo drive hardware; The relaxation factor is a non-piecewise absolute value approximation. These are the time convergence driving coefficients; Multimodal testing fidelity; Liquid path impermeability isolation.

8. The medical ultrasonic scalpel power testing device according to claim 7, characterized in that: The constants and biases contained in each model constitute the undetermined parameter vector; The main control unit internally contains the parameter vector obtained by offline solution through a global parameter error minimization iterative model. The iterative model is calibrated by calculating the deviation loss between the system output fidelity and the target fidelity under the sample and applying a regularization penalty term to prevent overfitting.

9. A medical ultrasonic scalpel power testing device according to claim 8, characterized in that: The real-time rate of change of the elastic modulus is obtained through a dynamic differential mapping algorithm. The main control unit synchronously acquires real-time force and displacement signals, calculates their first derivatives with respect to time, and, in conjunction with the initial contact geometry of the test load, calculates and outputs the transient rate of change of the force-displacement curve gradient in real-time closed-loop calculation.

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