An ultrasonic knife head vibration energy efficiency evaluation method based on laser vibration measurement

Abstract

This invention belongs to the field of vibration testing technology and vibration signal analysis, specifically a method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement. This method is based on a given value f of the ultrasonic scalpel head vibration frequency. n Sampling parameters are set, and based on these parameters, a laser vibrometer is used to collect the axial vibration signal of the ultrasonic scalpel head during operation. Power spectrum analysis is performed on the collected vibration signal to obtain a power spectrum diagram. The ultrasonic scalpel head vibration frequency f is then selected from the power spectrum diagram. n Find the maximum frequency peak near a given value and record the x and y coordinates of this peak (f). nmax ,P nmax Plot a line with P as the vertical axis in the power spectrum. nmax A straight line of -3dB is obtained to obtain two frequency values ​​f1 and f2 corresponding to the half power value; the vibration energy efficiency evaluation index of the ultrasonic scalpel is calculated. Steps a to e are executed multiple times within different time ranges when the ultrasonic scalpel is working to obtain multiple ultrasonic scalpel vibration energy efficiency evaluation values. By observing the changes in this value, the vibration energy efficiency of the ultrasonic scalpel head during operation is evaluated.

Description

Technical Field

[0001] This invention relates to the field of vibration testing technology and vibration signal analysis, specifically to a method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement. Background Technology

[0002] When an ultrasonic scalpel is in operation, the energy efficiency of the vibration generated axially by the scalpel tip is a key factor in ensuring the quality of the equipment's operation. Low vibration energy efficiency will result in the ultrasonic scalpel failing to achieve the desired shearing and coagulation effects, and in severe cases, may pose surgical risks to the patient. The vibration of the ultrasonic scalpel and its confined measurable space mean that it is impossible to use sensors to collect its vibration signals through contact.

[0003] Currently, no organization or individual has conducted research on the vibration energy efficiency of ultrasonic scalpel heads, nor are there effective technical means to evaluate the vibration energy efficiency of ultrasonic scalpel heads. Summary of the Invention

[0004] This invention aims to provide a method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement, using the vibration energy efficiency of the ultrasonic scalpel as an evaluation index.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement includes the following steps:

[0007] Step a: Based on the given value f of the ultrasonic scalpel head vibration frequency. n Set sampling parameters, and based on the set sampling parameters, use a laser vibrometer to collect the axial vibration signal of the ultrasonic scalpel head during current operation;

[0008] Step b: Perform power spectrum analysis on the collected vibration signal, and convert the vertical axis of the power spectrum into decibels during the process to obtain the power spectrum.

[0009] Step c: Select the ultrasonic scalpel head vibration frequency f from the power spectrum obtained in step b. n Record the maximum frequency peak value near a given value, and record the horizontal and vertical coordinates of this peak value (f). nmax ,P nmax );

[0010] Step d: Plot a line with P as the vertical axis in the power spectrum obtained in step b. nmax A straight line of -3dB yields two frequency values ​​f1 and f2 corresponding to the half-power value;

[0011] Step e: Based on the efficiency formula, obtain the vibration energy efficiency evaluation index formula for ultrasonic scalpel during operation. Using this formula, the current vibration energy efficiency evaluation value of ultrasonic scalpel can be calculated.

[0012]

[0013] In the formula Q c f represents the vibration energy efficiency of an ultrasonic scalpel. n f represents the setpoint of the ultrasonic scalpel head vibration frequency. max The x-axis of the maximum frequency peak near the given value of the ultrasonic scalpel head vibration frequency is selected, and f2 and f1 are the two frequency values ​​corresponding to the half power value;

[0014] Step f: Repeat steps a to e multiple times during different time periods when the ultrasonic scalpel is working to obtain multiple ultrasonic scalpel vibration energy efficiency evaluation values. Observe the changes in these values ​​to complete the evaluation of the vibration energy efficiency of the ultrasonic scalpel head during operation.

[0015] Furthermore, step a involves calculating the root mean square value of the collected vibration signal to obtain the effective value x of the acquired signal. rms This value is used to exclude invalid acoustic cutter head axial vibration signals collected.

[0016] Furthermore, the method for power spectrum analysis of the vibration signal in step b includes various methods capable of power spectrum analysis, including but not limited to periodogram method, correlation function method, etc.

[0017] This invention provides a method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibrometer. The method utilizes a laser vibrometer for non-contact vibration signal acquisition, calculates the power spectrum of the acquired vibration signals, and derives a formula for evaluating the vibration energy efficiency of the ultrasonic scalpel during operation through power spectrum analysis. By repeatedly executing steps a to e within different time ranges during ultrasonic scalpel operation, multiple ultrasonic scalpel vibration energy efficiency evaluation values ​​are obtained. Observing the changes in these values ​​allows for the evaluation of the vibration energy efficiency of the ultrasonic scalpel head during operation.

[0018] Compared with existing technologies, this invention uses vibration energy efficiency as an evaluation index. Since vibration energy efficiency can effectively shield the measurement error and human error of the original time domain signal, its evaluation accuracy is higher. Attached Figure Description

[0019] Figure 1 This illustrates the specific implementation process of the present invention;

[0020] Figure 2 The power spectrum diagram described in this invention and the vibration frequency f of a certain type of ultrasonic scalpel head are shown. n The maximum frequency peak near a given value, and the x and y coordinates of this peak (f nmax ,P nmax ), P nmax A schematic diagram of the -3dB straight line and the two frequency values ​​f1 and f2 corresponding to the half power value. Detailed Implementation

[0021] The present invention will now be described with reference to the accompanying drawings and embodiments. Those skilled in the art should understand that the accompanying drawings provided herein...

[0022] All of these are for illustrative purposes, and the accompanying drawings are not necessarily drawn to scale.

[0023] Unless the context explicitly requires it, words such as "comprising" or "including" should be used throughout the specification and claims.

[0024] When interpreted as encompassing rather than exhaustive or exclusive: that is, meaning "includes but not limited to".

[0025] like Figure 1 As shown in the figure, this embodiment provides a method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement, which includes the following steps:

[0026] Step a: Based on the given value f of the ultrasonic scalpel head vibration frequency. n Sampling parameters are set, and based on these parameters, a laser vibrometer is used to collect the axial vibration signal of the ultrasonic scalpel head during operation. The laser vibrometer used in this embodiment is as follows: Figure 2 As shown, the ultrasonic scalpel structure has set sampling parameters including sampling frequency and sampling time, where the sampling frequency is 2.56–4f. n The sampling time is greater than 1 second. This range of frequency and time is chosen as the setting parameters to meet the sampling theorem requirements and obtain a frequency resolution of less than 1 Hz.

[0027] The collected vibration signals include at least one of vibration acceleration, vibration velocity, and vibration displacement. When the vibration signal is vibration acceleration, the vibration displacement is obtained by two integrations. When the vibration signal is vibration velocity, the vibration displacement is obtained by one integration.

[0028] Step b: Perform power spectrum analysis on the acquired vibration signal, converting the ordinate of the power spectrum graph to decibels during this process to obtain the power spectrum graph. Methods for power spectrum analysis of the acquired vibration signal include various methods capable of performing power spectrum analysis, including but not limited to the periodogram method and the correlation function method. This embodiment preferably uses the periodogram method. It should be noted that in this embodiment, the power spectrum graph obtained after power spectrum analysis uses decibels, a commonly used unit of intensity in the field of vibration. If the ordinate is not converted to decibels, the power spectrum analysis result should be considered essentially unchanged.

[0029] Step c: Select the ultrasonic scalpel head vibration frequency f from the power spectrum obtained in step b. nRecord the maximum frequency peak value near a given value, and record the horizontal and vertical coordinates of this peak value (f). nmax ,P nmax ).

[0030] Step d: Plot a line with P as the vertical axis in the power spectrum obtained in step b. nmax The straight line at -3dB yields two frequency values, f1 and f2, corresponding to the half-power value. In vibration power spectrum analysis, half-power refers to the result after subtracting 3dB; this result is also called the half-power spectrum.

[0031] Step e: Based on the efficiency formula, obtain the vibration energy efficiency evaluation index formula for ultrasonic scalpel during operation. Using this formula, the current vibration energy efficiency evaluation value of ultrasonic scalpel can be calculated.

[0032]

[0033] In the formula Q c f represents the vibration energy efficiency of an ultrasonic scalpel. n f represents the setpoint of the ultrasonic scalpel head vibration frequency. max The x-axis of the maximum frequency peak near the given value of the ultrasonic scalpel head vibration frequency is selected, and f2 and f1 are the two frequency values ​​corresponding to the half power value;

[0034] Step f: Repeat steps a to e multiple times during different time periods when the ultrasonic scalpel is working to obtain multiple ultrasonic scalpel vibration energy efficiency evaluation values. Observe the changes in these values ​​to complete the evaluation of the vibration energy efficiency of the ultrasonic scalpel head during operation.

[0035] To make the evaluation more accurate, the above-mentioned method for evaluating the vibration energy efficiency of ultrasonic scalpel heads based on laser vibration measurement also calculates the root mean square value of the collected vibration signal to obtain the effective value x of the acquired signal. rms This ensures the validity of the acquired acoustic cutter head axial vibration signal.

Claims

1. A method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement, characterized in that, Includes the following steps: Step a: Based on the given value of the ultrasonic scalpel head vibration frequency. Set sampling parameters, and based on the set sampling parameters, use a laser vibrometer to collect the axial vibration signal of the ultrasonic scalpel head during current operation; Step b: Perform power spectrum analysis on the collected vibration signal, and convert the vertical axis of the power spectrum into decibels during the process to obtain the power spectrum. Step c: Select the ultrasonic scalpel head vibration frequency from the power spectrum obtained in step b. Record the maximum frequency peak value near a given value, and record the horizontal and vertical coordinates of this peak value. ; Step d: Plot a line on the vertical axis of the power spectrum obtained in step b. By drawing a straight line, we can obtain the two frequency values ​​corresponding to the half-power value. and ; Step e: Based on the efficiency formula, obtain the vibration energy efficiency evaluation index formula for ultrasonic scalpel during operation. Using this formula, the current vibration energy efficiency evaluation value of ultrasonic scalpel can be calculated. In the formula Q c f represents the vibration energy efficiency of an ultrasonic scalpel. n f represents the setpoint of the ultrasonic scalpel head vibration frequency. nmax The x-axis of the maximum frequency peak near the given value of the ultrasonic scalpel head vibration frequency is selected, and f2 and f1 are the two frequency values ​​corresponding to the half power value; Step f: Repeat steps a to e multiple times during different time periods when the ultrasonic scalpel is working to obtain multiple ultrasonic scalpel vibration energy efficiency evaluation values. Observe the changes in these values ​​to complete the evaluation of the vibration energy efficiency of the ultrasonic scalpel head during operation.

2. The method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement according to claim 1, characterized in that: Step a further involves calculating the root mean square value of the collected vibration signal to obtain the effective value of the acquired signal. This value is used to exclude invalid acoustic cutter head axial vibration signals collected.

3. The method for evaluating the vibration energy efficiency of an ultrasonic scalpel head based on laser vibration measurement according to claim 1 or 2, characterized in that: The method for power spectrum analysis of the vibration signal in step b is either the periodogram method or the correlation function method.

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