Drilling tool dynamic measurement signal frequency detection method

Abstract

The invention discloses a drilling tool dynamic measurement signal frequency detection method. The method comprises the following steps: collecting drilling tool dynamic signal data; performing large-frequency signal detection on the drilling tool dynamic signal data through a variable-scale tri-stable chaotic system; all-phase frequency detection of the drilling tool dynamic signal data is carried out through an array tri-stable chaotic system; and combining the variable-scale tri-stable chaotic system and the array tri-stable chaotic system, and detecting the dynamic signal data of the drilling tool at the same time. The array tri-stable chaos detection system is not influenced by the initial phase angle of the drilling tool measurement signal, and the frequency detection problem of the drilling tool measurement signal is solved. The frequency detection problem of the drilling tool measurement signal in the frequency mixing state is effectively solved through the phase change technology.

Description

Technical Field

[0001] The present invention relates to the technical field of signal detection, and particularly to a method for detecting the frequency of dynamic measurement signals of drill tools. Background Art

[0002] Digital filters based on time-frequency analysis were first applied to the noise suppression of dynamic measurement signals of downhole drilling tools. The mud pulse signals were denoised by using FIR digital filters through a ground decoding system. However, in the actually collected sensor signals, due to the diversity of interference sources, the frequency distribution of noise signals is very complex, and there will inevitably be parts that overlap with the frequencies of the signals to be measured. Therefore, while suppressing the noise, the useful signals will inevitably be damaged, or even lead to invalid dynamic measurement of the downhole drilling tools.

[0003] A non-linear model for measuring the attitude of drill tools based on quaternions is used, and the unscented Kalman filtering algorithm is applied to filter out noise interference. However, affected by the complex downhole drilling and production environment, there are many uncertainties in the modeling process, such as sudden changes in system parameters, instantaneous interference, unknown noise statistical characteristics, unknown measurement drift, etc., resulting in a decrease in the estimation accuracy of the unscented Kalman filter, and even filter divergence, thus causing the optimal estimation to be invalid. Therefore, the dynamic measurement method based on multi-sensor combined measurement and optimal estimation algorithm has inevitable defects and limitations.

[0004] The phase state change of the existing three-stable chaotic system can successfully detect weak signals under a strong noise background. However, when it is applied to the frequency detection of dynamic measurement signals of downhole drilling tools, the angular frequency of the signal to be measured is not a constant value, but continuously changes based on the rotation speed of the drill tool. The change in the driving signal frequency will also change the critical amplitude when the system undergoes a phase change, causing difficulties in the application of the three-stable chaotic system for frequency detection; when the angular frequency of the driving signal is too large, it is difficult for the system to exhibit chaos and large-scale periodic states, resulting in poor dynamic response characteristics of the system. When the drill tool is drilling normally, the dynamic response characteristics of the system deteriorate, seriously affecting the accuracy and feasibility of frequency detection. Summary of the Invention

[0005] The embodiments of the present invention provide a method for detecting the frequency of dynamic measurement signals of drill tools, which is used to solve the problems existing in the prior art when applying the three-stable chaotic system to the frequency detection of dynamic measurement signals of downhole drilling tools. The angular frequency of the signal to be measured is not a constant value, but continuously changes based on the rotation speed of the drill tool. The change in the driving signal frequency will also change the critical amplitude when the system undergoes a phase change, causing difficulties in the application of the three-stable chaotic system for frequency detection; when the angular frequency of the driving signal is too large, it is difficult for the system to exhibit chaos and large-scale periodic states, resulting in poor dynamic response characteristics of the system. When the drill tool is drilling normally, the dynamic response characteristics of the system deteriorate, seriously affecting the accuracy and feasibility of frequency detection.

[0006] On the one hand, an embodiment of the present invention provides a method for detecting the frequency of a dynamic measurement signal of a drill string, including: Collecting dynamic signal data of the drill string; Detecting large-frequency signals of the dynamic signal data of the drill string through a variable-scale three-stable chaotic system; Performing all-phase frequency detection of the dynamic signal data of the drill string through an array three-stable chaotic system; Combining the variable-scale three-stable chaotic system and the array three-stable chaotic system to simultaneously detect the dynamic signal data of the drill string.

[0007] In a possible implementation manner, the detecting large-frequency signals of the dynamic signal data of the drill string through a variable-scale three-stable chaotic system includes: Performing data reconstruction on the dynamic signal data of the drill string to obtain a reconstructed signal; Inputting the reconstructed signal into the variable-scale three-stable chaotic system for iterative calculation; Identifying the frequency of the reconstructed signal according to the change of the output phase state of the variable-scale three-stable chaotic system.

[0008] In a possible implementation manner, performing data reconstruction on the dynamic signal data of the drill string to obtain a reconstructed signal includes: Introducing a variable-scale coefficient into the dynamic signal data of the drill string to restore the angular frequency value of the dynamic signal data of the drill string to be measured; Realizing the frequency reconstruction of the dynamic signal data of the drill string by adjusting the step size of numerical calculation.

[0009] In a possible implementation manner, the performing all-phase frequency detection of the dynamic signal data of the drill string through an array three-stable chaotic system includes: Expanding the three-stable chaotic system into an array three-stable chaotic system by adjusting the initial phase angle; Substituting the dynamic signal data of the drill string into the array three-stable chaotic system to obtain the all-phase frequency of the dynamic signal data of the drill string to be measured.

[0010] In a possible implementation manner, the combining the variable-scale three-stable chaotic system and the array three-stable chaotic system to simultaneously detect the dynamic signal data of the drill string includes: Obtaining an array three-stable chaotic system by setting the initial phase angle of the dynamic signal data of the drill string; Inputting the dynamic signal data of the drill string to be measured and noise into the array three-stable chaotic system; Reconstructing the angular frequency and sampling frequency of the dynamic signal data through the variable-scale coefficient; Solving the array three-stable chaotic system through the reconstructed calculation step size; Adjust the variable scale coefficient to complete the detection of the drill string dynamic signal data.

[0011] In a possible implementation, the adjusting the variable scale coefficient to complete the detection of the drill string dynamic signal data includes: Observe the output phase trajectory of the array triple-stable chaotic system after adjusting the variable scale coefficient; Determine the angular frequency of the drill string dynamic signal data according to the output phase trajectory and the value of the variable scale coefficient.

[0012] In a possible implementation, expanding the triple-stable chaotic system into an array triple-stable chaotic system by adjusting the initial phase angle is to divide the initial phase angle into three intervals and substitute them into the expression of the triple-stable chaotic system to obtain the array triple-stable chaotic system composed of three different driving equations.

[0013] A method for detecting the frequency of a drill string dynamic measurement signal in the present invention has the following advantages: (1) Through the array triple-stable chaotic detection system, it is not affected by the initial phase angle of the drill string measurement signal, and solves the problem of frequency detection of the drill string measurement signal.

[0014] (2) Effectively solve the problem of frequency detection of the drill string measurement signal in the mixed frequency state through the phase transition technology. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 It is a flowchart of a method for detecting the frequency of a drill string dynamic measurement signal provided by an embodiment of the present application; Figure 2 It is a diagram showing the overall change of the state of the solution of a typical triple-stable chaotic system of a method for detecting the frequency of a drill string dynamic measurement signal provided by an embodiment of the present application with the amplitude; Figure 3 It is a diagram showing the partial change of the state of the solution of a typical triple-stable chaotic system of a method for detecting the frequency of a drill string dynamic measurement signal provided by an embodiment of the present application from chaos to large-scale period with the amplitude; Figure 4 It is a diagram of the chaotic state of the output phase state of a typical triple-stable chaotic system of a method for detecting the frequency of a drill string dynamic measurement signal provided by an embodiment of the present application; Figure 5The large-scale periodic state diagram of the output phase state of the typical three-stable chaotic system of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application; Figure 6 The schematic diagram of the detectable window corresponding to the initial phase angle of the array three-stable chaotic system of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application; Figure 7 The technical solution flow chart of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application; Figure 8 The trajectory diagram of the output phase of the array three-stable chaotic system without the signal to be measured of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application; Figure 9 The trajectory diagram of the output phase of the array three-stable chaotic system with K = 1 and γ = -120° of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application; Figure 10 The trajectory diagram of the output phase of the array three-stable chaotic system with K = 10 and γ = 0° of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application; Figure 11 The trajectory diagram of the output phase of the array three-stable chaotic system with K = 1 and γ = 120° of the solution of the typical three-stable chaotic system for the frequency detection method of the drill string dynamic measurement signal provided by the embodiment of the present application. Specific implementation manners

[0017] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] Figure 1 The flow schematic diagram of a frequency detection method for drill string dynamic measurement signals provided by an embodiment of the present invention; an embodiment of the present invention provides a frequency detection method for drill string dynamic measurement signals, including: Collect drill string dynamic signal data; Perform large-frequency signal detection on the drill string dynamic signal data through a variable-scale three-stable chaotic system; Perform full-phase frequency detection on the drill string dynamic signal data through an array three-stable chaotic system; Combine the variable-scale three-stable chaotic system and the array three-stable chaotic system to simultaneously detect the drill string dynamic signal data.

[0019] The detection of large-frequency signals of the drill string dynamic signal data by the variable-scale three-stable chaotic system includes: Perform data reconstruction on the drill string dynamic signal data to obtain a reconstructed signal; Input the reconstructed signal into the variable-scale three-stable chaotic system for iterative calculation; Identify the frequency of the reconstructed signal according to the change in the phase state output by the variable-scale three-stable chaotic system.

[0020] Performing data reconstruction on the drill string dynamic signal data to obtain a reconstructed signal includes: Introduce a variable-scale coefficient into the drill string dynamic signal data to restore the angular frequency value of the drill string dynamic signal data to be measured; Realize the frequency reconstruction of the drill string dynamic signal data by adjusting the step size of numerical calculation.

[0021] The all-phase frequency detection of the drill string dynamic signal data by the array three-stable chaotic system includes: Expand the three-stable chaotic system into an array three-stable chaotic system by adjusting the initial phase angle; Substitute the drill string dynamic signal data into the array three-stable chaotic system to obtain the all-phase frequency of the drill string dynamic signal data to be measured.

[0022] The combination of the variable-scale three-stable chaotic system and the array three-stable chaotic system to simultaneously detect the drill string dynamic signal data includes: Obtain an array three-stable chaotic system by setting the initial phase angle of the drill string dynamic signal data; Input the drill string dynamic signal data to be measured and noise into the array three-stable chaotic system; Reconstruct the angular frequency and sampling frequency of the dynamic signal data through the variable-scale coefficient; Solve the array three-stable chaotic system through the reconstructed calculation step size; Adjust the variable-scale coefficient to complete the detection of the drill string dynamic signal data.

[0023] The adjustment of the variable-scale coefficient to complete the detection of the drill string dynamic signal data includes: Observe the output phase trajectory of the array three-stable chaotic system after adjusting the variable-scale coefficient; Determine the angular frequency of the drill string dynamic signal data according to the output phase trajectory and the value of the variable-scale coefficient.

[0024] The method of expanding the three-stable chaotic system into an array three-stable chaotic system by adjusting the initial phase angle is to divide the initial phase angle into three intervals and substitute them into the expression of the three-stable chaotic system to obtain the array three-stable chaotic system composed of three different driving equations.

[0025] Exemplarily, the detection of large-frequency signals using a variable-scale three-stable chaotic system includes: A typical three-stable chaotic system is shown in formula (1) (1) In the formula, x is the solution of the three-stable chaotic system, which is a function of time t; k is the damping coefficient, generally taken as 0.5; (-x + x 3 + x 5 ) is the nonlinear restoring force; Asinωt is the driving signal, where A and ω are the amplitude and angular frequency of the driving signal respectively, and ω = 1 rad / s.

[0026] Due to the existence of the nonlinear restoring force term, the state of the solution of the three-stable chaotic system changes regularly with the increase of the amplitude A of the driving signal, successively experiencing homoclinic orbits, bifurcations, chaos, and large-scale periodic states. The variation law of the state of the system solution with the amplitude A is as shown in Figure 2 、 3 . It can be seen that the critical amplitude for the typical three-stable chaotic system to transition from the chaotic state to the large-scale periodic state is 0.588.

[0027] When the solution of the system is in the critical state of the transition from chaos to large-scale periodicity, the system is very sensitive to the amplitude A, and a small change can cause a significant change in the output phase state of the system. Therefore, A is adjusted to the critical value Ac for the transition from chaos to the large-scale periodic state, and the same-frequency signal s(t) to be measured and the noise n(t) are added to formula (1) to obtain the weak signal detection model based on the three-stable chaotic system as shown in formula (2) (2) Placing the three-stable chaotic system in the critical state of the transition from the chaotic state to the large-scale periodic state, and using the signal s(t) + n(t) as the input of the system in this state, the frequency value of the signal s(t) to be measured can be detected through the phase trajectory solved by formula (2). The output phase state of the typical three-stable chaotic system is as shown in Figure 4 、 5 , where the ordinate y represents x'.

[0028] From Figure 4 、 5From the change of [the relevant quantity], it can be seen that since the angular frequencies of the signal to be measured and the driving signal are the same, the input of the signal to be measured can increase the amplitude of the driving signal and exceed the critical value Ac, causing an obvious change in the phase state of the system output. In addition, although the input signal contains noise interference n(t), it does not affect the change of the system output phase state, but only produces roughness at the boundary of the large-scale periodic state, indicating that this method has the immunity characteristic to noise. This is the basic principle of using a typical three-stable chaotic system to detect the frequency of the signal to be measured.

[0029] Now, assume that the expression of the dynamic measurement signal of the drill string is as follows: (3) Keep other parameters in formula (2) unchanged and introduce the variable scale coefficient K , and magnify the dynamic measurement signal on the time axis by K times. At this time, numerically make the angular frequency ω = K ∈ [2π, 6π] rad / s, then the dynamic measurement signal becomes the following form: (4) In the formula, t st represents the time axis after scale transformation.

[0030] It can be seen from formula (4) that the angular frequency of the drill string dynamic measurement signal is magnified by K times on the time axis, that is, the angular frequency ω is compressed from K to 1 rad / s. Under the action of the three-stable chaotic system, it can be detected whether the signal s( t st ) exists, and then the angular frequency value of the signal to be measured can be restored according to the relationship of ω = K .

[0031] However, when dealing with the actual measurement signal, the frequency of the signal to be measured cannot be directly scaled through the linear transformation of formula (4), but the frequency reconstruction of the dynamic measurement signal can be realized by adjusting the step size of numerical calculation. Therefore, the variable scale calculation method is designed as follows: 1) Let the sampling frequency of the dynamic measurement signal be f s , then the step size of numerical calculation is T = 1 / f s ; 2) Substitute the variable scale coefficient, and the numerical calculation step size is updated to T st = K · T =K / f s 。

[0032] After the above processing, the original dynamic measurement signal of the drill string with an angular frequency of ω and a sampling frequency of f s becomes a reconstructed signal with an angular frequency of ω / K and a sampling frequency of f s / K .

[0033] (3) Input the reconstructed signal into the three-stable chaotic system, and apply the updated step size T st to perform iterative calculations on the system, and finally identify the frequency of the dynamic measurement signal according to the change in the output phase state of the system.

[0034] The advantage of this method is that through variable-scale calculation, the angular frequency of the signal to be measured is compressed to 1 rad / s, and the angular frequency of the driving signal remains unchanged during the entire detection process. Therefore, the critical amplitude when the system undergoes a phase change also remains unchanged, thus solving the problem that the change in the driving signal frequency during the detection of the dynamic measurement signal of the drill string will change the size of the critical amplitude Ac when the system undergoes a phase change, which causes difficulties in the application of the frequency detection of the three-stable chaotic system; by changing the numerical calculation step size, the angular frequency of the drill string measurement signal is compressed to meet the detection conditions of the three-stable chaotic system, thus solving the problem that the dynamic response characteristics of the system deteriorate during application, seriously affecting the accuracy and feasibility of frequency detection.

[0035] Full-phase frequency detection using an array of three-stable chaotic systems: To solve the influence of the initial phase angle on frequency detection, this application proposes a full-phase frequency detection scheme based on an array of three-stable chaotic systems. The frequency detection model of the three-stable chaotic system considering the initial phase angle is (5) where η is the amplitude of the signal to be measured; γ and φ are the initial phase angles of the driving signal and the signal to be measured, respectively. Considering the variable-scale processing technology proposed when detecting large-frequency signals using a variable-scale three-stable chaotic system, the angular frequency of the signal to be measured is directly taken as 1 in formula (5).

[0036] By combining and simplifying the first two terms on the right side of formula (5), we can obtain (6) Assume P and Q are the two right sides of a right triangle,R is the hypotenuse and is shown by the following formula (7) Assume again that sin θ = P / R and cos θ = Q / R Then, formula (6) can be further derived as follows (8) From the derivation result of formula (8), it can be seen that the sine function has little influence on the phase trajectory of the solution of the three-stable chaotic system and only affects the initial position of the solution. Therefore, an expression for the amplitude of the above sine function is established as follows (9) The right end of formula (9) is the minimum amplitude that causes the output phase state of the three-stable chaotic system to change. When formula (9) holds, the output phase state of the system changes from chaos to large-scale periodicity. Since the amplitude of the drill string measurement signal is usually greater than 0.1 and not less than 0.02 at least, the amplitude of the signal to be measured η is set to 0.02 and substituted into formula (9) to obtain the following relationship (10) Solving formula (10) gives φ - γ has a variation range of (-60.85°, 60.85°). Therefore, when the initial phase angle γ of the drive signal is 0, the initial phase angle φ of the signal to be measured can only be used to complete frequency detection by means of chaotic phase transition within the range of [-60°, 60°]. In other words, there is a detectable window for the initial phase angle of the signal to be measured, as shown in Figure 6 . The shaded part in the figure represents γ when it is 0 φ the detectable range of

[0037] To fully cover the detection window within the entire range of [-π, π], it can be achieved by adjusting the initial phase angle of the drive signal. Specifically, when the initial phase angle γ of the drive signal is -120°, the detection window of φ is from -180° to -60°; when γ is 120°, the detection window of φ is from 60° to 180°. Therefore, this application extends the typical three-stable chaotic system shown in formula (5) to an array three-stable chaotic system composed of three different drive equations, as shown in formula (11): (11) Substitute the drill string measurement signal into the above-mentioned array three-stable chaotic system. If the output phase state of any one of the equations changes, it can be determined that the signal to be measured exists, and then the frequency value of the signal to be measured can be determined. Therefore, through the implementation of the array three-stable chaotic system, it can effectively solve the problem that the output phase state of the system can change when the signal to be measured is at any initial phase angle during the application of this method, thereby completing the frequency detection of dynamic measurement signals.

[0038] In order to solve the above three problems simultaneously, the technical solution for detecting large-frequency signals using a variable-scale three-stable chaotic system and the technical solution for full-phase frequency detection using an array three-stable chaotic system are combined and used for the optimization of the three-stable chaotic system. The solution process is as Figure 7 shown and summarized as follows: Step 1: Set the initial phase angles of the driving signal to 0 and ±2π / 3 to obtain the array three-stable chaotic system, and input the signal to be measured and noise into the system; Step 2: Set appropriate variable-scale coefficients to reconstruct the angular frequency and sampling frequency of the signal to be measured, and then solve the array three-stable chaotic system with the updated calculation step size; Step 3: Adjust the variable-scale coefficient and observe the output phase trajectory of the array three-stable chaotic system. As long as the output phase state of one equation changes, it means that the value of the variable-scale coefficient at this time is the angular frequency of the signal to be measured.

[0039] In a possible embodiment, the measurement signal of the x-axis accelerometer is used as the experimental object for test analysis. First, construct an array three-stable chaotic system and input the collected data into the array system; then, apply variable-scale coefficients to discretize the input signal, and the sampling frequency is K / fs; finally, continuously adjust the variable-scale coefficient to solve the array system and observe the output phase trajectory as Figure 8 、 9 、10, 11 shown. It can be seen that when the variable-scale coefficient and the angular frequency of the driving signal are both appropriate, the output phase state of the array system jumps to the large-scale periodic state. Thus, it can be known that the technical solution of the present application can effectively identify the frequency value of the drill string dynamic measurement signal.

[0040] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred examples and all changes and modifications falling within the scope of the present invention.

[0041] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A method for detecting the frequency of a drilling tool dynamic measurement signal, characterized in that: include: Collect drilling tool dynamic signal data; Performing high-frequency signal detection of the drilling tool dynamic signal data by using a variable-scale tristable chaotic system; Performing full-phase frequency detection of the drilling tool dynamic signal data by using an array tristable chaotic system; The variable-scale three-stable chaotic system and the array three-stable chaotic system are combined to simultaneously detect the dynamic signal data of the drilling tool.

2. A method for detecting the frequency of a drilling tool dynamic measurement signal according to claim 1, characterized in that: The large-frequency signal detection of the drilling tool dynamic signal data by using the variable-scale tristable chaotic system includes: Reconstructing the drilling tool dynamic signal data to obtain a reconstructed signal; Inputting the reconstructed signal into the variable-scale tristable chaotic system for iterative calculation; The frequency of the reconstructed signal is identified according to the change of the output phase state of the variable-scale tri-stable chaotic system.

3. A method for detecting the frequency of a drilling tool dynamic measurement signal according to claim 2, characterized in that: Reconstructing the drilling tool dynamic signal data to obtain a reconstructed signal includes: Introducing a variable scale coefficient into the drilling tool dynamic signal data to restore the angular frequency value of the drilling tool dynamic signal data to be measured; The frequency reconstruction of the drilling tool dynamic signal data is achieved by adjusting the step size of the numerical calculation.

4. A method for detecting the frequency of a drilling tool dynamic measurement signal according to claim 1, characterized in that: The full-phase frequency detection of the drilling tool dynamic signal data by using the array tri-stable chaotic system includes: The three-stable chaotic system is expanded into an array three-stable chaotic system by adjusting the initial phase angle. Substituting the drilling tool dynamic signal data into the array three-stable chaotic system obtains the full phase frequency of the drilling tool dynamic signal data to be measured.

5. A method for detecting the frequency of a drilling tool dynamic measurement signal according to claim 3, characterized in that: The step of combining the variable-scale tri-stable chaotic system and the array tri-stable chaotic system and simultaneously detecting the dynamic signal data of the drilling tool comprises: An array three-stable chaotic system is obtained by setting the initial phase angle of the drilling tool dynamic signal data; Inputting the drilling tool dynamic signal data and noise to be measured into the array three-stable chaotic system; Reconstructing the angular frequency and sampling frequency of the dynamic signal data by using the variable scaling coefficient; Solving the array tristable chaotic system through the reconstructed calculation step size; The variable scale coefficient is adjusted to complete the detection of the drilling tool dynamic signal data.

6. A method for detecting the frequency of a drilling tool dynamic measurement signal according to claim 5, characterized in that: The step of adjusting the variable scale coefficient to complete the detection of the drilling tool dynamic signal data comprises: Observing the output phase trajectory of the array tristable chaotic system after adjusting the variable scaling coefficient; The angular frequency of the drilling tool dynamic signal data is determined according to the output phase trajectory and the value of the variable scaling coefficient.

7. A method for detecting the frequency of a drilling tool dynamic measurement signal according to claim 4, characterized in that: The method of expanding the three-stable chaotic system into an array three-stable chaotic system by adjusting the initial phase angle is to divide the initial phase angle into three intervals and substitute them into the expression of the three-stable chaotic system to obtain the array three-stable chaotic system composed of three different driving equations.

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