Self-adaptive control method and system for planetary gear stepless speed change drive axle

Abstract

The invention relates to the technical field of gear control, in particular to a planetary gear stepless speed change drive axle self-adaptive control method and system. The method comprises the steps that a vibration impact signal on a planetary gear drive axle shell is collected; performing signal characteristic processing on the vibration impact signal, and determining transient impact characteristics related to tooth surface wear of the planetary gear; evaluating the health trend of the tooth surface of the planetary gear by using the transient impact characteristics to obtain a health trend coefficient; determining a drive axle control scheme based on the health trend coefficient and a trend coefficient threshold value; and controlling the planetary gear stepless speed change drive axle by using the drive axle control scheme so as to complete the self-adaptive control of the drive axle. The invention aims to solve the problems that in the long-term operation process of a planetary gear stepless speed change drive axle in the prior art, accurate control is difficult to carry out through an existing control method, the drive axle cannot provide accurate torque output, and response delay is caused.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gear control, in particular to a planetary gear continuously variable transmission drive axle self-adaptive control method and system. BACKGROUND

[0002] In the power transmission system of modern vehicles, the planetary gear continuously variable transmission drive axle has the ability to continuously adjust the speed ratio. During the long-term operation of the vehicle, the electromagnetic induction or Hall effect sensor used to monitor the speed of the gear ring may experience slight displacement of the fixed support due to slight vibrations during vehicle operation and inevitable dust erosion in the environment. The existing control method can adjust the speed ratio and torque output of the drive axle according to the real-time operating conditions of the vehicle, the intentions of the driver, and environmental changes. As the vehicle continues to operate, the parameter deviation caused by the error data from the slight displacement is continuously accumulated. When the accumulated deviation exceeds a certain threshold, the accuracy of the speed ratio adjustment of the vehicle begins to decline. For example, when the driver needs to accelerate on a city road or suddenly drive onto a steep slope from a flat road, there is a significant lag or overshoot between the hydraulic valve duty cycle output command and the actual required oil pressure.

[0003] In addition, during the long-term use of the vehicle, the original speed signal occasionally experiences weak non-periodic signal jitter or instantaneous loss in a specific speed range. The original data stream of the input speed sensor in the existing drive axle control method receives signals with weak jitter, and the amplitude of the jitter signal does not reach the system-defined fault threshold. Therefore, the speed data with slight errors is transmitted to the subsequent target speed ratio calculation module. Due to the influence of the response speed of the speed ratio adjustment, the drive axle cannot provide accurate torque output in a short period of time, resulting in a temporary lack of driving force or excess driving force of the vehicle. Inaccurate torque output not only affects the smoothness and safety of driving, but also increases the instantaneous impact load of the transmission components, making the control accuracy low and the components prone to damage. SUMMARY

[0004] The present application aims to provide a planetary gear continuously variable transmission drive axle self-adaptive control method and system to solve the problem of inaccurate control of the existing control method of the planetary gear continuously variable transmission drive axle during long-term operation, and the inability of the drive axle to provide accurate torque output, resulting in response lag.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solution: a planetary gear continuously variable transmission drive axle self-adaptive control method, comprising: Collecting vibration impact signals on the planetary gear drive axle housing; The vibration impact signal is processed to determine the transient impact feature related to the wear of the planetary gear tooth surface; The transient impact feature is used to evaluate the health trend of the planetary gear tooth surface to obtain a health trend coefficient; Based on the health trend coefficient and the trend coefficient threshold, a drive axle control scheme is determined; The drive axle control scheme is used to control the planetary gear continuously variable transmission drive axle to complete the adaptive control of the drive axle.

[0006] According to an embodiment of the present application, the step of collecting the vibration impact signal on the planetary gear drive axle housing comprises: The vibration impact original signal on the planetary gear drive axle housing is collected; The vibration impact original signal is processed to remove noise to obtain a denoised vibration impact original signal; The denoised vibration impact original signal is processed by analog-to-digital conversion to obtain a vibration impact digital signal; The vibration impact digital signal is filtered to obtain a vibration impact signal.

[0007] According to an embodiment of the present application, the step of processing the vibration impact signal to determine the transient impact feature related to the wear of the planetary gear tooth surface comprises: The vibration impact signal is extracted to obtain the instantaneous signal amplitude; The instantaneous signal amplitude is compared with the signal amplitude threshold to obtain the instantaneous signal comparison value; Based on the vibration impact signal and the instantaneous signal comparison value, each vibration impact signal is determined; The feature of each vibration impact signal is extracted to determine the transient impact feature related to the wear of the planetary gear tooth surface.

[0008] According to an embodiment of the present application, the step of using the transient impact feature to evaluate the health trend of the planetary gear tooth surface to obtain a health trend coefficient comprises: The impact amplitude, high-frequency energy proportion and feature temperature rise value in the transient impact feature are extracted; Based on the impact amplitude, high-frequency energy proportion and feature temperature rise value, the health trend of the planetary gear tooth surface is evaluated to obtain a health trend coefficient.

[0009] According to an embodiment of the present application, the step of using the impact amplitude, high-frequency energy proportion and feature temperature rise value to evaluate the health trend of the planetary gear tooth surface to obtain a health trend coefficient comprises: The impact amplitude is compared with the preset standard impact amplitude to obtain an impact amplitude ratio; The high-frequency energy proportion is compared with a preset standard high-frequency energy proportion, to obtain an energy ratio value; The feature temperature rise value is compared with a preset standard temperature rise value, to obtain a temperature rise ratio value; Based on the impact amplitude ratio value, the energy ratio value and the temperature rise ratio value, a health trend of the planetary gear tooth surface is evaluated, to obtain a health trend coefficient.

[0010] According to an embodiment of the present application, based on the health trend coefficient and a trend coefficient threshold, the step of determining a drive axle control scheme comprises: A response parameter of the current drive axle is determined in response analysis of the health trend coefficient; The response parameter of the current drive axle is compared with a trend coefficient threshold, to obtain a response deviation value; A preset drive axle control library is used to match the response deviation value with a scheme, to determine a drive axle control scheme.

[0011] According to an embodiment of the present application, the step of matching the response deviation value with a scheme by using a preset drive axle control library to determine a drive axle control scheme comprises: The response deviation value is used to match a transient impact matching feature of the planetary gear set and a sliding friction matching state of the clutch from the preset drive axle control library; Based on the transient impact matching feature of the planetary gear set and the sliding friction matching state of the clutch, a softening adjustment coefficient of the planetary gear set and a softening adjustment coefficient of the clutch are determined; Based on the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch, a drive axle control scheme is determined.

[0012] According to an embodiment of the present application, the step of determining the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch based on the transient impact matching feature of the planetary gear set and the sliding friction matching state of the clutch comprises: The transient impact matching feature of the planetary gear set is subjected to multi-dimensional analysis, to obtain a matching feature analysis result of the planetary gear set; The sliding friction matching state of the clutch is subjected to multi-dimensional analysis, to obtain a matching state analysis result of the clutch; Based on the matching feature analysis result of the planetary gear set, a wear degree of the planetary gear set is determined; Based on the matching state analysis result of the clutch, a wear degree of the clutch is determined; Based on the wear degree of the planetary gear set and the wear degree of the clutch, the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch are determined.

[0013] According to an embodiment of the present application, the step of controlling the planetary gear continuously variable transmission drive axle by the drive axle control scheme after accomplishing the adaptive control of the drive axle further comprises: obtaining a health trend control score after controlling the planetary gear continuously variable transmission drive axle; determining a control index of the planetary gear continuously variable transmission drive axle based on the health trend control score; if the control index is unqualified, issuing an alarm prompt.

[0014] The present application also provides a planetary gear continuously variable transmission drive axle adaptive control system, which comprises: a signal acquisition module for acquiring vibration impact signals on the planetary gear drive axle housing; a feature processing module for processing the vibration impact signals to determine transient impact features related to the planetary gear tooth surface wear; a coefficient evaluation module for evaluating the health trend of the planetary gear tooth surface by using the transient impact features to obtain a health trend coefficient; a scheme determination module for determining a drive axle control scheme based on the health trend coefficient and a trend coefficient threshold value; a drive control module for controlling the planetary gear continuously variable transmission drive axle by the drive axle control scheme to accomplish the adaptive control of the drive axle.

[0015] Compared with the prior art, the planetary gear continuously variable transmission drive axle adaptive control method and system has the following advantages: The application can accurately determine the transient impact characteristics related to the wear of the planetary gear tooth surface by collecting the vibration impact signals on the drive axle housing and processing the signal characteristics. The health trend coefficient can be obtained by using the transient impact characteristics to evaluate the health trend of the planetary gear tooth surface, so as to quantitatively reflect the wear condition of the key components inside the drive axle in real time. Based on the health trend coefficient and the preset trend coefficient threshold, the control scheme of the drive axle can be intelligently determined, and the planetary gear continuously variable transmission drive axle is adaptively controlled by using the scheme. The application can effectively identify and quantify the early wear of the components by introducing real-time monitoring of the vibration impact signals and health trend evaluation. Even when the signal error and control deviation are within the system tolerance range, early warning and intervention can be performed. Through dynamic analysis of the health trend coefficient, the control strategy of the drive axle can be adjusted in time, for example, by softening the adjustment coefficient to optimize the operation of the planetary gear set and the clutch. The drive axle can provide accurate torque output, thereby avoiding the inaccurate speed ratio adjustment and response delay caused by parameter deviation accumulation in the prior art. Not only the running smoothness and driving safety of the drive axle are significantly improved, but also the service life of the planetary gear and other key transmission components is effectively prolonged, and the maintenance cost and failure risk are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the application, the drawings required in the specific embodiments will be briefly introduced below. In all the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0017] Figure 1 The flow chart of the adaptive control method of the planetary gear continuously variable transmission drive axle of the application.

[0018] Figure 2 The structural block diagram of the adaptive control system of the planetary gear continuously variable transmission drive axle of the application.

[0019] In the figure: 210, signal acquisition module; 220, feature processing module; 230, coefficient evaluation module; 240, scheme determination module; 250, drive control module.

[0020] The implementation and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0021] The following drawings disclose several embodiments of the present invention. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details are not intended to limit the invention. That is, in some embodiments of the invention, these practical details are not essential. Furthermore, for the sake of simplicity, some conventional structures and components will be shown in the drawings in a simple schematic manner.

[0022] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0023] Furthermore, in this invention, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms, and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, such a combination should be considered nonexistent and not within the scope of protection claimed by this invention.

[0024] In the power transmission system of a vehicle, the planetary gear continuously variable transmission drive axle has the ability to continuously adjust the speed ratio. However, during the long-term use of the vehicle, the rotating speed sensor probe inside the drive axle may have a slight displacement of the fixed support due to the slight vibration generated during the vehicle driving process and the inevitable dust erosion in the environment. The displacement may cause a slight change in the air gap between the sensor and the measured target, which in turn may cause the output of the original rotating speed signal to occasionally have weak non-periodic signal jitter or instantaneous loss in a certain speed range. The signal with weak jitter is transmitted to the existing control method of the drive axle as the original data stream of the input rotating speed sensor; the existing method cannot completely filter out the noise caused by weak jitter, resulting in the transmission of rotating speed data with slight errors to the subsequent target speed ratio calculation module. In the working conditions of frequent start-stop or low-speed heavy-load climbing of the vehicle, the rotating speed data with errors will cause a slight deviation between the expected speed ratio output by the target speed ratio calculation module and the actual optimal speed ratio. With the continuous operation of the vehicle, the adaptive parameter deviation caused by the error data will be continuously accumulated. When the accumulated deviation exceeds a certain critical value, the accuracy of the speed ratio adjustment of the control system begins to decline. In the working conditions that require rapid and large adjustments of the speed ratio, such as deep pressing the accelerator when emergency overtaking on urban roads or suddenly driving into steep slopes from flat roads, the wrong adaptive parameters will cause a significant lag or overshoot between the hydraulic valve duty cycle output command and the actual required oil pressure. The drive axle cannot provide accurate torque output in a short time, resulting in a temporary lack or excess of driving force of the vehicle at critical moments. Inaccurate torque output not only affects the smoothness and safety of driving, but also increases the instantaneous impact load of the transmission components.

[0025] In order to further understand the content, characteristics and effects of the present application, the following examples are given, and are described in detail as follows with reference to the accompanying drawings: Please refer to Figure 1 The present application provides a planetary gear continuously variable transmission drive axle adaptive control method, comprising the following steps: S100, collect vibration impact signals on the planetary gear drive axle housing. Among them, the planetary gear continuously variable transmission drive axle refers to a drive axle system that combines planetary gear mechanism and continuously variable transmission principle. Its core is to realize continuous and stepless change of transmission ratio to adapt to different driving conditions, thereby improving fuel economy and driving smoothness of the vehicle. The vibration impact signal refers to the vibration waveform with specific frequency and amplitude generated by the mechanical action of friction, engagement and impact between components during the operation of the drive axle. These signals carry key information about the health status of the internal components of the drive axle, especially the planetary gear tooth surface. This step can achieve the collection of vibration impact signals in various ways. For example, piezoelectric acceleration sensors can be installed at key positions of the planetary gear drive axle housing. The sensor can convert the mechanical vibration received by the housing into an electrical signal output. The sensor usually has wide frequency response and high sensitivity, which can effectively capture weak impact vibrations caused by tooth surface wear. Another way is to use a magneto-electric speed sensor, which measures vibration speed by sensing magnetic field changes, suitable for collecting low-frequency vibration signals. In addition, optical fiber sensors can also be considered, which use the strain effect of optical fibers to sense vibrations, with strong anti-electromagnetic interference ability and small size. The original signal collected by the sensor is usually an analog signal, which needs to be processed later to be used for analysis.

[0026] S200, signal feature processing of the vibration impact signals to determine the transient impact features related to the planetary gear tooth surface wear. Among them, the transient impact feature refers to the short-time high-energy signal component that can reflect the initial features of tooth surface wear, spalling and fracture, such as impact amplitude, impact frequency and energy distribution, etc. extracted from the vibration impact signal. Specifically, after receiving the vibration impact signal, a series of processing is needed to extract useful features. First, the collected signal is analyzed in time domain, such as calculating the root mean square value, peak value and kurtosis of the signal, etc. The parameters can preliminarily reflect the energy and impact characteristics of the signal. Then, frequency domain analysis can be performed, such as converting the time domain signal to frequency domain by fast Fourier transform (FFT), observing the frequency spectrum distribution of the signal, and identifying the energy peak value related to the gear meshing frequency and fault characteristic frequency. In addition, time-frequency analysis methods such as wavelet transform can also be used to decompose the signal at multiple scales, so as to capture transient impact features at different frequencies and time scales. For example, when there is a small spalling on the tooth surface, transient impact energy will be generated at high frequencies, which can be effectively identified by wavelet transform.

[0027] S300, evaluate the health trend of the planetary gear tooth surface by using the transient impact features, and obtain a health trend coefficient. The health trend coefficient is a quantitative index for comprehensively evaluating the wear degree and development trend of the planetary gear tooth surface, and the numerical change can directly reflect the deterioration or improvement of the tooth surface health condition. After the transient impact features are extracted, they need to be converted into quantifiable health trend coefficients. The extracted impact amplitude, high-frequency energy proportion, and feature temperature rise value can be used as inputs to construct a multivariate evaluation model. The model can use fuzzy logic reasoning system to map these feature values to different fuzzy sets, such as slight wear, moderate wear, and severe wear, and make a comprehensive judgment through fuzzy rules, and finally output a health trend coefficient between 0 and 1, where 1 represents complete health and 0 represents severe wear. At the same time, machine learning algorithms such as support vector machine (SVM) or neural network can be used to train a large amount of historical data, learn the complex nonlinear relationship between transient impact features and tooth surface health condition, and predict and evaluate the health trend of the current tooth surface.

[0028] S400, determine the drive axle control scheme based on the health trend coefficient and the trend coefficient threshold. The trend coefficient threshold is a critical value preset to judge whether the tooth surface health condition reaches the level that needs intervention. When the health trend coefficient exceeds the threshold, it indicates that the drive axle may have potential failure or performance decline risk. The drive axle control scheme refers to a series of control strategies determined according to the health trend coefficient and the trend coefficient threshold, which are used to adjust the drive axle operating parameters (such as speed ratio, torque distribution, and clutch engagement pressure, etc.), aiming to slow down wear, improve performance, or avoid failure through optimized control. Specifically, after obtaining the health trend coefficient, it needs to be compared with the preset trend coefficient threshold to decide whether to adjust the control strategy of the drive axle. Multiple trend coefficient thresholds can also be preset, each corresponding to a different control level. For example, when the health trend coefficient is higher than the first threshold, it indicates that the tooth surface condition is good, and the drive axle maintains normal control scheme; when the health trend coefficient is between the first and second thresholds, it indicates that the tooth surface has slight wear, and a flexible control scheme can be started, such as slightly reducing the shift impact or adjusting the speed ratio switching strategy; when the health trend coefficient is lower than the second threshold, it indicates that the tooth surface wear is more serious, and a protective control scheme needs to be started, such as limiting the maximum torque output or suggesting maintenance. These control schemes can be pre-stored in a drive axle control library for matching and selection according to the health trend coefficient.

[0029] S500, using the drive axle control scheme to control the planetary gear continuously variable transmission drive axle to complete the adaptive control of the drive axle. After the drive axle control scheme is determined, it needs to be applied to the actual drive axle control system. The determined control scheme parameters (such as the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch) can be sent to the electronic control unit (ECU) of the drive axle through the controller area network (CAN) bus. After the ECU receives these parameters, the actuator instructions such as the duty cycle of the hydraulic valve and the motor current are adjusted according to the new control scheme, so as to change the operating parameters such as the speed ratio, torque output and clutch engagement state of the drive axle. For example, if the control scheme indicates that the shift shock needs to be reduced, the ECU will adjust the engagement pressure curve of the clutch to make it more smooth during the shift process. In this way, the operating state of the drive axle can be adaptively adjusted according to the health trend of the tooth surface, thereby prolonging the service life of the components and maintaining the best performance.

[0030] The planetary gear continuously variable transmission drive axle adaptive control method provided by the present application realizes the dynamic adaptive adjustment of the drive axle control strategy by introducing real-time evaluation of the health trend of the planetary gear tooth surface. By collecting the vibration impact signals on the drive axle housing and performing fine signal feature processing, the present application can accurately determine the transient impact features related to the wear of the planetary gear tooth surface. Transient impact features are sensitive indicators of early tooth surface wear and can detect potential problems earlier than traditional fault diagnosis methods. Further, the present application uses transient impact features to quantitatively evaluate the health trend of the planetary gear tooth surface to obtain a health trend coefficient. The health trend coefficient intuitively reflects the degree of wear and development trend of the tooth surface, providing a reliable basis for subsequent control decisions. Further, it can effectively identify and quantify the early wear of the components, even when the signal error and control deviation are within the system tolerance range, it can also provide early warning and intervention. Through dynamic analysis of the health trend coefficient, the control strategy of the drive axle can be adjusted in time, for example, by using the softening adjustment coefficient to optimize the operation of the planetary gear set and the clutch. The drive axle can provide accurate torque output, thereby avoiding the inaccuracy of speed ratio adjustment and response delay caused by parameter deviation accumulation in existing methods. Not only significantly improves the running smoothness and driving safety of the drive axle, but also effectively prolongs the service life of the planetary gear and other key transmission components, reduces maintenance costs and fault risks.

[0031] In some embodiments of the present application described above, the step of collecting vibration impact signals on the planetary gear drive axle housing comprises: Collecting the vibration impact original signal on the planetary gear drive axle housing. Among them, this step refers to obtaining the original vibration data generated by the drive axle during operation through the sensor (such as an acceleration sensor or a piezoelectric sensor) installed on the drive axle housing. The original signal is usually an analog signal, which contains a wealth of information about the running state of the internal mechanical components of the drive axle, especially the planetary gear.

[0032] The vibration impact original signal is subjected to noise removal processing to obtain a denoised vibration impact original signal. This step aims to eliminate the clutter caused by environmental interference, sensor noise or unrelated mechanical vibration in the original signal. For example, wavelet denoising, empirical mode decomposition (EMD) or adaptive filtering can be used to improve the signal-to-noise ratio and ensure the accuracy of subsequent analysis.

[0033] The denoised vibration impact original signal is subjected to analog-to-digital conversion processing to obtain a vibration impact digital signal. Specifically, since modern signal processing is usually carried out in the digital domain, it is necessary to convert continuous analog signals into discrete digital signals. Usually, an analog-to-digital converter (ADC) is used to convert analog voltage or current signals into a series of digital samples for computer storage and processing.

[0034] The vibration impact digital signal is subjected to filtering processing to obtain a vibration impact signal. The filtering processing in this step aims to extract specific frequency components related to planetary gear tooth surface wear from the digital signal while suppressing other irrelevant frequencies. For example, a band-pass filter can be used to isolate the planetary gear meshing frequency and its harmonics, or a low-pass or high-pass filter can be used to remove interference in a specific frequency band, resulting in a purer and more representative vibration impact signal.

[0035] This embodiment refines the original vibration impact signal collection process into a series of ordered sub-steps to ensure the quality and effectiveness of the vibration impact signal obtained. First, directly collecting the original signal is the basis for obtaining the running state of the drive axle. Second, noise removal processing can effectively improve the purity of the signal and avoid interference with subsequent feature extraction and health assessment caused by noise. Next, analog-to-digital conversion processing enables analog signals to be processed and analyzed by digital systems, making it possible to apply complex algorithms. Finally, filtering processing further refines the signal, making it more focused on key information related to planetary gear tooth surface wear, thereby providing high-quality input for subsequent transient impact feature determination.

[0036] In some embodiments of the application described above, the vibration impact signal is subjected to signal feature processing to determine the transient impact features related to the planetary gear tooth surface wear. extracting the vibration impact signal to obtain a transient signal amplitude. This step refers to obtaining the instantaneous intensity or energy size of the vibration impact signal at different time points. Among them, the transient signal amplitude can be understood as the instantaneous amplitude or instantaneous energy value of the signal, and the purpose is to capture the instantaneous energy change in the signal that may be caused by gear surface wear.

[0037] comparing the transient signal amplitude with a signal amplitude threshold value to obtain a transient signal comparison value. Among them, the signal amplitude threshold value is a reference value for distinguishing normal vibration from abnormal impact, which can be determined according to empirical data, theoretical model or actual test results. Through comparison, the transient impact event exceeding the normal range in the signal can be identified, so as to obtain the transient signal comparison value, and the purpose is to preliminarily screen out the potential impact signal related to wear.

[0038] Based on the vibration impact signal and the transient signal comparison value, each vibration impact signal is determined. Specifically, when the transient signal comparison value indicates that there is an abnormal impact, the original vibration impact signal can be segmented in the time period of the impact, so as to obtain a plurality of independent vibration impact signals, each signal corresponding to one or more impact events, and the purpose is to decompose the complex continuous signal into discrete impact events for easy analysis.

[0039] Each vibration impact signal is extracted to determine the transient impact feature related to the planetary gear tooth surface wear. Among them, the feature extraction can include but is not limited to time domain, frequency domain or time-frequency domain analysis of the signal segment to obtain impact amplitude, impact duration, impact energy or high frequency component ratio and other characteristic parameters. It can directly or indirectly reflect the wear state of the planetary gear tooth surface, and the purpose is to quantify the key information directly related to the tooth surface wear from the segmented signal segment.

[0040] The embodiment can effectively identify and extract the transient impact feature directly related to the planetary gear tooth surface wear from the complex vibration signal by fine processing of the vibration impact signal. First, by extracting the transient signal amplitude and comparing it with the preset signal amplitude threshold value, the potential impact event can be preliminarily screened out, avoiding the analysis of a large number of irrelevant signals. Secondly, based on the comparison result, the vibration impact signal is segmented, so that each impact event can be analyzed independently, improving the pertinence of the analysis. Finally, the characteristics of the impact are quantified by extracting the characteristics of each impact signal, so as to accurately determine the transient impact feature related to the planetary gear tooth surface wear. Further, the accuracy and reliability of the extracted feature are ensured, which provides a solid foundation for subsequent health trend evaluation.

[0041] In some embodiments of the above-mentioned embodiments of the present application, the step of evaluating the health trend of the planetary gear tooth surface by using the transient impact feature to obtain a health trend coefficient comprises: The impact amplitude, high-frequency energy proportion, and feature temperature rise value in the transient impact feature are extracted. Specifically, the impact amplitude refers to the instantaneous peak intensity of the vibration signal caused by tooth surface wear or damage in the transient impact feature, which directly reflects the severity of the impact. The high-frequency energy proportion refers to the proportion of high-frequency components in the frequency spectrum analysis of the transient impact feature, and tooth surface wear usually leads to an increase in high-frequency vibration energy. The feature temperature rise value refers to the local temperature rise caused by the aggravation of tooth surface friction and wear during the operation of the planetary gear drive axle, which is a direct thermal manifestation of the wear degree. The extraction of the feature aims to quantify the wear state of the planetary gear tooth surface from multiple dimensions.

[0042] The health trend of the planetary gear tooth surface is evaluated based on the impact amplitude, high-frequency energy proportion, and feature temperature rise value to obtain a health trend coefficient.

[0043] Specifically, when the planetary gear drive axle is running, the signal acquisition module continuously acquires vibration impact signals. After determining the transient impact feature, the coefficient evaluation module further analyzes the transient impact feature. Specifically, by performing time domain analysis on the transient impact feature, the impact amplitude can be extracted, such as by peak detection or root mean square value calculation. By performing frequency domain analysis on the transient impact feature, such as using Fast Fourier Transform (FFT), the energy distribution of different frequency bands can be calculated to obtain the high-frequency energy proportion. At the same time, through the temperature sensor installed at the key position of the drive axle, the feature temperature rise value can be monitored and calculated in real time. Subsequently, the extracted impact amplitude, high-frequency energy proportion, and feature temperature rise value are input into a pre-set evaluation model (such as an evaluation model based on machine learning or expert experience), which comprehensively considers the change trend and mutual relationship of these indicators, and finally outputs a quantitative health trend coefficient, which can directly reflect the current wear state of the planetary gear tooth surface and its development trend.

[0044] By extracting the impact amplitude, high-frequency energy proportion, and feature temperature rise value, this embodiment can more comprehensively and accurately capture the wear information of the planetary gear tooth surface. The impact amplitude directly reflects the instantaneous intensity of tooth surface damage, the high-frequency energy proportion reveals the change in vibration mode caused by wear, and the feature temperature rise value provides thermodynamic evidence in the wear process. By comprehensively analyzing these multi-dimensional features, the one-sidedness or inaccuracy that may be caused by single indicator evaluation can be avoided, making the evaluation of the health trend of the planetary gear tooth surface more scientific and reliable, and effectively making up for the possible shortcomings of the evaluation indicators in the basic scheme.

[0045] In some embodiments of the application described above, based on the impact amplitude, high-frequency energy proportion and characteristic temperature rise value, the health trend of the planetary gear tooth surface is evaluated to obtain a health trend coefficient, and the step comprises: The impact amplitude is compared with a preset standard impact amplitude to obtain an impact amplitude ratio. The preset standard impact amplitude refers to a reference value of the impact amplitude obtained through a large number of experiments or theoretical calculations when the planetary gear continuously variable transmission drive axle is in a healthy state or a new factory state, and the purpose is to provide a reliable reference point for subsequent wear evaluation. The impact amplitude ratio reflects the deviation of the current impact amplitude from the healthy state.

[0046] The high-frequency energy proportion is compared with a preset standard high-frequency energy proportion to obtain an energy ratio. The preset standard high-frequency energy proportion refers to a reference value of the proportion of high-frequency energy in the vibration signal when the drive axle is in normal operation and the tooth surface has no obvious wear, and the purpose is to quantify the change of high-frequency vibration energy because tooth surface wear usually leads to an increase in high-frequency vibration energy. The energy ratio indicates the change of the current high-frequency energy proportion from the healthy state.

[0047] The characteristic temperature rise value is compared with a preset standard temperature rise value to obtain a temperature rise ratio. The preset standard temperature rise value refers to a reference value of the temperature rise when the drive axle is in a normal working temperature range and the tooth surface has no abnormal friction or wear, and the purpose is to assist in judging the wear degree through temperature change because wear produces additional friction heat. The temperature rise ratio reflects the deviation of the current characteristic temperature rise value from the healthy state.

[0048] Based on the impact amplitude ratio, the energy ratio and the temperature rise ratio, the health trend of the planetary gear tooth surface is evaluated to obtain a health trend coefficient. The health trend coefficient of this step can be obtained by weighted average, fuzzy logic reasoning or machine learning model, etc. The purpose is to provide a comprehensive quantitative index to represent the wear degree and health condition of the planetary gear tooth surface.

[0049] In this embodiment, the preset standard values are introduced, and the current impact amplitude, high-frequency energy proportion and characteristic temperature rise value are compared with these standard values to obtain the impact amplitude ratio, energy ratio and temperature rise ratio. The evaluation method based on the ratio can effectively eliminate the influence of different working conditions or different drive axle individual differences, and convert the original absolute feature value into a relative standardized index. Due to the standardization, the evaluation of the health trend of the planetary gear tooth surface is more objective and accurate, and the real degree of tooth surface wear can be more accurately reflected, avoiding the evaluation deviation caused by directly using the original feature value.

[0050] In some embodiments of the present application, based on the health trend coefficient and the trend coefficient threshold, the step of determining the drive axle control scheme comprises: In response to the health trend coefficient, a response parameter of the current drive axle is determined. Specifically, the response analysis of the health trend coefficient refers to in-depth analysis of the law, rate of change and fluctuation of the health trend coefficient over time to capture the dynamic characteristics of the current operating state of the drive axle. The response parameter can be understood as an index reflecting the sensitivity and response speed of the drive axle to the change in the health trend, for example, it can be the rate of change, acceleration or average value of the health trend coefficient in a certain time window, etc. The purpose is to extract dynamic and more instructive operating state information from the static health trend coefficient.

[0051] The response parameter of the current drive axle is compared with the trend coefficient threshold to obtain a response deviation value. This step refers to comparing the drive axle response parameter obtained by response analysis with the pre-set trend coefficient threshold. The trend coefficient threshold can be set according to the design standard, operation experience or historical data of the drive axle, and is used to define different levels of drive axle health status or critical points requiring control measures. The response deviation value quantifies the gap between the dynamic response of the current drive axle and the expected or safe threshold, providing a quantitative basis for matching the subsequent control scheme.

[0052] A pre-set drive axle control library is used to match the response deviation value to determine the drive axle control scheme. This step refers to selecting the most suitable control strategy in the pre-established drive axle control library according to the calculated response deviation value. The pre-set drive axle control library can contain various control schemes for different response deviation value ranges or types, such as adjusting the lubrication strategy of the planetary gear set, the engagement or disengagement timing of the clutch and the adjustment amplitude of the gear ratio, etc. Through scheme matching, the determined drive axle control scheme can accurately respond to the dynamic response characteristics and health status of the current drive axle, achieving fine and adaptive control.

[0053] Specifically, in a certain operation, the health trend coefficient of the planetary gear drive axle shows a continuous downward trend, and the rate of its decline (i.e., the response parameter) exceeds the preset trend coefficient threshold. First, the health trend coefficient is subjected to response analysis to determine its average rate of decline over a period of time. Then, the rate of decline is compared with the preset rate of decline threshold to obtain a response deviation value. Based on the response deviation value, a corresponding control scheme is matched from the preset drive axle control library. For example, if the deviation value corresponds to a mild wear acceleration scenario, the control library can match a control scheme that increases the lubricating oil flow and reduces the maximum torque output. This scheme is then used to control the planetary gear continuously variable transmission drive axle to slow down the wear process and maintain stable operation of the drive axle. In this way, the control scheme of the drive axle can be finely adjusted in real time according to its dynamic health trend, rather than only triggering a single alarm or shutdown operation when the health coefficient falls below a certain fixed threshold.

[0054] The present embodiment can extract the dynamic response parameter of the drive axle from the static health trend coefficient by introducing response analysis of the health trend coefficient, thereby more comprehensively reflecting the real-time operating state and potential wear trend of the drive axle. Since the response parameter is compared with the trend coefficient threshold to obtain a quantitative response deviation value, the control requirements of the drive axle are accurately identified and quantified. On this basis, by using the preset drive axle control library to match a scheme, the most suitable control strategy can be selected according to the specific response deviation value, avoiding the shortcomings that may be caused by a single or rough control scheme. The control scheme of the drive axle is no longer a simple threshold trigger, but a fine adaptive adjustment based on dynamic response and quantitative deviation, thereby effectively avoiding the possible lack of fineness or adaptability of the control scheme in the basic scheme.

[0055] In some embodiments of the above-mentioned embodiments of the present application, the step of matching a scheme for the response deviation value using the preset drive axle control library to determine the drive axle control scheme comprises: The response deviation value is used to match the transient impact matching characteristics of the planetary gear set and the sliding friction matching state of the clutch from a preset drive axle control library. The response deviation value refers to the difference between the response parameter of the current drive axle and the trend coefficient threshold. The response deviation value is used for matching from the preset drive axle control library. The preset drive axle control library can be a database containing a plurality of predefined control strategies and corresponding system state parameters. By the response deviation value, the transient impact matching characteristics of the planetary gear set and the sliding friction matching state of the clutch closest to the current drive axle state can be retrieved and matched from the control library. The transient impact matching characteristics can be understood as the impact characteristics that the planetary gear set can exhibit under a certain response deviation value, such as impact frequency and amplitude. The sliding friction matching state of the clutch refers to the sliding friction characteristics that the clutch can exhibit under the same response deviation value, such as sliding friction time and sliding friction torque. The matching characteristics and state are obtained in advance by experiment, simulation or historical data analysis and stored in the control library.

[0056] Based on the transient impact matching characteristics of the planetary gear set and the sliding friction matching state of the clutch, the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch are determined. The softening adjustment coefficient is a key parameter for adjusting the control strategy of the planetary gear continuously variable drive axle, and its purpose is to fine-tune the control parameters of specific components (such as the planetary gear set and the clutch) to adapt to their current working state or wear degree without affecting the overall performance of the drive axle. For example, when the matching characteristics show that the planetary gear set has slight wear, the corresponding softening adjustment coefficient can be determined to reduce its impact load under certain working conditions. Similarly, when the clutch has a certain sliding friction trend, a softening adjustment coefficient of the clutch can be determined to optimize its engagement or disengagement process. The determination of the coefficient can be based on a preset lookup table, fuzzy logic rules or a machine learning model.

[0057] Based on the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch, the drive axle control scheme is determined. The control scheme in this step is a comprehensive instruction set for guiding the drive control module to actually control the planetary gear continuously variable drive axle. Specifically, the scheme can include fine-tuning the transmission ratio adjustment strategy of the planetary gear set, the engagement or disengagement timing of the clutch, the oil pressure control parameters, etc. to achieve adaptive control of the drive axle.

[0058] By matching the response deviation value with the detailed features in the preset drive axle control library, the embodiment can more finely identify the potential working state or wear trend of the key components (such as the planetary gear set and the clutch) inside the drive axle. Due to this detailed matching, the subsequent determination of the softening adjustment coefficients of the planetary gear set and the clutch can be targeted. The softening adjustment coefficients directly reflect the need for flexible control of specific components, thereby avoiding a one-size-fits-all control method. The finally determined drive axle control scheme can better adapt to the actual operating conditions of the drive axle, achieving more accurate adaptive control.

[0059] In some embodiments of the present application, based on the transient impact matching feature of the planetary gear set and the sliding friction matching state of the clutch, the step of determining the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch comprises: The transient impact matching feature of the planetary gear set is analyzed in multiple dimensions to obtain a matching feature analysis result of the planetary gear set. This step refers to in-depth and comprehensive data processing and pattern recognition of the transient impact matching feature of the planetary gear set matched from the preset drive axle control library. The analysis can include but is not limited to time domain analysis, frequency domain analysis, time-frequency joint analysis, and statistical feature analysis, etc. For example, in the time domain, statistical quantities such as peak value, root mean square value, kurtosis, and skewness of the impact signal can be analyzed; in the frequency domain, Fourier transform can be performed to analyze the energy proportion or harmonic characteristics of specific frequency components; in the time-frequency joint domain, wavelet analysis or Hilbert-Huang transform can be used to capture local features of transient impact. The purpose is to reveal the actual operating state and potential wear signs of the planetary gear set from multiple angles. Further, the matching feature analysis result of the planetary gear set can be obtained, which is a comprehensive data set formed after multi-dimensional analysis and can more comprehensively reflect the health status of the planetary gear set.

[0060] The sliding friction matching state of the clutch is analyzed in multiple dimensions to obtain a matching state analysis result of the clutch. This step refers to detailed evaluation of the sliding friction matching state of the clutch matched from the preset drive axle control library. The analysis can involve multi-aspect analysis of signals such as vibration, temperature, and torque fluctuation generated during sliding friction. For example, parameters such as energy dissipation, friction coefficient change, and sliding friction duration during sliding friction can be analyzed. The purpose is to accurately judge the friction characteristics and wear trend of the clutch during operation. Thus, the matching state analysis result of the clutch can be obtained, which is a comprehensive index used to represent the current working state and wear condition of the clutch after multi-dimensional analysis.

[0061] Based on the matching feature analysis result of the planetary gear set, the wear degree of the planetary gear set is determined. This step can be understood as quantifying the actual wear state of the planetary gear set by comparing the analysis result with a preset wear model or threshold. For example, when the kurtosis value or high-frequency energy proportion of the transient impact signal exceeds a certain threshold, it can be determined that the planetary gear set has mild wear; when these indicators further deteriorate, it can be determined as moderate or severe wear. In practical applications, a wear grade evaluation table can be established or a machine learning algorithm can be used to map the matching feature analysis result to a specific wear grade, such as no wear, slight wear, moderate wear, and severe wear.

[0062] Based on the matching state analysis result of the clutch, the wear degree of the clutch is determined. This step refers to evaluating the actual wear condition of the clutch friction plate according to the analysis result of the clutch slip state. For example, if the temperature abnormally rises or the friction coefficient significantly decreases during the slip process, it may indicate that the clutch friction plate is worn. Specifically, the wear grade of the clutch can be determined according to the slip energy dissipation, friction plate thickness change (indirectly measured or model calculated), and other indicators, combined with a preset wear threshold or empirical curve.

[0063] Based on the wear degree of the planetary gear set and the wear degree of the clutch, the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch are determined. After the actual wear state of each component is determined, this step can more accurately adjust its control parameters. For example, the higher the wear degree, the greater the softening adjustment coefficient may be needed to reduce the impact and prolong the service life of the component. The determination process can be based on a preset control strategy table, a fuzzy logic controller, or an adaptive algorithm, taking the wear degree as input and outputting the corresponding softening adjustment coefficient.

[0064] Specifically, during the operation of the drive axle, the transient impact matching characteristics of the planetary gear set and the sliding friction matching state of the clutch are collected. First, for the transient impact matching characteristics of the planetary gear set, fast Fourier transform (FFT) can be performed to obtain frequency domain information, and kurtosis value and root mean square (RMS) value can be calculated. For example, if the FFT analysis shows that the proportion of high-frequency energy at the meshing frequency of the planetary gear and its harmonics increases significantly, and the kurtosis value exceeds the first preset threshold, it indicates that the planetary gear tooth surface may have initial wear. Further, by comparing these frequency domain and time domain characteristics with the preset wear model, the wear degree of the planetary gear set can be determined as slight wear. Second, for the sliding friction matching state of the clutch, the temperature change rate and the torque fluctuation amplitude during the shifting process can be analyzed. For example, if the highest temperature during the sliding friction process exceeds the second preset threshold, and the torque fluctuation amplitude is greater than the third preset threshold, it indicates that the clutch friction plate may have wear. By comprehensively evaluating these parameters, the wear degree of the clutch can be determined as moderate wear. Finally, based on the determined slight wear of the planetary gear set and the moderate wear of the clutch, the preset softening adjustment coefficient lookup table can be consulted. For example, for the planetary gear set with slight wear, the softening adjustment coefficient can be determined as 0.15; for the clutch with moderate wear, the softening adjustment coefficient can be determined as 0.25. The adjustment coefficient is then applied to the control strategy of the drive axle to achieve adaptive control of the planetary gear continuously variable drive axle, thereby effectively reducing component wear and prolonging the overall life of the drive axle while ensuring performance.

[0065] The present embodiment can more comprehensively and deeply understand the actual operating conditions and health trends of the key components inside the drive axle by performing multi-dimensional analysis on the transient impact matching characteristics of the planetary gear set and the sliding friction matching state of the clutch. Existing solutions may only rely on direct mapping of matching characteristics without fully considering the component wear information implied behind the characteristics. Due to the introduction of multi-dimensional analysis, more relevant deep features related to wear can be extracted from complex signals, resulting in more accurate matching characteristic analysis results and matching state analysis results. On this basis, by comparing the analysis results with the preset wear model or empirical data, the wear degree of the planetary gear set and the clutch can be accurately quantified. This accurate assessment of wear degree provides a solid foundation for the determination of the softening adjustment coefficient. By taking the wear degree as a key input, the softening adjustment coefficient of the planetary gear set and the clutch can be dynamically adjusted according to the actual health status of the components, thereby achieving more refined and adaptive control of the drive axle.

[0066] In some embodiments of the above-mentioned drive axle control scheme, after the step of controlling the planetary gear continuously variable drive axle to complete the adaptive control of the drive axle, the method further comprises: A health trend control score after the control of the planetary gear continuously variable transmission drive axle is obtained. This step refers to monitoring and evaluating the running state of the drive axle again after the drive axle is adjusted by adaptive control, so as to obtain a quantitative score reflecting the current health condition. The score can be obtained based on the same evaluation method as the initial health trend coefficient, for example, the transient impact features are extracted again by collecting the vibration impact signals, and then the gear face health trend is evaluated, or the health state of the drive axle is comprehensively evaluated by other parameters. The purpose is to verify whether the control scheme applied is effective in improving the health condition of the drive axle.

[0067] Based on the health trend control score, a control index of the planetary gear continuously variable transmission drive axle is determined. This step refers to comparing and analyzing the obtained health trend control score with the preset performance standard or health threshold. The control index can be a binary judgment (qualified or unqualified), or a multi-level evaluation result for quantifying the actual effect of the control scheme. For example, a qualified range of the health trend control score can be set, and if the score falls within the range, the control effect is considered to be good, otherwise, the control effect is considered to be poor or there is a new problem.

[0068] If the control index is unqualified, an alarm prompt is issued. Specifically, when the control index determined by the above evaluation shows that the health state of the drive axle fails to meet the expected standard, the system will automatically trigger an alarm mechanism. The alarm prompt can be realized in various forms, such as through sound and light signals, display screen information or remote notification (such as SMS or email), etc., to timely remind the operator or maintenance personnel to pay attention to the abnormal condition of the drive axle, so as to take further inspection, diagnosis or maintenance measures.

[0069] Specifically, during the operation of the planetary gear continuously variable transmission drive axle, the health trend coefficient is found to be low due to gear face wear, and then the corresponding drive axle control scheme is determined and executed according to the preset drive axle control library, for example, the slip state of the clutch is adjusted to reduce the impact. After completing this control operation, the monitoring is not stopped immediately, but the vibration impact signals on the drive axle housing are continuously collected, and the signal feature processing and health trend evaluation are performed again, so as to obtain a health trend control score. For example, if the health trend control score is still lower than the preset qualified threshold, it indicates that the current control scheme has not completely solved the gear face wear problem, or there is a new abnormality. At this time, the control index is determined to be unqualified, and an alarm prompt is issued, for example, the drive axle health abnormality is displayed on the display screen in the cab, and the warning information of please check is displayed, and at the same time, the sound and light alarm can be triggered, or even some running parameters of the drive axle are limited to prevent further damage. Further, even if the adaptive control does not completely take effect, the abnormality can be timely discovered and warned, ensuring the safe operation of the drive axle.

[0070] The embodiment can judge the effectiveness of adaptive control in real time by increasing the evaluation of the health state after control and comparing it with preset indexes. When the control effect is not ideal, an alarm prompt is sent in time, so that the drive axle continues to run in the case of potential failure or incomplete problem solving is avoided, and the verification of control effect and risk early warning are realized.

[0071] Based on the adaptive control method of the planetary gear continuously variable drive axle in any one of the above embodiments, please refer to Figure 2 The application further provides a planetary gear continuously variable drive axle adaptive control system, which comprises a signal acquisition module 210, a feature processing module 220, a coefficient evaluation module 230, a scheme determination module 240 and a drive control module 250.

[0072] The signal acquisition module 210 is used for acquiring the vibration impact signal on the planetary gear drive axle shell.

[0073] The feature processing module 220 is used for signal feature processing of the vibration impact signal to determine the transient impact feature related to the planetary gear tooth surface wear.

[0074] The coefficient evaluation module 230 is used for evaluating the health trend of the planetary gear tooth surface by using the transient impact feature to obtain a health trend coefficient.

[0075] The scheme determination module 240 is used for determining the drive axle control scheme based on the health trend coefficient and the trend coefficient threshold.

[0076] The drive control module 250 controls the planetary gear continuously variable drive axle by using the drive axle control scheme to complete the adaptive control of the drive axle.

[0077] In this embodiment, the vibration impact signal of the drive axle housing is acquired in real time by the signal acquisition module 210, and the signal is analyzed in depth by the feature processing module 220 to identify the transient impact features related to the wear of the planetary gear tooth surface. Subsequently, the coefficient evaluation module 230 quantifies the health trend of the tooth surface according to these features and generates a health trend coefficient. The scheme determination module 240 intelligently generates an adaptive drive axle control scheme based on the coefficient and a preset threshold. Finally, the drive control module 250 applies this scheme to the actual operation control of the drive axle, thereby realizing dynamic optimization of the performance of the drive axle and effective extension of the service life of the components, and solving the problem that the traditional method is difficult to detect the performance degradation and component damage caused by the accumulation of small errors. That is, through the close cooperation of the signal acquisition module 210, the feature processing module 220 and the coefficient evaluation module 230, real-time and refined evaluation of the health trend of the planetary gear tooth surface is realized. This forward-looking evaluation capability enables the system to generate and implement the corresponding adaptive control strategy through the scheme determination module 240 and the drive control module 250 when the health trend coefficient has not yet reached the serious threshold in the early stage of wear. For example, when the system detects a slight wear trend on the tooth surface, the drive axle's speed ratio switching strategy or clutch engagement parameters can be automatically adjusted to soften the transmission process, thereby effectively slowing down the wear process and extending the service life of the components. Based on the health trend, the system-level adaptive control significantly improves the reliability, durability and driving smoothness of the drive axle, avoiding performance degradation and potential component damage caused by the accumulation of small errors, and providing more intelligent and reliable protection for the long-term stable operation of the vehicle.

[0078] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions described in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the present application.

Claims

1. An adaptive control method for a planetary gear continuously variable transmission drive axle, characterized in that, include: Collect vibration and impact signals from the planetary gear drive axle housing; The vibration and impact signals are processed to determine the transient impact characteristics related to the wear of the planetary gear tooth surface; The health trend of the planetary gear tooth surface is evaluated using the transient impact characteristics, and a health trend coefficient is obtained. Based on the health trend coefficient and the trend coefficient threshold, a drive axle control scheme is determined; A drive axle control scheme is used to control the planetary gear continuously variable transmission drive axle to achieve adaptive control of the drive axle.

2. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 1, characterized in that, The step of collecting vibration and impact signals on the planetary gear drive axle housing includes: Collect raw vibration and impact signals from the planetary gear drive axle housing; The original vibration and impact signal is subjected to noise removal processing to obtain the denoised original vibration and impact signal; The original vibration and impact signal after noise reduction is processed by analog-to-digital conversion to obtain a digital vibration and impact signal. The vibration and impact digital signal is filtered to obtain the vibration and impact signal.

3. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 1, characterized in that, The steps for performing signal feature processing on the vibration and impact signal to determine the transient impact characteristics related to the wear of the planetary gear tooth surface include: Extract the instantaneous signal amplitude of the vibration and impact signal; The instantaneous signal amplitude is compared with the signal amplitude threshold to obtain the instantaneous signal comparison value; Based on the comparison value between the vibration and impact signal and the instantaneous signal, each segment of the vibration and impact signal is determined; Feature extraction was performed on each vibration and impact signal to determine the transient impact characteristics related to the wear of the planetary gear tooth surface.

4. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 1, characterized in that, The steps for assessing the health trend of the planetary gear tooth surface and obtaining the health trend coefficient using the transient impact characteristics include: Extract the impact amplitude, high-frequency energy ratio, and characteristic temperature rise value from the transient impact characteristics; Based on the impact amplitude, high-frequency energy ratio, and characteristic temperature rise, the health trend of the planetary gear tooth surface is evaluated to obtain a health trend coefficient.

5. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 4, characterized in that, The steps for assessing the health trend of the planetary gear tooth surface and obtaining the health trend coefficient based on the impact amplitude, high-frequency energy ratio, and characteristic temperature rise value include: The impact amplitude is compared with a preset standard impact amplitude to obtain the impact amplitude ratio; The energy ratio is obtained by comparing the high-frequency energy ratio with the preset standard high-frequency energy ratio. The characteristic temperature rise value is compared with the preset standard temperature rise value to obtain the temperature rise ratio. The health trend of planetary gear tooth surfaces is evaluated based on the impact amplitude ratio, energy ratio, and temperature rise ratio, and a health trend coefficient is obtained.

6. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 1, characterized in that, The steps for determining the drive axle control scheme based on the health trend coefficient and the trend coefficient threshold include: Response analysis is performed on the health trend coefficient to determine the response parameters of the current drive axle; The response parameters of the current drive axle are compared with the trend coefficient threshold to obtain the response deviation value; Using a pre-defined drive axle control library, the response deviation value is matched to determine the drive axle control scheme.

7. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 6, characterized in that, The step of using a preset drive axle control library to perform scheme matching on response deviation values ​​and determine the drive axle control scheme includes: Using the response deviation value, the transient impact matching characteristics of the planetary gear set and the slip-friction matching state of the clutch are obtained from the preset drive axle control library; Based on the transient impact matching characteristics of the planetary gear set and the slip friction matching state of the clutch, the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch are determined. Based on the softening adjustment coefficients of the planetary gear set and the clutch, the drive axle control scheme is determined.

8. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 7, characterized in that, Based on the transient impact matching characteristics of the planetary gear set and the slip friction matching state of the clutch, the steps for determining the softening adjustment coefficient of the planetary gear set and the softening adjustment coefficient of the clutch include: A multi-dimensional analysis of the transient impact matching characteristics of the planetary gear set was performed to obtain the matching characteristic analysis results of the planetary gear set. A multi-dimensional analysis of the slip-friction matching state of the clutch is performed to obtain the clutch matching state analysis results; Based on the matching characteristic analysis results of the planetary gear set, the wear degree of the planetary gear set is determined; Based on the analysis results of the clutch's matching status, the degree of clutch wear is determined; Based on the wear levels of the planetary gear set and the clutch, the softening adjustment coefficients of the planetary gear set and the clutch are determined.

9. The adaptive control method for a planetary gear continuously variable transmission drive axle according to claim 1, characterized in that, After controlling the planetary gear continuously variable transmission drive axle using a drive axle control scheme to complete the adaptive control of the drive axle, the process also includes: Obtain the health trend control score after controlling the planetary gear continuously variable transmission drive axle; Based on the health trend control score, the control indicators for the planetary gear continuously variable transmission drive axle are determined. If the control indicators fail to meet the requirements, an alarm will be issued.

10. An adaptive control system for a planetary gear continuously variable transmission drive axle, characterized in that, The system includes: The signal acquisition module is used to acquire vibration and impact signals from the planetary gear drive axle housing. The feature processing module is used to perform signal feature processing on the vibration and impact signal to determine the transient impact features related to the wear of the planetary gear tooth surface; The coefficient evaluation module is used to evaluate the health trend of the planetary gear tooth surface using the transient impact characteristics, and obtain the health trend coefficient. The scheme determination module is used to determine the drive axle control scheme based on the health trend coefficient and the trend coefficient threshold. The drive control module uses a drive axle control scheme to control the planetary gear continuously variable transmission drive axle in order to achieve adaptive control of the drive axle.

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