Method and system for measuring inclination angle of overhead working truck
By constructing early warning values for vibration disturbance instability and stable attenuation, and combining them with filtering algorithms, the problem of inaccurate tilt angle measurement caused by mechanical vibration of aerial work platforms was solved, thereby improving the safety and real-time performance of aerial work platforms.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-05
- Publication Date
- 2026-04-07
AI Technical Summary
Noise interference caused by mechanical vibration during the operation of aerial work platforms can lead to inaccurate measurements by tilt sensors, making it impossible to capture changes in vehicle tilt in real time, thus affecting safety and work efficiency.
By integrating the frequency domain vibration energy and the time domain tilt oscillation characteristics, a vibration disturbance instability is constructed, its changing trend and differences are analyzed, a stable attenuation early warning value is generated, and adaptive denoising is performed by combining Kalman filtering and low-pass filtering.
Precisely quantify mechanical vibration interference, reduce false alarm rate, improve safety and operational continuity, and achieve a balance between real-time response to tilt changes and safety.
Smart Images
Figure CN121804428A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of high-altitude operation vehicle inclination angle measurement, and particularly relates to a high-altitude operation vehicle inclination angle measurement method and system. BACKGROUND
[0002] With the increasingly wide application of high-altitude operation vehicles, the risk of side tilting instability caused by the lifting of the center of gravity during the lifting of the operation platform of the high-altitude operation vehicle poses a severe challenge to safety. Therefore, accurate inclination angle measurement is crucial, and monitoring technology has developed from a traditional bubble level to an electronic inclination sensor and now to an integrated intelligent monitoring system. These advances not only ensure the safety of personnel and equipment and prevent side tilting accidents, but also significantly improve operation efficiency and quality.
[0003] The mechanical vibration of the high-altitude operation vehicle can interfere with the inclination sensor and superimpose high-frequency noise on the measurement signal. Current digital filtering algorithms, such as low-pass or Kalman filtering, can suppress noise, but there is an inherent contradiction: to pursue filtering effect and enhance suppression, a significant response delay and phase lag will be introduced. This delay results in the inability to capture the real inclination change of the high-altitude operation vehicle in real time, and reduces the real-time performance of the inclination change of the high-altitude operation vehicle body and the safety of the operation of the high-altitude operation vehicle. SUMMARY
[0004] To solve the above technical problems, the purpose of the application is to provide a high-altitude operation vehicle inclination angle measurement method and system, and the technical solution is as follows: In a first aspect, the application provides a high-altitude operation vehicle inclination angle measurement method, which comprises the following steps: Real-time acquisition of the inclination angle during the operation of the high-altitude operation vehicle; Based on the energy distribution of the inclination angle in the frequency domain at all times before each time, the vibration energy of the high-altitude operation vehicle at each time is determined. At each time before the time, the inclination angle fluctuation characteristic value of the high-altitude operation vehicle at each time is determined based on the dispersion degree of the inclination angle at all times within the neighborhood of any time, and the vibration energy is combined to determine the vibration interference instability degree of the high-altitude operation vehicle at each time; By analyzing the change trend of the vibration interference instability degree at all times before each time, the vibration reference strength of the high-altitude operation vehicle at each time is determined. Based on the difference between the vibration interference instability degrees of all adjacent times before each time, the vibration fluctuation degree of the high-altitude operation vehicle at each time is determined, and the vibration reference strength is combined to determine the smooth decay early warning value of the high-altitude operation vehicle at each time; Based on the smooth decay early warning value, the inclination angle during the operation of the high-altitude operation vehicle is denoised.
[0005] Preferably, the determination method of the vibration energy of the high-altitude operation vehicle at each time is: Obtaining the spectrum of the tilt angle at all times before each time, and taking the total energy in a preset frequency band in the spectrum as the vibration energy of the aerial work platform at each time.
[0006] Preferably, the method for determining the tilt angle fluctuation characteristic value of the aerial work platform at each time comprises: Taking the dispersion degree of the tilt angle at all times in the neighborhood of any time before each time as the tilt angle dispersion value at the any time; Taking the mean value of the tilt angle dispersion values at all times before each time as the tilt angle fluctuation characteristic value of the aerial work platform at each time.
[0007] Preferably, the vibration interference instability degree of the aerial work platform at each time is the positive fusion result of the vibration energy and the tilt angle fluctuation characteristic value of the aerial work platform at each time.
[0008] Preferably, the method for determining the vibration reference intensity of the aerial work platform at each time comprises: Applying a smoothing algorithm to the vibration interference instability degrees at each time and all times before each time, and taking the smoothed value of the vibration interference instability degree at each time as the vibration reference intensity of the aerial work at each time.
[0009] Preferably, the vibration fluctuation degree of the aerial work platform at each time is the mean value of the differences between the vibration interference instability degrees at all adjacent times before each time.
[0010] Preferably, the smooth decay early warning value of the aerial work platform at each time is the positive fusion result of the vibration reference intensity and the vibration fluctuation degree of the aerial work platform at each time.
[0011] Preferably, the method for denoising the tilt angle of the aerial work platform during work based on the smooth decay early warning value comprises: Comparing the sizes of the smooth decay early warning value and preset first and second threshold values, respectively, and adopting different denoising methods to denoise the tilt angle of the aerial work platform during work.
[0012] Preferably, the method for denoising the tilt angle of the aerial work platform during work by adopting different denoising methods comprises: If the smooth attenuation early warning value of the aerial work platform at the current moment is located between the preset first threshold value and the preset second threshold value, the Kalman filter algorithm is used to denoise the tilt angle of the aerial work platform at the current moment, otherwise, the low-pass filter is used to denoise the tilt angle of the aerial work platform at the current moment, wherein the preset first threshold value is smaller than the preset second threshold value. In the second aspect, the embodiment of the present application also provides an aerial work platform tilt angle measurement system, which comprises a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the steps of the aerial work platform tilt angle measurement method of any one of the above aspects when executing the computer program.
[0013] The present application has at least the following beneficial effects: The present application fuses the frequency domain vibration energy and the time domain tilt angle fluctuation characteristics to construct the vibration interference instability degree, which can accurately quantify the comprehensive interference intensity of mechanical vibration on the measurement result, thereby effectively distinguishing the real instability risk and the signal distortion caused by vibration, helping to reduce the false alarm rate of the aerial work platform caused by noise interference, and improving the safety and continuity of the aerial work. Further, the present application analyzes the trend and change rate of the vibration interference instability degree, constructs the vibration reference intensity and the vibration fluctuation degree respectively, and fuses the two to generate the smooth attenuation early warning value, which can comprehensively evaluate the overall instability risk from the average interference level and the instantaneous change intensity, thereby more accurately identifying the sudden instability. Finally, the present application constructs the adaptive filtering mechanism through the smooth attenuation early warning value, which can intelligently switch the optimal denoising strategy according to the dynamic instability risk of the aerial work platform: maintaining fast response in safe working conditions, prioritizing data reliability in dangerous working conditions, and achieving the best balance between filtering strength and response sensitivity through dynamic adjustment of Kalman filter parameters in transition working conditions, thereby effectively solving the problem that the traditional filtering method is difficult to balance real-time and accuracy in complex working conditions, and improving the real-time of the tilt change of the aerial work platform body and the safety of the aerial work. BRIEF DESCRIPTION OF DRAWINGS
[0014] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creating any creative labor.
[0015] Figure 1 A step flowchart of an aerial work platform tilt angle measurement method provided by an embodiment of the present application; Figure 2A smooth attenuation early warning value extraction process schematic diagram provided by an embodiment of the present application. DETAILED DESCRIPTION
[0016] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined purposes, the specific embodiments, structures, features and effects of the high-altitude work vehicle inclination angle measurement method and system according to the present application are described in detail as follows. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.
[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.
[0018] The specific scheme of the high-altitude work vehicle inclination angle measurement method and system provided by the present application is described in detail below with reference to the accompanying drawings.
[0019] Please refer to Figure 1 which shows the step flowchart of a high-altitude work vehicle inclination angle measurement method provided by an embodiment of the present application, which includes the following steps: Step S1: Real-time acquisition of the inclination angle during the working process of the high-altitude work vehicle.
[0020] A high-performance MEMS inclination sensor is installed on the chassis of the high-altitude work vehicle to collect the inclination angle during the working process of the high-altitude work vehicle in real time. A rigid connecting piece is used to install the secondary sensor on the main beam of the chassis close to the rotation center, so that the measurement reference and the inclination plane of the whole vehicle are consistent, and the inclination angle change of the vehicle body caused by the unevenness of the ground, the sinking of the outrigger and the change of the load of the working platform can be detected sensitively. The data acquisition frequency is f, which ensures that the inclination angle change process of the vehicle body is tracked quickly. All collected data are normalized to ensure that each group of collected data can be compared and analyzed under the same reference system.
[0021] It should be noted that the value of the data acquisition frequency f is artificially set, and in the present embodiment, the value of the data acquisition frequency is 20Hz. In actual application, as other implementation manners, the implementer can also set it himself according to the specific situation, and the present embodiment does not make special limitation.
[0022] It should be noted that there are many commonly used normalization methods, and in the embodiment, the maximum and minimum value normalization method is used for normalizing the inclination angle. In actual application, as an alternative, the implementer can use other normalization methods such as z-score standardization method according to specific conditions. The selection of the normalization method is not particularly limited in the embodiment.
[0023] The maximum and minimum value normalization method is a known technology, and the specific process of normalizing data using the method will not be described again.
[0024] Step S2: determining the vibration energy of the aerial work platform at each time point based on the energy distribution of the inclination angle in the frequency domain at all time points before the time point; before each time point, determining the inclination angle fluctuation characteristic value of the aerial work platform at the time point based on the dispersion degree of the inclination angle at any time point and all time points in the neighborhood of the time point, and determining the vibration interference instability degree of the aerial work platform at the time point in combination with the vibration energy.
[0025] Due to the mechanical vibration generated by the engine operation, chassis adjustment and operation platform action during the operation of the aerial work platform, a large amount of high-frequency noise is mixed in the original data collected by the inclination sensor, which causes serious fluctuation and distortion of the measured inclination angle. This not only causes false alarms of the control system and interrupts the operation, but also more likely covers up the real instability risk and forms a safety hazard.
[0026] Therefore, in the embodiment, the vibration energy of the aerial work platform at each time point is determined based on the energy distribution of the inclination angle in the frequency domain at all time points before the time point; before each time point, the inclination angle fluctuation characteristic value of the aerial work platform at the time point is determined based on the dispersion degree of the inclination angle at any time point and all time points in the neighborhood of the time point, and the vibration interference instability degree of the aerial work platform at the time point is determined in combination with the vibration energy, so as to measure the total interference strength of the vibration noise on the measurement result of the inclination sensor and the unreliable degree of the inclination angle. The specific process is as follows: Firstly, in the embodiment, the vibration energy of the aerial work platform at each time point is determined based on the energy distribution of the inclination angle in the frequency domain at all time points before the time point, and specifically: In the embodiment, the tilt angles at all times before each time are taken as the input of the fast Fourier transform algorithm, the sampling rate is set to 100 Hz, the frequency spectrum diagram is output, and the total energy in the preset frequency band in the frequency spectrum diagram is taken as the vibration energy of the aerial work vehicle at each time, which is used to represent the instantaneous intensity of the mechanical vibration interference on the tilt angle in the 5-15 Hz frequency band. The greater the vibration energy, the more intense the mechanical vibration experienced by the aerial work vehicle, the more seriously the signal output by the tilt angle sensor is polluted, and the higher the risk of distortion of the tilt angle measurement value. Conversely, the smaller the vibration energy, the more stable the working condition of the aerial work vehicle, the weaker the mechanical vibration, the lower the degree of pollution of the signal output by the tilt angle sensor, and the lower the risk of distortion of the tilt angle measurement value. The result can better reflect the true tilt state of the vehicle.
[0027] It should be noted that the value of the preset frequency band is artificially set. In the embodiment, the value of the preset frequency band is 5-15 Hz. The reason for selecting this frequency band is that this frequency band accurately covers the main mechanical vibration energy excited by the operation of large structural components such as the engine of the vehicle. By setting the frequency band in this range, the vibration intensity can be effectively quantified, and it can be distinguished from the ultra-low frequency attitude signal representing the slow change of the real vehicle body and other high-frequency electromagnetic noise with weak energy, thereby achieving accurate identification of interference noise.
[0028] The fast Fourier transform algorithm is a known technology, and the specific process of obtaining the frequency spectrum diagram will not be described again.
[0029] Further, during the dynamic operation process of the aerial work vehicle, the tilt angle sensor outputs an angle signal, and the angle signal output by the tilt angle sensor has a relatively obvious instantaneous jump. The time of the instantaneous fluctuation is short, but there is a fluctuation of several degrees. Therefore, in actual application, it is easy to cause the phenomenon that the system judges that the vehicle body suddenly tilts and starts the safety locking function in time to terminate the current operation process. Therefore, the tilt angle fluctuation characteristic value of the aerial work vehicle at each time is determined based on the dispersion degree of the tilt angle at any time and all times in the neighborhood thereof in the embodiment. Specifically: The dispersion degree of the tilt angle at any time and all times in the neighborhood thereof before each time is denoted as the tilt angle dispersion value at any time; The mean value of the tilt angle dispersion values at all times before each time is taken as the tilt angle fluctuation characteristic value of the aerial work vehicle at each time.
[0030] It should be noted that the division process of the neighborhood is that 20 times before any time are taken as the neighborhood of any time. In actual application, the implementer can also set the neighborhood division mode and neighborhood range according to the specific circumstances as other implementation manners, and the embodiment does not have special limitations.
[0031] It should be noted that there are many ways to measure the degree of data dispersion. In the present embodiment, the coefficient of variation of the inclination angle at any time and all times in its neighborhood is taken as the degree of dispersion of the inclination angle at any time and all times in its neighborhood. In actual application, as an alternative, the implementer can also use other methods to measure the degree of data dispersion, such as standard deviation or variance, according to the specific circumstances. The present embodiment does not make special restrictions on the selection of the method for measuring the degree of data dispersion.
[0032] The calculation method of the coefficient of variation is a known technology, and the specific calculation process is not described again.
[0033] According to the inclination fluctuation characteristic value of the aerial work platform at each time, it can be understood that the inclination fluctuation characteristic value is used to measure the dispersion and instability degree of the inclination angle in the time domain, and reflects the average fluctuation intensity of the inclination angle. If the dispersion degree of the inclination angle at all times before the current time is greater, i.e., the inclination fluctuation characteristic value is greater, it means that the inclination angle reading fluctuates more violently in a short time, indicating that the violent sliding of the boom or the strong resonance of the engine during the operation of the aerial work platform interferes with the inclination angle reading, causing instantaneous jump of the inclination angle, thereby triggering false alarm of the aerial work platform control system, resulting in unnecessary interruption of operation. On the contrary, if the dispersion degree of the inclination angle at all times before the current time is smaller, i.e., the inclination fluctuation characteristic value is smaller, it means that the inclination angle reading fluctuates more gently in a short time, indicating that the operation of the boom and the running of the engine have little interference on the inclination angle reading, and the inclination angle does not have obvious instantaneous jump, thereby ensuring the accuracy of the control system and avoiding unnecessary interruption of operation.
[0034] Further, the present embodiment determines the vibration interference instability degree of the aerial work platform at each time based on the inclination fluctuation characteristic value of the aerial work platform at each time and the vibration energy. In the present embodiment, the result of positively fusing the vibration energy and the inclination fluctuation characteristic value of the aerial work platform at each time is taken as the vibration interference instability degree of the aerial work platform at each time.
[0035] It should be understood that positive fusion refers to combining two or more indicators together through addition or multiplication, so as to obtain a comprehensive indicator, thereby more comprehensively and accurately evaluating a phenomenon or problem. This fusion method is not limited to simple arithmetic operation, but can also include more complex statistical models and analysis methods, which can be selected by the implementer according to the specific circumstances, and the present embodiment does not make special restrictions.
[0036] Preferably, as an implementation form, in the embodiment, the product of the vibration energy of the aerial work platform at each moment and the inclination angle fluctuation characteristic value is taken as the vibration interference instability degree of the aerial work platform at each moment; in actual application, as another implementation form, the implementer can also use other positive fusion methods such as sum according to specific conditions, and the embodiment does not make special limitations.
[0037] According to the vibration interference instability degree of the aerial work platform at each moment, it can be understood that the vibration interference instability degree comprehensively evaluates the influence of the vibration noise on the inclination angle measurement in the working process of the aerial work platform by fusing the frequency domain and time domain double information. If the vibration energy of the aerial work platform at the current moment is larger, it indicates that the vibration noise interferes with the accuracy of the inclination angle reading, and therefore, the corresponding vibration interference instability degree is also larger. At the same time, if the inclination angle fluctuation characteristic value of the aerial work platform at the current moment is larger, the corresponding vibration interference instability degree is also larger, which indicates that the vibration noise causes the inclination angle to fluctuate, so that the measured value of the inclination angle deviates from the actual value, thereby affecting the normal work of the aerial work platform. On the contrary, if the vibration energy of the aerial work platform at the current moment is smaller, it indicates that the vibration noise weakly interferes with the accuracy of the inclination angle reading, and therefore, the corresponding vibration interference instability degree is also smaller. At the same time, if the inclination angle fluctuation characteristic value of the aerial work platform at the current moment is smaller, the corresponding vibration interference instability degree is also smaller, which indicates that the vibration noise does not cause obvious angle fluctuation, so that the measured value of the inclination angle is closer to the actual value.
[0038] At this point, the embodiment constructs the vibration interference instability degree by fusing the frequency domain vibration energy and the time domain inclination angle fluctuation characteristic, which can accurately quantify the comprehensive interference intensity of mechanical vibration on the measurement result, thereby effectively distinguishing the real instability risk and the signal distortion caused by vibration, helping to reduce the false alarm rate of the aerial work platform caused by noise interference, and improving the safety and continuity of the aerial work.
[0039] Step S3: determining the vibration reference intensity of the aerial work platform at each moment by analyzing the change trend of the vibration interference instability degree at all moments before each moment; determining the vibration fluctuation degree of the aerial work platform at each moment based on the difference between the vibration interference instability degrees of all adjacent moments before each moment, and determining the smooth decay early warning value of the aerial work platform at each moment in combination with the vibration reference intensity.
[0040] When the aerial work platform is working, the inclination angle measurement data is dithered and distorted under the action of vibration and impact, the actual stability of the aerial work platform cannot be accurately judged, false positives or ignoring dangers are prone to occur, and although the vibration interference instability degree can represent the strength of the vibration, it is also noisy and short-term fluctuating, and cannot obtain continuous stable data trend; in addition, the change rate caused by the vibration force cannot be judged, and it is not easy to make a quick response and alarm for sudden instability.
[0041] Therefore, the embodiment further determines the vibration reference strength of the aerial work platform at each moment by analyzing the change trend of the vibration interference instability degree at all moments before each moment; determines the vibration fluctuation degree of the aerial work platform at each moment based on the difference between the vibration interference instability degrees of all adjacent moments before each moment, and determines the smooth decay early warning value of the aerial work platform at each moment in combination with the vibration reference strength, and the specific process is as follows: In the embodiment, first, the vibration reference strength of the aerial work platform at each moment is determined by analyzing the change trend of the vibration interference instability degree at all moments before each moment, and specifically: In the embodiment, the vibration interference instability degrees at each moment and all moments before each moment are taken as the input of the smoothing algorithm, wherein the smoothing factor is set to 0.1 in the embodiment to balance the recent data and historical fluctuations, avoid excessive smoothing leading to delayed response, and take the smoothed value of the vibration interference instability degree at each moment as the vibration reference strength of the aerial work platform at each moment.
[0042] It should be noted that there are many commonly used smoothing algorithms, and the exponential moving average algorithm is used to obtain the smoothed value of the vibration interference instability degree of the aerial work platform at each moment in the embodiment, and in actual application process, as other implementation manners, the implementer can also use other smoothing algorithms according to specific circumstances, and the embodiment does not make special limitation.
[0043] Among them, the exponential moving average algorithm is a known technology, and the specific process of smoothing data using the exponential moving average algorithm will not be repeated.
[0044] According to the vibration reference intensity of the aerial work platform at each time, it can be understood that the vibration reference intensity is used to evaluate the interference level of the recent vibration interference on the tilt angle measurement accuracy, and represents the vibration interference intensity that the aerial work platform chassis bears after filtering out short-term glitches. If the smoothed value of the aerial work platform vibration interference instability degree at the current time is larger, it indicates that the aerial work platform as a whole is in a higher vibration level in a period of time, and the corresponding vibration reference intensity is larger, and therefore, measures need to be taken to suppress the interference of vibration noise. Conversely, if the smoothed value of the aerial work platform vibration interference instability degree at the current time is smaller, it indicates that the aerial work platform as a whole is in a lower vibration level in a period of time, and the corresponding vibration reference intensity is smaller, and therefore, excessive noise suppression measures are not needed.
[0045] However, only relying on the smoothed value cannot fully reflect the instantaneous change, and therefore it is difficult to determine whether vibration instantaneous instability occurs when the rapid tilt fluctuates. In order to solve this problem, the embodiment determines the vibration fluctuation degree of the aerial work platform at each time based on the change rate of the vibration interference instability degree between all adjacent times before each time, and specifically: In the embodiment, the mean value of the difference of the vibration interference instability degree between all adjacent times before each time is taken as the vibration fluctuation degree of the aerial work platform at each time, which is used to represent the degree of change in the vibration interference level. If the difference of the vibration interference instability degree between all adjacent times before the current time is larger, the corresponding vibration fluctuation degree is also larger, which indicates that the vibration level changes very quickly in a short time, indicating that the aerial work platform may be experiencing a sharp working condition switching, i.e., in a higher average vibration interference level, such as rapid start and stop of the boom, and the vibration interference is also rapidly fluctuating, and the overall dynamic stability is poor, and the risk of control misjudgment of the aerial work platform due to the deviation of the tilt angle from the actual value caused by the vibration interference is higher. Conversely, if the difference of the vibration interference instability degree between all adjacent times before the current time is smaller, the corresponding vibration fluctuation degree is also smaller, which indicates that the vibration level changes smoothly in a short time, indicating that the working condition of the aerial work platform is stable and does not experience a sharp working condition switching, and the overall dynamic stability is good, and the tilt angle measurement value is less affected by the vibration interference, thereby reducing the risk of control misjudgment of the aerial work platform.
[0046] It should be noted that there are many methods for measuring the difference between data. In the embodiment, the absolute difference of the vibration interference instability degree between all adjacent times before each time is taken as the difference of the vibration interference instability degree between all adjacent times before each time. In actual application, as other implementation manners, the implementer can also use other methods for measuring the difference between data, such as the square or ratio of the difference, and the embodiment does not make special limitations on the selection of the method for measuring the difference between data.
[0047] Further, the embodiment is based on the vibration fluctuation degree of the aerial work platform at each time, and determines the stable attenuation early warning value of the aerial work platform at each time in combination with the vibration reference intensity, specifically: In the embodiment, the result of positively fusing the vibration reference intensity and the vibration fluctuation degree of the aerial work platform at each time is taken as the stable attenuation early warning value of the aerial work platform at each time.
[0048] Preferably, the stable attenuation early warning value extraction process provided by the embodiment is as shown in Figure 2
[0049] Preferably, as an implementation manner, the product of the vibration reference intensity and the vibration fluctuation degree of the aerial work platform at each time is taken as the stable attenuation early warning value of the aerial work platform at each time in the embodiment, and in actual application, as other implementation manners, implementers can also adopt other positively fused methods such as sum in combination with specific conditions, and the embodiment does not make special limitation.
[0050] According to the stable attenuation early warning value of the aerial work platform at each time, it can be understood that the stable attenuation early warning value is used for comprehensively evaluating the overall instability risk of the aerial work platform under the joint action of the average vibration intensity and the dynamic change rate. If the vibration reference intensity of the aerial work platform at the current time is greater, it indicates that the vibration interference intensity borne by the chassis of the aerial work platform in the recent period is stronger, the accuracy of the tilt angle measurement value is lower, the corresponding stable attenuation early warning value is greater, and it indicates that the risk of the control misjudgment of the aerial work platform caused by the deviation of the tilt angle from the actual value due to the vibration interference is higher. At the same time, if the vibration fluctuation degree of the aerial work platform at the current time is greater, the stable attenuation early warning value is greater, which indicates that the vibration level changes very quickly in a short time, that is, the average vibration interference level is higher, and the risk of the control misjudgment of the aerial work platform caused by the deviation of the tilt angle from the actual value due to the vibration interference is higher. On the contrary, if the vibration reference intensity of the aerial work platform at the current time is smaller, it indicates that the vibration interference intensity borne by the chassis of the aerial work platform in the recent period is weaker, the accuracy of the tilt angle measurement value is higher, the corresponding stable attenuation early warning value is smaller, and it indicates that the risk of the control misjudgment of the aerial work platform caused by the deviation of the tilt angle from the actual value due to the vibration interference is lower. At the same time, if the vibration fluctuation degree of the aerial work platform at the current time is smaller, the stable attenuation early warning value is smaller, which indicates that the vibration level changes gently in a short time, and the risk of the control misjudgment of the aerial work platform caused by the deviation of the tilt angle from the actual value due to the vibration interference is also lower.
[0051] So far, by analyzing the trend and the change rate of the vibration interference instability, the vibration reference intensity and the vibration fluctuation degree are respectively constructed, and the smooth decay early warning value is generated by fusing the two, which can comprehensively evaluate the overall instability risk from the two dimensions of the average interference level and the instantaneous change intensity, solve the problem that a single index cannot reflect the dynamic stability, and more accurately identify the sudden instability.
[0052] Step S4: Based on the smooth decay early warning value, the tilt angle in the working process of the aerial work platform vehicle is denoised.
[0053] The continuous vibration generated in the processes of the aerial work platform vehicle driving, chassis adjustment and operation platform action can cause the vehicle body vibration, which is transmitted to the internal sensitive device of the tilt sensor, thereby generating a high-frequency acceleration signal irrelevant to the actual tilt angle, and further causing a large noise component to be added to the output result of the tilt sensor. Since the measurement result of the tilt sensor is a non-stationary signal caused by the vibration transmission of the vehicle body to the front and rear and left and right of the vehicle body, the controlled vehicle may not correctly determine its actual static state, which is easy to cause the tilt sensor measurement value to fluctuate greatly, cannot normally judge the actual state of the vehicle body, and causes false alarms, affecting construction; if the signal is delayed or wrong, it may cause the real out-of-control state to be unable to be judged, and the safety protection function is lost. The existing filtering algorithm cannot consider the time domain and frequency domain and the distinction of acceleration noise in the two frequency domains, and it is difficult to process the vibration interference caused by the movement of the vehicle body.
[0054] Therefore, based on the smooth decay early warning value, the tilt angle in the working process of the aerial work platform vehicle is denoised, specifically: In this embodiment, by comparing the sizes of the smooth decay early warning value and the preset first threshold value and the preset second threshold value, different denoising methods are used to denoise the tilt angle in the working process of the aerial work platform vehicle, that is: If the smooth decay early warning value of the aerial work platform vehicle at the current moment is located between the preset first threshold value and the preset second threshold value, the Kalman filtering algorithm is used to denoise the tilt angle of the aerial work platform vehicle at the current moment, and the core is to optimize the process noise covariance in the Kalman filtering algorithm based on the smooth decay early warning value, specifically: The process noise covariance at the current moment The expression is: In the formula, represents the smooth decay early warning value of the aerial work platform vehicle at the current moment; represents the reference process noise covariance calibrated by collecting the tilt angle variance under the engine idle condition of the aerial work platform vehicle; norm() represents a normalization function.
[0055] The calculation of the reference process noise covariance is a known technique and will not be described in detail.
[0056] If the smooth decay early warning value of the aerial work platform at the current time is less than the preset first threshold, a low-pass filter is used, and the cutoff frequency is set to 20 Hz to maintain the rapid response capability; If the smooth decay early warning value of the aerial work platform at the current time is greater than the preset second threshold, a low-pass filter is used, and the cutoff frequency is set to 5 Hz to maximize the noise suppression.
[0057] The preset first threshold is less than the preset second threshold, and the values of the preset first threshold and the preset second threshold are artificially set. In the present embodiment, the value of the preset first threshold is 0.2, and the value of the preset second threshold is 0.45. 0.2 represents the critical point of safety and stability, and a value lower than this indicates that the aerial work platform is weakly and stably vibrating, which can be considered as a safe working condition. Therefore, the fastest filtering strategy is used to ensure the control sensitivity. 0.45 is the warning line of danger and instability, and a value exceeding this means that the aerial work platform is suffering from severe and rapidly changing vibration interference, which faces a high risk of false or missed reports. Therefore, it is necessary to switch to a strong filtering mode to sacrifice the response speed to ensure data reliability.
[0058] According to the process noise covariance, the smooth decay early warning value plays a decisive positive adjustment role in the process noise covariance. It quantifies the average vibration intensity and change rate during the operation of the aerial work platform, and converts the smooth decay early warning value into an evaluation of the reliability of the Kalman filter prediction model. When the smooth decay early warning value increases, the Q value is correspondingly adjusted. A larger Q value will lead the filter to reduce the trust in the model prediction and instead rely more on real-time sensor measurements, thereby enhancing the rapid response capability to sudden real tilts, but at the cost of allowing more high-frequency noise to pass through. Conversely, when the smooth decay early warning value decreases, it indicates that the working condition of the aerial work platform tends to be stable, and the Q value is correspondingly adjusted. A smaller Q value will lead the filter to enhance the trust in the model prediction and believe that the state change of the aerial work platform conforms to its inherent dynamic law, thereby relying more on the model prediction results to smooth the sensor data.
[0059] So far, the present embodiment constructs an adaptive filtering mechanism through the smooth decay early warning value, which can intelligently switch the optimal denoising strategy according to the dynamic instability risk of the aerial work platform: maintain rapid response in safe working conditions, prioritize data reliability in dangerous working conditions, and achieve the best balance between filtering strength and response sensitivity by dynamically adjusting the Kalman filter parameters in transitional working conditions. Thus, the problem that traditional filtering methods are difficult to balance real-time and accuracy in complex working conditions is effectively solved, and the real-time of the body tilt change of the aerial work platform and the safety of the aerial work platform operation are improved.
[0060] Based on the same inventive concept as the above method, the embodiment of the present application also provides a high-altitude operation vehicle inclination angle measuring system, comprising a memory, a processor and a computer program stored in the memory and running on the processor, and the processor implements the steps of any one of the above high-altitude operation vehicle inclination angle measuring methods when executing the computer program.
[0061] It should be noted that the above-mentioned sequence of the embodiments of the present application is only for description, and does not represent the advantages and disadvantages of the embodiments. Moreover, the above-mentioned description is made for specific embodiments of the present application. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are possible or can be advantageous.
[0062] Each of the embodiments in the specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the difference from other embodiments.
[0063] The above-mentioned is only the preferred embodiment of the present application, and does not limit the present application. Any modification, equivalent replacement, improvement, etc. made within the principle of the present application shall be included in the protection scope of the present application.
Claims
1. A method for measuring the tilt angle of an aerial work platform, characterized in that, The method includes the following steps: Real-time acquisition of the tilt angle of the aerial work platform vehicle during its operation; Based on the energy distribution of the tilt angle in the frequency domain at all times prior to each time, the vibration energy of the aerial work platform at each time is determined; before each time, based on the dispersion of the tilt angle at any time and all times in its neighborhood, the tilt angle fluctuation characteristic value of the aerial work platform at each time is determined, and combined with the vibration energy, the vibration disturbance instability of the aerial work platform at each time is determined. By analyzing the changing trend of vibration disturbance instability at all times before each time, the vibration reference strength of the aerial work platform at each time is determined; based on the difference in vibration disturbance instability between all adjacent times before each time, the vibration fluctuation of the aerial work platform at each time is determined, and combined with the vibration reference strength, the steady attenuation warning value of the aerial work platform at each time is determined. Based on the aforementioned stable attenuation warning value, noise reduction is performed on the tilt angle of the aerial work vehicle during its operation.
2. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The method for determining the vibration energy of the aerial work platform vehicle at each time point is as follows: The spectrum of the tilt angle at all previous moments is obtained, and the total energy within the preset frequency band in the spectrum is taken as the vibration energy of the aerial work vehicle at each moment.
3. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The method for determining the tilt angle fluctuation characteristic value of the aerial work vehicle at each time point is as follows: The degree of dispersion of the tilt angle at any time before each time and at all times in its neighborhood is denoted as the tilt angle discrete value at any time. The mean of the discrete tilt angle values at all previous times is used as the tilt angle fluctuation characteristic value of the aerial work platform vehicle at each time point.
4. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The vibration disturbance instability of the aerial work platform at each time point is the result of the positive fusion of the vibration energy and tilt angle fluctuation characteristic value of the aerial work platform at each time point.
5. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The method for determining the vibration reference intensity of the aerial work vehicle at each time point is as follows: A smoothing algorithm is used to evaluate the vibration disturbance instability at each time point and all previous time points. The smoothed value of the vibration disturbance instability at each time point is used as the vibration reference intensity for high-altitude operations at each time point.
6. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The vibration fluctuation of the aerial work platform at each time point is the average of the differences in vibration disturbance instability between all adjacent time points before each time point.
7. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The stable attenuation warning value of the aerial work platform at each time point is the result of positive fusion of the vibration reference intensity and vibration fluctuation of the aerial work platform at each time point.
8. The method for measuring the tilt angle of an aerial work platform as described in claim 1, characterized in that, The noise reduction of the tilt angle of the aerial work platform vehicle during operation based on the stable attenuation warning value includes: By comparing the stable attenuation warning value with the preset first threshold and the preset second threshold, different denoising methods are used to denoise the tilt angle of the aerial work vehicle during its operation.
9. The method for measuring the tilt angle of an aerial work platform as described in claim 8, characterized in that, The method of using different noise reduction techniques to reduce the tilt angle of the aerial work platform during operation includes: If the current steady decline warning value of the aerial work platform is between the preset first threshold and the preset second threshold, then the Kalman filter algorithm is used to denoise the tilt angle of the aerial work platform at the current moment; otherwise, a low-pass filter is used to denoise the tilt angle of the aerial work platform at the current moment. The preset first threshold is less than the preset second threshold.
10. A tilt angle measurement system for an aerial work platform, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the aerial work platform tilt angle measurement method as described in any one of claims 1-9.