Real-time Monitoring System for the Operating Status of Fixture Tools Based on the Internet of Things
By setting up multiple sensors at each part to be detected in the fixture, collecting multiple vibration signals and analyzing them, the problem that traditional single sensors cannot fully reflect the vibration state of the fixture is solved, and comprehensive and accurate monitoring and fault prevention of the fixture are achieved.
Patent Information
- Application Number
- CN202510315010.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2045-03-18
AI Technical Summary
When traditional methods conduct real-time monitoring of fixtures, a single sensor cannot fully reflect the vibration status of the fixtures, resulting in inaccurate monitoring results and ineffective failure prevention.
The real-time monitoring system for operating status of the fixture tool based on the Internet of Things is used. By setting up different types of sensors at each part to be detected, multiple vibration signal sequences are collected, and these signals are analyzed through computer programs, the status score and fusion weight of each part to be detected are obtained, and the overall status score of the fixture is finally calculated.
It realizes comprehensive monitoring of the fixture, improves the accuracy of the monitoring, and can more accurately judge the operating status of the fixture, prevents failures, and avoids production interruptions.
Smart Images
Figure CN119848783B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of data processing, and in particular, to a real-time monitoring system for the operation status of a jig tooling based on the Internet of Things. Background Art
[0002] Jigs have a wide range of applications and important roles in industrial production. They can not only improve production efficiency and machining accuracy, but also ensure the consistency and stability of product quality. Traditional jig maintenance methods often rely on post-failure repairs, which are not only inefficient but may also lead to production interruptions and increased maintenance costs. Therefore, it is necessary to monitor jigs in real time to avoid the occurrence of failures.
[0003] Traditional methods use Internet of Things technology to collect vibration data of jigs in real time through sensors and data acquisition modules. By real-time monitoring and early warning of the vibration data during jig operation, potential fault hazards of the jigs can be detected in time, and corresponding preventive measures can be taken to avoid the occurrence of failures. However, traditional methods generally use a single sensor to collect vibration data at the connection between the jig and the workpiece, without considering the influence of vibration data from other parts. Due to the complex structure of the robotic arm, a single sensor cannot comprehensively reflect its vibration state, and the collected vibration data may not accurately reflect the true vibration state, resulting in inaccurate monitoring results and causing fault problems in production.
[0004] Therefore, how to comprehensively monitor jigs and improve the accuracy of monitoring has become an urgent problem to be solved. Summary of the Invention
[0005] In view of this, an embodiment of the present invention provides a real-time monitoring system for the operation status of a jig tooling based on the Internet of Things to solve the problem of how to comprehensively monitor jigs and improve the accuracy of monitoring.
[0006] An embodiment of the present invention provides a real-time monitoring system for the operation status of a jig tooling based on the Internet of Things, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the following method is implemented:
[0007] During the operation of the jig, at least two vibration signal sequences of each part to be detected at the current sampling moment are collected to obtain all vibration signal sequences of a preset number of parts to be detected;
[0008] For any set of vibration signal sequences, obtain the vibration signal at the current sampling moment in the any set of vibration signal sequences and denote it as the target signal. According to the fluctuation characteristics of the any set of vibration signal sequences, obtain the outlier of the target signal. According to the vibration signal type of the any set of vibration signal sequences and the difference in vibration signals between each part to be detected at the current sampling moment and the vibration signal sequences with the same vibration signal type as the any set of vibration signal sequences, obtain the state consistency index of the target signal;
[0009] According to the outlier and state consistency index of the target signal, obtain the state score of the target signal. According to the fluctuation characteristics of the any set of vibration signal sequences, obtain the fusion weight of the target signal;
[0010] Obtain the state score and fusion weight of the target signal in each set of vibration signal sequences. According to the state score and fusion weight of the target signal in each set of vibration signal sequences, obtain the overall state score of the fixture at the current sampling moment. According to the overall state score of the fixture at the current sampling moment, judge the operating state of the fixture at the current sampling moment.
[0011] The beneficial effects of the embodiments of the present invention compared with the prior art are:
[0012] During the operation of the fixture, at least two vibration signal sequences of each part to be detected at the current sampling moment are collected to obtain all vibration signal sequences of a preset number of parts to be detected. For any group of vibration signal sequences, the vibration signal at the current sampling moment in the any group of vibration signal sequences is recorded as the target signal. According to the fluctuation characteristics of the any group of vibration signal sequences, the outlier of the target signal is obtained. According to the type of vibration signal of the any group of vibration signal sequences and the difference in vibration signals between the vibration signal sequences of each part to be detected at the current sampling moment and the vibration signal sequences of the same type of vibration signal as the any group of vibration signal sequences, the state consistency index of the target signal is obtained. According to the outlier and state consistency index of the target signal, the state score of the target signal is obtained. According to the fluctuation characteristics of the any group of vibration signal sequences, the fusion weight of the target signal is obtained. The state scores and fusion weights of the target signals in each group of vibration signal sequences are obtained. According to the state scores and fusion weights of the target signals in each group of vibration signal sequences, the overall state score of the fixture at the current sampling moment is obtained. According to the overall state score of the fixture at the current sampling moment, the operation state of the fixture at the current sampling moment is judged. By collecting various vibration signals of different parts of the fixture, and obtaining the state score of each vibration signal according to the fluctuation characteristics of each group of vibration signal sequences and the difference in vibration signals between vibration signal sequences, and performing weighted fusion on the state scores of various vibration signals at the current sampling moment to obtain the overall state score of the fixture at the current sampling moment, the present invention not only realizes the comprehensive monitoring of the fixture, but also makes the judgment of the operation state of the fixture at the current sampling moment more accurate, realizing more comprehensive, intuitive and accurate monitoring of the fixture. Description of the Drawings
[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0014] Figure 1 It is a flowchart of a method for real-time monitoring of the operation state of a fixture tooling based on the Internet of Things provided in Embodiment 1 of the present invention;
[0015] Figure 2 It is an example diagram of a fixture provided in Embodiment 1 of the present invention. Detailed Embodiments
[0016] Embodiments of the present disclosure will be described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present disclosure, and should not be construed as limiting the present disclosure.
[0017] It should be noted that the terms "first", "second", etc. in the specification of the present disclosure and the above-mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present disclosure described here can be implemented in an order other than those illustrated or described here. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. On the contrary, they are only examples of devices and methods consistent with some aspects of the present disclosure.
[0018] In order to illustrate the technical solution of the present invention, specific embodiments will be used for illustration below.
[0019] An embodiment of the present invention provides a real-time monitoring system for the operating state of a fixture tooling based on the Internet of Things, including a processor and a memory. The processor executes the computer program of the memory to implement a real-time monitoring method for the operating state of a fixture tooling based on the Internet of Things, as Figure 1 shown. The method includes the following steps:
[0020] Step S101, during the operation of the fixture, collect at least two vibration signal sequences of each part to be detected at the current sampling moment, and obtain all vibration signal sequences of a preset number of parts to be detected.
[0021] In order to comprehensively monitor the fixture, in this embodiment, different types of sensors are set at each part to be detected of the fixture to collect various vibration signals of each part to be detected during the operation of the fixture. The parts to be detected in this embodiment are as Figure 2 shown, including but not limited to Figure 2 4 parts in the middle: Part 1 is the connection between the fixture and the workpiece, Part 2 is the connection between the fixture and the robotic arm, Part 3 is the lever of the robotic arm, and Part 4 is the connection of the robotic arm lever. A displacement sensor, a velocity sensor, and an acceleration sensor are set at each part to be detected. There is no limitation here, and it can be set according to the specific implementation scenario. In this embodiment, at a sampling frequency of once per second, three vibration signals of each part to be detected within 24 hours including the current sampling moment are collected. One vibration signal of one part to be detected forms a group of vibration signal sequences, and 12 groups of vibration signal sequences of 4 parts to be detected are obtained. There is no limitation here, and it can be set according to the specific implementation scenario.
[0022] Step S102: For any set of vibration signal sequences, obtain the vibration signal at the current sampling moment in the any set of vibration signal sequences, which is denoted as the target signal. According to the fluctuation characteristics of the any set of vibration signal sequences, obtain the outlier of the target signal. According to the vibration signal type of the any set of vibration signal sequences and the difference in vibration signals between each part to be detected at the current sampling moment and the vibration signal sequences with the same vibration signal type as the any set of vibration signal sequences, obtain the state consistency index of the target signal.
[0023] Since the motion trajectories of each part to be detected of the fixture are the same under the same operating state and mostly perform repetitive work, the obtained vibration signals are periodic. Moreover, since the workpieces used are of the same specification, the obtained vibration signals should fluctuate within a fixed range. If the vibration signal at the current sampling moment does not satisfy the periodicity of the vibration signals or the amplitude of the vibration signal is not within the fixed range, the vibration signal at the current sampling moment may be abnormal, and problems may occur in the part to be detected where the vibration signal is located. Therefore, for any set of vibration signal sequences, the vibration signal at the current sampling moment in the any set of vibration sequences is denoted as the target signal. The outlier of the target signal can be obtained according to the fluctuation characteristics of the any set of vibration signal sequences. The state of the part to be detected where the target signal is located can be judged through the outlier of the target signal, and then the operating state of the fixture can be judged.
[0024] Among them, the method for obtaining the outlier of the target signal according to the fluctuation characteristics of the any set of vibration signal sequences is as follows:
[0025] Obtain the vibration period of the any set of vibration signal sequences. According to the vibration period, divide the any set of vibration signal sequences into at least two sub-sequences;
[0026] Obtain the number of extreme points of each sub-sequence in the any set of vibration signal sequences, and obtain the absolute value of the first difference between the number of extreme points of the sub-sequence where the target signal is located and the number of extreme points of the first sub-sequence;
[0027] Obtain the position number of the target signal in the sub-sequence where the target signal is located, and form a first target sequence with the amplitudes of the vibration signals with the same position number as the target signal in each sub-sequence;
[0028] Obtain the first quartile and the third quartile in the first target sequence, calculate the first mean of the first quartile and the third quartile, obtain the first difference between the amplitude of the target signal and the first mean, and obtain the maximum value between the first difference and the constant 0;
[0029] Obtain the addition result of the absolute value of the first difference and the maximum value as the outlier of the target signal.
[0030] In one embodiment, first perform a Fourier transform on any set of vibration signal sequences to obtain the spectrogram of any set of vibration signal sequences. The Fourier transform belongs to the prior art and will not be elaborated here. In the spectrogram, obtain the vibration period of the vibration signal. According to the vibration period of the vibration signal, divide any set of vibration signal sequences into at least two subsequences according to the division method of forming a subsequence for each vibration signal in each vibration period. Use the derivative method to obtain the extreme points of each subsequence and obtain the number of extreme points of each subsequence. The derivative method belongs to the prior art and will not be elaborated here. Then obtain the position number of the target signal in the subsequence where the target signal is located. In each subsequence, obtain the amplitude of the vibration signal with the same position number as the target signal to form the first target sequence. Obtain the first quartile and the third quartile in the first target sequence. The quartile method belongs to the prior art and will not be elaborated here. Finally, calculate the outlier of the target signal according to the number of extreme points of each subsequence, the first quartile and the third quartile in the first target sequence, and the amplitude of the target signal:
[0031]
[0032] Among them, is the outlier of the target signal; A1 is the number of extreme points of the first subsequence; Ai is the number of extreme points of the subsequence where the target signal is located; i is the serial number of the subsequences divided from any set of vibration signal sequences; Q1 is the first quartile in the first target sequence; Q3 is the third quartile in the first target sequence; x is the amplitude of the target signal; | | is the absolute value symbol; max() is the maximum value function.
[0033] It should be noted that the greater the difference between the number of extreme points of the first subsequence and the number of extreme points of the subsequence where the target signal is located, the greater the possibility that the period of the vibration signal in the subsequence where the target signal is located is abnormal, the greater the outlier of the target signal, and the more likely the fixture is in an abnormal state; the greater the difference between the amplitude of the target signal and the mean value of the first quartile and the third quartile in the first target sequence, the greater the possibility that the amplitude of the target signal exceeds the fixed range of the vibration signal amplitude, the greater the outlier of the target signal, and the more likely the fixture is in an abnormal state.
[0034] During the operation of the fixture, although there are differences in the movement trajectories of different parts to be detected on the fixture, each part to be detected has its own fixed movement trajectory under the same movement state. Therefore, each part to be detected will have its own characteristics. For example, when the fixture is in the state of transporting the workpiece, the robotic arm moves horizontally and there is no obvious change vertically. At this time, there will be a horizontal displacement change in the lever of the robotic arm, and a vibration displacement signal can be monitored. Moreover, the movement of the robotic arm is generally a uniform change, so a vibration velocity signal can be monitored, but a vibration acceleration signal may not be monitored. At the same time, the vibration displacement at the front end of the lever near the connection between the fixture and the workpiece is greater than that at the rear end of the lever far from the connection between the fixture and the workpiece, but the vibration velocities of the two parts to be detected may be the same. At the same time, for some parts to be detected fixed by connection, the main moving part and the connecting part do not belong to the same part to be detected. The speed of the non-main moving part may be slightly lower than that of the main moving part, and affected by the passive force, the vibration signal may fluctuate slightly.
[0035] Therefore, according to the type of vibration signal in any group of vibration signal sequences, and the difference in vibration signals between each part to be detected at the current sampling moment and the vibration signal sequences with the same type of vibration signal as any group of vibration signal sequences, the state consistency index of the target signal can be obtained. The state of the part to be detected where the target signal is located can be judged through the state consistency of the target signal, and then the operation state of the fixture can be judged.
[0036] Among them, the method for obtaining the state consistency index of the target signal according to the type of vibration signal in any group of vibration signal sequences, and the difference in vibration signals between each part to be detected at the current sampling moment and the vibration signal sequences with the same type of vibration signal as any group of vibration signal sequences is as follows:
[0037] Since displacement sensors, velocity sensors and acceleration sensors are arranged at each part to be detected in this embodiment, the types of vibration signals include: vibration displacement signals, vibration velocity signals and vibration acceleration signals.
[0038] (1) When the type of vibration signal in any group of vibration signal sequences is a vibration displacement signal, set the connection between the fixture and the workpiece as the reference position, obtain the distance sequence composed of the distances between the positions of each part to be detected and the reference position, and in each group of vibration signal sequences with the same type of vibration signal as any group of vibration signal sequences, obtain the amplitudes of the vibration signals at the current sampling moment to form an amplitude sequence, and perform inverse ratio fitting on the amplitude sequence and the distance sequence to obtain the fitting inverse ratio function of amplitude and distance;
[0039] Obtain the first distance between the position of the part to be detected where the target signal is located and the reference position, obtain the fitting amplitude of the first distance in the fitting inverse proportional function, calculate the absolute value of the second difference between the amplitude of the target signal and the fitting amplitude, and obtain the reciprocal of the absolute value of the second difference as the state consistency index of the target signal.
[0040] In one embodiment, when the vibration signal type of any group of vibration signal sequences is a vibration displacement signal, the amplitude of the vibration signal in any group of vibration signal sequences is the displacement amount. First, set the connection between the fixture and the workpiece as the reference position. The amplitudes of the vibration signals at the current sampling moment in each group of vibration signal sequences with the vibration signal type of vibration displacement signal form an amplitude sequence, and the distances between the positions of the parts to be detected corresponding to each group of vibration signal sequences with the vibration signal type of vibration displacement signal and the reference position form a distance sequence. Perform inverse proportion fitting on the amplitude sequence and the distance sequence to obtain the fitting inverse proportional function of the displacement amount of the part to be detected at the current sampling moment and its distance from the reference position. Inverse proportion fitting belongs to the prior art and will not be elaborated here. Then, obtain the distance between the position of the part to be detected where the target signal is located and the reference position, denoted as the first distance. Use the fitting inverse proportional function to obtain the fitting amplitude of the first distance. According to the fitting amplitude of the first distance and the actual amplitude of the target signal, calculate the state consistency index of the target signal:
[0041]
[0042] Among them, is the state consistency index of the target signal when the vibration signal type of any group of vibration signal sequences is a vibration displacement signal; C is the first distance; is the amplitude of the target signal; t is the current sampling moment; is the constant term in the fitting inverse proportional function; | | is the absolute value symbol.
[0043] It should be noted that the amplitude of the vibration signal in the vibration signal sequence of the vibration displacement signal type represents the displacement amount of the part to be detected where the vibration signal is located. represents the fitting amplitude (i.e., the fitting displacement amount) of the distance between the position of the part to be detected where the target signal is located and the reference position in the fitting inverse proportional function. represents the difference between the actual displacement amount of the target signal and the fitting displacement amount. The smaller, the more the actual displacement amount of the target signal conforms to the displacement amount that the part to be detected should have, the larger the state consistency index of the target signal, and the more normal the operating state of the fixture. The larger, the more the actual displacement amount of the target signal does not conform to the displacement amount that the part to be detected should have, the smaller the state consistency index of the target signal, and the more likely the fixture is in an abnormal state.
[0044] (2) When the vibration signal type of any group of vibration signal sequences is a vibration velocity signal, denote the subsequence where the target signal is located as the first target subsequence, divide the first target subsequence into at least one sequence segment according to a preset length, calculate the curvature of each sequence segment respectively, and correspondingly obtain the first curvature mean value;
[0045] Detect whether there is a displacement change of the part to be detected where any group of vibration signal sequences is located relative to the fixture. If there is no displacement change of the part to be detected where any group of vibration signal sequences is located relative to the fixture, then obtain the reciprocal of the first curvature mean value as the state consistency index of the target signal;
[0046] If there is a displacement change of the part to be detected where any group of vibration signal sequences is located relative to the fixture, then obtain the first phase of the target signal. In each group of vibration signal sequences with the same vibration signal type as any group of vibration signal sequences, obtain the phases of the vibration signals at the current sampling moment to form a second target sequence, obtain the phase with the highest frequency in the second target sequence, calculate the absolute value of the third difference between the first phase of the target signal and the phase with the highest frequency in the second target sequence, calculate the third addition result of the absolute value of the third difference and the constant 1, and obtain the mean value of the reciprocal of the third addition result and the reciprocal of the first curvature mean value as the state consistency index of the target signal.
[0047] In one embodiment, when the vibration signal type of any group of vibration signal sequences is a vibration velocity signal, first, mark the subsequence where the target signal is located as the first target subsequence. According to the division method of taking 3 vibration signals as a sequence segment, divide the first target subsequence into at least one sequence segment (when the number of vibration signals in the first target subsequence is less than 3, supplement with the vibration signals before the first target subsequence), which is not limited here and can be set according to the specific implementation scenario. Calculate the curvature of each sequence segment respectively, and obtain the mean value of the curvatures of all sequence segments, denoted as the first curvature mean value. Curvature belongs to the prior art and will not be elaborated here. Then, detect whether there is a displacement change of the part to be detected where any group of vibration signal sequences is located relative to the fixture. If there is no displacement change of the part to be detected where any group of vibration signal sequences is located relative to the fixture, confirm that the part to be detected where any group of vibration signal sequences is located is a non-primary motion part, and set the motion value of the non-primary motion part to 0, which is not limited here and can be set according to the specific implementation scenario. Calculate the state consistency index of the target signal according to the curvature of each sequence segment in the first target subsequence. If there is a displacement change of the part to be detected where any group of vibration signal sequences is located relative to the fixture, confirm that the part to be detected where any group of vibration signal sequences is located is a primary motion part, and set the motion value of the primary motion part to 1, which is not limited here and can be set according to the specific implementation scenario. Obtain the phase of the target signal, denoted as the first phase. In each group of vibration signal sequences where the vibration signal type is a vibration velocity signal, obtain the phase of the vibration signal at the current sampling moment to form a second target sequence, and obtain the phase with the highest frequency in the second target sequence. Calculate the state consistency index of the target signal according to the difference between the first phase and the phase with the highest frequency in the second target sequence, and the curvature of each sequence segment in the first target subsequence. The calculation formula of the state consistency index of the target signal is as follows:
[0048]
[0049] Wherein, is the state consistency index of the target signal when the vibration signal type of any group of vibration signal sequences is a vibration velocity signal; is the first curvature mean value; is the first phase; t is the current sampling moment; is the phase with the highest frequency in the second target sequence; P is the motion value; | | is the absolute value symbol.
[0050] It should be noted that the smaller the average value of the first curvature is, the smaller the fluctuation of the first target subsequence is, the more stable the vibration signal is, and the larger the state consistency index of the target signal is; since the speed of the fixture during operation is consistent under normal circumstances and the entire fixture has this speed, there will be no difference in the phase of the vibration signal. The smaller the difference between the first phase and the phase with the highest frequency in the second target sequence is, the more the running speed of the detected part where the target signal is located conforms to the normal speed, and the larger the state consistency index of the target signal is; the larger the state consistency index of the target signal is, the more normal the running state of the fixture is.
[0051] (3)When the vibration signal type of any group of vibration signal sequences is a vibration acceleration signal, denote the subsequence where the target signal is located as the second target subsequence, divide the second target subsequence into at least one sequence segment according to a preset length, calculate the curvature of each sequence segment respectively, and correspondingly obtain the average value of the second curvature.
[0052] Detect whether there is a displacement change of the detected part where any group of vibration signal sequences is located relative to the fixture. If there is no displacement change of the detected part where any group of vibration signal sequences is located relative to the fixture, obtain the reciprocal of the average value of the second curvature as the state consistency index of the target signal.
[0053] If there is a displacement change of the detected part where any group of vibration signal sequences is located relative to the fixture, obtain the second phase of the target signal. In each group of vibration signal sequences with the same vibration signal type as any group of vibration signal sequences, obtain the phase of the vibration signal at the current sampling moment to form a third target sequence, obtain the phase with the highest frequency in the third target sequence, calculate the absolute value of the fourth difference between the second phase of the target signal and the phase with the highest frequency in the third target sequence, calculate the fourth addition result of the absolute value of the fourth difference and the constant 1, and obtain the average value of the reciprocal of the fourth addition result and the reciprocal of the average value of the second curvature as the state consistency index of the target signal.
[0054] In an embodiment, when the vibration signal type of any group of vibration signal sequences is a vibration acceleration signal, according to the method for obtaining the state consistency index of the target signal when the vibration signal type of any group of vibration signal sequences is a vibration velocity signal, obtain the state consistency index of the target signal when the vibration signal type of any group of vibration signal sequences is a vibration acceleration signal.
[0055] Thus, the outlier and the state consistency index of the target signal are obtained.
[0056] Step S103: Obtain the status score of the target signal based on the outlier value and status consistency index of the target signal, and obtain the fusion weight of the target signal according to the fluctuation characteristics of any group of vibration signal sequences.
[0057] After obtaining the outlier value and status consistency index of the target signal, the status score of the target signal can be obtained based on the outlier value and status consistency index of the target signal, and then the fusion weight of the target signal can be obtained according to the fluctuation characteristics of any group of vibration signal sequences. The status of the part to be detected where the target signal is located is judged through the fusion weight and status score of the target signal, and then the operating status of the fixture at the current sampling moment is judged through the fusion of the status scores of various vibration signals of all parts to be detected at the current sampling moment.
[0058] Among them, the method for obtaining the status score of the target signal based on the outlier value and status consistency index of the target signal is as follows:
[0059] Normalize the outlier value of the target signal to obtain a normalized outlier value, calculate the subtraction result of the constant 1 and the normalized outlier value, calculate the second mean value of the subtraction result and the status consistency index of the target signal, and obtain a preset multiple of the second mean value as the status score of the target signal.
[0060] In an embodiment, the formula for calculating the status score of the target signal based on the outlier value and status consistency index of the target signal is:
[0061]
[0062] Among them, is the status score of the target signal; is the outlier value of the target signal; is the status consistency index of the target signal; v is the serial number of the vibration signal type; norm() is the normalization function; 10 is the preset multiple.
[0063] It should be noted that the smaller the outlier value of the target signal, the more it indicates that the target signal satisfies the periodicity of the vibration signal it is in or the amplitude of the target signal is within the normal range, and the larger the status score of the target signal; the larger the status consistency index of the target signal, the more it indicates that the part to be detected where the target signal is located conforms to the current proper motion state, and the larger the status score of the target signal; the larger the status score of the target signal, the more normal the operating state of the fixture.
[0064] Among them, the method for obtaining the fusion weight of the target signal according to the fluctuation characteristics of any group of vibration signal sequences is as follows:
[0065] Obtain the maximum amplitude in the subsequence where the target signal is located. In each group of vibration signal sequences, obtain the maximum amplitude in each subsequence at the current sampling moment and accumulate them to obtain the corresponding accumulated value. Calculate the ratio of the maximum amplitude in the subsequence where the target signal is located to the accumulated value as the fusion weight of the target signal.
[0066] In one embodiment, obtain the maximum amplitude in the subsequence where each vibration signal is located at the current sampling moment, and calculate the fusion weight of the target signal:
[0067]
[0068] where Y is the fusion weight of the target signal; is the maximum amplitude in the subsequence where the target signal is located; is the maximum amplitude in the subsequence where the e-th vibration signal is located at the current sampling moment; e is the serial number of the vibration signal sequence; E is the number of vibration signal sequences.
[0069] It should be noted that the larger the maximum amplitude in the subsequence where the target signal is located, the greater the influence on the target signal in the current operating state, and the greater the fusion weight of the target signal.
[0070] So far, the state score and fusion weight of the target signal are obtained.
[0071] Step S104: Obtain the state score and fusion weight of the target signal in each group of vibration signal sequences. According to the state score and fusion weight of the target signal in each group of vibration signal sequences, obtain the overall state score of the fixture at the current sampling moment. According to the overall state score of the fixture at the current sampling moment, judge the operating state of the fixture at the current sampling moment.
[0072] After obtaining the state score and fusion weight of the target signal, according to the method for obtaining the state score and fusion weight of the target signal, obtain the state score and fusion weight of the target signal (that is, each vibration signal of each part to be detected at the current sampling moment) in each group of vibration signal sequences. Then, according to the state score and fusion weight of the target signal in each group of vibration signal sequences, obtain the overall state score of the fixture at the current sampling moment and judge the operating state of the fixture at the current sampling moment.
[0073] Among them, the method for obtaining the overall state score of the fixture at the current sampling moment according to the state score and fusion weight of the target signal in each group of vibration signal sequences is as follows:
[0074] Based on the fusion weights of the target signals in each group of vibration signal sequences, the state scores of the target signals in all vibration signal sequences are weighted and summed to obtain the overall state score of the fixture at the current sampling moment.
[0075] In one embodiment, the formula for calculating the overall state score of the fixture at the current sampling moment is:
[0076]
[0077] Wherein, is the overall state score of the fixture at the current sampling moment; is the fusion weight of the e-th target signal at the current sampling moment; is the state score of the e-th target signal at the current sampling moment; e is the serial number of the vibration signal sequence; E is the number of vibration signal sequences; t is the current sampling moment.
[0078] It should be noted that the higher the state score of each target signal at the current sampling moment, the more normal each target signal is at the current sampling moment, the higher the overall state score of the fixture at the current sampling moment, and the more normal the operating state of the fixture.
[0079] After obtaining the overall state score of the fixture at the current sampling moment, the overall state score of the fixture at this time integrates the vibration signals of various vibration types of all parts to be detected in the fixture, and can monitor the operating state of the fixture more comprehensively, intuitively and accurately. Therefore, the operating state of the fixture at the current sampling moment can be judged by the overall state score of the fixture at the current sampling moment.
[0080] Specifically, set an overall state score threshold interval, which includes a first abnormal interval, a second abnormal interval, a third abnormal interval and a normal interval. The overall state score of the first abnormal interval is less than the overall state score of the second abnormal interval, the overall state score of the second abnormal interval is less than the overall state score of the third abnormal interval, and the overall state score of the third abnormal interval is less than the overall state score of the normal interval;
[0081] When the overall state score of the fixture at the current sampling moment is in the first abnormal interval, it is confirmed that the fixture is in a severe abnormal operating state;
[0082] When the overall state score of the fixture at the current sampling moment is in the second abnormal interval, it is confirmed that the fixture is in a moderate abnormal operating state;
[0083] When the overall state score of the fixture at the current sampling moment is in the third abnormal interval, it is confirmed that the fixture is in a mild abnormal operating state;
[0084] When the overall status score of the fixture at the current sampling moment is within the normal range, it is confirmed that the fixture is in a normal operating state.
[0085] In one embodiment, the overall status score threshold range is set to [0, 10], the first abnormal range is set to [0, 6), the second abnormal range is set to [6, 8), the third abnormal range is set to [8, 9), and the normal range is set to [9, 10]. There is no limitation here and it can be set according to specific implementation scenarios. When the overall status score of the fixture at the current sampling moment is within [0, 6), it is confirmed that the fixture is in a severely abnormal operating state, and measures such as maintenance treatment need to be taken for the fixture; when the overall status score of the fixture at the current sampling moment is within [6, 8), it is confirmed that the fixture is in a moderately abnormal operating state, and manual observation is required to determine whether the fixture has a fault; when the overall status score of the fixture at the current sampling moment is within [8, 9), it is confirmed that the fixture is in a slightly abnormal operating state, and the fixture needs to be continuously monitored. If the overall status score of the fixture after 3 - 5 sampling moments is within [9, 10], it is confirmed that the fixture is in a normal operating state. If the overall status score of the fixture after 3 - 5 sampling moments is not within [9, 10], manual observation and processing are required. There is no limitation here and it can be set according to specific implementation scenarios; when the overall status score of the fixture at the current sampling moment is within [9, 10], it is confirmed that the fixture is in a normal operating state.
[0086] In summary, in the embodiment of the present invention during the operation of the fixture, at least two vibration signal sequences of each part to be detected at the current sampling moment are collected to obtain all vibration signal sequences of a preset number of parts to be detected; for any group of vibration signal sequences, the vibration signal at the current sampling moment in the any group of vibration signal sequences is obtained as the target signal, according to the fluctuation characteristics of the any group of vibration signal sequences, the outlier of the target signal is obtained, according to the vibration signal type of the any group of vibration signal sequences, and the difference between the vibration signals between the vibration signal sequences of each part to be detected at the current sampling moment and the vibration signal sequences of the any group of vibration signal sequences with the same vibration signal type, the state consistency index of the target signal is obtained; according to the outlier and state consistency index of the target signal, the state score of the target signal is obtained, according to the fluctuation characteristics of the any group of vibration signal sequences, the fusion weight of the target signal is obtained; the state scores and fusion weights of the target signals in each group of vibration signal sequences are obtained, according to the state scores and fusion weights of the target signals in each group of vibration signal sequences, the overall state score of the fixture at the current sampling moment is obtained, and according to the overall state score of the fixture at the current sampling moment, the operation state of the fixture at the current sampling moment is judged. In the embodiment of the present invention, by collecting multiple vibration signals of different parts of the fixture, the state score of each vibration signal is obtained according to the fluctuation characteristics of each group of vibration signal sequences and the difference between the vibration signals between the vibration signal sequences, and the overall state score of the fixture at the current sampling moment is obtained by weighted fusion of the state scores of various vibration signals at the current sampling moment, which not only realizes the comprehensive monitoring of the fixture, but also makes the judgment of the operation state of the fixture at the current sampling moment more accurate, realizing more comprehensive, intuitive and accurate monitoring of the fixture.
[0087] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.
Claims
1. A real-time monitoring system for the operation status of a fixture based on the Internet of Things, 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, the following method is implemented: During the operation of the fixture, at least two vibration signal sequences of each part to be detected at the current sampling time are collected to obtain all vibration signal sequences of a preset number of parts to be detected; For any group of vibration signal sequences, a vibration signal at a current sampling moment is obtained from the any group of vibration signal sequences and recorded as a target signal; an abnormal value of the target signal is obtained according to the fluctuation characteristics of the any group of vibration signal sequences; and a state consistency index of the target signal is obtained according to the vibration signal type of the any group of vibration signal sequences and the difference in vibration signals between each part to be detected and the vibration signal sequence of the same vibration signal type as the any group of vibration signal sequences at the current sampling moment; the vibration signal types include: vibration displacement signal, vibration velocity signal and vibration acceleration signal; According to the abnormal value and state consistency index of the target signal, the state score of the target signal is obtained, and according to the fluctuation characteristics of the arbitrary group of vibration signal sequences, the fusion weight of the target signal is obtained; The state score and fusion weight of the target signal in each group of vibration signal sequences are obtained, and the overall state score of the fixture at the current sampling moment is obtained based on the state score and fusion weight of the target signal in each group of vibration signal sequences. The operating state of the fixture at the current sampling moment is judged based on the overall state score of the fixture at the current sampling moment.
2. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 1 is characterized in that: The obtaining, according to the fluctuation characteristics of the arbitrary group of vibration signal sequences, the abnormal value of the target signal comprises: Obtaining a vibration period of the arbitrary group of vibration signal sequences, and dividing the arbitrary group of vibration signal sequences into at least two subsequences according to the vibration period; Obtain the number of extreme value points of each subsequence in the arbitrary group of vibration signal sequences, and obtain the first absolute value of the difference between the number of extreme value points of the subsequence where the target signal is located and the number of extreme value points of the first subsequence; Obtaining the position number of the target signal in the subsequence where the target signal is located, and combining the amplitudes of the vibration signals having the same position number as the target signal in each subsequence into a first target sequence; Obtaining a first quartile and a third quartile in the first target sequence, calculating a first mean of the first quartile and the third quartile, obtaining a first difference between the amplitude of the target signal and the first mean, and obtaining a maximum value between the first difference and a constant 0; A sum of the first difference absolute value and the maximum value is obtained as an abnormal value of the target signal.
3. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 2 is characterized in that: The obtaining of the state consistency index of the target signal according to the vibration signal type of the arbitrary group of vibration signal sequences and the difference in vibration signals between each to-be-detected part and the vibration signal sequence of the same vibration signal type as the arbitrary group of vibration signal sequences at the current sampling moment comprises: The vibration signal types include: vibration displacement signal, vibration velocity signal and vibration acceleration signal; When the vibration signal type of any one group of vibration signal sequences is a vibration displacement signal, the connection point between the fixture and the workpiece is set as a reference position, the distance between the position of each part to be detected and the reference position is obtained to form a distance sequence, and in each group of vibration signal sequences with the same vibration signal type as the any one group of vibration signal sequences, the amplitude of the vibration signal at the current sampling moment is obtained to form an amplitude sequence, and the amplitude sequence and the distance sequence are inversely fitted to obtain a fitted inverse proportional function of amplitude and distance; Obtain a first distance between the position of the to-be-detected part where the target signal is located and the reference position, obtain a fitting amplitude of the first distance in the fitted inverse proportional function, calculate a second absolute value of a difference between the amplitude of the target signal and the fitting amplitude, and obtain the inverse of the absolute value of the second difference as a state consistency indicator of the target signal.
4. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 3 is characterized in that: The step of obtaining the state consistency index of the target signal according to the vibration signal type of the arbitrary group of vibration signal sequences and the difference in vibration signals between each vibration signal sequence of the to-be-detected part having the same vibration signal type as the arbitrary group of vibration signal sequences at the current sampling moment, further includes: When the vibration signal type of any one of the group of vibration signal sequences is a vibration velocity signal, the subsequence in which the target signal is located is recorded as a first target subsequence, the first target subsequence is divided into at least one sequence segment according to a preset length, the curvature of each sequence segment is calculated respectively, and a first curvature mean is obtained accordingly; Detecting whether the to-be-detected part where any one group of vibration signal sequences is located has a displacement change relative to the fixture; if the to-be-detected part where any one group of vibration signal sequences is located has not a displacement change relative to the fixture, obtaining the inverse of the first curvature mean as a state consistency indicator of the target signal; If the part to be detected where any one of the groups of vibration signal sequences is located produces a displacement change relative to the fixture, the first phase of the target signal is obtained, and in each group of vibration signal sequences with the same vibration signal type as the any one of the groups of vibration signal sequences, the phase of the vibration signal at the current sampling moment is obtained to form a second target sequence, and the phase with the highest frequency in the second target sequence is obtained. The absolute value of the third difference between the first phase of the target signal and the phase with the highest frequency in the second target sequence is calculated, and the third addition result of the third absolute value of the difference and the constant 1 is calculated. The average of the inverse of the third addition result and the inverse of the first curvature mean is obtained as the state consistency indicator of the target signal.
5. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 3 is characterized in that: The step of obtaining the state consistency index of the target signal according to the vibration signal type of the arbitrary group of vibration signal sequences and the difference in vibration signals between each vibration signal sequence of the to-be-detected part having the same vibration signal type as the arbitrary group of vibration signal sequences at the current sampling moment, further includes: When the vibration signal type of any one of the group of vibration signal sequences is a vibration acceleration signal, the subsequence where the target signal is located is recorded as a second target subsequence, the second target subsequence is divided into at least one sequence segment according to a preset length, and the curvature of each sequence segment is calculated respectively, so as to obtain a corresponding second curvature mean; Detecting whether the to-be-detected part where any one group of vibration signal sequences is located has a displacement change relative to the fixture; if the to-be-detected part where any one group of vibration signal sequences is located has not a displacement change relative to the fixture, obtaining the inverse of the second curvature mean as a state consistency indicator of the target signal; If the part to be detected where any one of the groups of vibration signal sequences is located produces a displacement change relative to the fixture, the second phase of the target signal is obtained, and in each group of vibration signal sequences with the same vibration signal type as the any one of the groups of vibration signal sequences, the phase composition of the vibration signal at the current sampling moment is obtained to form a third target sequence, and the phase with the highest frequency in the third target sequence is obtained. The fourth absolute value of the difference between the second phase of the target signal and the phase with the highest frequency in the third target sequence is calculated, and the fourth addition result of the fourth absolute value of the difference and the constant 1 is calculated. The average of the inverse of the fourth addition result and the inverse of the second curvature mean is obtained as the state consistency indicator of the target signal.
6. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 1 is characterized in that: The step of obtaining a state score of the target signal according to the abnormal value and the state consistency index of the target signal includes: Normalize the outlier value of the target signal to obtain a normalized outlier value, calculate the subtraction result of a constant 1 and the normalized outlier value, calculate the second mean of the subtraction result and the state consistency index of the target signal, and obtain the second mean of a preset multiple as the state score of the target signal.
7. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 2 is characterized in that: The obtaining the fusion weight of the target signal according to the fluctuation characteristics of the arbitrary group of vibration signal sequences includes: The maximum amplitude in the subsequence where the target signal is located is obtained, and the maximum amplitude in each subsequence at the current sampling moment in each group of vibration signal sequences is obtained and accumulated to obtain the corresponding accumulated value, and the ratio of the maximum amplitude in the subsequence where the target signal is located to the accumulated value is calculated as the fusion weight of the target signal.
8. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 1 is characterized in that: The step of obtaining the overall state score of the fixture at the current sampling moment according to the state score and fusion weight of the target signal in each group of vibration signal sequences includes: According to the fusion weight of the target signal in each group of vibration signal sequences, the state scores of the target signals in all vibration signal sequences are weighted and summed to obtain the overall state score of the fixture at the current sampling moment.
9. The real-time monitoring system for fixture operation status based on the Internet of Things according to claim 8 is characterized in that: The step of judging the operating state of the fixture at the current sampling moment according to the overall state score of the fixture at the current sampling moment includes: Setting an overall status score threshold interval, wherein the overall status score threshold interval includes a first abnormal interval, a second abnormal interval, a third abnormal interval and a normal interval, the overall status score of the first abnormal interval is less than the overall status score of the second abnormal interval, the overall status score of the second abnormal interval is less than the overall status score of the third abnormal interval, and the overall status score of the third abnormal interval is less than the overall status score of the normal interval; When the overall state score of the fixture at the current sampling moment is in the first abnormal interval, it is confirmed that the fixture is in a severely abnormal operating state; When the overall state score of the fixture at the current sampling moment is in the second abnormal interval, it is confirmed that the fixture is in a moderately abnormal operating state; When the overall state score of the clamp at the current sampling moment is in the third abnormal interval, it is confirmed that the clamp is in a slightly abnormal operation state; When the overall status score of the clamp at the current sampling moment is within the normal range, it is confirmed that the clamp is in a normal operating state.
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