CN110199233B

CN110199233B - State judging system

Info

Publication number: CN110199233B
Application number: CN201780084174.2A
Authority: CN
Inventors: 井谷一夫; 锦戸宪治
Original assignee: Anywire Corp
Current assignee: Anywire Corp
Priority date: 2017-01-27
Filing date: 2017-01-27
Publication date: 2022-07-22
Anticipated expiration: 2037-01-27
Also published as: KR20190102229A; JP6970694B2; WO2018138862A1; KR102340965B1; JPWO2018138862A1; CN110199233A

Abstract

The invention provides a state judging system, comprising an imaging mechanism which images the waveform generated along with the action of a state judging object; a reference image accumulation unit that accumulates a plurality of images of the waveform in the reference state as a reference image; a comparison means for comparing the inspection image data with the reference image data using the waveform image obtained when the state judgment is performed as an inspection image, and classifying a difference between the inspection image data and the reference image data; and a judging means for judging that the difference is a non-significant difference as a reference state and that the difference is a significant difference as a non-reference state based on the level calculated by the comparing means. Since the reference image data and the inspection image data are compared, it is possible to perform the judgment by the arithmetic processing without the need of a person having a skill enough to perform the judgment.

Description

State judging system

Technical Field

The present invention relates to a state determination system for determining whether a state determination target is in a predetermined state (normal state) or a state deviated from the predetermined state (abnormal state).

Background

When a large number of devices are installed and used in a wide area such as a factory, the devices are generally centrally managed on the control side of a management center or the like that collects various information indicating the operation state.

In such a case, as data collected on the control side, for example, in the case of an electric machine, information on voltage and current is collected and collected on the control side, and in the case of a device (pump, compressor, etc.) that operates a fluid, information on flow rate and temperature is collected and collected on the control side. Subsequently, the control-side arithmetic processing unit determines whether or not a predetermined state is maintained through comparison processing of a threshold value or the like.

However, even if the information indicating the operating state of the device or equipment is processed by a known algorithm, it is not easy to determine whether or not the information is maintained in a predetermined state according to the result obtained from the information. For example, as with a signal waveform obtained by an analog oscilloscope or a digital oscilloscope, a waveform generated in accordance with the operation of a state determination target is useful information for determining the state of the determination target, but includes many determination factors, and it is difficult to make an accurate determination by an arithmetic processing of simply comparing with a threshold value. Therefore, in practice, the judgment using the state of the waveform depends on the skill of a skilled judgment person.

On the other hand, the judgment of the skill of the judge cannot be performed even if there is no person having sufficient skill for the judgment at a place where the waveform can be confirmed. Therefore, a method has been proposed which can perform state determination even in a case where a person having sufficient skill for determination does not exist at a place where a waveform can be confirmed. For example, japanese patent laid-open No. 2003-256028 proposes a remote monitoring system capable of easily observing each signal waveform of a surface inspection machine from a remote place by a terminal computer and quickly performing failure analysis and the like by an expert (a person having sufficient skills to judge).

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent laid-open publication No. 2003-256028

Disclosure of Invention

[ problems to be solved by the invention ]

However, even if the waveform can be confirmed at a remote place, a person having sufficient skill in judgment continues to maintain the waveform and monitoring the waveform may be difficult. Therefore, the conventional state determination method in which the state determination is performed by the skill of the determiner using the waveform is difficult to be applied to a case where there is a possibility that a normal state suddenly becomes an abnormal state or a case where a normal state (predetermined state) and an abnormal state (state deviated from the predetermined state) are repeatedly changed.

Accordingly, an object of the present invention is to provide a state determination system that enables continuous monitoring of a state determination target using a waveform generated in accordance with an operation of the state determination target.

[ means for solving the problems ]

The state determination system according to the present invention includes the following means: an imaging means for imaging a waveform generated in accordance with an operation of a state determination target; a reference image accumulation unit configured to accumulate a plurality of images of the waveform in a reference state as a reference image; a comparison means for comparing data of the inspection image with data of the plurality of reference images by using the image of the waveform obtained when the state determination is performed as an inspection image, and classifying a difference between the data of the inspection image and the data of the reference images; and a determination unit configured to determine that the difference is in the non-significant state as a reference state and that the difference is in the significant state as a non-reference state, based on the level calculated by the comparison unit.

In the present invention, the difference is meaningful and means that the difference exceeds the allowable range. For example, when the state quantity available in the normal range of the device to be monitored has a large value, the difference in data can be tolerated if the difference falls within such a large range, and it is determined that there is no significant difference and the two data match. On the other hand, when the difference between the data exceeds the range of the magnitude of the state quantity available in the normal state, it is determined that there is a significant difference and the two data are not matched.

The waveform may also include a temporal change in a physical quantity that changes in accordance with the motion of the driving portion having the state determination target. The physical quantities that change in accordance with the movement of the driving portion include, for example, vibration, pressure, sound, acceleration, tension, heat, flow rate, light amount, deformation amount, and ozone amount.

The waveform may also include a temporal change in current or voltage in the power supply to the state determination target.

The waveform may also include a waveform of a signal received or transmitted by the state determination object.

The imaging of the waveforms may also be performed for a plurality of types of waveforms having different properties.

The reference image and the inspection image may be composed of data obtained by extracting the waveform data for a predetermined period.

The grade may also be written to the inspection image and delivered to the determination mechanism.

The judging means may judge the presence or absence of an abnormal state based on the judgment as to whether or not the abnormal state is the reference state, and judge the service life of the state judgment object when the cumulative number of the number of occurrences of the data in the abnormal state reaches a predetermined value or when the frequency of the number of occurrences reaches a predetermined value. [ efficacy against the prior art ]

In the present invention, in the reference state to be state-judged, the comparison between the data of the reference image in which the waveform generated in association with the motion to be state-judged is imaged and the data of the inspection image in which the waveform generated in association with the motion to be state-judged is imaged when the state judgment is performed makes it possible to judge the state by the arithmetic processing without the need for a person having sufficient skill for the judgment.

Further, since the difference between the data of the inspection image and the data of the reference image is classified into the levels, and the reference state is determined when the difference is not significant based on the levels, and the non-reference state is determined when the difference is significant, it is possible to perform more accurate determination than the past operation process that simply compares the difference with the threshold value.

Further, the images of the plurality of waveforms in the reference state of the state determination target are taken as the reference images, so that the accuracy of determination can be improved.

Therefore, according to the present invention, it is possible to perform state determination by arithmetic processing using a waveform generated in accordance with an operation of a state determination target, and to continuously monitor the state determination target.

Drawings

Fig. 1 is a configuration diagram of a state determination system relating to the present invention.

Fig. 2 is a functional block diagram of a sensor controller.

FIG. 3 is a functional block diagram of a storage server and a search engine server.

Detailed Description

The following description relates to embodiments of the device-machine anomaly detection system of the present invention.

This system for detecting abnormality of a device or equipment is a system for remotely detecting abnormality of a rotating device such as a plurality of motors in a factory where the rotating device is installed, with the rotating device being a state determination object 10. In this embodiment, the plurality of state determination targets 10 are collectively controlled by the PLC5 connected to the communication line 9, but may be controlled by a dedicated controller.

The state determining object 10 is provided with a sensor 1 for detecting vibration as a state quantity that changes by an operation. In this embodiment, as the sensor 1, a pair of shaft vibration sensors is used. One sensor (first sensor 1a) of the paired sensors 1a and 1b is provided in a direction in which a vertical component of the axial vibration of the state determination object 10 is detected, and the other sensor (second sensor 1b) is provided in a direction in which a horizontal component of the axial vibration is detected.

The sensor 1 is not limited as long as it is necessary to form an image of a waveform generated in accordance with the operation of the state determination object 10 and can detect a state quantity that changes in accordance with the operation state of the state determination object 10. Pressure sensors, acceleration sensors, rotational speed sensors, sound sensors, torque sensors, load current sensors, etc. may be used. Further, the two or more may be used alone or in pairs, or a plurality of them may be used as a set. In the case of using a plurality of the compounds as a pair or a group, the compounds may be different in kind. For example, as the combination of the first sensor 1a and the second sensor 1b, a combination of a pressure sensor and a vibration sensor, or a combination of an acceleration sensor and a sound sensor may be used.

The sensor 1 is connected to the sensor controller 2. The sensor controller 2 is connected to the search engine server 3 and the storage server 4 via a communication line 9. The search engine server 3 corresponds to a determination means of the present invention, and data of the vibration obtained by the sensor 1 is converted into signal waveform image data in the sensor controller 2, and is transmitted to the search engine server 3 via the communication line 9 to be subjected to determination processing described later.

< sensing controller >

As shown in fig. 2, the sensor controller 2 includes a first data conversion unit 21a, a second data conversion unit 21b, an image data transfer unit 22, a communication unit 23, a storage unit 24, a mode determination unit 25, and a reference image forming switch 26.

The first data conversion unit 21a constitutes the imaging unit of the present invention together with the first sensor 1a, converts the vibration data obtained via the first sensor 1a into image data (sensor signal waveform image data) representing a waveform of temporal change in amplitude, extracts data in one frame period (hereinafter referred to as "frame image data"), and delivers the data to the image data transmission unit 22. Similarly, the second data conversion mechanism 21b and the second sensor 1b together constitute the imaging mechanism of the present invention, converts the vibration data obtained via the second sensor 1b into sensor signal waveform image data, and delivers the frame image data to the image data transfer mechanism 22. The one frame period corresponds to a predetermined period of the present invention, but can be set as appropriate in accordance with the object to be measured or the measurement conditions.

The image data transfer means 22 performs the following processing in accordance with the mode data output from the mode determination means 25. First, when the mode data indicates the on-line mode, the frame image data delivered by the first data conversion unit 21a is given to the machine number given to the sensor controller 2 and the sensor number including the sensor type data given by the first sensor 1a, and delivered to the communication unit 23. The frame image data delivered by the second data master exchange means 21b is given to the machine number given to the sensor controller 2 and the sensor number including the sensor type data given by the second sensor 1b, and delivered to the communication means 23.

In the on-line mode, the waveform image composed of the frame image data delivered to the communication means 23 is an inspection image corresponding to the present invention.

On the other hand, when the mode data indicates the reference image generation mode, one or both of the frame image data delivered by the first data conversion mechanism 21a or the second data conversion mechanism 21b is given to an identifier indicating a reference image and delivered to the communication mechanism 23.

The reference image may be a reference for determining the presence or absence of an abnormality of the state determination object 10, and may be data obtained when a failed device is operated in the same model as the state determination object 10, or data obtained when the state determination object 10 is operated normally, for example.

The communication means 23 transmits the data delivered by the image data transmission means 22 to the search engine server 3 and the storage server 4 via the communication line 9. When the state determination object 10 is determined to be in an abnormal state by the state determination described later and the abnormal state data transmitted from the determination device 6 is received, the abnormal state data is delivered to the storage means 24.

The storage means 24 stores the machine number given by the sensor controller 2, the sensor number including the sensor type data given by the first sensor 1a and the second sensor 1b, and even the reference image number applied to the state determination target 10, and delivers this to the image data transmission means 22. In addition, when the abnormal state data is delivered from the communication means 23, this data is also stored.

The machine number stored in the storage means 24, the sensor number including the sensor type data, and the reference image number may be input by any known method suitable for the shape and installation state of the sensor controller 2. For example, the setting may be made by using another terminal device that transmits and receives data to and from the sensor controller 2 in a non-contact manner.

The mode determination mechanism 25 outputs mode data in accordance with the mode selected by the operation of the reference image forming switch 26 to the image data transmission mechanism 22. In this embodiment, the reference image forming switch 26 is normally OFF, and the reference image forming mode is selected by switching to the ON state. When base image forming switch 26 is turned ON, the mode data indicating the reference image forming mode is output to image data transmission mechanism 22. On the other hand, the mode data showing the on-line mode is output to the image transfer mechanism 22 at ordinary times (in a state where the reference image forming switch 26 is OFF).

< search engine Server >

As shown in fig. 3, the search engine server 3 includes a communication unit 31 and a matching unit 32.

The communication means 31 delivers the data transmitted by the sensor controller 2 to the collation means 32. In addition, data matching the request of the comparison means 32 is acquired from the storage server 4 via the communication line 9 and delivered to the comparison means 32. Further, the frame image data delivered from the collation unit 32 and written with the numerical value of the similarity described later is delivered to the judgment device 6 via the communication line 9.

The comparison means 32 compares the inspection image data with the reference image data. First, one image number is determined from a plurality of reference images based on the device number data included in the data delivered by the communication means 31, the sensor number data including the sensor type data, and the reference image number. Next, the data acquisition request of the reference image is output to the communication means 31. Further, the frame image data included in the data delivered by the communication means 31 is temporarily stored as the inspection image data until the end of the comparison processing.

The communication means 31 that has received the data acquisition request acquires data matching the request, that is, reference image data, from the storage server 4 via the communication line 9 as described above, and delivers the data to the collating means 32.

The matching means 32 that has received the delivery of the data of the reference image from the communication means 31 uses the frame image data included in the data delivered by the communication means 31 as the inspection image data, and performs matching between the inspection image data and the data of the reference image based on each method.

The comparison of the images can be performed by comparing style elements, features, and the like extracted from the image data between the two methods. In addition, the image data has parameters such as position and direction, and the arrangement in the parameter space is compared as a pattern in the comparison of the images.

In this embodiment, template matching is used as the image comparison method. The reference image data is referred to as a template of the state determination target 10.

In the template matching method, portions similar to the reference image data in the inspection image data are detected one by one. Specifically, the similarity (or the degree of difference) of the overlapping region is calculated while sequentially shifting the reference image data on the inspection image data. The smaller the calculated value of the similarity is, the similar images are at the portions where the reference image data of the template overlap. In the case of perfect agreement, the calculation result value is 0, and the smaller value closer to 0 is more similar.

When the calculated numerical value becomes smaller than or equal to a certain degree or more in the case of the similarity at an arbitrary position of the inspection image data, the position is specified as a detected position.

In this embodiment, although the cross correlation method is used as the method for calculating the similarity, the detailed calculation formula and the like will not be described because the method is a known method.

The predetermined similarity value obtained as the calculation result value is processed and written into a specific position in the frame image data stored as the inspection image. Next, the data acquisition request of the next reference image is output to the communication means 31.

In addition, in this embodiment, although the numerical value of the similarity itself is used as the level, the level may be defined by a predetermined numerical range.

The matching means 32 that has received the delivery of the data of the next reference image from the communication means 31 repeats the above-described matching until the matching process for all of the plurality of reference images is completed. After the matching process for all the reference images is completed, the frame image data in which the numerical values of the similarity degrees of the plurality of reference images are written is delivered to the determination device 6 via the communication means 31.

In addition to the pattern matching described above, the image matching method may also include DP matching which is a one-dimensional elastic matching technique, or may compare pattern matching between feature sets by creating patterns in which features are vertexes and relationships between features are sides and performing additional correspondence between patterns. These methods may be used according to the use situation.

In the determination device 6 that has received the delivery of the frame image data in which the numerical values of the similarity degrees of the plurality of reference images are written, the determination means 61 provided therein determines the state of the state determination object 10 based on the numerical values of the similarity degrees.

The determination unit 61 first determines that the difference between the inspection image and the reference image is significant when the similarity written in the frame image data includes one greater than or equal to a predetermined threshold. When all the similarities are equal to or less than the threshold, it is determined that the difference between the inspection image and the reference image is meaningless.

The determination of whether the image is in an abnormal state is based on the properties of the reference image. For example, when data of a failure state of the device to be the state determination object 10 can be acquired, a waveform image obtained in the failure state can be used as a reference image, and in this case, a determination that a difference between the inspection image and the reference image is meaningless and is used as a reference state means an abnormal state of the state determination object 10.

On the other hand, when data of a failure state of the device to be the state determination target 10 cannot be acquired, a waveform image obtained in a normal state can be used as a reference image, and in this case, a judgment that a difference between the inspection image and the reference image is significant and is a non-reference state means an abnormal state of the state determination target 10.

In addition, when data of a failure state can be acquired, it is also possible to perform determination using both the waveform image of the failure state and the waveform image of the normal state. For example, when the normal state is set as the first reference state, the normal state waveform image is set as the first reference image, the failure state is set as the second state, and the failure state waveform image is set as the second reference image, and the first reference image is compared with the first reference image to determine that the first reference image is not the first reference state, the second reference image is compared with the normal state waveform image. When the state is determined as the second reference state, it may be determined as an abnormal state.

The determination means 61 determines the presence or absence of an abnormal state of the state determination target 10 based on the determination of whether or not the state determination target 10 is in the reference state based on these references. Next, when the determination means 61 determines that the state is abnormal, the determination device 6 outputs the frame image data in which the numerical value of the similarity is written as abnormal state data to the sensor controller 2 and the storage server 4 of the state determination object 10 via the communication line 9.

As shown in fig. 3, the storage server 4 includes a communication unit 41 and a storage unit 42.

The communication means 41 receives the data of the reference image transmitted from the sensor controller 2 and delivers the data to the storage means 42. In response to a request from the search engine server 3, data of the base image is extracted from the data stored in the storage unit 42 and transmitted to the search engine server 3 via the communication line 9. Further, the abnormal state data transmitted from the judgment device 6 is received and delivered to the storage means 42.

The storage means 42 stores the data of the reference image and the abnormal state data delivered by the communication means 41.

The data accumulated in the storage unit 42 can be browsed by the determination device 6. In this case, the communication means 41 which has received the browsing request transmitted from the judgment device 6 extracts the data which meets the request from the data stored in the storage means 42, and delivers the data to the judgment device 6 via the communication line 9.

In this embodiment, although the search engine server 3 and the storage server 4 are separate entities, they can also be used as the integrated server 30 as shown by the phantom lines in fig. 1 and 3.

The determination device 6 is not limited to any other means as long as it includes an arithmetic processing unit capable of determining the presence or absence of the above-described abnormal state, and a known arithmetic processing unit can be used. In addition, more detailed determination regarding the abnormal state may be performed according to the performance of the arithmetic processing.

For example, the service life of the state determination target 10 may be determined by determining the presence or absence of the abnormal state as described above. The state judgment object 10 may also judge that the service life of the state judgment object 10 is the service life of the abnormal state data when the accumulated number of the occurrence number of the abnormal state data reaches a predetermined value or when the frequency of the occurrence number reaches a predetermined value, so as to prompt an alarm.

In the above-described embodiment, the shaft vibration is used as a condition for determining the presence or absence of an abnormal state, but a plurality of points may be used for determining the presence or absence of an abnormal state. For example, the pressure, voltage, sound, temperature, etc. may be used as the determination conditions. A combination of parameters may be predetermined.

Further, a related one of the plurality of state determination objects 10 may be selected in advance, and the presence or absence of an abnormal state may be determined based on information related to the plurality of state determination objects 10.

In the above-described embodiment, the waveform generated in accordance with the operation of the state determination target 10 is a time-varying change in the physical quantity (time-varying change in the axial vibration) that varies in accordance with the operation of the driving portion of the state determination target 10, but when the state determination target is a device having a communication function, a waveform of a signal received or transmitted by the state determination target may be used.

When a transmission signal transmitted and received by a state determination target is affected by noise or is attenuated, data cannot be transmitted and received as intended. When the normal state is set to a case where transmission and reception of data are performed as intended, the signal waveform is different between a case where the signal waveform is affected by noise and a case where the signal waveform is attenuated from the signal waveform in the normal state. Thus, it is possible to determine whether or not the signal is in a normal state by the difference in the signal waveform.

Description of the symbols

1 sensor

1a first sensor

1b second sensor

2 sensing controller

3 search engine server

4 storage server

5 PLC

6 judging device

9 communication line

10 status determination target

21a first data conversion mechanism

21b second data conversion mechanism

22 image data transfer mechanism

23, 31,41 communication mechanism

24, 42 storage mechanism

25 mode judging mechanism

26 reference image forming switch

30 integrated server

32 comparison mechanism

61 judging mechanism

Claims

1. A state determination system comprising the following mechanisms:

an imaging means for imaging a waveform generated in association with an operation of a state determination target;

a reference image accumulation unit configured to accumulate a plurality of images of the waveform in a reference state as a reference image;

a comparison means for comparing data of the inspection image with data of the plurality of reference images by using, as an inspection image, an image of the waveform obtained by measuring a state quantity that changes depending on an operation state of the state determination object when the state determination is performed, and classifying a difference between the data of the inspection image and the data of the reference images into a class; and

and a judging unit that judges that the difference is a non-significant difference as a reference state and that the difference is a significant difference as a non-reference state based on the level calculated by the comparing unit.

2. The state determination system according to claim 1, wherein the waveform includes a temporal change in a physical quantity that changes in accordance with an action of a driving portion having the state determination target.

3. The state determination system according to claim 1 or 2, wherein the waveform includes a temporal change in current or voltage in power supply to the state determination target.

4. A state determination system according to claim 1 or 2, wherein said waveform comprises a waveform of a signal received or transmitted by said state determination object.

5. A state judging system according to claim 1 or 2, wherein imaging of the waveform is performed for a plurality of kinds of waveforms different in property.

6. The state judging system according to claim 1 or 2, wherein the reference image and the inspection image are constituted by data obtained by extracting data of the waveform for a predetermined period.

7. The state judging system according to claim 1 or 2, wherein the grade is written to the inspection image and delivered to the judging mechanism.

8. The state determination system according to claim 1 or 2, wherein the determination means determines the presence or absence of an abnormal state based on the determination as to whether or not the reference state is present, and determines the service life of the state determination target when an accumulated number of occurrences of the data in the abnormal state reaches a predetermined numerical value or when a frequency of the number of occurrences reaches a predetermined numerical value.