JP7780262B2 - Monitoring system and monitoring method - Google Patents

Description

This disclosure relates to a monitoring system and a monitoring method.

Conventionally, a technology has been known in which a vibration power generation device including a vibration power generation element is attached to an object and the movement of the object is monitored.

Patent Document 1 discloses a system that manages the lock's open/closed status. It generates electricity from the vibrations that occur when a key is inserted into a lock and turned, and determines whether the lock is open or closed based on the voltage change. The electricity generated by the vibration generator is used to transmit data.

Patent Document 2 discloses an anomaly detection system for railway bridges, which attaches vibration power generation elements to the bearings and detects abnormalities by identifying vibrations that occur during abnormalities. In particular, the system sets the resonant frequency of the vibration power generation element to the frequency that occurs during abnormalities, and determines that an abnormality exists when the amount of power generated increases. It also discloses that multiple vibration power generation elements are attached to the bearings, and the location of an abnormality is identified by comparing the power generation status of each element.

JP 2019-218734 A International Publication No. 2016/194375

Manufacturing companies and other production plants are required to monitor the operating status of production equipment in order to ensure efficient production. This requires a variety of sensors, but installing sensors on existing equipment later can often be difficult, making wiring difficult. Furthermore, selecting sensors can be difficult without a certain level of knowledge and experience.

This disclosure was made in consideration of these problems, and aims to provide a monitoring system and monitoring method for monitoring the behavior of a monitored object.

A monitoring system according to one aspect of the present invention comprises a vibration power generation means for generating electricity in response to vibrations caused by the behavior of a monitored object, a detection means for detecting a predetermined voltage of a capacitor charged by the generated electricity, and an identification means for identifying the behavior of the monitored object corresponding to a predetermined charge/discharge pattern when the predetermined charge/discharge pattern appears in the charge/discharge pattern of the capacitor.

Furthermore, a monitoring method according to one aspect of the present invention includes an acquisition step of acquiring a charge/discharge pattern of a capacitor that is charged in response to vibrations caused by the operation of a monitored object, and an identification step of, when a predetermined charge/discharge pattern appears in the charge/discharge pattern of the capacitor, identifying the operation of the monitored object that corresponds to the predetermined charge/discharge pattern.

This disclosure provides a monitoring system and monitoring method for monitoring the behavior of a monitored object.

FIG. 1 is a diagram illustrating an overview of a monitoring system according to an embodiment. 1 is a block diagram illustrating an example of the configuration of a monitoring device according to an embodiment. FIG. 10 is a block diagram illustrating another example of the configuration of a monitoring device according to an embodiment. FIG. 10 is a diagram showing measurement results of the vibration frequency and capacitor voltage of a vibration power generation device according to an embodiment. FIG. 10 is a diagram showing measurement results of the vibration frequency and capacitor voltage of a vibration power generation device according to an embodiment. FIG. 10 is a diagram showing measurement results of the vibration frequency and capacitor voltage of a vibration power generation device according to an embodiment. FIG. 10 is a diagram showing measurement results of the vibration frequency and capacitor voltage of a vibration power generation device according to an embodiment. FIG. 10 is a diagram showing measurement results of the vibration frequency and capacitor voltage of a vibration power generation device according to an embodiment. 1 is a flowchart of a monitoring method according to one embodiment.

Embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The same elements will be designated by the same reference numerals throughout this specification and the accompanying drawings, and duplicate descriptions will be omitted.

(System Overview)
1 is a diagram illustrating an overview of a monitoring system according to an embodiment of the present invention, in which the monitoring system is applied to production facilities in a factory.

The monitoring system 100 includes a monitoring device 101 equipped with a vibration power generation device, and an information processing device 102. In this embodiment, the production facility 103 is monitored. In the production facility 103, material supplied from a material tank 110 is discharged into an oven 112 via a discharge device 111 and molded. A vacuum pump 113, a stirring motor 114, and a temperature regulator 115 are connected to the material tank 110. The temperature regulator 115 operates using thermal oil. The discharge device 111 also has a cylinder, which operates when pressure is applied by a hydraulic unit 116. Material can be loaded and unloaded from the oven 112 by opening and closing a door 117 (also referred to as an oven door). In this embodiment, for example, the monitoring device 101 is attached to the hydraulic unit 116, and the vibration power generation device included in the monitoring device 101 generates electricity using vibrations generated within the production facility 103. The vibration power generation device is not limited to the hydraulic unit 116, and can generate electricity from vibrations generated in various devices within the production facility 103, such as the material tank 110, discharge device 111, oven 112, vacuum pump 113, stirring motor 114, temperature regulator 115, and door 117 of the oven 112. Furthermore, the monitoring device 101 is not limited to being attached to the hydraulic unit 116, and may be attached to other devices within the production facility 103. The control panel 120 monitors the status of the production facility 103 and performs various controls.

Figure 2 is a block diagram showing an example configuration of a monitoring device according to one embodiment.

The monitoring device 101 includes a vibration power generation device 200 including a vibration power generation element 201, a charging circuit 202, and a capacitor 203, a voltage detection circuit 204, and a wireless module 205.

The vibration power generation element 201 generates power using ambient sound or vibration. The vibration power generation element 201, for example, includes a fixed electrode and a movable electrode, and generates power when the movable electrode vibrates relative to the fixed electrode due to the sound or vibration of the monitored object. The vibration power generation element 201 is set to maximize the amount of power generated in accordance with the dominant frequency of the monitored object, and is configured to generate greater power at specific frequencies. The dominant frequency refers to the frequency at which the system generates its maximum amplitude due to input acceleration, etc., and here refers to the frequency at which the system generates its maximum amplitude. For example, the vibration power generation element 201 can accommodate a variety of frequencies by adjusting the beam and movable weight. The vibration power generation element 201 may be an electret power generation element, a piezoelectric power generation element, an electromagnetic induction type, or a magnetostrictive type power generation element.

The charging circuit 202 converts the AC voltage output from the vibration power generation element 201 into DC voltage using a diode, and charges the capacitor 203. A resistor is connected in parallel to the capacitor 203, so that when power generation by the vibration power generation element 201 stops, the charging voltage drops due to the resistor (i.e., the capacitor is discharged). The resistance value of the resistor and the capacitance of the capacitor 203 are set taking into account the duration of vibration, the amount of power generation, etc.

The voltage detection circuit 204 detects the charging voltage of the capacitor 203. The voltage detection circuit 204 is configured to detect a predetermined voltage of the capacitor 203, and when it detects the predetermined voltage, it outputs the detection information to the wireless module 205.

The wireless module 205 converts the detection information detected by the voltage detection circuit 204 into a digital signal (A/D conversion) and transmits it to the information processing device 102 via wireless communication. Note that if the A/D conversion is performed by the voltage detection circuit 204 and the detection information is converted into a digital signal, the wireless module 205 does not need to perform the A/D conversion. (In other words, the voltage detection circuit 204 may perform the A/D conversion and then perform voltage detection processing on the digitally converted information.)

Based on the detection information received from the wireless module 205, the information processing device 102 matches the charge/discharge pattern of the capacitor 203 with pre-stored predetermined charge/discharge patterns. If the predetermined charge/discharge pattern appears in the charge/discharge pattern of the capacitor 203, the information processing device 102 identifies the behavior of the monitored object corresponding to the predetermined charge/discharge pattern. The charge/discharge pattern indicates voltage changes over time. The predetermined charge/discharge pattern includes various charge/discharge patterns corresponding to each of multiple behaviors of the monitored object, and by identifying the charge/discharge pattern occurring in the capacitor 203, the behavior of the monitored object can be identified. The predetermined charge/discharge pattern also includes charge/discharge patterns that arise from a combination of multiple behaviors of the monitored object. Once the information processing device 102 identifies the behavior of the monitored object, it notifies the identified behavior of the monitored object. The information processing device 102 may display the identified behavior on a display device, notify a predetermined notification destination, or transmit a predetermined signal.

The monitoring device 101 in the example of Figure 2 extracts the necessary information using the voltage detection circuit 204 and transmits the extracted information via the wireless module 205, making it suitable for power-saving operation of the monitoring device 101.

Figure 3 is a block diagram showing another example configuration of a monitoring device according to one embodiment.

The monitoring device 101 in FIG. 3 includes a vibration power generation device 200 including a vibration power generation element 201, a charging circuit 202, and a capacitor 203, a wireless module 205, and a power supply 207. Compared to the monitoring device 101 in FIG. 2, the monitoring device 101 in FIG. 3 does not include a voltage detection circuit 204, and the information processing device 102 includes a voltage detection circuit.

In the monitoring device 101 of Figure 3, the voltage detection process for the capacitor 203 is not performed. Instead, the wireless module 205 acquires raw information regarding the voltage of the capacitor 203, A/D converts the analog raw information into a digital signal, and transmits it to the information processing device 102 (i.e., the voltage detection circuit) as needed. The power supply 207 supplies power to drive the wireless module 205. In the monitoring device 101 of Figure 3, the power supply 207 is provided because the power consumption of the wireless module 205 is large.

The information processing device 102 in Figure 3 uses a voltage detection circuit to detect a predetermined voltage, and can also perform complex data processing (e.g., filtering, generating charge/discharge patterns, etc.) on received raw information. Furthermore, the wireless module 205 in Figure 3 A/D converts the raw information and transmits it as needed, resulting in greater power consumption than the monitoring device 101 in Figure 2. However, even with this configuration, it is possible to identify the operation of the monitored object using a predetermined charge/discharge pattern. While Figure 3 illustrates the information processing device 102 as being equipped with a voltage detection circuit, the process of detecting a predetermined voltage value from received information may be implemented by software. Software-based voltage detection processing can be achieved by a processor executing a program stored in the storage device of the information processing device 102.

<Demonstration experiment>
The following describes the results of a demonstration experiment in which the vibration power generation device 200 was actually attached to the hydraulic unit 116 of the production facility 103.

In this demonstration experiment, it was confirmed that the vibration power generation device 200 attached to the hydraulic unit 116 of the production equipment 103 can generate electricity up to a predetermined capacitor voltage of the capacitor 203 by operations such as opening and closing the oven door (door 117), operating the cylinder of the discharge device 111, and turning the power of the hydraulic unit 116 on and off.

In this demonstration experiment, the relationship between the amount of power generated by the vibration power generation device 200 and the capacitor voltage was confirmed. When the vibration power generation device 200 was generating sufficient power and in a stable state, the capacitor voltage of the vibration power generation device 200 was constant at 3.3 V. On the other hand, when the vibration power generation device 200 was not generating sufficient power, the capacitor voltage of the vibration power generation device 200 was less than 3.3 V.

The vibration power generation device 200 was set to have a resonant frequency of around 230 Hz, and was configured to maximize power generation at an acceleration of approximately 0.15 G.

First, we will briefly explain the results of this demonstration experiment on the above-mentioned operation.

(Opening and closing the oven door)
When the oven door closed, the capacitor voltage spiked to 3.3V.

(Cylinder operation of discharge device)
When the discharge device 111 performed a cylinder operation, a sudden rise and fall occurred in the capacitor voltage.

(hydraulic power supply)
When the power supply to the hydraulic unit 116 was turned from OFF to ON, the capacitor voltage suddenly rose from 0V to 3.3V.

(Oven door opening/closing, no cylinder operation of discharge device)
When the oven door was not opened or closed for a long period of time and the cylinder of the discharge device was not operating, the capacitor voltage sometimes dropped (this corresponds to Scope_15 and Scope_23 in Table 1 below).

Next, we will explain this demonstration experiment in more detail.

The vibration frequency and capacitor voltage of the vibration power generation device 200 were measured for each operating state shown in Table 1 below.

Figure 4 shows the measurement results of the vibration frequency and capacitor voltage of the vibration power generation device 200 when the oven door is opened and closed. As shown in the figure, the charge/discharge pattern of the capacitor voltage shows a drop when the oven door is closed, followed by a sudden rise. Scope_3 shown in Figure 4(a) and Scope_6 shown in Figure 4(b) both show data when there is no cylinder operation of the discharge device 111 and no power ON/OFF operation of the hydraulic unit 116. Note that the reason for the voltage rise between 25 s and 40 s in the graph shown in Figure 4(a) is unknown.

Figure 5 shows the measurement results of the vibration frequency and capacitor voltage of the vibration power generation device 200 when the oven door is opened and closed. As shown in the figure, the charge and discharge pattern of the capacitor voltage shows a drop when the oven door is closed, followed by a sudden rise. Scope_8 shown in Figure 5(a) shows data when there is no cylinder operation of the discharge device 111 and no power ON/OFF operation of the hydraulic unit 116. Scope_11 shown in Figure 5(b) shows data when there is cylinder operation of the discharge device 111 in addition to the opening and closing operation of the oven door, but there is no power ON/OFF operation of the hydraulic unit 116. In other words, Figure 5(b) shows the charge and discharge pattern that occurs due to a combination of multiple operations (opening and closing of the oven door and cylinder operation of the discharge device 111).

Figure 6 shows the measurement results of the vibration frequency and capacitor voltage of the vibration power generation device 200 related to the cylinder operation of the discharge device 111. As shown in the figure, the charge/discharge pattern of the capacitor voltage shows sudden rises and falls. Scope_3 shown in Figure 6(a) and Scope_11 shown in Figure 6(b) both show data when there is no opening/closing of the oven door and no power ON/OFF operation of the hydraulic unit 116.

Figure 7 shows the measurement results of the vibration frequency and capacitor voltage of the vibration power generation device 200 during the cylinder operation (continuous operation) of the discharge device 111. As shown in the figure, the charge/discharge pattern of the capacitor voltage shows continuous rapid increases and decreases. Scope_13 shown in Figures 7(a) and 7(b) shows data when there is no opening/closing of the oven door and no power ON/OFF operation of the hydraulic unit 116.

Figure 8 shows the measurement results of the vibration frequency and capacitor voltage of the vibration power generation device 200 when the power supply to the hydraulic unit 116 is turned from OFF to ON without the oven door opening or closing and the cylinder of the discharge device 111 operating. As shown in the figure, the charge and discharge pattern of the capacitor voltage shows a sudden rise from 0 V. The charge and discharge pattern of Scope_19 shown in Figure 8 is different and distinguishable from the charge and discharge patterns of Figures 4 and 5 in that the voltage rises in a shorter period of time. This is because the vibrations generated when the power supply to the hydraulic unit 116 is turned ON cause greater acceleration in the vibration power generation device 200 than the vibrations generated by opening and closing the oven door.

As explained above, this demonstration experiment confirmed that the vibration power generation device 200 attached to the hydraulic unit 116 of the production equipment 103 can generate electricity up to a predetermined capacitor voltage of the capacitor 203 through operations such as opening and closing the oven door (door 117), operating the cylinder of the discharge device 111, and turning the power of the hydraulic unit 116 on and off. It was also confirmed that the capacitor's charge and discharge patterns correspond to each operation.

In one embodiment of the present invention, the capacitor charge/discharge patterns described above are stored in advance in the information processing device 102 in association with the corresponding behavior of the monitored object. Then, when a specific charge/discharge pattern appears in the capacitor charge/discharge pattern caused by the behavior of the monitored object, the behavior of the monitored object corresponding to the specific charge/discharge pattern is identified. In this way, the behavior of the monitored object can be monitored.

Figure 9 shows a flowchart of a monitoring method according to one embodiment.

First, in step S901, the monitoring system 100 acquires the charge/discharge pattern of the capacitor 203, which is charged in response to vibrations caused by the operation of the production equipment 103 being monitored. That is, the voltage detection circuit 204 detects a predetermined voltage.

Next, in step S902, the monitoring system 100 determines whether a predetermined charge/discharge pattern appears in the capacitor charge/discharge pattern. That is, the information processing device 102 determines whether a predetermined charge/discharge pattern appears in the capacitor charge/discharge pattern based on the detection information of the voltage detection circuit 204. If the predetermined charge/discharge pattern appears, the process proceeds to step S903. On the other hand, if the predetermined charge/discharge pattern does not appear, the process returns to step S901 and repeats the process.

In step S903, the monitoring system 100 identifies an operation corresponding to a predetermined charging/discharging pattern. The monitoring system 100 notifies the identified operation.

In this way, the monitoring system 100, which includes the monitoring device 101 and the information processing device 102, can monitor the behavior of the monitored object.

The above-described embodiment provides the following advantages:

(1) Because the vibration-powered device in the monitoring device is used as a sensor, there is no need to supply power to the sensor. Furthermore, because multiple operations are related to the capacitor's charge/discharge patterns, it is possible to monitor multiple operations with a single vibration-powered device.

(2) Even when installing a monitoring device on an existing unit later, no wiring is required, making installation easy. Furthermore, since there is no need to select sensors, installation can be easily carried out even with limited knowledge or experience.

(3) By providing the monitoring device with a voltage detection circuit for the vibration-powered device, the amount of information transmitted by the wireless module can be reduced, enabling power-saving operation.

(4) On the other hand, by installing the voltage detection circuit in the information processing device rather than in the monitoring device, complex data processing such as filtering becomes possible.

100 Monitoring system 101 Monitoring device 102 Information processing device 200 Vibration power generation device 201 Vibration power generation element 202 Charging circuit 203 Capacitor 204 Voltage detection circuit 205 Wireless module

Claims (7)

a vibration power generation means for generating power in response to vibrations caused by the movement of the monitoring target;
a detection means for detecting a predetermined voltage of the capacitor charged by the power generation;
a specifying means for matching a charge/discharge pattern of the capacitor with a predetermined charge/discharge pattern stored in advance, and , when the predetermined charge/discharge pattern appears in the charge/discharge pattern of the capacitor, specifying a type of operation of the monitored object corresponding to the predetermined charge/discharge pattern;
A monitoring system characterized in that the predetermined charge/discharge pattern is a pattern of change in the voltage value of the capacitor over time, including charge/discharge patterns corresponding to each of multiple types of operations of the monitored object. The monitoring system described in claim 1, characterized in that the predetermined charge/discharge pattern includes a charge/discharge pattern that occurs due to a combination of multiple operations of the monitored object. The monitoring system described in claim 1 or 2, characterized in that the predetermined charge/discharge pattern is pre-stored in the identification means. The monitoring system described in any one of claims 1 to 3, further comprising a notification means for notifying the user of the identified behavior of the monitored object. The monitoring system described in any one of claims 1 to 4, further comprising a wireless communication means for transmitting information detected by the detection means to the identification means via wireless communication. The monitoring system described in any one of claims 1 to 4, further comprising a wireless transmission means for transmitting information regarding the capacitor voltage to the detection means via wireless communication. an acquisition step of acquiring a charge/discharge pattern of a capacitor charged in response to vibrations caused by the operation of the monitoring target;
a step of matching the charge/discharge pattern of the capacitor with a predetermined charge/discharge pattern stored in advance, and, when the predetermined charge/discharge pattern appears in the charge/discharge pattern of the capacitor, the predetermined charge/discharge pattern being a pattern of changes in the voltage value of the capacitor over time, the predetermined charge/discharge pattern including charge/discharge patterns corresponding to each of a plurality of types of operation of the monitored object, identifying the type of operation of the monitored object corresponding to the predetermined charge/discharge pattern.