Tire monitoring device, tire monitoring method, and tire monitoring program

Abstract

To assist investigation of a possible cause for internal pressure variation of a tire.SOLUTION: A tire monitoring device comprises: an acquisition unit that acquires internal pressure information indicating a transition in internal pressure of a tire; an estimation unit that, on the basis of a change pattern that is a pattern of internal pressure changes indicated by the internal pressure information, estimates at least one cause that causes the internal pressure changes; and an output unit that outputs cause information indicating the estimated cause.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The disclosed technology relates to a tire monitoring device, a tire monitoring method, and a tire monitoring program.

Background Art

[0002] As a technology for monitoring the state of tires provided on a vehicle, the following technologies are known. For example, Patent Document 1 describes a tire internal pressure warning system including an information terminal device that determines a malfunction situation such as a puncture or natural pressure reduction based on a change in the internal pressure of each tire received from an internal pressure acquisition device that acquires the internal pressure of each tire of a vehicle, and displays a warning according to the malfunction situation.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to maximize the performance of a tire, use at an appropriate internal pressure is required. On the other hand, due to the pressure difference between the inside and outside of the tire, it is common for the internal pressure of the tire to gradually decrease as the air inside the tire gradually leaks out. A TPMS (Tire Pressure Monitoring System) that issues an alarm when the internal pressure of the tire falls below a threshold value is known. When an alarm is issued from the TPMS, for example, it can be connected to a response such as refilling the air.

[0005] Currently, when an alarm is issued from the TPMS, maintenance is carried out on the target tire. However, if the target tire can be incorporated into the maintenance plan at a stage before the alarm is issued, it is considered that it will be easier to secure resources such as facilities, parts, and personnel. Also, according to the current response, for example, when an unexpected situation such as a rapid increase in the rate of decrease in internal pressure occurs, an emergency response is required, and in some cases, a significant modification of the original maintenance plan is necessary. In this case, there is a risk that it will be difficult to secure resources such as facilities, parts, and personnel.

[0006] In addition, existing TPMSs cannot estimate and notify the cause of the decrease in tire internal pressure. For this reason, for abnormalities that cannot be eliminated by simply refilling the air, the response is limited to simply refilling the air, and a case may occur where an abnormality is noticed while repeatedly refilling the air in response to frequently issued alarms. Until the abnormality is noticed, the tire will be used at an internal pressure outside the appropriate range. As a result, the durability of the tire decreases, and customer values such as safety and long-term use are damaged. Also, multiple causes are considered as the cause of the decrease in tire internal pressure. For this reason, at the maintenance site, it is necessary to conduct multiple inspections to investigate the cause, and the work at the site has become complicated.

[0007] In addition, since the time required for maintenance work varies greatly depending on the cause of the internal pressure decrease, it is difficult to predict the maintenance work time in a situation where the cause is unknown. If the work time is longer than planned, a modification to the original maintenance plan is necessary. On the other hand, if the work time is shorter than planned, losses such as available personnel occur.

[0008] Furthermore, among the parts that need to be replaced during maintenance work, there are those with high costs for acquisition and those that require time to obtain, and there are many cases where a relatively long lead time is required from the maintenance plan to its execution. In situations where the cause of the internal pressure drop is unknown, it is impossible to identify the parts to be replaced, and it becomes difficult to formulate a maintenance plan.

[0009] The disclosed technology has been made in view of the above points, and aims to assist in investigating the cause of the change in the internal pressure of the tire.

Means for Solving the Problem

[0010] The tire monitoring device according to the first aspect of the disclosed technology includes an acquisition unit that acquires internal pressure information indicating the transition of the internal pressure of the tire, an estimation unit that estimates at least one cause of the internal pressure change based on a change pattern that is a pattern of the internal pressure change indicated by the internal pressure information, and an output unit that outputs cause information indicating the estimated cause.

[0011] The tire monitoring device according to the second aspect of the disclosed technology is the tire monitoring device according to the first aspect, and further includes a detection unit that detects an abnormal internal pressure change based on the change pattern indicated by the internal pressure information, and the estimation unit estimates the cause for the tire in which the abnormal internal pressure change has been detected.

[0012] The tire monitoring device according to the third aspect of the disclosed technology is the tire monitoring device according to the first or second aspect, and the estimation unit estimates the cause based on the rate of change of the internal pressure indicated by the internal pressure information.

[0013] The tire monitoring device according to the fourth aspect of the disclosed technology is the tire monitoring device according to the first or second aspect, and the estimation unit estimates the cause by comparing a plurality of reference patterns corresponding to each of a plurality of causes of the internal pressure change with the change pattern.

[0014] The tire monitoring device according to the fifth aspect of the disclosed technology is the tire monitoring device according to the first or second aspect, wherein the estimation unit estimates the cause based on the change pattern before and after maintenance indicated by the internal pressure information.

[0015] The tire monitoring device according to the sixth aspect of the disclosed technology is the tire monitoring device according to the first or second aspect, wherein the estimation unit uses a classification model learned by machine learning, which takes the change pattern as an input and outputs the cause, to estimate the cause.

[0016] The tire monitoring device according to the seventh aspect of the disclosed technology is the tire monitoring device according to any one of the first to sixth aspects, wherein the output unit outputs the cause information to a predetermined device and / or uploads it to a website.

[0017] The tire monitoring device according to the eighth aspect of the disclosed technology is the tire monitoring device according to any one of the first to sixth aspects, wherein the acquisition unit acquires the internal pressure information for each of a plurality of tires provided on each of a plurality of vehicles, the estimation unit estimates the cause for each vehicle and each tire mounting position, and the output unit outputs the cause information for each vehicle and each tire mounting position.

[0018] The tire monitoring device according to the ninth aspect of the disclosed technology is the tire monitoring device according to the second aspect, wherein the acquisition unit acquires the internal pressure information for each of a plurality of tires provided on each of a plurality of vehicles, and the detection unit detects an abnormal internal pressure change by comparing the internal pressure information for each of the plurality of tires with each other.

[0019] The tire monitoring device according to the tenth aspect of the disclosed technology is the tire monitoring device according to any one of the first to ninth aspects, and further includes a specifying unit that specifies a countermeasure method for the cause estimated by the estimating unit, and the output unit outputs countermeasure information indicating the specified countermeasure method together with the cause information.

[0020] The tire monitoring method according to the eleventh aspect of the disclosed technology is a method in which a computer executes a process of acquiring internal pressure information indicating the transition of the internal pressure of a tire, estimating at least one cause that causes the internal pressure change based on a change pattern that is a pattern of the internal pressure change indicated by the internal pressure information, and outputting cause information indicating the estimated cause.

[0021] The tire monitoring program according to the twelfth aspect of the disclosed technology is a program for causing a computer to execute a process of acquiring internal pressure information indicating the transition of the internal pressure of a tire, estimating at least one cause that causes the internal pressure change based on a change pattern that is a pattern of the internal pressure change indicated by the internal pressure information, and outputting cause information indicating the estimated cause.

Advantages of the Invention

[0022] According to the disclosed technology, it becomes possible to assist in investigating the cause of the change in the internal pressure of the tire.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

Figure 7

Figure 8

Figure 9A

Figure 9B

Figure 10

Figure 11A

Figure 11B

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Embodiments for Carrying Out the Invention

[0024] Hereinafter, an example of an embodiment of the disclosed technology will be described with reference to the drawings. In each drawing, the same or equivalent components and parts are given the same reference numerals, and duplicate explanations are omitted.

[0025] [First Embodiment] FIG. 1 is a diagram showing an example of the configuration of a tire monitoring system 1 according to an embodiment of the disclosed technology. The tire monitoring system 1 is a system for individually monitoring each of a plurality of tires 41 mounted on a vehicle 40 to be monitored. The tire monitoring system 1 includes an internal pressure sensor 42, a communication device 30, a tire monitoring device 10, and a terminal device 20.

[0026] In FIG. 1, three vehicles 40 each equipped with six tires 41 are illustrated, but the number of vehicles to be monitored by the tire monitoring system 1 may be less than three or may be four or more. The number of tires 41 mounted on each vehicle 40 is not particularly limited. The type of the vehicle 40 may be, for example, a work vehicle such as a dump truck used at a mine or a construction site, but is not limited thereto. As another example, for instance, one passenger car, bus, small truck, etc. may be the monitoring target, and the number of tires to be mounted may also be in patterns of three or four.

[0027] The internal pressure sensor 42 is provided for each tire 41 of each vehicle 40. The internal pressure sensor 42 outputs a measured value of the internal pressure, which is the pressure of the air inside the corresponding tire 41. The output of the measured value of the internal pressure by the internal pressure sensor 42 may be performed at any time or intermittently. The intermittent output may be regular or irregular.

[0028] The communication device 30 is mounted on each of the plurality of vehicles 40. The communication device 30 aggregates the measured values of the internal pressure output from each of the internal pressure sensors 42 provided for each tire 41 of the corresponding vehicle 40, and transmits this to the tire monitoring device 10. That is, in the present embodiment, each of the communication devices 30 aggregates the measured values of the internal pressure of each of the six tires 41 mounted on the corresponding vehicle 40 and transmits them to the tire monitoring device 10.

[0029] Vehicle identification information (vehicle ID) for identifying the corresponding vehicle 40 and position identification information (position ID) for identifying the mounting position of the corresponding tire 41 are attached to the measured value of the internal pressure. Thereby, in the tire monitoring device 10, it becomes possible to identify which vehicle and which position the measured value of the internal pressure transmitted from each communication device 30 corresponds to the tire mounted at. Each of the communication devices 30 transmits the measured value of the internal pressure to the tire monitoring device 10 via a network 50 such as the Internet by wireless communication. The transmission of the measured value of the internal pressure is performed at any time or intermittently. That is, the time-series data of the measured values of the internal pressure for each vehicle 40 and each mounting position of the tire 41 is transmitted to the tire monitoring device 10. The time-series data of the measured values of the internal pressure for each vehicle and each mounting position of the tire is hereinafter referred to as "internal pressure information". The internal pressure information is real-time information indicating the transition of the internal pressure of the tire 41 for each vehicle and each mounting position of the tire.

[0030] The tire monitoring device 10 is a server computer having a function of individually monitoring each of the plurality of tires 41 mounted on each of the plurality of vehicles 40. The tire monitoring device 10 may be installed, for example, at the site where the vehicle 40 operates, or may be installed at a remote location separated from the site.

[0031] Figure 2 is a diagram showing an example of the hardware configuration of the tire monitoring device 10. The tire monitoring device 10 includes a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102, a non-volatile memory 103, an input device 104 including a keyboard and a mouse, a display 105, and a network interface 106. These hardware components are connected to a bus 108.

[0032] The display 105 may be a touch panel display. The network interface 106 is an interface for communicating via a network 50. The communication method may be either wired or wireless. For wireless communication, for example, a method compliant with an existing wireless communication standard such as Wi-Fi (registered trademark) can be applied.

[0033] The non-volatile memory 103 is a non-volatile storage medium such as a hard disk and a flash memory. A tire monitoring program 110 is stored in the non-volatile memory 103. The RAM 102 is a work memory for the CPU 101 to execute processing. The CPU 101 loads the tire monitoring program 110 stored in the non-volatile memory 103 into the RAM 102 and executes processing according to the tire monitoring program 110.

[0034] Figure 3 is a functional block diagram showing an example of the functional configuration of the tire monitoring device 10. The tire monitoring device 10 includes an acquisition unit 11, a detection unit 12, an estimation unit 13, and an output unit 14. When the CPU 101 executes the tire monitoring program 110, the tire monitoring device 10 functions as the acquisition unit 11, the detection unit 12, the estimation unit 13, and the output unit 14.

[0035] The acquisition unit 11 acquires internal pressure information, which is time-series data of measured values of the internal pressure of the tire for each vehicle and for each tire mounting position, transmitted from each of the communication devices 30.

[0036] The detection unit 12 detects an abnormal internal pressure change for each vehicle and each tire mounting position based on the pattern of the internal pressure change (hereinafter referred to as the change pattern) indicated by the internal pressure information acquired by the acquisition unit 11. Here, FIG. 4 is a diagram showing an example of the change pattern of the tire 41 indicated by the internal pressure information. In FIG. 4, the change pattern in the case where a normal internal pressure change occurs is indicated by a solid line, and the change pattern in the case where an abnormal internal pressure change occurs is indicated by a dotted line. Note that "normal internal pressure change" means a decrease in internal pressure due to natural leakage, and "abnormal internal pressure change" means a decrease in internal pressure due to a cause other than natural leakage.

[0037] As shown in FIG. 4, when a normal internal pressure change occurs, the internal pressure of the tire gradually decreases over time. On the other hand, when an abnormal internal pressure change occurs, the rate of decrease in the internal pressure of that tire becomes higher compared to a normal internal pressure change. The detection unit 12 may determine that an abnormal internal pressure change has occurred in the tire 41 when the rate of decrease in the internal pressure of the tire indicated by the internal pressure information (that is, the amount of decrease in the internal pressure of the tire within a predetermined period) exceeds a predetermined value. By the detection unit 12 detecting an abnormal internal pressure change based on the change pattern of the internal pressure, it becomes possible to detect an abnormality in the tire at a stage before the internal pressure of the tire falls below the threshold value. Further, the detection unit 12 may detect an abnormal internal pressure change by mutually comparing the internal pressure information for each of a plurality of tires provided on each of a plurality of vehicles. Since the characteristics of the change pattern in the case where an abnormal internal pressure change occurs are considered to be different from the characteristics of the change pattern in the case where a normal internal pressure change occurs, it is possible to detect an abnormal internal pressure change by mutually comparing the internal pressure information for each of the plurality of tires.

[0038] When the detection unit 12 detects an abnormal internal pressure change, the estimation unit 13 estimates at least one cause that caused the abnormal internal pressure change for the tire in which the abnormal internal pressure change was detected. The estimation unit 13 performs cause estimation based on the change pattern of the internal pressure indicated by the internal pressure information.

[0039] Causes that can lead to changes in the internal pressure of the tire 41 include valve abnormalities, rim cracks, O-ring abnormalities, side cuts, etc. The mode of internal pressure change will vary depending on the cause. That is, the change pattern of the internal pressure will show a specific pattern corresponding to the cause. Therefore, by analyzing the change pattern of the internal pressure indicated by the internal pressure information, it is possible to estimate the cause that caused the change in the internal pressure.

[0040] For example, the estimation unit 13 may estimate the cause that caused the internal pressure change by comparing a plurality of reference patterns associated with each of the plurality of causes that can cause the internal pressure change with the change pattern of the internal pressure indicated by the internal pressure information. More specifically, the estimation unit 13 may estimate, as the cause that caused the internal pressure change, the cause corresponding to the reference pattern that has the highest similarity to the change pattern of the internal pressure indicated by the internal pressure information among the plurality of reference patterns prepared for each cause that can cause the internal pressure change.

[0041] The reference pattern may be a representative pattern or a typical pattern of the internal pressure change caused by the corresponding cause, or may be created based on past examples, for example. FIG. 5 is a diagram showing an example of the reference pattern. In FIG. 5, three reference patterns P1, P2, and P3 are illustrated. The reference pattern P1 is a representative pattern or a typical pattern of the internal pressure change caused by cause A. The reference pattern P2 is a representative pattern or a typical pattern of the internal pressure change caused by cause B. The reference pattern P3 is a representative pattern or a typical pattern of the internal pressure change caused by cause C. Note that FIG. 5 is for facilitating the understanding of the disclosed technology and does not necessarily show that the pattern and the cause phenomenon correspond.

[0042] Further, the estimation unit 13 may estimate the cause of the internal pressure change using a classification model learned by machine learning. The classification model is a model that takes a change pattern as input and outputs the cause corresponding to the input change pattern. The classification model is learned by machine learning using, as learning data, a combination of a change pattern and correct answer data indicating the cause corresponding to the change pattern.

[0043] Further, the estimation unit 13 may estimate the cause of the internal pressure change based on the rate of change of the internal pressure indicated by the internal pressure information. The rate of decrease in the internal pressure of the tire 41 varies depending on the cause. Therefore, it is possible to estimate the cause of the internal pressure change based on the rate of change of the internal pressure indicated by the internal pressure information.

[0044] Further, the estimation unit 13 may estimate the cause of the internal pressure change based on the change pattern of the internal pressure of the tire before and after maintenance indicated by the internal pressure information. For example, as shown in FIG. 6A, if a tire that showed a normal change pattern before maintenance shows an abnormal change pattern after maintenance, the abnormal internal pressure change is considered to be caused by a defective maintenance operation. Therefore, in this case, factors unrelated to the maintenance operation can be excluded as the cause of the abnormal internal pressure change after maintenance, and the cause can be estimated as other than the above.

[0045] On the other hand, as shown in FIG. 6B, if a change pattern showing an abnormal internal pressure change appears before and after the maintenance of the tire, the internal pressure change is considered not to be caused by the parts replaced by the maintenance operation and a defective maintenance operation. Therefore, in this case, factors related to the replaced parts and defective operations can be excluded, and the cause can be estimated as other than the above. Thus, it is possible to estimate the cause based on the change pattern of the internal pressure of the tire before and after maintenance indicated by the internal pressure information.

[0046] During maintenance, it is usually normal to completely release all the air in the tires at once. Therefore, it is possible to regard the point in time when the internal pressure of the tire indicated by the internal pressure information becomes zero as the maintenance time point. Alternatively, the communication device 30 may be accessed from the outside to add information indicating the maintenance time point to the internal pressure information.

[0047] The output unit 14 outputs cause information indicating the cause that causes the internal pressure change estimated by the estimation unit 13. The output unit 14 may upload the cause information to a predetermined website.

[0048] The terminal device 20 is a communication terminal device used by an operator who centrally manages a plurality of vehicles 40. The terminal device 20 may be installed at the site where the plurality of vehicles 40 operate, or may be installed at a remote location separated from the site. Further, the terminal device 20 may be installed in each of the plurality of vehicles 40. In this case, the terminal device 20 may be used by the driver of each vehicle 40.

[0049] By accessing the website to which the cause information has been uploaded by the terminal device 20, it is possible to display the cause information on a display (not shown) of the terminal device 20. Thereby, the operator can grasp in real time that an abnormal internal pressure change has occurred in the tire for each vehicle and for each tire mounting position, and the cause thereof. Note that the output unit 14 may directly transmit the cause information to the terminal device 20.

[0050] FIG. 7 is a flowchart showing an example of the flow of processing performed by the CPU 101 of the tire monitoring device 10 when executing the tire monitoring program 110.

[0051] In step S1, the acquisition unit 11 acquires internal pressure information, which is time-series data of the measured values of the internal pressure of the tires for each vehicle and for each tire mounting position transmitted from each of the communication devices 30.

[0052] In step S2, the detection unit 12 determines whether an abnormal internal pressure change has occurred for each vehicle and each tire mounting position based on the internal pressure change pattern indicated by the internal pressure information acquired in step S1. If an abnormal internal pressure change is detected, the process proceeds to step S3. If no abnormal internal pressure change is detected, the process returns to step S1.

[0053] In step S3, the estimation unit 13 estimates at least one cause that has caused the abnormal internal pressure change for the tire for which the abnormal internal pressure change has been detected, based on the internal pressure change pattern indicated by the internal pressure information acquired in step S1.

[0054] In step S4, the output unit 14 outputs cause information indicating the cause that causes the internal pressure change estimated in step S3. The output unit 14 may upload the cause information to a predetermined website.

[0055] By accessing the above-mentioned predetermined website by the terminal device 20, the cause information output in step S4 is displayed on the display (not shown) of the terminal device 20. Thereby, the operator using the terminal device 20 can grasp in real time that an abnormal internal pressure change has occurred in the tire for each vehicle and each tire mounting position and the cause thereof. Note that the output unit 14 may directly transmit the cause information to the terminal device 20 in step S4.

[0056] FIG. 8 is a diagram showing an example of the display form of the cause information displayed on the display of the terminal device 20. The cause information is provided with vehicle identification information (vehicle ID) for identifying the corresponding vehicle and position identification information (position ID) for identifying the mounting position of the corresponding tire. The cause information is displayed in a manner that enables grasping which of a plurality of pre-assumed causes the estimated cause is. The cause information may be displayed in a list form as exemplified in FIG. 8, for example.

[0057] As described above, the tire monitoring device 10 according to the first embodiment of the disclosed technology includes an acquisition unit 11 that acquires internal pressure information indicating the transition of the internal pressure of a tire, a detection unit 12 that detects an abnormal internal pressure change based on a change pattern indicated by the internal pressure information, an estimation unit 13 that estimates at least one cause that causes the internal pressure change based on the pattern of the internal pressure change indicated by the internal pressure information for the tire in which the abnormal internal pressure change is detected, and an output unit 14 that outputs cause information indicating the estimated cause.

[0058] According to the existing TPMS, although it is possible to issue an alarm when the internal pressure of a tire decreases, it is not possible to estimate and notify the cause of the internal pressure decrease. For this reason, as shown in FIG. 9A, for an abnormality that cannot be eliminated only by refilling air, the response is limited to just refilling air, and a case may occur where an abnormality is noticed while repeatedly refilling air in response to frequently issued alarms. Until the abnormality is noticed, the tire will be used at an internal pressure outside the appropriate range. As a result, the durability of the tire decreases, and customer values such as safety and long-term use are damaged. In addition, multiple causes can be considered as the cause of the internal pressure decrease of the tire. For this reason, at the maintenance site, it is necessary to perform multiple inspections to investigate the cause, and the work at the site has become complicated.

[0059] Further, since the time required for maintenance work varies greatly depending on the cause of the internal pressure decrease, it is difficult to predict the work time in a situation where the cause is unknown. When the work time is longer than planned, it is necessary to correct the original maintenance plan. On the other hand, when the work time is shorter than planned, losses such as available personnel occur.

[0060] Furthermore, among the parts that need to be replaced in maintenance work, there are those with high acquisition costs and those that require time to obtain, and in many cases, a relatively long lead time is required from the maintenance plan to execution. In a situation where the cause of the internal pressure decrease is unknown, it is not possible to identify the parts to be replaced, and it is also difficult to formulate a maintenance plan.

[0061] According to the tire monitoring device 10 according to the first embodiment of the disclosed technology, for a tire in which an abnormal internal pressure change is detected, the cause thereof is estimated, and cause information indicating the estimated cause is presented. Therefore, as shown in FIG. 9B, it is possible to immediately take appropriate measures after the abnormality is detected. In other words, it is possible to avoid a situation where appropriate measures are not taken without noticing the abnormality for a long period of time.

[0062] Further, according to the tire monitoring device 10, since the cause of the internal pressure change is estimated, it is possible to omit part or all of the inspections for cause investigation, and it is possible to reduce the burden of maintenance work. Furthermore, by estimating the cause of the internal pressure change, the time required for maintenance work can be predicted, and the parts that need to be replaced can also be grasped. As a result, it is possible to formulate a maintenance plan at a relatively early stage.

[0063] As described above, according to the tire monitoring device 10 according to the first embodiment of the disclosed technology, it is possible to assist in investigating the cause of the internal pressure change of the tire.

[0064] [Second Embodiment] FIG. 10 is a functional block diagram showing an example of the functional configuration of a tire monitoring device 10A according to the second embodiment of the disclosed technology. The tire monitoring device 10A includes an acquisition unit 11, a prediction unit 15, and an output unit 14. When the CPU 101 executes the tire monitoring program 110, the tire monitoring device 10A functions as the acquisition unit 11, the prediction unit 15, and the output unit 14.

[0065] The acquisition unit 11 acquires internal pressure information, which is time-series data of measured values of the internal pressure of the tire for each vehicle and for each mounting position of the tire, transmitted from each of the communication devices 30.

[0066] The prediction unit 15 predicts the timing (hereinafter referred to as the threshold arrival timing) at which the internal pressure of the corresponding tire reaches a threshold value based on the change pattern, which is the pattern of the internal pressure change indicated by the internal pressure information. The "threshold value" is, for example, the internal pressure level at which maintenance is recommended. The threshold value can be set to any value. The prediction unit 15 predicts the threshold arrival timing for each vehicle and each tire mounting position based on the change pattern of the internal pressure for each vehicle and each tire mounting position.

[0067] FIGS. 11A and 11B are diagrams showing an example of the mode in which the prediction unit 15 predicts the threshold arrival timing. The prediction unit 15 predicts the threshold arrival timing based on the rate of change of the internal pressure indicated by the internal pressure information. That is, the prediction unit 15 identifies the rate of change of the internal pressure (the slope of the change pattern) at the time of prediction execution, and predicts the date and time when the threshold value is reached when that rate of change is maintained.

[0068] Here, it is assumed that the rate of change of the internal pressure is not constant. For example, when the rate of change of the internal pressure increases as the decrease of the internal pressure progresses, the threshold value will be reached at a timing faster than the initially predicted threshold arrival timing. Therefore, as shown in FIG. 11B, the prediction unit 15 sequentially predicts the threshold arrival timing and sequentially updates the prediction result. Thereby, even when the rate of change of the internal pressure is not constant, it is possible to reduce the deviation between the prediction result and the actual situation. The execution of the prediction by the prediction unit 15 may be regular or irregular.

[0069] The output unit 14 outputs timing information indicating the threshold arrival timing predicted by the prediction unit 15. The output unit 14 sequentially updates and outputs the timing information in response to the sequential prediction of the threshold arrival timing by the prediction unit 15. That is, the prediction unit 15 sequentially performs the process of predicting the threshold arrival timing based on the latest internal pressure information, and the output unit 14 sequentially performs the process of outputting the timing information indicating the latest prediction result. The output unit 14 may upload the timing information to a predetermined website.

[0070] When the terminal device 20 accesses the above-mentioned predetermined website, it is possible to display the timing information output by the output unit 14 on a display (not shown) of the terminal device 20. Thereby, the operator can grasp in advance the timing at which the internal pressure of the tire reaches the threshold value (that is, the timing at which maintenance should be performed) for each vehicle and for each tire mounting position. Note that the output unit 14 may directly transmit the timing information to the terminal device 20.

[0071] FIG. 12 is a flowchart showing an example of the flow of processing performed when the CPU 101 of the tire monitoring device 10A executes the tire monitoring program 110.

[0072] In step S11, the acquisition unit 11 acquires internal pressure information, which is time-series data of measured values of the internal pressure of the tire for each vehicle and for each tire mounting position, transmitted from each of the communication devices 30.

[0073] In step S12, the prediction unit 15 predicts the threshold arrival timing at which the internal pressure of each tire 41 of each vehicle 40 reaches the threshold value based on the change pattern, which is the pattern of the internal pressure change indicated by the internal pressure information acquired in step S11.

[0074] In step S13, the output unit 14 outputs timing information indicating the threshold arrival timing predicted in step S12. The output unit 14 may upload the timing information to a predetermined website.

[0075] When the terminal device 20 accesses the above-mentioned predetermined website, the timing information output in step S13 is displayed on a display (not shown) of the terminal device 20. Thereby, the operator using the terminal device 20 can grasp in advance the timing at which the internal pressure of the tire reaches the threshold value (that is, the timing at which maintenance should be performed) for each vehicle and for each tire mounting position. Note that in step S13, the output unit 14 may directly transmit the timing information to the terminal device 20.

[0076] FIG. 13 is a diagram showing an example of a display form of timing information displayed on the display of the terminal device 20. Vehicle identification information (vehicle ID) for identifying the corresponding vehicle and position identification information (position ID) for identifying the mounting position of the corresponding tire are assigned to the timing information. The timing information may be displayed, for example, using a chart in which the date when the internal pressure of the tire reaches the threshold value is taken on the first axis (horizontal axis) and the change rate of the internal pressure of the tire is taken on the second axis (vertical axis) as shown in FIG. 13. The output unit 14 may output, as timing information, a plot of the prediction result by the prediction unit 15 at the corresponding position of the above chart. By displaying the timing information using the above chart, the operator can easily grasp which tire of which vehicle will reach the threshold value earliest. In addition, since the change rate of the internal pressure of the tire is also displayed, the severity of the situation of each tire can be easily grasped.

[0077] FIG. 14 is a diagram showing another example of a display form of timing information displayed on the display of the terminal device 20. As shown in FIG. 14, the output unit 14 may reflect the cumulative number of past maintenance operations for each vehicle and each tire mounting position in the size of the points plotted on the chart. In the chart shown in FIG. 14, the size of the plotted points increases as the cumulative number of past maintenance operations for the mounting position of the tire of the vehicle increases. Information indicating the cumulative number of maintenance operations for each vehicle and each tire mounting position may be stored, for example, in the non-volatile memory 103 of the tire monitoring device 10A. By reflecting the cumulative number of maintenance operations in the size of the points plotted on the chart, the operator can infer the situation of the tire and the difficulty of response. For example, it is possible to use it as a judgment material when determining the priority order of maintenance implementation for a plurality of tires for which maintenance is planned.

[0078] As described above, the tire monitoring device 10A according to the second embodiment of the disclosed technology includes an acquisition unit 11 that acquires internal pressure information indicating the transition of the internal pressure of the tire, a prediction unit 15 that predicts the timing at which the internal pressure of the tire reaches a threshold value based on the pattern of the internal pressure change indicated by the internal pressure information, and an output unit 14 that outputs timing information indicating the predicted timing.

[0079] Currently, when an alarm is issued from the TPMS, maintenance is performed on the target tire. However, if the target tire can be incorporated into the maintenance plan at a stage before the alarm is issued, it is considered that it will be easier to secure resources such as facilities, parts, and personnel. Also, according to the current response, for example, when an unexpected situation occurs such as a sudden increase in the rate of decrease in internal pressure, an emergency response is required, and the initial maintenance plan may need to be significantly revised. In this case, there is a risk that it will be difficult to secure resources such as facilities, parts, and personnel.

[0080] According to the tire monitoring device 10A according to the second embodiment of the disclosed technology, timing information indicating the timing at which the internal pressure of the tire reaches the threshold value is presented, so it is possible to incorporate the target tire into the maintenance plan at a stage before the internal pressure of the tire reaches the threshold value. As a result, it becomes easier to secure resources such as facilities, parts, and personnel.

[0081] Also, according to the tire monitoring device 10A according to the present embodiment, the prediction of the threshold value arrival timing is sequentially performed and the timing information is sequentially updated, so even when an unexpected situation occurs such as a sudden increase in the rate of decrease in internal pressure, an appropriate prediction result can be obtained. As a result, it is possible to suppress the risk of a significant revision of the maintenance plan occurring.

[0082] As described above, according to the tire monitoring device 10 according to the second embodiment of the disclosed technology, it is possible to support the formulation of a tire maintenance plan.

[0083] FIG. 15 is a functional block diagram showing an example of the functional configuration of the tire monitoring device 10B according to the modified example. The tire monitoring device 10B is different from the above-described tire monitoring device 10A (see FIG. 10) in that it further includes a derivation unit 16.

[0084] Based on the change pattern of the internal pressure indicated by the internal pressure information acquired by the acquisition unit 11 and the threshold arrival timing predicted by the prediction unit 15, the derivation unit 16 derives the priority order of performing maintenance. The derivation unit 16 may derive the priority order based on, for example, the priority Y represented by the following formula (1). In formula (1), X 1 is a score corresponding to the change rate of the internal pressure specified from the change pattern of the internal pressure. X 2 is a score corresponding to the threshold arrival timing predicted by the prediction unit 15. X 3 is a score corresponding to the cumulative number of times of maintenance performed in the past at the tire mounting position of the vehicle. k 1 、k 2 and k 3 are weighting factors. The derivation unit 16 assigns a relatively high priority order to the tire for which the value of the priority Y derived using formula (1) is relatively large. The output unit 14 outputs the priority order derived by the derivation unit 16. Note that, among the scores X 1 、X 2 and X 3 ，the priority may be derived using only one or two of them, or the priority may be derived using other scores other than the above. Y = k 1 ·X 1 + k 2 ·X 2 + k 3 ·X 3 ···(1)

[0085] FIG. 16 is a diagram showing another example of the display form of the timing information displayed on the display of the terminal device 20. As shown in FIG. 16, among the plurality of points plotting the prediction results of the threshold arrival timing, the priority order of performing maintenance for each tire derived by the derivation unit 16 may be displayed in the vicinity of the corresponding point.

[0086] [Third Embodiment] FIG. 17 is a functional block diagram showing an example of the functional configuration of a tire monitoring device 10C according to a third embodiment of the disclosed technology. The tire monitoring device 10C includes an acquisition unit 11, a detection unit 12, an estimation unit 13, a prediction unit 15, a derivation unit 16, and an output unit 14. That is, the tire monitoring device 10C has a configuration combining the tire monitoring device 10 (see FIG. 3) according to the first embodiment described above, the tire monitoring devices 10A (see FIG. 10) and 10B (see FIG. 15) according to the second embodiment. Details of each of the above functional units are as described above.

[0087] FIG. 18 is a flowchart showing an example of the flow of processing performed by the CPU 101 of the tire monitoring device 10C by executing a tire monitoring program 110.

[0088] In step S21, the acquisition unit 11 acquires internal pressure information, which is time-series data of measured values of the internal pressure of the tire for each vehicle and each tire mounting position transmitted from each of the communication devices 30.

[0089] In step S22, the detection unit 12 determines, for each vehicle and each tire mounting position, whether an abnormal change in internal pressure has occurred based on the pattern of change in internal pressure indicated by the internal pressure information acquired in step S21. If an abnormal change in internal pressure is detected, the process proceeds to step S23, and if no abnormal change in internal pressure is detected, the process returns to step S21.

[0090] In step S23, the estimation unit 13 estimates at least one cause that has caused the abnormal change in internal pressure for the tire in which the abnormal change in internal pressure has been detected, based on the pattern of change in internal pressure indicated by the internal pressure information acquired in step S21.

[0091] In step S24, based on the change pattern, which is the pattern of the internal pressure change indicated by the internal pressure information acquired in step S21, the prediction unit 15 predicts, for each tire 41 of each vehicle 40, the threshold arrival timing at which the internal pressure of the tire reaches the threshold value.

[0092] In step S25, based on the change pattern of the internal pressure indicated by the internal pressure information acquired in step S21 and the threshold arrival timing predicted in step S24, the derivation unit 16 derives the priority order of performing maintenance. The derivation unit 16 may use the determination result in step S22 as an element for deriving the priority order.

[0093] In step S26, the output unit 14 outputs the timing information indicating the threshold arrival timing predicted in step S24 and the priority order derived in step S25. Note that the output unit 14 may output cause information indicating the cause of the internal pressure change estimated in step S23 together with the timing information and the priority order. The output unit 14 may upload each of the above information to a predetermined website.

[0094] By accessing the predetermined website by the terminal device 20, it is possible to display the cause information, the timing information, and the priority order output by the output unit 14 on a display (not shown) of the terminal device 20. FIG. 19 is a diagram showing an example of the display form of each of the above information displayed on the display of the terminal device 20. The timing information may be displayed, for example, using a chart with the date when the internal pressure of the tire reaches the threshold value on the first axis (horizontal axis) and the change rate of the internal pressure of the tire on the second axis (vertical axis) as shown in FIG. 19. The output unit 14 may output, as the timing information, a plot of the prediction result by the prediction unit 15 at the corresponding position on the above chart. Further, among the plurality of points where the prediction results of the threshold arrival timing are plotted, the cause information and the priority order of performing maintenance may be displayed in the vicinity of the corresponding point.

[0095] According to the tire monitoring device 10C according to the third embodiment of the disclosed technology, it is possible to assist in investigating the cause of the tire internal pressure change and formulating a tire maintenance plan.

[0096] [Fourth Embodiment] FIG. 20 is a functional block diagram showing an example of the functional configuration of the tire monitoring device 10D according to the fourth embodiment of the disclosed technology. The tire monitoring device 10D includes an acquisition unit 11, a detection unit 12, an estimation unit 13, a prediction unit 15, a derivation unit 16, an output unit 14, and an identification unit 17. That is, the tire monitoring device 10D has a configuration in which the identification unit 17 is further added to the tire monitoring device 10C (see FIG. 17) according to the above-described third embodiment.

[0097] The identification unit 17 identifies a countermeasure method for the cause estimated by the estimation unit 13. The identification unit 17 may identify a countermeasure method corresponding to the cause estimated by the estimation unit 13, for example, by referring to a database in which the cause of the internal pressure change and the countermeasure method are associated. The above database may be stored in the non-volatile memory 103 of the tire monitoring device 10D. The output unit 14 outputs the countermeasure information indicating the countermeasure method identified by the identification unit 17 together with the cause information.

[0098] In each of the above embodiments, the processing executed by the CPU by loading software (program) may be executed by various processors other than the CPU. Examples of the processor in this case include a PLD (Programmable Logic Device) whose circuit configuration can be changed after manufacturing, such as an FPGA (Field-Programmable Gate Array), and a dedicated electric circuit which is a processor having a circuit configuration designed specifically for executing specific processing, such as an ASIC (Application Specific Integrated Circuit). Further, the above processing may be executed by one of these various processors, or may be executed by a combination of two or more processors of the same type or different types (for example, a plurality of FPGAs, a combination of a CPU and an FPGA, etc.). Further, the hardware structure of these various processors is more specifically an electric circuit combining circuit elements such as semiconductor elements.

[0099] Also, in each of the above embodiments, the mode in which the tire monitoring program is pre-stored (installed) in the storage device has been described, but the present invention is not limited to this. The program may be provided in a form recorded on a recording medium such as a CD-ROM, a DVD-ROM (Digital Versatile Disc Read Only Memory), and a USB (Universal Serial Bus) memory. Further, the program may be in a form downloaded from an external device via a network.

[0100] [Contribution to the Sustainable Development Goals (SDGs) Led by the United Nations] Towards the realization of a sustainable society, the SDGs have been proposed. One embodiment of the present invention can be a technology that contributes to "No. 12_The responsibility to create, the responsibility to use" and "No. 13_Specific measures against climate change".

Explanation of Signs

[0101] 1 Tire monitoring system 10, 10A, 10B, 10C Tire monitoring device 11 Acquisition unit 12 Detection unit 13 Estimation unit 14 Output unit 15 Prediction unit 16 Derivation unit 20 Terminal device 30 Communication device 40 Vehicle 41 Tire 42 Inner pressure sensor 50 Network 101 CPU 102 RAM 103 Non-volatile memory 104 Input device 105 Display 106 Network interface 108 Bus 110 Tire monitoring program Patterns for reference P1, P2, P3

Claims

1. An acquisition unit that acquires internal pressure information indicating a change in internal pressure of a tire; an estimation unit that estimates at least one cause of the internal pressure change based on a change pattern that is a pattern of the internal pressure change indicated by the internal pressure information; an output unit that outputs cause information indicating the estimated cause; A tire monitoring device comprising:

2. A detection unit that detects an abnormal internal pressure change based on the change pattern indicated by the internal pressure information, The estimation unit estimates the cause of an abnormal internal pressure change detected in a tire.

2. The tire monitoring device of claim 1.

3. The estimation unit estimates the cause based on a rate of change in the internal pressure indicated by the internal pressure information.

2. The tire monitoring device of claim 1.

4. The estimation unit estimates the cause by comparing a plurality of reference patterns corresponding to each of a plurality of causes of the internal pressure change with the change pattern.

2. The tire monitoring device of claim 1.

5. The estimation unit estimates the cause based on the change pattern before and after maintenance, which is indicated by the internal pressure information.

2. The tire monitoring device of claim 1.

6. The estimation unit estimates the cause using a classification model that is trained by machine learning and that has the change pattern as an input and the cause as an output.

2. The tire monitoring device of claim 1.

7. The output unit outputs the cause information to a predetermined device and / or uploads the cause information to a website.

2. The tire monitoring device of claim 1.

8. The acquisition unit acquires the internal pressure information for each of a plurality of tires provided on each of a plurality of vehicles, The estimation unit estimates the cause for each vehicle and each tire mounting position, The output unit outputs the cause information for each vehicle and each tire mounting position.

2. The tire monitoring device of claim 1.

9. The acquisition unit acquires the internal pressure information for each of a plurality of tires provided on each of a plurality of vehicles, The detection unit detects an abnormal change in internal pressure by comparing the internal pressure information of each of the plurality of tires with each other.

3. The tire monitoring device of claim 2.

10. The present invention further includes a specification unit that specifies a countermeasure for the cause estimated by the estimation unit, and the output unit outputs countermeasure information indicating the specified countermeasure together with the cause information. The tire monitoring device according to any one of claims 1 to 9.

11. Acquire internal tire pressure information that shows the change in internal tire pressure, estimating at least one cause of the internal pressure change based on a change pattern that is a pattern of the internal pressure change indicated by the internal pressure information; outputting cause information indicating the estimated cause; A tire monitoring method in which processing is performed by a computer.

12. Acquire internal tire pressure information that shows the change in internal tire pressure, estimating at least one cause of the internal pressure change based on a change pattern that is a pattern of the internal pressure change indicated by the internal pressure information; Output cause information indicating the estimated cause A tire monitoring program for causing a computer to execute processing.

Images