Abnormality detection system, method and program

Abstract

To detect abnormality of vehicle tire inner pressure through an angular velocity of a wheel without using a sensor mounted on a vehicle.SOLUTION: A processing circuit is configured to perform: acquisition of a plurality of first images captured while a vehicle is travelling so as to include a two-dimensional code of a plurality of wheels; acquisition of a plurality of second images captured while the vehicle is travelling with a predetermined time interval from the capturing time of the first image so as to include the two-dimensional code of the plurality of wheels; calculation of a rotational displacement amount of the corresponding two-dimensional code direction for the second image with respect to the corresponding two-dimensional code direction for the first image for each wheel; calculation of the angular velocity for each wheel based on the corresponding rotational displacement amount and the time interval; and determination on whether a tire with abnormality in inner pressure exists among a plurality of wheel tires based on the angular velocities of the plurality of wheels.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a system, method, and program for detecting an abnormality in internal pressure of a tire in a vehicle. [Background technology]

[0002] Conventionally, methods for detecting abnormalities in the internal pressure of tires of vehicle wheels have been proposed. Patent Document 1 discloses a method for detecting deflated tires on a vehicle having four wheels. In this detection method, the angular velocity of the four wheels is detected, signals proportional to the angular velocity are generated, and the four signals are processed to determine whether some or all of the four tires are deflated. Patent Document 1 describes that the angular velocity of the vehicle wheels is measured by a digital pulse oscillator disposed in association with each wheel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 63-305011 Summary of the Invention [Problem to be solved by the invention]

[0004] The method of detecting abnormal internal pressure in a tire disclosed in Patent Document 1 requires that a sensor for measuring the angular velocity of each wheel be mounted on the vehicle.

[0005] The present disclosure aims to provide an abnormality detection system, method, and program that can detect an abnormality in the internal pressure of a vehicle's tires by obtaining the angular velocity of the wheels without using a sensor mounted on the vehicle. [Means for solving the problem]

[0006] An abnormality detection system according to one embodiment of the present disclosure is an abnormality detection system for detecting an internal pressure abnormality in a tire of a vehicle including a tire, a tire wheel on which the tire is mounted, and a plurality of wheels including a two-dimensional code disposed on a side of the tire wheel, the abnormality detection system including a processing circuit configured to: acquire a plurality of first images captured while the vehicle is traveling, the first images including the two-dimensional codes of the plurality of wheels; acquire a plurality of second images captured while the vehicle is traveling at a predetermined time interval from the time when the first images were captured, the second images including the two-dimensional codes of the plurality of wheels; calculate, for each of the wheels, an amount of rotational displacement of an orientation of the corresponding two-dimensional code in the second image relative to an orientation of the corresponding two-dimensional code in the first image; calculate, for each of the wheels, an angular velocity of each of the wheels based on the corresponding amount of rotational displacement and the time interval; and determine whether or not a tire with an internal pressure abnormality is present among the tires of the plurality of wheels based on the angular velocities of the plurality of wheels.

[0007] An abnormality detection method according to one embodiment of the present disclosure is an abnormality detection method for detecting an internal pressure abnormality in a tire of a vehicle having a tire, a tire wheel on which the tire is mounted, and a plurality of wheels including a two-dimensional code disposed on a side of the tire wheel, the abnormality detection method including: acquiring a plurality of first images taken while the vehicle is traveling, the first images including the two-dimensional codes of the plurality of wheels; acquiring a plurality of second images taken while the vehicle is traveling at a predetermined time interval from the time when the first images are taken, the second images including the two-dimensional codes of the plurality of wheels; calculating, for each of the wheels, an amount of rotational displacement of an orientation of the corresponding two-dimensional code in the second image relative to an orientation of the corresponding two-dimensional code in the first image; calculating, for each of the wheels, an angular velocity of each of the wheels based on the corresponding amount of rotational displacement and the time interval; and determining whether or not a tire with an internal pressure abnormality is present among the tires of the plurality of wheels based on the angular velocities of the plurality of wheels.

[0008] An anomaly detection program according to an embodiment of the present disclosure causes at least one processor to execute the anomaly detection method. The program may be stored in a computer-readable storage medium. The storage medium is a non-transitory and tangible medium. The storage medium may be built into or externally attached to a computer (e.g., a mobile information terminal, a personal computer, a server, etc.). The storage medium may include RAM, ROM, EEPROM, storage, etc., and may be, for example, a hard disk, a flash memory, an optical disk, etc. The program stored in the storage medium may be executed in a computer to which the storage medium is directly connected, or may be executed in a computer connected to the storage medium via a communication network (e.g., the Internet). Effect of the Invention

[0009] According to one aspect of the present disclosure, an abnormality in the internal pressure of a vehicle tire can be detected by obtaining the angular velocity of the wheel without using a sensor mounted on the vehicle. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of an anomaly detection system according to an embodiment. [Diagram 2] FIG. 2 shows an example of the arrangement of a plurality of cameras, in which a moving vehicle and a plurality of cameras capturing images of the vehicle are viewed from the front. [Diagram 3] FIG. 3 shows an example of the arrangement of a plurality of cameras, in which a traveling vehicle and a plurality of cameras capturing images of the vehicle are viewed from above. [Figure 4] FIG. 4 is a side view of the wheel. [Diagram 5] FIG. 5 is a block diagram of various devices included in the anomaly detection system of FIG. [Figure 6] FIG. 6 is a flowchart illustrating the process of the anomaly detection system of FIG. [Figure 7] FIG. 7 is a diagram showing an example of a first image captured while the vehicle is traveling. [Figure 8]FIG. 8 is a diagram showing a second image captured a predetermined time interval after the first image is captured. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment will be described with reference to the drawings.

[0012] <Overall system configuration> 1 is a schematic diagram of an anomaly detection system 1 according to an embodiment. The anomaly detection system 1 is for detecting an abnormality in the internal pressure of a tire of a vehicle 2. The vehicle 2 to be inspected for the presence or absence of an abnormality in the internal pressure of the tire (hereinafter, may also be referred to as the inspection target vehicle 2) includes four or more wheels 10. The multiple wheels 10 of the inspection target vehicle 2 include, for example, two front wheels 10 opposed in the left-right direction, and two rear wheels 10 opposed in the left-right direction behind the two front wheels 10. The inspection target vehicle 2 is, for example, a passenger car, a truck, a bus, etc.

[0013] The anomaly detection system 1 includes a plurality of vehicle inspection systems 3 which may be distributed across multiple locations distant from one another. The anomaly detection system 1 also includes a server 4 and a plurality of information processing terminals 5. The vehicle inspection systems 3, the server 4, and the plurality of information processing terminals 5 are connected to a communication network N such as the Internet. The communication network N is not limited to the Internet, and may be other networks such as a LAN, a WAN, a satellite communication line, or a mobile phone network.

[0014] Each vehicle inspection system 3 acquires an image of the wheels 10 of the vehicle 2 to be inspected. In this embodiment, the vehicle inspection system 3 determines whether any of the tires of the multiple wheels 10 has an abnormal internal pressure from the images of the multiple wheels 10. The server 4 receives the determination results regarding the abnormal internal pressure of the tire from each vehicle inspection system 3 via the communication network N and stores them as inspection data of the vehicle 2 to be inspected. The server 4 may be, for example, a cloud server.

[0015] The information processing terminal 5 receives and outputs the inspection data of the vehicle 2 to be inspected from the server 4. The user of the information processing terminal 5 may be, for example, an administrator of the server 4, an administrator of the vehicle 2 to be inspected, a passenger such as a driver of the vehicle 2 to be inspected, or an owner of the vehicle 2 to be inspected. The user of the information processing terminal 5 can check the inspection data of the vehicle 2 to be inspected via the information processing terminal 5. For example, the information processing terminal 5 may be an in-vehicle terminal mounted on the vehicle 2 to be inspected. The information processing terminal 5 may be a mobile terminal of a passenger of the vehicle 2 to be inspected. The information processing terminal 5 may be a smartphone, a laptop computer, or a tablet terminal. The information processing terminal 5 may be a personal computer installed in a management company that manages the vehicle 2 to be inspected.

[0016] The vehicle inspection system 3 includes a data processing device 6 and a plurality of cameras 7 communicably connected to the data processing device 6. The plurality of cameras 7 and the data processing device 6 may be connected by wire or wirelessly.

[0017] <Camera placement> 2 and 3 show examples of the arrangement of the multiple cameras 7. FIG. 2 is a view of the vehicle 2 to be inspected while traveling and the multiple cameras 7 that image the vehicle 2, as seen from the front. FIG. 3 is a view of the vehicle 2 to be inspected while traveling and the multiple cameras 7 that image the vehicle 2, as seen from above. In FIG. 3, the body 14 of the vehicle 2 is indicated by a two-dot chain line. As shown in FIG. 2, the multiple cameras 7 may be installed at a height approximately equal to that of the wheels 10, for example, so that at least a portion of the wheels 10 can be imaged. The multiple cameras 7 are installed at a location where the vehicle 2 travels in a straight line at a low speed. For example, the multiple cameras 7 may be installed at a location such as the entrance to a garage, but the installation location is not particularly limited.

[0018] In FIG. 3, the vehicle 2 to be inspected includes four wheels 10, and the vehicle inspection system 3 includes the same number of cameras 7 as the vehicle 2 to be inspected. Specifically, the vehicle inspection system 3 includes a first camera 7a for imaging the left front wheel 10a of the vehicle 2 to be inspected, a second camera 7b for imaging the right front wheel 10b of the vehicle 2 to be inspected, a third camera 7c for imaging the left rear wheel 10c of the vehicle 2 to be inspected, and a fourth camera 7d for imaging the left rear wheel 10d of the vehicle 2 to be inspected. The four cameras 7 shown in FIG. 3 are arranged so as to simultaneously image the four wheels 10 of the vehicle 2 to be inspected. That is, the distance in the front-rear direction between the first camera 7a and the second camera 7b and the third camera 7c and the fourth camera 7d is approximately the same as the distance between the front wheels 10a, 10b and the rear wheels 10c, 10d of the vehicle 2 to be inspected.

[0019] 2 and 3 are merely examples. For example, the number of cameras 7 included in the vehicle inspection system 3 may be more or less than the number of wheels 10 of the vehicle 2 to be inspected.

[0020] FIG. 4 is a side view of a wheel 10. The wheel 10 of the vehicle 2 to be inspected includes a tire 11 and a tire wheel 12 to which the tire 11 is attached. At least one two-dimensional code 13 is arranged on the side of the tire wheel 12. The two-dimensional code 13 may be a sticker attached to the side of the tire wheel 12, or may be directly formed on the side of the tire wheel 12 by a laser or the like. In the example of FIG. 4, a first two-dimensional code 13a and a second two-dimensional code 13b are arranged on the side of the tire wheel 12. The first two-dimensional code 13a is arranged at a distance slightly away from the axle in a direction perpendicular to the axle. The second two-dimensional code 13b is arranged on an extension line of the axle. The two-dimensional codes 13a and 13b are, for example, QR codes (registered trademark), but may be other types of two-dimensional codes as long as the angle of the two-dimensional code can be detected on an image.

[0021] 4, the imaging area R of the camera 7 is indicated by a two-dot chain line. The camera 7 is installed so that the wheels 10 are included in the imaging area R of the camera 7 when the vehicle 2 passes through a predetermined location such as the entrance to a garage. The imaging area R may include the entire wheels 10, rather than only a portion of the wheels 10.

[0022] <Hardware configuration> FIG. 5 is a block diagram of various devices included in the anomaly detection system 1 of FIG. 1. FIG. 5 includes a block diagram of one of the multiple vehicle inspection systems 3 included in the anomaly detection system 1. As shown in FIG. 5, the data processing device 6 includes a processing circuit 20, a user interface 24, and a communication interface 25. The processing circuit 20 includes a processor 21, a system memory 22, and a storage memory 23. The processor 21 may include a CPU. The system memory 22 may include a RAM. The storage memory 23 may include a hard disk, a flash memory, or a combination thereof. The storage memory 23 stores a program 23a. A configuration in which the processor 21 executes the program 23a read from the storage memory 23 to the system memory 22 is an example of the processing circuit 20, and the program 23a is an example of an anomaly detection program.

[0023] The user interface 24 includes an input interface and an output interface. The input interface includes at least one of a touch panel, a keyboard, a mouse, a microphone, etc. The output interface includes at least one of a display, a projector, a lamp, a speaker, etc. The communication interface 25 includes an interface for communicatively connecting to the communication network N in a wired or wireless manner. The communication interface 25 also includes a communication interface for connecting to the camera 7. The camera 7 is a digital optical machine for capturing digital images.

[0024] 5 includes a block diagram of the server 4 included in the anomaly detection system 1. The server 4 includes a processing circuit 30 and a communication interface 34. The processing circuit 30 includes a processor 31, a system memory 32, and a storage memory 33. The processor 31 may include a CPU. The system memory 32 may include a RAM. The storage memory 33 may include a hard disk, a flash memory, or a combination thereof. The storage memory 33 stores a program 33a. The communication interface 34 includes a communication interface that is communicatively connected to the communication network N in a wired or wireless manner.

[0025] 5 includes a block diagram of one of a plurality of information processing terminals 5 included in the anomaly detection system 1. The information processing terminal 5 includes a processing circuit 40, a user interface 44, and a communication interface 45. The processing circuit 40 includes a processor 41, a system memory 42, and a storage memory 43. The processor 41 may include a CPU. The system memory 42 may include a RAM. The storage memory 43 may include a hard disk, a flash memory, or a combination thereof. The storage memory 43 stores a program 43a.

[0026] The user interface 44 includes an input interface and an output interface. The input interface includes at least one of a touch panel, a keyboard, a mouse, a microphone, etc. The output interface includes at least one of a display, a projector, a speaker, etc. The communication interface 45 includes a communication interface that is communicatively connected to the communication network N in a wired or wireless manner.

[0027] <Anomaly detection processing> Fig. 6 is a flowchart for explaining anomaly detection processing in the anomaly detection system 1 of Fig. 1. In this embodiment, the entire anomaly detection processing shown in Fig. 6 is executed by the processing circuit 20 of the data processing device 6. However, a part or the entire anomaly detection processing may be executed by the processing circuit 30 of the server 4, or may be executed by the processing circuit 40 of the information processing terminal 5.

[0028] The abnormality detection process of this embodiment is executed every time the inspection target vehicle 2 passes in a predetermined direction through a location where the vehicle inspection system 3 is installed. For example, if the camera 7 is installed at the entrance to a garage, the abnormality detection process may be executed every time the inspection target vehicle 2 enters the garage.

[0029] The vehicle inspection system 3 may include a vehicle detection sensor 8. For example, the vehicle detection sensor 8 may be installed at a predetermined location such as the entrance to a garage, and the data processing device 6 may start the abnormality detection process when it receives information from the vehicle detection sensor 8 that the vehicle 2 has been detected. In this case, the multiple cameras 7 are in a stopped state until the vehicle detection sensor 8 detects the vehicle 2, and the data processing device 6 may start the operation of the multiple cameras 7 when it receives information from the vehicle detection sensor 8 that the vehicle 2 has been detected. For example, the vehicle detection sensor 8 may be a well-known vehicle detection sensor that uses infrared rays or microwaves.

[0030] Furthermore, the vehicle inspection system 3 does not necessarily have to include the vehicle detection sensor 8. For example, the camera 7 may be constantly operating, and the data processing device 6 may start the abnormality detection process when it determines that the two-dimensional code 13 is included in the image captured by the camera 7 by a known two-dimensional code recognition technology.

[0031] In the abnormality detection process, first, the data processing device 6 acquires a plurality of first images captured from the plurality of cameras 7 while the vehicle 2 is traveling at a low speed so as to include the two-dimensional codes 13 on the plurality of wheels 10 (step S1). The data processing device 6 acquires a plurality of second images captured while the vehicle 2 is traveling at a low speed at a predetermined time interval from the capture of the first images so as to include the two-dimensional codes 13 on the plurality of wheels 10 (step S2). For example, each of the first image P1 and the second image P2 may be a frame constituting a moving image captured by the camera 7 at a predetermined frame rate.

[0032] The data processing device 6 reads the recorded information of the two-dimensional code 13 in the first image and the second image for each wheel 10 by image processing (step S3). The recorded information of the two-dimensional code 13 includes code ID information indicating identification information of the two-dimensional code itself. The recorded information of the two-dimensional code 13 may include wheel identification information which is identification information of the wheel 10 including the two-dimensional code 13. The recorded information of the two-dimensional code 13 may include vehicle identification information which is identification information of the vehicle to be inspected which is equipped with the wheel 10 including the two-dimensional code 13.

[0033] After step S3, the data processing device 6 calculates, for each wheel 10, the amount of rotational displacement of the orientation of the corresponding two-dimensional code 13 in the second image relative to the orientation of the corresponding two-dimensional code 13 in the first image (step S4). For example, the data processing device 6 calculates the orientation (i.e., posture) of the two-dimensional code 13 in the first image by a known two-dimensional code recognition technique, and calculates the orientation (i.e., posture) of the two-dimensional code 13 in the second image. The data processing device 6 calculates the amount of rotational displacement of the orientation of the two-dimensional code 13 by comparing the orientations of these two-dimensional codes 13.

[0034] The data processing device 6 calculates the angular velocity of each wheel 10 based on the amount of rotational displacement corresponding to the wheel 10 and the time interval between capturing the first image and the second image (step S5).

[0035] Steps S1 to S5 will be specifically described with reference to Figures 7 and 8. Figure 7 is a diagram showing an example of a first image P1 captured while the vehicle 2 is traveling. Figure 8 is a diagram showing a second image P2 captured a predetermined time interval t after the first image P1 in Figure 7 is captured.

[0036] 7 and 8, the first image P1 and the second image P2 include a two-dimensional code 13. In the two-dimensional code 13, which is a QR code (registered trademark), the position, size, and angle (tilt) of the two-dimensional code 13 on the image can be detected by identifying the finder patterns at three of the four corners of a square. Therefore, the attitude of the two-dimensional code 13 with respect to a predetermined reference plane can be known.

[0037] For example, the two-dimensional code 13, which is a QR code (registered trademark), has finder patterns at three of the four corners of a square, and the basic posture may be the posture when the finder patterns are at the upper right corner, upper left corner, and lower left corner. For example, the data processing device 6 calculates the angle θ1 between the upper side (the side connecting the finder pattern at the upper left corner and the finder pattern at the upper right corner) of the two-dimensional code 13 in the first image P1 and the horizontal axis X on the first image P1 as the orientation of the two-dimensional code 13 in the first image P1, and calculates the angle θ2 between the upper side of the two-dimensional code 13 in the second image P2 and the horizontal axis X on the second image P2 as the orientation of the two-dimensional code 13 in the second image P2. Note that the method of calculating the angle of the two-dimensional code 13, which is a QR code (registered trademark), is not limited to this, and other known methods (for example, angle calculation based on a change in width of the finder pattern) may be used.

[0038] The data processing device 6 calculates the relative angle (θ2-θ1) between the two-dimensional code 13 in the first image P1 and the two-dimensional code 13 in the second image P2 as the amount of rotational displacement of the orientation of the two-dimensional code 13. The data processing device 6 also calculates the angular velocity ω of each wheel 10 by dividing the relative angle (θ2-θ1) by the time interval t between the capture of the first image P1 and the capture of the second image P2. For example, if the first image P1 and the second image P2 are two consecutive frames constituting a moving image captured by the camera 7 at a predetermined frame rate, the time interval t is a time indicated by the reciprocal of the frame rate.

[0039] Returning to Fig. 6, the data processing device 6 determines whether or not any of the tires 11 of the multiple wheels 10 has an abnormal internal pressure, based on the angular velocities of the multiple wheels 10 (step S6). There are several possible methods for determining whether or not a tire 11 has an abnormal internal pressure using the angular velocities of the wheels 10. Depending on the determination method, determining whether or not any of the tires 11 of the multiple wheels 10 has an abnormal internal pressure may include identifying which of the tires 11 of the multiple wheels 10 has an abnormal internal pressure.

[0040] Several examples of methods for determining whether the internal pressure of the tire 11 is abnormal using the angular velocity of the wheel 10 will be described. For ease of explanation, it will be assumed that the vehicle 2 to be inspected, for which the internal pressure of the tire 11 is determined to be abnormal using the following method, is a four-wheeled vehicle including a left front wheel 10a, a right front wheel 10b, a left rear wheel 10c, and a left rear wheel 10d, and that in step S5, the data processing device 6 calculates the angular velocity ωa of the left front wheel 10a, the angular velocity ωb of the right front wheel 10b, the angular velocity ωc of the left rear wheel 10c, and the angular velocity ωd of the left rear wheel 10d.

[0041] (Judgment method 1) Determination method 1 is a method for determining whether or not a tire 11 with abnormal internal pressure is present in either of the two wheels 10 by comparing the angular velocities of two wheels 10 among a plurality of wheels 10 included in the vehicle 2 to be inspected. Determination method 1 utilizes the difference in angular velocities between a wheel 10 including a tire 11 with no abnormal internal pressure and a wheel 10 including a tire 11 with abnormal internal pressure, making it possible to determine in a simple manner whether or not a tire 11 with abnormal internal pressure is present.

[0042] For example, a case will be described in which it is determined whether or not there is an abnormality in one of the tires 11, the left front wheel 10a and the right front wheel 10b, in the determination method 1. The data processing device 6 calculates the difference |ωa-ωb| between the angular velocity ωa of the left front wheel 10a and the angular velocity ωb of the right front wheel 10b. After that, the data processing device 6 divides the difference |ωa-ωb| by the angular velocity ωa of the left front wheel 10a and the angular velocity ωb of the right front wheel 10b, respectively, to calculate two evaluation values ​​(i.e., |ωa-ωb| / ωa and |ωa-ωb| / ωb). After that, the data processing device 6 determines whether or not each of the two evaluation values ​​exceeds a predetermined limit value L1. If the data processing device 6 determines that either of the two evaluation values ​​exceeds the predetermined limit value L1, it determines that there is an internal pressure abnormality in the tire 11, either the left front wheel 10a or the right front wheel 10b.

[0043] Furthermore, when the data processing device 6 determines that either of the two evaluation values ​​exceeds a predetermined limit value L1, it can identify that the tire 11 having the larger angular velocity out of the left front wheel 10a and the right front wheel 10b has an internal pressure abnormality. The reason for determining that the tire 11 having the larger angular velocity has an internal pressure abnormality is that the angular velocity of a tire with an internal pressure abnormality is greater than the angular velocity of a normal tire without an internal pressure abnormality.

[0044] The above-described determination method 1 can be expressed in another way as follows: In order to determine whether the internal pressure of the tire 11 of the left front wheel 10a is abnormal, the data processing device 6 sets the value |ωa-ωb| / ωb obtained by dividing the angular velocity difference |ωa-ωb| by the angular velocity ωb of the right front wheel 10b as an evaluation value, and determines whether the evaluation value |ωa-ωb| / ωb satisfies the following formula (1). |ωa-ωb| / ωb>L1 (1) When the data processing device 6 determines that the formula (1) is satisfied, it determines that there is an abnormality in the internal pressure of the tire 11 of the left front wheel 10a. The evaluation value exceeding the limit value L1, that is, formula (1) is the abnormality determination condition for determining that there is an abnormality in the internal pressure of the tire 11 of the left front wheel 10a.

[0045] Similarly, in order to determine whether the internal pressure of the tire 11 of the right front wheel 10b is abnormal, the data processing device 6 sets the value |ωa-ωb| / ωa obtained by dividing the angular velocity difference |ωa-ωb| by the angular velocity ωa of the left front wheel 10a as an evaluation value, and determines whether the evaluation value |ωa-ωb| / ωa satisfies the following equation (2). |ωa-ωb| / ωa>L1 (2) When the data processing device 6 determines that the formula (2) is satisfied, it determines that there is an internal pressure abnormality in the tire 11 of the right front wheel 10b. The evaluation value exceeding the limit value L1, that is, formula (2) is the abnormality determination condition for determining that there is an internal pressure abnormality in the tire 11 of the right front wheel 10b.

[0046] The above describes judgment method 1 using an example of determining whether or not there is an abnormality in one of the tires 11, either the left front wheel 10a or the right front wheel 10b. However, a similar method can also be used to determine whether or not there is an abnormality in one of the tires 11, either the left rear wheel 10c or the right rear wheel 10d.

[0047] In the above-described determination method 1, the angular velocities of the two wheels 10 facing each other in the left-right direction are compared, but the combination of the wheels 10 whose angular velocities are compared is not limited to this. For example, the angular velocities of the two wheels 10 arranged in the front-rear direction may be compared. For example, when determining whether or not there is an internal pressure abnormality in one of the tires 11, the left front wheel 10a and the left rear wheel 10c, using the determination method 1, |ωa-ωc| / ωa and |ωa-ωc| / ωc are set as evaluation values ​​instead of |ωa-ωb| / ωa and |ωa-ωb| / ωb. Also, the angular velocities of the two wheels 10 arranged diagonally may be compared. For example, when determining whether or not there is an internal pressure abnormality in one of the tires 11, the left front wheel 10a and the right rear wheel 10d, using the determination method 1, |ωa-ωd| / ωa and |ωa-ωd| / ωd are set as evaluation values ​​instead of |ωa-ωb| / ωa and |ωa-ωb| / ωb.

[0048] (Judgment method 2) Judgment method 2 is a method for judging whether or not the tire 11 of the wheel 10 to be inspected has an abnormal internal pressure by comparing the angular velocity of the wheel 10 to be inspected with the average angular velocity of the multiple wheels 10. By using judgment method 2, it is possible to grasp whether the angular velocity of the wheel 10 to be inspected significantly deviates from the average value of the angular velocities of the multiple wheels 10, and therefore it is possible to easily identify the tire 11 with an abnormal internal pressure.

[0049] For example, a case will be described where whether or not there is an abnormality in the tire 11 of the left front wheel 10a is determined using the determination method 2. First, the data processing device 6 calculates the average angular velocity ωave of the left front wheel 10a, the right front wheel 10b, the left rear wheel 10c, and the left rear wheel 10d by the following formula (3). ωave=(ωa+ωb+ωc+ωd) / 4 ···(3)

[0050] Next, the data processing device 6 divides the angular velocity ωa of the left front wheel 10a by the average angular velocity ωave to calculate an evaluation value ωa / ωave. After that, the data processing device 6 determines whether the evaluation value ωa / ωave exceeds a predetermined limit value L2. That is, the data processing device 6 determines whether the evaluation value ωa / ωave satisfies the following formula (4). ωa / ωave>L2 (4) When the data processing device 6 determines that the formula (4) is satisfied, it determines that there is an internal pressure abnormality in the tire 11 of the left front wheel 10a. The evaluation value exceeding the limit value L2, that is, formula (4), is an abnormality determination condition for determining that there is an internal pressure abnormality in the tire 11 of the left front wheel 10a.

[0051] While the determination method 2 has been described above using an example of determining whether or not there is an abnormality in the tire 11 of the left front wheel 10a, whether or not there is an abnormality in each of the tires 11 of the other wheels 10b, 10c, and 10d can also be determined in a similar manner. For example, when determining whether or not there is an abnormality in the tire 11 of the right front wheel 10b, the left side of equation (4) is replaced with the evaluation value ωb / ωave.

[0052] (Judgment method 3) Judgment method 3 is a method for judging whether or not there is an abnormality in the internal pressure of the tire 11 of the wheel 10 being inspected by comparing the angular velocity of the wheel 10 being inspected with an absolute reference value that is not related to the angular velocities of the other wheels 10. By using judgment method 3, it is possible to perform a judgment appropriate to the characteristics and state of the vehicle 2, and it is possible to accurately judge whether or not there is an abnormality in the internal pressure of the tire 11.

[0053] First, the data processing device 6 acquires vehicle-related information indicating the characteristics of the vehicle 2, the state of the vehicle 2, or a combination of the characteristics of the vehicle 2 and the state of the vehicle 2. Next, the data processing device 6 sets an evaluation value or an abnormality determination condition according to the acquired vehicle-related information. The evaluation value is the angular velocity itself of the wheel 10 for determining whether or not there is an internal pressure abnormality, or a value based on the angular velocity. After that, the data processing device 6 determines whether or not the evaluation value satisfies the abnormality determination condition, and if it is determined that the evaluation value satisfies the abnormality determination condition, it determines that there is an internal pressure abnormality in the tire 11 of the wheel 10 corresponding to the evaluation value.

[0054] For example, a case will be described in which it is determined whether or not there is an abnormality in the tire 11 of the left front wheel 10a using the determination method 3. The data processing device 6 sets the angular velocity ωa of the left front wheel 10a as an evaluation value. The data processing device 6 sets a limit value L3 included in the abnormality determination condition according to the acquired vehicle-related information. The data processing device 6 determines whether or not the angular velocity ωa, which is the evaluation value, exceeds the limit value L3. That is, the data processing device 6 determines whether or not the evaluation value ωa satisfies the following formula (5). ωa>L3 (5) When the data processing device 6 determines that the formula (5) is satisfied, it determines that there is an internal pressure abnormality in the tire 11 of the left front wheel 10a. The evaluation value exceeding the limit value L3, that is, formula (5), is an abnormality determination condition for determining that there is an internal pressure abnormality in the tire 11 of the left front wheel 10a.

[0055] Setting of the limit value L3 according to the vehicle-related information will be described in detail. A correspondence relationship between the vehicle-related information and the limit value L3 is stored in advance in the memory of the data processing device 6. The data processing device 6 sets the limit value L3 corresponding to the acquired vehicle-related information according to the correspondence relationship.

[0056] For example, the vehicle-related information may include at least one of size information indicating the size of the wheels 10 of the vehicle 2 to be inspected, speed information indicating the traveling speed of the vehicle 2 to be inspected, vehicle type information indicating the vehicle type of the vehicle 2 to be inspected, and loading information indicating the weight of the load carried by the vehicle 2 to be inspected. For example, if the memory of the data processing device 6 stores a correspondence relationship between the size and traveling speed of the wheels 10 and the limit value L3, the data processing device 6 sets the limit value L3 corresponding to the acquired size information and speed information in accordance with the correspondence relationship.

[0057] For example, when the vehicle-related information includes size information, the data processing device 6 acquires the size information by reading the recorded information of the two-dimensional code 13 of the wheel 10. For example, the size information may be included in the recorded information of the two-dimensional code 13 of the wheel 10. The size information does not have to be included in the recorded information of the two-dimensional code 13. In this case, a correspondence relationship between the code ID information and the size information of the wheel 10 may be stored in advance in the memory of the data processing device 6 or an external memory, and the data processing device 6 may acquire the size information associated with the code ID information of the read two-dimensional code 13 by referring to the correspondence relationship.

[0058] Furthermore, for example, when the vehicle-related information includes speed information, the vehicle inspection system 3 may include a device capable of measuring or calculating the traveling speed of the inspected vehicle 2. For example, the vehicle inspection system 3 may include a speedometer such as a laser speedometer installed beside the camera 7, and the data processing device 6 may receive the traveling speed measured by the speedometer.

[0059] Alternatively, the vehicle inspection system 3 may include a camera that captures an image of a two-dimensional code placed on the side of the vehicle body 14 of the vehicle 2 to be inspected at a predetermined time interval. The two-dimensional code placed on the side of the vehicle body 14 is, for example, a QR code (registered trademark). The data processing device 6 may calculate the traveling speed by calculating the horizontal displacement amount per unit time of the two-dimensional code on the side of the vehicle body 14 from the moving image or multiple still images received from the camera. Note that instead of including a camera that captures the two-dimensional code on the side of the vehicle body 14 separately from the camera 7 for capturing the two-dimensional code 13, the vehicle inspection system 3 may capture images of both the two-dimensional code 13 on the wheel 10 and the two-dimensional code placed on the side of the vehicle body 14 by the camera 7.

[0060] Alternatively, the data processing device 6 may receive, from the vehicle 2, information relating to the traveling speed measured by a speedometer mounted on the vehicle 2.

[0061] Furthermore, for example, when the vehicle-related information includes loading information, the vehicle inspection system 3 may include equipment capable of measuring or calculating the weight of the vehicle 2 to be inspected. For example, the vehicle inspection system 3 may include a weighing scale beside the camera 7, and the data processing device 6 may calculate the weight of the load carried by the vehicle 2 to be inspected based on the weight received from the weighing scale.

[0062] Alternatively, the data processing device 6 may receive, from the vehicle 2 to be inspected, information regarding the weight of the cargo carried by the vehicle 2 .

[0063] The above-described determination methods 1, 2, and 3 are merely examples. The evaluation value and abnormality determination conditions can be set appropriately. In step S6, two or more of the determination methods 1, 2, and 3 may be used.

[0064] As shown in Fig. 4, when each wheel 10 includes two two-dimensional codes 13 (13a, 13b), the data processing device 6 executes the process of steps S3 to S6 for each two-dimensional code 13. By determining the presence or absence of an abnormality in the internal pressure of the tire 11 using the multiple two-dimensional codes of the wheel 10, the accuracy of the determination can be improved. Also, there are cases where one of the multiple two-dimensional codes 13 included in the wheel 10 cannot be image-recognized due to some factor such as dirt or scratches. Even in such a case, the internal pressure abnormality of the tire 11 can be determined using another two-dimensional code 13.

[0065] After step S6, the data processing device 6 outputs the determination result of step S6 (step S7). Specifically, the data processing device 6 transmits the determination result to the server 4. The determination result is transmitted together with the code ID information. The determination result may be transmitted together with at least one of the wheel identification information and the vehicle identification information so that the tire 11 having the internal pressure abnormality and the vehicle 2 equipped with the tire 11 can be immediately identified. For example, if the determination result indicates that there is no abnormality in any of the tires 11 of the multiple wheels 10, the data processing device 6 does not need to transmit the determination result to the server 4.

[0066] The server 4 stores in the storage memory 33 the determination result that the tire 11 has an abnormal internal pressure in association with the code ID information of the two-dimensional code 13 corresponding to the tire 11 identified as having an abnormal internal pressure.

[0067] The server 4 transmits the determination result that there is an internal pressure abnormality to a pre-designated information processing terminal 5 in association with the code ID information of the two-dimensional code 13 corresponding to the tire 11 identified as having an internal pressure abnormality. For example, the server 4 may transmit the determination result to a destination indicated by the destination information associated with the code ID information of the two-dimensional code 13. For example, the server 4 may not need to transmit the determination result to the information processing terminal 5 when the determination result is that there is no abnormality in any of the tires 11 of the multiple wheels 10.

[0068] As described above, in the abnormality detection system 1 of this embodiment, the angular velocity of each wheel 10 is calculated from an image captured to include the two-dimensional codes 13 of multiple wheels 10, so that the angular velocity of the wheels 10 can be obtained without using a sensor mounted on the vehicle 2, and an abnormality in the internal pressure of the tire 11 of the vehicle 2 can be detected.

[0069] In this embodiment, the determination result that there is an internal pressure abnormality is stored in association with the code ID information of the two-dimensional code 13 corresponding to the tire 11 identified as having an internal pressure abnormality. Therefore, the tire 11 having an internal pressure abnormality can be immediately identified.

[0070] <Other embodiments> The present disclosure is not limited to the above-described embodiments, and the configuration can be changed, added, or deleted.

[0071] For example, in the above embodiment, the anomaly detection process is executed by the processing circuit 20 of the data processing device 6, but a part or all of the anomaly detection process may be executed by the processing circuit 30 of the server 4. For example, the data processing device 6 may transmit information including the first image and the second image captured by the camera 7 to the server 4. The processing circuit 30 of the server 4 may execute the anomaly detection process based on the image information received from the data processing device 6, etc.

[0072] A part or the whole of the anomaly detection process may be executed by the processing circuit 40 of the information processing terminal 5. For example, the server 4 may store information including the first image and the second image sent from the data processing device 6, and the information processing terminal 5 that has accessed the server 4 may receive the information including the first image and the second image from the server 4 and execute the anomaly detection process. The information processing terminal 5 may receive the information including the first image and the second image from the data processing device 6 and execute the anomaly detection process.

[0073] Two or more of the processing circuit 20 of the data processing device 6, the processing circuit 30 of the server 4, and the processing circuit 40 of the information processing terminal 5 may share and execute the anomaly detection process. For example, the processing circuit 20 of the data processing device 6 may execute the processes from steps S1 to S5, and the processing circuit 30 of the server 4 may receive the angular velocity information obtained in step S5 from the data processing device 6, and execute the process of step S6 based on the angular velocity information.

[0074] For example, the number of wheels provided on the inspection target vehicle 2 does not have to be four. For example, the number of wheels provided on the inspection target vehicle 2 may be six or eight.

[0075] The multiple cameras 7 are preferably positioned so as to simultaneously capture images of the multiple wheels 10 of the vehicle 2 to be inspected. In the above embodiment, the number of cameras 7 provided in the vehicle inspection system 3 and the number of wheels 10 of the vehicle 2 to be inspected may not be the same as each other, and may be different. Furthermore, the vehicle inspection system 3 may be provided with a different number of cameras 7. The number of cameras 7 provided in the vehicle inspection system 3 does not have to be four, and may be, for example, one, two, or six or more. When the vehicle inspection system 3 is provided with two cameras 7, the two cameras 7 are preferably positioned so as to simultaneously capture images of the two front wheels 10 of the wheels 10 of the vehicle 2 to be inspected, respectively.

[0076] An image of one camera 7 may include multiple wheels 10. For example, a six-wheeled truck includes two front wheels and four rear wheels, and the four rear wheels are arranged at a close distance in the front-to-rear direction. Therefore, for example, two rear wheels arranged in a line on one side, either left or right, may be imaged by one camera.

[0077] The anomaly detection system 1 does not need to include the server 4. In this case, the data processing device 6 may directly transmit the judgment result to the information processing terminal 5. Furthermore, the anomaly detection system 1 does not need to include multiple information processing terminals 5. For example, the data processing device 6 may output the judgment result to the user interface 24. The vehicle inspection system 3 may be provided with a separate output device that receives the judgment result from the data processing device 6 and outputs the judgment result or information corresponding to the judgment result. The number of vehicle inspection systems 3 provided in the anomaly detection system 1 does not need to be multiple, and may be just one.

[0078] The determination methods 1, 2, and 3 described in the above embodiments can be modified as appropriate. For example, the limit value L1 of the determination method 1 may be a fixed value or a variable value that changes according to the vehicle-related information. For example, the limit value L2 of the determination method 2 may be a fixed value or a variable value that changes according to the vehicle-related information. For example, the limit value L3 of the determination method 3 may be a fixed value, and in this case, the evaluation value may be a value that is set based on the angular velocity and the vehicle-related information, rather than the angular velocity of the wheel 10 itself.

[0079] In addition, in the above embodiment, the angular velocity of the wheel is calculated using a first image and a second image captured at a predetermined time interval from each other, but the accuracy of calculating the angular velocity of the wheel can be improved by using not only an image set consisting of a plurality of first images and a plurality of second images, but also another image set captured at a predetermined time interval from each other.

[0080] More specifically, in addition to acquiring an image set consisting of a plurality of first images and a plurality of second images in steps S1 and S2, the processing circuit may acquire (N-1) image sets, where N is an integer equal to or greater than 2. Each of the (N-1) image sets is composed of a plurality of k-th images and a plurality of (k+1)-th images captured during the running of the vehicle at a time interval from each other so as to include two-dimensional codes of a plurality of wheels, where k is any integer equal to or greater than 2 and equal to or less than N. In this way, N image sets including an image set consisting of a plurality of first images and a plurality of second images are obtained.

[0081] Such a set of N images can be easily obtained, for example, by capturing a moving image at a predetermined frame rate using the camera 7. In this case, each of the sets of N images includes two consecutive frames among the multiple frames that make up the moving image.

[0082] Furthermore, the processing circuit may calculate, for each image set, a rotational displacement amount of the orientation of the corresponding two-dimensional code in the (k+1)th image relative to the orientation of the corresponding two-dimensional code in the kth image.The processing circuit may then calculate the angular velocity of each wheel by calculating an average value of the calculated N rotational displacement amounts and dividing the average value by the time interval.Alternatively, the processing circuit may use, for calculating the angular velocity, the N rotational displacement amounts excluding values ​​that deviate from the average value by a difference of a predetermined threshold or more.

[0083] As described above, the above embodiment has been described as an example of the technology disclosed in this application. However, the technology in this disclosure is not limited to this, and can be applied to embodiments in which modifications, replacements, additions, omissions, etc. have been made as appropriate. In addition, it is also possible to combine the components described in the above embodiment to create a new embodiment. For example, a part of the configuration or method in one embodiment may be applied to another embodiment, and a part of the configuration in an embodiment can be separated from other configurations in that embodiment and arbitrarily extracted. In addition, among the components described in the attached drawings and detailed description, not only components essential for solving the problem but also components that are not essential for solving the problem are included in order to illustrate the technology. Two blocks shown in order in the flowchart can be executed simultaneously or in reverse order depending on the case.

[0084] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general purpose processors, special purpose processors, integrated circuits, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. Processors are considered processing circuits or circuits because they include transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the recited functions or hardware that is programmed to perform the recited functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the recited functions. Where the hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0085] Each of the following aspects is a disclosure of a preferred embodiment.

[0086] [Aspect 1] An abnormality detection system for detecting an abnormality in an internal pressure of a tire of a vehicle including a tire, a tire wheel on which the tire is mounted, and a plurality of wheels including a two-dimensional code disposed on a side surface of the tire wheel, the system comprising: The anomaly detection system includes a processing circuit; The processing circuitry includes: acquiring a plurality of first images captured while the vehicle is traveling, the first images including the two-dimensional codes of the plurality of wheels; acquiring a plurality of second images captured during the running of the vehicle at a predetermined time interval from the capture of the first image so as to include the two-dimensional codes of the plurality of wheels; calculating, for each wheel, an amount of rotational displacement of a direction of the corresponding two-dimensional code in the second image relative to a direction of the corresponding two-dimensional code in the first image; calculating an angular velocity of each of the wheels based on the corresponding rotational displacement amount and the time interval for each of the wheels; determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels based on the angular velocities of the plurality of wheels; The anomaly detection system is configured to:

[0087] According to the above configuration, it is possible to obtain the angular velocity of the wheels and detect an abnormality in the internal pressure of the vehicle tires without using a sensor mounted on the vehicle.

[0088] [Aspect 2] Determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels includes identifying which tire of the plurality of wheels has an abnormal internal pressure; The anomaly detection system of aspect 1, wherein the processing circuit is further configured to, after identifying the tire having an internal pressure abnormality, store the determination result that there is an internal pressure abnormality in association with the code ID information of the two-dimensional code corresponding to the tire identified as having an internal pressure abnormality.

[0089] According to the above configuration, since the determination result that there is an abnormality in the internal pressure is associated with the code ID information, it is possible to immediately identify the tire having the abnormality in the internal pressure.

[0090] [Aspect 3] the plurality of wheels includes a first wheel and a second wheel; Determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels includes: setting an evaluation value that changes according to a change in the difference between the angular velocity of the first wheel and the angular velocity of the second wheel; determining whether the evaluation value satisfies an abnormality determination condition; determining that an internal pressure abnormality exists in the tire of the first wheel or the tire of the second wheel when it is determined that the evaluation value satisfies the abnormality determination condition; 3. The anomaly detection system of claim 1 or 2,

[0091] According to the above configuration, the presence of a tire with abnormal internal pressure can be determined in a simple manner by utilizing the difference in angular velocity between a wheel including a tire with no abnormal internal pressure and a wheel including a tire with abnormal internal pressure.

[0092] [Aspect 4] Determining whether or not a tire having an abnormal internal pressure is present among the plurality of tires includes Determining whether or not an evaluation value, which is the angular velocity itself or a value based on the angular velocity, satisfies an abnormality determination condition; when it is determined that the evaluation value satisfies the abnormality determination condition, it is determined that the tire corresponding to the evaluation value has an internal pressure abnormality; 4. The anomaly detection system according to any one of aspects 1 to 3, comprising:

[0093] According to the above configuration, an internal pressure abnormality in the tire of a wheel is determined using an evaluation value corresponding to the angular velocity of each wheel, so that the tire having the internal pressure abnormality can be easily identified.

[0094] [Aspect 5] The abnormality detection system of aspect 4, wherein determining whether the evaluation value satisfies the abnormality judgment condition includes setting the evaluation value or the abnormality judgment condition using an average value of the angular velocities of the multiple wheels.

[0095] According to the above configuration, it is possible to grasp the angular velocity of a wheel that significantly deviates from the average value of the angular velocities of a plurality of wheels, so that a tire having an abnormal internal pressure can be easily identified.

[0096] [Aspect 6] The processing circuitry includes: obtaining vehicle-related information indicative of a characteristic of the vehicle, a state of the vehicle, or a combination of the characteristic of the vehicle and the state of the vehicle; setting the evaluation value, the abnormality determination condition, or both the evaluation value and the abnormality determination condition according to the acquired vehicle-related information; 6. The anomaly detection system of claim 4 or 5, further configured to:

[0097] According to the above configuration, the evaluation value or abnormality judgment conditions are set according to the characteristics and condition of the vehicle, so that a judgment appropriate to the characteristics and condition of the vehicle can be made, and the presence or absence of an abnormality in the tire internal pressure can be accurately determined.

[0098] [Aspect 7] the vehicle-related information includes size information indicating a size of the wheels equipped on the vehicle, The acquiring of the vehicle-related information includes: Reading the recorded information of the two-dimensional code; 7. The anomaly detection system of claim 6, further comprising obtaining the size information included in or associated with the record information.

[0099] According to the above-mentioned configuration, the evaluation value or abnormality determination condition can be set according to the size of the wheel. Also, since the size of the wheel can be determined by reading the information recorded in the two-dimensional code, it is easy to obtain the size information.

[0100] [Aspect 8] the vehicle-related information includes speed information indicating a traveling speed of the vehicle; An abnormality detection system as described in aspect 6 or 7, wherein setting the evaluation value or the abnormality judgment condition includes setting the abnormality judgment condition corresponding to the acquired vehicle-related information in accordance with a predetermined correspondence relationship between the vehicle's traveling speed and the abnormality judgment condition.

[0101] According to the above configuration, the abnormality determination condition suitable for the traveling speed of the vehicle can be set, and abnormalities in the internal pressure of the tire can be detected with high accuracy.

[0102] [Aspect 9] A second two-dimensional code is arranged on a side surface of each of the tire wheels in addition to the first two-dimensional code, which is the two-dimensional code; Both the first image and the second image include the second two-dimensional code; The processing circuitry includes: calculating, for each wheel, a second rotational displacement amount of an orientation of the second two-dimensional code in the second image relative to an orientation of the second two-dimensional code in the first image; calculating a second angular velocity of each of the wheels based on the corresponding second rotational displacement amount and the time interval for each of the wheels; determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels based on the second angular velocities of the plurality of wheels; 9. The anomaly detection system of any one of aspects 1 to 8, further configured to:

[0103] According to the above configuration, for example, when both the first two-dimensional code and the second two-dimensional code are recognized, the tire internal pressure abnormality can be determined using both the first angular velocity obtained based on the first two-dimensional code and the second angular velocity obtained based on the second two-dimensional code, thereby improving the determination accuracy. Also, for example, the first two-dimensional code may not be image-recognized due to some factor such as dirt or scratches. Even in such a case, the tire internal pressure abnormality can be determined using the image-recognizable two-dimensional code out of the first two-dimensional code and the second two-dimensional code.

[0104] [Aspect 10] The processing circuitry includes: acquiring (N-1) image sets other than the image set composed of the plurality of first images and the plurality of second images, where N is an integer equal to or greater than 2, and the image sets are composed of a plurality of k-th images and a plurality of (k+1)-th images captured while the vehicle is traveling at the time intervals from each other so as to include the two-dimensional codes of the plurality of wheels, where k is an integer equal to or greater than 2 and equal to or less than N; calculating, for each of the image sets, an amount of rotational displacement of the orientation of the corresponding two-dimensional code of the (k+1)th image relative to the orientation of the corresponding two-dimensional code of the kth image; and further configured to: 10. The anomaly detection system according to any one of aspects 1 to 9, wherein calculating the angular velocity of each of the wheels comprises calculating the angular velocity of each of the wheels based on the calculated N rotational displacement amounts.

[0105] According to the above configuration, the angular velocity of the wheel can be calculated with high accuracy using a plurality of image sets, and as a result, the accuracy of abnormality determination can be improved.

[0106] [Aspect 11] 1. An abnormality detection method for detecting an abnormality in an internal pressure of a tire of a vehicle including a tire, a tire wheel on which the tire is mounted, and a plurality of wheels including a two-dimensional code disposed on a side surface of the tire wheel, the method comprising: acquiring a plurality of first images captured while the vehicle is traveling, the first images including the two-dimensional codes of the plurality of wheels; acquiring a plurality of second images captured during the running of the vehicle at a predetermined time interval from the capture of the first image so as to include the two-dimensional codes of the plurality of wheels; calculating, for each wheel, an amount of rotational displacement of a direction of the corresponding two-dimensional code in the second image relative to a direction of the corresponding two-dimensional code in the first image; calculating an angular velocity of each of the wheels based on the corresponding rotational displacement amount and the time interval for each of the wheels; determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels based on the angular velocities of the plurality of wheels; The anomaly detection method includes:

[0107] According to the above method, the wheel angular velocity can be obtained without using a sensor mounted on the vehicle, and an abnormality in the internal pressure of the vehicle's tires can be detected.

[0108] [Aspect 12] An anomaly detection program that causes at least one processor to execute the anomaly detection method described in aspect 11. [Explanation of symbols]

[0109] 1: Anomaly detection system 2: Vehicle 4: Server 5: Information processing terminal 6: Data processing device 7: Camera 10: Wheels 11: Tires 12: Tires and wheels 13: 2D code 20: Processing circuit P1: First image P2: Second image

Claims

1. An abnormality detection system for detecting an abnormality in an internal pressure of a tire of a vehicle including a tire, a tire wheel on which the tire is mounted, and a plurality of wheels including a two-dimensional code disposed on a side surface of the tire wheel, the system comprising: The anomaly detection system includes a processing circuit; The processing circuitry includes: acquiring a plurality of first images captured while the vehicle is traveling, the first images including the two-dimensional codes of the plurality of wheels; acquiring a plurality of second images captured while the vehicle is traveling at a predetermined time interval from the capture of the first image so as to include the two-dimensional codes of the plurality of wheels; calculating, for each wheel, an amount of rotational displacement of a direction of the corresponding two-dimensional code in the second image relative to a direction of the corresponding two-dimensional code in the first image; calculating an angular velocity of each of the wheels based on the corresponding rotational displacement amount and the time interval for each of the wheels; determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels based on the angular velocities of the plurality of wheels; The anomaly detection system is configured to:

2. Determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels includes identifying which tire of the plurality of wheels has an abnormal internal pressure; 2. The abnormality detection system according to claim 1, wherein the processing circuit is further configured to, after identifying the tire having an internal pressure abnormality, store a determination result that there is an internal pressure abnormality in association with code ID information of the two-dimensional code corresponding to the tire identified as having an internal pressure abnormality.

3. the plurality of wheels includes a first wheel and a second wheel; Determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels includes: setting an evaluation value that changes according to a change in the difference between the angular velocity of the first wheel and the angular velocity of the second wheel; determining whether the evaluation value satisfies an abnormality determination condition; when it is determined that the evaluation value satisfies the abnormality determination condition, it is determined that an internal pressure abnormality exists in the tire of the first wheel or the tire of the second wheel; The anomaly detection system according to claim 1 or 2, comprising:

4. Determining whether or not a tire having an abnormal internal pressure is present among the plurality of tires includes Determining whether or not an evaluation value, which is the angular velocity itself or a value based on the angular velocity, satisfies an abnormality determination condition; when it is determined that the evaluation value satisfies the abnormality determination condition, it is determined that the tire corresponding to the evaluation value has an internal pressure abnormality; The anomaly detection system according to claim 1 or 2, comprising:

5. 5. The abnormality detection system according to claim 4, wherein determining whether the evaluation value satisfies the abnormality determination condition includes setting the evaluation value or the abnormality determination condition using an average value of the angular velocities of the plurality of wheels.

6. The processing circuitry includes: obtaining vehicle-related information indicative of a characteristic of the vehicle, a state of the vehicle, or a combination of the characteristic of the vehicle and the state of the vehicle; setting the evaluation value, the abnormality determination condition, or both the evaluation value and the abnormality determination condition according to the acquired vehicle-related information; The anomaly detection system of claim 4 , further configured to:

7. the vehicle-related information includes size information indicating a size of the wheels equipped on the vehicle, The acquiring of the vehicle-related information includes: Reading the recorded information of the two-dimensional code; The anomaly detection system of claim 6 , further comprising obtaining the size information included in or associated with the record information.

8. the vehicle-related information includes speed information indicating a traveling speed of the vehicle; 7. The abnormality detection system according to claim 6, wherein setting the evaluation value or the abnormality judgment condition includes setting the abnormality judgment condition corresponding to the acquired vehicle-related information in accordance with a predetermined correspondence relationship between the vehicle's traveling speed and the abnormality judgment condition.

9. A second two-dimensional code is arranged on a side surface of each of the tire wheels in addition to the first two-dimensional code, which is the two-dimensional code; Both the first image and the second image include the second two-dimensional code; The processing circuitry includes: calculating, for each wheel, a second rotational displacement amount of an orientation of the second two-dimensional code in the second image relative to an orientation of the second two-dimensional code in the first image; calculating a second angular velocity of each of the wheels based on the corresponding second rotational displacement amount and the time interval for each of the wheels; determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels based on the second angular velocities of the plurality of wheels; The anomaly detection system according to claim 1 or 2, further configured to perform the following:

10. The processing circuitry includes: acquiring (N-1) image sets other than an image set composed of the plurality of first images and the plurality of second images, where N is an integer equal to or greater than 2, and the image sets are composed of a plurality of k-th images and a plurality of (k+1)-th images captured while the vehicle is traveling at the time interval from each other so as to include the two-dimensional codes of the plurality of wheels, where k is an integer equal to or greater than 2 and equal to or less than N; calculating, for each of the image sets, an amount of rotational displacement of the orientation of the corresponding two-dimensional code of the (k+1)th image relative to the orientation of the corresponding two-dimensional code of the kth image; and further configured to:

3. The abnormality detection system according to claim 1, wherein calculating the angular velocity of each of the wheels comprises calculating the angular velocity of each of the wheels based on the calculated N rotational displacement amounts.

11. 1. An abnormality detection method for detecting an abnormality in an internal pressure of a tire of a vehicle including a tire, a tire wheel on which the tire is mounted, and a plurality of wheels including a two-dimensional code disposed on a side surface of the tire wheel, the method comprising: acquiring a plurality of first images captured while the vehicle is traveling, the first images including the two-dimensional codes of the plurality of wheels; acquiring a plurality of second images captured while the vehicle is traveling at a predetermined time interval from the capture of the first image so as to include the two-dimensional codes of the plurality of wheels; calculating, for each wheel, an amount of rotational displacement of a direction of the corresponding two-dimensional code in the second image relative to a direction of the corresponding two-dimensional code in the first image; calculating an angular velocity of each of the wheels based on the corresponding rotational displacement amount and the time interval for each of the wheels; determining whether or not a tire having an abnormal internal pressure is present among the tires of the plurality of wheels based on the angular velocities of the plurality of wheels; The anomaly detection method includes:

12. An anomaly detection program that causes at least one processor to execute the anomaly detection method according to claim 11.

Images