JP7801774B2 - Tracking system, and construction machine attachment status detection system, victim search system, and immovable object status detection system using the tracking system - Google Patents

Description

The present invention relates to a tracking system that autonomously measures changes in at least one of the position, orientation, and moving speed of a tracked object and autonomously communicates the changes to an external system.
Examples of applications include systems for detecting the condition of construction machinery attachments, which are movable and replaceable parts of construction machinery; systems for detecting the condition of agricultural machinery; systems for searching for lost persons; and systems for detecting the condition of immovable objects such as rocks and embankments.

In recent years, data communication has not only been limited to computer-to-computer data communication. IoT (Internet of Things), a technology in which various objects are equipped with communication modules and transmit data to control systems via networks, is becoming increasingly widespread. Low-power wide-area data transmission (LPWA) communication is gaining attention as a communication method. As shown in Figure 8, various communication standards exist. While general computer-to-computer communication standards and mobile phone network standards (e.g., Wi-Fi, 3G, 4G, and 5G) aim for high-speed communication and are excessive for IoT. LPWA targets IoT and aims to reduce costs by limiting specifications to relatively low levels. While LPWA's transmission speed is significantly slower than wired LAN or wireless LAN, it has many advantages. For example, it can transmit over a wide area, has a narrow frequency bandwidth, and consumes very little power. It is said to be suitable for sensor networks, which require small data volumes and transmit multiple intermittent transmissions.

Communication standards based on LPWA include communication methods that use frequency bands that do not require a license (unlicensed bands) and communication methods that use frequency bands that require a license (licensed bands). Examples of the former include Sigfox (sub-GHz communication frequency band, maximum communication speed of 100 bps, communication distance of approximately several tens of kilometers), LoRaWAN (sub-GHz communication frequency band, maximum communication speed of 250 kbps, communication distance of approximately 10 km), ELTRES, and ZETA. Examples of the latter include LTE-M and NB-IoT.
In particular, Sigfox has been attracting attention in recent years. Sigfox is a communications method developed by the French company UnaBiz SAS. Although it is a low-speed communications standard with a maximum speed of around 100 bps, it can communicate over long distances of several tens of kilometers, and its low cost and low power consumption make it a communications method suitable for global IoT networks.
Known examples include a construction machinery work management system disclosed in Patent Document 1 (JP 2023-61535 A) shown in FIG. 9 and a wireless communication terminal disclosed in Patent Document 2 (JP 2009-44309 A) shown in FIG. 10 .

Japanese Patent Application Laid-Open No. 2020-136985 JP 2009-044309 A

The communication standard based on LPWA in the above-mentioned conventional technology is a communication standard suitable for IoT devices, but although it is basically excellent for application to fixed objects, it is not suitable for application to objects that can move relatively quickly.
The first problem is that with the conventional LPWA, it is difficult to retry data that has failed to be transmitted or received. As mentioned above, even small amounts of data can fail to be transmitted or received with LPWA. However, while the general solution to reduce data transmission and reception failures requires high specifications, those who build and operate LPWA systems have placed emphasis on cost reduction and have not taken measures to increase specifications, and have continued to operate with missing data even if several data transmissions and receptions fail during intermittent data transmissions.

The second problem is that with conventional LPWA technology, even small volumes of data require a long transmission and reception time, which can lead to high error rates on the receiving side. The above-mentioned LPWA-based communication standard has a slow communication speed, and it takes a long time to send and receive a single data transmission. For example, Sigfox requires approximately 7 to 8 seconds. This poses the problem of a high reception error rate on the receiving side when the moving speed of a moving object is fast.

The third problem is that conventional LPWA technology is narrowband wireless communication, making it vulnerable to frequency shifts caused by Doppler shifts. The communication standard based on the above-mentioned LPWA is narrowband wireless communication; for example, in the case of Sigfox, the communication frequency is in the sub-GHz band, making it a narrow band. Therefore, if a moving object is moving quickly, frequency shifts due to Doppler shifts can occur in communication, which could result in communication being interrupted.

On the other hand, however, communication standards based on LPWA have various possibilities and potential.
The present inventors have realized that by implementing a low-cost measure in a communication module based on LPWA, it is possible to retry data that has failed in transmission and reception.
Furthermore, the inventors have discovered that by incorporating various sensor modules, the technology can be applied to objects in specific environments or conditions, such as objects that move but then return to a fixed position, or objects (objects, human bodies) that move relatively slowly. They have also discovered the possibility of application to detecting the movement of objects that would not normally move, and to searching for mountain climbers or victims lost at sea.

The present invention was made in consideration of the above circumstances, and aims to provide a communications device and method that enables retry of data transmission and reception that has failed in an LPWA-based communications module, and that can be applied to objects in specific environments or conditions and incorporated into applications that handle those objects.

In order to achieve the above object, a tracking system of the present invention is a tracking system that autonomously measures changes in at least one of a position, an attitude, and a moving speed of a tracked object and autonomously communicates the changes to an external system, and includes a GPS module that acquires position data of the tracked object at a first predetermined time interval, a sensor module that measures changes in at least one of acceleration data, magnetic change data, illuminance change data, temperature change data, and time data occurring in the tracked object at a second predetermined time interval, a central control unit, a memory device, and a specific communication device, wherein the GPS module includes GPS data temporary storage means that writes measurement results of the position data of the tracked object obtained at the first predetermined time interval into the memory device, and the sensor module includes sensor data temporary storage means that writes sensor data of the tracked object obtained at the second predetermined time interval into the memory device, the acceleration data, the magnetic change data, the illuminance change data, the temperature change data, and the time data, and the specific communication module is a Low Power Wideband Tracking (LWW) tracking system. and a communication control means for transmitting the GPS data and the sensor data temporarily stored in the memory device to the external system via the external specific communication antenna at a third predetermined time interval if the tracking system is within a communication area of the external specific communication antenna.
An example of the specific communication module is a communication device for a low power wide area network that enables power-saving and long-distance wireless communication.

With the above configuration, a simple device configuration consisting of an LPWA communication module, GPS module, sensor module, central control unit, memory unit, GPS data temporary storage means, sensor data temporary storage means, and communication control means can retry data transmission and reception that has failed. Using various sensors and the data transmission and reception retry function, it can be applied to objects in specific environments or conditions, or incorporated into applications that handle those objects.

Next, in the above configuration, if the specific communication device is unable to communicate data via the external specific communication antenna after a third predetermined time interval has elapsed, it is preferable that the specific communication device continues to temporarily store the untransmitted GPS data and sensor data written in the memory device, and after the next third predetermined time interval has elapsed, perform data communication of the untransmitted GPS data and sensor data and the GPS data and sensor data that have been newly written until the next third predetermined time interval.
Since a state in which data transmission and reception using the LPWA communication module is not possible may continue for some time, it is preferable to retry data transmission and reception multiple times at predetermined intervals.

Next, in order to ensure the retry of the above-mentioned data transmission and reception, it is preferable that the GPS module or the central control device assigns a GPS data serial number to the GPS data at each of the first predetermined time intervals required for measurement and writes the data to the memory device, and the sensor module or the central control device assigns a sensor data serial number to the sensor data at each of the second predetermined time intervals required for measurement and writes the data to the memory device, and when performing the data communication using the specific communication means, the GPS data with the GPS data serial number and the sensor data with the sensor data serial number are transmitted.
With the above configuration, new data is accumulated while the data that has not yet been transmitted is continued to be temporarily stored, and it becomes easier to manage data transmission so that no data is missed.

For example, in the process of retrying data transmission and reception, it is preferable that the specific communication device or the central control device accepts a retransmission request for data specifying the GPS data serial number or the sensor data serial number from the external system via the external specific communication antenna, and retransmits the GPS data with the GPS data serial number specified in the retransmission request, and the sensor data with the specified sensor data serial number.
With the above configuration, an external center with relatively ample computer resources can use the GPS data serial number and the sensor data serial number as clues to determine which data has been received and which data has not been received, and can request that the data be resent by specifying the data that has not been received, thereby making data transmission and reception between the tracking system and the external center more efficient.

Next, there are a number of possible applications to which the tracking system of the present invention can be applied.
For example, there is a construction machinery attachment status detection system in which the tracking object is a construction machinery attachment, which is a moving part and a replaceable part of the construction machinery, the sensor module is capable of measuring the acceleration data and the time data generated in the tracking object, and an external system that receives the sensor data communication can detect the time when the construction machinery attachment is in use and the time when it is not in use.

For example, there is an agricultural machinery status detection system in which the tracking target is agricultural machinery, the sensor module is capable of measuring the acceleration data and time data generated by the tracking target, and an external system that receives the sensor data can detect the position of the agricultural machinery, as well as the time it is in use and the time it is not in use.

Also, for example, there is a missing person search system in which the person to be tracked is a mountain climber or a sailor, and the person is wearing a tracking system according to the present invention, and an external system that receives the GPS data can detect the position of the person to be tracked.
In this victim search system, the external specific communication antenna can be mounted on a flyable drone. When the victim is within the communication area of the specific communication antenna mounted on the drone, the specific communication means can obtain information about the victim's location through data communication from a tracking system worn by the victim.

In addition, for example, there is an immovable object status detection system in which the tracking target is a rock, embankment, forest, road, bridge, or tunnel, which is normally an immovable object, and the tracking system of the present invention is attached to the immovable object, and the sensor module is capable of measuring at least the acceleration data generated in the tracking target, and an external system that receives data communication of the GPS data and the sensor data can detect the movement or signs of movement of the immovable object.

According to the tracking system of the present invention, a simple device configuration including an LPWA communication module, a GPS module, a sensor module, a central control unit, a memory unit, a GPS data temporary storage means, a sensor data temporary storage means, and a communication control means can retry data transmission that has failed. While continuing to temporarily store unsent data, new data can be accumulated, and data transmission can be managed to ensure that no data is missed.
Using various sensors and data transmission and reception retry functions, it can be applied to objects in specific environments or conditions, and can be incorporated into applications that handle those objects.

1 is a diagram schematically illustrating an example of the configuration of a tracking system 100 according to the present invention. 10 is a flowchart showing a normal procedure routine. 10 is a flowchart showing the flow of processing for making a request to the tracking system 100 for retransmission of data that needs to be retransmitted, together with the serial number. 10 is a flowchart showing a processing flow when an operation is assumed in which ACK/NCK is exchanged between the tracking system 100 and the external system 300. FIG. 4 is a simplified diagram illustrating a state detection system 400a for a construction machine attachment. FIG. 4 is a diagram simply showing the configuration of a lost person search system 400c. FIG. 4 is a diagram briefly explaining the configuration of an immobile state detection system 400d. FIG. 1 is a diagram illustrating various communication standards from an overview. FIG. 1 is a diagram showing a construction machine work management system disclosed in a conventional patent document 1 (JP 2023-61535 A). FIG. 1 is a diagram showing a conventional wireless communication terminal disclosed in Patent Document 2 (JP 2009-44309 A).

The following describes embodiments of the tracking system of the present invention and various systems to which the tracking system is applied, with reference to the drawings. However, it goes without saying that the scope of the present invention is not limited to the specific uses, shapes, numbers, etc. shown in the following embodiments.

1 shows an example of a tracking system 100 according to a first embodiment of the present invention.
The tracking system 100 of the present invention autonomously measures changes in at least one of the position, orientation, and moving speed of a tracked object, and autonomously communicates the changes to an external system.
1 is a diagram showing a schematic configuration example of a tracking system 100 of the present invention. The internal configuration of the tracking system 100 is shown as a schematic block, and the electrical circuits and detailed components are not shown. It is assumed that the tracking system 100 is formed on a substrate, and the substrate is housed in a housing together with a battery, but a description thereof will be omitted here.

As shown in Figure 1, in the configuration example of this first embodiment, the tracking system 100 is configured to include a GPS module 110, a sensor module 120, a central control unit 130, a memory unit 140, and a specific communication device 150. Figure 1 also shows a tracked object 200, an external system 300, and an external specific communication antenna 310.

The GPS module 110 is a module that acquires position data of the tracked object 200 at a first predetermined time interval.
GPS is a global positioning system that uses signals received from several GPS satellites in the sky to determine the current location, and the GPS module 110 is a module equipped with the function of receiving signals from these GPS satellites. In recent years, the GPS module 110 that receives signals from GPS satellites has become smaller and smaller, measuring just a few centimeters.
The GPS module 110 outputs the measurement results of the position data of the tracked object obtained at a first predetermined time interval to the central control unit 130, and the central control unit 130 is equipped with a GPS data temporary storage means 131, which writes the GPS data to the memory device 140.
The first predetermined time interval is not limited, but can be freely set to, for example, several minutes, several hours, etc. In this case, if it is set to, for example, 20 minutes, the GPS data temporary storage means 131 writes the location information acquired by the GPS module 110 into the memory device 140 once every 20 minutes.

The sensor module 120 measures data of the sensing target occurring in the tracked target 200 at a second predetermined time interval. The sensing data may include, for example, acceleration data, magnetic change data, illuminance change data, temperature change data, and time data.

Sensors that sense acceleration data are known as gyro sensors, and in recent years these gyro sensors have become increasingly miniaturized, measuring just a few centimeters in size.

Sensors that sense magnetic change data are known as magnetic sensors, and generally convert the magnitude and amount of change in a magnetic field into an electrical signal. Magnetic sensors include coils, reed switches, Hall elements, MR sensor elements, and superconducting quantum interference devices. In recent years, magnetic sensors have become increasingly miniaturized, ranging in size from a few millimeters to a few centimeters.

Sensors that sense illuminance change data are provided as so-called illuminance sensors, which sense the ambient brightness. They have a structure that integrates a photodiode and a transistor, and convert light incident on the light-receiving element into an electric current to detect brightness. Illuminance sensors have optical characteristics similar to human visual sensitivity and can capture changes in the light environment at the sensor location, and can detect, for example, whether the tracked object 200 is exposed to sunlight outdoors or hidden in the shade indoors.

Sensors that sense temperature change data are provided as so-called temperature sensors, which sense the ambient temperature. They are available in contact and non-contact types, but this invention is not limited to these, and either type can be installed depending on the purpose and application. Examples include temperature sensors that utilize the temperature characteristics of transistors or diodes, thermistor-type temperature sensors that utilize the resistance-temperature characteristics of semiconductors, temperature sensors that utilize the thermoelectric power (Seebeck effect) generated in thermocouples, and radiation temperature sensors used in thermography, which output temperature changes in a sensor element exposed to infrared light as an electrical signal using resistance changes, thermoelectric power, or the pyroelectric effect.
In recent years, temperature sensors have become increasingly miniaturized, measuring just a few centimeters.

Time data can be obtained using a timer, which has become increasingly miniaturized in recent years and is now integrated into chips.

The sensor module 120 outputs sensor data obtained at a second predetermined time interval as a result of sensing the tracked object 200, such as acceleration data, magnetic change data, illuminance change data, temperature change data, and time data, or a combination thereof, to the central control unit 130. The central control unit 130 is equipped with a sensor data temporary storage means 132, which writes the sensor data to the memory device 140.

The second predetermined time interval at which the sensor module 120 performs sensing is not limited to a specific time interval, and can be set freely to, for example, several minutes, several hours, etc. In this example, if the time interval is set to, for example, 20 minutes, the sensor data acquired by the sensor module 120 is written to the memory device 140 by the sensor data temporary storage means 132 once every 20 minutes.
In this example, the first predetermined time interval, which is the interval at which the GPS data temporary storage means 131 acquires position data from the GPS module 110 and writes it to the memory device 140, and the second predetermined time interval, which is the interval at which the sensor data sensed by the sensor module 120 is acquired and the sensor data temporary storage means 132 writes it to the memory device 140, are the same, but they may be the same time interval or different time intervals. Here, they are assumed to be the same time interval.

The central control unit 130 is a microprocessor-based controller IC, and may be a CPU installed in a general personal computer, but the CPU of a general personal computer is overkill, so the central control unit 130 installed in the tracking system 100 of the present invention may be of low specification with a slow processing speed and limited processing capacity. It is better if it is miniaturized, and it is preferable that it is made into a chip of about a few centimeters.
In this configuration example, the central control device 130 includes a GPS data temporary storage means 131 and a sensor data temporary storage means 132 .
The GPS data temporary storage means 131 writes the measurement results of the position data of the tracking target obtained at a first predetermined time interval into the memory device 140 .
The sensor data temporary storage means 132 writes the measurement results of the sensor data obtained by sensing the tracking target at the second predetermined time interval into the memory device 140 .
The GPS data temporary storage means 131 and the sensor data temporary storage means 132 may be provided as programs that cause the central control unit 130 to function as such, and may be stored in an internal memory or an external memory device 140.

The memory device 140 may be a general-purpose memory device, and the memory capacity may be small.
Although an internal memory built into the central control unit 130 may be used, in this configuration example, an external memory is installed to ensure a certain amount of capacity.

The specific communication device 150 includes a specific communication module 151 and a communication control means 152 .
The communication module 151 is a communication module capable of transmitting and receiving data in accordance with the LPWA (Low Power Wide Area) communication standard.
There are several types of LPWA communication standards, such as Sigfox, LoRaWAN, ELTRES, ZETA, LTE-M, and NB-IoT, and the present invention is not limited to any of these, but here we will use, for example, a communication module 151 that uses Sigfox.
In other words, in this example, the communication module 151 of the specific communication device 150 conforms to the Sigfox communication standard, and the communication capability of the tracking system 100 utilizes the sub-GHz communication frequency band, has a maximum communication speed of 100 bps, and has a communication area of several tens of kilometers.

When the specific communication device 150 is within the communication area of the external specific communication antenna 310, the communication control means 152 transmits the GPS data and sensor data temporarily stored in the memory device 140 to the external system 300 via the external specific communication antenna 310 at a third predetermined time interval.

The third predetermined time interval is the interval at which the specific communication device 150 executes data communication of the GPS data and sensor data temporarily stored in the memory device 140 to the external system 300. The third predetermined time interval is not limited to a specific interval and can be set freely, for example, to several minutes or several hours. Here, the third predetermined time interval is set to, for example, 20 minutes. In other words, the specific communication device 150 communicates the GPS data and sensor data written in the memory device 140 to the external system 300 once every 20 minutes.
In this example, the third predetermined time interval at which the specific communication device 150 executes data communication of the GPS data and sensor data temporarily stored in the memory device 140 is the same as the first predetermined time interval at which the GPS module acquires position data and writes it to the memory device 140, and the second predetermined time interval at which the sensor module 120 acquires sensed sensor data and writes it to the memory device 140, but they may be the same time interval or different time intervals. Here, they are assumed to be the same time intervals.
The above is the description of the configuration of the tracking system 100.

Next, the external system 300 and the external specific communication antenna 310 will also be described.
The external specific communication antenna 310 is an antenna capable of transmitting and receiving data at a specific frequency with the communication module 151 of the specific communication device 150. Here, for example, if the communication module 151 conforms to the Sigfox communication standard, the external specific communication antenna 310 may be an antenna capable of receiving Sigfox communications (communication frequency sub-GHz band).
The external specific communication antenna 310 may be fixed to a land or a building, or may be mounted on a mobile object.
The external system 300 may be capable of communicating via an external specific communication antenna 310, or may be capable of receiving data transfer from a center side or relay system as envisioned in the Sigfox communication standard. Note that the external system 300 may be capable of relaying transmitted and received data between a plurality of external specific communication antennas 310 from the external specific communication antenna 310 to the Sigfox center system or relay system.

The basic flow of data communication of GPS data and sensor data obtained from the tracked object 200 using the tracking system 100 of the present invention will be described below.
In actual operation, there are various variations depending on the tracking target 200 and operation, but these will be explained in the second embodiment and onwards, and here the basic flow will be explained.

As a preparation, the tracking system 100 of the present invention is attached to the tracked object 200.
Depending on the type of the tracking target 200, it may be attached to the tracking target 200, wrapped around the tracking target 200, mounted inside the housing of the tracking target 200, or stored in the clothing or life jacket of the human body that is the tracking target 200. It is preferable to ensure that the battery or cell has sufficient capacity.
The normal procedure basically involves repeating normal procedure 1 to normal procedure 11 shown in FIG.

The first predetermined time interval and the second predetermined time interval may be different time intervals or may be the same time interval. The third predetermined time interval is a common multiple of the first predetermined time interval and the second predetermined time interval. That is, if the first predetermined time interval, the second predetermined time interval, and the third predetermined time interval are 15 minutes, 10 minutes, and 30 minutes, respectively, then over the course of 30 minutes, two sets of GPS data are stored in memory device 140, and three sets of sensor data are stored in memory device 140. Then, the two sets of GPS data and three sets of sensor data are transmitted from memory device 140 by specific communication device 150 once every 30 minutes.
In the flowchart of Figure 2, normal procedures 1 to 5 for the GPS module 110, which are repeated at a first predetermined time interval (e.g., 15 minutes), and normal procedures 6 to 10 for the sensor module 120, which are repeated at a second predetermined time interval (e.g., 10 minutes), are independent of each other, and normal procedure 11 is executed after a third predetermined time interval (e.g., 30 minutes) has elapsed.

[Normal Procedure 0: S0]
After the most recent normal procedure 11 is completed, the time elapsed is cleared to zero.

[Normal procedure 1: S1]
At a first predetermined time interval (for example, 15 minutes), the GPS module 110 acquires the position data of the tracked object 200 .

[Normal procedure 2: S2]
The GPS module 110 outputs the position data of the tracked object 200 acquired in step 1 to the central control unit 130 .

[Normal Procedure 3: S3]
The GPS data temporary storage means 131 writes the position data into the memory device 140 for temporary storage.

[Normal procedure 4: S4]
The central control unit 130 counts whether the first predetermined time has elapsed, and if the first predetermined time has not elapsed (step S4: N), it waits for the time, and if the first predetermined time has elapsed (step S4: Y), it proceeds to normal procedure 5.

[Normal Procedure 5: S5]
The central control unit 130 counts whether a third predetermined time (e.g., 30 minutes) has elapsed, and if the third predetermined time has not elapsed (step S5: N), it returns to normal procedure 1 and acquires the next GPS data, and if the third predetermined time has elapsed (step S5: Y), it proceeds to normal procedure 11.

[Normal Procedure 6: S6]
At a second predetermined time interval (e.g., 10 minutes), the sensor module 120 measures changes occurring in the tracked object 200. The sensing data may include acceleration data, magnetic change data, illuminance change data, temperature change data, time data, etc. Depending on the application, any one type of data may be acquired independently, or multiple types of data may be acquired in combination.

[Normal procedure 7: S7]
The sensor module 120 outputs the sensing data of the tracked object 200 acquired in step 3 to the central control unit 130 .

[Normal Procedure 8: S8]
The sensor data temporary storage means 132 of the central control unit 130 writes the sensing data relating to the tracked object 200 acquired in step 7 into the memory unit 140 and temporarily stores it.

[Normal Procedure 9: S9]
The central control unit 130 counts whether the first predetermined time has elapsed, and if the second predetermined time has not elapsed (step S9: N), it waits, and if the second predetermined time has elapsed (step S9: Y), it proceeds to normal procedure 10.

[Normal Procedure 10: S10]
The central control device 130 counts whether a third predetermined time (e.g., 30 minutes) has elapsed, and if the third predetermined time has not elapsed (step S10: N), returns to normal procedure 6 and executes acquisition of the next sensor data, and if the third predetermined time has elapsed (step S10: Y), proceeds to normal procedure 11. Note that the third predetermined time is the same time interval for the GPS data acquisition flow of normal procedures 1 to 5 and the sensor data acquisition flow of normal procedures 6 to 10, so the timing of transition from normal procedure 5 to normal procedure 11 and the timing of transition from normal procedure 10 to normal procedure 11 are simultaneous.

[Normal Procedure 11: S11]
At a third predetermined time interval (e.g., 30 minutes), the specific communication device 150, under the control of the communication control means 152, uses the specific communication module 151 to transmit data communication of GPS data and sensor data temporarily stored in the memory device 140 to the external system 300 via the external specific communication antenna 310.
Here, if the tracking system 100 is within the communication area of the external specific communication antenna 310, data communication of the GPS data and sensor data temporarily stored in the memory device 140 can be performed to the external system 300 via the external specific communication antenna 310 at a third predetermined time interval (e.g., 30 minutes).
These normal procedures 1 to 11 are the basic repeat procedures.

In addition, if data transmission/reception to the external system 300 fails in this normal procedure 11, a separate auxiliary routine process for retransmission will be launched in parallel, but since it is necessary to continue acquiring GPS data and sensor data during this time, the repeated process of this basic normal procedure 1 to normal procedure 11 will be maintained.
In addition, cases where the GPS data and sensor data are not received properly by the external system 300 may include, for example, when the tracking system 100 is not within the communication area of the external specific communication antenna 310, or when all or part of the data is missing due to bad weather or communication failure.

Normal procedures 1 to 11 shown in Figure 2 do not mention erasing the GPS data and sensor data that were temporarily stored in memory device 140, but since retransmission may be necessary until it can be confirmed that the data communication has been successfully received by external system 300 via external specific communication antenna 310, it is preferable to continue temporarily storing the data in memory device 140 until a predetermined time has elapsed, or until a notification of successful reception is received from external system 300.

[Auxiliary Routine Processing for Retransmission]
A typical LPWA does not assume that the success of data transmission and reception is confirmed by exchanging so-called ACK/NCK between the LPWA and the external system 300. In this embodiment, as an auxiliary routine process for retransmission in the tracking system 100 of the present invention, a case where an operation is assumed in which the success of data transmission and reception is confirmed between the external system 300 by exchanging so-called ACK/NCK (Case 1) is not performed, and a case where an operation is assumed in which an ACK/NCK is exchanged (Case 2) is performed will be described below.

[Auxiliary routine processing for retransmission: Operation without ACK/NCK exchange (Case 1)]
[Retransmission procedure for the first case]
The retransmission procedure for the first case will be explained.
In the first case, the error countermeasure is to have the external system 300 manage the GPS data and sensor data, identify the GPS data and sensor data that have not been received, and request a retransmission from the tracking system 100, and the tracking system 100 retransmits the relevant GPS data and sensor data in accordance with the retransmission request from the external system 300. For this purpose, a device is devised to perform sequence control by assigning a data ID number to reliably identify data that has failed to be transmitted or received.
That is, to perform sequence control, the GPS data is managed by assigning a GPS data serial number to each GPS data measured at a first predetermined time interval (for example, 15 minutes) by the GPS module 110 or the central control device 130. In normal procedure 3, the GPS data is written to the memory device 140 with the GPS data serial number assigned.

Furthermore, sequence management of the sensor data is performed by assigning a sensor data serial number to each piece of sensor data measured at a second predetermined time interval (for example, 10 minutes) by the sensor module 120 or the central control device 130. In the normal procedure 8 described above, the sensor data is written to the memory device 140 with the sensor data serial number assigned.
In the normal procedure 11 described above, when data communication is performed by the specific communication device 150, GPS data with a GPS data serial number and sensor data with a sensor data serial number are transmitted.

Here, after normal procedure 11, the specific communication device 150 does not know whether the data transmission/reception has failed or not. However, in this first case, even if normal procedure 11 is completed, there is a possibility that a retransmission request will be received from the external system 300 later. Therefore, the GPS data or sensor data for which data transmission/reception has been completed is not deleted from the memory device 140 but continues to be temporarily stored.

Sequence control is performed in the external system 300, and the external system 300 determines whether or not there is anything missing in the sequence order of the received data. If there is nothing missing, no particular retransmission request is made.
Here, it is assumed that the external system 300 has found that some of the GPS data and sensor data received up to that point are missing in sequence.
The external system 300 sends a request for retransmission of data that needs to be retransmitted, along with the GPS data serial number or the sensor data serial number, to the tracking system 100. The flow of this process is shown in FIG.

[Error Procedure 1-1: S21]
The communication control means 152 of the specific communication device 150 or the central control device 130 monitors whether a retransmission request for data specifying a GPS data serial number or a sensor data serial number has been received from the external system 300 (S21).

[Error Procedure 1-2: S22]
When a retransmission request is received, the communication control means 152 or central control unit 130 of the specific communication device 150 retransmits the GPS data or sensor data that has been assigned the GPS data serial number or sensor data serial number specified in the retransmission request, triggered by the passage of the next third predetermined time interval (S22).

[Error Procedure 1-3: S23]
In this first case, even after executing this error procedure 1-2, it is not clear whether data reception was successful or failed again in external system 300. Therefore, the GPS data and sensor data temporarily stored in memory device 140 are not erased, but continue to be temporarily stored as is. However, instead of waiting indefinitely, it is confirmed whether a predetermined retransmission reception time (for example, 12 hours or 24 hours) has passed (S23).
Similarly, if no retransmission request has been received (S21: N), the process proceeds to this error procedure 1-3 (S23) and checks whether a predetermined retransmission acceptance time (for example, 12 hours) has elapsed (S23).
If the predetermined retransmission acceptance time has not elapsed (S23: N), the process returns to the state of monitoring the reception of a retransmission request (return to S21).

[Error Procedure 1-4: S24]
In the above error procedure 1-3, if the temporary storage period reaches a certain period (for example, a predetermined period of 12 hours or 24 hours), it is assumed that a retransmission request will not be received from the external system 300, and the temporary storage in the memory device 140 is stopped and the corresponding data is erased. The length of the temporary storage period can be determined based on the capacity and operation of the memory device 140, etc.

[Auxiliary routine processing for retransmission: operation with ACK/NCK exchange (Case 2)]
[Retransmission procedure for the second case]
The retransmission procedure in the second case will be explained.
As described above, a typical LPWA does not assume that the LPWA and the external system 300 confirm the success of data transmission and reception by exchanging so-called ACK/NCK signals. However, in this embodiment, in the tracking system 100 of the present invention, it is also possible to assume an operation in which ACK/NCK signals are exchanged between the tracking system 100 and the external system 300 as an auxiliary routine process for retransmission (Case 2). The processing flow in this case is as shown in Figure 4 below.
In this second case, the error countermeasure is that the tracking system 100 and the external system 300 confirm the success/failure of transmission and reception each time, and so GPS data and sensor data that have not been received because no ACK is returned are resent from the tracking system 100. Therefore, it is not essential to assign a data ID number, but since it is often useful to have a data ID number, it is acceptable to assume here that a data ID number has been assigned.

[Retransmission procedure for the second case]
[Error Procedure 2-1]
After the normal procedure 11 described above, the specific communication device 150 or the central control device 130 monitors whether an ACK is returned from the external system 300 (S31).

[Error Procedure 2-2]
If an ACK is returned from the external system 300 (S31: Y), data transmission and reception including the GPS data and sensor data that have continued to be temporarily stored has been successfully executed, and the GPS data and sensor data that have been temporarily stored in the memory device 140 are erased (S32).
Thereafter, the process returns to the error procedure 2-1 to wait for monitoring ACK when transmitting and receiving the next data.

[Error Procedure 2-3]
If the specific communication device 150 is unable to communicate data using the specific communication module 151, that is, if no ACK is returned from the external system 300 (S31: N), the ACK return from the external system 300 may be delayed for some reason, so the unsent GPS data and sensor data written in the memory device 140 continue to be temporarily stored in the memory device 140 while monitoring the passage of a predetermined ACK waiting time (S33).
If the predetermined ACK waiting time has not yet elapsed (S33: N), the specific communication device 150 or the central control device 130 returns to the state of monitoring whether an ACK is returned from the external system 300 (to S31).
If the predetermined ACK waiting time has not yet elapsed (S33: Y), the process proceeds to error procedure 2-4: S34.

[Error Procedure 2-4: S34]
When the next third predetermined time interval (e.g., 30 minutes) has elapsed, the specific communication module 151 is caused to retransmit the GPS data and sensor data that have been temporarily stored in the memory device 140 and for which no ACK has been returned and that have been treated as unsent (S34). At the same time, the specific communication module 151 is also caused to perform data communication of the GPS data and sensor data that have been newly written into the memory device 140 up until the third predetermined time interval, according to the normal procedure 11 shown in FIG. 2 (S11).
Thereafter, the specific communication device 150 or the central control device 130 returns to the state of monitoring whether an ACK is returned from the external system 300 (to S31).

Furthermore, if an ACK is not returned for the retransmitted GPS data and sensor data despite the retransmission (S31: N), there is a possibility that the data transmission/reception has failed again, so the untransmitted GPS data and sensor data written in memory device 140 continues to be temporarily stored in memory device 140, while monitoring the passage of the next specified ACK waiting time (S33).If the specified ACK waiting time has passed without an ACK being returned (S33: Y), the data is retransmitted again (S34).
The error procedure 2-1 to error procedure 2-4 are repeated until an ACK is returned.

If an ACK is returned from the external system 300 (S31: Y), the corresponding GPS data and sensor data are deleted from the memory device 140 (S32).
In this second case, the central control device 130 or the specific communication device 150 will manage the data temporarily stored in the memory device 140, including both the data whose transmission and reception has been completed and the data whose transmission and reception has not yet been completed.

As described above, the tracking system 100 according to Example 1 has a simple device configuration including a GPS module, sensor module, central control device, memory device, GPS data temporary storage means, sensor data temporary storage means, and communication control means (LPWA communication module), and is capable of collecting GPS data and sensor data and transmitting them to the external system 300, and is also capable of retrying data transmission if the transmission or reception of the data fails. While continuing to temporarily store data that has not yet been transmitted, new data can be accumulated, and data transmission can be managed to ensure that no data is missed.

An application example of the tracking system of the present invention according to a second embodiment will be described.
The second embodiment is a construction machine attachment status detection system 400a.
FIG. 5(a) shows a simple construction machine attachment condition detection system 400a.
In this construction machine attachment status detection system 400a, the tracking target 200 shown in the first embodiment is a construction machine attachment 200a, and the tracking system 100 is attached to, wrapped around, or mounted inside a housing of the construction machine attachment 200a. It is preferable to ensure that the battery or cell has sufficient capacity.
The construction machine attachment 200a is a movable and replaceable part of the construction machine. For example, it refers to the bucket part, which is the workpiece attached to the end of the arm of the construction machine. The bucket part can be replaced with another attachment, allowing it to perform a variety of functions, such as scooping, lifting, grasping, cutting, crushing, and mowing. Buckets come in a variety of forms, including shovels, slope buckets, forestry attachments, mowing attachments, breakers, steel frame cutters, crushers, and forks. Since the construction machine attachment 200a has a single main body, it is temporarily stored when removed. Since it may be temporarily left near a work site, rather than in a management location such as a warehouse, there is a need to remotely monitor the location and status of the construction machine attachment 200a. Therefore, tracking is achieved by attaching the tracking system 100 of the present invention to the construction machine attachment 200a.
It is assumed that in many cases, the sensor module 120 will suffice as long as it is capable of measuring acceleration data and time data generated in the construction machine attachment 200a that is the tracking target.
The construction machine attachment status detection system 400a that receives data communication of GPS data and sensor data can detect the time that the construction machine attachment 200a is in use and the time that it is not in use.

An application example of the tracking system 100 according to the third embodiment of the present invention will be described.
The third embodiment is a state detection system 400b for agricultural machinery.
FIG. 5(b) shows a simple construction machine attachment status detection system 400a.
In this agricultural machinery status detection system 400b, the tracking target 200 shown in the first embodiment is the agricultural machinery 200b, and the tracking system 100 is attached to, wrapped around, or mounted inside a housing of the agricultural machinery 200b. It is preferable to ensure that the battery or cell has sufficient capacity.

There are various types of agricultural implements 200b, ranging in size from large to small, such as tractors, combine harvesters, rice transplanters, cultivators, transport vehicles, chemical sprayers, mowers, and chainsaws.
The agricultural implement 200b is generally stored in a barn or similar location on the farm, but it may also be temporarily left in a field or forest where agricultural work is being carried out, and there is a need to remotely monitor the location and status of the agricultural implement 200b. Therefore, the agricultural implement 200b can be tracked by attaching the tracking system 100 of the present invention to the agricultural implement 200b.
It is expected that in many cases, the sensor module 120 will be sufficient if it is capable of measuring acceleration data and time data generated in the agricultural implement 200b that is the tracking target.
The agricultural implement state detection system 400b that receives the data communication of the GPS data and sensor data can detect the time when the agricultural implement 200b is in use and the time when it is not in use.

An application example of the tracking system 100 according to the fourth embodiment of the present invention will be described.
The fourth embodiment is a victim search system 400c.
FIG. 6 shows the configuration of a simple victim search system 400c.
Regarding the external specific communication antenna, Figure 6(a) is an example of a configuration that uses a specific communication antenna 310 external to a fixed facility, and Figure 6(b) is an example of a configuration that uses an external specific communication antenna mounted on a mobile object such as a drone.
In this victim search system 400c, the tracking target 200 shown in the first embodiment is a human 200c who is a mountain climber or a marine passenger, and the tracking system 100 is stored in the clothing or life jacket of the mountain climber or marine passenger to be tracked. It is preferable to ensure that the battery or cell has sufficient capacity.
The person to be tracked may be, for example, a mountain climber or a person on an ocean vessel, but is not limited to these, and may also be a child who is prone to getting lost, an elderly person who is prone to going missing, or the like.
It is thought that people who are the target of tracking are not expected to be search targets in advance, but often become search targets after encountering some kind of trouble or unfortunate situation. There is a need to remotely search for the location and condition of the person 200c who is lost in such a situation. Therefore, mountain climbers, oceangoers, children who are prone to getting lost, and elderly people who are prone to going missing can be tracked by having the tracking system 100 stored in their clothing or life jackets just in case.

It is thought that GPS data alone will often be sufficient for searching for a missing person, but it is assumed that the sensor module 120 will also be able to detect the direction of movement if it is capable of measuring the acceleration data and time data generated in the missing person 200c who is the target of tracking.
The victim search system 400c, which receives data communication of GPS data and sensor data, can detect the location and direction of movement of the victim.

Next, it is conceivable that the location of the victim 200c is in an area where the external specific communication antenna 310 shown in Example 1 is not installed, such as in the mountains or at sea, and GPS data will not be obtained at the beginning of the search. Therefore, as shown in Figure 6(b), if the external specific communication antenna 310 is mounted on a mobile object, it will be possible to freely expand the search range. For example, if the external specific communication antenna 310 is mounted on a drone capable of flight, once the victim enters the communication area of the specific communication antenna mounted on the drone, information regarding the victim's location can be obtained through data communication from the tracking system 100 worn by the victim.

An application example of the tracking system 100 according to the fifth embodiment of the present invention will be described.
The fifth embodiment is an immobile state detection system 400d.
FIG. 7 shows the configuration of a simple stationary object state detection system 400d.
In this immobile state detection system 400d, the tracking target 200 shown in the first embodiment is a rock or mound 200d, which is normally an immobile object, and the tracking system 100 is attached to the tracking target, which is normally an immobile object, such as a rock, mound, forest, road, bridge, or tunnel. It is preferable to ensure that the battery or cell has sufficient capacity.

The immovable objects to be tracked are expected to remain stable and immobile under normal circumstances, but accidents such as movement or collapse can occur due to earthquakes, loosening of the ground, weather conditions such as heavy rain or heavy snow, etc. In such situations, there is a need to remotely monitor the position and status of the immovable objects 200d. Therefore, the immovable objects are tracked by attaching a tracking system 100 to them.
Furthermore, by focusing on acceleration data from the sensor data rather than GPS data, it is expected that slight changes in the movement of the vehicle and signs of such changes can be detected early on.
Therefore, it is preferable that the sensor module 120 is capable of measuring at least acceleration data occurring in the tracked object.
The external system 300 receives the sensor data and GPS data and detects the movement or signs of movement of the unattended object.

While the preferred embodiment of the present invention has been illustrated and described above, the present invention can be widely applied as a tracking system. Furthermore, by attaching the tracking system of the present invention to various tracked objects and monitoring their status, a status detection system for various tracked objects can be constructed.
It will be understood that various modifications can be made without departing from the spirit and scope of the invention.

REFERENCE SIGNS LIST 100 Tracking system 110 GPS module 120 Sensor module 130 Central control device 131 GPS data temporary storage means 132 Sensor data temporary storage means 140 Memory device 150 Specific communication device 151 Specific communication module 152 Communication control means 200 Tracking target
300 External system 310 External specific communication antenna 400a Construction machine attachment status detection system 400b Agricultural machine status detection system 400c Missing person search system 400d Immobile status detection system

Claims (11)

A tracking system that autonomously measures changes in at least one of a position, an attitude, and a moving speed of a tracked object and autonomously communicates the changes to an external system,
a GPS module for acquiring position data of the tracked object at a first predetermined time interval;
a sensor module that measures at least one of acceleration data, magnetic change data, illuminance change data, temperature change data, and time data of the tracked object at a second predetermined time interval;
A central control unit, a memory unit, and a specific communication unit,
the GPS module includes a GPS data temporary storage means for writing measurement results of the position data of the tracked object obtained at the first predetermined time interval into the memory device;
the sensor module comprises a sensor data temporary storage means for writing sensor data of the tracked object, which is any one of the acceleration data, the magnetic change data, the illuminance change data, the temperature change data, and the time data, obtained at the second predetermined time interval, into the memory device;
A tracking system characterized in that the specific communication device is equipped with a specific communication module based on the Low Power Wide Area communication standard and a communication control means for transmitting the GPS data and sensor data temporarily stored in the memory device to the external system via the external specific communication antenna at a third predetermined time interval when the specific communication device is within a communication area of the external specific communication antenna. The tracking system described in claim 1, characterized in that, when the specific communication device is unable to communicate data after a third predetermined time interval has elapsed, the communication control means continues to temporarily store the untransmitted GPS data and sensor data written in the memory device in the memory device, and, after the next third predetermined time interval has elapsed, causes the specific communication module to perform data communication of the untransmitted GPS data and sensor data and the GPS data and sensor data newly written until the next third predetermined time interval. a GPS data serial number is assigned to the GPS data at each of the first predetermined time intervals required for measurement by the GPS module or the central control device, and the GPS data is written into the memory device;
the sensor module or the central control device assigns a sensor data serial number to the sensor data at each of the second predetermined time intervals required for measurement, and writes the sensor data into the memory device;
The tracking system described in claim 2, characterized in that when the data communication is performed by the specific communication means, the GPS data with the GPS data serial number and the sensor data with the sensor data serial number are transmitted. The tracking system described in claim 3, characterized in that the communication control means or the central control device receives a retransmission request for data specifying the GPS data serial number or the sensor data serial number from the external system via the external specific communication antenna, and retransmits the GPS data with the GPS data serial number specified in the retransmission request and the sensor data with the specified sensor data serial number. A tracking system according to any one of claims 1 to 4, wherein the specific communication module is a Low Power Wide Area network device that enables low-power, long-distance wireless communication. the tracking object is a construction machine attachment that is a movable part and a replaceable part of the construction machine,
The sensor module is capable of measuring the acceleration data and the time data generated in the tracking target,
A construction machine attachment status detection system using a tracking system as described in claim 5, wherein an external system that receives the sensor data can detect the time the construction machine attachment is in use and the time it is not in use. The tracking target is an agricultural machine, and the sensor module is capable of measuring the acceleration data and the time data generated in the tracking target, respectively;
An agricultural machinery status detection system using the tracking system described in claim 5, wherein an external system that receives the sensor data can detect the position of the agricultural machinery, the time it is in use, and the time it is not in use. The tracking target is a human being such as a mountain climber, a marine passenger, a child, or a wanderer,
the person is wearing the tracking system of claim 5;
6. A missing person search system using a tracking system according to claim 5, wherein an external system that receives the GPS data can detect the position of the person being tracked. The missing person search system described in claim 8, wherein the external specific communication antenna is mounted on a flyable drone, and when the missing person is within the communication area of the specific communication antenna mounted on the drone, information regarding the location of the missing person can be obtained through data communication from the tracking system described in claim 5 worn by the missing person. The tracked object is a rock, an embankment, a forest, a road, a bridge, or a tunnel, which is normally an immovable object;
The tracking system according to claim 5 is attached to the immovable object,
The sensor module is capable of measuring at least the acceleration data generated in the tracking target,
An immovable object status detection system using the tracking system described in claim 5, wherein an external system that receives data communication of the GPS data and the sensor data can detect the movement or signs of movement of the immovable object. A tracking method for autonomously measuring changes in at least one of a position, an attitude, and a moving speed of a tracking target, and autonomously communicating the changes to an external system, comprising:
acquiring location data of the tracked object at a first predetermined time interval by a GPS module;
measuring, by a sensor module, at a second predetermined time interval, at least one change in acceleration data, magnetic change data, illuminance change data, temperature change data, or time data occurring in the tracking target;
Equipped with a central control unit, a memory unit, and a specific communication unit,
the GPS module executes a GPS data temporary storage for writing measurement results of the position data of the tracked object obtained at the first predetermined time interval into the memory device;
A tracking method characterized in that the sensor module performs temporary sensor data storage, writing any one of the sensor data of the tracked object, the acceleration data, the magnetic change data, the illuminance change data, the temperature change data, and the time data obtained at the second predetermined time interval, to the memory device, and if the specific communication device is within a communication area of an external specific communication antenna, performs specific communication to communicate the GPS data and the sensor data temporarily stored in the memory device to the external system via the external specific communication antenna at a third predetermined time interval according to a specific communication standard.