Wireless control system and wireless control method

Abstract

To improve the safety and efficiency of a radio control system.SOLUTION: A radio control system includes a control server, a wireless monitoring sensor, and a radio base station. The control server transmits a control signal to a radio mobile station via the radio base station. The wireless monitoring sensor monitors a state of a radio signal to which the control signal is transmitted, and notifies the control server when detecting a predetermined event in the state of the radio signal. When receiving the notification from the wireless monitoring sensor, the control server transmits the control signal for changing the state of the radio signal to the radio mobile station so as to cancel the detected event.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a wireless control system.

Background Art

[0002] There is a technique for detecting an event based on classification of channel state information in order to detect and monitor a wireless event, and there is Patent Document 1.

[0003] Patent Document 1 describes a configuration related to an apparatus for detecting an event. The apparatus described in Patent Document 1 includes a processor and a storage device that, when executed by the processor, confirms an instruction to train the processor to classify channel state information (CSI) and to detect an event based on the classification of CSI acquired during a monitoring stage. Training of the classifier includes acquiring, for each known event to be detected, training CSI of a wireless multipath channel between a wireless transmitter and a wireless receiver in a venue, the training CSI being derived from one or more probing signals transmitted from the transmitter to the receiver via the wireless multipath channel, during a period when the known event occurs in the venue, and training the classifier based on the known event and the training CSI associated with each event.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The device for detecting an event described in Patent Document 1 has a classifier for detecting an event based on the classification of channel state information (CSI) of radio waves emitted by a wireless communication system, but no consideration is given to mobile stations included in the wireless communication system or control methods when the mobile stations are under the control of a radio control system.

[0006] The present invention has been made in view of the above problems, and an object thereof is to provide a radio control system that can be controlled to return to a steady state when detecting an unsteady state in an area where the radio control system is operating.

Means for Solving the Problems

[0007] A typical example of the invention disclosed in the present application is as follows. That is, a radio control system comprising a control server, a radio monitoring sensor, and a radio base station, wherein the control server transmits a control signal to a radio mobile station via the radio base station, and the radio monitoring sensor monitors the state of a radio signal to which the control signal is transmitted, and when detecting a predetermined event, notifies the control server, and the control server is characterized by transmitting a control signal to the radio mobile station. An abnormality caused by interference between the wireless mobile station and the monitoring target is indicated in a delay profile showing the state of delay When detecting a predetermined event, it notifies the control server, and the control server Estimate the position and state of the monitoring target from the notification received from the wireless monitoring sensor, calculate the positional relationship between the wireless mobile station and the monitoring target, and if there is a possibility of interference between the wireless mobile station and the monitoring target, change the movement plan of the wireless mobile station to avoid interference between the wireless mobile station and the monitoring target, and according to the changed movement plan is characterized by transmitting a control signal to the radio mobile station.

Effects of the Invention

[0008] According to one aspect of the present invention, the safety and efficiency of the radio control system can be improved. Problems, configurations, and effects other than those described above will be clarified by the description of the following embodiments.

Brief Description of the Drawings

[0009]

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Figure 12A

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Figure 15B

Modes for Carrying Out the Invention

[0010] In the following embodiments, when necessary for convenience, the description will be divided into a plurality of sections or embodiments. In the following embodiments, when referring to the number of elements, etc. (including the number, numerical value, quantity, range, etc.), unless otherwise specifically stated or clearly limited to a specific number in principle, it is not limited to that specific number, and it may be more than or less than the specific number. In the following embodiments, the constituent elements (including processing steps, etc.) are not necessarily essential, unless otherwise specifically stated or clearly considered essential in principle.

[0011] Also, each configuration, function, processing unit, processing means, etc. in the following embodiments may be realized by realizing a part or all of them as, for example, an integrated circuit or other hardware. Also, each configuration, function, processing unit, processing means, etc. described later may be realized as a program executed on a computer. That is, it may be realized as software. Information such as programs, tables, files, etc. for realizing each configuration, function, processing unit, processing means, etc. can be stored in a storage device such as a memory, hard disk, SSD (Solid State Drive), or in a storage medium such as an IC card, SD card, DVD.

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings for explaining the embodiments, members having the same function are denoted by the same or related reference numerals, and the repeated description thereof will be omitted. Also, in the following embodiments, the description of the same or similar parts will not be repeated in principle unless particularly necessary.

[0013] <First Embodiment> [System Configuration] The wireless control system 200 of the first embodiment is composed of a control server 201, a wireless monitoring sensor 103, and a wireless base station 101. The wireless base station 101 communicates wirelessly with the wireless mobile station 102. Hereinafter, the wireless control system 200 according to the first embodiment of the present invention will be described with reference to the drawings.

[0014] FIG. 1 is a diagram showing a wireless communication environment according to the first embodiment. The wireless communication environment 100 may be either an indoor environment such as a factory or an outdoor environment such as a construction site. The wireless communication environment 100 includes a wireless base station 101, a wireless mobile station 102, a wireless monitoring sensor 103, and a monitoring target 104. The monitoring target 104 is a physical object that does not have a communication function and exists within the communication range of the wireless communication system. For example, it may be a movable object such as a forklift or a person. Further, the monitoring target 104 may or may not have a wireless communication function. For example, it may be a wireless mobile station 102 or an object not under the management of the wireless control system 200. The wireless base station 101 sends control commands such as movement instructions to the wireless mobile station 102 by transmitting and receiving radio waves 105 to and from the wireless mobile station 102. The radio wave 105 propagates not only as a direct wave to the wireless mobile station 102 but also as multipath waves 106, 107, 108 and reaches the wireless monitoring sensor 103. At this time, the multipath wave 106 is affected by the monitoring target 104 and reaches the wireless monitoring sensor 103 after repeating reflections. Depending on the position of the monitoring target 104, the states (e.g., delay time, intensity) of the multipath waves 106, 107, 108 change. The wireless monitoring sensor 103 receives these multipath waves and analyzes the channel state information. The channel state information analyzed by the wireless monitoring sensor 103 is, for example, a delay profile represented by the received signal strength and the propagation delay time. Although an example is described in which the radio wave 105 transmitted by the wireless base station 101 and the radio waves 106, 107, 108 received by the wireless monitoring sensor 103 are the same radio wave, these two may be different (e.g., different frequencies) radio waves.

[0015] Next, with reference to FIG. 2, the configuration of the wireless control system 200 will be described. The wireless control system 200 is composed of a control server 201, a wireless monitoring sensor 103, and a wireless base station 101. The control server 201, the wireless monitoring sensor 103, and the wireless base station 101 are connected by a network (for example, Ethernet). The wireless base station 101 communicates with the wireless mobile station 102 via wireless. The processing executed by the wireless control system 200 will be described later with reference to other figures.

[0016] Next, with reference to FIG. 3, the configuration of the wireless monitoring sensor 103 will be described. The wireless monitoring sensor 103 includes a wireless reception unit 301, a channel state information analysis unit 302, a pattern learning unit 303, a pattern detection unit 304, and a notification unit 305. The processes executed by the wireless monitoring sensor 103 will be described later with reference to other figures. The wireless reception unit 301 converts the radio wave captured by an antenna (not shown) into a baseband signal. The channel state information analysis unit 302 creates a delay profile with the frequency and delay time on the horizontal axis and the received radio wave intensity on the vertical axis by performing delay spread analysis on the radio wave received by the wireless reception unit 301. For example, as shown in FIGS. 15A and 15B, the delay profiles are different when the person who is the monitoring target 104 is walking and when the person has fallen. A delay profile mapped in a two-dimensional space with the delay time and the received radio wave intensity as axes is created. The pattern learning unit 303 learns the relationship between the created delay profile and the state of the monitoring target 104 in the wireless communication environment, and creates an inference model capable of estimating the state of the monitoring target 104 from the delay profile. The state of the monitoring target 104 input to the pattern learning unit 303 may be a camera image that captures the inside of the wireless communication environment 100, the state of the monitoring target 104 input by the administrator, or the position information of the monitoring target 104 obtained from another system (for example, in the second embodiment, the position information of the movable shelf 801 obtained from the warehouse management system). The pattern detection unit 304 estimates the state of the monitoring target 104 from the delay profile that is the analysis result of the channel state information analysis unit 302 using the inference model created by the pattern learning unit 303. The inference model may be a machine learning model or a multi-dimensional numerical model derived by regression analysis. The notification unit 305 detects a predetermined event from the state of the monitoring target 104 estimated by the pattern detection unit 304 and notifies the control server 201.

[0017] Note that some functions of the wireless monitoring sensor 103 may be executed by the control server 201. For example, the functions of the channel state information analysis unit 302, the pattern learning unit 303, and the pattern detection unit 304 may be executed by the control server 201. Also, using edge computing technology, some functions of the wireless monitoring sensor 103 may be executed by an edge computer (not shown) distributed near the wireless monitoring sensor 103. For example, the functions of the pattern learning unit 303 and the pattern detection unit 304 may be executed by the edge computer.

[0018] Next, with reference to FIG. 4, the processing executed by the control server 201 shown in FIG. 2 will be described. In the steady state, the control server 201 transmits a control signal in the steady state to the mobile station (401). Next, the control server 201 receives state information from the wireless mobile station 102 (402). Then, the control server 201 waits for a notification from the wireless monitoring sensor 103 (403). If the control server 201 does not receive a notification from the wireless monitoring sensor 103, it returns to step 401 and repeats the communication of the control signal in the steady state. When the control server 201 receives a notification from the wireless monitoring sensor 103, it estimates the position and state of the monitoring target 104 from the information regarding the channel state included in the received notification (404). Next, the control server 201 calculates the position information of the monitoring target 104 such that the channel state information included in this notification changes (405). Then, the control server 201 transmits an emergency control signal including the calculated position information to the mobile station (406). Then, the control server 201 determines whether the notification from the wireless monitoring sensor 103 has stopped (407). While the notification from the wireless monitoring sensor 103 continues, it calculates the position information of the monitoring target 104 (405) and continues to transmit the emergency control signal (406). On the other hand, when the notification has stopped (Yes in 407), the control server 201 returns to step S401 and repeats the communication of the control signal in the steady state.

[0019] The emergency control signal includes, for example, a movement control signal for the wireless mobile station 102 to leave the intrusion prohibited area, and a movement control signal for the wireless mobile station 102 to approach the monitoring target 104 where an abnormality has occurred in order to investigate the abnormal state.

[0020] Next, with reference to FIG. 5, the processing executed by the wireless monitoring sensor 103 shown in FIG. 2 will be described. The wireless monitoring sensor 103 waits for reception of a radio wave. When a radio wave is received (501), the channel state information of the received radio wave is analyzed (502). Then, the state of the monitoring target 104 is estimated from the channel state information using the learned inference model (503). The result of the estimation is written into the monitoring target state information 602, the monitoring target position information 603, and the emergency state flag 604 in the channel state information table 600 (see FIG. 6). The emergency state flag 604 is recorded as 1 when an event predetermined as a state to be notified to the control server 201 has occurred. If the emergency state flag 604 is 1, since an event to be notified to the control server 201 has occurred (Yes in 504), the control server 201 is notified of the state abnormality (505). On the other hand, if the emergency state flag 604 is 1, since no event to be notified to the control server 201 has occurred, the process returns to step 501 and waits for reception of a radio wave. Note that, without determining the occurrence of an event based on the emergency state flag 604 in step 504, all of the estimated states of the monitoring target 104 may be transmitted to the control server 201.

[0021] FIG. 6 is a diagram showing a channel state information table 600 in which the result of estimating the state of the monitoring target 104 from channel state information (delay profile) is written. The channel state information table 600 includes a delay profile ID 601, monitoring target state information 602, monitoring target position information 603, and an emergency state flag 604, and these pieces of information are recorded in association with each other. During learning, the inference model uses the delay profile ID 601, the monitoring target state information 602, the monitoring target position information 603, and the emergency state flag 604 as teacher data for learning. Also, during inference, the inference model takes the delay profile as input and outputs the monitoring target state information 602, the monitoring target position information 603, and the emergency state flag 604 as inference results. The wireless monitoring sensor 103 records a plurality of pieces of channel state information (delay profiles) in association with the delay profile ID 601. The physical state of the monitoring target 104 in the channel state is recorded in the monitoring target state information 602, and the information on the position where the monitoring target 104 exists in the channel state is recorded in the monitoring target position information 603. Then, an emergency state flag 604 for determining whether the recorded state information is in a normal state or an abnormal state for the wireless control system 200 is recorded. The emergency state flag 604 as teacher data may be set manually by the user of the wireless control system 200 or automatically set by the wireless control system 200. For example, a state with a generation probability lower than a certain level may be determined as an emergency state, or in association with the operating state of the wireless control system 200, the channel state information when the system is stopped may be determined as an emergency state, and the wireless control system 200 may automatically set the emergency state flag 604.

[0022] Next, with reference to FIG. 7, the processing executed by the wireless mobile station 102 shown in FIG. 2 will be described. The wireless mobile station 102 waits for a movement instruction from the control server 201 (701), and determines whether it has received a movement instruction from the control server 201 (702). If the wireless mobile station 102 receives a movement instruction from the control server 201 (Yes in 702), it moves according to the movement instruction (703). Then, if the wireless mobile station 102 continuously receives a movement instruction, it continues to move according to the movement instruction. Also, if the movement instruction stops, the wireless mobile station 102 waits for a movement instruction in step 701.

[0023] With the configuration and processing described above, the wireless control system 200 of the first embodiment can receive a notification from the wireless monitoring system and send a movement instruction to the wireless mobile station 102, thereby optimizing the positional relationship between the monitoring target 104 and the wireless mobile station 102. As a result, the safety and efficiency of the wireless control system 200 can be improved.

[0024] <Second Embodiment> The second embodiment relates to the processing for realizing a specific function in the configuration shown in the first embodiment. Hereinafter, the second embodiment will be described with reference to FIGS. 8A to 12B.

[0025] FIGS. 8A and 8B are diagrams showing a wireless communication environment according to the second embodiment, and show the environment in a logistics warehouse 800 where an automatic guided vehicle (AGV) operates. FIG. 8A is a top view of the logistics warehouse 800, and FIG. 8B is a side view of the logistics warehouse 800. Also, an AGV control system 900 that operates the AGV in the logistics warehouse is operating, and the AGV control system communicates with the AGV wirelessly.

[0026] As shown in FIG. 8A, inside the logistics warehouse 800, there are arranged a movable shelf 801, a shelf installation area 802, an AGV 803, a wireless base station 101, a wireless monitoring sensor 103, and a picking area 806. The movable shelf 801 contains the goods to be delivered and is placed in a predetermined shelf installation area 802. The AGV 803 moves a predetermined movable shelf 801 to the picking area 806 according to the delivery instruction. When a worker working in the picking area 806 takes out the goods from the movable shelf 801, the movable shelf 801 after picking is returned to a predetermined position within the shelf installation area 802 by the AGV 803. The above is a series of operations related to picking. The AGV 803 has a wireless communication terminal and transmits and receives movement instruction information with the AGV control system 900 via the wireless base station 101 by wireless communication. The wireless monitoring sensor 103 receives radio waves inside the logistics warehouse, analyzes the channel state information, and classifies the analysis results.

[0027] In the logistics warehouse 800 shown in FIG. 8A, the wireless base station 101 is installed on the ceiling to expand the reach of the radio wave, and the wireless monitoring sensor 103 is installed on the ceiling to expand the reception range of the radio wave. However, the wireless base station 101 and the wireless monitoring sensor 103 may be installed above the height of the movable shelf 801. Also, the wireless base station 101 and the wireless monitoring sensor 103 may be installed below for each passage where the AGV 803 travels.

[0028] As shown in FIG. 8B, when the logistics warehouse 800 is viewed from the side, the movable shelf 801 is lifted and moved by the AGV 803. The wireless base station 101 and the wireless monitoring sensor 103 are preferably installed on the ceiling because there are few obstacles to radio wave propagation.

[0029] Next, with reference to FIG. 9, the configuration of the AGV control system 900 will be described. The AGV control system 900 includes a control server 901, a wireless monitoring sensor 103, a wireless base station 101, and a host server 905. The control server 901, the wireless monitoring sensor 103, the wireless base station 101, and the host server 905 are connected via a network. The wireless base station 101 communicates with the AGV 904 wirelessly. The control server 901 mainly executes processing related to channel state information, and the host server 905 mainly executes processing for the operation management plan and movement control of the AGV. Details of the processing content of the AGV control system 900 will be described with reference to the following figures.

[0030] Comparing with FIG. 1, in the second embodiment, the wireless mobile station 102 is mounted on the AGV 803, and the mobile rack 801 is the monitoring target 104.

[0031] Next, with reference to FIG. 10, the processing executed by the control server 901 shown in FIG. 9 will be described. The control server 901 waits for a notification from the wireless monitoring sensor 103 (1001), and determines whether a notification from the wireless monitoring sensor 103 has been received (1002). When the control server 901 receives a notification from the wireless monitoring sensor 103 (Yes in 1002), it estimates the position and state of the monitoring target 104 based on the channel state information included in the received notification (1003). Next, the control server 901 calculates the position information of the monitoring target 104 such that the channel state information received in this notification changes (1004). Then, the control server 901 transmits an emergency notification including the calculated position information to the host server 905 (1005).

[0032] Next, with reference to FIG. 11, the processing executed by the upper server 905 shown in FIG. 9 will be described. In the steady state, the upper server 905 transmits a steady-state control signal to the AGV (1101). Next, the upper server 905 receives position information from the AGV 904 (1102). Then, the upper server 905 waits for a notification from the control server 901 (1103). If the upper server 905 does not receive a notification from the control server 901, it returns to step 1101 and repeats the communication of the steady-state control signal. When the upper server 905 receives a notification from the control server 901, it collates the control plan of the AGV 904 with the content of the emergency notification and changes the control plan (1104). Next, the upper server 905 transmits a control signal of the control plan changed based on this emergency notification to the AGV 904 (1105). Then, the upper server 905 determines whether the notification from the control server 901 has stopped (1106). While the notification from the wireless monitoring sensor 103 continues, it changes the control plan (1104) and continues to transmit the emergency control signal (1105). On the other hand, when the notification has stopped (Yes in 1106), the upper server 905 returns to step S1101 and repeats the communication of the steady-state control signal.

[0033] Referring to FIGS. 12A and 12B, an example of how the operating environment of the AGV changes due to the processes described in FIGS. 10 and 11, that is, the state transition from state A (1200) to state B (1210) will be described. FIG. 12A shows state A (1200) in which a plurality of mobile shelves 801 are gathered in the vicinity of the picking area 806. In state A (1200), when the AGV 803 returns the mobile shelf 801 that has completed the picking operation in the picking area 806 to the empty shelf installation area 802, there is only space at a position far from the picking area 806 (for example, shelf installation area 802D), and it is necessary to move the mobile shelf 801 along the path indicated by the arrow, for example. This will cause problems such as an increase in the travel route of the AGV 803, an extension of the working time, and an increase in the power energy consumption of the AGV. Therefore, the AGV system determines that this state is an emergency state that requires countermeasures. The wireless monitoring sensor 103 recognizes that the environment of the logistics warehouse 800 has reached state A by analyzing the channel state information, and sets the emergency state flag 604 in the channel state information table 600. In addition, upon receiving the emergency notification, the control server 901 sets an operation plan for changing the state of the AGV system to the upper server 905.

[0034] FIG. 12B shows state B (1210) which is an example of the result of executing the reconfigured operation plan. In state B (1210), the mobile shelves 801 are not concentrated in the vicinity of the picking area 806, but are distributed throughout the shelf installation area 802. In state B (1210), the AGV 8013 can return the mobile shelf 801 whose picking operation has been completed in the picking area 806 to the empty shelf installation area 802C in the vicinity of the picking area 806. Therefore, in state B (1210), compared with state A (1200), the travel distance of the AGV 803 is shortened, so the operation time can be shortened and the consumption of the power energy of the AGV 803 can be suppressed. The wireless monitoring sensor 103 learns in advance a state in which the logistics warehouse environment becomes state B (1210) by analyzing the channel state information, and outputs an emergency notification to the control server 901 based on the learned classification result. The control server 901 transmits an emergency notification including the calculated position information to the upper server 905. The upper server 905 creates an operation plan for the AGV so that the environment in the logistics warehouse becomes state B.

[0035] With the configuration and processing described above, the AGV control system 900 of the second embodiment can transmit a movement instruction to the AGV 803 based on the monitoring result of the wireless monitoring sensor 103, and can optimize the position of the monitoring target 104 (mobile shelf 801). As a result, the safety and efficiency of the AGV control system 900 can be improved.

[0036] <Third Embodiment> The third embodiment relates to a process for realizing another specific function in the configuration shown in the first embodiment. Hereinafter, the third embodiment will be described with reference to FIGS. 13 to 14.

[0037] FIG. 13 is a diagram showing a wireless communication environment according to the third embodiment. In a mine, it shows an environment where an unmanned transport truck 1301 called an AHS (Autonomous Haulage System) operates. Also, in the mine, a wireless control system 200 for operating the AHS truck 1301 is operating. A transport path 1300 is provided in the mine, and the AHS truck 1301 travels on the transport path 1300. The AHS truck 1301 communicates wirelessly with a wireless base station 101. Also, a wireless monitoring sensor 103 receives radio waves around the transport path 1300 in the mine, analyzes and classifies channel state information. An obstacle 1304 generated by a rockfall, a collapse, or the like becomes a monitoring target 104. The radio wave environment is different between the case where an obstacle 1304 exists on the transport path 1300 and the case where no obstacle 1304 exists on the transport path 1300, and the wireless monitoring sensor 103 monitors this change in the radio wave environment. The AHS control system that controls the travel of the AHS truck 1301 may be composed of a control server 201, a wireless monitoring sensor 103, and a wireless base station 101, similar to the wireless control system 200 shown in FIG. 2. The wireless mobile station 102 is mounted on the AHS truck 1301, and the obstacle 1304 is the monitoring target 104.

[0038] Next, with reference to FIG. 14, the processing executed by the control server 201 according to the third embodiment will be described. In FIG. 14, in the steady state, the control server 201 transmits a control signal in the steady state to the mobile station (1401). Next, the control server 201 receives state information from the wireless mobile station 102 (1402). Then, the control server 201 waits for a notification from the wireless monitoring sensor 103 (1403). If the notification from the wireless monitoring sensor 103 is not received, the control server 201 returns to step 1401 and repeats the communication of the control signal in the steady state. When the notification from the wireless monitoring sensor 103 is received, the position and state of the monitoring target 104 (for example, the obstacle 1304 on the transport path 1300) are estimated from the information regarding the channel state included in the received notification (1404). Next, the control server 201 calculates the positional relationship between the wireless mobile station 102 and the monitoring target 104 (1405). Then, the control server 201 determines whether it is necessary to change the movement plan of the AHS truck 1301 (wireless mobile station 102) (1406). For example, when the AHS truck 1301 travels according to the current movement plan and overlaps with the position of the obstacle 1304, it may be determined that it is necessary to change the movement plan of the AHS truck 1301 because the AHS truck 1301 and the obstacle 1304 interfere with each other and the work performed at the wireless mobile station 102 is hindered. If there is no need to change the movement plan of the wireless mobile station 102, the process returns to step 1401 and repeats the communication of the control signal in the steady state. On the other hand, if it is necessary to change the movement plan of the wireless mobile station 102, an emergency control signal is transmitted to the wireless mobile station 102 (1407). The emergency control signal transmitted in step 1407 is, for example, to cause the AHS truck 1301 (wireless mobile station 102) to stop urgently. Then, the control server 201 determines whether the notification from the wireless monitoring sensor 103 has stopped (1408), and continues to transmit the emergency control signal (1407) while the notification from the wireless monitoring sensor 103 continues. On the other hand, when the obstacle 1304 is removed and the notification from the wireless monitoring sensor 103 has stopped (Yes in 1408), the control server 201 returns to step S1401 and repeats the communication of the control signal in the steady state.

[0039] For example, in the situation shown in FIG. 13, the wireless monitoring sensor 103 detects that the obstacle 1304, which is the monitoring target 104, has blocked the conveyance path 1300, and by sending a stop command to the AHS truck 1301 equipped with the wireless mobile station 102, the safety of the AHS truck 1301 controlled by the AHS control system can be improved.

[0040] With the configuration and processing described above, the AHS control system in the third embodiment receives a notification from the wireless monitoring sensor 103 and sends a control signal to the wireless mobile station 102, and can optimize the positional relationship between the monitoring target 104 and the wireless mobile station 102. As a result, the safety and efficiency of the AHS truck 1301 controlled by the AHS control system can be improved.

[0041] As described above, the wireless control system 200 of the embodiment of the present invention includes a control server 201, a wireless monitoring sensor 103, and a wireless base station 101. The control server 201 sends a control signal to the wireless mobile station 102 via the wireless base station 101. The wireless monitoring sensor 103 monitors the state of the wireless signal to which the control signal is transmitted, and when detecting a predetermined event in the state of the wireless signal, notifies the control server 201. When receiving a notification from the wireless monitoring sensor 103, the control server 201 sends a control signal whose state of the wireless signal changes so that the detected event is eliminated to the wireless mobile station 102. Therefore, by detecting the non-steady state of the operating area of the wireless control system 200 and controlling it to return to the steady state, the safety and efficiency of the wireless control system 200 can be improved.

[0042] In addition, since the state of the wireless signal is the delay of the wireless signal received by the wireless monitoring sensor 103, it is less affected by noise and can accurately capture the change of the monitoring target 104. Also, the number of sensors can be reduced compared to using a camera.

[0043] Furthermore, it includes a higher-level server 905 that generates a control signal to be transmitted to the wireless mobile station 102. When the control server 901 receives a notification from the wireless monitoring sensor 103, the higher-level server 905 generates a control signal for changing the state of the wireless signal so that the detected event is resolved, and transmits the generated control signal to the wireless mobile station 102. Therefore, the mobile shelves 801 can be distributedly arranged in the logistics warehouse 800, the travel distance of the AGV 803 can be shortened, and the efficiency of item sorting can be improved.

[0044] In addition, the control server 201 estimates the position and state of the monitoring target 104 from the notification received from the wireless monitoring sensor 103, calculates the positional relationship between the wireless mobile station 102 and the monitoring target 104, and if there is a possibility that the wireless mobile station 102 and the monitoring target 104 interfere with each other, changes the movement plan of the wireless mobile station 102 for the wireless mobile station 102 and the monitoring target 104 to avoid interference, and transmits a control signal according to the changed movement plan to the wireless mobile station 102. Therefore, the safety and efficiency of the wireless control system 200 can be improved.

[0045] Note that the present invention is not limited to the above-described embodiments, and includes various modifications and equivalent configurations within the scope of the appended claims. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to those having all the configurations described. Also, a part of the configuration of one embodiment may be replaced with the configuration of another embodiment. Also, the configuration of another embodiment may be added to the configuration of one embodiment. Also, for a part of the configuration of each embodiment, addition, deletion, or replacement with other configurations may be made.

[0046] Furthermore, some or all of the above-described configurations, functions, processing units, processing means, etc. may be realized in hardware, for example, by designing them with an integrated circuit or the like, or may be realized in software by a processor interpreting and executing a program for realizing each function.

[0047] Information such as programs, tables, and files that implement each function can be stored in a storage device such as a memory, hard disk, SSD (Solid State Drive), or a recording medium such as an IC card, SD card, or DVD.

[0048] In addition, the control lines and information lines show those considered necessary for explanation, and do not necessarily show all the control lines and information lines required for implementation. In practice, it is reasonable to consider that almost all components are interconnected.

Explanation of Signs

[0049] 100 Wireless communication environment 101 Wireless base station 102 Wireless mobile station 103 Wireless monitoring sensor 104 Object to be monitored 105 Radio wave (direct wave) 106 - 108 Radio waves (multipath waves)

Claims

1. A wireless control system comprising: a control server, a wireless monitoring sensor, and a wireless base station, wherein the control server transmits a control signal to a wireless mobile station via the wireless base station, the wireless monitoring sensor monitors the state of the wireless signal to which the control signal is transmitted, and when detecting a predetermined event indicating an abnormality due to interference between the wireless mobile station and the monitoring target in a delay profile indicating the state of delay of the wireless signal, notifies the control server, the control server estimates the position and state of the monitoring target from the notification received from the wireless monitoring sensor, calculates the positional relationship between the wireless mobile station and the monitoring target, when there is a possibility that the wireless mobile station and the monitoring target interfere with each other, changes the movement plan of the wireless mobile station to avoid the interference between the wireless mobile station and the monitoring target, and transmits a control signal according to the changed movement plan to the wireless mobile station. A wireless control system characterized by the above.

2. The wireless control system according to claim 1, wherein the wireless monitoring sensor comprises a wireless receiving unit for receiving a wireless signal, a channel state information analysis unit for calculating channel state information from the state of the received wireless signal, a pattern learning unit for learning the monitoring target and the channel state information to generate an inference model, a pattern detection unit for detecting a predetermined event using the generated inference model, and a notification unit for notifying the detected event to the control server. A wireless control system characterized by the above.

3. The wireless control system according to claim 2, wherein the wireless monitoring sensor records channel state information including identification information of the channel state information, monitoring target state information indicating the state of the monitoring target, monitoring target position information indicating the position of the monitoring target, and an emergency state flag indicating whether the channel state information is emergency. A wireless control system characterized by the above.

4. The wireless control system according to claim 1, further comprising a higher-level server for generating a control signal to be transmitted to the wireless mobile station, wherein when the control server receives a notification from the wireless monitoring sensor, the higher-level server generates the control signal on behalf of the control server and transmits the generated control signal to the wireless mobile station. A wireless control system characterized by the above.

5. The wireless control system according to claim 4, wherein the higher-level server changes the movement plan of the wireless mobile station based on the position information received from the control server. A wireless control system, characterized by transmitting a control signal according to a changed movement plan to the wireless mobile station. **Claim 6**: A wireless control method executed by a wireless control system, wherein the wireless control system includes a control server, a wireless monitoring sensor, and a wireless base station, and the wireless control method includes: the control server transmitting a control signal to the wireless mobile station via the wireless base station; when the wireless monitoring sensor detects a predetermined event indicating an abnormality due to interference between the wireless mobile station and the monitoring target in a delay profile indicating the state of delay of the wireless signal to which the control signal is transmitted, the wireless monitoring sensor notifies the control server; the control server estimates the position and state of the monitoring target from the notification received from the wireless monitoring sensor; calculates the positional relationship between the wireless mobile station and the monitoring target; when there is a possibility that the wireless mobile station and the monitoring target may interfere, changes the movement plan of the wireless mobile station to avoid interference between the wireless mobile station and the monitoring target; and transmits a control signal according to the changed movement plan to the wireless mobile station.

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