JP4822194B1 - Moving direction specifying system and moving direction specifying program - Google Patents

Abstract

To provide a moving direction specifying system and a moving direction specifying program capable of specifying a moving direction of a moving body using a wireless tag without separately providing a sensor for specifying the moving direction of the moving body. To do.
A moving direction specifying system 1 is a moving direction specifying system 1 that specifies a moving direction of a moving body, and includes a wireless tag 2 attached to the moving body and a plurality of positions along the moving direction of the moving body. And the detection unit 4 that detects the wireless tag 2 by communicating with the wireless tag 2 and the transition of the detection state of the wireless tag 2 in each of the detection units 4 that are arranged at a plurality of positions. A moving direction specifying unit 6a for specifying a moving direction.
[Selection] Figure 2

Description

  The present invention relates to a moving direction specifying system and a moving direction specifying program.

  2. Description of the Related Art In recent years, inventory management and distribution management of goods, management of human entrance / exit, and the like have been performed using wireless tags such as RFID (Radio Frequency IDentification) tags and Wi-Fi (Wireless Fidelity) tags. In such management, for example, in addition to the use of information stored in the wireless tag, whether the article to be managed was entered or exited, or whether a person entered or exited the room It is important to specify the moving direction of an article or a human body with a wireless tag attached.

  For this reason, for example, by identifying a passer-by who enters and exits a security zone where outsiders are restricted from entering, and specifying the direction of movement of the passer-by, the outsider's unauthorized entry room is monitored and an alarm is issued. An outsider monitoring system has been proposed. In this system, two position detection sensors, such as an infrared sensor, are installed along the passage direction at a gate installed at the entrance to the security zone. Further, an acoustic magnetic sensor for detecting a magnet tag carried by a passerby is installed at the gate. Based on the detection order of each position detection sensor, the movement direction of the passer-by is determined, and the passer-by is specified according to whether or not the magnet tag is detected by the acoustic magnetic sensor (for example, Patent Document 1). reference).

JP 2003-303382 A

  However, in the conventional system as described above, it is necessary to separately provide a sensor for specifying the passerby and a sensor for detecting the direction of movement of the passerby, which causes a complicated configuration of the entire system. It was. Therefore, there is room for reducing the cost for system configuration.

  The present invention has been made in view of the above, and it is possible to specify the moving direction of the moving object using a wireless tag without separately providing a sensor for specifying the moving direction of the moving object. It is an object of the present invention to provide a moving direction specifying system and a moving direction specifying program.

In order to solve the above-described problems and achieve the object, the moving direction specifying system according to claim 1 is a moving direction specifying system for specifying a moving direction of a moving body, and is a wireless attached to the moving body. A tag, a detection unit disposed at a plurality of positions along a moving direction of the moving body, and detecting the wireless tag by communicating with the wireless tag; and each of the detection units disposed at the plurality of positions Based on the transition of the detection state of the wireless tag, the moving direction specifying means for specifying the moving direction of the moving body, and the speed measuring means for measuring the moving speed of the moving body, the moving direction specifying means, After the detection of the wireless tag, if the wireless tag has not been detected by all of the detection means and a certain period of time has elapsed, the mobile body with the wireless tag attached is moved in the moving direction. The detection unit transmits a read request signal, the wireless tag transmits a response signal when the read request signal is received, and the detection unit transmits the read request signal a predetermined number of times. When the number of times that the response signal is received from the wireless tag when transmitted is equal to or greater than the required number of responses according to the speed of the moving body measured by the speed measuring means, the wireless tag is detected. To do.

A moving direction specifying program according to claim 2 is a moving direction specifying program for causing a computer to specify a moving direction of a moving body, and is arranged at a plurality of positions along the moving direction of the moving body. And a detection step of detecting the wireless tag by communicating with the wireless tag attached to the mobile body, and a transition of a detection state of the wireless tag in each of the detection means arranged at the plurality of positions. , Causing the computer to execute a moving direction specifying step for specifying the moving direction of the moving body, and a speed measuring step for measuring the moving speed of the moving body by speed measuring means, and in the moving direction specifying step, the detection After the wireless tag is detected by the means, if the wireless tag is not detected by all the detection means and a certain time has passed, The mobile unit with the wireless tag is excluded from a specific target of the movement direction, and when the reading request signal is transmitted a predetermined number of times from the detection unit in the detection step, the detection unit It is assumed that the wireless tag is detected when the number of times the response signal for the reading request signal is received is equal to or greater than the required number of responses corresponding to the speed of the moving body measured by the speed measuring means.

According to the moving direction specifying system according to claim 1 and the moving direction specifying program according to claim 2, the number of times the response signal is received from the wireless tag when the read request signal is transmitted a predetermined number of times is the speed measuring means. If the wireless tag is detected when the number of response times corresponding to the speed of the moving body measured in step S is exceeded, the wireless tag is located within the detectable range of the detection means, and the detection means is surely Only when a response signal can be received from the wireless tag, the wireless tag can be detected. For example, the probability of erroneous detection of the wireless tag due to reflection of the wireless signal can be reduced.

Also, after the wireless tag is detected by the detection means, if the the wireless tag in all detection means has passed a predetermined time or more is not detected, a specific moving direction of the moving body to which the wireless tag is attached Since it is excluded from the target, it is possible to exclude the moving body with the wireless tag erroneously detected by the detecting means due to, for example, reflection of the wireless signal from the target for specifying the moving direction, and it is necessary to specify the moving direction. The moving direction of the moving body can be reliably identified.

It is a conceptual diagram of the movement direction specific system at the time of applying to goods storage / exit management. It is the block diagram which showed the electrical structure of the moving direction specific system functionally conceptually. It is the table | surface which illustrated the information stored in the state transition table. It is the table | surface which illustrated the information stored in the object list. It is a flowchart of a moving direction specific process. It is the conceptual diagram which illustrated transmission / reception of the signal between the detection part and wireless tag in a detection process. It is a flowchart of a detection process. It is the conceptual diagram which showed the relationship between the detectable range and the reading effective distance s. FIG. 4 is a state transition diagram showing transitions of detection states of wireless tags described by the state transition table of FIG. 3.

  Exemplary embodiments of a moving direction specifying system and a moving direction specifying program according to the present invention will be described below in detail with reference to the accompanying drawings. However, the present invention is not limited by this embodiment. In addition, the application target of the moving direction specifying system and the moving direction specifying program according to the present invention is arbitrary, and can be applied to, for example, goods entering / exiting management or human entrance / exit management, but in the following embodiments, An example in which the present invention is applied to article storage management will be described.

(Constitution)
First, the configuration of the moving direction specifying system will be described. FIG. 1 is a conceptual diagram of a moving direction specifying system when applied to goods storage / exit management, and FIG. 2 is a block diagram functionally conceptually showing the electrical configuration of the moving direction specifying system. For example, as shown in FIG. 1, when an article is loaded and unloaded on a forklift or AGV (Automatic Guided Vehicles), the moving direction specifying system 1 is used to specify the moving direction of the article as a moving body. It is done.

  As shown in FIG. 2, the moving direction specifying system 1 includes a wireless tag 2 and a moving direction specifying device 3.

(Configuration-wireless tag)
The wireless tag 2 is attached to a moving body whose moving direction is to be specified. The specific configuration of the wireless tag 2 is arbitrary, and for example, a known wireless tag such as a passive or active RFID tag or a Wi-Fi tag can be used. The wireless tag 2 stores various information such as a wireless tag ID for uniquely identifying the wireless tag 2 and performs communication with an antenna 4a described later.

(Configuration-moving direction specifying device)
The moving direction specifying device 3 is for specifying the moving direction of the moving body to which the wireless tag 2 is attached by communicating with the wireless tag 2. This moving direction specifying device 3 is configured by connecting a detection unit 4, a speed measurement unit 5, a control unit 6, and a storage unit 7 through a wireless or wired communication line 8 so that they can communicate with each other.

(Configuration-Moving direction identification device-Detection unit)
The detection unit 4 is detection means for detecting the wireless tag 2 by communicating with the wireless tag 2. As shown in FIG. 1, the detection unit 4 is arranged at a plurality of positions along the moving direction of the moving body. In the present embodiment, as shown in FIG. 1, there are two detection units 4 (the left detection unit 4 in FIG. 1 is set as the detection unit 4A, and the right detection unit 4 is set as the detection unit 4B). This will be described as an example.

  As shown in FIG. 2, the detection unit 4 includes an antenna 4a and a detection processing unit 4b. The antenna 4a is a communication unit that performs communication with the wireless tag 2 within a detectable range (a range indicated by a dotted line in FIG. 1). The detectable range is a range in which the antenna 4a can receive a signal transmitted from the wireless tag 2. Although FIG. 1 illustrates the case where the detectable range of the detection unit 4A and the detectable range of the detection unit 4B overlap, the respective detection units 4 are arranged so that these detectable ranges do not overlap. Also good. The detection processing unit 4b detects the wireless tag 2 based on communication between the wireless tag 2 and the antenna 4a. Details of processing executed by the detection unit 4 will be described later.

(Configuration-Moving direction identification device-Speed measurement unit)
The speed measuring unit 5 is speed measuring means for measuring the moving speed of the moving body. The speed measuring unit 5 outputs a measured value of the moving speed of the moving body to the control unit 6. As the speed measuring unit 5, a known speed measuring means such as a speed gun can be used. Or you may make it acquire movement speed information by radio | wireless from the forklift and AGV which convey the articles | goods as a mobile body.

(Configuration-Moving direction identification device-Control unit)
The control unit 6 is a control unit that controls each unit of the moving direction specifying system 1. Specifically, the control unit 6 includes a CPU, various programs that are interpreted and executed on the CPU (including a basic control program such as an OS and an application program that is activated on the OS and realizes a specific function), and The computer includes an internal memory such as a RAM for storing programs and various data. In particular, the moving direction specifying program according to the present embodiment is substantially installed in the moving direction specifying system 1 via an arbitrary storage medium or network, thereby substantially configuring each function of the control unit 6.

  The control unit 6 includes a moving direction specifying unit 6a. The moving direction specifying unit 6a is moving direction specifying means for specifying the moving direction of the moving body. Details of the processing executed by the control unit 6 will be described later.

(Configuration-storage unit)
The storage unit 7 is a recording unit that records a program and various data necessary for the operation of the moving direction specifying system 1, and is configured using, for example, a hard disk (not shown) as an external storage device. However, any other recording medium including a magnetic recording medium such as a magnetic disk or an optical recording medium such as a DVD or a Blu-ray disk can be used instead of or together with the hard disk.

  The storage unit 7 includes a state transition table 7a and a target list 7b.

  The state transition table 7 a is a table that stores information for specifying the transition of the detection state of the wireless tag 2 in each of the detection units 4 arranged at a plurality of positions, and is stored in the storage unit 7 in advance. Here, the “detection state” of the wireless tag 2 is that the wireless tag 2 is newly detected by any of the detection units 4 or the wireless tag 2 detected by any of the detection units 4 disappears. Transition sequentially using as a trigger. In the following description, the fact that the wireless tag 2 is newly detected by any one of the detection units 4 and the disappearance of the wireless tag 2 detected by any one of the detection units 4 is collectively referred to as an “event”. And FIG. 3 is a table illustrating information stored in the state transition table 7a. As shown in FIG. 3, information indicating the “current detection state” (for example, “Initial” “A”) is stored on the vertical axis of the state transition table 7a, and “occurrence event” is displayed on the horizontal axis. Information to be identified (for example, “newly detected by the detection unit A” or the like) is stored. A character representing a detection state that should transition from the current detection state to the next when each event occurs at each position where the “current detection state” on the vertical axis and the “occurring event” on the horizontal axis intersect. (For example, “A” or the like when “current detection state” is “Initial” and “occurrence event” is “newly detected by detection unit A”). Details of the processing based on the state transition table 7a will be described later.

  The target list 7b stores information for specifying the wireless tag 2 that is a target for specifying the moving direction. FIG. 4 is a table illustrating information stored in the target list 7b. As shown in FIG. 4, information corresponding to the items “wireless tag ID”, “final detection time”, and “final detection state” is stored in association with each other in the target list 7b. The information stored corresponding to the item “wireless tag ID” is identification information for uniquely identifying the wireless tag 2 (for example, “0101” in FIG. 4). This identification information is stored in advance in each wireless tag 2, and when the detection unit 4 communicates with the wireless tag 2, it is acquired from the wireless tag 2 by the detection unit 4 and stored in the target list 7b. The information stored corresponding to the item “final detection time” is information for specifying the time when the wireless tag 2 was last detected by any of the detection units 4 (in FIG. 4, for example, “2010/01 / 22 12:00:30 "). This information is stored in the target list 7b by the detection unit 4 when the detection unit 4 communicates with the wireless tag 2, for example. The information stored corresponding to the item “final detection state” is information for specifying the detection state of the wireless tag 2 at the time when the wireless tag 2 was last detected by any of the detection units 4. In the state transition table 7a in FIG. 3, the same information as the character used to represent the detection state is stored (for example, “Aa” in FIG. 4).

(Processing-Moving direction identification processing)
Next, processing performed in the movement direction specifying system 1 configured as described above will be described. FIG. 5 is a flowchart of the movement direction specifying process. This moving direction specifying process is activated when the moving direction specifying device 3 is powered on, for example.

  When the moving direction specifying process is activated, the detection processing unit 4b of each detection unit 4 executes the detection process (SA1).

(Processing-Detection processing)
Here, the detection process will be described. FIG. 6 is a conceptual diagram illustrating transmission / reception of signals between the detection unit 4 and the wireless tag 2 in the detection process. As shown in FIG. 6, in the detection process, the detection unit 4 transmits a read request signal a predetermined number of times within the read request time t. On the other hand, each wireless tag 2 transmits a response signal when receiving a read request signal. The detection unit 4 determines whether or not the wireless tag 2 has been detected in accordance with the number of responses received from the wireless tag 2.

  FIG. 7 is a flowchart of the detection process. When the detection process is activated, the detection processing unit 4b transmits a read request signal from the antenna 4a (SB1). This read request signal is a signal for requesting the wireless tag 2 to transmit a response signal including predetermined information such as a wireless tag ID.

  Subsequently, the detection processing unit 4b determines whether or not a response signal is received from the wireless tag 2 as a response to the read request signal transmitted in SB1 (SB2). For example, the detection processing unit 4b determines whether or not a response signal including information such as a wireless tag ID is received from the wireless tag 2 via the antenna 4a.

  As a result, when it is determined that a response signal has been received (SB2, Yes), the detection processing unit 4b adds one response number indicating the number of times the response signal has been received from the wireless tag 2 (SB3). The number of responses is assumed to be stored in, for example, a RAM (not shown) of the detection unit 4 in association with the wireless tag ID of each wireless tag 2.

  After the process of SB3, or when it is determined that the response signal is not received in SB2 (SB2, No), has the detection request unit 4b elapsed since the start of the transmission of the read request signal? It is determined whether or not (SB4). The specific value of the read request time t is arbitrary, for example, 1 second.

  As a result, when it is determined that the read request time t has not elapsed since the start of transmission of the read request signal (SB4, No), the detection processing unit 4b returns to SB1 and transmits the read request signal from the antenna 4a. To continue.

  On the other hand, if it is determined that the read request time t has elapsed since the start of transmission of the read request signal (SB4, Yes), the detection processing unit 4b calculates the required response count R (SB5). Here, the required response number R is a response signal from the wireless tag 2 that is a reference when the detection unit 4 determines that the wireless tag 2 has been detected when the reading request signal is transmitted from the detection unit 4 a predetermined number of times. The number of times received. Reading when the detection unit 4 transmits a read request signal to the wireless tag 2 and receives a response signal from the wireless tag 2 r times the number of times the detection unit 4 transmits the read request signal during the read request time t When the accuracy is a%, the required response number R is calculated as R = r × a / 100. For example, when r = 8 times and a = 75%, R = 8 × 75/100 = 6 times.

  Subsequently, the detection processing unit 4b causes the speed measuring unit 5 to measure the moving speed of the moving body, and determines whether or not the measured moving speed v of the moving body is larger than the standard speed v0 (SB6). The standard speed v0 is a reference speed for determining whether or not the correction of the required response number R calculated in SB5 is necessary, and when the distance that the moving body moves within the detectable range is the reading effective distance s, Calculated as v0 = s / t. For example, when the reading request time t = 1 second and the reading effective distance s = 2 m, v0 = 2/1 = 2 m / s. FIG. 8 is a conceptual diagram showing the relationship between the detectable range and the effective reading distance s. As shown in FIG. 8, the standard speed v0 represents the maximum speed at which the moving body can remain within the detectable range during the read request time t.

  Returning to FIG. 7, when it is determined that the moving speed v of the moving body is larger than the standard speed v0 (SB6, Yes), the detection processing unit 4b responds to the moving body speed v measured by the speed measuring unit. The response required number of times R is corrected (SB7). For example, the detection processing unit 4b calculates the corrected required response number R ′ as R ′ = R × v0 / v. For example, when R = 6 times, v0 = 2 m / s, and v = 4 m / s, R = 3 times.

  After the process of SB7, or when it is determined in SB6 that the moving speed v of the moving body is not greater than the standard speed v0 (v0 or less) (SB6, No), the detection processing unit 4b returns the response stored in the RAM. Referring to the number of times, it is determined whether or not the number of responses that received the response signal from the wireless tag 2 is equal to or greater than the required response number R (or the required response number R ′ after correction when corrected in SB7) (SB8) . As a result, when the number of responses received from the wireless tag 2 is equal to or greater than the required response number R (SB8, Yes), the detection processing unit 4b detects the wireless tag 2 (SB9), and enters the main routine. Return.

  On the other hand, when the number of responses received from the wireless tag 2 is not equal to or greater than the required response number R (when the response number received from the wireless tag 2 is less than the required response number R) (SB8, No), detection The processing unit 4b returns to the main routine without detecting the wireless tag 2.

  For example, in FIG. 6, consider the case where the required response number R = 6 and the standard speed v0 = 2 m / s. In addition, the moving speed vA of the wireless tag A in FIG. 6 is 2 m / s, the response frequency of the wireless tag A is 7 times, the moving speed vB of the wireless tag B is 4 m / s, the response frequency of the wireless tag B is 4 times, It is assumed that the moving speed vA of the tag C is 1.5 m / s, and the number of responses of the wireless tag C is two. In this case, for the wireless tag A, since the moving speed vA is 2 m / s and not greater than v0, the detection processing unit 4b does not correct the response required number R. Therefore, since the number of responses of the wireless tag A is 7, which is 6 times the required response number R, it is assumed that the detection processing unit 4b has detected the wireless tag A. For the wireless tag B, since the moving speed vB is 4 m / s, which is larger than v0, the detection processing unit 4b corrects the required response count R. In this case, the required response number R ′ after correction is R ′ = R × v0 / vB = 6 × 2/4 = 3. Accordingly, the number of responses of the wireless tag B is 4 times, which is 3 times or more of the response required number R ′ after correction, and therefore it is assumed that the detection processing unit 4b has detected the wireless tag B. For the wireless tag C, the moving speed vC is 1.5 m / s, which is not greater than v0, so the detection processing unit 4b does not correct the required response count R. Therefore, since the number of responses of the wireless tag C is 2 and less than the required response number R, it is assumed that the detection processing unit 4b has not detected the wireless tag C.

  Returning to FIG. 5, after the detection processing unit 4b executes the detection process in SA1, the moving direction specifying unit 6a determines whether or not the wireless tag 2 is detected by the detection processing unit 4b (SA2).

  As a result, when it is determined that the wireless tag 2 is detected by the detection processing unit 4b (SA2, Yes), the movement direction specifying unit 6a acquires the wireless tag ID of the detected wireless tag 2 from the detection unit 4, and the target The last detection time associated with the acquired wireless tag ID in the list 7b is updated (SA3).

  After the process of SA3 or when the movement direction identification unit 6a determines in SA2 that the wireless tag 2 has not been detected by the detection processing unit 4b (SA2, No), the movement direction identification unit 6a is based on the detection result in SA1. It is determined whether an event has occurred (SA4). That is, it is determined whether or not the wireless tag 2 is newly detected in any of the detection units 4 and whether or not the wireless tag 2 detected in any of the detection units 4 has disappeared.

  As a result, when the movement direction specifying unit 6a determines that an event has occurred (SA4, Yes), that is, when any of the detection units 4 newly detects the wireless tag 2, or any of the detection units 4 When the wireless tag 2 detected in step 3 disappears, the moving direction specifying unit 6a refers to the target list 7b and associates with the wireless tag ID of the wireless tag 2 in which the event has occurred and is stored in the target list 7b. The detection state is specified as the current detection state, and the detection state transition of the wireless tag 2 in each detection unit 4 is specified based on the state transition table 7a (SA5).

  FIG. 9 is a state transition diagram showing the transition of the detection state of the wireless tag 2 described by the state transition table 7a of FIG. In FIG. 9, “A +” is an event “newly detected by the detection unit A”, “A−” is an event “disappearing from the detection unit A”, “B +” is an event “newly detected by the detection unit B”, “ "B-" indicates that the event "disappearing from the detection unit B" has occurred.

  For example, in the initial state “Initial” when the moving direction specifying process is started, when the event “newly detected by the detecting unit A” occurs (the wireless tag 2 is within the detectable range from the detectable range of the detecting unit 4A) The movement direction specifying unit 6a specifies that the detection state transitions to “A”.

  In the detection state “A”, when the event “new detection by the detection unit B” occurs (the wireless tag 2 enters the detectable range from outside the detectable range of the detection unit 4B, the detection unit 4A and the detection The movement direction specifying unit 6a specifies that the detection state transitions to “AB”. In the detection state “A”, when the event “disappears from the detection unit A” occurs (when the wireless tag 2 goes out of the detection range of the detection unit 4A), the movement direction specification unit 6a Specifies that the detection state transitions to “Aa”. Further, in the detection state “A”, when the event “disappears from the detection unit A” and the event “new detection by the detection unit B” occur simultaneously (the wireless tag 2 is within the detectable range of the detection unit 4A) If the detection unit 4B enters the detectable range from outside the detectable range at the same time, the movement direction specifying unit 6a may specify that the detection state transitions to “AaB”.

  In addition, in the detection state “AB”, when the event “disappearance from the detection unit A” occurs (the wireless tag 2 has moved out of the detection range of the detection unit 4A, the detection unit 4B can detect If it remains within the range), the moving direction specifying unit 6a specifies that the detection state transitions to “AaB”. In addition, in the detection state “AB”, when the event “disappears from the detection unit B” occurs (the wireless tag 2 has moved out of the detection range of the detection unit 4B, but can be detected by the detection unit 4A. If it remains within the range), the moving direction specifying unit 6a specifies that the detection state transitions to “A”.

  In addition, in the detection state “Aa”, when the event “newly detected by the detection unit A” occurs (when the wireless tag 2 enters the detectable range from outside the detectable range of the detection unit 4A), the moving direction is specified. The unit 6a specifies that the detection state transitions to “A”. In addition, in the detection state “Aa”, when the event “new detection by the detection unit B” occurs (after the wireless tag 2 goes out of the detection range of the detection unit 4A, the detection unit 4B When entering the detectable range), the moving direction specifying unit 6a specifies that the detection state transitions to “AaB”.

  In addition, in the detection state “AaB”, when the event “new detection by the detection unit A” occurs (the wireless tag 2 enters the detectable range from outside the detectable range of the detection unit 4A, the detection unit 4A and When the detection unit 4B is located in the overlapping region of the detectable range), the movement direction specifying unit 6a specifies that the detection state transitions to “AB”. Further, in the detection state “AaB”, when the event “disappears from the detection unit B” occurs (when the wireless tag 2 goes out of the detection range of the detection unit 4B), the wireless tag 2 is detected. From the outside of the detectable range of the part 4A, it is considered that the part has entered the detectable range of the detecting part 4A and moved out of the detectable range of the detecting part 4B through the detectable range of the detecting part 4B. The direction specifying unit 6a specifies that the detection state transitions to “movement direction specification (direction from the detection unit A toward the detection unit B)”.

  Note that, in the initial state “Initial” when the moving direction specifying process is started, the event “newly detected by the detecting unit B” occurs (the wireless tag 2 is within the detectable range from the detectable range of the detecting unit 4B). Also, the movement direction specifying unit 6a refers to the state transition table 7a and sequentially specifies transitions according to the event that has occurred.

  Returning to FIG. 5, the moving direction specifying unit 6a determines whether or not the detection state of the wireless tag 2 after the transition specified by the moving direction specifying unit 6a in SA5 is “moving direction specified” (SA6). As a result, when the detection state of the wireless tag 2 after the transition specified by the movement direction identification unit 6a in SA5 is “movement direction identification” (SA6, Yes), the movement direction identification unit 6a detects the detection specified in SA5. When the movement direction corresponding to the state (the detection state is “movement direction specification (direction from detection unit A toward detection unit B)”), the detection state is “movement direction specification” In the case of (the direction from the detection unit B to the detection unit A), the “direction from the detection unit 4B to the detection unit 4A” is set as the moving direction of the moving object to which the wireless tag 2 is attached. For example, the information is output via a network (not shown) to a management system (not shown) for managing the entry / exit of articles (SA7).

  After that, the moving direction specifying unit 6a deletes the wireless tag ID of the wireless tag 2 specifying the moving direction and the information stored in the target list 7b in association with the wireless tag ID from the target list 7b (SA8). .

  In SA6, when the detection state of the wireless tag 2 after the transition specified by the moving direction specifying unit 6a in SA5 is not “moving direction specifying” (No in SA6), the moving direction specifying unit 6a specifies the moving direction. The final detection state stored in the target list 7b in association with the wireless tag ID of the wireless tag 2 is updated to the detection state after the transition specified in SA5 (SA9).

  In SA4, when the movement direction specifying unit 6a determines that no event has occurred (SA4, No), that is, no wireless tag 2 is newly detected in any of the detection units 4, and the detection unit 4 When none of the detected wireless tags 2 disappears, the moving direction specifying unit 6a refers to the target list 7b, and the wireless tags 2 whose final detection state is “Aa” or “Bb” (that is, all the detecting units 4 The presence / absence of the wireless tag 2) not detected is determined (SA10).

  As a result, when there is a wireless tag 2 whose final detection state is “Aa” or “Bb” (SA10, Yes), the moving direction specifying unit 6a corresponds to the item “final detection time” in the target list 7b. Based on the stored information, it is determined whether or not a predetermined time has passed since the last detection time of the wireless tag 2 whose final detection state is “Aa” or “Bb” (SA11). For example, if the “certain time” is 15 seconds and the current time is January 22, 2010, 12 hours, 1 minute, 0 seconds, in the example of FIG. 3, the wireless tags 2 with the wireless tag IDs “0101” and “0102”. Is determined that 15 seconds or more have elapsed since the last detection time. On the other hand, for the wireless tags 2 with the wireless tag IDs “0103” and “0104”, it is determined that 15 seconds or more have not passed since the last detection time.

  Returning to FIG. 5, when the movement direction specifying unit 6a determines that a predetermined time or more has passed since the last detection time of the wireless tag 2 whose final detection state is “Aa” or “Bb” (SA11, Yes), the movement The direction specifying unit 6a displays the wireless tag ID of the wireless tag 2 determined to have passed a predetermined time from the last detection time and the information stored in the target list 7b in association with the wireless tag ID as the target list. It deletes from 7b (SA12), and excludes the mobile body to which the wireless tag 2 is attached from the identification target of the movement direction.

  After the process of SA8, SA9, or SA12, when the movement direction specifying unit 6a determines in SA10 that there is no wireless tag 2 whose final detection state is “Aa” or “Bb” (SA10, No), or movement in SA11 When the direction specifying unit 6a determines that a predetermined time or more has not elapsed since the last detection time of the wireless tag 2 whose final detection state is “Aa” or “Bb” (SA11, No), the moving direction specifying unit 6a It is determined whether or not the processing from SA4 to SA12 has been performed for all the wireless tags 2 whose wireless tag IDs are stored in the list 7b (SA13).

  As a result, when the processing from SA4 to SA12 is not performed for all the wireless tags 2 whose wireless tag IDs are stored in the target list 7b (SA13, No), the movement determination unit returns to SA4, and the target list 7b The processing from SA4 to SA12 is repeated until the processing from SA4 to SA12 is performed for all the wireless tags 2 in which the wireless tag IDs are stored.

  On the other hand, when the processing from SA4 to SA12 is performed for all the wireless tags 2 whose wireless tag IDs are stored in the target list 7b (SA13, Yes), the processing returns to SA1 and the detection processing unit 4b of each detection unit 4 A detection process is executed (SA1).

(effect)
As described above, according to the present embodiment, the moving direction of the moving body is specified based on the transition of the detection state of the wireless tag 2 in each detection unit 4 arranged at a plurality of positions. Even if a sensor for specifying is not separately provided, the moving direction of the moving body can be specified using the wireless tag 2. In particular, since the moving direction of the moving body is specified when the detection state of the wireless tag 2 in each detection unit 4 has undergone a predetermined transition, the erroneous moving direction due to erroneous detection of the wireless tag 2 or the like is specified. Can be avoided, and the moving direction of the moving body can be reliably specified.

  In addition, after the wireless tag 2 is detected by the detection unit 4, when the wireless tag 2 has not been detected by all the detection units 4 and a certain period of time has elapsed, the mobile body to which the wireless tag 2 is attached is Since the moving direction is excluded from the identification target, for example, the moving body with the wireless tag 2 erroneously detected by the detection unit 4 due to reflection of a radio signal or the like can be excluded from the identification target of the movement direction. It is possible to reliably specify the moving direction of the moving body that needs to be specified.

  Further, when the number of times the response signal is received from the wireless tag 2 when the read request signal is transmitted a predetermined number of times is greater than the required number of responses according to the speed of the moving object measured by the speed measuring unit 5, Since the tag 2 is detected, the wireless tag 2 is attached only when the wireless tag 2 is located within the detectable range of the detection unit 4 and the detection unit 4 can reliably receive a response signal from the wireless tag 2. For example, it is possible to reduce the probability of erroneous detection of the wireless tag 2 due to reflection of a wireless signal or the like.

[Modifications to Embodiment]
Although the embodiments of the present invention have been described above, the specific configuration and means of the present invention can be arbitrarily modified and improved within the scope of the technical idea of each invention described in the claims. Can do. Hereinafter, such a modification will be described.

(About problems to be solved and effects of the invention)
First, the problems to be solved by the invention and the effects of the invention are not limited to the above-described contents, and the present invention solves the problems not described above or has the effects not described above. There are also cases where only some of the described problems are solved or only some of the described effects are achieved.

(About distribution and integration)
Further, each of the electrical components described above is functionally conceptual and does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution / integration of each part is not limited to the one shown in the figure, and all or a part thereof may be functionally or physically distributed / integrated in arbitrary units according to various loads and usage conditions. Can be configured. For example, the detection processing unit 4b in each detection unit 4 may be integrated and provided in the control unit 6. Further, the detection unit 4 and the storage unit 7 in the movement direction identification system 1 may be external devices of the movement direction identification system 1.

DESCRIPTION OF SYMBOLS 1 Movement direction identification system 2 Wireless tag 3 Movement direction identification device 4, 4A, 4B Detection part 4a Antenna 4b Detection processing part 5 Speed measurement part 6 Control part 6a Movement direction identification part 7 Storage part 7a State transition table 7b Object list 8 Communication Line

Claims (2)

A moving direction specifying system for specifying a moving direction of a moving body,
A wireless tag attached to the mobile body;
A detecting unit disposed at a plurality of positions along a moving direction of the moving body, and detecting the wireless tag by communicating with the wireless tag ;
A moving direction specifying means for specifying a moving direction of the moving body based on a transition of a detection state of the wireless tag in each of the detecting means arranged at the plurality of positions;
Speed measuring means for measuring the moving speed of the moving body,
The moving direction specifying means is attached to the wireless tag when a certain period of time has passed without the wireless tag being detected by all the detecting means after the wireless tag is detected by the detecting means. Excluding the moving object from the specific object of movement direction;
The detecting means transmits a read request signal;
The wireless tag transmits a response signal when receiving the read request signal,
The detecting means receives the response signal from the wireless tag when the read request signal is transmitted a predetermined number of times, and the number of times required for response according to the speed of the moving body measured by the speed measuring means In this case, it is assumed that the wireless tag is detected.
Moving direction identification system. A moving direction specifying program for causing a computer to specify a moving direction of a moving body,
A detecting step of detecting the wireless tag by communicating with a wireless tag attached to the moving body by detecting means arranged at a plurality of positions along the moving direction of the moving body;
A moving direction specifying step for specifying a moving direction of the moving body based on transition of the detection state of the wireless tag in each of the detecting means arranged at the plurality of positions;
Causing the computer to execute a speed measuring step of measuring the moving speed of the moving body by means of speed measuring means;
In the moving direction specifying step,
After the detection of the wireless tag, if the wireless tag has not been detected by all of the detection means and a certain period of time has elapsed, the mobile body with the wireless tag attached is moved in the moving direction. Exclude from specific target,
In the detecting step,
When the reading request signal is transmitted from the detection unit a predetermined number of times, the number of times the detection unit receives a response signal to the reading request signal from the wireless tag is measured by the speed measurement unit. If the number of responses exceeds the number of times required according to the speed, the wireless tag is assumed to be detected.
Moving direction identification program.

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