JP2007085826A - Article search system and article search program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an article search system and an article search program, allowing to identify the position of an article by only attaching a small-sized RFID, even in an environment in which radio-wave propagation environment is not stable. <P>SOLUTION: A plurality of interrogators 104a to 104i of RFID and a position tag 101, of which the position information is known, are installed in an article position management environment 100; the transmission outputs of interrogating waves from a plurality of interrogators are made to fluctuate, and the detection results for the position tag and an article tag 102, which have been newly detected through the fluctuation portions of the transmission outputs, are accumulated; and the article tag and the position tag which have been detected in duplicate in the detection results are specified. By using the positional information of the position tag, the position of the article is identified. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an article search system and an article search program for specifying an article position in an environment where an article whose position is unspecified by movement is handled.

  A prior invention similar to the present invention will be described.

  Conventionally, in order to detect the position of an object that moves arbitrarily, the object is detected from a plurality of remote sensors, and the position is measured by a triangulation method from the detection status of the object detected by the plurality of sensors. .

  Specifically, if the sensor is a camera, the same article in the captured image of each camera is identified, the direction pointing to the article is calculated from the camera position from the article position and the camera attitude in the captured image, and a known camera The article position is determined by specifying a plurality of directions from the position to the article.

  When using an ultrasonic wave, an ultrasonic oscillator is attached to an article whose position needs to be specified, and the ultrasonic wave is transmitted to the ultrasonic oscillator by signals from radio waves or light from a plurality of ultrasonic receivers arranged at fixed positions. Send oscillation trigger. The time until the receiver receives the ultrasonic wave emitted from the oscillator is measured, and the distance between the receiver and the oscillator is calculated based on the speed of sound. The article position is identified by identifying a plurality of distances from the receiver to the article.

  As in the present invention, in the case of article position detection by a triangulation method using radio waves, a radio wave transmitter is attached to an article (person) as in the invention disclosed in Conventional Example 1 (see Patent Document 1). Equipped with a plurality of receivers placed at fixed positions to receive radio waves transmitted from the radio wave transmitter, and estimate the distance from the receiver to the oscillator based on the intensity of the received radio waves. A method of specifying the position of the article (person) by specifying the distance from a plurality of receivers to the oscillator attached to the article (person) is used. The method of Conventional Example 1 is suitable when there is no practical problem even if the radio wave transmitter is large. This is because, in order to perform transmission of radio waves with a transmitter attached to an article (person), it is necessary to incorporate a power supply unit (battery) for practically supplying transmission power inside the transmitter. . In practice, when a small RFID is used, it is not possible to incorporate a power supply device for transmitting radio waves.

  In Conventional Example 2 (see Patent Document 2) described below, the article position by the triangulation method similar to Conventional Example 1 can be obtained by simply attaching a small passive RFID 1103 to the article 1101 that needs to be searched for a position. An invention for realizing the measurement is disclosed.

  In Conventional Example 2, RFID 1103 attached to an article is detected while changing the transmission intensity of radio waves from a plurality of transmission / reception antennas 1102 at fixed positions. Focusing on the change in the detection state of the article RFID 1103 at each antenna 1102 by changing the intensity of the transmission radio wave from the antenna 1102, the target RFID 1103 can be detected from detectable to undetectable, or detected from undetectable. The distance from the antenna 1102 to the target RFID 1103 can be calculated by storing the intensity of the transmission radio wave at the time and collating it with a table that records the relationship between the transmission radio wave output acquired in advance and the detectable distance of the RFID 1103. It is.

  In the case of the conventional example 2, the spontaneous radio wave transmission from the transmitter (RFID) required in the conventional example 1 is not necessary, and an antenna or a reader is attached to the article 1101 as in the conventional example 2. The distance from the antenna 1102 to the RFID 1103, that is, the distance to the article 1101 can be specified by the transmission output from the antenna 1102, and the position of the article can be specified by triangulation by specifying the plurality of antennas 1102 to the article 1103. I can do it.

Japanese Patent Laid-Open No. 1993-011039 JP 2002-250768 A

  The technique for searching for the position of an article using RFID 1103 disclosed in Conventional Example 2 has a uniform radio wave environment in the environment for searching for the position of the article. The transmission radio wave output from the antenna 1102 acquired in advance and the RFID 1103 It is essential that the relationship between the detectable distances is stable.

  On the other hand, in a search environment for the position of an article such as a general home or office that is the subject of the present invention, shelves and structures are intricately confined in a narrow space, or people and articles move, and articles are irregularly arranged. For example, the radio wave environment that can be placed in the environment for searching for the position of an article is complicated and frequently changes, and the relationship between the radio wave output from the antenna acquired in advance and the detectable distance of the RFID is constant. I can't expect that.

  For this reason, the technique of Conventional Example 3 cannot accurately search for the position of the article.

  Therefore, an object of the present invention is to provide an article search system and an article search program that can reliably search for the position of an article equipped with an RFID even in a situation where the radio wave environment is unstable.

  In order to achieve the above object, the present invention is configured as follows.

According to the first aspect of the present invention, an article ID transmitter / receiver that is attached to an article, receives an interrogation wave, and transmits an identification signal of the article in response, and responds to the interrogation wave and returns its own identification signal. Transmitting the interrogation wave from a plurality of directions to the search transceiver, receiving response transmissions from the article ID transceiver and the search transceiver, and acquiring identification information of the article ID transceiver and the search transceiver One interrogator,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
An identification information database for storing identification information of the article ID transmitter / receiver and the search transmitter / receiver received by the interrogator;
From the history of identification information of the article ID transceiver and the search transceiver stored in the identification information database, a search transceiver having a common detection state is specified for the detection state of the article from a plurality of directions. Article position estimation means for reading position information corresponding to the identified identification information of the search transceiver from the search information database and estimating the position of the article based on the position information corresponding to the read identification information of the search transceiver When,
An article position database for storing information on the estimated article position;
An article search system is provided.

  As a result, no matter how the radio wave environment changes, in the situation where the interrogator can receive a response from the item ID transmitter / receiver, it can also receive a response from the search transmitter / receiver arranged in the nearby radio wave environment. Search transmission / reception that is close to the article ID transmitter / receiver by specifying a search transmitter / receiver that is highly common to the response reception status of the article ID transmitter / receiver from the response reception status of the article ID transmitter / receiver and the search transmitter / receiver from multiple directions. The position information of the article ID transmitter / receiver can be estimated using the position information of the search transmitter / receiver.

According to the third aspect of the present invention, an article ID transmitter / receiver that is attached to an article, receives an interrogation wave, and transmits an identification signal of the article in response, and responds to the interrogation wave and returns its own identification signal. The interrogation wave is transmitted from a plurality of directions to the search transceiver, the response transmission from the article ID transceiver and the search transceiver is received, and the identification information of the article ID transceiver and the search transceiver is acquired. A plurality of interrogators arranged such that their detection ranges overlap within an area for managing the position of the article,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
The interrogator control means receives the response signals from the article ID transceiver and the search transceiver while gradually increasing or decreasing the transmission output of the interrogation wave from each interrogator. An identification information database for storing identification information of the received article ID transceiver and search transceiver;
Identification of an article ID transmitter and a search transceiver that can be detected or cannot be detected according to a change in transmission output of the interrogation wave from identification information histories of the article ID transmitter and the search transceiver in the identification information database. Extract the information history, and identify the search transceiver that became detectable or undetectable at the same time or near the same time for the specific article ID transceiver that became detectable or undetectable from the extracted identification information history In addition, the search transmitter / receiver that is detected in common by a plurality of interrogators among the specified search transmitter / receivers, and that the detectable range can be narrowed down to one region from the overlapping degree of the common detection ranges of the plurality of interrogators Article position estimation means having the position of the article as the article position;
An article position database for storing information on the estimated article position;
An article search system is provided.

  Thereby, the identification information of the article ID transmitter / receiver and the search transmitter / receiver can be obtained by the interrogation wave from the interrogator in a plurality of directions arranged in the area for managing the article position, and the interrogation wave is transmitted from the interrogator. By transmitting the interrogation wave while increasing or decreasing the intensity, changes in the identification information of the article ID transmitter / receiver and the search transmitter / receiver can be accumulated in detail. Thereby, the commonality of the detection states of the article ID transceiver and the search transceiver can be specified in more detail, that is, the article position can be estimated in detail.

According to the fourth aspect of the present invention, an article ID transmitter / receiver that is attached to an article and receives the interrogation wave and responds and transmits the identification signal of the article, and responds to the interrogation wave and returns its own identification signal. The interrogation wave is transmitted from a plurality of directions to the search transceiver, the response transmission from the article ID transceiver and the search transceiver is received, and the identification information of the article ID transceiver and the search transceiver is acquired. A plurality of interrogators arranged so that their detection ranges overlap in an area for managing the position of the article,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
The transmission output of the interrogation wave from each interrogator is gradually changed by the interrogator control means while receiving response signals from the article ID transceiver and the search transceiver, and the obtained An identification information database for storing identification information of the article ID transceiver and the search transceiver;
Identification of an article ID transmitter and a search transceiver that can be detected or cannot be detected according to a change in transmission output of the interrogation wave from identification information histories of the article ID transmitter and the search transceiver in the identification information database. Extract the information history, and identify the search transceiver that became detectable or undetectable at the same time or near the same time for the specific article ID transceiver that became detectable or undetectable from the extracted identification information history Position information of a plurality of search transceivers that can be specified in common among the search transceivers specified by the plurality of interrogators, and the plurality of searches specified above with the specific article ID transmitter / receiver Interpolate and estimate the article position based on the positional relationship between the article ID transmitter / receiver, multiple search transmitter / receivers, and interrogator estimated from the difference in the detection time change of the transmitter / receiver. And an article position estimating means,
An article position database for storing information on the estimated article position;
An article search system is provided.

  As a result, the arrangement interval of the search transceivers is large, and even when the article is placed between the plurality of search transceivers, the interpolation calculation using the position information of the plurality of search transceivers provides high accuracy. The position of the article ID transmitter / receiver can be estimated.

According to the fifth aspect of the present invention, an article ID transmitter / receiver that is attached to an article, receives an interrogation wave, and transmits an identification signal of the article in response, and responds to the interrogation wave and returns its own identification signal. The interrogation wave is transmitted from a plurality of directions to the search transceiver, the response transmission from the article ID transceiver and the search transceiver is received, and the identification information of the article ID transceiver and the search transceiver is acquired. An interrogator mounted on a moving body that moves within an area for managing the position of the article;
While transmitting the interrogation wave having a constant intensity from the interrogator while the moving body is moving, receiving the response signal from the article ID transmitter / receiver and the search transceiver, the obtained article ID transmitter / receiver and the search transceiver An identification information database for storing identification information of
The identification information history of the article ID transmitter and the search transceiver that can be detected or cannot be detected according to the movement of the mobile body from the identification information history of the article ID transmitter and the search transceiver in the identification information database. From the extracted identification information history, a search transceiver that can be detected or cannot be detected at the same time or at a close time is specified for a specific article ID transmitter that can or cannot be detected. Among the specified search transceivers, the search transceivers that are commonly detected by a plurality of interrogators, and the detectable range can be narrowed down to one region from the overlapping degree of the common detection ranges of the plurality of interrogators. Article position estimating means whose position is the article position;
An article position database for storing information on the estimated article position;
An article search system is provided.

  Accordingly, the article ID transmitter / receiver and the search transmitter / receiver from a plurality of directions can be obtained by transmitting the interrogation wave to the article ID transmitter / receiver and the search transmitter / receiver by the interrogator equipped in the moving body that moves within the region for managing the article position. Since the interrogator moves and transmits the interrogation wave, changes in the identification information of the article ID transmitter / receiver and the search transmitter / receiver can be accumulated in detail. Thereby, the commonality of the detection states of the article ID transceiver and the search transceiver can be specified in more detail, that is, the article position can be estimated in detail.

According to a sixth aspect of the present invention, a computer
Controlling the transmission output of the interrogation wave from the interrogator;
Identification of an article ID transmitter / receiver which is received by the interrogator and which is attached to the article and receives the interrogation wave and transmits the identification signal of the article as a response and a search transceiver which responds to the interrogation wave and returns its own identification signal Storing information in an identification information database;
A search transmitter / receiver having a common detection state is identified and specified with respect to the detection state of the article from a plurality of directions based on the identification information history of the article ID transmitter / receiver and the search transmitter / receiver accumulated in the identification information database. The position information corresponding to the identification information of the search transceiver is read from the search information database that stores the position information of the search transceiver in association with the identification information of the search transceiver, and corresponds to the read identification information of the search transceiver An article search program for executing the step of estimating an article position based on position information to be performed is provided.

  According to the article search system and the article search program of the present invention, since it is not necessary to calculate the distance between the antenna and the article tag based on the radio wave transmission intensity from the antenna, the article ID transmission / reception is performed due to the fluctuation of the radio wave environment in the article search area. Even if the radio wave transmission intensity capable of detecting a detector (for example, an article tag using passive RFID (Radio Frequency Identification) functioning as an example of an article ID transceiver) fluctuates, search transmission / reception in the vicinity of the article ID transceiver By detecting the detection state (detectable / impossible state) of a device (for example, a position tag using a passive RFID functioning as an example of a search transmitter / receiver) from at least one interrogator, the vicinity of the article ID transmitter / receiver The search transceiver can be specified. That is, the position of the article can be determined by using the position information of the search transceiver that can be specified.

  Before describing embodiments of the present invention, various aspects of the present invention will be described below.

According to the first aspect of the present invention, an article ID transmitter / receiver that is attached to an article, receives an interrogation wave, and transmits an identification signal of the article in response, and responds to the interrogation wave and returns its own identification signal. Transmitting the interrogation wave from a plurality of directions to the search transceiver, receiving response transmissions from the article ID transceiver and the search transceiver, and acquiring identification information of the article ID transceiver and the search transceiver One interrogator,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
An identification information database for storing identification information of the article ID transmitter / receiver and the search transmitter / receiver received by the interrogator;
From the history of identification information of the article ID transceiver and the search transceiver stored in the identification information database, a search transceiver having a common detection state is specified for the detection state of the article from a plurality of directions. Article position estimation means for reading position information corresponding to the identified identification information of the search transceiver from the search information database and estimating the position of the article based on the position information corresponding to the read identification information of the search transceiver When,
An article position database for storing information on the estimated article position;
An article search system is provided.

  According to a second aspect of the present invention, there is provided the article search system according to the first aspect, further comprising an operation terminal that extracts the article position information from the article position database by inquiring about the position of the article.

According to the third aspect of the present invention, an article ID transmitter / receiver that is attached to an article, receives an interrogation wave, and transmits an identification signal of the article in response, and responds to the interrogation wave and returns its own identification signal. The interrogation wave is transmitted from a plurality of directions to the search transceiver, the response transmission from the article ID transceiver and the search transceiver is received, and the identification information of the article ID transceiver and the search transceiver is acquired. A plurality of interrogators arranged such that their detection ranges overlap within an area for managing the position of the article,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
The interrogator control means receives the response signals from the article ID transceiver and the search transceiver while gradually increasing or decreasing the transmission output of the interrogation wave from each interrogator. An identification information database for storing identification information of the received article ID transceiver and search transceiver;
Identification of an article ID transmitter and a search transceiver that can be detected or cannot be detected according to a change in transmission output of the interrogation wave from identification information histories of the article ID transmitter and the search transceiver in the identification information database. Extract the information history, and identify the search transceiver that became detectable or undetectable at the same time or near the same time for the specific article ID transceiver that became detectable or undetectable from the extracted identification information history In addition, the search transmitter / receiver that is detected in common by a plurality of interrogators among the specified search transmitter / receivers, and that the detectable range can be narrowed down to one region from the overlapping degree of the common detection ranges of the plurality of interrogators Article position estimation means having the position of the article as the article position;
An article position database for storing information on the estimated article position;
An article search system is provided.

According to the fourth aspect of the present invention, an article ID transmitter / receiver that is attached to an article and receives the interrogation wave and responds and transmits the identification signal of the article, and responds to the interrogation wave and returns its own identification signal. The interrogation wave is transmitted from a plurality of directions to the search transceiver, the response transmission from the article ID transceiver and the search transceiver is received, and the identification information of the article ID transceiver and the search transceiver is acquired. A plurality of interrogators arranged so that their detection ranges overlap in an area for managing the position of the article,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
The transmission output of the interrogation wave from each interrogator is gradually changed by the interrogator control means while receiving response signals from the article ID transceiver and the search transceiver, and the obtained An identification information database for storing identification information of the article ID transceiver and the search transceiver;
Identification of an article ID transmitter and a search transceiver that can be detected or cannot be detected according to a change in transmission output of the interrogation wave from identification information histories of the article ID transmitter and the search transceiver in the identification information database. Extract the information history, and identify the search transceiver that became detectable or undetectable at the same time or near the same time for the specific article ID transceiver that became detectable or undetectable from the extracted identification information history Position information of a plurality of search transceivers that can be specified in common among the search transceivers specified by the plurality of interrogators, and the plurality of searches specified above with the specific article ID transmitter / receiver Interpolate and estimate the article position based on the positional relationship between the article ID transmitter / receiver, multiple search transmitter / receivers, and interrogator estimated from the difference in the detection time change of the transmitter / receiver. And an article position estimating means,
An article position database for storing information on the estimated article position;
An article search system is provided.

According to the fifth aspect of the present invention, an article ID transmitter / receiver that is attached to an article, receives an interrogation wave, and transmits an identification signal of the article in response, and responds to the interrogation wave and returns its own identification signal. The interrogation wave is transmitted from a plurality of directions to the search transceiver, the response transmission from the article ID transceiver and the search transceiver is received, and the identification information of the article ID transceiver and the search transceiver is acquired. An interrogator mounted on a moving body that moves within an area for managing the position of the article;
While transmitting the interrogation wave having a constant intensity from the interrogator while the moving body is moving, receiving the response signal from the article ID transmitter / receiver and the search transceiver, the obtained article ID transmitter / receiver and the search transceiver An identification information database for storing identification information of
The identification information history of the article ID transmitter and the search transceiver that can be detected or cannot be detected according to the movement of the mobile body from the identification information history of the article ID transmitter and the search transceiver in the identification information database. From the extracted identification information history, a search transceiver that can be detected or cannot be detected at the same time or at a close time is specified for a specific article ID transmitter that can or cannot be detected. Among the specified search transceivers, the search transceivers that are commonly detected by a plurality of interrogators, and the detectable range can be narrowed down to one region from the overlapping degree of the common detection ranges of the plurality of interrogators. Article position estimating means whose position is the article position;
An article position database for storing information on the estimated article position;
An article search system is provided.

According to a sixth aspect of the present invention, a computer
Controlling the transmission output of the interrogation wave from the interrogator;
Identification of an article ID transmitter / receiver which is received by the interrogator and which is attached to the article and receives the interrogation wave and transmits the identification signal of the article as a response and a search transceiver which responds to the interrogation wave and returns its own identification signal Storing information in an identification information database;
A search transmitter / receiver having a common detection state is identified and specified with respect to the detection state of the article from a plurality of directions based on the identification information history of the article ID transmitter / receiver and the search transmitter / receiver accumulated in the identification information database. The position information corresponding to the identification information of the search transceiver is read from the search information database that stores the position information of the search transceiver in association with the identification information of the search transceiver, and corresponds to the read identification information of the search transceiver An article search program for executing the step of estimating an article position based on position information to be performed is provided.

  Next, embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1A shows an environment in which the position of an article such as a home or office is managed by the article search system according to the first exemplary embodiment of the present invention (a structure of a room partitioned by a partition as a specific example. This is simply referred to as “article location management environment”).

  On the floor of the article position management environment 100, position tags 101 (x, y) using passive RFID (Radio Frequency Identification), which plays a role as an example of a search transmitter / receiver, are arranged at predetermined intervals, for example, on the floor surface. In addition, the RFID interrogators 104 a to 104 i are also arranged on the ceiling at predetermined intervals, for example, and the computer 105 is installed at an arbitrary position inside the article position management environment 100 or outside the article position management environment 100.

  The computer 105 includes an interrogator control means 201, an identification information database 202, a position specifying information database 204 as an example of a search information database, an article position estimation means 203, an article position information database 205, a database access means 208, and an operation terminal 206. Implement a program that allows to function.

  Further, in the article position management environment 100, there are articles attached with article tags 102a to 102c using a passive RFID functioning as an example of the person 103 as a moving object and the article ID transmitter / receiver.

  For the convenience of explanation, the position tag 101 (x, y) is indicated by a subscript in which the horizontal direction is an x value and the vertical direction is a y value among the numbers indicated by the vertical and horizontal auxiliary lines indicated by a one-dot chain line in FIG. 1A. They are distinguished and arranged on the floor surface of the room 100 at equal intervals vertically and horizontally. In practical use of the article search system according to the first exemplary embodiment of the present invention, it is desirable that the position tag 101 (x, y) is arranged not only on the floor surface but also in a space where articles such as a shelf and a desk can be placed.

  FIG. 2A shows a processing configuration in the computer 105 and a connection state as an article search system.

  The position specifying information database 204 stores in advance position information of all position tags 101 (x, y), that is, position information of 101 (1, 1) to 101 (12, 8).

  The interrogator control means 201 of the computer 105 is connected to all the interrogators 104a to 104i, controls all the interrogators 104a to 104i by the interrogator control means 201, and can respond to the interrogation waves from the interrogators 104a to 104i. The identification information obtained from the correct article tag 102 and the position tag 101 (x, y) is written into the identification information database 202 as necessary.

  The identification information database 202 is connected to the timer 207 and the interrogator control means 201, and the identification information obtained from the article tag 102 and the position tag 101 (x, y) that can respond to the interrogation waves from the interrogators 104a to 104i. Are acquired and stored via the interrogator control means 201.

  The timer 207 is connected to the identification information database 202, sends time information to the identification information database 202, and is used to store the time information together with other information in the identification information database 202 when necessary.

  The article position estimating means 203 is connected to the identification information database 202, the position specifying information database 204, and the article position information database 205, respectively, and estimates the article position from the information stored in the identification information database 202 and the position specifying information database 204. Information on the estimated article position is stored in the article position information database 205.

  The operation terminal 206 is connected to the database access unit 208 and transmits an operator's request operation for article position information to the database access unit 208, while receiving information sent from the database access unit 208 and presenting it to the operator. The method of presentation to the operator is performed through a speaker 206a and a display 206b connected to the computer 105. The operator's request operation for the article position information is performed from an operation I / F such as the keyboard 206c or the microphone 206d.

  The database access unit 208 is connected to the operation terminal 206 and the article position information database 205, and reads out the article position information from the article position information database 205 in response to an operator's request operation for article position information from the operation terminal 206. Send to.

  On the other hand, as shown in FIG. 2B, each interrogator 104 includes an antenna 104-1, a transmission radio wave control means 104-2 connected to the antenna 104-1, and a reception signal processing means connected to the antenna 104-1. 104-3, and an external interface 104-4 to which transmission radio wave control means 104-2 and reception signal processing means 104-3 are connected.

  For transmission of the interrogation wave to the outside of the interrogator 104, the transmission signal oscillated by the transmission radio wave control means 104-2 is transmitted via the antenna 104-1. At this time, the output of the transmission signal generated by the transmission radio wave control unit 104-2 is controlled by control information received from the interrogator control unit 201 via the external I / F 104-4.

  When an interrogation wave is transmitted from the interrogator 104, the position tag 101 (x, y) or article that has response information that is located within the reach of the interrogation wave and that can respond to the interrogation information included in the interrogation wave The tags 102a to 102c transmit ID information in response to the transmitted interrogation wave. Reception of the ID information transmitted from the position tag 101 (x, y) or the article tags 102a to 102c in response to the transmitted interrogation wave is received by the reception signal processing means 104-3 via the antenna 104-1. The ID information received by the reception signal processing unit 104-3 is transmitted to the interrogator control unit 201 via the external I / F 104-4.

  FIG. 2C shows a configuration as an RFID 99 common to the article tag 102 and the position tag 101 (x, y). The RFID 99 includes an antenna 99-1, a transmission signal generation unit 99-2 connected to the antenna 99-1, a transmission voltage generation unit 99-3 connected to the antenna 99-1, and a transmission signal generation unit 99. -IC99-4 connected to -2.

  The operation of the RFID 99 for the interrogation wave transmitted from the interrogator 104 will be described. First, the transmission voltage generation means 99-3 generates a drive voltage inside the RFID 99 from the received power of the interrogation wave received by the antenna 99-1. The drive voltage is supplied from the transmission voltage generation means 99-3 to each unit, that is, the transmission signal generation means 99-2 and the IC 99-4 through a voltage supply line indicated by a thin line in FIG. 2C. The IC (IC chip) 99-4 that has started operation by supplying the drive voltage transmits the ID information stored in the built-in memory of the IC 99-4 to the transmission signal generating means 99-2. The transmission signal generating means 99-2 modulates the ID information, superimposes it on the carrier wave of the interrogation wave, and transmits it by the antenna 99-1.

  RFID99 has several types of interrogators and RFID transmission / reception methods such as electromagnetic coupling method (13.56MHz) and radio wave utilization method (UHF, 2.45GHz) depending on the carrier frequency. Even in the system, remote ID information can be responded between interrogators, which is a basic function of RFID, and any method can be applied in the present invention.

  Next, the interrogator control processing flow of the interrogator control means 201 will be described with reference to FIG.

  The interrogator control process starts by starting the computer 105 and starting the article search system.

  When the article search system is activated, the interrogator control means 201 sets the transmission output setting value of the interrogator 104 of each interrogator 104 to a predetermined minimum value in step S300 as an initial setting, and transmits the interrogation wave. As an example, the interrogator 104 is set as the interrogator 104a in FIG. 1A.

  Next, under the control of the interrogator control means 201, the interrogation wave of the transmission output set value is transmitted from the set transmission interrogator 104a (step S301). When there is an article tag 102a to 102c or a position tag 101 (x, y) that can acquire identification information in response to the interrogation wave (step S302), the identification information is under the control of the interrogator control means 201. It accumulates in the identification information database 202 (step S309 and step S310). That is, in step S309, identification information detected by the transmission interrogator 104a at a stage smaller than the current transmission output setting value is read from the identification information database 202 by the interrogator control means 201, and in step S310, the tag detected in step S301. The identification information difference obtained by excluding the identification information read from the identification information database 202 by the interrogator control means 201 in step S309 from the identification information of the identification information database 202 is stored in the identification information database 202 as new identification information. Write by 201.

  When step S302 is No or after step S310, the interrogator control unit 201 changes the transmission interrogator 104 to the next interrogator 104 so as to circulate between the transmission interrogators 104b to 104i (step S302). S304). For example, if the interrogator 104 that transmitted the interrogation wave before step S302 is the interrogator 104a, the next interrogator 104 is changed to the interrogator 104b.

  Next, when the transmission interrogator changed in step S304 goes around 104a to 104i and returns to 104a (when step S305 is Yes), the process proceeds to step S306, and otherwise (ie, transmission question). If the instrument is any one of 104b to 104i, that is, if step S305 is No, unless there is an end command from the operator (as long as step S311 is No), the process returns to step S301 to control the interrogator. Under the control of the means 201, the processing from step S301 to step S304 is repeated. Thus, under the control of the interrogator control means 201, the processing from step S301 to step S304 is repeated for all the transmission interrogators 104a to 104i starting from the transmission interrogator 104a to the transmission interrogator 104i. Become. If step S305 is No and if there is an end command from the operator (step S311 is Yes), the process ends.

  Next, in step S306, the interrogator control means 201 increases the transmission output set value (step S306). At this time, if the changed transmission output setting value exceeds the maximum setting value (when Step S308 is Yes), the process returns to Step S300 unless there is an end command from the operator (Step S312 is No). Then, the interrogator controller 201 returns the transmission output setting value and the transmission interrogator 104 to the initial settings and repeats the above processing. If the transmission output set value is within the maximum set value, the process returns to step S301 unless there is an end command from the operator (as long as step S311 is No). If it is detected in step S312 that an end command has been input from the operator (if step S312 is Yes), the process ends.

  By executing the above processing flow, the article tags 102a to 102c or the position tags are sequentially changed while sequentially changing the transmission output of the interrogation waves from all the interrogators 104a to 104i under the control of the interrogator control means 201. 101 (x, y) can be detected. Further, the identification information of the article tag 102 and the position tag 101 that can be detected at the time of transmission of each interrogation wave can be stored in the identification information database 202 in order by the interrogator control means 201.

  The maximum transmission output of the transmission radio waves from each interrogator 104 is set so that the transmission radio waves from the plurality of interrogators 104 overlap each other in the region where the article position in the article position management environment 100 is desired at the maximum transmission output. To do.

  Here, FIG. 1B schematically shows the state of the transmission wave of the interrogator 104h, and a specific example of a method for setting the transmission output from the interrogator 104h will be described. A concentric closed curve surrounding the interrogator 104h (a closed curve indicated by a dotted line in FIG. 1B) indicates a detectable range of the position tag and the article tag when the transmission intensity is changed from the interrogator 104h.

  The area occupied by the closed curve increases with each increase in the transmission intensity of the interrogation wave. At this time, the transmission output from the interrogator 104h is output in all directions in the same manner, but the propagation of the interrogation wave is blocked by the structural wall or the partition wall by passing through the structural wall or the partition wall. The detectable range of the position tag 101 and the article tag 102 is not necessarily expanded concentrically. For example, even when the transmission output similarly increases, the increase in the detectable range of the position tag 101 and the article tag 102 by passing through the structural wall 100a immediately below the interrogator 104h in FIG. Will be reduced. In order to determine the maximum transmission output from the interrogator 104h in such a radio wave propagation environment, the transmission output is increased, and the interrogators 104d, 104e, 104g arranged around the interrogator 104h are arranged. Maximum transmission output that can be detected by all of the position tags 101 (4, 4), 101 (8, 4), 101 (2, 1), and 101 (10, 1) under each (position) of 104i Determined as output. Similarly, in the interrogator 104d, the position tags 101 (2, 7), 101 (6, 7), 101 (8, 4) at the positions of the interrogators 104a, 104b, 104e, 104g, and 104h adjacent to the interrogator 104d. ), 101 (2, 1), and 101 (6, 1) can be detected as the maximum transmission output. In this case, the triangular area formed by the adjacent interrogators 104 becomes a detectable area that is tripled by the maximum transmission output from the three interrogators 104.

  In this manner, the position of the article can be specified by determining the maximum transmission output of the area sandwiched between the interrogators 104 so that the detection areas of the interrogators 104 in the interrogation wave overlap. A method for specifying the article position by determining the maximum transmission output from each interrogator 104 as described above will be described below.

  In FIG. 4A, according to the interrogator control processing flow of the interrogator control means 201, the interrogator 104 circulates between 104a to 104i, and the transmission output of the interrogator 104 is increased in increments of 50mW from 50mW. A specific example of recorded information in the identification information database 202 detected while being shown.

  In the figure, as specific examples of the identification information sequentially stored in the identification information database 202 by the interrogator control process, the interrogators 104a and 104b when the detection by the interrogators 104a to 104i is sequentially performed with a transmission output of 50 mW. , 104c is shown as a specific example. Further, a specific example of the identification information when the interrogator 104i detects the article ID 102c when the interrogators 104a to 104i are sequentially detected with the transmission output 100mW obtained by increasing the transmission output by 50mW is shown. Further, a specific example of identification information when 104e detects the article ID 102c when the interrogators 104a to 104i sequentially perform detection with the transmission output 150mW obtained by further increasing the transmission output by 50mW is shown. In addition, when the transmission output is further increased by 50 mW and the interrogators 104a to 104i are sequentially detected by the transmission output 200mW, the article ID 102c is not detected, the transmission output is further increased by 50mW and the transmission output is 250mW. The example of the identification information at the time of detecting goods ID102c in the interrogator 104h when the detection in 104a-104i is performed in order is shown.

  This is because the disposition of the interrogators 104a to 104i in FIG. 1A increases identification information focused on the detection result of the article 102c when the interrogation wave transmission output is increased (at the time of 100 mW transmission output of the interrogator 104i). Identification information at the time of 150 mW transmission output of the interrogator 104e, and identification information at the time of 250 mW transmission output of the interrogator 104h).

  The reason why the identification information is illustrated by paying attention to the detection result of the article 102c is to match the position estimation method of the article 102c with FIG. 8 described later based on FIG. 4A.

  The identification information of the interrogators 104a, 104b, and 104c when the transmission output of the interrogation wave is 50 mW is transmitted in order from the interrogator 104a with the same identification information in the identification information database 202. It was illustrated to show that the identification information obtained in this way is accumulated in order.

  In the identification information database 202, the identification information of the article tags 102a to 102c and the position tag 101 (x, y) detected while sequentially changing the transmission output setting value and the transmission interrogator 104 is recorded in each row in FIG. 4A. To do. Hereinafter, the information in each row in FIG. 4A is referred to as “sequential detection information”.

  The items to be recorded as the sequential detection information are information 400 of the transmission time of the interrogation wave from the interrogator 104, information of the interrogator 401 that transmitted the interrogation wave, information 402 of the transmission output of the interrogation wave at that time, and the detected article The identification information 403 of the tag 102 and the identification information 404 of the detected position tag 101 are used. The transmission time information 400 is acquired from the timer 207.

  The identification information 403 of the article tag 102 and the identification information 404 of the position tag 101 recorded in FIG. 4A are not all the identification information detected by the query wave transmission at the time, but the same question processed in step S309 and step S310. The difference between the sum of the detection results detected with a smaller output of the transmission output of the device 104 and the identification information at the time is recorded.

  The reason for accumulating the difference from the previous detection result as this identification information is as follows.

  The identification information of the article tag 102 and the position tag 101 that can be detected by transmission of a large interrogation wave having a transmission output from the same interrogator 104 includes the article tag 102 and the position tag 101 that were detected by a smaller transmission output, and In addition, since the transmission output is increased, the identification information of the article tag 102 and the position tag 101 that can be newly detected is added. For this reason, even if the difference between the identification information is accumulated in the sequential detection information as described above, by recording the detection time 400, the detector 401, and the transmission output 402, the same detector previously detected and recorded By obtaining the sum of the differences in the identification information detected by the interrogation wave having a smaller transmission output at, all the identification information detected at each detection time can be restored.

  Therefore, it is desirable to record the difference of identification information rather than to record all the redundant identification information detected by each transmission output and increase the necessary storage capacity in the identification information database 202.

  Next, information in the position specifying information database 204 will be described with reference to FIG. 4B.

  The position specifying information database 204 stores position information of the position tag 101 (x, y). For example, examples of position information of the position tag 101 (x, y) are the identification information 410 of the position tag 101, the X coordinate 411 and the Y coordinate 412 in the article position management environment 100.

  Further, in the position specifying information database 204, the interrogator 104 capable of detecting each position tag 101 in each interrogator 104 in the search environment 100 as a relationship between each position tag 101 and each interrogator 104 at a fixed position. The information 413 can be stored.

  Regarding the accumulation of the information 413 of the interrogator 104 that can detect each position tag 101, the position tag state that can be detected by the maximum output of each interrogator 104 in the initial steady state of the radio wave environment in the article position management environment 100. It can be recorded. By storing information related to the position tag 101 in the position specifying information database 204 such as information 413 of the interrogator 104 that can detect each position tag 101, the information from each interrogator 104 to each position tag 101 is stored. It is also possible to evaluate fluctuations in the radio wave arrival environment.

  Next, an outline of the basic operation of the article position estimation process in the embodiment of the present invention will be described with reference to FIG.

  In the description using FIG. 8, the position tag 101 in the vicinity of the article tag 102 is followed while following an example of accumulation of identification information in the identification information database 204 in order to facilitate detailed understanding of the article position estimation processing flow described later. A specific example of a method of using the identification information history of the article tag 102 and the position tag 101 for identifying the item tag will be described.

  FIG. 8 is a diagram in which an auxiliary frame for indicating an outline of the basic operation of the article position estimation process and its reference are added based on FIG. 4A described above (a specific example of the identification information database 204).

  Specifically, the position tag 101 (9, 2) in the vicinity of the article tag 102c when the interrogator 104h detects the article tag 102c at the transmission output at time 11:30:20 is sequentially stored in the identification information database 204. A procedure for identifying detection information retrospectively will be described.

  In FIG. 8, when the interrogator 104h detects the article tag 102c at the transmission output of a 250 mW interrogation wave at time 11:30:20 (see reference numeral 801), the article position estimation means 203 determines the position of the article tag 102c. Perform processing to identify. In the article position estimation, first, the history of sequential detection information in which the article tag 102c is detected is extracted while retroactively checking the history of sequential detection information in the identification information database 204. In FIG. 8, sequential detection information 806 including the history of the article tag 102c (see reference numeral 802) detected by the interrogator 104e at a transmission output of 150 mW at time 11:28:56, and time 11:26:30. Sequential detection information (see reference numeral 807) including the history of the article tag 102c (see reference numeral 803) detected by the interrogator 104i with a transmission output of 100 mW is extracted. At this time, in the sequential detection information 805, the position tag detected at the same time as the article tag 102c (see reference numeral 801) is 101 (7, 3) [the position tag written as (07, 03) in FIG. 8]. means. The same applies to the following. ], 101 (4,1), 101 (9,2), 101 (5,3), etc., and the position tag detected simultaneously with the article tag 102c (see reference numeral 802) in the sequential detection information 806 is 101 (6, 3), 101 (5, 5), 101 (7, 2), 101 (9, 2), etc., and detected in the sequential detection information 807 at the same time as the article tag 102c (see reference numeral 803). The position tags are 101 (12, 2), 101 (9, 2), 101 (10, 3), 101 (11, 3) and others.

  FIG. 7A is a schematic diagram in real space showing the detection status of the article tag 102c based on the three sequential detection information (see reference numerals 805, 806, and 807). In FIG. 7A, the article tag 102 or the position tag is obtained by the three interrogators 104e, 104h, 104i when the transmission output of each of the interrogators 104e, 104h, 104i in the article position management environment 100 is 150 mW, 250 mW, 100 mW. The ranges that can be detected by 101 are shown inside closed curves indicated by broken lines 701a, 703a, and 705a, respectively. In addition, when the transmission output of each interrogator 104e, 104h, 104i is one step lower, 100 mW, 200 mW, 50 mW, the ranges detectable by each interrogator 104e, 104h, 104i are indicated by broken lines 701a, 703a, 706a, respectively. Shown inside closed curve. At this time, the position tag 101 (x, y) detected by the identification information 801 including the detection of the article 102c in the identification information database 204 in FIG. 4A is arranged in an area sandwiched between the closed curves 703a and 704a. The position tag 101 (x, y) that is detected by the identification information 802 is the position tag 101 (x, y) that is disposed in the area between the closed curves 701a and 702a. y), and the position tag 101 (x, y) detected by the identification information 803 is the position tag 101 (x, y) arranged in the region sandwiched between the closed curves 705a and 706a. The reason for the information sandwiched between the two closed curves is that the identification information stored in the identification information database 204 as described above is the difference information of the detectable identification information that has changed according to the increment of the transmission output of the interrogator 104. It depends.

  In the situation shown in FIG. 7A, the article tag 102c is detected by three interrogators 104e, 104h, and 104i (a region sandwiched between closed curves 703a and 704a, a region sandwiched between closed curves 701a and 702a, and a closed curve 705a and 706a). The position tag 101 (9, 2) in the common area of the sandwiched area) is naturally also in the common area of the detection range of the three interrogators 104e, 104h, 104i. Therefore, in order to specify that the position tag 101 (x, y) in the vicinity of the article tag 102 is the position tag 101 (9, 2), identification of the articles 801, 802, and 802 in FIG. 4A is performed. Position tag 101 (9, 2) common among position tags 101 (x, y) included in sequential detection information including information (see reference numerals 805, 806, and 807) (see reference numeral 804 in FIG. 4) ). The position information of the specified position tag position tag 101 (x, y) is stored in the position specifying information database 204, and the position tag position tag 101 (9, 2) located in the vicinity of the specified article tag 102c. ) Is used as the position information of the article tag 102c.

  Next, the article position estimation processing flow of the article position estimation means 203 for realizing the article estimation will be described with reference to FIG.

  The article position estimation process starts by starting the computer 105 and starting the article search system.

  When the article search system is activated, the article position estimation unit 203 starts and starts until the identification information of the article tag 102 is found in the sequentially detected information by the latest query wave transmission in the read identification information database 202 (step S501). The process of sequentially reading the latest sequential detection information in the identification information database 202 (step S500) is repeated until there is an end command from the operator (Yes in step S506).

  In step S501, the article position estimation unit 203 finds the identification information of the article tag (any of the article tags 102a to 102c in FIG. 1A: hereinafter referred to as a detected article tag) in the latest sequential detection information. The article position specifying process (article search process) (step S502), which will be described later, operates, and the article position estimating process of the detected article tag 102 by the article position estimating unit 203 is performed.

  Next, in step S503, when the identification information of the plurality of detected article tags 102 exists in the sequential detection information found in step S501, the article position estimation unit 203 all of the identification information of the plurality of detected article tags 102. On the other hand, in order to sequentially execute step S502, the detected article tag 102 to be subjected to the article position specifying process in step S502 is sequentially changed (step S503). In step S503, if it is necessary to change the detected article tag 102 to the next of the detected article tags 102 sequentially detected in step S501 in the change of the detected article tag 102. Information that the sequential change to the plurality of detected article tags 102 discovered in S501 is completed is notified to Step S504.

  Next, in step S504, step S502 and step S503 are performed for all of the detected article tags 102 detected in step S501 by notification of information that the sequential change to the detected article tag 102 from step S503 is completed. When it is confirmed that the above process is performed (when step S504 is Yes), the process returns to step S500 as long as there is no termination command from the operator (as long as step S506 is No). On the other hand, when there is no notification of information indicating that the sequential change to the detected article tag 102 from step S503 has ended, that is, identification information of the detected article tag 102 that has not undergone the processing of step S502 and step S503 remains. (When step S504 is No), the processing from step S502 to step S503 is repeated by the article position estimation unit 203.

  If it is detected at step S506 that an operator's end command has been input (step S506 is Yes), the process ends.

  Next, the process flow of the article position specifying process (step S502) in the operation flow will be described with reference to FIG. 6A.

  In the detection step 600 of the detected article tag 102, the detected article tag (hereinafter, detected article tag 102t (specifically, illustrated) that is the target of the position tag specifying process in the vicinity of the article is determined from the information in the identification information database 202. However, for the sake of explanation, it is added for easy understanding.) The previous sequential detection information including the identification information is searched by the article position estimation means 203. At this time, the search range of the identification information of the detected article tag 102t in the identification information database 202 in step S600 does not need to be traced back beyond the sequential detection information that goes around the transmission output setting and the interrogators 104a to 104i. In addition, the interrogator 104 may be sequentially selected from the sequential search information of all the interrogators 104a to 104i and searched by the article position estimation means 203. Details of the search for the sequential detection information having the identification information of the detected article tag 102t will be described later.

  If a plurality of pieces of sequential detection information having identification information of the detected article tag 102t can be extracted as a result of the search in step S600 (No in step S601), the process proceeds to step S603.

  In step S603, a common position tag (hereinafter referred to as a common position tag 101com (specifically, among the plurality of sequential detection information retrieved and extracted in step S600) and the latest sequential detection information read in step S500 is described. Although not shown in the drawing, the identification information (hereinafter referred to as common position tag identification information) is specified by the article position estimation means 203.

  Next, in step S607, it is determined whether or not the common position tag 101com can be specified by the article position estimation unit 203 in step S603 or step S602 described later, and if it cannot be specified (Yes in step S607), It is determined that the article position cannot be specified, and the article position specifying process (step S502) is terminated. The fact that the common position tag 101com could not be found indicates that the article was moved during or near the time of movement.

  If the common position tag 101com can be specified in step S607 (No in step S607), the article position estimation unit 203 evaluates whether the identification information of the common position tag 101com is appropriate in step S604. To do.

  Whether the common position tag identification information is appropriate is evaluated as follows.

  In step S604, it is evaluated that one common position tag identification information is appropriate. In step S604, if there are a plurality of common position tag identification information, the position information of each common position tag 101com is read from the position specifying information database 204 by the article position estimation means 203, and the plurality of common position tags 101com are mutually connected. If the adjacent position tags 101 are adjacent to each other, it is determined to be appropriate, and if a plurality of common position tags 101com are separated from each other, it is determined to be inappropriate.

  If it is determined that the plurality of common position tags 101com are appropriate (Yes in step S605), the position of the article is calculated using the position information of the position tag 101com read from the position specifying information database 204 in step S606. .

  In step S606, when there is one common position tag 101com, the position information of the position tag 101com read from the position specifying information database 204 is set as the position of the article. When there are a plurality of common position tags 101com, the article position estimating means 203 may calculate the position of the center of gravity of the position information of the plurality of common position tags 101com as the article position. If the article position presentation to the operator by the article search system is not necessarily point position information such as the position of the center of gravity, an area where a plurality of common position tags 101com are present may be used as the article position. good.

  The article position calculated by the article position estimating means 203 is accumulated in the article position information database 205 by the article position estimating means 203, and the article position estimating process is terminated (step S607).

  When it is determined that the plurality of common position tags 101com are inappropriate (when Step S605 is No), the positions of the plurality of common position tags 101com are separated, and such a situation may occur. However, it is possible to assume that a very unique situation occurs, such as the appearance of a local detection spot due to the reflection of radio waves or the interference of radio waves induced by the radio waves. In such a case, it is determined that the article position cannot be specified, and the process ends. In this case (when step S605 is No), it is possible to notify the operator that a radio wave environment abnormality has occurred.

  In addition, when a plurality of pieces of sequential detection information having the identification information of the detected article tag 102t cannot be extracted in the search result in step S600 (Yes in step S601), the interrogator detection range is originally set. It can be seen that any of the interrogators 104 having a detection range in which the article tag 102 can be detected in the initial setting falls into a state where detection is not possible (detection abnormality). In this case, the detection abnormality process in step S602 is performed.

  In the detection abnormality process (step S602), any of the interrogators 104a to 104i that specify the detected article tag 102t (hereinafter, 104x (specifically not shown, but understood for explanation)). In the vicinity of the interrogator (hereinafter referred to as interrogator 104xa (which is not specifically shown, but is added for ease of understanding in the description)). )) When the detected article tag 102t that should be detected cannot be detected (Yes in step S601). In this case, the fact that the detected article tag 102t cannot be detected means that a position tag (hereinafter referred to as a position tag 101t (which is not specifically shown, but not illustrated) is easy to understand. It can be assumed that it cannot be detected. If this assumption is interpreted paradoxically, in the interrogator 104xa adjacent to the interrogator 104x that identifies the detected article tag 102t, the undetectable position tag 101t may be in the vicinity of the detected article tag 102t. It can be said that the position tag 101t has a characteristic.

  A position tag that cannot be detected by the interrogator 104xa adjacent to the interrogator 104x that identifies the article tag 102t to be detected (hereinafter referred to as a position tag 101t (specifically not shown, but for the sake of easy understanding) The interrogator 104xa obtained from the information 413 (see FIG. 4B) of the interrogator 104 capable of detecting the position tag 101 in the position specifying information database 204 shown in FIG. 2A is in the initial setting stage. The position tag 101xa that can be detected and the position tag that can be detected by the interrogator 104xa at the time of step S601 (hereinafter referred to as the interrogator 104xb (specifically, not shown, but are attached for easy understanding). It can be specified by obtaining the difference of. The identification information of the position tag 101t that cannot be detected by the interrogator 104xa adjacent to the interrogator 104x and the identification information in the sequential detection information including the detected article tag 102t that identifies the detected article tag 102t in step S502. If a common position tag 101com is specified among the position tag information, a common position tag 101com having the same meaning as the common position tag 101com obtained among the plurality of sequential detection information obtained in step S603 can be found. I can do it.

  The operation flow of the detection abnormality process (step S602) described above will be described with reference to FIG. 6B.

  In step S611, an interrogator adjacent to the interrogator 104 that has detected the sequential detection information read in step S500 (adjacent positions having overlapping detection ranges such as 104h and 104d described in FIG. 1B with the maximum transmission output). Refers to the interrogator 104.) 104 is identified.

  In step S612, the identification information of the position tag 101xa that can be detected by each adjacent interrogator 104xa is extracted from the information of the interrogator 104 that can detect the position tag 101 in the position specifying information database 204.

  In step S613, the identification information 404 of the position tag 101xb in a state that can be detected by each adjacent interrogator 104xa is extracted by retroactively searching the identification information 404 of the position tag 101 in the sequential detection information in the identification information database 202. To do.

  In step S614, the identification information of the position tag 101xa that can be detected by each adjacent interrogator 104xa extracted in step S612 and the position tag 101xb that is in a detectable state extracted by each adjacent interrogator 104xa extracted in step S613. Information is compared and the position tag 101t in the state which cannot be detected in the adjacent interrogator 104xa is specified.

  In step S615, between the identification information of the position tag 101t that cannot be detected by the adjacent interrogator 104xa specified in step S614 and the identification information 404 of the position tag 101 in the sequential identification information read in step S500. The identification information of the common position tag 101com is selected and extracted as the identification information of the common position tag 101com.

  By extracting the identification information of the common position tag 101com, the detection abnormality process (step S602) ends, and the process returns to step S604.

  The detected article tag 102t is extracted from the sequential detection information accumulated in the identification information database 202 by the article position estimating means 203 described with reference to FIGS. 5, 6A, and 6B, and the article tag 102t It is possible to determine the common position tag 101com in the vicinity and specify the position information of the article tag 102t from the position information of the common position tag 101com.

  In the detection abnormality process (step S602), when the common position tag 101com is found, the identification information of the position tag 101t that cannot be detected is extracted from the specific interrogator 104x (step S614). By accumulating in the database 205, it is possible to provide useful information when an article position is requested by an operation from the operation terminal 206. Details of this will be described in the description of processing in the operation terminal 206 described later.

  If the common position tag 101com cannot be found by the above procedure in step S602, the article tag 102t can be detected only by the interrogator 104x that identifies the detected article tag 102t, for example, the position tag 101 in FIG. 1A. The interrogator 104 is out of the arrangement of (1, 8) and exists in the detectable range of only the interrogator 104a.

  Originally, if the maximum transmission output of the interrogator 104 and the arrangement of the interrogator 104 can be detected in a plurality of directions, an area that can be detected only by the specific interrogator 104 as described above is considered. Although there is no need to do this, there is only one range that can be detected only by the specific interrogator 104, and when looking at the accuracy of specifying the range of the article position, 101 (1, 8) in FIG. Even if the area of the position tag 101 exists, the position information of the position tag 101 within the detectable range of only the interrogator 104a among the position tags 101 existing in the sequential detection information specifying the detected article tag 102 is described below. Thus, the item position information can be obtained. In such a case, information on the position tag 101 that can be detected only by the specific interrogator 104 may be returned to S602 as the common position tag in step S615.

(Retrieval of sequential detection information having identification information of detected article tags)
Next, in the description of the search range of the identification information of the detected article tag 102t in the identification information database 202 in step S600 described above, the search range of the identification information of the detected article tag 102t in the identification information database 202 in step S600. Does not need to be traced beyond the transmission output setting and the detection result of one round of the interrogator 104, and if the interrogator 104 is selected and searched from the sequential search information of all the interrogators 104a to 104i. A supplementary explanation of the reason will be given for the part that was described as good.

  In the first embodiment, as illustrated in FIG. 1B, adjustment is performed so that detection ranges from a plurality of directions can be detected at the time when the transmission output of the interrogation wave from each interrogator 104 is maximum. With this setting, all the article tags 102 and position tags 101 in the article position management environment 100 are set in different three-way interrogators 104 in one transmission output setting controlled by the interrogator control means 201 and one round of the interrogator 104. It is possible to detect duplicates within the detection range. That is, when searching for the identification information of the detected article tag 102 by going back to the sequential detection information in the identification information database 202, there is no need to search retrospectively for past sequential detection information of one or more rounds.

  Next, in order to show a specific example of the flowchart operation of the article position estimating means 203, an overview of the basic operation of article position estimation is shown in an overhead view of the article position management environment 100 (FIGS. 7A and 7B) and in the identification information database 202. The common position tag specifying processing operation will be described with reference to FIG.

  7A and 7B are diagrams showing radio wave environments when the article tag 102c is detected by the three interrogators 104e, 104h, and 104i on the overall system configuration diagram of FIG. 1A.

  FIG. 7A shows a general home environment in which propagation of radio waves is hindered by a floor plan structure or furniture, etc., in which the first embodiment is an article position sensing environment, and FIG. 7B is transmitted from the interrogator 104. It shows an ideal environment where there is no factor that hinders interrogation.

  Unlike the concentric circles 701b, 702b, 703b, 704b, 705b, and 706b showing the position tag detection ranges with the same radio wave intensity in the ideal radio wave environment shown in FIG. 7B, closed curves 701a and 702a showing the detection ranges with the same radio wave intensity shown in FIG. 7A. , 703a, 704a, 705a, and 706a are deformed by the passage of the structural wall or the partition wall, and generally the radio wave reach after the passage of the structural material is reduced.

  The closed curve 701a and the concentric circle 701b indicate the positions of the interrogation waves transmitted by the interrogator 104e when the interrogator 104e acquires sequential identification information including the identification information detected by the interrogator 104e in the environments shown in FIGS. 7A and 7B. The range in which the tag 101 or the article tag 102 can be detected is shown. Similarly, the closed curve 702a and the concentric circle 702b are obtained when the interrogator 104e acquires the previous sequential identification information for detecting the article tag 102c in each environment. This indicates the range in which the interrogation wave can be detected.

  At this time, the tag identification information accumulated in the identification information database 202 as a result of the interrogator 104e transmitting the interrogated wave of the closed curve 701a and the concentric circle 701b is the interrogated wave output of the closed curve 701a and the closed curve 702a, and the concentric circle 701b and the concentric circle 702b. The difference between the position tag 101 and the article tag 102 that can be detected is the position tag 101 and the article tag 102 in the donut region between the closed curve 701a and the concentric circle 701b and the closed curve 702a and the concentric circle 702b.

  7A and 7B, the interrogator 104h and the interrogator 104i are similarly illustrated.

  In the ideal radio wave environment shown in FIG. 7B, from any interrogator 104, from the interrogator 104 to the position tag 101 and the item tag 102 indicated by the identification information stored in the identification information database 202 in the transmission output of each interrogation wave. Can be calculated from the transmission output of the interrogation wave. This distance calculation can be realized by measuring in advance the transmission output of the interrogation wave and the distance between the position tag 101 or the article tag 102 that can be detected at the time of the transmission output. In this case, a plurality of questions can be obtained from the transmission output of each interrogation wave when the plurality of interrogators 104 detect the article tag as in Conventional Example 3, without arranging the position tag 101 as in the first embodiment. The distance from the instrument 104 to the article tag can be calculated, and the article position can be specified by a triangulation method.

  On the other hand, in FIG. 7A showing the article position management environment 100 as a target of the first embodiment, the identification information formed between the closed curve 701a and the closed curve 702a, the closed curve 703a and the closed curve 704a, and the closed curve 705a and the closed curve 706a. Therefore, the distance between the interrogation wave transmission output and the position tag 101 or the article tag 102 that can be detected at the time of the transmission output is not constant. The distance to the tag cannot be calculated. However, according to the article search system shown in the first embodiment, no matter how the radio wave region is deformed, as long as the article tag 102c can be detected, the position tag 101 existing in the vicinity can be detected. It is. At this time, for example, if there are position tags 101 (6, 4) and 101 (9, 2) detected by two interrogators (104e, 104h) simultaneously with the article 102c as shown in FIG. The position tag 101 (9, 2) that can be commonly detected by the devices (104e, 104h, 104i) can also be specified. In the first embodiment, since the three interrogators (104e, 104h, 104i) can detect in common, the position of the article tag 102 is between the closed curve 701a and the closed curve 702a, and between the closed curve 703a and the closed curve 704a. And the position tag 101 (9, 9) detected by the three interrogators in common with the article tag 102c can be specified as a region of identification information formed between the closed curve 705a and the closed curve 706a. 2) can be specified as the position having the highest degree of commonality.

  Next, an example of stored information in the article position information database 205 will be described with reference to FIG.

  In the article position information database 205, the position information of the detected article tag 102 identified in step S606 is the identification information 900 of the detected article tag 102, the X coordinate value 901, the Y coordinate value 902 in the article position management environment 100, Accumulate as. When the position information of the specific article tag 102 is updated in step S606, the position information is updated by the article position estimation means 203.

  It is also useful to add the identification information 903 of the position tag 101 that is in the undetectable state near the article. This information can be acquired during the detection abnormality process in step S602.

  Also, individual attribute information (article name, shape, material, color, etc.) 904 for each article can also be stored in accordance with the article identification information 900.

  Next, a processing flow of display processing of article position information on the operation terminal 206 will be described with reference to FIG.

  The operation terminal 206 starts by starting the computer 105 and starting the article search system. The operation terminal 206 forms a repetitive process of waiting for an article position inquiry from the operator in step S1000. Inside the repetitive processing, the update of the article position in the article position information database 205 is detected by the database access means 208 (step S1001). When the update of the article position is detected, the database access means 208 and the operation terminal 206 are operated. The information is displayed on the display 206b attached to the terminal 206 (step S1002).

  In step S1000, an article position inquiry from the operator detected by the operation terminal 206 is made by inputting identification information of the article from an operation I / F such as a keyboard 206c attached to the operation terminal 206 or a microphone 206d.

  When an inquiry about the article position is detected by the operation terminal 206 in step S1000, the position information of the article recorded in the article position information database 205 is read by the database access means 208 based on the identification information of the inquired article (step S1000). In step S1003, the database access unit 208 and the operation terminal 206 clearly indicate the article position displayed on the display 206b attached to the operation terminal 206 from the position information of other articles in step S1002 (step S1004). ).

  At this time, when the identification information 903 of the position tag 101 that is in the undetectable state in the vicinity of the article is attached to the article information (when step S1005 is Yes), the position tag 101 in the undetectable state is clearly indicated. In addition, the information of the identification information 903 of the position tag 101 can be transmitted, and the removal or removal of the radio wave environment factor that makes the position tag 101 undetectable can be instructed or displayed (step S1006).

  A specific example of the article position inquiry process at the operation terminal 206 in FIG. 10 will be described mainly with reference to FIGS.

  If the information in the article position information database 205 is in the state shown in FIG. 9, the article position management environment 100 is displayed on the display 206d attached to the operation terminal 206 as shown in FIG. .

  In the article position information display process in step S1002 of FIG. 10, the article position information in FIG. 9 is displayed as indicated by reference numerals 1100, 1101, and 1102. At this time, as the display form, the identification information “102a” may be displayed as it is as indicated by reference numeral 1100, or may be indicated by the article name “wallet” as indicated by reference numeral 1001 (the article 102b indicates “ In the case of “wallet”), graphic information may be displayed using shape information obtained from the article attribute 904 as indicated by reference numeral 1102. By displaying in this way, the operator can grasp the article position directly from the display on the display 206d without inputting an inquiry from the operation terminal 206. When it is difficult to find the position of the article directly from the display 206d, the operator uses the operation terminal 206 to obtain the identification information of the article from the operation interface such as the keyboard 206c attached to the operation terminal 206 or the microphone 206d. To the database access means 208. In this case, in the display of the article position in step S1004, in order to show the article position information obtained in step S1003, an arrow 1103 is displayed on the display 206d, or the article display of reference numerals 1100, 1101, and 1102 is blinked. The position of the article is clearly indicated by coloring or coloring.

  Further, since the position tag identification information 903 in the undetectable state near the article is attached to the position information of the article tag 102c in FIG. 9, the position of the undetectable position tag 101 is denoted by reference numerals 1103 and 1104. By clearly displaying the frame as shown and informing the operator that there is a radio interference near the position tag 101, the operator can move nearby articles (shelves, objects) that are likely to cause radio interference. Removal can be prompted (step S1006). Information on the position tag 101 in the undetectable state at this time can be acquired from the position specifying information database 204 by the database access means 208.

  In the description of the first embodiment, the interrogation wave from the interrogator 104 has been described as an example in which the interrogation wave is radiated in the form of a closed curve centering on the interrogator 104. In the article search system according to the first embodiment, there is no restriction on the transmission shape of the interrogation wave from the interrogator 104, and it is possible to detect that the inside of the article position management environment 100 overlaps due to the transmission of interrogation waves from multiple directions. If it is good. Therefore, even if the interrogation wave from the interrogator 104 has directivity, if the interrogator 104 can be arranged so as to overlap the article position management environment 100 in one cycle of the interrogation wave transmission procedure, The technology of the article search system according to the first embodiment can be used.

  In the description of the first embodiment, the position tag 101 (x, y) is described in a two-dimensional manner. However, the position tag 101 can be placed at a position where an article can be placed (for example, a ceiling, a floor surface, By arranging the interrogator 104 in a three-dimensional manner on a three-dimensional space on the side of equipment such as walls and shelves, etc., and arranging the interrogator 104 so that the detection areas of a plurality of interrogation waves overlap, You can explore.

  In the description of the first embodiment, the position tags 101 (x, y) are arranged in order on the X and Y coordinate axes in the article position management environment 100. However, the article search system according to the first embodiment of the present invention. When the position information of the position tag 101 (x, y) is recorded in the position specifying information database 204, it may be arranged randomly or even three-dimensionally. The position tag 101 near the article tag 102 can be specified, and the article position can be estimated from the position information of the position tag 101. The points to be noted regarding the arrangement of the position tag 101 are the accuracy of the article position to be searched and the arrangement interval of the position tag 101. The position tags 101 may be densely arranged in the area where the accuracy of the article position is high, and the position tags 101 may be sparsely arranged in the area where the position accuracy is low.

  Regarding the accuracy of the article position to be detected, not only the arrangement of the position tag 101 but also the amount of change in the transmission output of the interrogation wave from the interrogator 104 is related. In the article search system according to the first exemplary embodiment of the present invention, improvement in the accuracy of the article position can be achieved by reducing the common detection area of the position tag from a plurality of directions. Since this common detection area is determined by the overlapping state from a plurality of directions of the area that can be detected as a difference from the detection area immediately preceding the area that can be detected when the transmission output of the interrogation wave changes, transmission of the interrogation wave The accuracy of the article position to be searched is controlled by adjusting the change amount of the output set value. However, in order to achieve high position accuracy, the amount of change in the query wave transmission output set value cannot be made as small as possible. The reason for this is that, in practice in the current state of RFID technology, simultaneous transmission of interrogation waves from neighboring interrogators 104 causes interference of interrogation waves and makes position tag detection unstable. Therefore, the transmission from each interrogator 104 needs to be performed by switching the output to time division, or in the transmission of each interrogation wave, the processing time for anti-collision processing for simultaneous detection of multiple tags For example, it is necessary to subdivide the amount of change in the transmission output of the interrogation wave, which increases the time required to go through the detection area in the article position management environment 100 with the interrogation wave of each interrogator 104. By letting you. In the description of the first embodiment, the amount of change in the query wave transmission output set value has been described as a predetermined amount. However, in actual implementation, the amount of change is small in a region where the required accuracy of the article position to be searched is high. In a region where the required accuracy of the article position to be searched is low, it can be adjusted by increasing the amount of change, and it is desirable to realize transmission of a query wave suitable for the article search system to be implemented.

  If the first embodiment is expanded as follows, it is possible to calculate a more detailed article position than the center of gravity position of the common position tag 101com. For that purpose, the amount of change in the transmission output setting of the interrogation wave is made more detailed, and an operation flow for performing the detection operation again for the area around the estimated position of the article obtained as the center of gravity position is added, and the article tag 102 This can be realized by subdividing the positional relationship of the position tag 101 at the transmission output setting stage of the interrogator 104. Specifically, for example, the transmission output setting in increments of 50 mW shown in FIG. 4A is changed to increments of 5 mW, and the area around the estimated position of the article obtained as the center of gravity position is again If the common position tag 101com is detected, the sequential detection information of the detected article tag 102 and the common position tag 101com can be stored separately. For example, two common position tags 101com are detected at the first time and the eighth time in 10 sequential detection information detected again in increments of 5mW between transmission outputs in increments of 50mW. When 102 is present in the second sequential detection information, the article tag 102 is in a position where the two common position tags 101com are internally divided by 1: 6 in the direction component connecting the two common position tags 101com. Can be estimated. By interpolating and estimating the position of the detected article tag 102 based on the internal division relationship between the common position tag 101com and the detected article tag 102 that can be obtained in this way, Calculation is possible.

(Embodiment 2)
FIG. 12 shows a system configuration example of the second embodiment in which the article search system according to the second embodiment of the present invention is applied to an article location management environment 100 such as a home or office.

  The difference from the first embodiment (FIG. 1A) is the mounting form of the interrogator 104.

  In the second embodiment, the interrogators 104v and 104w are mounted on mobile robots 106a and 106b that move within the article position management environment 100 (in FIG. 12, for example, two-wheeled mobile robots).

  The position tag 101 (x, y) and the article tags 102a to 102c are the same as those in the first embodiment.

  The mobile robots 106a and 106b output interrogation waves of constant intensity from the interrogators 104v and 104w mounted on the mobile robots 106a and 106b, respectively, and position tags 101 and 120 in the detection ranges 1200 and 1201 indicated by circles in FIG. While detecting the article tag 102, the floor in the article position management environment 100 is moved.

  As an example, the computer 105 arranged in the article position management environment 100 acquires the identification information of the position tag 101 and the article tag 102 detected by the interrogators 104v and 104w by wireless communication mounted on the mobile robots 106a and 106b.

  FIG. 13A shows a processing configuration in the computer 105 operating in the system configuration and a connection state as an article search system.

  The difference from Embodiment 1 (FIG. 2A) is that the computer 105 is connected to all the interrogators 104v to 104w by wireless communication, and all the interrogators control means 201 functions as an example of the interrogator control means 201. This is a point for controlling the interrogators 104v to 104w.

  Each mobile robot 106a, 106b must be equipped with wireless communication means 1307, 1308.

  Other constituent means (identification information database 1302, article position estimation means 1303, position specifying information database 1304 as an example of a search information database, article position information database 1305, database access means 1309, operation terminal 1306) are shown in FIG. 13A. Within the scope of the description, the identification information database 202, the article position estimation means 203, the position specification information database 204, the article position information database 205, the database access means 208, and the operation terminal 206 in FIG. Perform a role.

  FIG. 13B shows a configuration example of the mobile robot 106a as a representative example of the mobile robots 106a and 106b. The movement control means 1310 is connected with a communication means 1307, a movement device 1311, and a route generation means 1312. The communication unit 1307 is connected to the interrogator 104v. The mobile robot 106b has the same configuration and function as the mobile robot 106a. The mobile robot 106a transmits a movement control command generated by the movement control means 1310 to the moving device 1311 (for example, a wheel or a leg drive motor (motor for driving forward / reverse rotation of the wheel)). To move. The movement control command is generated so as to move on the movement path in the article position management environment 100 generated by the path generation unit 1312. During this movement, the movement control means 1310 identifies successive self-positions while updating the self-position (x, y) according to the command issued by itself. This self-location information is transmitted to the communication means 1307.

  The communication unit 1307 transmits an interrogation wave transmission command to the interrogator 104v, and wirelessly transmits information on the article tag 102 and the position tag 101 detected by the interrogation wave to the interrogator of the computer 105. It transmits to the control means 1301. Details of the operation flow of the communication unit 1307 will be described later with reference to FIG.

  Differences from the first embodiment in carrying out the second embodiment in more detail will be described below.

  Unlike the first embodiment, in the second embodiment, the interrogators 104v and 104w are mounted on the mobile robots 106a and 106b. At this time, the interrogators 104v and 104w transmit interrogation waves according to the fixed movement distances of the robots 106a and 106b. At this time, since the movement operation of the robots 106a and 106b plays a role of the transmission output fluctuation of the interrogation wave of the interrogator 104 at the fixed position in the first embodiment, transmission of the interrogation wave from the interrogators 104v and 104w. The output may be fixed. A specific example is shown in FIG. Reference numerals 1400 and 1401 indicate detection ranges of the robots 106a and 106b that transmit the interrogation wave. After transmitting the interrogation wave in the detection range 1400, the robot 106a moves, and the interrogation range of the interrogation wave transmitted at the moved position is 1401. At this time, the information of the position tag 101 and the article tag 102 detected in the hatched area indicated by reference numeral 1402 is stored in the identification information database 1302. The identification information of the position tag 101 and the article tag 102 detected in the hatched area 1402 is the position tag 101 and article detected in the detection range 1400 from the identification information of the position tag 101 and article tag 102 detected in the detection range 1401. Selection can be made by removing the identification information of the tag 102.

  The identification information of the position tag 101 and the article tag 102 detected in the hatched area 1402 indicates that the position tag 101 and the article tag before and after the transmission output fluctuation of the interrogation wave of the fixed interrogator 104 in the first embodiment. It plays the same role as the difference between the detection results of 102.

  FIG. 15 shows a specific example of information stored in the identification information database 1302 when the interrogators 104v and 104w are mounted on the mobile robots 106a and 106b as in the second embodiment.

  In the identification information database 1302 in the second embodiment, the detection time information 1500 shown in FIG. 15, the type information 1501 of the mobile robots 106a and 106b, the x and y coordinate position information 1502 of the mobile robots 106a and 106b, Information comprising the identification information 1503 and 1504 of the article tag 102 and the position tag 101 that can be detected in the inquiry wave transmission at each detection time is stored.

  The x and y coordinate position information 1501 of the robots 106a and 106b at this time can be acquired by reading internal data that the mobile robots 106a and 106b generally hold in order to manage their own positions.

  Next, FIG. 16 shows an operation flow of the wireless communication unit 1307 (the wireless communication unit 1308 is the same processing flow as the wireless communication unit 1307) of the mobile robot 106a for sequentially storing the detection information in the identification information database 1302. Shown in

  The wireless communication means 1307 of the mobile robot 106a starts when the mobile robot 106a is activated. In step S1600, the current position of the mobile robot 106a itself is fixed by the movement control means 1310 as the starting position information of the movement distance evaluated in step S1602.

  In step S1601, the movement control means 1310 calculates the movement distance from the difference between the current value of the self-position that changes with the movement of the mobile robot 106a and the starting position information.

  Next, when the movement control means 1310 determines that the movement distance is a predetermined amount (when step S1602 is Yes), the interrogator 104v mounted on the mobile robot 106a is used to surround the mobile robot 106a. The position tag 101 and the article tag 102 are detected (step S1603).

  Next, in step S1604, the detected tag information is transmitted from the wireless communication means 1307 to the interrogator control means 1301 together with the identification information of the mobile robot 106a itself and the information on the self position. After the transmission is completed, the process returns to step S1600 as long as there is no termination command from the operator (No in step S1605).

  If the movement control unit 1310 determines that the movement distance is not a predetermined amount (when step S1602 is No), the process returns to step S1601.

  The above process ends when the operator's end command is input at step S1605 (when step S1605 is Yes).

  Next, FIG. 17 shows an operation flow of the interrogator control means 1301 for accumulating the detection information in the identification information database 1302 sequentially.

  In step S1700, the interrogator control unit 1301 repeats a loop process that waits for communication from the wireless communication unit 1307 of the mobile robot 106a. The interrogator control means 1301 receives the result of transmitting the identification information of the position tag 101, the identification information of the mobile robot 106a, and the position of the mobile robot 106a in step S1604 of the wireless communication means 1307 of the mobile robot 106a (step S1700). In the case of Yes), the received information is recorded in the identification information database 1302 (step S1701). In step S1700, if there is no transmission from the mobile robot 106a (when step S1700 is No), the transmission result from the mobile robot 106a is displayed as long as there is no end command from the operator (step S1702 is No). The loop of step S1700 is repeated until reception.

  In the loop in which step S1700 is repeated, when it is detected in step S1702 that an operator's end command has been input (step S1702 is Yes), the above process ends.

  Unlike the change in the transmission output of the interrogator 104 in the first embodiment, in the sequential detection by the mobile robot 106a, the identification information result obtained by each detection differs depending on the movement distance and direction. If the inclusion relationship does not hold and the successive detection results are regarded as the difference between the identification information, it becomes impossible to restore all the detection results every time as the sum of the past detection results.

  Therefore, the sequential detection information in the identification information database 1302 is not the hatched area 1402 in the above description using FIG. The identification information of the position tag 101 and the article tag 102 that can be newly detected within the range is recorded.

  Next, an operation flow of the article position estimation unit 1303 will be described with reference to FIG.

  The article position estimating means 1303 starts by starting the computer 105 and starting the article search system, as in the first embodiment.

  In step S1800, the latest sequential detection information in the identification information database 1302 is read by the article position estimation means 1303, and the presence / absence of the identification information of the article tag 102 in the identification information 1503 of the article tag 102 of the latest sequential detection information is determined. The position is estimated by the position estimation unit 1303 (step S1801).

  If the article position estimation means 1303 determines that the identification information (detected article tag) of the article tag 102 has been detected (if step S1801 is Yes), step S1802 of the article position specifying process is executed and detected. If there is not (when Step S1801 is No), the process returns to Step S1800 and reads the latest sequential detection information as long as there is no input of an end command from the operator (Step S1806 is No). Repeat with 1303. If it is detected in step S1806 that an end command has been input from the operator (if step S1806 is Yes), the above process ends.

  Next, in step S1802, the article position specified in step S1802 of the article position specifying process is stored in the article position information database 1305. The interior of step S1802 of the article position specifying process will be described later.

  Next, in step S1803, in order to perform step S1802 of the article position specifying process for all the identification information of the detected article tag 102 that has been confirmed to be detected in step S1801, confirmation is made in step S1801. If there is a plurality of identification information of the detected article tag 102, the identification information of the detected article tag 102 that is the target of step S1802 of the article position specifying process is changed to the identification information of the next detected article tag ( In step S1803), in step S1804, the article position estimation unit 1303 determines whether or not step S1802 of the article position specifying process has been completed for all the identification information of the detected article tag 102 confirmed in step S1801. If not completed (if step S1804 is No), the process returns to step S1802, and step S1802 of the article position specifying process is repeated.

  In step S1804, when step S1802 of the article position specifying process is completed for all the identification information of the detected article tag 102 confirmed in step S1801 (when step S1804 is Yes), the process returns to step S1800, and the identification information The process after reading the latest sequential detection information in the database 1302 is repeated.

  Next, the processing flow of step S1802 of the article position specifying process by the article position estimating unit 1303 will be described with reference to FIG.

  In step S19000, the article position estimation unit 1303 searches the information in the identification information database 1302 for previous sequential detection information having identification information of the detected article tag 102 that is the target of the position tag specifying process in the vicinity of the article. At this time, in the search range of the identification information of the detected article tag 102 in the identification information database 1302 in step S19000, it is necessary to set an upper limit that goes back in advance, for example, by time or the number of detection information sequentially. . This is different from the case where the detection ranges of the interrogators 104 are set so as to overlap each other in the initial setting as in the first embodiment, and the identification stored in the identification information database 1302 in the second embodiment. This is because the information is information detected at an unspecified position due to the movement of the mobile robot.

  Further, the information in the identification information database 1302 includes the identification information of the position tag 101 and the article tag 102 in the entire query wave detection range such as the detection range 1400 and the detection range 1401 in FIG. When searching for information including identification information of the article to be detected in the identification information database 1302, it is necessary to perform sequential detection information after changing it to detection information in the shaded area 1402.

  For this reason, in step S19000, first, the sequential detection information including the identification information of the detected article 102 identified in step S1801 is traced back in the time direction to the upper limit of the range in which the identification information database 1302 is searched in advance. Then, the article position estimation means 1303 searches and extracts from the identification information database 1302.

  Next, in step S19001, for each piece of sequential detection information that has been searched, the mobile robot that has detected each piece of sequential detection information uses the article position estimation unit 1303 to search for one piece of sequential search information that was previously detected.

  Further, in step S19002, from the identification information of the position tag that can be detected by each sequential detection information including the identification information of the detected article extracted above, the question of the same mobile robot before one of each sequential detection information. The identification information (hereinafter referred to as difference detection information) of the position tag from which the identification information of the position tag 101 in the sequential detection information detected by the device is deleted is generated. This difference detection information corresponds to the information of the position tag 101 that can be detected in the hatched area 1402 in FIG. 14 when each sequential detection information including the identification information of the detected article 102 is detected.

  Through the processing so far, the difference detection information having the shaded area 1402 in FIG. 14 including the detected article 102 identified in step S1801 can be extracted from the identification information database.

  When a plurality of pieces of difference detection information cannot be obtained by the processing from step S19000 to step S19002 (when step S1901 is Yes), the article position cannot be specified, and the article position specifying process is performed. Step S1802 ends.

  If a plurality of pieces of difference detection information can be obtained by the processing from step S19000 to step S19002 (step S1901 is No), the process proceeds to step S1902. In step S1902, the identification information (hereinafter referred to as the common position tag 101com) between the plurality of difference detection information generated in step S19002 and the difference detection information of the latest sequential detection information in the identification information database 1302 read in step S1800. , Common position tag information) is specified (extracted) by the article position estimation means 1303.

  Next, when the common position tag information cannot be specified by the article position estimation unit 1303 in Step S1903 (when Step S1903 is Yes), the position of the detected article cannot be specified, and the article position specifying process is performed. Step S1802 ends. If the common position tag information can be identified by the article position estimation unit 1303 in Step S1903 (when Step S1903 is No), the process proceeds to Step S1904.

  In step S1904, the article position estimation unit 1303 evaluates whether the identification information of the common position tag 101com is appropriate.

  Whether the common position tag identification information is appropriate (whether it is appropriate) is evaluated as follows.

  If there is one common position tag identification information, the position information is evaluated as appropriate. When there are a plurality of common position tag identification information, the position information of the common position tag 101com is read from the position specifying information database 204 by the article position estimation means 1303, and is appropriate when the common position tag 101com is an adjacent position tag 101. It is determined by the article position estimation means 1303 that there is. When the common position tag 101com is far away, the article position estimation unit 1303 determines that the common position tag 101com is inappropriate.

  When the article position estimating unit 1303 determines that the common position tag 101com is appropriate (when step S1905 is Yes), the article position estimating unit 1303 uses the barycentric position of the position information of the common position tag 101com as the article position in step S1906. Calculated by The calculated article position is accumulated in the article position information database 205 by the article position estimation unit 1303, and the article position estimation process is terminated. If the article position estimation unit 1303 determines that the common position tag 101com is not appropriate (No in step S1905), the article position is not calculated and the article position estimation process is terminated.

  Embodiment 2 in which the position tag 101 and the article tag 102 are detected by the interrogators 140v and 140w mounted on the mobile robots 160a and 160b by the processing of the article position estimation means 1303 using FIGS. In the article search system, the position of the article tag 102 can be specified.

  Unlike the case of the first embodiment, the article tag 102 whose position can be specified depends on the moving range and moving direction of the mobile robots 160a and 160b on which the interrogators 104v and 140w are mounted. The discovery of the position of the article tag 102 in the entire area of the article position management environment 100 is based on the premise of searching for the position of the article in the article search system in advance in the route of the mobile robots 160a and 160b in the second embodiment. It can be realized by planning in the route generation means 1312 so as to move all over the article position management environment 100. As a planning method, a predetermined route can be incorporated in the route generation means 1312 in advance.

  In addition, in order to apply the article position estimation method of the present invention described in the first embodiment and the second embodiment, a condition that the transmission / reception sensitivity of the article tag to be used and the position tag is equal is necessary. In order to make the explanation of the article position estimation method of the invention easier to understand, in the first embodiment and the second embodiment, the article tag to be used and the position tag are omnidirectional in the transmission / reception sensitivity of the interrogation wave. The explanation was based on the condition that The feasibility in the embodiments disclosed in the first embodiment and the second embodiment on the premise of using omnidirectional RFID is not impaired because omnidirectional RFID is also developed. Actually, use of an article tag and a position tag having directivity in transmission / reception sensitivity is also conceivable. In that case, by using an interrogator that can transmit interrogation waves based on circular polarization with no directivity, the difference in tag transmission / reception sensitivity due to the difference in the direction of the orientation of the tag and the position tag Regardless, it is possible to achieve uniform transmission / reception sensitivity with the article tag and the position tag regardless of the arrangement direction of the article tag and the position tag.

  If you want to use an article tag and a position tag with directivity and an interrogator that transmits an interrogation wave with linear polarization, the directivity of the transmission and reception sensitivity of the article tag and the position tag must be matched. A device to arrange the tag and the position tag in the same direction is required. In such a case, the article tag and the position tag are restricted to be perpendicular to the floor in the article location management environment 100 (eg, the position tag is embedded perpendicular to the floor and the article tag is By attaching the plane of polarization of the interrogation wave from the interrogator to the vertical direction, the arrangement direction of the article tag and the position tag is matched, and the horizontal plane is viewed from multiple directions. Can be sent and received.

  An article search system, an article search method, and an article search program according to the present invention can be used for a space article that cannot be expected to have a steady radio wave propagation environment simply by attaching a small passive RFID to an article that requires specification of a position. For example, it is useful for the purpose of searching for the position of an article moving in a general home or office where there are many structures such as partitions and shelves in a relatively narrow space.

Explanatory drawing which shows the whole structure of the article position specification system which concerns on Embodiment 1 of this invention. The figure which shows typically the state of the transmission wave of the interrogator 104h in the article location specification system which concerns on Embodiment 1 of this invention. The block diagram which showed the processing structure of each structure means programmed in the computer which concerns on Embodiment 1 of this invention. The block diagram which shows the structure of the interrogator of the article location specification system which concerns on Embodiment 1 of this invention. The block diagram which shows the structure of RFID common to the goods tag and position tag of the goods location specification system which concerns on Embodiment 1 of this invention. Process flow chart of interrogator control means according to Embodiment 1 of the present invention. Data configuration diagram in the identification information database according to the first embodiment of the present invention Data configuration diagram in position specifying information according to Embodiment 1 of the present invention Flowchart of article position estimation processing according to Embodiment 1 of the present invention Flowchart of article position specifying process according to Embodiment 1 of the present invention Process flowchart of step S602 of the abnormality detection process according to Embodiment 1 of the present invention. Explanatory drawing of the article position specifying method according to Embodiment 1 of the present invention Explanatory drawing of the article position specifying method according to Embodiment 1 of the present invention in an ideal radio wave environment Explanatory drawing of the common position tag specific process in the identification information database which concerns on Embodiment 1 of this invention Data configuration diagram in the article position information database according to Embodiment 1 of the present invention Processing flowchart of operation terminal according to Embodiment 1 of the present invention FIG. 4 is a configuration diagram of the display screen of the article position and the like on the operation terminal according to the first embodiment of the present invention. The block diagram which shows the whole structure of the article location specification system which concerns on Embodiment 2 of this invention. The block diagram which showed the processing structure of each structure means programmed in the computer concerning Embodiment 2 of this invention Block diagram showing a configuration example of the mobile robot 106a according to the second embodiment of the present invention. Explanatory drawing of the identification information accumulate | stored in the range which can be detected with the movement of the mobile robot which concerns on Embodiment 2 of this invention, and the query wave from an interrogator, and an identification information database Data configuration diagram in the identification information database according to the second embodiment of the present invention Processing flowchart of wireless communication means in mobile robot according to embodiment 2 of the present invention. Process flow chart of interrogator control means according to embodiment 2 of the present invention. Processing flowchart of article position estimation means according to Embodiment 2 of the present invention Process flow chart of article position specifying process according to Embodiment 2 of the present invention System configuration diagram of Conventional Example 2

Explanation of symbols

99 ・ ・ ・ RFID
99-1 ... Antenna 99-2 ... Transmission signal generation means 99-3 ... Transmission voltage generation means 99-4 ... IC
100 ... Article position management environment 101 ... Position tag 102 ... Article tags 102a, 102b, 102c ... RFID attached to the article
104 ... interrogator 104-1 ... antenna 104-2 ... transmission radio wave control means 104-3 ... received signal processing means 104-4 ... external interfaces 104a to 104i ... article position management Interrogators 104v, 104w installed in the environment ... Interrogators 105 installed on the mobile robot 105 ... Computers 106a, 106b ... Mobile robots 201, 1301 ... Interrogator control means 202, 1302 ... identification Information database 203, 1303 ... Article position estimating means 204, 1305 ... Position specifying information database 205, 1304 ... Article position information database 206, 1306 ... Operation terminal 206a ... Speaker 206b ... Display 206c ... Keyboard 206d ... Microphone 207 ... Timer 208 1309 ... database access means 1307 and 1308 ... communication means 1310 ... movement control means 1311 ... mobile device 1312 ... path generation unit

Claims (6)

An article ID transmitter / receiver that is attached to the article and receives the interrogation wave and transmits the identification signal of the article as a response;
The interrogation wave is transmitted from a plurality of directions to the search transceiver that responds to the interrogation wave and returns its identification signal, the response transmission from the article ID transceiver and the search transceiver is received, and the article ID transmission / reception And at least one interrogator for obtaining identification information of the transmitter and the search transceiver;
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
An identification information database for storing identification information of the article ID transmitter / receiver and the search transmitter / receiver received by the interrogator;
From the history of identification information of the article ID transceiver and the search transceiver stored in the identification information database, a search transceiver having a common detection state is specified for the detection state of the article from a plurality of directions. Article position estimation means for reading position information corresponding to the identified identification information of the search transceiver from the search information database and estimating the position of the article based on the position information corresponding to the read identification information of the search transceiver When,
An article position database for storing information on the estimated article position;
An article search system comprising:   The article search system according to claim 1, further comprising an operation terminal that retrieves article position information from the article position database by inquiring about the position of the article. An article ID transmitter / receiver that is attached to the article and receives the interrogation wave and transmits the identification signal of the article as a response;
The interrogation wave is transmitted from a plurality of directions to the search transceiver that responds to the interrogation wave and returns its identification signal, the response transmission from the article ID transceiver and the search transceiver is received, and the article ID transmission / reception A plurality of interrogators arranged so as to overlap each other in the area for managing the position of the article,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
The interrogator control means receives the response signals from the article ID transceiver and the search transceiver while gradually increasing or decreasing the transmission output of the interrogation wave from each interrogator. An identification information database for storing identification information of the received article ID transceiver and search transceiver;
Identification of an article ID transmitter and a search transceiver that can be detected or cannot be detected according to a change in transmission output of the interrogation wave from identification information histories of the article ID transmitter and the search transceiver in the identification information database. Extract the information history, and identify the search transceiver that became detectable or undetectable at the same time or near the same time for the specific article ID transceiver that became detectable or undetectable from the extracted identification information history Of the specified search transmitter / receiver, the search transmitter / receiver that is commonly detected by a plurality of interrogators and that can narrow down the detectable range to one region from the overlapping degree of the common detection ranges of the plurality of interrogators. Article position estimating means whose position is the article position;
An article position database for storing information on the estimated article position;
An article search system comprising: An article ID transmitter / receiver that is attached to the article and receives the interrogation wave and transmits the identification signal of the article as a response;
The interrogation wave is transmitted from a plurality of directions to the search transceiver that responds to the interrogation wave and returns its identification signal, the response transmission from the article ID transceiver and the search transceiver is received, and the article ID transmission / reception A plurality of interrogators arranged so as to overlap each other in the area for managing the position of the article,
A search information database for storing location information of the search transceiver in association with identification information of the search transceiver;
In the article search system having
Interrogator control means for controlling the transmission output or transmission timing of the interrogation wave from the interrogator so as to divide the respondable areas of the article ID transceiver and the search transceiver with time change;
The transmission output of the interrogation wave from each interrogator is gradually changed by the interrogator control means while receiving response signals from the article ID transceiver and the search transceiver, and the obtained An identification information database for storing identification information of the article ID transceiver and the search transceiver;
Identification of an article ID transmitter and a search transceiver that can be detected or cannot be detected according to a change in transmission output of the interrogation wave from identification information histories of the article ID transmitter and the search transceiver in the identification information database. Extract the information history, and identify the search transceiver that became detectable or undetectable at the same time or near the same time for the specific article ID transceiver that became detectable or undetectable from the extracted identification information history Position information of a plurality of search transceivers that can be specified in common among the search transceivers specified by the plurality of interrogators, and the plurality of searches specified above with the specific article ID transmitter / receiver Interpolate and estimate the article position based on the positional relationship between the article ID transmitter / receiver, multiple search transmitter / receivers, and interrogator estimated from the difference in the detection time change of the transmitter / receiver. And an article position estimating means,
An article position database for storing information on the estimated article position;
An article search system comprising: The above-mentioned question from a plurality of directions to an article ID transmitter / receiver that is attached to an article and receives an interrogation wave and transmits an identification signal of the article as a response and a search transceiver that responds to the interrogation wave and returns its own identification signal In a region that transmits waves, receives response transmissions from the article ID transceiver and the search transceiver, obtains identification information of the article ID transceiver and the search transceiver, and manages the position of the article An interrogator mounted on the moving body,
While transmitting the interrogation wave having a constant intensity from the interrogator while the moving body is moving, receiving the response signal from the article ID transmitter / receiver and the search transceiver, the obtained article ID transmitter / receiver and the search transceiver An identification information database for storing identification information of
The identification information history of the article ID transmitter and the search transceiver that can be detected or cannot be detected according to the movement of the mobile body from the identification information history of the article ID transmitter and the search transceiver in the identification information database. From the extracted identification information history, a search transceiver that can be detected or cannot be detected at the same time or at a close time is specified for a specific article ID transmitter that can or cannot be detected. Among the specified search transceivers, a search transceiver that is commonly detected by a plurality of interrogators and that can narrow down the detectable range to one region from the overlapping degree of the common detection ranges of the plurality of interrogators. Article position estimating means whose position is the article position;
An article position database for storing information on the estimated article position;
An article search system comprising: On the computer,
Controlling the transmission output of the interrogation wave from the interrogator;
Identification of an article ID transmitter / receiver which is received by the interrogator and which is attached to the article and receives the interrogation wave and transmits the identification signal of the article as a response and a search transceiver which responds to the interrogation wave and returns its own identification signal Storing information in an identification information database;
A search transmitter / receiver having a common detection state is identified and specified with respect to the detection state of the article from a plurality of directions based on the identification information history of the article ID transmitter / receiver and the search transmitter / receiver accumulated in the identification information database. The position information corresponding to the identification information of the search transceiver is read from the search information database that stores the position information of the search transceiver in association with the identification information of the search transceiver, and corresponds to the read identification information of the search transceiver An article search program for executing the step of estimating an article position based on position information to be performed.

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