JP2005354137A - Work management system, and communication apparatus and tag for use in that system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a work management system including a communication apparatus capable of communicating with a radio tag surely. <P>SOLUTION: The work management system comprises an antenna drive section 20 arranged integrally with a radio tag 2 given to a work W, a visual sensor 11 for detecting the work, and an antenna 12 for communicating with the radio tag and altering at least one of the orientation and position of the antenna, and a communication apparatus 1 provided with a section 10 for controlling the antenna drive section to communicate with the radio tag based on image information from the visual sensor. Since the communication apparatus included in the system can overlap the communication range of the antenna and the imaging range of the visual sensor, it can communicate surely with the radio tag by controlling the antenna drive section based on the image information from the visual sensor. The communication apparatus can communicate surely with the radio tag even when the work moves. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a system for managing all objects (hereinafter referred to as workpieces) to be managed using a wireless tag. More specifically, the present invention relates to a work management system including a communication device that can reliably communicate with a wireless tag.

  In recent years, attention has been focused on a system for managing a wireless tag capable of writing desired information attached to a work. The work management system includes a wireless tag attached to a work and a communication device having a function of writing information or reading information by communicating with the wireless tag. Such a work management system is used, for example, in a distribution base where sorting work is performed while a large amount of work is conveyed by a conveyor.

  In order to communicate between the communication device and the wireless tag, it is an indispensable condition that the antenna on the wireless tag side and the antenna on the communication device side exist within an area where they can communicate with each other. However, there are many cases where the position of the wireless tag changes irregularly during the transfer of the workpiece. If the position of the wireless tag changes, the wireless tag may not be able to communicate because it passes outside the communication range of the antenna of the communication device.

  Therefore, for example, Patent Document 1 discloses a means for optically detecting a wireless tag (responder) attached to a work (object), and a wireless tag based on position information of the wireless tag detected by this means. A system having means for moving the antenna or the antenna on the communication device (interrogator) side within a predetermined communication area is proposed. With such a system, even if the position of the wireless tag changes for each work to be transported, for example, communication can be performed because the antenna on the communication device side can be moved into the communication area.

JP 2001-156673 A

  However, in the system disclosed in Patent Document 1, the antenna is fixed after the antenna on the communication device side is moved to the communication area based on the position information of the optical detection means. Communication is performed when a wireless tag enters the communication range of the antenna. Although the antenna on the device side has been moved to an area where communication with the wireless tag is possible, there is a limit to the communication range of the antenna. Therefore, when communication with the wireless tag is performed while moving the workpiece, the wireless tag may pass through the antenna communication range in a short time and communication may fail. Therefore, in order to reliably perform communication between the communication apparatus and the wireless tag, it is conceivable to stop the work during communication. However, if the work is stopped every time communication is performed in this way, there arises a problem that work management processing is delayed.

  In the system disclosed in Patent Document 1, optical detection means (position recognizer) for detecting the position of a wireless tag attached to a work and an antenna are arranged with a distance. Then, the position of the wireless tag is detected by the optical detection means arranged on the upstream side, and the antenna on the communication device side is moved to an area where communication with the wireless tag can be performed based on this position information. An antenna position control device for moving the antenna is connected to the antenna. In such a system configuration, since a plurality of devices are arranged at a distance, there is a problem that the whole is increased in size. In addition, if the antenna position changed by the antenna position control device is inaccurate, the antenna position cannot be further corrected, and there is a problem that communication between the communication device and the wireless tag cannot be performed. End up.

  An object of the present invention is to solve the above-described problem and to provide a work management system including a communication device that can reliably communicate with a wireless tag.

  An object of the present invention is to provide an antenna drive unit that includes a wireless tag attached to a workpiece, a visual sensor that detects the workpiece, and an antenna that is used for communication with the wireless tag, and that changes at least one of the orientation and position of the antenna. And a communication device including a control unit that controls the antenna driving unit so that the antenna can communicate with the wireless tag based on information from the visual sensor.

  In the present invention, since the communication device includes the antenna and the visual sensor, the communication device can be made compact and the system can be downsized. In addition, since the communication device included in this system can overlap the communication range of the antenna and the imaging range of the visual sensor, it can reliably communicate with the wireless tag by controlling the antenna driving unit based on information from the visual sensor. Therefore, communication with the wireless tag can be reliably performed even when the work moves. It can be provided as a work management system without missing work management.

  The control unit may continuously control the antenna driving unit so that the antenna follows the position where the wireless tag moves. Further, the control unit may detect the workpiece with information from the visual sensor and control the antenna driving unit so that the wireless tag enters a communication range of the antenna. In addition, the antenna and the visual sensor are integrally arranged, and the control unit detects the workpiece with information from the visual sensor, and the visual sensor detects the workpiece at the center of the imaging range. Further, the antenna driving unit may be controlled.

  In addition, it is preferable that the control unit is set to continue the control of the antenna driving unit until information communication between the wireless tag and the communication device is completed. The visual sensor may detect a mark attached to the work for detecting the wireless tag.

  A tag attached to the workpiece may be included, and the tag may include the wireless tag and be marked with a mark for detecting the wireless tag. It is desirable that the mark is colored with a color having a higher brightness than the ground color of the workpiece. A vision chip can be used as the visual sensor.

  Further, the object is to drive an antenna that integrally arranges a visual sensor for detecting a work with a wireless tag and an antenna used for communication with the wireless tag, and changes at least one of the direction and position of the antenna. And a communication device including a control unit that controls the antenna driving unit so that the antenna can communicate with the wireless tag based on information from the visual sensor. Preferably, the control unit continuously controls the antenna driving unit to cause the antenna to follow a position where the wireless tag moves. The antenna driving unit can move the antenna by any one of a rotational movement operation, a horizontal movement operation, a vertical movement operation, or a combination of these operations.

  A tag attached to a work and detected by a visual sensor, including a wireless tag, and a mark that can be detected by the visual sensor is added to a peripheral portion of the wireless tag. Can be used for work management. The mark is preferably colored with a color having a higher brightness than the ground color of the workpiece.

  According to the present invention, for example, even when the work is moving, the communication apparatus can reliably communicate with the wireless tag attached to the work, so that work management without leakage can be performed efficiently.

  Hereinafter, a work management system according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a main configuration included in the work management system. An outline of the work management system will be described with reference to FIG.

  The work management system manages the work W by communicating with the wireless tag 2 using the communication device 1. The wireless tag 2 is attached to the work W. There is no particular limitation on the type of attaching the wireless tag 2 to the work W. For example, the wireless tag 2 may be affixed to the workpiece W itself, or the wireless tag 2 may be affixed to a packaging material that wraps the workpiece W. The main part of the wireless tag 2 is a wireless IC chip that stores various information related to the workpiece W, and stores information necessary for management of the identification code and the workpiece W. The wireless tag 2 and the communication device 1 transmit and receive information using radio waves. When a non-contact power transmission technique using microwaves or electromagnetic coupling is used, a more preferable system capable of communicating while supplying driving energy from the communication device 1 side to the wireless tag 2 side can be obtained. The wireless tag 2 has an antenna 3, and communicates with the communication apparatus 1 side via the antenna 3.

  The communication apparatus 1 includes a vision chip (also referred to as a vision sensor, a vision chip sensor, etc.) 11 as a visual sensor, an antenna 12, and an antenna driving unit 20 that changes at least one of the orientation and position of the antenna 12. The communication information processing unit 30 and the controller 10 for controlling them are included. The vision chip 11 images the workpiece W under the control of the controller 10 and supplies the image information to the controller 10. The vision chip 11 is a high-speed tracking vision chip, a vision chip as shown in IEICE Transactions D-II, Vol.J84-D-II, No.1, pp.75-82 (2001). It is preferable to use it. This vision chip integrates a plurality of photodetectors (for example, photodiodes) and a plurality of digital processing elements each corresponding one-to-one, and can be performed in parallel without requiring conventional scanning processing. It is a visual sensor that enables object tracking. Since the vision chip outputs the object extraction process and the calculation process of the information on the center of gravity of the object in parallel, the vision chip outputs the object in parallel, thereby enabling high-speed object tracking. On the other hand, for example, in a target tracking system using a conventional optical sensor such as a CCD, image information obtained by scanning all the pixels of the CCD is once transmitted to a work area such as an external RAM. The object was extracted by processing the image information, and the processing efficiency was poor. By using a vision chip, a vision chip can quickly perform a feedback operation such as following a moving object while imaging.

  The antenna 12 has a predetermined communicable range, and is designed to be able to communicate with each other when the wireless tag 2 enters this range. As will be shown later with reference to the drawings, the antenna 12 is formed integrally with the vision chip 11 described above. The antenna 12 is connected to an antenna driving unit 20. The antenna driving unit 20 includes an actuator and a moving mechanism driven by the actuator, and changes the direction and position of the antenna 12 under the control of the controller 10.

  The communication information processing unit 30 is a part that processes information related to the work W when communicating with the wireless tag 2. The communication information processing unit 30 can include, for example, a reading area that performs processing for reading information from the wireless tag 2 and a writing area that performs processing for writing information to the wireless tag 2. The controller 10 executes processing such as reading and writing of information when the communication information processing unit 30 is controlled to communicate with the wireless tag 2. The communication information processing unit 30 may be dedicated to reading and writing information. Accordingly, the communication device 1 becomes a read-only communication device or a write-only communication device.

  The controller 10 is a microcomputer mainly composed of a CPU, and controls the vision chip 11, the antenna driving unit 20, and the communication information processing unit 30 as a whole so that communication with the wireless tag 2 is smoothly executed. . In particular, the controller 10 of the communication apparatus 1 controls the antenna driving unit 20 based on image information from the vision chip 11 and changes the orientation and position of the antenna 12 so as to follow the moving workpiece W. Furthermore, a more specific form of the work management system is shown in the following examples. In addition, the same code | symbol is attached | subjected to the site | part corresponding to the structure shown in FIG.

  FIG. 2 is a diagram illustrating the work management system according to the first embodiment. The workpiece W having the same shape is conveyed rightward by the conveyor 5, and the communication device 1 communicates with the wireless tag 2 attached to the workpiece W to manage the workpiece W. From (a) to (c), the state of the work W to be conveyed and the communication device 1 operating in response thereto is shown as time elapses.

  The vision chip 11 is disposed on the antenna 12. A rotary table 21 as one form of the antenna drive unit 20 is disposed below the antenna 12. A drive motor and a gear mechanism (not shown) are provided inside the rotary table 21, and the rotation is controlled by the controller 10. Note that the communication device 1 shown in FIG. 2 is schematically shown in a state where the controller 10 is separated so that the connection relationship between the controller 10 and other parts can be easily confirmed. The controller 10 can be integrated with the communication device 1 to be a compact device by being arranged on the back of the antenna 12 or the lower part of the rotary table 21.

  In FIG. 2, the communicable range AR of the antenna 12 is indicated by a broken line. The communicable range AR is set on the assumption that the workpiece W is conveyed by the conveyor 5. The imaging range by the vision chip 11 is set so as to overlap the communicable range AR of the antenna 12. The controller 10 processes the information of the image captured by the vision chip 11 and detects the position of the workpiece W. Then, the controller 10 controls the rotary table 21 based on the image information of the vision chip 11 so that the antenna 12 can communicate with the wireless tag 2 side.

  For example, the controller 10 confirms (detects) the work W with the image data of the vision chip 11 and then starts communication with the wireless tag 2 side, monitors the reception state by the antenna 12 and within the communicable range AR. The driving of the rotary table 21 is controlled so that the For example, the controller 10 controls the driving of the rotary table 21 so that the workpiece W is positioned at the center of the image detected by the vision chip 11. If it does in this way, it will be in the state which always images the workpiece | work W in the center of the imaging range of the vision chip 11. FIG. As described above, the imaging range of the vision chip 11 is set to overlap the communicable range AR of the antenna 12, and the vision chip 11 is fixed to the antenna 12 and rotates integrally. Therefore, when the work W is positioned at the center of the image detected by the vision chip 11, it is possible to form a state in which the work W always exists within the communicable range AR of the antenna 12. It should be noted that the vision chip 11 and the antenna 12 are not limited to being integrally disposed as described above, but may be separately disposed as long as they are linked in the same manner.

  Since the controller 10 performs the control as described above, the direction of the antenna 12 is changed so as to follow the movement of the workpiece W as shown in FIG. That is, even when the workpiece W is moved to the conveyor 5 and is in a moving state, the communication device 1 can take a long time to communicate with the wireless tag 2. Therefore, the work management system shown here can reliably perform communication between the communication device 1 and the wireless tag 2. Thus, since reading and writing of information can be performed between the communication device 1 and the wireless tag 2 without omission, accurate work management can be performed.

  In particular, by setting the controller 10 to continuously control the driving of the rotary table 21 as described above until the communication with the wireless tag 2 is completed, work management with no leakage is ensured. In addition, when the communication with the wireless tag 2 is completed in a short time under such control, the rotary table 21 is returned to the initial position as shown in FIG. Can speed up the process. Further, in a place where the radio wave environment is not good due to the influence of radio wave interference or the like, accurate communication can be performed by ensuring a long communication time with the wireless tag 2 and accurate work management. Furthermore, since the communication between the communication device 1 and the wireless tag 2 can be reliably performed while the workpiece W is being conveyed, workpiece management can be performed more quickly than when the workpiece W is stopped and reading is performed. Furthermore, according to the communication apparatus 1, even if the conveyance speed of the workpiece W changes, the controller 10 adjusts the rotation speed of the rotary table 21 to cope with it, so that the communication with the wireless tag 2 can be reliably performed.

  In addition, since the controller 10 confirms the workpiece W based on the image information of the vision chip 11 and starts substantial control, even if the conveyor 5 transports the workpiece W irregularly, it is useless. It can respond without any problems. Further, by setting the controller 10 to start transmission of radio waves after confirming the workpiece W with the vision chip 11, it is possible to suppress unnecessary radio waves from being transmitted.

  FIG. 3 is a diagram illustrating the work management system according to the second embodiment. The second embodiment is a work management system that can cope with conveyance of workpieces W1 to W4 having different shapes. In FIG. 3 as well, parts corresponding to those in the configuration shown in FIG.

  The turntable 21 of the communication device 1 is configured so that the direction of the antenna 12 can be changed (rotated) and moved in the vertical direction. Therefore, even if the height of the workpiece W changes, it can be adjusted so that the wireless tag 2 enters the communication range by changing the height position of the antenna 12.

  A mark 4 is added to the peripheral portion of the wireless tag 2 attached to the work W. This mark 4 is added by the vision chip 11 so that the position of the wireless tag 2 can be easily detected. The communication device 1 in FIG. 3 uses information regarding the position of the center of gravity of the mark 4 from the vision chip 11 for detecting the workpiece W and detecting the position of the wireless tag 2. That is, the controller 10 confirms the work W from the image information of the vision chip 11 and also detects which position of the work W the wireless tag 2 is attached to. The controller 10 of the present embodiment controls the rotary table 21 to rotate the direction of the antenna 12 so that the wireless tag 2 falls within the communication range, and changes the height position of the antenna 12 as necessary.

  As described above, the communication device 1 can reliably communicate with the wireless tag 2 even in a situation where the workpieces W having different shapes are irregularly conveyed in the system of the second embodiment. In the example shown in FIG. 3, a label (tag) L in which the wireless tag 2 is arranged at the center is attached to the surface of the work W. The periphery of the label L is colored with a color having a higher brightness than the ground color of the workpiece W. This colored portion becomes the mark described above. By preparing such a label L and attaching it to the work W, it is possible to make the work to be controlled symmetrically by the work management system. It is desirable that the mark 4 portion of the label L is colored with a color whose brightness is higher than the background color of the workpiece. When colored in this way, it becomes easy to detect the binarized value of the output of the photodetector by the vision chip 11 that performs parallel processing. Further, if the label L is colored with a color whose brightness is higher than the background color of the work as a whole, the entire label L functions in the same manner as the mark 4, and thus the mark may be attached in this way.

  As described above, a form in which the label L is pasted on the work W is convenient, but the wireless tag 2 may be embedded at a predetermined position such as a cardboard for packing the work and a mark may be printed in advance on the periphery thereof. Although FIG. 3 shows an example in which the mark 4 is formed in an annular shape so as to surround the peripheral portion of the wireless tag 2, the formation of the mark 4 is not limited to this. The mark may be formed by a plurality of points arranged on the periphery of the wireless tag 2 as long as it can be detected by the vision chip 11. 3 can adjust the height position of the antenna 12, and therefore can reliably communicate with the wireless tag 2 even when the movement path of the workpiece W is sloped.

  FIG. 4 is a diagram illustrating the work management system according to the third embodiment. The third embodiment is a work management system that performs communication with the wireless tag 2 while moving the communication device 1 in parallel with the work W. In FIG. 4 as well, parts corresponding to those shown in FIG.

  The system shown in FIG. 4 realizes a configuration in which the entire communication device 1 is moved to cause the wireless tag 2 to follow the antenna 12 unlike the above-described embodiment. The antenna driving unit 20 shown in FIG. 1 includes a carriage 22 having wheels 23 and a rail 25 for guiding the carriage 22. A motor or gear mechanism (not shown) is built in the carriage 22, and the drive is controlled by the controller 10.

  In this system, for example, the communication apparatus 1 waits for the work W to be conveyed at the initial position PR. When the controller 10 detects the workpiece W from the image information from the vision chip 11, the controller 10 controls the carriage 22 to follow the workpiece W to communicate with the wireless tag 2. Also in this system, the communication time with the wireless tag 2 can be made long as in the above-described embodiment. Therefore, the communication apparatus 1 can reliably communicate with the wireless tag 2 and perform accurate work management without reading and writing failures.

  In the system shown in FIG. 4, when the controller 10 attempts communication with the wireless tag 2 at the initial position PR and performs necessary communication, the carriage 22 is not moved, and only when communication is insufficient. It is possible to control the carriage 22 to move so as to follow the wireless tag 2. In this way, since the carriage 22 is moved only when necessary, useless operations can be omitted. Note that the communication device 1 shown in FIG. 4 illustrates a state where the controller 10 is fixed to the back of the antenna 12 and is compactly integrated.

  FIG. 5 is a flowchart illustrating an example of a routine executed by the controller 10 of the communication device 1. This flowchart comprehensively shows the processes common to the above three embodiments. The controller 10 periodically images the vision chip 11 toward the conveyor 5 (S101), analyzes the image information from the vision chip 11 and monitors the passage of the workpiece W (S102).

  When the controller 10 detects the workpiece W (S103), the controller 10 further controls the antenna driving unit 20 so that the wireless tag 2 enters the communicable range AR of the antenna 12 based on the image information obtained from the vision chip 11 (S104). . In this case, the work W may be controlled so as to enter the communicable range AR to substantially secure the communication between the wireless tag 2 and the communication device 1, or the case where the mark 4 described above is used. In addition, it may be controlled to ensure communication while accurately detecting the position of the wireless tag 2.

  The controller 10 controls the antenna driving unit 20 to change the antenna 12 to the optimum direction (and position) and communicate with the wireless tag 2 (S105). The controller 10 continues control to follow the wireless tag 2 until the communication information processing unit 30 completes reading and writing of information with the wireless tag 2. Therefore, communication with the wireless tag 2 can be reliably performed. When the communication with one workpiece W is completed (S106), the controller 10 ends the processing according to this flowchart. Then, the antenna drive unit 20 is controlled to return to the initial position and return to the state of monitoring the next workpiece W.

  As described above, according to the work management system of the embodiment, a work with a wireless tag can be efficiently managed without omission. In particular, accurate management can be performed even when the workpiece W is moving. In addition, since the communication device 1 used in the system has the vision chip 11 fixed on the antenna 12, the work can be detected efficiently by overlapping the communication range and the imaging range. Further, since the communication device 1 is made compact in size, the equipment can be downsized. In addition, although the case where the mark 4 is added to the wireless tag 2 in the second embodiment is shown, it is needless to say that the same mark may be attached to the first and third embodiments.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to the specific embodiment, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible. The workpieces in the present invention are not limited to articles to be transported, and include, for example, everything such as vehicles such as cars and trains, people, and animals. The work of the present invention includes all objects managed or monitored by a communication device by attaching a wireless tag.

It is a block diagram showing the main composition contained in the work management system of an embodiment. It is the figure shown about the work management system of Example 1. FIG. It is the figure shown about the work management system of Example 2. FIG. It is the figure shown about the work management system of Example 3. It is the flowchart which showed an example of the routine which the controller of a communication apparatus performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication apparatus 2 Wireless tag 3 Antenna 5 Conveyor 10 Controller (control part)
11 Vision chip (visual sensor)
12 antenna 20 antenna drive unit 30 communication information processing unit W work AR communication possible range

Claims (14)

A wireless tag attached to the workpiece;
Based on information from the visual sensor that includes a visual sensor that detects the workpiece and an antenna that is used for communication with the wireless tag, and that changes at least one of the orientation and position of the antenna, A communication device including a control unit that controls the antenna driving unit so that the antenna can communicate with the wireless tag;
A work management system characterized by including. The work management system according to claim 1, wherein the control unit continuously controls the antenna driving unit to cause the antenna to follow a position where the wireless tag moves. The work according to claim 2, wherein the control unit detects the work with information from the visual sensor and controls the antenna driving unit so that the wireless tag falls within a communication range of the antenna. Management system. The antenna and the visual sensor are integrally arranged, and the control unit detects the workpiece with information from the visual sensor, and the visual sensor detects the workpiece at the center of the imaging range. The work management system according to claim 2, wherein the antenna drive unit is controlled. The work management system according to claim 2, wherein the control unit continues the control of the antenna driving unit until communication of information is completed between the wireless tag and the communication device. The work management system according to claim 1, wherein the visual sensor detects a mark attached to the work for detection of the wireless tag. 6. The workpiece according to claim 1, further comprising a tag attached to the workpiece, the tag including the wireless tag and a mark for detecting the wireless tag. Management system. The work management system according to claim 7, wherein the mark is colored with a color whose brightness is higher than a ground color of the work. 9. The work management system according to claim 1, wherein the visual sensor is a vision chip. A visual sensor that detects a work with a wireless tag and an antenna used for communication with the wireless tag, and an antenna driving unit that changes at least one of the orientation and position of the antenna, and the visual sensor And a control unit that controls the antenna driving unit so that the antenna can communicate with the wireless tag based on information from the communication device. The communication device according to claim 10, wherein the control unit continuously controls the antenna driving unit to cause the antenna to follow a position where the wireless tag moves. The communication apparatus according to claim 10 or 12, wherein the antenna driving unit moves the antenna by any one of a rotational movement operation, a horizontal movement operation, and a vertical movement operation, or a combination of these operations. A tag attached to a workpiece and detected by a visual sensor,
A tag for a work management system, comprising a wireless tag, wherein a mark detectable by the visual sensor is attached to a peripheral portion of the wireless tag. 14. The tag for a work management system according to claim 13, wherein the mark is colored with a color whose brightness is higher than the ground color of the work.

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