Material detection system

Abstract

To provide a material detection system that can detect materials without using material identification information. [Solution] The material detection system according to the present disclosure is a material detection system for determining whether a material is placed in a predetermined location, comprising: a transmitting unit that transmits a wireless signal; a receiving unit that receives the wireless signal transmitted from the transmitting unit via a wireless communication path; and a calculation unit that determines whether the material is placed in a predetermined location by detecting that the material attenuates the wireless signal on the wireless communication path based on a change in the signal strength of the wireless signal received by the receiving unit.

Description

Technical Field

[0001] The present disclosure relates to a material detection system.

Background Art

[0002] In recent years, technologies for identifying skids have been disclosed in automobile production factories and the like. For example, the conveyance cargo handling specifying device according to Patent Document 1 identifies a skid being conveyed by a conveyance vehicle (forklift) and a skid not being conveyed. In Patent Document 1, an RFID (Radio Frequency Identification) tag is attached to each surface of a pallet, and the conveyance vehicle is provided with a reader / writer for reading information from the RFID tag and a skid specifying unit. The skid specifying unit aggregates data received from the RFID tag by the reader / writer at regular intervals, and specifies the conveyed skid based on the response frequency and intensity of the RFID tag per unit time.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The conveyance cargo handling specifying device according to Patent Document 1 attaches RFID tags to each surface of the pallet. However, the pallets used in the logistics process are diverse, and the owners of the pallets include both inside and outside the company. Therefore, in the factory, there may be pallets without identification tags, or even if the pallets have identification tags, their communication standards may vary for each pallet. Under such circumstances, there is a risk that materials cannot be identified using the identification information of materials including pallets.

[0005] This disclosure is made to solve these problems and aims to provide a material detection system that can detect materials without using material identification information. [Means for solving the problem]

[0006] The material detection system according to this disclosure is a material detection system for determining whether a material is placed in a predetermined location, and comprises: a transmitting unit that transmits a wireless signal; a receiving unit that receives the wireless signal transmitted from the transmitting unit via a wireless communication path; and a calculation unit that determines whether the material is placed in a predetermined location by detecting that the material attenuates the wireless signal on the wireless communication path based on a change in the signal strength of the wireless signal received by the receiving unit. As a result, when the material is placed in a predetermined location, the material attenuates the wireless signal, and the calculation unit detects the attenuation, the material detection system can detect the material without using material identification information. [Effects of the Invention]

[0007] According to this disclosure, a material detection system can be provided that can detect materials without using material identification information. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram showing the configuration of the material detection system 1 according to this embodiment. [Figure 2] Figure 2 shows an example of the signal strength information stored in the signal strength master 7. [Figure 3] Figure 3 shows an example of the screen displayed by the material availability indicator 9. [Figure 4] Figure 4 is a schematic diagram showing an example of the configuration of the material detection system 1. [Figure 5] Figure 5 is a schematic diagram showing an example of the configuration of the material detection system 1. [Figure 6] Figure 6 is a schematic diagram showing an example of the configuration of the material detection system 1. [Modes for carrying out the invention]

[0009] Embodiments relating to this disclosure will be described below with reference to the drawings. In these embodiments, "materials" refers to parts for finished products such as automobiles, and parts boxes containing such parts. Materials also include pallets. That is, materials include pallets on which the parts and parts boxes are placed, as well as empty pallets.

[0010] Pallets may be made of metal, plastic, or wood. Alternatively, a pallet may contain metal, plastic, or wood as a constituent material. Furthermore, a pallet may have a portion made of metal, plastic, or wood. Here, a metal pallet is, for example, made of iron or aluminum. Additionally, a pallet may be a box pallet, a cage pallet, or a flat pallet. A pallet may also be a skid.

[0011] In this embodiment, when a wireless signal attempts to pass through the material, at least a portion of the material is made of a material that attenuates the wireless signal. To achieve this function, a portion of the material may be made of a material that shields or blocks the wireless signal. Alternatively, at least a portion of the material may be made of a material that reflects or absorbs the wireless signal that strikes the material. Furthermore, at least a portion of the material in this embodiment may be made of a material that reduces the signal intensity of the wireless signal.

[0012] Figure 1 is a block diagram showing the configuration of the material detection system 1 according to this embodiment. The material detection system 1 comprises a transmitting unit 2, a receiving unit 3, a signal processing unit 4, a calculation unit 5, a data storage unit 6, a signal strength master 7, a material presence / absence display processing unit 8, a material presence / absence display unit 9, and a raised structure 10 (see Figures 4 and 5). The material detection system 1 is a system that determines (detects) whether materials are placed in a predetermined location. Here, the "predetermined location" where materials are placed may be any of the following locations: a predetermined flat area, inside a rack, on a belt conveyor, on the forks of a forklift, or any other location within the logistics warehouse. Hereafter, the location where materials are placed will be referred to as a storage area. In addition to materials, each component of the material detection system 1 may be placed within the storage area. The storage area targeted by the material detection system 1 may be one or multiple locations.

[0013] The transmitter 2 is a device that transmits a wireless signal within a certain range according to a predetermined communication standard. The wireless signal transmitted by the transmitter 2 may be a radio wave or an infrared light. For example, the communication standard for the wireless signal adopted by the transmitter 2 may be Bluetooth®, BLE (Bluetooth Low Energy)®, or ZigBee®. The transmitter 2 may also be a short-range wireless communication device such as a beacon. The transmitter 2 may include information about the location it is targeting in the wireless signal, may include identification information of the transmitter 2 in the wireless signal, or may not include any information in the wireless signal.

[0014] The signal strength of the wireless signal transmitted by the transmitting unit 2 shall be such that the receiving unit 3 can receive the wireless signal if there are no obstacles in the wireless communication path between the transmitting unit 2 and the corresponding receiving unit 3. In other words, the signal strength of the wireless signal transmitted by the transmitting unit 2 may be reduced to such an extent that the receiving unit 3 cannot receive the wireless signal if there are obstacles in the wireless communication path.

[0015] The transmission unit 2 may be plural or may be one. That is, the transmission unit 2 may be provided for each storage location, or one transmission unit 2 may be provided to target a plurality of storage locations.

[0016] The transmission unit 2 may be installed on any of the floor surface, wall surface, or ceiling of the storage location, or may be suspended from above the storage location. Also, the transmission unit 2 may be installed on the side of the location where materials are arranged in the storage location. When the transmission unit 2 is installed on the floor surface of the storage location, the transmission unit 2 may be installed on the floor surface or may be embedded in the storage floor. Even when the transmission unit 2 is embedded, the receiving unit 3 corresponding to the transmission unit 2 shall be able to receive the radio signal from the transmission unit 2 when there is no obstacle on the radio communication path. For example, when the transmission unit 2 is installed on the floor surface of the storage location, the materials targeted by the transmission unit 2 may be arranged directly above the transmission unit 2. In other words, the transmission unit 2 may be arranged on the floor surface facing the bottom surface of the material.

[0017] The receiving unit 3 is a device that receives the radio signal sent from the transmission unit 2 via the radio communication path. That is, the receiving unit 3 has a function of receiving the radio signal sent by the transmission unit 2 according to a predetermined communication standard. When the transmission unit 2 includes the information of the storage location or the identification information of the transmission unit 2 in the radio signal, the receiving unit 3 can receive these information together by receiving the radio signal. The receiving unit 3 sends the received radio signal to the signal processing unit 4. The receiving unit 3 is, for example, a beacon receiver.

[0018] The receiving unit 3 may be plural or may be one. That is, the receiving unit 3 may be provided for each storage location, or one receiving unit 3 may be provided to target a plurality of storage locations. When the number of receiving units 3 is less than the number of transmission units 2, the transmission unit 2 may include the information of the storage location targeted by the transmission unit 2 or the identification information of the transmission unit 2 in the radio signal.

[0019] The receiving unit 3 may be suspended from above the storage area, or may be installed on any of the ceiling, the floor surface, or the wall surface of the storage area. Further, the receiving unit 3 may be installed on the side of the material placement location in the storage area. Here, it is assumed that materials targeted by the transmitting unit 2 and the receiving unit 3 are arranged on the wireless communication path between the receiving unit 3 and the transmitting unit 2 corresponding to the receiving unit 3. That is, the receiving unit 3 is provided such that the target material is arranged on the wireless communication path between the receiving unit 3 and the transmitting unit 2 corresponding to the receiving unit 3.

[0020] For example, when the transmitting unit 2 is installed on the floor surface of the storage area, the receiving unit 3 corresponding to the transmitting unit 2 may be suspended from above the storage area. In this case, the target material is arranged on the wireless communication path between the transmitting unit 2 and the receiving unit 3. Further, for example, when the transmitting unit 2 is installed on the side of the material placement location in the storage area, the receiving unit 3 corresponding to the transmitting unit 2 may be installed on the opposite side through the material. In this case, the target material is arranged on the wireless communication path between the transmitting unit 2 and the receiving unit 3.

[0021] The signal processing unit 4 is a software program that performs predetermined signal processing on the wireless signal received by the receiving unit 3. The signal processing unit 4 extracts, for example, information on the signal strength of the wireless signal received by the receiving unit 3. In addition, the signal processing unit 4 may extract information on the storage area and the identification information of the transmitting unit 2 included in the wireless signal received by the receiving unit 3 from the wireless signal. The signal processing unit 4 transmits the information to the calculation unit 5. The signal processing unit 4 may be provided for each receiving unit 3, may be provided one for a plurality of receiving units 3, or may be provided one for all receiving units 3.

[0022] The calculation unit 5 is a software program that receives information about the wireless signal received by the receiving unit 3 from the signal processing unit 4 and determines whether the materials are placed in the storage area based on the change in the signal strength of the wireless signal. In other words, the calculation unit 5 determines whether the materials are placed in the predetermined location based on the change in the signal strength of the wireless signal received by the receiving unit 3. The calculation unit 5 may be provided for each receiving unit 3, for multiple receiving units 3, or for all receiving units 3. The calculation unit 5 transmits the determination result to the material presence / absence display processing unit 8. For example, the calculation unit 5 transmits the determination result to the material presence / absence display processing unit 8 as to whether the materials are placed in each storage area.

[0023] The calculation unit 5 determines whether the material is placed in a predetermined location by detecting that the material attenuates the wireless signal on the wireless communication path. That is, when the material is placed in the storage area, the material is placed on the wireless communication path between the transmitting unit 2 and the receiving unit 3. Here, at least a part of the material in this embodiment is made of a material that attenuates wireless signals. Therefore, when the material is placed in the storage area, the signal strength of the wireless signal received by the receiving unit 3 decreases compared to when the material is not placed in the storage area. The calculation unit 5 determines whether the material is placed in the storage area based on the decrease in the signal strength of the wireless signal.

[0024] Here, the signal strength of the wireless signal received by the receiving unit 3 may not decrease as much as it would be if the material were not placed in the storage area, due to the material being placed on the wireless communication path between the transmitting unit 2 and the receiving unit 3. In other words, the calculation unit 5 may determine whether the material is placed in the storage area when the signal strength of the wireless signal decreases due to the material.

[0025] The calculation unit 5 may determine, for example, that materials have been placed in the locations corresponding to the transmitting unit 2 and the receiving unit 3 when the signal strength of the wireless signal received by the receiving unit 3 falls below a predetermined threshold relative to the signal strength of the wireless signal sent out by the transmitting unit 2. In this case, the calculation unit 5 may also determine that materials have been placed in the location when the signal strength of the wireless signal received by the receiving unit 3 remains below the threshold for a predetermined period of time.

[0026] The data storage unit 6 is composed of a storage device such as a hard disk or flash memory. The data storage unit 6 may store data related to storage locations, data related to materials, data related to the transmission unit 2, and data related to the reception unit 3. Specifically, the calculation unit 5 may store identification information for each storage location, identification information for the transmission unit 2, and identification information for the reception unit 3. The data storage unit 6 may also store this information in association with other information. For example, the data storage unit 6 may store the correspondence between each storage location and the corresponding transmission unit 2 and reception unit 3 as data.

[0027] The signal strength master 7 is composed of a storage device such as a hard disk or flash memory. The signal strength master 7 stores information regarding the signal strength of the wireless signal received by the receiving unit 3 when materials are placed in each storage location. For example, the signal strength master 7 may store threshold information regarding the signal strength of the wireless signal received by the receiving unit 3. Specifically, the signal strength master 7 may store threshold information indicating how much the signal strength of the wireless signal received by the receiving unit 3 should decrease compared to the signal strength of the wireless signal sent by the transmitting unit 2 before it can be determined that materials have been placed in the storage location.

[0028] Figure 2 shows an example of the information stored by the signal strength master 7. Figure 2 is an example of the information regarding signal strength stored by the signal strength master 7. In Figure 2, it is assumed that there are two storage locations where materials are placed. The signal strength master 7 also stores the ratio threshold of the signal strength of the radio signal received by the receiving unit 3 at each storage location. That is, the signal strength master 7 stores the threshold for the ratio of the signal strength of the radio signal received by the receiving unit 3 to the signal strength of the radio signal sent out by the transmitting unit 2. For example, in storage location A in Figure 2, when the signal strength of the radio signal received by the receiving unit 3 becomes 30% of the signal strength of the radio signal sent out by the transmitting unit 2, the calculation unit 5 determines that materials have been placed at storage location A. Similarly, in storage location B, when the signal strength of the radio signal received by the receiving unit 3 becomes 25% of the signal strength of the radio signal sent out by the transmitting unit 2, the calculation unit 5 determines that materials have been placed at storage location B.

[0029] Returning to Figure 1, let's continue the explanation of the configuration of the material detection system 1. The material presence / absence display processing unit 8 is a program that receives the determination result from the calculation unit 5 and generates content to be displayed on the material presence / absence display unit 9. For example, when the calculation unit 5 receives the determination result of whether or not materials are placed in each storage area, the material presence / absence display processing unit 8 causes the material presence / absence display unit 9 to display whether or not materials are placed in each storage area. The material presence / absence display unit 9 is a display device including a liquid crystal panel or organic electroluminescence, and is a means for displaying necessary information to the user. The material presence / absence display unit 9 displays the display content generated by the material presence / absence display processing unit 8.

[0030] Figure 3 shows an example of the screen displayed by the material presence / absence display unit 9. In Figure 3, it is assumed that there are two storage locations, storage location A and storage location B. The material presence / absence display unit 9 may also display whether or not materials are placed in storage location A as "present" or "absent," and whether or not materials are placed in storage location B as "present" or "absent." In Figure 3, the calculation unit 5 has determined that no materials are placed in storage location A, so the material presence / absence display unit 9 displays "absent" for storage location A, and it has determined that materials are placed in storage location B, so the material presence / absence display unit 9 displays "present" for storage location B.

[0031] The raised structure 10 has a structure for placing materials on it in a storage area. Specifically, the raised structure 10 has a horizontal surface on which materials are placed. The raised structure 10 may also have a support part that supports the mounting base. If the raised structure 10 has a support part, the support part may support the mounting base at three points or at four points. The support part of the raised structure 10 may also be formed integrally with the mounting base by bending the end of the mounting base. The raised structure 10 may or may not be fixed to the floor surface of the storage area. In other words, the raised structure 10 may or may not be movable. The raised structure 10 may be, for example, a pedestal or a stand.

[0032] In the raising structure 10, at least the surface on which the material is placed, i.e., the mounting platform, may be made of a material that does not attenuate wireless signals. For example, the raising structure 10 may be made of plastic or wood. In the raising structure 10, the area of ​​the mounting surface on the mounting platform may be larger than the bottom area of ​​the material placed on it, the same as the bottom area, or smaller than the bottom area.

[0033] If the transmitting unit 2 is installed on the floor of the storage area and the raising structure 10 is equipped with support legs that support the mounting base, the raising structure 10 may accommodate the transmitting unit 2. That is, the raising structure 10 may be formed so as to be able to cover the transmitting unit 2. Also, if the receiving unit 3 is installed on the floor of the storage area, the raising structure 10 may accommodate the receiving unit 3. That is, the raising structure 10 may be formed so as to be able to cover the receiving unit 3.

[0034] Here, an example of the configuration of the material detection system 1 will be explained using a drawing. Figure 4 is a schematic diagram showing an example of the configuration of the material detection system 1. In Figure 4, the storage area for materials is a flat area, and there are two storage areas. These storage areas will be referred to as storage area A and storage area B. In Figure 4, the material detection system 1 is provided with a pair of transmitters 2 and receivers 3 for each storage area. Specifically, a transmitter 2A and a receiver 3A are located in storage area A, and a transmitter 2B and a receiver 3B are located in storage area B. The transmitters 2 are located on the floor surface of the storage area. Specifically, the transmitters 2 are positioned so that the materials targeted by the transmitters 2 are located directly above them. The receivers 3 are suspended from above the storage area.

[0035] In Figure 4, the material detection system 1 has a raised structure 10. Specifically, raised structure 10A is placed in storage area A, and raised structure 10B is placed in storage area B. The area of ​​the mounting surface on the platform of the raised structure 10 is larger than the bottom area of ​​the material. Furthermore, the raised structure 10 is structured to accommodate the transmitting unit 2 inside, and the transmitting unit 2 is housed within it.

[0036] In Figure 4, no materials are placed in storage area A. Therefore, the signal strength of the wireless signal received by the receiver 3A is not lower than the signal strength of the wireless signal sent out by the transmitter 2A. For this reason, the calculation unit 5 determines that no materials are placed in storage area A. On the other hand, materials are placed in storage area B. Therefore, the signal strength of the wireless signal received by the receiver 3B is lower than the signal strength of the wireless signal sent out by the transmitter 2B. For this reason, the calculation unit 5 determines that materials are placed in storage area B.

[0037] Other examples of the configuration arrangement of the material detection system 1 will be described. Figures 5 and 6 are schematic diagrams showing an example of the configuration arrangement of the material detection system 1. In contrast to the material detection system 1 in Figure 4, in Figures 5 and 6, the receiving unit 3 is located on the floor. In Figure 5, no materials are placed in the storage area. Therefore, the signal strength of the wireless signal received by the receiving unit 3 is not lower than the signal strength of the wireless signal sent out by the transmitting unit 2. Thus, the calculation unit 5 determines that no materials are placed in storage area A. On the other hand, in Figure 6, materials are placed in the storage area. Therefore, the signal strength of the wireless signal received by the receiving unit 3 is lower than the signal strength of the wireless signal sent out by the transmitting unit 2. Thus, the calculation unit 5 determines that materials are placed in the storage area.

[0038] As described above, the material detection system 1 according to this embodiment can determine whether a material is placed in a predetermined location based on changes in the signal strength of the wireless signal received by the receiver 3, by placing the material on the wireless communication path between the transmitter 2 and the receiver 3. In automobile production plants and the like, it is conceivable to attach identification tags to materials when detecting them, but within the factory, there may be materials that do not have identification tags, or even if materials have identification tags, the communication standards may differ. In such cases, attaching identification tags, beacons, GPS (Global Positioning System), etc., with a unified communication standard to all materials would contribute to increased management costs. Under such circumstances, there is a risk that materials cannot be identified using the material's identification information.

[0039] However, the material detection system 1 according to this embodiment can detect materials without using material identification information. That is, the material detection system 1 can detect materials without attaching identification tags or the like to all of them. This is achieved by placing the materials on the wireless communication path between the transmitting unit 2 and the receiving unit 3, causing the materials to attenuate the wireless signal from the transmitting unit 2, and the calculation unit 5 detecting this attenuation. In other words, the material detection system 1 according to this embodiment detects materials by utilizing the attenuation effect of the wireless signal by the material itself, since a part of the material is formed from a material that attenuates wireless signals.

[0040] Furthermore, even if the material targeted by the material detection system 1 is a pallet containing metal as a constituent material, the material detection system 1 can still detect the pallet. In particular, in automobile production plants, automobile parts are sometimes stored and transported on pallets containing metal as a constituent material. In such cases, if an attempt is made to manage the pallet using wireless signals within the factory without attaching identification tags to the pallet, the pallet may attenuate the wireless signal, making it impossible to correctly detect the pallet. The material detection system 1 according to this embodiment detects the pallet by utilizing the attenuation effect of the wireless signal by the pallet, and therefore can manage the pallet using wireless signals.

[0041] Furthermore, by placing the transmitter 2 of the material detection system 1 on the floor surface of the storage area, it becomes easier to detect the materials. In other words, by providing the transmitter 2 around the material storage area, the distance between the materials and the transmitter 2 becomes shorter, and the attenuation effect of the wireless signal by the materials becomes more pronounced. As a result, the calculation unit 5 can more easily detect the materials. If the transmitter 2 is placed on the floor surface facing the bottom surface of the materials, the attenuation effect can be further enhanced.

[0042] Furthermore, in the material detection system 1 according to this embodiment, the transmitting unit 2 is housed inside the raised structure 10, and the raised structure 10 is movable. In this case, since the raised structure 10 can be placed anywhere within the storage area, the location of the transmitting unit 2 housed inside it can also be changed arbitrarily. Therefore, the position of the transmitting unit 2 can be easily changed.

[0043] It should be noted that the present invention is not limited to the embodiments described above, and can be modified as appropriate without departing from the spirit of the invention. [Explanation of Symbols]

[0044] 1. Material detection system, 2. Transmitter, 3. Receiver, 4. Signal processing unit, 5. Calculation unit, 6. Data storage unit, 7. Signal strength master, 8. Material presence / absence display processing unit, 9. Material presence / absence display unit, 10. Raised structure

Claims

1. A material detection system that determines whether materials are placed in a designated location, A transmitting unit that sends out wireless signals, A receiving unit that receives the wireless signal transmitted from the transmitting unit via a wireless communication path, The system includes a calculation unit that determines whether the material is placed in a predetermined location by detecting that the material attenuates the wireless signal on the wireless communication path based on a change in the signal strength of the wireless signal received by the receiving unit. Material detection system.

2. The aforementioned material is a pallet containing metal as a constituent material. The material detection system according to claim 1.

3. The transmitting unit is placed on the floor surface of the predetermined location. The material detection system according to claim 1.

4. The transmitting unit is positioned on the floor surface opposite the bottom surface of the material. The material detection system according to claim 3.

5. The material detection system further includes a raised structure for placing the material, The transmitting unit is housed in the raised structure. The material detection system according to claim 3 or 4.

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