Apparatus, system, and method for indoor positioning

Abstract

An apparatus, system and method for indoor positioning are provided. The apparatus is configured to move in an indoor area, the indoor area containing a plurality of objects, each object being provided with a tag storing at least an object identification of the object provided with the object; and the apparatus is further configured to, upon detecting one or more objects, acquire the object identification in the tag of each detected object, and transmit a wireless signal containing the object identification, the wireless signal being used to determine the position of the apparatus and the position of the object corresponding to the object identification.

Description

TECHNICAL FIELD

[0001] The present application relates generally to the technical field of indoor positioning, and in particular to an apparatus for indoor positioning and a system comprising the apparatus, and to a method for indoor positioning. BACKGROUND

[0002] Positioning technology can provide location-based services, which are required in many fields, for example, in systems for navigation and trajectory tracking. Currently, outdoor positioning can rely on global satellite navigation systems (GNSS) to achieve. However, GNSS cannot provide indoor positioning services because satellite signals are difficult to penetrate buildings and indoor signal coverage is poor.

[0003] Therefore, indoor positioning technology is a research hotspot in recent years. Although there are some indoor positioning systems in the prior art, these existing indoor positioning systems still have problems such as high cost, low positioning efficiency, and complex system structure.

[0004] Therefore, there is an urgent need for a technical solution that overcomes one or more aspects of the above-mentioned defects. SUMMARY

[0005] In view of the above-mentioned problems in the prior art, according to an embodiment of the first aspect of the present application, an apparatus for indoor positioning is provided, the apparatus is configured to move in an indoor area, the indoor area contains a plurality of objects, each object is provided with a tag storing at least an object identifier of the object provided; and the apparatus is further configured to, in the case of detecting one or more objects, acquire the object identifier in the tag of each detected object, and send a wireless signal containing the object identifier, the wireless signal being used to determine the position of the apparatus and the position of the object corresponding to the object identifier.

[0006] According to an embodiment of the second aspect of the present application, a system for indoor positioning is provided, comprising: an apparatus as described above, for detecting objects in an indoor area, reading the object identifier of the detected object, and sending a wireless signal containing the object identifier; and a control unit, which is wirelessly connected with the apparatus and receives the wireless signal, calculates the position of the apparatus based on the wireless signal and associates the position with the position of the object corresponding to the object identifier.

[0007] According to an embodiment of the third aspect of the present application, a method for indoor positioning is provided, which is optionally performed by the apparatus as described above and / or the system as described above, and which comprises: in case one or more objects in an indoor area are detected, obtaining object identities in tags of the detected objects; and sending a wireless signal containing the object identities, which is used to determine positions of the objects corresponding to the object identities. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 A schematic diagram of a system for indoor positioning according to an embodiment of the present application is shown.

[0009] Figure 2 A schematic block diagram of the system in Figure 1 is shown.

[0010] Figure 3 An exemplary positioning process according to an embodiment of the present application is shown.

[0011] Figure 4 A flowchart of a method for indoor positioning according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0012] It is noted that existing indoor positioning schemes usually require a sensor for real-time positioning for each indoor object, and the sensor for real-time positioning is usually expensive. Thus, in case there are a large number of objects in an indoor area, a large number of expensive sensors are required. The inventors of the present application propose a scheme of forming a mobile detection device by means of a fusion sensor, which can determine positions of all objects that are very close in position by one detection and calculation without requiring an expensive sensor for each object. The positioning accuracy can reach centimeter level, and the positioning speed can be almost real-time, which can meet the requirements of many indoor positioning scenarios.

[0013] Before introducing the specific embodiments of the present application, some terms appearing in the present application are explained.

[0014] In the present application, "indoor" or "indoor area" can be understood as a partially or almost completely enclosed indoor scene, such as a building or a public area in a building. For example, an indoor area can include an office, a parking lot, a conference center, a warehouse, a classroom, a theater, a supermarket, a shopping center, a sports arena, an airport waiting hall, a library, etc.

[0015] In the present application, an "object" can be understood as an object located in an indoor area, including stationary objects and mobile objects. It can be understood that a stationary object is, for example, an article or an item, but the position of the stationary object does not necessarily remain unchanged all the time, for example, the article or the item can be transferred to a different position.

[0016] In the present application, the "position of an object" or the "position of a device" can be understood as the position of the object or the device at a certain time. The "position" can take different forms. For example, the position in the embodiments of the present application can be in a local coordinate system using a local position, in a global coordinate system using a global position, in a Cartesian coordinate system using x, y and z position points, in a polar coordinate system, in a spherical coordinate system, etc.

[0017] A factory or a production workshop can be an application scenario of the embodiments of the present application. In this application scenario, the objects can include people (for example, operators), articles or items (for example, parts and boxes containing parts), machines (for example, machining equipment) and tools (for example, power tools).

[0018] The specific embodiments of the present application are described below with reference to the accompanying drawings.

[0019] Figure 1 A system 100 for indoor positioning according to an embodiment of the present application is schematically shown, which mainly includes a device 10, a control unit 20 and a digital map 30. The system 100 can also include a plurality of tags (for example, TAG1-TAG6).

[0020] Each of the plurality of tags is arranged on an object in an indoor area A. Referring to Figure 1 , the tags TAG1-TAG6 are arranged on one of the objects 1-6 respectively. The tags can be attached (for example, pasted, fixed by means of a strap, a rivet, etc.) to the surface of an article object, or embedded in the interior of an article object. The tags can also be arranged in a wearable device of a person object.

[0021] The tag has tag information. The tag information at least contains an object identifier, which is used to uniquely identify the object on which the tag is arranged. The object identifier can take various implementation forms, for example, letters, numbers, symbols or any combination thereof. The tag information can also contain additional information, for example, basic information of the object on which it is arranged. The tag can take various implementation forms, for example, a radio frequency identification tag (RFID tag), a near field communication tag (NFC tag), a two-dimensional code tag, a smart code tag.

[0022] The device 10 is configured to detect an object in the indoor area A while moving in the indoor area A. The device 10 is configured to be able to detect an object when it moves close (very close) to the object, and to read an object identification in a tag of the detected object. Then, the device 10 transmits a wireless signal containing the object identification to the control unit 20.

[0023] In one embodiment, the wireless signal can be a wireless radio frequency signal, such as a wireless local area network (WLAN) signal, a Bluetooth signal, an ultra-wideband (UWB) signal, or a Zigbee signal.

[0024] The control unit 20 is in wireless communication connection with the device 10 and receives the wireless signal from the device 10. The control unit 20 calculates the position of the device 10 based on the received wireless signal, and associates the position with the position of the object to which the object identification corresponds. In other words, the position of the device 10 is considered to be the position of the detected object at the same time as the position of the device 10 is determined, i.e. the position of the device 10 is considered to be substantially the same as the position of the detected object because the device 10 is able to detect an object only when it moves very close to the object.

[0025] The control unit 20 can be arranged in a server computer. The server computer can be arranged in or near the indoor area A (e.g. the server computer is an edge server in or near the indoor area A), or it can be arranged remotely from the indoor area A (e.g. the server computer is a remote server or a cloud server).

[0026] The control unit 20 can be implemented in hardware or software, or a combination of software and hardware. For a hardware implementation, the processing units can be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, or a combination thereof. For a software implementation, the processing units can be implemented with microcode, program code, or code segments. They can also be stored in a machine readable medium, such as a storage component.

[0027] The digital map (MAP) 30 contains map data about the indoor area A, in particular map data about the positions of the objects in the indoor area A. The digital map 30 can be stored in the control unit 20. The digital map 30 can also be stored in a database 31 external to the control unit 20, and the database 31 is able to interact information with the control unit 20.

[0028] The control unit 20 generates a corresponding time stamp after receiving each wireless signal, i.e. the time at which the wireless signal for calculating the position is received. The control unit 20 sends the object identification, the calculated object position and the corresponding time stamp to the digital map 30 in order to update this information in the digital map 30. In this way, by observing the digital map 30, it is possible to intuitively know the positions of the objects in the indoor area A and the updating of the positions of the objects.

[0029] Figure 2 An implementation of the above-described system 100 is schematically shown. As shown, the device 10 for indoor positioning mainly comprises a mobile device 11, a first sensor 12 and a second sensor 13. The mobile device 11 moves in the indoor area A. The first sensor 12 and the second sensor 13 are electrically connected and both are arranged on the mobile device 11. Thus, the first sensor 12 and the second sensor 13 move in the indoor area A along with the movement of the mobile device 11. Figure 2

[0030] The mobile device 11 can be implemented as any device suitable for moving in the indoor area A. For example, the mobile device 11 can be implemented as a mobile robot, a forklift, an elevator, a transport trolley or a conveyor belt. The mobile device 11 can move at a predetermined speed and along a predetermined route. For example, a transport trolley in a factory carries goods at a predetermined speed and along a predetermined route. It can be understood that the present application does not limit the moving speed and the running route of the mobile device 11.

[0031] The first sensor 12 is used to read the object identification in the tag of an object when approaching the object in the indoor area A and establishing a communication connection with the object.

[0032] The first sensor 12 has a detection distance, i.e. can detect the distance to an object. Approaching an object and establishing a communication connection with the object can be understood as that the distance between the first sensor 12 and the object is less than the detection distance. The detection distance of the first sensor 12 is adjustable, i.e. can be set as needed.

[0033] With the movement of the mobile device 11, the distance between the first sensor 12 and an object can be less than the detection distance, or the distances between the first sensor 12 and multiple objects can all be less than the detection distance, i.e. the first sensor 12 can detect all the objects within its detection distance at this time and read the object identifications of these objects. In other words, the number of objects detected by the first sensor 12 at one time (i.e. the number of object identifications read) depends on how many objects the first sensor 12 is within the detection distance when moving to a certain position.

[0034] ​The second sensor 13 can be communicatively connected with the first sensor 12 via a communication link (e.g., RS485 / 232 serial communication interface). The second sensor 13 sends wireless signals to the control unit 20 at a predetermined frequency. For example, the second sensor 13 sends pulse signals at the level of nanoseconds. The wireless signals emitted by the second sensor 13 can be transmitted to the control unit 20 via a base station or a gateway. The second sensor 13 always listens whether the first sensor 12 detects information. When the first sensor 12 detects an object and reads the object identification (at this time, it is considered that the first sensor detects information), the second sensor 13 acquires the object identification from the first sensor 12, and prepares to send the object identification to the control unit 20 together with the wireless signals at the next time of sending the wireless signals (e.g., during the next time of sending the pulse).

[0035] The first sensor 12 can be implemented as one of the following: a radio frequency identification sensor (RFID sensor), a near field communication sensor (NFC sensor), a two-dimensional code sensor, or a smart code sensor.

[0036] The second sensor 13 can be implemented as one of the following: an ultra-wideband sensor (UWB sensor), a camera, a Wifi sensor, or a Bluetooth sensor.

[0037] The first sensor 12 and the second sensor 13 can be implemented as separate sensors, or can be integrated together in a smart device (e.g., a smart phone). The first sensor 12 can also be integrated with the second sensor 13 as an integrated fusion sensor, i.e., a fusion sensor having the functions of the first sensor 12 and the second sensor 13.

[0038] It can be understood that, regardless of the communication link by which the first sensor 12 and the second sensor 13 are connected, the two are arranged very close in position (physical position) so as to be considered as having the same or approximately the same position.

[0039] In one embodiment, the detection and sending of signals are implemented in a manner of fusion of RFID and UWB. That is, the first sensor 12 is implemented by using an RFID reader, the second sensor 13 is implemented by using a UWB tag, and the RFID reader is communicatively connected with the UWB tag via a communication link.

[0040] In addition, the positioning accuracy and / or the position update frequency of the system 100 according to the embodiments of the present application can be adjusted.

[0041] In order to adjust the positioning accuracy based on the system 100, at least one of the following can be used to implement:

[0042] (1) Adjusting the detection distance of the first sensor 12, i.e., the distance at which the first sensor 12 can detect an object. For example, the original detection distance of the first sensor 12 is 50 cm, i.e., the first sensor 12 can detect an object when the relative distance between the first sensor 12 and the object is less than 50 cm, and now the detection distance is adjusted to 20 cm, i.e., the first sensor 12 can detect an object only when the relative distance between the first sensor 12 and the object is less than 20 cm. In this way, the positioning accuracy of the system 100 can be improved by reducing the detection distance of the first sensor 12.

[0043] (2) Adjusting the configuration scheme of the device associated with the second sensor 13. For example, the device associated with the second sensor 13 can include a base station, and the wireless signal emitted from the second sensor 13 is transmitted to the control unit 20 through the base station. By optimizing the arrangement of the base station and / or increasing the number of base stations, the positioning accuracy based on wireless signals can be improved, thereby improving the positioning accuracy of the system 100.

[0044] (3) Optimizing the algorithm for the control unit 20 to calculate the position based on wireless signals. For example, the control unit 20 can train a machine learning model by taking the parameters based on wireless signals (e.g., signal strength, relative distance to the base station, time to reach the base station, etc.) and the positions of pre-determined signal emitters as samples, and implement the positioning based on wireless signals by means of the trained machine learning model. In this way, by continuously training and optimizing the model, the positioning accuracy of the system 100 can be improved.

[0045] To adjust the frequency of updating the position based on the system 100, at least one of the following can be used:

[0046] (1) Adjusting the first frequency f1 at which the first sensor 12 detects an object.

[0047] (2) Adjusting the second frequency f2 at which the second sensor 13 transmits a wireless signal.

[0048] The frequency at which the system 100 updates the position depends on the smaller frequency of the above-mentioned first frequency f1 and second frequency f2, i.e., the frequency at which the system 100 updates the position is min(f1, f2).

[0049] Furthermore, when an object is carried on and detected by the moving device 11 (e.g., the object is placed on a transport trolley that serves as the moving device 11), the size of the device 10 (e.g., the moving trolley) can be determined by using the detection distance of the first sensor 12 and the calculated position of the device 10. For example, a circle is obtained with the calculated position as the center and the detection distance as the radius; the area of ​​this circle can be considered the size of the device 10. It is understood that the size of the device 10 can be equivalent to the size of the moving device 11 because the sensors (first and second sensors) are mounted on the moving device 11 and the size of the sensors is much smaller than that of the moving device.

[0050] Since device 10 moves within indoor area A as a mobile device, it is necessary to estimate its size and implement collision avoidance. This method allows us to determine the size of device 10 and define it as the potential collision range within indoor area A, thus facilitating collision avoidance.

[0051] Figure 3 An exemplary positioning process 300 according to a feasible embodiment of the present invention is shown. This positioning process 300 can be implemented by means of the system 100 described above.

[0052] like Figure 3 As shown, in box 302, device 10 moves within indoor area A. As device 10 moves, when first sensor 12 detects one or more objects (i.e., first sensor 12 approaches one or more objects and establishes a communication connection with the tags of these objects), first sensor 12 reads the object identifiers of these objects. The following explanation uses the detection of three objects (i.e., objects 1-3) as an example. That is, first sensor 12 reads the tag information of tags TAG1-TAG3 of objects 1-3 and obtains the object identifiers ID1-ID3 of objects 1-3.

[0053] In one embodiment, the tags TAG1-TAG3 can be implemented as RFID tags, and the first sensor 12 can be implemented as an RFID reader.

[0054] In this example, tags TAG1-TAG3 can be implemented as active RFID tags. When tags TAG1-TAG3 are implemented as active RFID tags, the active RFID tag includes an internal power source, such as a battery. Because the active RFID tag uses an internal power source, it can be continuously powered and can continuously, or at predetermined time intervals, or in response to a request from an RFID reader, transmit tag information (e.g., object identifiers ID1-ID3).

[0055] In this embodiment, the tags TAG1-TAG3 can be implemented as passive RFID tags. In case the tags TAG1-TAG3 are implemented as passive RFID tags, the RFID tags are powered by the RF power transmitted by the RFID reader. Upon receiving the RF power from the RFID reader, the passive RFID tags transmit the information stored in the tags (e.g. the object identities ID1-ID3) to the RFID reader. This transmission can be referred to as backscattering. By detecting the backscattered signal, the tag information can be identified by the RFID reader.

[0056] It can be appreciated that the RFID reader can be powered by an external power source or by an internal power source (e.g. a battery).

[0057] In block 304, the second sensor 13 acquires the detected object identities ID1-ID3 from the first sensor 12 in response to the first sensor 12 detecting the signal (i.e. reading the object identities ID1-ID3).

[0058] In block 306, the second sensor 13 includes the detected object identities ID1-ID3 into a wireless signal and transmits the wireless signal including the object identities ID1-ID3 to the control unit 20.

[0059] In one embodiment, the second sensor 13 is implemented as a UWB tag, which transmits data to the control unit 20 using nanosecond-level pulsed signals. When the second sensor 13 listens that the first sensor 12 has detected a signal (an object identity), it acquires the object identity from the first sensor 12 and prepares to transmit a wireless signal including the object identity at the next opportunity (e.g. at the next transmitted pulse)

[0060] It can be appreciated that the second sensor 13 employs high frequency (e.g. pulsed communication with repetition period in the nanosecond level) wireless communication to interact data with the control unit 20, whereby the second sensor 13 can be considered as a device that enables real-time positioning.

[0061] In block 308, the control unit 20 calculates the position of the device 10 based on the received wireless signal. The control unit 20 can employ a variety of algorithms based on the wireless signal to calculate the position of the device 10, such as time difference of arrival (TODA), time of arrival (TOA), angle of arrival (AOA), received signal indication strength (RSSI), etc. The control unit 20 can also employ models based on these algorithms to calculate the position of the device 10.

[0062] In block 310, the control unit 20 associates the calculated position of the device 10 with the position of the object to which the object identification contained in the wireless signal corresponds. That is, the position of the device 10 is assigned to the position of the detected object, since the device 10 is able to read the object identification of an object only if it is in close proximity to the object, i.e. the position of the device 10 is considered to be identical to the position of the object.

[0063] For example, in the case that the first sensor 12 detects the objects 1-3 and the second sensor 13 sends a wireless signal containing the object identifications ID1-ID3, the control unit 20 assigns the calculated position of the device 10 to the position of the objects 1-3 to which the object identifications ID1-ID3 correspond.

[0064] In block 312, the calculated object position and the corresponding time stamp are updated in the digital map 30. In one embodiment, the control unit 20 generates the time stamp upon receipt of the wireless signal. In other words, the object corresponding to the object identification contained in the wireless signal was at the calculated position at the time indicated by the time stamp.

[0065] In addition, information of all objects in the indoor area A, e.g. the object identification of each object and the related information of each object (e.g. basic information of the object, maintenance information, usage information, etc.) can be stored in an association server (not shown) of the system 100. After the control unit 20 determines the position of the detected object, the position and the corresponding time stamp can be updated in the association server.

[0066] The present application also provides a method for indoor positioning. Figure 4 A flow chart of a method 400 for indoor positioning according to an embodiment of the present application is shown. Alternatively, the method 400 can be implemented by the device 10 described above, and the method 400 can also be implemented by the system 100 described above. Therefore, the above related description is equally applicable here.

[0067] Referring to Figure 4 In step S410, upon detecting one or more objects in the indoor area, the object identification in the tag of each detected object is acquired.

[0068] In step S420, a wireless signal containing the object identification is sent, the wireless signal being used to determine the position of the object to which the object identification corresponds.

[0069] While some embodiments have been described above, it is also contemplated to be within the scope of the application to employ embodiments otherwise than those specifically described. The appended claims do not limit the scope of the application, which is limited only by the following claims.

Claims

1. A device for indoor positioning, wherein the indoor area contains a plurality of objects, each object having a tag storing at least an object identifier of the object to which it is set, the device comprising: A mobile device configured to move within the indoor area; A first sensor, disposed on the mobile device, is used to establish a communication connection with the object's tag and read the object's identifier when the object approaches; as well as The second sensor, electrically connected to the first sensor and disposed on the mobile device, is used to acquire the object identifier in response to the first sensor reading the object identifier, and to send a wireless signal containing the object identifier to the control unit located in the server computer, so that the control unit can determine the location of the device and the location of the object corresponding to the object identifier based on the wireless signal; In this configuration, the first and second sensors are arranged physically close to each other so that their positions are considered to be the same or approximately the same. The detection distance of the first sensor is adjustable, and the accuracy of the indoor positioning is adjusted by adjusting the detection distance. In the event that an object located on the mobile device is detected, the size of the device is determined based on the detection distance of the first sensor and the position of the device, and collision avoidance is performed in the indoor area based on the determined size.

2. The device as claimed in claim 1, wherein, The first frequency at which the first sensor detects the object is adjustable; and / or the second frequency at which the second sensor transmits the wireless signal is adjustable; and, The update frequency of the device's position and the object's position is determined by the smaller of a first frequency at which the first sensor detects the object and a second frequency at which the second sensor transmits wireless signals.

3. The device as claimed in claim 1, wherein, The mobile device is one of the following: a transport vehicle, a transmission mechanism, a forklift, an elevator, or a mobile robot.

4. The device as claimed in claim 1, wherein, The first sensor is one of the following: RFID sensor, NFC sensor, QR code sensor, smart code sensor; and The second sensor is one of the following: UWB sensor, camera, Wi-Fi sensor, Bluetooth sensor.

5. The device as claimed in claim 1, wherein, The first sensor is an RFID reader, the second sensor is a UWB tag, and the RFID reader and the UWB tag are connected via a communication link.

6. A system for indoor positioning, comprising: The device as described in any one of claims 1-5 is used to detect objects in an indoor area, read the object identifier of the detected objects, and transmit a wireless signal containing the object identifier. as well as The control unit is wirelessly connected to the device and receives the wireless signal. Based on the wireless signal, it calculates the location of the device and associates the location with the location of the object corresponding to the object identifier.

7. The indoor positioning system as described in claim 6, wherein, The system also includes a digital map, and the control unit sends the calculated location and corresponding timestamp to the digital map so that the location and corresponding timestamp can be updated in the digital map.

8. An indoor positioning method performed by an indoor positioning system, The indoor area contains multiple objects, and each object is equipped with a label that stores at least the object identifier of the object to which it is set; The indoor positioning system includes a device for indoor positioning and a control unit communicatively connected to the device, the device comprising: The mobile device that moves within the indoor area, and the first and second sensors mounted on the mobile device, wherein the first and second sensors are arranged physically close to each other such that their positions are considered to be the same or substantially the same. The method includes: The first sensor establishes a communication connection with the object's tag and reads the object's identifier when it approaches the object; and In response to the first sensor reading an object identifier, the second sensor acquires the object identifier and sends a wireless signal containing the object identifier to the control unit, so that the control unit can determine the location of the device and the location of the object corresponding to the object identifier based on the wireless signal; The method further includes: The accuracy of the indoor positioning is adjusted by adjusting the detection distance of the first sensor; as well as When an object located on the mobile device is detected, the size of the device is determined based on the detection distance of the first sensor and the position of the device, and collision avoidance is performed in the indoor area based on the determined size.

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