Object positioning method and device based on RFID technology, and storage medium

Abstract

The invention relates to an object positioning method and device based on the RFID technology and a storage medium, and the method comprises the steps: obtaining the measurement data of all positioning tags, and enabling the measurement positions to comprise the angle, the distance and the signal intensity; obtaining a first position of each positioning label based on the measurement data of all the positioning labels, and forming a target point set by the first positions of all the positioning labels; all the auxiliary labels are partitioned according to positions, and an auxiliary point set corresponding to each partition is determined based on measurement data of all the auxiliary labels in each partition; respectively calculating the Hausdorff distance between the target point set and each auxiliary point set, and selecting the auxiliary point set with the minimum Hausdorff distance with the target point set as a target auxiliary point set; and determining the position of the object based on the measurement data of all the auxiliary labels in the target auxiliary point set and the measurement data of the positioning label. Compared with the prior art, the method has the advantages of high anti-interference capability, low requirement on computing power of equipment and the like.

Description

Technical Field

[0001] The present invention relates to the field of RFID positioning technology, and in particular to an object positioning method, device and storage medium based on RFID technology. Background Art

[0002] RFID technology has been widely used. Although it has many advantages, such as contactless identification, fast reading, high communication efficiency, etc., it also has some defects. For example, in open warehouse management, multipath effect will be generated due to occlusion. At this time, due to the existence of multipath effect, the distance between the RFID antenna and the tag obtained by itself will be too large, thereby affecting the positioning accuracy.

[0003] In the prior art, in order to solve the influence of multipath, all images received by RFID are generally merged to achieve multipath merging. However, this method has high requirements on the overall computing power, which will lead to high hardware costs for the entire positioning system. Summary of the invention

[0004] The purpose of the present invention is to provide an object positioning method, device and storage medium based on RFID technology.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] An object positioning method based on RFID technology, wherein the object is located in a layer of a shelf, the shelf comprises multiple layers, an RFID receiving antenna is arranged on the top of each layer, and multiple auxiliary tags are arranged on the inner wall of each layer, and multiple positioning tags are arranged on the object;

[0007] The method comprises:

[0008] Obtaining measurement data of all positioning tags, wherein the measurement position includes angle, distance and signal strength;

[0009] Based on the measurement data of all the positioning tags, the first position of each positioning tag is obtained, and the first position of each positioning tag constitutes a target point set;

[0010] Partition all auxiliary tags according to their positions, and determine auxiliary point sets corresponding to each partition based on the measurement data of all auxiliary tags in each partition;

[0011] Calculate the Hausdorff distances of the target point set and each auxiliary point set respectively, and select the auxiliary point set with the smallest Hausdorff distance to the target point set as the target auxiliary point set;

[0012] The object position is determined based on the measurement data of all auxiliary tags in the target auxiliary point set combined with the measurement data of the positioning tag.

[0013] The auxiliary labels of any two partitions have no overlap.

[0014] The auxiliary labels of the two adjacent partitions overlap.

[0015] The positioning label and the auxiliary label have the same model and specification.

[0016] Auxiliary labels are arranged on each surface and edge of the inner wall of each layer.

[0017] The obtaining the first position of each positioning tag based on the measurement data of all positioning tags includes:

[0018] The first position of each positioning tag is generated according to the angle and distance in each measurement data of each positioning tag in combination with the position of the RFID antenna.

[0019] The method of determining the position of the object based on the measurement data of all auxiliary tags in the target auxiliary point set combined with the measurement data of the positioning tag includes:

[0020] Obtain the measurement data of all auxiliary tags in the target auxiliary point set, and compare them with the pre-configured reference value of each auxiliary tag. If the error between the measurement data and the reference value exceeds the pre-configured threshold, the auxiliary tag is removed to complete the simplification of the target auxiliary point set.

[0021] The target point set is corrected based on the simplified target auxiliary point set to determine the position of the object.

[0022] The method of correcting the target point set based on the simplified target auxiliary point set to determine the position of the object includes:

[0023] Calculate the distance between each data point in the simplified target auxiliary point set and each positioning label in the target point set;

[0024] For each data point in the simplified target auxiliary point set, determine the positioning label closest to it;

[0025] The position of the object is determined based on the positioning label closest to each data point in the streamlined target auxiliary point set and the position of each auxiliary label.

[0026] An object positioning device based on RFID technology comprises a memory, a processor, and a program stored in the memory. When the processor executes the program, the above method is implemented.

[0027] A storage medium stores a program, which implements the above method when executed.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. By setting more auxiliary tags and positioning tags, the partition in which the object is located is determined by combining the partitioning and Hausdorff distance matching methods, and the measurement data of the auxiliary tags and positioning tags are used for accurate correction, so that there is no need to merge the virtual image and the main body of the positioning tag. While also improving the anti-orbit capability, it greatly reduces the complexity of the algorithm design and the computing power requirements of the equipment.

[0030] 2. The auxiliary labels of any two partitions do not overlap, which can reduce the number of partitions and improve the positioning rate.

[0031] 3. Any two adjacent partitions overlap, thus avoiding the problem of low positioning accuracy when the object is located at the junction of two adjacent partitions.

[0032] 4. Auxiliary labels are simplified based on their reference values, so as to ensure that all auxiliary labels involved in the subsequent precise correction are the real body rather than virtual images, thereby further improving the accuracy.

[0033] 5. Based on the positioning label closest to each data point in the streamlined target auxiliary point set, combined with the position of each auxiliary label, the position of the object is determined, thereby eliminating the interference of virtual images and achieving accurate positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the main process steps of the method of the present invention;

[0035] Figure 2 A schematic diagram of label settings of the present invention;

[0036] Figure 3 This is a schematic diagram of distance calculation;

[0037] Figure 4 This is a schematic diagram of relative position matching. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0039] The object positioning method based on RFID technology, the object is located in a layer of the shelf, the shelf includes multiple layers, and the top of each layer is provided with an RFID receiving antenna, and Figures 2 to 4As shown, a plurality of auxiliary tags are arranged on the inner wall of each layer, and a plurality of positioning tags are provided on the object. For the auxiliary tags, the specific positions are the front frame of the shelf, the left and right sides of the shelf, and the rear of the shelf, so as to ensure the storage position (physical storage space) of each layer. There are auxiliary tags in the front, back, left and right, that is, the items that need to be positioned are stored in the space surrounded by the auxiliary positioning tags. The location information of all auxiliary tags needs to be stored in the system database in advance. The models and specifications of the positioning tags and auxiliary tags are the same.

[0040] Specifically, when one shelf layer is too long, a single RFID antenna may not be able to receive enough direct signals from auxiliary tags, so multiple RFID antennas need to be set.

[0041] like Figure 1 As shown, the method includes:

[0042] Obtaining measurement data of all positioning tags, wherein the measurement position includes angle, distance and signal strength;

[0043] Among them, it is difficult to ensure that all RFID tags are not blocked during the placement of warehouse items. Therefore, the multipath effect generated during the wireless signal transmission has a great impact on the traditional RFID positioning algorithm. Therefore, the measurement data of the positioning tag obtained must include the main body and the virtual image.

[0044] The first position of each positioning tag is obtained based on the measurement data of all positioning tags, and the first position of each positioning tag constitutes a target point set, including:

[0045] The first position of each positioning tag is generated according to the angle and distance in each measurement data of each positioning tag in combination with the position of the RFID antenna.

[0046] For an entity positioning tag, considering multipath, it has multiple virtual images. Therefore, for an entity positioning tag, it has multiple first positions. These first positions constitute a target point set. Therefore, the number of elements in the target point set is greater than the number of positioning tags. In addition, when there are multiple RFID antennas, you can choose to first screen out an RFID antenna based on distance and signal strength, and then perform subsequent processing based on this RFID antenna. Alternatively, you can process each RFID antenna, and then finally integrate the positioning results of all RFID antennas. The integration method can be to find the average position. Specifically, in a certain embodiment, if there is an RFID antenna, in the measurement data of the positioning tag it receives, the average of the three values ​​with the largest signal strength exceeds the measurement antennas of all other RFIDs, and the average of the three values ​​with the closest distance is less than that of all other RFID antennas, then the measurement data of this RFID antenna is used for subsequent calculations.

[0047] Partition all auxiliary tags according to their positions, and determine auxiliary point sets corresponding to each partition based on the measurement data of all auxiliary tags in each partition;

[0048] In some embodiments, the auxiliary tags of any two partitions do not overlap, so that the number of partitions can be reduced and the positioning rate can be improved.

[0049] Of course, in some other embodiments, the auxiliary tags of two adjacent partitions overlap, so as to avoid the problem of low positioning accuracy when the object is located at the junction of two adjacent partitions. For example, in a certain embodiment, a 50% overlap ratio can be used.

[0050] Calculate the Hausdorff distances of the target point set and each auxiliary point set respectively, and select the auxiliary point set with the smallest Hausdorff distance to the target point set as the target auxiliary point set;

[0051] Compared with directly calculating the shortest distance, the Hausdorff distance can reflect the overall posture and positional relationship of the two point sets, thereby eliminating the interference of multipath to a certain extent and better reflecting in which partition the object is actually located.

[0052] The object position is determined based on the measurement data of all auxiliary tags in the target auxiliary point set combined with the measurement data of the positioning tag, including:

[0053] Obtain the measurement data of all auxiliary tags in the target auxiliary point set, and compare them with the pre-configured reference value of each auxiliary tag. If the error between the measurement data and the reference value exceeds the pre-configured threshold, the auxiliary tag is removed to complete the simplification of the target auxiliary point set.

[0054] The target point set is corrected based on the simplified target auxiliary point set to determine the position of the object, including:

[0055] Calculate the distance between each data point in the simplified target auxiliary point set and each positioning label in the target point set;

[0056] For each data point in the simplified target auxiliary point set, determine the positioning label closest to it;

[0057] The position of the object is determined based on the positioning label closest to each data point in the streamlined target auxiliary point set and the position of each auxiliary label.

[0058] Through the above means, virtual image interference can be eliminated and precise positioning can be achieved.

[0059] This application uses auxiliary tags to achieve relative position calibration and overcome the impact of multipath effect on positioning accuracy. When the number of tag readers remains unchanged, the availability of the warehouse management system is greatly improved. The absolute position of the materials is determined by calculation by using the unchanged relative distance between the positions of multiple positioning tags and auxiliary tags and the unchanged coordinates of the auxiliary positioning tags in the database.

[0060] The present invention calculates the distance between two tag position sets based on the Hausdorff distance instead of using the shortest distance method of RFID, thereby effectively overcoming the multipath effect and improving the positioning accuracy.

[0061] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

Claims

1. An object positioning method based on RFID technology, wherein the object is located in a layer of a shelf, the shelf comprises multiple layers, an RFID receiving antenna is arranged on the top of each layer, and multiple auxiliary tags are arranged on the inner wall of each layer, and multiple positioning tags are arranged on the object; It is characterized in that The method comprises: Obtaining measurement data of all positioning tags, wherein the measurement position includes angle, distance and signal strength; Based on the measurement data of all the positioning tags, the first position of each positioning tag is obtained, and the first position of each positioning tag constitutes a target point set; Partition all auxiliary tags according to their positions, and determine auxiliary point sets corresponding to each partition based on the measurement data of all auxiliary tags in each partition; Calculate the Hausdorff distances of the target point set and each auxiliary point set respectively, and select the auxiliary point set with the smallest Hausdorff distance to the target point set as the target auxiliary point set; The object position is determined based on the measurement data of all auxiliary tags in the target auxiliary point set combined with the measurement data of the positioning tag.

2. The object positioning method based on RFID technology according to claim 1, characterized in that: The auxiliary labels of any two partitions have no overlap.

3. The object positioning method based on RFID technology according to claim 1, characterized in that: The auxiliary labels of the two adjacent partitions overlap.

4. The object positioning method based on RFID technology according to claim 1, characterized in that: The positioning label and the auxiliary label have the same model and specification.

5. The object positioning method based on RFID technology according to claim 1, characterized in that: Auxiliary labels are arranged on each surface and edge of the inner wall of each layer.

6. The object positioning method based on RFID technology according to claim 1, characterized in that: The obtaining the first position of each positioning tag based on the measurement data of all positioning tags includes: The first position of each positioning tag is generated according to the angle and distance in each measurement data of each positioning tag in combination with the position of the RFID antenna.

7. The object positioning method based on RFID technology according to claim 1, characterized in that: The method of determining the position of the object based on the measurement data of all auxiliary tags in the target auxiliary point set combined with the measurement data of the positioning tag includes: Obtain the measurement data of all auxiliary tags in the target auxiliary point set, and compare them with the pre-configured reference value of each auxiliary tag. If the error between the measurement data and the reference value exceeds the pre-configured threshold, the auxiliary tag is removed to complete the simplification of the target auxiliary point set. The target point set is corrected based on the simplified target auxiliary point set to determine the position of the object.

8. The object positioning method based on RFID technology according to claim 7, characterized in that: The method of correcting the target point set based on the simplified target auxiliary point set to determine the position of the object includes: Calculate the distance between each data point in the simplified target auxiliary point set and each positioning label in the target point set; For each data point in the simplified target auxiliary point set, determine the positioning label closest to it; The position of the object is determined based on the positioning label closest to each data point in the streamlined target auxiliary point set and the position of each auxiliary label.

9. An object positioning device based on RFID technology, comprising a memory, a processor, and a program stored in the memory, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 8 is implemented.

10. A storage medium having a program stored thereon, characterized in that: When the program is executed, the method according to any one of claims 1 to 8 is implemented.

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