A method and system for dynamic inventory of PETG film rolls in a warehouse based on the Internet of Things

Abstract

The application relates to the technical field of warehouse logistics management, and discloses a PETG film roll in-store dynamic inventory method and system based on the Internet of Things, which comprises the following steps: obtaining Internet of Things sensing data and warehouse business data of the PETG film roll and establishing a film roll state record; determining a stable position range based on historical position sensing information and positioning error parameters; determining effective deviation when position sensing information of consecutive multiple collection cycles is located outside the stable position range; matching a position change track corresponding to the effective deviation with flow operation information to determine a dynamic inventory object; controlling a target Internet of Things collection device to perform secondary verification on the dynamic inventory object to obtain an inventory confirmation result; updating the film roll state record according to the inventory confirmation result, and updating the stable position range only by using verified normal position sensing information. The application can effectively distinguish between positioning fluctuation and real displacement, reduce invalid inventory tasks, and improve the accuracy and reliability of inventory management.

Description

Technical Field

[0001] This invention relates to the field of warehousing and logistics management technology, and more specifically, to a method and system for dynamic inventory counting of PETG film rolls in storage based on the Internet of Things. Background Technology

[0002] With the rapid development of information technology and the Internet of Things (IoT) in warehouse management, modern warehouses commonly use electronic tags such as RFID tags and location tags for digital management of inventory. By deploying fixed reading and writing devices, mobile inventory terminals, or positioning base stations, the system can acquire the identification information and spatial location information of materials in real time or periodically. The warehouse management system synchronously records the flow operations of materials, including warehousing, transfer, and outbound operations, based on the collected data. Managers monitor the accuracy of material quantity and the compliance of storage location by comparing the on-site data with the system's theoretical inventory records, thereby achieving visualized and refined inventory management. PETG film products are typically packaged, stored, temporarily stored, transferred, and outbound in roll form. Different rolls may only differ in production batch, thickness, width, or surface treatment, resulting in limited visual identification. During warehousing, rolls are usually stored on shelves, pallets, or in centralized stacking. Packaging materials, metal shelves, and adjacent rolls may obstruct, reflect, or cause multipath interference to wireless identification and positioning signals, leading to short-term fluctuations in the location perception information obtained by the same roll when it is stationary. When PETG film rolls are moved but the business records are not written in time, or when film rolls are moved without being registered, it is difficult to distinguish between location drift, normal circulation and abnormal movement by comparing the location collected in a single instance with the book location. This can easily lead to false inventory reports or incorrect inventory location records.

[0003] In continuous location-aware inventory management applications, existing technologies typically involve deploying IoT data acquisition devices to obtain location information of materials and combining this with warehousing operational data for status monitoring. Specifically, the system uses historical location data to establish a baseline, identifies material movement by comparing the current acquisition location with the baseline location, and attempts to determine the nature of the movement by combining it with circulation operation information.

[0004] However, existing technologies still have significant problems in practical applications. First, it is difficult to accurately distinguish between positioning fluctuations caused by equipment errors, normal business flow movements, and unrecorded abnormal position changes, leading to delayed or misjudged status assessments. Second, in complex field environments, existing methods often fail to effectively balance the relationship between instantaneous drift interference in positioning data and actual displacement detection. This can easily trigger invalid inventory tasks due to signal reflection or instantaneous drift, or lead to subsequent misjudgments of status due to unverified abnormal data, thus affecting the accuracy and timeliness of inventory operations. Summary of the Invention

[0005] In view of this, the present invention proposes a method and system for dynamic inventory counting of PETG film rolls in stock based on the Internet of Things, aiming to solve the technical problem of how to distinguish between location fluctuations, normal circulation and unrecorded location changes under continuous location sensing conditions, and to perform dynamic inventory counting for materials that need to be confirmed.

[0006] This invention provides a method for dynamic inventory management of PETG film rolls based on the Internet of Things, comprising: Acquire IoT sensing data and warehousing business data corresponding to PETG membrane rolls, and establish membrane roll status records based on the IoT sensing data and the warehousing business data; Based on the historical position sensing information in the membrane roll status record and the positioning error parameters of the corresponding IoT acquisition device, the stable position range of the PETG membrane roll is determined. The location sensing information currently collected is compared with the stable location range. If the location sensing information is outside the stable location range within a set number of consecutive collection cycles, it is determined that the corresponding material has deviated effectively. The effective deviation corresponding to the position change trajectory is matched with the flow operation information in the warehousing business data, and the dynamic inventory objects are determined based on the matching results; Based on the warehouse area where the dynamic inventory object is located, the target IoT data collection device is determined, and the target IoT data collection device is controlled to perform a secondary verification of the dynamic inventory object to obtain the inventory confirmation result. The membrane roll status record is updated based on the inventory confirmation results, and the stable position range is updated only based on the position sensing information that has been verified as normal after two verifications.

[0007] Furthermore, acquiring the IoT sensing data and the warehousing business data includes: Material identification information, location awareness information, collection time, and device identification are obtained by IoT collection devices set up in the warehouse area. The positioning error parameters of the corresponding IoT collection device are retrieved according to the device identification. The positioning error parameters include spatial positioning error and allowable instantaneous drift duration. The warehouse management system obtains the circulation operation information corresponding to the material identification information. The circulation operation information includes operation type, operation time, starting storage location and target storage location. The operation type includes inbound operation, transfer operation and outbound operation. The location awareness information and the circulation operation information are associated with the material identification information, and time-series alignment is performed according to the collection time and the operation time.

[0008] Furthermore, establishing the membrane roll state record includes: The membrane roll identifier is determined based on the material identification information, and a material status index is established using the membrane roll identifier. The location sensing information corresponding to the same membrane roll identifier is arranged according to the collection time to form a material location change trajectory, and the device identifier corresponding to each location sensing information is recorded in the material location change trajectory. The circulation operation information is associated with the material location change trajectory according to the operation time, and sample status markers are set for each location sensing information. The sample status markers include a pending confirmation marker, a normal confirmation marker, and an abnormal confirmation marker. The membrane roll identifier, the material location change trajectory, the circulation operation information, and the sample status mark are associated to form the membrane roll status record.

[0009] Further, determining the stable position range includes: From the material location change trajectory, the location perception information with the sample status marked as normal confirmation is selected, and the location perception information during the execution period of the warehousing operation, the transfer operation or the outbound operation is excluded to form a stable location sample set. The center position is determined based on the position sensing information of each position in the stable position sample set, and the distance between each position sensing information and the center position is determined. The sum of the maximum value of the distances and the spatial positioning error is determined as the boundary distance, and the area defined by the boundary distance with the center position as the reference is taken as the stable position range.

[0010] Furthermore, when the PETG film roll lacks the historical location-aware information required to form the stable location sample set, including: The storage location calibration area is determined based on the target storage location corresponding to the storage operation. The boundary of the storage location calibration area is extended outward by the distance corresponding to the spatial positioning error to form an initial stable location range. After the warehousing operation is completed, location sensing information is continuously collected, and location sensing information that has been verified to be normal after a second verification is marked as a normal confirmation mark. When the number of location perception information samples with normal confirmation marks reaches a set number, the stable location range is redefined by selecting the location perception information with normal confirmation marks to determine the center position and using the sum of the maximum distance and the spatial positioning error as the boundary distance.

[0011] Further, determining the valid deviation includes: Determine whether the location sensing information obtained in each acquisition cycle is within the stable location range; When the location sensing information of a collection cycle is outside the stable location range, a deviation candidate record is established, and the deviation start time and corresponding location sensing information are recorded. When subsequent location sensing information returns to the stable location range before reaching the number of consecutive acquisition cycles, the deviation candidate record is deleted; When the number of consecutive acquisition cycles in which the location sensing information is continuously outside the stable location range reaches the number of consecutive acquisition cycles, the deviation candidate record is determined as a valid deviation, and the location change trajectory corresponding to the valid deviation is formed based on the location sensing information after the deviation start time. The number of continuous acquisition cycles is determined by rounding up the ratio between the allowed instantaneous drift duration and the acquisition cycle of the IoT acquisition device.

[0012] Furthermore, when matching the effective deviation corresponding to the position change trajectory with the flow operation information, it includes: From the warehousing business data, select the transfer operation information with the same film roll identifier and whose operation time and the time difference between the deviation from the start time do not exceed the set synchronization time to form candidate transfer operation information. The set synchronization time is determined based on the maximum time synchronization error between the warehousing management system and the Internet of Things acquisition device. It is determined whether the starting storage position in the candidate flow operation information matches the stable position range, whether the target storage position matches the end position of the position change trajectory, and whether the change direction of the position change trajectory points from the starting storage position to the target storage position. When all the above judgment results are a match, the corresponding candidate circulation operation information will be determined as valid circulation operation information, and the corresponding materials will be determined as normal circulation materials. When no valid transfer operation information exists, the corresponding material will be identified as the dynamic inventory object.

[0013] Furthermore, when controlling the target IoT data acquisition device to perform secondary verification of the dynamically inventoried object, the process includes: The target storage location is determined based on the end position of the corresponding position change trajectory of the effective deviation, and the collection coverage area is limited to the target storage location and the storage locations adjacent to the target storage location. The IoT collection device whose collection coverage includes the target storage location enters the verification collection state, and the collection cycle of the target IoT collection device is switched to the verification collection cycle. The verification collection cycle is determined by completing no less than three collections within the allowed instantaneous drift duration. During the continuous verification period, material identification information and location awareness information of the dynamic inventory object are collected. When the material identification information obtained from each collection points to the same material and the location awareness information is concentrated in the same storage location, the same storage location is determined as the verification storage location. When the verification storage location is within the range of the stable locations, or when the verification storage location matches the target storage location in the valid transfer operation information, a normal inventory confirmation result is generated; when the verification storage location is outside the range of the stable locations and there is no corresponding valid transfer operation information, an abnormal inventory confirmation result is generated.

[0014] Furthermore, updating the membrane roll status record based on the inventory confirmation results includes: When the normal inventory confirmation result is obtained, the location awareness information obtained from the secondary verification is set as the normal confirmation mark, and the normal inventory confirmation result is associated with the corresponding material location change trajectory. When the normal inventory confirmation result corresponds to valid transfer operation information, and the location sensing information is continuously collected for a set number of cycles after the transfer operation is completed and remains at the target storage location, the corresponding location sensing information is added to the stable location sample set, and the stable location range is redefined. When the abnormal inventory confirmation result is obtained, the location awareness information obtained from the secondary verification is set as an abnormal confirmation mark, the abnormal location change is recorded and the material location change trajectory is updated, the current stable location range remains unchanged, and location awareness information with abnormal confirmation marks is prohibited from entering the stable location sample set.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This solution acquires IoT sensing data and warehousing business data corresponding to PETG membrane rolls and establishes membrane roll status records. Based on historical location sensing information and positioning error parameters, it determines a stable location range that accommodates equipment errors, allowing material status judgment to no longer rely on a single coordinate point but instead form a regional benchmark that can accommodate normal fluctuations. Furthermore, by comparing the currently continuously collected location sensing information with the stable location range and using a set number of consecutive collection cycles as a judgment threshold, only when the location information continuously exceeds this range is it determined to be a valid deviation, thus effectively filtering out short-term position fluctuations caused by signal reflection or instantaneous drift. Subsequently, the location change trajectory corresponding to the valid deviation is spatiotemporally matched with the flow operation information in the warehousing business data to verify whether the start, end, and direction of the location change are consistent with the recorded business operations, thereby accurately identifying dynamic inventory objects without order movement. For these objects, the system uses the target IoT acquisition device in the directional control area for secondary verification, narrowing the collection range and increasing the sampling frequency to obtain high-confidence inventory confirmation results. Ultimately, the stable location range is updated only based on location sensing information that has been verified twice and confirmed to be normal, thus avoiding the contamination of subsequent judgment criteria by abnormal data. Therefore, this invention effectively solves the technical problem of how to distinguish between location fluctuations, normal flow, and unrecorded location changes under continuous location sensing conditions, and how to perform dynamic inventory checks on materials that require confirmation. It avoids situations where invalid inventory tasks are triggered by location noise or subsequent misjudgments are caused by unverified abnormal data, thereby improving the automation level, data reliability, and management efficiency of warehouse material inventory checks.

[0016] On the other hand, the present invention provides an IoT-based dynamic inventory system for PETG film rolls, used to implement the above-mentioned IoT-based dynamic inventory method for PETG film rolls in stock, including: The data acquisition module is used to acquire material identification information and location perception information corresponding to PETG film rolls through IoT acquisition devices, acquire corresponding circulation operation information through the warehouse management system, and acquire positioning error parameters of the IoT acquisition devices. The status record establishment module is used to establish a membrane roll status record based on the material identification information, the location perception information and the circulation operation information. The membrane roll status record includes the material location change trajectory and sample status markers of the location perception information. A stable range determination module is used to determine a stable position range based on historical position sensing information with normal confirmation markers and the positioning error parameters. The deviation recognition module is used to compare the currently continuously collected position sensing information with the stable position range, and to determine a valid deviation when the position sensing information is outside the stable position range for a set number of consecutive collection cycles. The flow matching module is used to match the position change trajectory corresponding to the effective deviation with the operation time, starting storage position and target storage position in the flow operation information, and to determine the dynamic inventory object when there is no effective flow operation information; The inventory control module is used to determine the target IoT data collection device based on the warehouse area where the dynamic inventory object is located, control the target IoT data collection device to adjust the collection coverage and collection cycle, perform secondary verification on the dynamic inventory object, and obtain the inventory confirmation result. The status update module is used to update the membrane roll status record based on the inventory confirmation result, and only use the position awareness information with normal confirmation mark to update the stable position range.

[0017] It should be noted that the IoT-based dynamic inventory system for PETG film rolls of the present invention has the same beneficial effects as its method, and will not be described in detail here. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart illustrating a method for dynamic inventory management of PETG film rolls based on the Internet of Things (IoT) provided in this embodiment of the invention.

[0020] Figure 2 This is a functional framework diagram of an IoT-based dynamic inventory system for PETG film rolls, provided for an embodiment of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] In this embodiment, the inventory consists of roll-packaged PETG film products. Each PETG film roll has a unique roll identifier, which is associated with the production batch, roll specifications, and current inventory status. IoT tags are affixed to the end of the roll core, the outer packaging surface, or the pallet carrying the roll. When multiple PETG film rolls are carried on the same pallet, each roll is labeled, and the pallet is labeled. The loading relationship between the roll labels and the pallet labels is recorded in the warehouse management system. IoT data acquisition devices obtain the identification information and location awareness information from the roll labels, and the warehouse management system records the PETG film roll inbound, outbound, and in-warehouse operations.

[0024] See Figure 1 As shown, this embodiment of the invention provides a method for dynamic inventory counting of PETG film rolls in stock based on the Internet of Things, including the following steps.

[0025] S101: Acquire IoT sensing data and warehousing business data, and establish membrane roll status records.

[0026] The IoT data acquisition device acquires material identification information, location awareness information, acquisition time, and device identification of PETG film rolls according to the acquisition cycle.

[0027] Material identification information can be RFID tag code, UWB tag code, Bluetooth tag code, or other unique identifier; location awareness information can be two-dimensional coordinates, three-dimensional coordinates, or storage location area number; equipment identification is used to identify the IoT data acquisition device that generates location awareness information.

[0028] Based on the device identifier, retrieve the positioning error parameters of the corresponding IoT data acquisition device from the device configuration table. The positioning error parameters include spatial positioning error and allowable instantaneous drift duration.

[0029] Spatial positioning error can be determined during the installation or calibration phase of IoT data acquisition devices. Specifically, multiple calibration locations are set within the device's coverage area, and the deviations between the locations measured by the IoT data acquisition devices and the calibration locations are compared. The spatial positioning error is then determined based on the maximum value of the deviations or a set quantile value.

[0030] The allowable duration of momentary drift can be determined by continuously collecting the location data of stationary materials. The duration during which the location-aware information recovers on its own after briefly deviating from the normal distribution range is statistically analyzed, and the duration that covers a set proportion of short-term drift events is determined as the allowable duration of momentary drift.

[0031] Warehouse operation data is obtained from the warehouse management system and includes at least the flow operation information corresponding to the material identification information. The flow operation information includes operation type, operation time, starting storage location, and target storage location. Operation types include inbound operations, transfer operations, and outbound operations.

[0032] In this embodiment, the operation time can be represented by a time interval, which includes the operation start time and the operation completion time. When the warehouse management system records only one timestamp, this timestamp can be used as the operation start time or the operation completion time, and a corresponding operation time interval can be formed according to the business operation duration.

[0033] Using material identification information as the associated field, location awareness information and flow operation information are grouped into the same material status index. A unified time base is used for both data collection and operation times. The maximum time synchronization error between the warehouse management system and the IoT data collection devices includes the maximum time difference caused by device clock deviation, network transmission latency, and business data write latency.

[0034] The location sensing information of the same material is arranged according to the collection time to form the material location change trajectory, and then the circulation operation information is associated with the material location change trajectory according to the operation time.

[0035] The membrane roll status record includes membrane roll identification, material location change trajectory, transfer operation information, equipment identification, and sample status markers. Sample status markers include pending confirmation markers, normal confirmation markers, and abnormal confirmation markers.

[0036] Newly collected location awareness information that has not yet been verified is marked as pending confirmation; location awareness information that has been confirmed through secondary verification as belonging to normal storage or normal circulation is marked as normal confirmation; when a location change that has been confirmed through secondary verification as not supported by business records is identified, the corresponding location awareness information is marked as abnormal confirmation. When PETG film rolls are stored on metal shelves or adjacent film rolls are closely arranged, the tag signal may be affected by shelf reflection, film roll obstruction, and simultaneous response of adjacent tags. During secondary verification, the antenna or positioning base station corresponding to the target storage location can be selected to reduce the reading power of the collection equipment in non-target storage locations and continuously collect film roll identification and location awareness information. If the dynamic inventory object has a loading relationship with the pallet, the pallet label can also be verified simultaneously, and the storage location is determined based on whether the film roll label and the pallet label are located in the same storage location.

[0037] An anomaly confirmation flag indicates that the corresponding location sensing information should not be used to update the stable location range of materials, and does not mean that the location data collected by the IoT data acquisition device is necessarily wrong.

[0038] S102: Determine the stable position range of the PETG film roll.

[0039] Each time a material completes a confirmed receiving or transfer operation, it enters a new stable storage phase. A stable storage phase begins at the time the most recent confirmed receiving or transfer operation is completed and ends at the time the next circulation operation begins.

[0040] For the current stable storage phase, location awareness information with normal confirmation marks is screened from the material location change trajectory, and location awareness information collected during the period of warehousing operation, transfer operation or outbound operation is excluded, forming a current stable location sample set.

[0041] By using data from the current stable storage phase to establish a stable location sample set, it is possible to avoid using location awareness information from different storage locations before and after the relocation for the same stable location range calculation.

[0042] In a two-dimensional positioning scenario, the stable position sample set includes multiple position coordinates. The average of the x-coordinate and y-coordinate of each position coordinate is used to determine the center position. Specifically, the center position in a two-dimensional positioning scenario is determined by the following formula: , ; In the formula, m is the number of position-aware information items in the stable position sample set, (x i ,y i ) represents the location-aware information of the i-th position. , The center position is ( ). In a 3D positioning scenario, the average value of the height coordinates is also calculated in the same way.

[0043] Determine the distance between the perceived information of each location in the stable location sample set and the central location, and determine the maximum distance from it.

[0044] When the location-aware information in the stable location sample set is generated by the same IoT acquisition device, the sum of the maximum distance and the spatial positioning error of the IoT acquisition device is determined as the boundary distance.

[0045] When the location-aware information in the stable location sample set is generated by multiple IoT acquisition devices, the spatial positioning error of each IoT acquisition device is obtained, and the sum of the largest spatial positioning error and the largest distance is determined as the boundary distance. In a two-dimensional positioning scenario, the boundary distance is determined according to the following formula: ; In the formula, R is the boundary distance and ε is the spatial positioning error; when the stable position sample is generated by multiple IoT acquisition devices, ε takes the maximum value of the spatial positioning errors of each IoT acquisition device.

[0046] The stable location range is defined by the area at the center location as a reference and the boundary distance as a boundary. For the currently acquired location-aware information (x... t ,y t When the following equation is satisfied, the location sensing information is determined to be outside the stable location range: ; If the above formula is not satisfied, the location sensing information is determined to be within a stable location range.

[0047] In a two-dimensional positioning scenario, the stable position range can be a circular area; in a three-dimensional positioning scenario, the stable position range can be a spherical area.

[0048] When materials are first stored in the warehouse, and there is no historical location sensing information required to form a stable location sample set, the warehouse location calibration area is determined based on the target storage location during the storage operation. The boundary of the warehouse location calibration area is then extended outward by the distance corresponding to the spatial positioning error to form an initial stable location range.

[0049] After the warehousing operation is completed, the IoT data acquisition device continuously collects the location sensing information of the materials. Location sensing information that is confirmed to be normal after secondary verification is set as a normal confirmation mark. When the number of location sensing information with normal confirmation marks in the current stable storage phase reaches a set number, the center position and boundary distance are re-determined based on the location sensing information, and the initial stable position range is replaced with the re-determined stable position range.

[0050] The number of samples can be determined based on the positioning stability and collection cycle of the IoT data acquisition device, for example, 10 to 30.

[0051] S103: Determine the effective deviation based on continuous position sensing information.

[0052] The IoT data acquisition device continuously acquires the position sensing information of the PETG membrane roll according to the acquisition cycle, and determines whether the position sensing information obtained in each acquisition cycle is within a stable position range.

[0053] When the position sensing information obtained in a data acquisition cycle is outside the stable position range, a deviation candidate record is established. The deviation candidate record includes at least the membrane roll identifier, the deviation start time, the position sensing information, and the device identifier.

[0054] The number of continuous acquisition cycles is determined by rounding up the ratio between the allowable instantaneous drift duration and the acquisition cycle of the IoT acquisition device, specifically: ; N is the number of consecutive acquisition cycles required to confirm a valid deviation, and T is... d To allow for the duration of instantaneous drift, T s This refers to the data collection cycle of IoT data acquisition devices. This indicates rounding up to the nearest integer.

[0055] In this embodiment, the position sensing information initially located outside the stable position range is used to establish deviation candidate records and is not considered as a completed continuous acquisition cycle. After the deviation candidate records are established, the continuous acquisition cycle count is incremented once for each complete acquisition cycle in which the obtained position sensing information is still outside the stable position range.

[0056] Therefore, when the continuous sampling cycle count reaches the number of continuous sampling cycles, at least the allowable instantaneous drift time has elapsed since the deviation from the start time, thus avoiding directly equating the number of sampling points with the duration.

[0057] After the deviation candidate record is established, if the position awareness information returns to a stable position range before the continuous acquisition cycle count reaches the number of continuous acquisition cycles, it is determined that this out-of-bounds movement belongs to the allowed instantaneous drift, and the deviation candidate record is deleted.

[0058] If the location sensing information is continuously outside the stable location range and the continuous acquisition cycle count reaches the number of continuous acquisition cycles, the deviation candidate record is determined as a valid deviation, and the location sensing information obtained after the deviation start time is arranged according to the acquisition time to form the location change trajectory corresponding to the valid deviation.

[0059] For example, if the allowed instantaneous drift duration is 30 seconds and the acquisition cycle is 5 seconds, then the number of consecutive acquisition cycles is 6. The first out-of-bounds position sensing information establishes a deviation candidate record, and thereafter, an acquisition cycle is completed every 5 seconds; when 6 consecutive acquisition cycles have passed and the position sensing information is all outside the stable position range, a valid deviation is confirmed.

[0060] S104: Match the location change trajectory and circulation operation information to determine the dynamic inventory objects.

[0061] After a valid deviation occurs, the warehouse operation data is used to filter out the transfer operation information of materials with the same film roll identifier as the materials that have a valid deviation.

[0062] The deviation from the start time is compared with the operation time of each workflow operation. If the deviation from the start time is within the operation time interval, or the time difference between the deviation from the start time and the boundary of the operation time interval does not exceed the set synchronization duration, the corresponding workflow operation information is determined as candidate workflow operation information.

[0063] The synchronization duration is set based on the maximum time synchronization error between the warehouse management system and the IoT data acquisition devices. The maximum time synchronization error already includes system clock skew, data transmission delay, and business data write delay.

[0064] For candidate flow operation information, perform the following matching: Determine whether the starting storage location in the candidate transfer operation information is within the stable location range, or whether it is consistent with the storage location corresponding to the stable location range; Determine whether the target storage location in the candidate transfer operation information contains the end position of the location change trajectory, or whether it is consistent with the storage location where the end position is located; Determine whether the overall direction of change of the position change trajectory is from the starting storage location to the target storage location.

[0065] The direction of position change can be determined based on the direction vector formed by the starting and ending positions of the position change trajectory, or it can be determined based on the storage areas that the position change trajectory passes through in sequence.

[0066] When the membrane roll identifier, operation time, starting storage location, target storage location, and direction of location change all match, the candidate transfer operation information is determined as valid transfer operation information, and the corresponding material is determined as normal transfer material.

[0067] When there is no valid transfer operation information, the corresponding materials will be identified as dynamic inventory objects.

[0068] The result of the dynamic inventory object identification indicates that, at the current business data query time, no transfer operation information that can explain a valid deviation has been found. This result does not rule out the possibility that transfer operation information was supplemented during the secondary verification period due to delays in business data writing.

[0069] S105: Perform secondary verification on the objects of dynamic inventory.

[0070] The target storage location is determined based on the end position of the location change trajectory of the dynamically inventoried object, and an IoT data collection device capable of collecting information on materials in the target storage location and adjacent storage locations is selected as the target IoT data collection device.

[0071] Different implementation methods can be used to verify the collection status for different types of IoT data collection devices.

[0072] When the IoT data acquisition device is an RFID reader / writer, the antenna group corresponding to the target storage location can be enabled, the antenna in the non-target area can be disabled, or the reading / writing power can be adjusted so that the effective reading area is concentrated on the target storage location and adjacent storage locations.

[0073] When the IoT data acquisition device is a UWB positioning device, the positioning base station in the area where the target storage location is located can be selected to participate in the location calculation, thereby increasing the location reporting frequency of the target tag and limiting the location calculation area to the target storage location and adjacent storage locations.

[0074] When the IoT data acquisition device is a Bluetooth positioning device, a Bluetooth gateway within the target area can be selected to increase the scanning frequency and process only the scan data corresponding to the target storage location and adjacent storage locations.

[0075] Therefore, the limited collection coverage in this embodiment can be achieved either by adjusting the physical collection area of ​​the device or by selecting a target area collection device, antenna, or base station and limiting the location data processing area.

[0076] The control target IoT data acquisition device switches from a regular data acquisition cycle to a verification data acquisition cycle. The verification data acquisition cycle is no longer than the value obtained by dividing the allowable instantaneous drift duration by the minimum number of verification data acquisitions. The minimum number of verification data acquisitions is no less than 3.

[0077] For example, when the allowed instantaneous drift duration is 15 seconds and the minimum number of verification collections is 3, the verification collection cycle is no more than 5 seconds.

[0078] During the continuous verification period, acquire material identification information and location awareness information of the dynamically inventoried objects. If the material identification information obtained from each valid acquisition all points to the same material, and the location awareness information is all mapped to the same storage location or concentrated within the positioning error range of that storage location, then the same storage location is determined as the verification storage location.

[0079] After determining the verification storage location, the flow operation information corresponding to the dynamic inventory object up to the end of the second verification is retrieved from the warehouse management system again, and the matching is performed again according to the film roll identifier, operation time, starting storage location, target storage location and location change direction in step S104.

[0080] This re-acquisition process is used to handle situations where warehousing business data is written to the warehousing management system later than the actual movement of materials.

[0081] When the verification storage location is within the original stable location range, it indicates that the previous location out-of-bounds violation did not persist in the second verification, and a normal inventory confirmation result is generated.

[0082] When the verified storage location is outside the original stable location range, but after matching again, valid transfer operation information is obtained, and the verified storage location matches the target storage location in the valid transfer operation information, it indicates that the materials have completed normal warehousing or transfer, and a normal inventory confirmation result is generated.

[0083] When the verification storage location is outside the original stable location range, and no valid transfer operation information is found after matching again, an abnormal inventory confirmation result is generated.

[0084] If consistent material identification information cannot be obtained or the storage location cannot be determined during a continuous verification period, the dynamic inventory object status is maintained, and a supplementary inventory task is generated for confirmation by a mobile inventory terminal or manually.

[0085] S106: Update the membrane roll status record and stable position range based on the inventory confirmation results.

[0086] When the verification storage location is within the original stable location range and a normal inventory confirmation result is generated, the location awareness information obtained from the secondary verification is set as a normal confirmation marker, the normal inventory confirmation result is associated with the material location change trajectory, and the current stable location range is maintained.

[0087] Previously valid deviations that have not been verified as normal are still marked as pending confirmation and are not directly added to the stable location sample set.

[0088] When the normal inventory confirmation result corresponds to valid transfer operation information, and the verified storage location matches the target storage location in the valid transfer operation information, the original stable storage phase of the material ends at the start time of this transfer operation, and the stable location sample set of the original stable storage phase is sealed.

[0089] A new stable storage phase is established starting from the moment this transfer operation is completed. The location-aware information obtained from the secondary verification and marked with a normal confirmation flag is added to the new stable location sample set, without being mixed with the samples corresponding to the original storage location.

[0090] In the new stable storage phase, when the location-aware information is continuously collected for a set number of cycles at the target storage location, and the number of location-aware information samples with normal confirmation marks reaches the set number, the center position and boundary distance are re-determined based on the new stable location sample set, forming a new stable location range corresponding to the target storage location.

[0091] Before a new stable location range is formed, the area obtained by extending the spatial positioning error outward from the storage location calibration area corresponding to the target storage location can be used as a transitional stable location range.

[0092] When the abnormal inventory confirmation result is obtained, the location awareness information obtained from the secondary verification is set as the abnormal confirmation mark, and the deviation start time, original stable position, verification storage position and position change trajectory of the abnormal position change are recorded, while keeping the original stable position range unchanged.

[0093] Location-aware information with anomaly confirmation markers must not be included in any stable location sample set, nor will it participate in the calculation of center position and boundary distance.

[0094] By managing stable location sample sets separately according to stable storage stages, we can avoid using data from different locations before and after material relocation to calculate the same stable location range; by obtaining transfer operation information again after secondary verification, we can identify normal transfers caused by delayed writing of business records; by restricting abnormal confirmation data from entering the stable location sample set, we can prevent abnormal location status from changing the subsequent judgment benchmark.

[0095] Taking a warehouse area using UWB positioning equipment as an example, the spatial positioning error is 0.10 meters, the allowable instantaneous drift duration is 15 seconds, and the normal collection cycle is 5 seconds.

[0096] The PETG membrane roll is identified as PETG-240615-018. The warehouse management system records its specifications as a thickness of 0.50 mm and a width of 1250 mm. Its current stable storage location is location A01. The center location is determined based on 20 normally confirmed location sensing information points during the current stable storage phase. The maximum distance between the 20 location sensing information points and the center location is 0.08 meters, therefore the boundary distance is 0.18 meters.

[0097] When a location-aware information is outside the stable location range, a deviation candidate record is established. After three consecutive complete acquisition cycles (15 seconds), if the location-aware information is still outside the stable location range, a valid deviation is determined.

[0098] The location change trajectory ends at storage location B03. No matching transfer operation information was found during the initial query of the warehouse management system; therefore, this item was identified as a dynamic inventory item.

[0099] The UWB positioning base station in the area where storage location B03 is located is put into verification and data collection mode. The tag location reporting cycle is adjusted to 5 seconds, and three location sensing information are obtained continuously. All three location sensing information points to the same material located in storage location B03. Therefore, storage location B03 is determined as the verification storage location.

[0100] After the second verification, the warehouse management system is queried again. If at this time a transfer operation is obtained with the starting storage location being A01 and the target storage location being B03, and the operation time and direction of change both match the location change trajectory, then a normal inventory confirmation result is generated, the stable location sample set corresponding to storage location A01 is sealed, and a new stable location sample set is established for storage location B03.

[0101] If no matching transfer operation information is found after a second query, an abnormal inventory confirmation result is generated, the stable location range corresponding to storage location A01 remains unchanged, and the abnormal confirmation location awareness information corresponding to storage location B03 is prohibited from being used to update the stable location range.

[0102] See Figure 2 As shown, this embodiment provides an IoT-based dynamic inventory system for PETG film rolls, including a data acquisition module, a status record establishment module, a stability range determination module, a deviation identification module, a transfer matching module, an inventory control module, and a status update module.

[0103] The data acquisition module is used to acquire material identification information, location perception information, acquisition time and equipment identification through IoT acquisition devices, acquire circulation operation information through the warehouse management system, and obtain spatial positioning error and allowable instantaneous drift duration based on equipment identification.

[0104] The status record establishment module is used to establish a material status index with membrane roll identifier, form a material location change trajectory according to the collection time, associate the circulation operation information with the material location change trajectory, and set a pending confirmation mark, normal confirmation mark or abnormal confirmation mark for the location perception information.

[0105] The stable range determination module is used to filter location perception information with normal confirmation marks according to the current stable storage stage of materials, form a current stable location sample set, and determine the stable location range based on the center position, maximum distance and spatial positioning error.

[0106] The deviation identification module is used to compare continuously acquired position sensing information with a stable position range. When the position sensing information is continuously outside the stable position range for an allowable instantaneous drift duration, a valid deviation is determined.

[0107] The circulation matching module is used to filter candidate circulation operation information based on membrane roll identification and operation time, and match the starting storage location, target storage location, and direction of location change; when there is no valid circulation operation information at the current query time, the corresponding material is identified as a dynamic inventory object.

[0108] The inventory control module is used to select the target IoT collection device based on the target storage location of the dynamically inventoried object, so that the target IoT collection device enters the target area verification and collection state, and after the second verification is completed, it obtains the flow operation information again to generate normal inventory confirmation result or abnormal inventory confirmation result.

[0109] The status update module is used to update the sample status markers and material location change trajectories based on the inventory confirmation results. When a normal relocation is confirmed, the stable location sample set of the original stable storage phase is sealed, and a new stable location sample set is established for the target storage location; when an anomaly is confirmed, the original stable location range is maintained, and location awareness information with anomaly confirmation markers is prohibited from being used to update the stable location range.

[0110] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the present invention.

Claims

1. A method for dynamic inventory counting of PETG film rolls based on the Internet of Things, characterized in that, include: Obtain IoT sensing data and warehousing business data corresponding to the PETG membrane rolls in stock, and establish membrane roll status records based on the IoT sensing data and the warehousing business data; Based on the historical position sensing information in the membrane roll status record and the positioning error parameters of the corresponding IoT acquisition device, the stable position range of the PETG membrane roll is determined. The location sensing information currently collected is compared with the stable location range. If the location sensing information is outside the stable location range within a set number of consecutive collection cycles, it is determined that the corresponding material has deviated effectively. The effective deviation corresponding to the position change trajectory is matched with the flow operation information in the warehousing business data, and the dynamic inventory objects are determined based on the matching results; Based on the warehouse area where the dynamic inventory object is located, the target IoT data collection device is determined, and the target IoT data collection device is controlled to perform a secondary verification of the dynamic inventory object to obtain the inventory confirmation result. The membrane roll status record is updated based on the inventory confirmation results, and the stable position range is updated only based on the position sensing information that has been verified as normal after two verifications.

2. The method for dynamic inventory management of PETG film rolls based on the Internet of Things according to claim 1, characterized in that, When acquiring the IoT sensing data and the warehousing business data, the following are included: Material identification information, location awareness information, collection time, and device identification are obtained by IoT collection devices set up in the warehouse area. The positioning error parameters of the corresponding IoT collection device are retrieved according to the device identification. The positioning error parameters include spatial positioning error and allowable instantaneous drift duration. The warehouse management system obtains the circulation operation information corresponding to the material identification information. The circulation operation information includes operation type, operation time, starting storage location and target storage location. The operation type includes inbound operation, transfer operation and outbound operation. The location awareness information and the circulation operation information are associated with the material identification information, and time-series alignment is performed according to the collection time and the operation time.

3. The method for dynamic inventory management of PETG film rolls based on the Internet of Things according to claim 2, characterized in that, Establishing the membrane roll status record includes: The membrane roll identifier is determined based on the material identification information, and a material status index is established using the membrane roll identifier. The location sensing information corresponding to the same membrane roll identifier is arranged according to the collection time to form a material location change trajectory, and the device identifier corresponding to each location sensing information is recorded in the material location change trajectory. The circulation operation information is associated with the material location change trajectory according to the operation time, and sample status markers are set for each location sensing information. The sample status markers include a pending confirmation marker, a normal confirmation marker, and an abnormal confirmation marker. The membrane roll identifier, the material location change trajectory, the circulation operation information, and the sample status mark are associated to form the membrane roll status record.

4. The method for dynamic inventory management of PETG film rolls based on the Internet of Things according to claim 3, characterized in that, Determining the range of stable positions includes: From the material location change trajectory, the location perception information with the sample status marked as normal confirmation is selected, and the location perception information during the execution period of the warehousing operation, the transfer operation or the outbound operation is excluded to form a stable location sample set. The center position is determined based on the position sensing information of each position in the stable position sample set, and the distance between each position sensing information and the center position is determined. The sum of the maximum value of the distances and the spatial positioning error is determined as the boundary distance, and the area defined by the boundary distance with the center position as the reference is taken as the stable position range.

5. The method for dynamic inventory management of PETG film rolls based on the Internet of Things according to claim 4, characterized in that, When the PETG membrane roll lacks the historical location-aware information required to form the stable location sample set, including: The storage location calibration area is determined based on the target storage location corresponding to the storage operation. The boundary of the storage location calibration area is extended outward by the distance corresponding to the spatial positioning error to form an initial stable location range. After the warehousing operation is completed, location sensing information is continuously collected, and location sensing information that has been verified to be normal after a second verification is marked as a normal confirmation mark. When the number of location perception information samples with normal confirmation marks reaches a set number, the stable location range is redefined by selecting the location perception information with normal confirmation marks to determine the center position and using the sum of the maximum distance and the spatial positioning error as the boundary distance.

6. The method for dynamic inventory management of PETG film rolls based on the Internet of Things according to claim 4, characterized in that, Determining the valid deviation includes: Determine whether the location sensing information obtained in each acquisition cycle is within the stable location range; When the location sensing information of a collection cycle is outside the stable location range, a deviation candidate record is established, and the deviation start time and corresponding location sensing information are recorded. When subsequent location sensing information returns to the stable location range before reaching the number of consecutive acquisition cycles, the deviation candidate record is deleted; When the number of consecutive acquisition cycles in which the location sensing information is continuously outside the stable location range reaches the number of consecutive acquisition cycles, the deviation candidate record is determined as a valid deviation, and the location change trajectory corresponding to the valid deviation is formed based on the location sensing information after the deviation start time. The number of continuous acquisition cycles is determined by rounding up the ratio between the allowed instantaneous drift duration and the acquisition cycle of the IoT acquisition device.

7. The method for dynamic inventory counting of PETG film rolls based on the Internet of Things according to claim 6, characterized in that, When matching the effective deviation corresponding to the position change trajectory with the flow operation information, it includes: From the warehousing business data, select the transfer operation information with the same film roll identifier and whose operation time and the time difference between the deviation from the start time do not exceed the set synchronization time to form candidate transfer operation information. The set synchronization time is determined based on the maximum time synchronization error between the warehousing management system and the Internet of Things acquisition device. It is determined whether the starting storage position in the candidate flow operation information matches the stable position range, whether the target storage position matches the end position of the position change trajectory, and whether the change direction of the position change trajectory points from the starting storage position to the target storage position. When all the above judgment results are a match, the corresponding candidate circulation operation information will be determined as valid circulation operation information, and the corresponding materials will be determined as normal circulation materials. When no valid transfer operation information exists, the corresponding material will be identified as the dynamic inventory object.

8. The method for dynamic inventory counting of PETG film rolls based on the Internet of Things according to claim 7, characterized in that, When controlling the target IoT data acquisition device to perform secondary verification of the dynamically inventoried object, the following steps are included: The target storage location is determined based on the end position of the corresponding position change trajectory of the effective deviation, and the collection coverage area is limited to the target storage location and the storage locations adjacent to the target storage location. The IoT collection device whose collection coverage includes the target storage location enters the verification collection state, and the collection cycle of the target IoT collection device is switched to the verification collection cycle. The verification collection cycle is determined by completing no less than three collections within the allowed instantaneous drift duration. During the continuous verification period, material identification information and location awareness information of the dynamic inventory object are collected. When the material identification information obtained from each collection points to the same material and the location awareness information is concentrated in the same storage location, the same storage location is determined as the verification storage location. When the verification storage location is within the range of the stable location, or when the verification storage location matches the target storage location in the valid transfer operation information, a normal inventory confirmation result is generated; when the verification storage location is outside the range of the stable location and there is no corresponding valid transfer operation information, an abnormal inventory confirmation result is generated.

9. The method for dynamic inventory counting of PETG film rolls based on the Internet of Things according to claim 8, characterized in that, When updating the membrane roll status record based on the inventory confirmation results, the following is included: When the normal inventory confirmation result is obtained, the location awareness information obtained from the secondary verification is set as the normal confirmation mark, and the normal inventory confirmation result is associated with the corresponding material location change trajectory. When the normal inventory confirmation result corresponds to valid transfer operation information, and the location sensing information is continuously collected for a set number of cycles after the transfer operation is completed and remains at the target storage location, the corresponding location sensing information is added to the stable location sample set, and the stable location range is redefined. When the abnormal inventory confirmation result is obtained, the location awareness information obtained from the secondary verification is set as an abnormal confirmation mark, the abnormal location change is recorded and the material location change trajectory is updated, the current stable location range remains unchanged, and location awareness information with abnormal confirmation marks is prohibited from entering the stable location sample set.

10. An IoT-based dynamic inventory system for PETG film rolls, used to implement the IoT-based dynamic inventory method for PETG film rolls in stock as described in any one of claims 1-9, characterized in that, include: The data acquisition module is used to acquire material identification information and location perception information corresponding to PETG film rolls through IoT acquisition devices, acquire corresponding circulation operation information through the warehouse management system, and acquire positioning error parameters of the IoT acquisition devices. The status record establishment module is used to establish a membrane roll status record based on the material identification information, the location perception information and the circulation operation information. The membrane roll status record includes the material location change trajectory and sample status markers of the location perception information. A stable range determination module is used to determine a stable position range based on historical position sensing information with normal confirmation markers and the positioning error parameters. The deviation recognition module is used to compare the currently continuously collected position sensing information with the stable position range, and to determine a valid deviation when the position sensing information is outside the stable position range for a set number of consecutive collection cycles. The flow matching module is used to match the position change trajectory corresponding to the effective deviation with the operation time, starting storage position and target storage position in the flow operation information, and to determine the dynamic inventory object when there is no effective flow operation information; The inventory control module is used to determine the target IoT data collection device based on the warehouse area where the dynamic inventory object is located, control the target IoT data collection device to adjust the collection coverage and collection cycle, perform secondary verification on the dynamic inventory object, and obtain the inventory confirmation result. The status update module is used to update the membrane roll status record based on the inventory confirmation result, and only use the position awareness information with normal confirmation mark to update the stable position range.

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