Three-dimensional warehouse positioning method and system fused with forklift operation mechanism

Abstract

The invention discloses a three-dimensional warehouse positioning method and system fused with a forklift operation mechanism, and the method comprises the steps: deploying a multi-source sensor in each scene of cargo loading, unloading and transportation based on the operation mechanism of a forklift; a positioning process is established for an unloading and warehousing operation mechanism and an ex-warehouse loading operation mechanism of the forklift based on multi-source sensors deployed in all scenes; based on an RFID positioning device and an IMU positioning device, continuous plane positioning under a forklift operation mechanism is carried out; the radio frequency signal intensity is obtained based on the RFID positioning device, and elevation positioning under the forklift operation mechanism is carried out. According to the technical scheme provided by the embodiment of the invention, continuous, accurate and stable three-dimensional warehouse positioning in the railway freight yard can be realized in the cargo loading and unloading transportation process in the railway freight yard.

Description

Technical Field

[0001] This invention relates to the field of railway freight yard resource scheduling technology, specifically to a three-dimensional warehouse positioning method and system that integrates forklift operation mechanism. Background Technology

[0002] Faced with increasingly fierce competition in railway freight, the railway is gradually promoting the informatization of railway freight yards in order to improve the high-quality development of railway freight. Forklifts are indispensable transportation equipment in the daily operations of railway freight yards, participating in the loading and unloading of goods. The operating environment of railway freight yard forklifts is indoor warehouses and railway station platforms with high obstacle density, and the forklift's running trajectory reflects the information flow of goods in the complex railway freight yard.

[0003] Traditional railway freight yard transportation requires a large amount of human and material resources to operate and schedule forklifts in order to organize and manage the freight yard. It is characterized by low informatization and low transportation efficiency, making it difficult to adapt to the increasingly busy railway freight yard transportation organization needs, and it does not conform to the current industry direction of railway freight transportation transformation towards modern logistics.

[0004] Therefore, there is an urgent need for a new type of forklift positioning solution for railway freight yards to support the improvement of intelligent scheduling and refined management of railway freight yards. Summary of the Invention

[0005] This invention provides a method and system for positioning automated warehouses that integrates forklift operation mechanisms.

[0006] In a first aspect, the present invention provides a method for positioning in an automated warehouse that integrates forklift operation mechanisms, comprising:

[0007] Based on the forklift's operating mechanism, multi-source sensors are deployed in various scenarios of cargo loading, unloading, and transportation; the multi-source sensors include at least one of RFID positioning devices, IMU positioning devices, and GNSS positioning devices.

[0008] Based on the multi-source sensors deployed in various scenarios, a positioning process is established for forklifts in unloading and warehousing operations and loading and unloading operations.

[0009] Continuous planar positioning under forklift operation mechanism based on RFID positioning device and IMU positioning device;

[0010] Elevation positioning under forklift operation is performed by acquiring radio frequency signal strength using an RFID positioning device.

[0011] Furthermore, the scenarios for loading and unloading goods include: loading and unloading in truck beds, transportation using forklifts, and loading and unloading on racks.

[0012] Furthermore, the deployment of multi-source sensors in various scenarios of cargo loading, unloading, and transportation includes:

[0013] In the scenario of loading and unloading cargo in a truck bed, RFID readers are deployed on forklifts and RFID electronic tags are deployed on the truck bed; the basic information of the goods and the truck bed number are read by scanning the RFID electronic tags deployed on the truck bed with the RFID readers.

[0014] In forklift transportation scenarios, GNSS receivers, RFID readers, and IMU inertial navigation sensors are deployed on the forklifts, and RFID tags are deployed on the warehouse roof to form an RFID tag matrix for scanning and positioning. When the forklift is operating indoors, the RFID reader scans the positioning tags on the warehouse roof, performs RFID positioning based on RSSI ranging technology, and outputs the position using the IMU inertial measurement unit. When the forklift is operating outdoors, the GNSS receiver receives satellite signals transmitted by high-precision satellites, performs GNSS positioning based on GNSS positioning technology, and outputs the position using the IMU inertial measurement unit.

[0015] In rack loading and unloading scenarios, RFID readers are deployed on forklifts and RFID electronic tags are deployed on racks; the basic information of the goods and the rack number are read by scanning the RFID electronic tags deployed on the racks with RFID readers.

[0016] Furthermore, the positioning process under the unloading and warehousing operation mechanism includes:

[0017] In response to the unloading and warehousing instruction, the forklift obtains the unloading vehicle number, the unloading and warehousing goods invoice information, and the storage location information, and begins the current operation process;

[0018] The forklift moves to the designated unloading compartment and performs initial positioning using a GNSS receiver, RFID reader, and IMU inertial measurement unit;

[0019] When the forklift arrives at the designated unloading compartment, it compares the information of the goods with the compartment by scanning the RFID tags of the compartment and the goods, and completes the goods verification by measuring the volume and weight of the goods.

[0020] Forklifts transport goods to designated loading racks, and their location is tracked using GNSS receivers, RFID readers, and inertial measurement units.

[0021] When a forklift carries goods to the designated loading rack, it binds the goods to the rack by scanning the RFID tags on the rack and the goods, and performs elevation positioning based on RSSI ranging using radio frequency signals.

[0022] Combine RFID positioning devices to measure cargo elevation and record the positioning information of unloading vehicles and the location information of goods received into the warehouse.

[0023] The forklift proceeds to the next loading / unloading operation or maintenance.

[0024] Furthermore, the positioning process under the outbound loading operation mechanism includes:

[0025] In response to the outbound loading instruction, the forklift obtains the loading vehicle number, the loading and outbound goods invoice information, and the storage location information, and begins the current operation process;

[0026] The forklift moves to the designated unloading rack and performs initial positioning using a GNSS receiver, RFID reader, and IMU inertial measurement unit;

[0027] When the forklift arrives at the designated unloading rack, it binds the goods to the rack by scanning the RFID tags on the rack and the goods. It then verifies the goods by measuring their volume and weight and performs elevation positioning based on RSSI ranging using radio frequency signals.

[0028] Forklifts transport goods to designated loading compartments, and their location is tracked using GNSS receivers, RFID readers, and inertial measurement units.

[0029] When a forklift carries goods to the designated loading compartment, the information of the goods and the compartment is compared by scanning the RFID tags of the compartment and the goods.

[0030] Record the location information of the outbound shelving and the location information of the vehicle receiving the outbound goods;

[0031] The forklift proceeds to the next loading / unloading operation or maintenance.

[0032] Furthermore, the process of continuous planar positioning under the forklift operation mechanism includes:

[0033] Initial positioning of the forklift in the navigation coordinate system is obtained based on the RFID positioning device;

[0034] State variables during forklift transportation are constructed based on IMU positioning devices;

[0035] The measurement equation for the combined positioning of the forklift is obtained based on the state variables, and it is determined whether the combined positioning mode needs to be switched.

[0036] Based on the forklift's initial positioning and state variables, the current state of the forklift is updated in real time.

[0037] Furthermore, the process of performing elevation positioning under the forklift operation mechanism includes:

[0038] Construct an adaptive spatial path loss model between RFID readers and RFID electronic tags;

[0039] Obtain the radio frequency signal strength between the RFID reader and the RFID tag at different distances;

[0040] Elevation positioning is performed based on the current radio frequency signal strength obtained by the RFID reader.

[0041] Secondly, this invention provides an automated warehouse positioning system that integrates forklift operation mechanisms, comprising:

[0042] A sensor deployment module is used to deploy multi-source sensors in various scenarios of cargo loading, unloading and transportation based on the forklift operation mechanism; the multi-source sensors include at least one of: RFID positioning device, IMU positioning device and GNSS positioning device;

[0043] The positioning process construction module is used to establish a positioning process for forklifts in unloading and loading operations based on multi-source sensors deployed in various scenarios.

[0044] A continuous planar positioning module is used for continuous planar positioning under forklift operation mechanisms based on RFID positioning devices and IMU positioning devices.

[0045] The elevation positioning module is used to obtain the radio frequency signal strength based on the RFID positioning device and perform elevation positioning under the forklift operation mechanism.

[0046] Thirdly, embodiments of the present invention provide an electronic device, the electronic device comprising:

[0047] At least one processor; and a memory communicatively connected to the at least one processor;

[0048] The memory stores a computer program that can be executed by at least one processor, such that the at least one processor is able to perform the steps of the automated warehouse positioning method that integrates a forklift operation mechanism according to any embodiment of the present invention.

[0049] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing computer instructions, which are used to cause a processor to execute the steps of the automated warehouse positioning method that integrates a forklift operation mechanism according to any embodiment of the present invention.

[0050] Compared with the prior art, the present invention has the following advantages:

[0051] The technical solution in this invention first deploys multi-source sensors in various scenarios of cargo loading, unloading, and transportation based on the forklift's operating mechanism. Then, based on the multi-source sensors deployed in each scenario, a positioning process is established for the forklift in both unloading / warehousing and loading / unloading operations. Next, continuous planar positioning under the forklift operating mechanism is performed using RFID and IMU positioning devices. Finally, elevation positioning under the forklift operating mechanism is performed based on the radio frequency signal strength obtained from the RFID positioning device. This method can adapt to complex railway freight yard positioning environments and achieve high-quality automated warehouse positioning of forklift cargo. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only preferred embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 A flowchart illustrating a three-dimensional warehouse positioning method integrating forklift operation mechanism provided in an embodiment of the present invention;

[0054] Figure 2 This is a schematic diagram of a railway freight yard positioning sensor deployment scenario provided in an embodiment of the present invention;

[0055] Figure 3 This is a flowchart illustrating the continuous planar positioning process for forklifts provided in an embodiment of the present invention.

[0056] Figure 4 A flowchart illustrating the overall three-dimensional warehouse positioning scheme provided in this embodiment of the invention;

[0057] Figure 5 This is a schematic diagram of the structure of an automated warehouse positioning system that integrates forklift operation mechanism, provided in an embodiment of the present invention.

[0058] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0059] 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.

[0060] Figure 1This is a flowchart illustrating a positioning method for an automated warehouse that integrates forklift operation mechanisms, provided by an embodiment of the present invention. This embodiment is applicable to positioning different transportation stages during loading and unloading in railway freight yards. The method can be executed by an automated warehouse positioning system that integrates forklift operation mechanisms. This system can be implemented using software and / or hardware and can be configured in electronic devices.

[0061] like Figure 1 As shown, the method specifically includes:

[0062] S1, based on the forklift operation mechanism, deploys multi-source sensors in various scenarios of cargo loading, unloading and transportation.

[0063] The scenarios for cargo loading and unloading include: loading and unloading in truck beds, forklift transportation, and loading and unloading on racks. Multi-source sensors include at least one of RFID positioning devices, IMU positioning devices, and GNSS positioning devices.

[0064] Preferably, in the scenario of loading and unloading goods in a truck bed, an RFID reader is deployed on the forklift, and RFID electronic tags are deployed on the truck bed. The RFID reader scans the RFID electronic tags deployed on the truck bed to read the basic information of the goods and the truck bed number. In the scenario of forklift transportation, a GNSS receiver, an RFID reader, and an IMU inertial measurement unit are deployed on the forklift, and RFID tags are deployed on the top of the warehouse to form an RFID tag matrix for scanning and positioning. In the scenario of loading and unloading goods on a rack, an RFID reader is deployed on the forklift, and RFID electronic tags are deployed on the rack. The RFID reader scans the RFID electronic tags on the rack to read the basic information of the goods and the rack number.

[0065] Furthermore, when the forklift is operating indoors, it scans the positioning tag on the top of the warehouse with an RFID reader, performs RFID positioning based on RSSI ranging technology, and outputs the position using an IMU inertial measurement unit; when the forklift is operating outdoors, it receives satellite signals transmitted by high-precision satellites through a GNSS receiver, performs GNSS positioning based on GNSS positioning technology, and outputs the position using an IMU inertial measurement unit.

[0066] Figure 2 This is a schematic diagram of a railway freight yard positioning sensor deployment scenario provided by an embodiment of the present invention, such as... Figure 2 As shown, the sensor deployment scenarios mainly include: truck loading and unloading scenarios, forklift transportation scenarios, and rack loading and unloading scenarios.

[0067] In freight car loading and unloading scenarios: When loading or unloading within train or freight car compartments accessible to forklifts, it is necessary to confirm the basic information of the goods. To address this, RFID readers are deployed on forklifts, and RFID electronic tags are deployed on the freight cars. By scanning the RFID electronic tags on the freight cars with the RFID readers, the basic information of the goods and the freight car number are read, enabling forklift-goods binding, goods confirmation, and subsequent horizontal positioning and tracking of the goods during transportation in the railway freight yard.

[0068] In forklift operation scenarios: Forklifts move and operate within railway freight yards, requiring real-time monitoring of their operational status. To address this, a GNSS receiver, RFID reader, and IMU (Inertial Measurement Unit) are deployed on the forklift, while RFID tags are deployed on the warehouse roof to form an RFID tag matrix for scanning and positioning. Indoors, RFID positioning is achieved using RSSI ranging technology, while outdoors, high-precision GNSS positioning is achieved using high-precision satellites. This, combined with the IMU, outputs the position, achieving comprehensive and precise positioning. The RFID tag matrix covers the entire operating range of the forklift within the warehouse. The RFID reader on the forklift scans the positioning tags on the warehouse roof, using RSSI ranging technology for RFID positioning within the warehouse. The GNSS positioning device provides continuous, stable, and high-precision satellite positioning in the outdoor area of ​​the railway freight yard. In different scenarios, the positioning information is transmitted via the forklift's embedded host computer, fused with the IMU data, to output the position.

[0069] In rack loading and unloading scenarios, it is necessary to monitor the loading and unloading status of goods at the racks. To achieve this, RFID readers are deployed on forklifts, and RFID tags are deployed on the racks. By scanning the RFID tags on the racks with the RFID readers, basic information about the goods and the rack number can be obtained. In addition to binding goods to the racks, this also allows for continuous elevation positioning of goods using RSSI ranging, thus improving the positioning solution for automated warehouses.

[0070] It should be noted that RFID positioning devices consist of a read / write unit and an electronic transceiver. They automatically identify specific objects and acquire information by transmitting and receiving radio frequency signals. RFID technology can simultaneously identify the different characteristics of multiple objects, making it suitable for the need to simultaneously identify multiple pieces of information from different equipment such as forklifts and goods in railway freight yards. RFID technology enables remote automatic identification, so the transceiver unit does not need to be exposed to the environment, resulting in high physical reliability and low cost, making it suitable for the complex environment of railway freight yards. IMU positioning devices include a gyroscope, accelerometer, and corresponding inertial measurement unit. IMU positioning devices have advantages such as autonomous positioning, immunity to external interference, and continuous real-time positioning. Installing them on forklifts in railway freight yards can provide a low-cost solution for forklift positioning. GNSS positioning devices calculate the precise location of ground users by receiving signals from at least four satellites. Generally, the more satellite signals received, the higher the positioning accuracy and reliability. However, GNSS positioning technology is highly limited by the environment; its positioning effect drops sharply in indoor scenarios with obstructed sunlight. Therefore, in railway freight yards with both indoor and outdoor environments, it is necessary to construct a combined positioning scheme with other positioning sensors.

[0071] When the aforementioned positioning devices perform single-point positioning, they are more or less limited by their own principles and affected by external environmental interference. For example, when RFID signals are transmitted and received, external RFID radio frequency signals or other electromagnetic interference in the freight yard can significantly affect the positioning results; the positioning error of inertial positioning devices will increase over time; GNSS positioning devices are limited by the weak satellite signal strength received in indoor scenes, making positioning impossible. Therefore, this invention integrates the advantages of multiple sensors for combined positioning, improving positioning quality and providing a three-dimensional warehouse positioning method that integrates the forklift operation mechanism of railway freight yards: by equipping forklifts with multi-source sensors and combining them with the forklift operation mechanism in railway freight yards, it achieves the collection of cargo information, continuous and accurate positioning of forklifts in the freight yard, and positioning of cargo in the three-dimensional warehouse.

[0072] In this embodiment of the invention, by deploying positioning receiving and transmitting devices such as RFID, IMU, and GNSS in railway freight yards, a hardware foundation is provided for the positioning scheme of the "freight-car-carriage-rack" automated warehouse. Sensors in railway freight yards need to be adaptively deployed by integrating inbound and outbound loading and unloading operations. Forklifts, as the artery of freight yard transportation, are an important means of information flow and data network construction; therefore, sensor deployment is implemented based on the operating mechanism of forklifts in different scenarios.

[0073] S2, based on multi-source sensors deployed in various scenarios, establishes a positioning process for forklifts in unloading and warehousing operations and loading and unloading operations.

[0074] Preferably, the positioning process under the unloading and warehousing operation mechanism includes:

[0075] S2011, in response to the unloading and warehousing instruction, the forklift obtains the unloading truck compartment number, the unloading and warehousing goods invoice information, and the storage location information.

[0076] S2012, the forklift proceeds to the designated unloading compartment and performs initial positioning using a GNSS receiver, RFID reader, and IMU inertial measurement unit.

[0077] The forklift travels to the truck bed where it needs to be unloaded, and uses RFID / IMU / GNSS combined positioning for initial positioning along the way to monitor the forklift status in real time.

[0078] S2013, the forklift arrives at the designated unloading compartment, verifies the goods and the compartment by scanning the RFID tags of the compartment and the goods, and completes the inspection by measuring the volume and weight of the goods.

[0079] When the forklift arrives at the designated truck bed to pick up goods, it scans the RFID tag of the goods to obtain information such as the type, quantity, weight, volume, destination, and unloading truck bed, thus binding the goods. Other sensors installed on the forklift measure the volume and weight of the goods, and at the same time scan the RFID tag of the truck bed. The three pieces of information are compared to ensure that the goods information is accurate.

[0080] S2014, forklifts transport goods to designated loading racks, with position tracking achieved via GNSS receivers, RFID readers, and IMU inertial measurement units.

[0081] The forklift carries goods to the designated shelf. During the journey, the forklift's position is tracked by a combination of RFID / IMU / GNSS positioning, and the forklift's status is monitored in real time. The status of the goods follows the status of the forklift, and the goods' location is synchronized at all times.

[0082] S2015: When a forklift carries goods to the designated loading rack, it binds the goods to the rack by scanning the RFID tags on the rack and the goods, and performs elevation positioning based on RSSI ranging using radio frequency signals.

[0083] When the forklift arrives at the designated warehouse unloading point and places the goods on the shelves, the forklift RFID reader reads the RFID tags on the shelves. This binds the goods to the shelves and performs elevation positioning based on RSSI ranging via radio frequency signals, thus improving the positioning solution of the automated warehouse. Therefore, the RFID reader mounted on the forklift should be deployed on the telescopic boom.

[0084] S2016 combines RFID positioning devices to measure cargo elevation and record the location information of unloading vehicles and the location information of goods received into the warehouse.

[0085] By using elevation positioning and elevation ranging, the positioning of goods in the automated warehouse is realized. Finally, the recorded positioning information of unloading vehicles and the positioning information of the receiving goods are uploaded to the dispatch information system.

[0086] S2017, the forklift enters the next loading / unloading operation or maintenance process, realizing the closed loop of the continuous positioning process of the forklift for this unloading and warehousing.

[0087] Preferably, the positioning process under the outbound loading operation mechanism includes:

[0088] S2021, in response to the outbound loading instruction, the forklift obtains the loading vehicle number, the loading and outbound goods invoice information, and the storage location information, and begins the current operation process.

[0089] S2022, the forklift proceeds to the designated unloading rack and performs initial positioning using a GNSS receiver, RFID reader, and IMU inertial measurement unit.

[0090] S2023, the forklift arrives at the designated unloading rack, binds the goods to the rack by scanning the RFID tags of the rack and the goods, completes the goods verification by measuring the volume and weight of the goods, and performs elevation positioning based on RSSI ranging through radio frequency signals.

[0091] S2024, forklifts transport goods to designated loading compartments, with location tracking achieved via GNSS receivers, RFID readers, and inertial measurement units.

[0092] S2025, when a forklift carrying goods arrives at the designated loading compartment, the information of the goods and the compartment is compared by scanning the RFID tags of the compartment and the goods.

[0093] When the forklift places goods in the truck bed, it reads the RFID tag in the truck bed using an RFID reader, compares the obtained information with the truck bed signal information in the loading instruction, and unloads and loads the goods after confirming that there is no error.

[0094] S2026 records the location information of the outbound shelving and the location information of the vehicle receiving the outbound goods, and uploads it to the dispatch information system.

[0095] S2027, the forklift enters the next loading / unloading operation or maintenance process, realizing the closed loop of the continuous positioning process of the forklift for this unloading and warehousing.

[0096] In this embodiment of the invention, by deploying sensors at different stages of transportation, the forklift operation mechanism is deeply integrated, and a continuous positioning process for the forklift during loading and unloading is implemented.

[0097] S3, based on RFID and IMU positioning devices, updates the current status of the forklift in real time.

[0098] Figure 3 This is a flowchart illustrating the continuous planar positioning process for forklifts provided in an embodiment of the present invention, as follows: Figure 3 As shown, the continuous planar positioning of forklifts in railway freight yards relies on the error fusion and correction of multiple positioning systems. At the start of forklift loading and unloading operations, initial positioning based on RFID is performed, with the inertial measurement unit as the reference system. The positioning system status monitoring determines the positioning system that needs to be fused. The error difference of multiple positioning systems is combined and filtered. Through continuous measurement updates and status updates, the continuous and accurate forklift position is calculated, realizing continuous forklift position tracking.

[0099] Preferably, the process of continuous planar positioning under the forklift operation mechanism includes:

[0100] S301, obtains the initial positioning of the forklift in the navigation coordinate system based on the RFID positioning device.

[0101] After the forklift starts, its initial position in the navigation coordinate system is obtained through the RFID positioning device. The RFID positioning system includes the transformation between the relative coordinate system and the navigation coordinate system within the railway freight yard. Therefore, based on the initial position, subsequent positioning schemes output position parameters in the navigation coordinate system, unifying the position coordinate system of the multi-source sensor positioning system within the freight yard.

[0102] S302, constructing state variables during forklift transportation based on IMU positioning device.

[0103] S3021, Construct the error equation for the state variables. Setting the inertial measurement unit as the reference system, this stage involves continuous planar positioning; only the north and east position parameters need to be considered. Therefore, the combined system state variables are constructed based on the errors of the inertial measurement unit, and the error equation is:

[0104]

[0105] In the formula, , , These represent the velocity error, position error, and random constant offset of acceleration in the plane, respectively. , These represent the misalignment angle and the random constant drift of the gyroscope on the three-axis solid, respectively.

[0106] S3022, Construct the dynamic continuous state equations for the state variables. The system's dynamic continuous state equations are:

[0107]

[0108] In the formula, Here is the state transition matrix. Here is the system noise matrix. This is the system noise vector.

[0109] S3023, Construct the discrete state equations for the state variables. After discretization, the discrete state equations of the system are obtained:

[0110]

[0111] In the formula, The discrete state transition matrix, This is the noise vector under the dynamic model.

[0112] S303: Obtain the measurement equation of the forklift positioning combination based on the state variables, and determine whether it is necessary to switch the positioning combination.

[0113] The observed value is the difference between the position output by the forklift's inertial navigation system and the current auxiliary positioning system. The navigation parameters of the auxiliary positioning system include the position output in the north and east directions. The measurement equation for the forklift's combined positioning is:

[0114]

[0115] in:

[0116]

[0117] In the formula, For observation; This represents the radius of curvature of the meridian. L represents the radius of curvature of the ramid; L with superscripts N and E represent the latitude and longitude of the moving body's position, respectively, and its subscripts indicate the corresponding sensor; This is the measurement transformation matrix; To measure noise, including northward position error and eastward position error .

[0118] Establish a state monitoring model for the positioning system, and calculate the monitoring model parameters based on the least squares method according to the above measurement equations:

[0119]

[0120] In the formula, For the power formation.

[0121] Calculation of measurement noise :

[0122]

[0123] Calculate the sum of squares of the measured noise :

[0124]

[0125] In this model, the measurement noise follows a normal distribution, so its sum of squares obey The distribution has m-2 degrees of freedom, where m is the dimension of measurement noise.

[0126] By setting threshold parameters To determine whether the current location scheme needs to be switched:

[0127]

[0128]

[0129] In the formula, This is the critical value for the chi-square test. To switch thresholds, This is the current test value. If... If the current location scheme is correct, then there is no need to switch the positioning scheme; otherwise, the current positioning scheme needs to be switched to another combination positioning method.

[0130] S304 updates the current state of the forklift in real time based on its initial positioning and state variables.

[0131] The solution for the forklift combination model employs a time-varying Kalman filter algorithm. Initial state estimates are obtained using initial positioning, followed by continuous "prediction updates" and "measurement updates" in a cyclical manner. The system noise in the state equation is time-varying according to the current state.

[0132]

[0133] in, Let be the noise vector of the time-varying system. b and b are the time-varying parameter and the time-invariant parameter, respectively.

[0134] Prediction updates use the state values ​​and covariance matrix from the previous stage to calculate the predicted values ​​for the current stage. Covariance Matrix .Right now:

[0135]

[0136] In the formula, Q is The expected value.

[0137] Measurement updates are performed by calculating the Kalman gain based on the predicted values ​​and the input measurements, thereby calculating the true coordinates and updating the covariance matrix simultaneously.

[0138]

[0139] In the formula, r is Expected value.

[0140] In this embodiment of the invention, by fusing navigation information output from multiple sensors, the position that best matches the current operating state of the forklift can be predicted, thereby improving positioning accuracy and stability.

[0141] S4 uses the RFID positioning device to obtain the radio frequency signal strength and perform elevation positioning under the forklift operation mechanism.

[0142] The racks in railway freight yards have a multi-layer structure. Therefore, in addition to collecting the horizontal positioning of goods upon entry into the warehouse, it is also necessary to monitor their vertical positioning to achieve three-dimensional warehouse positioning and realize the goal of refined management and control of the freight yard.

[0143] Since the intensity of RFID radio frequency signals is not uniform in space, the distance from the RFID reader on the forklift telescopic boom to the RFID tag on the shelf can be calculated by measuring the signal strength, thus achieving elevation positioning.

[0144] The feedback radio frequency signal emitted by an RFID tag activated by an RFID reader weakens as it moves further away from the signal source. Therefore, based on the change in signal power, a reliable path loss model is established to estimate the distance between the RFID reader and the tag.

[0145] The process of elevation positioning under forklift operation includes:

[0146] S401, construct an adaptive spatial path loss model between RFID readers and RFID electronic tags.

[0147] In the application scenario of this invention, there are no other obstructions between the reader and the electronic tag. Only the addition of Gaussian white noise, consistent with the air environment of a railway freight yard, is needed to construct an adaptive spatial path loss model. The model formula is shown below:

[0148]

[0149] In the formula, d is the current distance between the RFID reader and the electronic tag. This is a reference distance, determined based on the site conditions; The signal strength loss caused by the current distance between the RFID reader and the electronic tag; This refers to the signal strength loss at the reference distance. This is the signal strength loss factor.

[0150] S402, obtain the radio frequency signal strength between the RFID reader and the RFID electronic tag at different distances.

[0151] The RSSI value (signal strength) can be obtained from the above formula when the current distance between the RFID reader and the electronic tag is d. :

[0152]

[0153] Where S is the initial signal strength value.

[0154] In order to To adapt to the radio frequency strength attenuation process in real-world railway freight yard scenarios, an adaptive signal strength loss factor is constructed.

[0155]

[0156] In the formula: Let be the signal strength loss factor at time t; This is the attenuation coefficient, which should be set according to the specific environment.

[0157] Combining the above formulas, we can obtain the relationship between the current radio frequency signal strength and the transmission distance:

[0158]

[0159] S403 performs elevation positioning based on the current radio frequency signal strength obtained by the RFID reader.

[0160] Based on the radio frequency signal strength obtained by the forklift RFID reader, the elevation positioning of the telescopic arm carrying the current goods can be obtained. Combined with the continuous planar positioning in the railway freight yard proposed in this invention, a positioning scheme for the railway freight yard automated warehouse based on the forklift operation mechanism can be realized.

[0161] One objective of this invention is to address various operational scenarios involving forklift loading, unloading, and warehousing in actual railway freight yards. By utilizing multi-source sensor acquisition technologies such as inertial sensors, RFID, and GNSS, combined with a positioning system state monitoring model, and applying integrated positioning and RSSI ranging methods, a continuous, stable, and accurate automated warehouse positioning system for railway freight yards can be achieved. Furthermore, a method integrating the forklift operation mechanism of railway freight yards is proposed. Guided by refined operation management and digitalized process information, and aiming at high-quality forklift positioning in railway freight yards, this method can adapt to complex railway freight yard positioning environments and achieve high-quality automated warehouse positioning of forklift goods. The complete set of equipment, including forklift-mounted gyroscopes, accelerometers, IMU positioning devices, GNSS receivers, and RFID tag readers, has low cost, long service life, and is suitable for long-term deployment, resulting in high economic benefits.

[0162] Figure 4 The flowchart of the overall three-dimensional warehouse positioning scheme provided in the embodiments of the present invention is as follows: Figure 4As shown in the embodiments of the present invention: based on the operation mechanism of forklift entry and exit in railway freight yards, the information transmission mode and positioning requirements of goods in different stages of loading and unloading are grasped, and a forklift positioning process integrating the loading and unloading operation mechanism of railway freight yards is customized; facing the complex operation environment of indoor and outdoor scenarios in railway freight yards, in order to improve the accuracy and continuity of forklift positioning in the freight yard, a continuous planar positioning method for forklifts based on RFID / IMU / GNSS is proposed; through the status monitoring of the positioning system, different positioning systems are allocated for combined positioning, of which the inertial navigation system is the main system, and the other positioning systems continuously correct the positioning error in real time to achieve accurate planar positioning; based on the forklift loading and unloading operation mechanism, "goods-vehicle-carriage-rack" binding confirmation is carried out through RFID in multiple transportation stages; through the RFID reading of the rack by the transportation terminal, the elevation positioning based on RSSI ranging technology is performed to realize the full-process three-dimensional warehouse positioning solution of railway freight yards.

[0163] In this embodiment of the invention, by deeply exploring the railway freight yard transportation process and combining it with the forklift loading and unloading operation mechanism, and based on the deployment of multiple sensors such as forklift RFID, IMU, and GNSS, continuous, accurate and stable three-dimensional warehouse positioning within the railway freight yard is achieved. This provides information technology means for intelligent scheduling and management in railway freight yards and promotes the transformation of railway freight yards towards modernization.

[0164] The technical solution in this invention embodiment, combined with the forklift operation mechanism in the loading and unloading process of railway freight yards, achieves the collection and binding of "cargo-carriage-rack" information by deploying multi-source sensors in different transportation links, covering the inbound and outbound positioning scenarios during the loading and unloading process, and realizing complete and continuous monitoring of forklifts and goods in railway freight yards in time and space; and based on the combined positioning method of RFID / IMU / GNSS and the elevation positioning method based on RSSI ranging technology, it achieves high-quality positioning of forklifts and goods in railway freight yards, improves the organization and management level of railway freight yards, and optimizes the scheduling capability of railway freight system.

[0165] Figure 5 This is a schematic diagram of an automated warehouse positioning system that integrates forklift operation mechanisms, provided by an embodiment of the present invention. Figure 5 As shown, the system specifically includes:

[0166] The sensor deployment module 100 is used to deploy multi-source sensors in various scenarios of cargo loading, unloading and transportation based on the forklift operation mechanism; wherein the multi-source sensors include at least one of RFID positioning device, IMU positioning device and GNSS positioning device.

[0167] The positioning process construction module 200 is used to establish a positioning process for forklifts in unloading and loading operations based on multi-source sensors deployed in various scenarios.

[0168] The continuous planar positioning module 300 is used for continuous planar positioning under forklift operation mechanism based on RFID positioning device and IMU positioning device.

[0169] The elevation positioning module 400 is used to perform elevation positioning under forklift operation by acquiring radio frequency signal strength based on the RFID positioning device.

[0170] The technical solution in this invention, combined with the forklift operation mechanism during loading and unloading in railway freight yards, utilizes multi-source sensors deployed in different transportation stages to achieve information collection and binding of "goods-car-carriage-rack," covering inbound and outbound positioning scenarios during loading and unloading. This enables complete and continuous monitoring of forklifts and goods in railway freight yards in both time and space. Based on a combined RFID / IMU / GNSS positioning method and an elevation positioning method based on RSSI ranging technology, a railway freight yard automated warehouse positioning scheme is constructed. This achieves high-quality positioning of forklifts and goods within the railway freight yard. Compared to existing railway freight yard management systems, this system can improve the organization and management level of railway freight yards and provide reference data for scheduling optimization in railway freight systems.

[0171] Figure 6 This is a schematic diagram of the structure of an electronic device implementing the automated warehouse positioning method integrating a forklift operation mechanism according to embodiments of the present invention. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0172] like Figure 6 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0173] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0174] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, digital signal processors (DSPs), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the automated warehouse positioning method incorporating forklift operation mechanisms.

[0175] In some embodiments, the automated warehouse positioning method integrating forklift operation mechanisms can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the automated warehouse positioning method integrating forklift operation mechanisms described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to perform the automated warehouse positioning method integrating forklift operation mechanisms by any other suitable means (e.g., by means of firmware).

[0176] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0177] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0178] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0179] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0180] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0181] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0182] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0183] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A positioning method for an automated warehouse integrating forklift operation mechanisms, characterized in that, include: Based on the forklift's operating mechanism, multi-source sensors are deployed in various scenarios of cargo loading, unloading, and transportation. The multi-source sensor includes at least one of: an RFID positioning device, an IMU positioning device, and a GNSS positioning device; Based on the multi-source sensors deployed in various scenarios, a positioning process is established for forklifts in unloading and warehousing operations and loading and unloading operations. Continuous planar positioning under forklift operation mechanism based on RFID positioning device and IMU positioning device; Elevation positioning under forklift operation is performed by acquiring radio frequency signal strength using an RFID positioning device.

2. The method according to claim 1, characterized in that, The scenarios for loading and unloading goods include: loading and unloading in truck beds, transportation using forklifts, and loading and unloading on shelves.

3. The method according to claim 1, characterized in that, The deployment of multi-source sensors in various scenarios of cargo loading, unloading, and transportation includes: In the scenario of loading and unloading cargo in a truck bed, RFID readers are deployed on forklifts and RFID electronic tags are deployed on the truck bed; the basic information of the goods and the truck bed number are read by scanning the RFID electronic tags deployed on the truck bed with the RFID readers. In forklift transportation scenarios, GNSS receivers, RFID readers, and IMU inertial navigation sensors are deployed on the forklifts, and RFID tags are deployed on the warehouse roof to form an RFID tag matrix for scanning and positioning. When the forklift is operating indoors, the RFID reader scans the positioning tags on the warehouse roof, performs RFID positioning based on RSSI ranging technology, and outputs the position using the IMU inertial measurement unit. When the forklift is operating outdoors, the GNSS receiver receives satellite signals transmitted by high-precision satellites, performs GNSS positioning based on GNSS positioning technology, and outputs the position using the IMU inertial measurement unit. In rack loading and unloading scenarios, RFID readers are deployed on forklifts and RFID electronic tags are deployed on racks; the basic information of the goods and the rack number are read by scanning the RFID electronic tags deployed on the racks with RFID readers.

4. The method according to claim 1, characterized in that, The positioning process under the unloading and warehousing operation mechanism includes: In response to the unloading and warehousing instruction, the forklift obtains the unloading vehicle number, the unloading and warehousing goods invoice information, and the storage location information, and begins the current operation process; The forklift moves to the designated unloading compartment and performs initial positioning using a GNSS receiver, RFID reader, and IMU inertial measurement unit; When the forklift arrives at the designated unloading compartment, it compares the information of the goods with the compartment by scanning the RFID tags of the compartment and the goods, and completes the goods verification by measuring the volume and weight of the goods. Forklifts transport goods to designated loading racks, and their location is tracked using GNSS receivers, RFID readers, and inertial measurement units. When a forklift carries goods to the designated loading rack, it binds the goods to the rack by scanning the RFID tags on the rack and the goods, and performs elevation positioning based on RSSI ranging using radio frequency signals. Combine RFID positioning devices to measure cargo elevation and record the positioning information of unloading vehicles and the location information of goods received into the warehouse. The forklift proceeds to the next loading / unloading operation or maintenance.

5. The method according to claim 1, characterized in that, The positioning process under the outbound loading operation mechanism includes: In response to the outbound loading instruction, the forklift obtains the loading vehicle number, the loading and outbound goods invoice information, and the storage location information, and begins the current operation process; The forklift moves to the designated unloading rack and performs initial positioning using a GNSS receiver, RFID reader, and IMU inertial measurement unit; When the forklift arrives at the designated unloading rack, it binds the goods to the rack by scanning the RFID tags on the rack and the goods. It then verifies the goods by measuring their volume and weight and performs elevation positioning based on RSSI ranging using radio frequency signals. Forklifts transport goods to designated loading compartments, and their location is tracked using GNSS receivers, RFID readers, and inertial measurement units. When a forklift carries goods to the designated loading compartment, the information of the goods and the compartment is compared by scanning the RFID tags of the compartment and the goods. Record the location information of the outbound shelving and the location information of the vehicle receiving the outbound goods; The forklift proceeds to the next loading / unloading operation or maintenance.

6. The method according to claim 1, characterized in that, The process of continuous planar positioning under the forklift operation mechanism includes: Initial positioning of the forklift in the navigation coordinate system is obtained based on the RFID positioning device; State variables during forklift transportation are constructed based on IMU positioning devices; The measurement equation for the combined positioning of the forklift is obtained based on the state variables, and it is determined whether the combined positioning mode needs to be switched. Based on the forklift's initial positioning and state variables, the current state of the forklift is updated in real time.

7. The method according to claim 1, characterized in that, The process of performing elevation positioning under the forklift operation mechanism includes: Construct an adaptive spatial path loss model between RFID readers and RFID electronic tags; Obtain the radio frequency signal strength between the RFID reader and the RFID tag at different distances; Elevation positioning is performed based on the current radio frequency signal strength obtained by the RFID reader.

8. A positioning system for an automated warehouse integrating forklift operation mechanisms, characterized in that, The system is configured to implement the method according to any one of claims 1-7, the system comprising: A sensor deployment module is used to deploy multi-source sensors in various scenarios of cargo loading, unloading and transportation based on the forklift operation mechanism; the multi-source sensors include at least one of: RFID positioning device, IMU positioning device and GNSS positioning device; The positioning process construction module is used to establish a positioning process for forklifts in unloading and loading operations based on multi-source sensors deployed in various scenarios. A continuous planar positioning module is used for continuous planar positioning under forklift operation mechanisms based on RFID positioning devices and IMU positioning devices. The elevation positioning module is used to obtain the radio frequency signal strength based on the RFID positioning device and perform elevation positioning under the forklift operation mechanism.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and a memory communicatively connected to said at least one processor; The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the steps of the automated warehouse positioning method with integrated forklift operation mechanism as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute the steps of the automated warehouse positioning method with the integrated forklift operation mechanism as described in any one of claims 1-7.

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