A warehouse robot moving positioning method and system

Abstract

This application relates to the field of e-commerce warehouse technology, and in particular to a mobile positioning method and system for a warehouse management robot, comprising the following steps: the robot body is equipped with a cable reel, a gripper, and a control module; the fixed end of the cable reel is located at the charging port and defined as the coordinate origin; the movable end of the cable reel is connected to the robot body and can extend and retract with the movement of the robot body; receiving order information and determining the product ID and quantity in the order information; retrieving the shelf coordinates of the target product and the product coordinates on the shelf from the database, and planning a packaging route based on the coordinate origin; both the shelf coordinates and product coordinates are pre-calibrated and stored in the database with reference to the coordinate origin, and the same type of target products on the same shelf are arranged according to a uniform spacing rule; controlling the robot body to move to the target product position on the corresponding shelf, and performing several picking operations through the gripper to retrieve the target product, thereby reducing the cost of the device.

Description

Technical Field

[0001] This application relates to the field of e-commerce warehouse technology, and in particular to a mobile positioning method and system for a warehouse management robot. Background Technology

[0002] In the current market, some products on e-commerce platforms need to be sold in sets, such as cosmetics, which often include many categories and vary in shape. When fulfilling orders in offline distribution warehouses, the different shapes of various products must be taken into account, so visual robots are often used for order fulfillment.

[0003] However, existing mobile robots in order fulfillment scenarios generally rely on sliding contact lines or cable carriers for power supply to move the robots. While these two methods can achieve continuous power supply, they both require the pre-laying of dedicated physical tracks, such as power supply busbars or cable carrier rails. This not only occupies warehouse floor and space resources, but also significantly increases the design, installation, and maintenance costs of the entire power supply system. This becomes a high fixed expense in the early construction and later renovation of offline warehouses, resulting in high manufacturing costs for the entire offline order fulfillment warehouse. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this application is to provide a mobile positioning method and system for warehouse management robots, which solves the problem of high manufacturing costs for mobile robots in offline distribution warehouses.

[0005] The above-mentioned objective of this application is achieved through the following technical solution: a method for the movement and positioning of a warehouse robot, comprising the following steps: The robot body is equipped with a cable reel, a gripper, and a control module. The fixed end of the cable reel is located at the charging port and is defined as the origin of the coordinate system. The movable end of the cable reel is connected to the robot body and can extend and retract as the robot body moves. Receive order information and confirm the product ID and quantity in the order information; Based on the product ID, retrieve the shelf coordinates where the target product is located and the coordinates of the products on the shelf from the database, and plan the packaging route based on the coordinate origin; Among them, the shelf coordinates and product coordinates are pre-calibrated and stored in the database with reference to the coordinate origin, and the same type of target products on the same shelf are arranged according to a uniform spacing rule; Based on the packaging route and the quantity of goods, the robot body is controlled to move to the target product position on the corresponding shelf, and the target product is retrieved by grabbing the parts and performing several retrieval operations. The robot body is controlled to move to the automatic packaging machine, and the target product is put into the automatic packaging machine by gripping the part. The coordinates of the automatic packaging machine are pre-stored in the database.

[0006] Furthermore, in the step of retrieving the shelf coordinates of the target product and the coordinates of the products on the shelf from the database based on the product ID, and planning the packaging route based on the coordinate origin: Based on the shelf coordinates and product coordinates, determine the theoretical direction and distance of movement of the robot body; Based on the theoretical direction of movement and the theoretical distance of movement, the corresponding path signal set is extracted from the database. The path signal set contains information on several trajectory feature points laid out along the planned route. During the movement, the robot body uses sensors to sense the preset markers on the movement path in real time, and the preset markers correspond one-to-one with the trajectory feature points. When the sensor detects a preset marker point, it triggers the control module to perform real-time coordinate verification to correct the cumulative measurement error caused by the extension and retraction of the cable.

[0007] Furthermore, the sensor includes a length sensor and an angle sensor. The length sensor is used to detect the extension length of the cable from the reel, and the angle sensor is used to detect the deflection angle of the cable relative to the origin of the coordinate system. The theoretical direction and distance of movement of the robot body are determined by the extension length of the pull wire and the deflection angle.

[0008] Furthermore, the control module has a preset positioning deviation threshold; When the deviation between the actual position of the preset marker point sensed in real time and the theoretical position of the trajectory feature point information exceeds the positioning deviation threshold, the control module generates a compensation control signal based on the deviation value, driving the drive wheels of the robot body to make fine adjustments to the steering until the deviation value is restored to within the positioning deviation threshold.

[0009] Furthermore, the location of the coordinate origin within the warehouse plan is determined based on the total number of shelves: When the total number of shelves is less than the preset threshold, the origin of the coordinate system is set at one corner of the outermost shelf. When the total number of shelves is greater than or equal to a preset threshold, all shelves are symmetrically divided into two groups, with the origin of the coordinate system set at the center point of symmetry between the two groups of shelves.

[0010] Furthermore, the gripper is slidably mounted on the robot body via a lifting mechanism; After the control module moves the robot to the shelf coordinates where the target product is located, it also includes a Z-axis positioning step: Obtain the height coordinate value from the product coordinates. The height coordinate value corresponds to the shelf height position of the target product on the shelf. Based on the height coordinates, the control module drives the lifting mechanism to raise or lower the gripper to the target floor height to perform the retrieval operation.

[0011] A mobile positioning system for a warehouse management robot, applied to any of the mobile positioning methods for a warehouse management robot described in the above-mentioned technical solutions, includes: The robot itself; Drive wheels; these are located on the bottom surface of the robot body and are used to drive the robot body to move. The cable reel has a fixed end that is fixed to the charging port and defined as the origin of the coordinate system, and a pull cable at the movable end that is connected to the robot body. The cable reel integrates a length encoder for detecting the extension length of the pull cable and an angle encoder for detecting the deflection angle of the pull cable. The gripper is mounted on the robot body and is used to grip goods. Lifting module; it is installed on the robot body and is used to drive the gripper to move up and down on the robot body; The database stores product IDs, shelf coordinates bound to the product IDs, product coordinates, and automatic packaging machine coordinates. Both shelf coordinates and product coordinates are calibrated with reference to the coordinate origin. The control module communicates with the drive wheel, length encoder, angle encoder, lifting module, and database.

[0012] Furthermore, the control module is also used to calculate the current position of the robot body relative to the coordinate origin in real time based on the change in the length of the pull wire fed back by the length encoder and the change in the angle fed back by the angle encoder during the movement of the robot body, and to perform position correction when the robot body senses the preset marker point on the ground.

[0013] Furthermore, the cable of the cable reel also serves as the power supply cable for the robot body and the physical ranging baseline; The control module uses the real-time extension length of the pull wire as the basis for distance measurement, thus shielding the positioning accuracy from the influence of external wireless signal interference.

[0014] Furthermore, the location of the coordinate origin within the warehouse plan is determined based on the total number of shelves: When the total number of shelves is less than the preset threshold, the origin of the coordinate system is set at one corner of the outermost shelf. When the total number of shelves is greater than or equal to a preset threshold, all shelves are symmetrically divided into two groups, with the origin of the coordinates set at the symmetrical center point between the two groups of shelves.

[0015] In summary, this application includes at least one of the following beneficial technical effects: 1. By directly defining the fixed end of the cable reel as the coordinate origin, the expensive external base station installation required by traditional LiDAR or magnetic strip navigation is eliminated, significantly reducing the cost of warehouse renovation. At the same time, by using physical cables as the ranging medium, the multipath interference of metal shelves in the warehouse to wireless signals such as Wi-Fi / UWB is avoided, fundamentally improving the stability and anti-interference capability of the positioning system. Furthermore, the pre-calibration of coordinate data makes the path planning calculation extremely small and the response speed fast, reducing the manufacturing cost of the entire offline distribution warehouse.

[0016] 2. By introducing discrete preset marker points as absolute position correction anchor points, the problem of plastic deformation of steel wire rope or cumulative error of encoder pulse caused by long-term reciprocating extension and retraction of the reel is effectively solved. Closed-loop control of physical wire distance measurement and absolute correction of marker points is realized, so that the end positioning accuracy of the robot can still be maintained within ΔL after long-distance movement in a large warehouse, which greatly meets the precise picking needs under high-density shelves. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the main steps of the picking process in a warehouse robot's mobile positioning method according to an embodiment of this application. Figure 2 This is a flowchart illustrating the detailed steps of step S300 in the picking process of a warehouse robot's mobile positioning method according to an embodiment of this application. Figure 3 This is a flowchart illustrating the detailed steps of step S500 in the picking process of a warehouse robot's mobile positioning method according to an embodiment of this application. Figure label: Detailed Implementation The present application will be further described in detail below with reference to the accompanying drawings.

[0018] Example, refer to Figure 1 A method for mobile positioning of a warehouse robot, mainly including a picking process, the steps of which are as follows: Step S100: The robot body is equipped with a cable reel, a gripper, and a control module. The fixed end of the cable reel is located at the charging port and is defined as the origin of the coordinate system. The movable end of the cable reel is connected to the robot body and can extend and retract as the robot body moves.

[0019] Step S200: Receive the order information and determine the product ID and product quantity in the order information.

[0020] Step S300: Based on the product ID, retrieve the shelf coordinates where the target product is located and the product coordinates on the shelf from the database, and plan the packing route based on the coordinate origin; Step S400: The shelf coordinates and product coordinates are pre-calibrated and stored in the database with reference to the origin of the coordinate system, and the same type of target products on the same shelf are arranged according to a uniform spacing rule. Step S500: Based on the packaging route and the quantity of goods, control the robot body to move to the target product position on the corresponding shelf, and perform several picking operations by gripping the parts to retrieve the target product; Step S600: Control the robot body to move to the automatic packaging machine, and put the target product into the automatic packaging machine by gripping the component. The coordinates of the automatic packaging machine are pre-stored in the database.

[0021] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: First, after the warehouse management system (WMS) issues an order, the robot control module receives the order information and parses out the product ID, such as the SKU code, and the required quantity.

[0022] The control module uses the fixed end of the cable reel at the charging port as the origin O (0,0), and retrieves the shelf layout coordinates (X1,Y1) and the specific layer coordinates (X2,Y2) of the product on that shelf corresponding to the SKU from the database. The system then executes a multi-objective path planning algorithm: using the coordinates of all products to be picked as nodes, an improved greedy strategy is adopted. Starting from the origin, the Manhattan distance (|X1-X2|+|Y1-Y2|) from the current node to all unvisited nodes is calculated. Each time, the node with the shortest distance and the smallest increase in cable reel length is forcibly selected as the next station, generating the globally optimal picking order. Static shelf columns in the warehouse are introduced as obstacle layers between adjacent nodes, using A... A heuristic search algorithm generates collision-free, locally smooth trajectories, and the evaluation function is: F(n) = G(n) + H(n) Where G(n) is the actual distance moved from the starting point to the current cell, and H(n) uses Euclidean distance (√((dx)²+(dy)²)) as a heuristic estimate to finally form a complete packing route.

[0023] During movement, the control module interrupts at a frequency of 50Hz-100Hz, and calculates the position in real time using a polar coordinate-Cartesian coordinate calculation algorithm: it reads the real-time extension length L of the cable calculated from the pulse count of the length encoder, and reads the real-time deflection angle α of the angle sensor, and substitutes them into the formula: X = L × cosα, Y = L × sinα The sliding mean filter (with a window length of 5-10 sampling points) is used to smooth the cable jitter noise caused by robot vibration, and the absolute coordinates (X,Y) of the current robot end effector in the warehouse plane are output.

[0024] The control module then drives the hub motor to move according to the route, and the cable reel follows to unwind the cable. Once it reaches the target shelf, the mechanical grippers repeatedly grab the cable according to the quantity.

[0025] After being grabbed, the control module drives the movement again based on the pre-stored coordinates (X3, Y3) of the automatic packer in the database. Once it arrives, it rotates the mechanical gripper to directly above the feeding port and releases the gripper to complete the feeding.

[0026] By directly defining the fixed end of the cable reel as the coordinate origin, the expensive external base station installation required by traditional LiDAR or magnetic strip navigation is eliminated, significantly reducing the cost of warehouse renovation. At the same time, by using physical cables as the ranging medium, the multipath interference of metal shelves in the warehouse to wireless signals such as Wi-Fi / UWB is avoided, fundamentally improving the stability and anti-interference capability of the positioning system. Furthermore, the pre-calibration of coordinate data makes the path planning calculation extremely small and the response speed fast, reducing the manufacturing cost of the entire offline distribution warehouse.

[0027] Reference Figure 2 In the steps of retrieving the shelf coordinates of the target product and the coordinates of the products on the shelf from the database based on the product ID, and planning the packing route based on the coordinate origin: Step S310: Determine the theoretical direction and distance of movement of the robot body based on the shelf coordinates and product coordinates; Step S320: Based on the theoretical direction of movement and the theoretical distance of movement, extract the corresponding path signal set from the database. The path signal set contains information on several trajectory feature points laid out along the planned route. Step S330: During the movement, the preset marker points on the movement route are sensed in real time by the sensors set on the robot body, and the preset marker points correspond one-to-one with the trajectory feature point information; Step S340: When the sensor detects the preset marker point, the control module is triggered to perform real-time coordinate verification to correct the cumulative measurement error caused by the extension and retraction of the cable.

[0028] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: After generating the packaging route, the control module calculates the theoretical vector, distance L, and angle θ between two adjacent target points. A set of path signals is pre-stored in the database for this vector, corresponding to equidistant NFC tags or QR code markers laid on the ground. As the robot moves, the bottom-mounted barcode sensor scans the ground in real time. Whenever a pre-set marker is detected, the control module is triggered to execute the absolute marker correction in the cumulative error correction algorithm. Step 1: The control module immediately pauses the polar coordinate calculation and update, and locks the actual coordinates (X real, Y real) calculated by the current reel. Step 2: Read the absolute theoretical coordinates (X coordinate, Y coordinate) stored within the marker point. These coordinates were measured and written using a high-precision total station during the warehouse deployment. Step 3: Calculate the deviation value e = √((X_standard - X_actual)² + (Y_standard - Y_actual)²), and use this deviation value as the quantification result of the current cumulative error; Step 4: "Correction and Zeroing": Write the deviation value (ΔX, ΔY) into the status register as the initial reference for the next moment's calculation, and correct the cumulative measurement error caused by the cable extension and retraction of the reel in this way.

[0029] By introducing discrete preset marker points as absolute position correction anchor points, the problem of plastic deformation of steel wire rope or cumulative error of encoder pulse caused by long-term reciprocating extension and retraction of the reel is effectively solved. Closed-loop control of physical wire distance measurement and absolute correction of marker points is realized, so that the end positioning accuracy of the robot can still be maintained within ΔL after long-distance movement in a large warehouse, which greatly meets the precise picking needs under high-density shelves.

[0030] Reference Figure 1 as well as Figure 2 The sensors include a length sensor and an angle sensor. The length sensor is used to detect the extension length of the cable from the reel, and the angle sensor is used to detect the deflection angle of the cable relative to the origin of the coordinate system. The theoretical direction and distance of movement of the robot body are determined by the extension length of the cable and the deflection angle.

[0031] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: The cable reel integrates a rotary encoder, which functions as a length sensor, and a magnetoresistive angle sensor. The length sensor uses an incremental photoelectric encoder, outputting, for example, 2000 pulses per revolution. Combined with the reel diameter (D=0.12m), it calculates the change in cable length. ΔL = (pulse increment / 2000) × π × D The accumulated values ​​yield the real-time extension length L. An angle sensor, installed at the universal joint of the cable reel's outlet, uses a Hall effect magnetoresistive chip and outputs a 0-5V analog voltage corresponding to a deflection range of -180° to +180°. After sampling by the 12-bit analog-to-digital converter within the control module, the current deflection angle is fitted using a calibration curve. α = k·V_adc + b The control module calculates the robot's position in real time based on a polar coordinate to Cartesian coordinate conversion algorithm. X = L × cosα, Y = L × sinα To suppress measurement noise introduced by mechanical vibration, the algorithm incorporates a nested moving average filter: a circular buffer of length 8 is created, and the oldest value is replaced each time a new value is sampled. The arithmetic mean of the buffer is taken as the final solution output, ensuring that the position data does not change drastically even when the robot stops or accelerates suddenly.

[0032] By using a combination of encoders and angle sensors, the cost is reduced by about 60% compared to expensive inertial measurement units (IMUs) while ensuring positioning accuracy in warehousing scenarios. Furthermore, the polar coordinate transformation algorithm does not require complex filtering and attitude calculation, which reduces the computing power requirements of the control chip, allowing ordinary MCUs to handle high-frequency position refresh tasks, further reducing the cost of the device.

[0033] Reference Figure 1 as well as Figure 2 The control module has a preset positioning deviation threshold. When the deviation between the actual position of the preset marker point sensed in real time and the theoretical position of the trajectory feature point information exceeds the positioning deviation threshold, the control module generates a compensation control signal based on the deviation value, driving the drive wheels of the robot body to make fine adjustments to the steering until the deviation value is restored to within the positioning deviation threshold.

[0034] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: The control module has a preset positioning deviation threshold E, for example, set to ±2cm. When the robot passes the preset marker point for verification, if the calculated deviation e between the current actual coordinates and the coordinates of the theoretical trajectory feature points is greater than 2cm, the control module immediately starts the dead-zone PID position closed-loop adjustment algorithm. The deviation *e* is decomposed into a lateral deviation *e_x* perpendicular to the direction of travel and a longitudinal deviation *e_y* along the direction of travel. Substituting *e_x* into the incremental formula of the digital PID controller: ΔU(k) ​​= ·[e(k) - e(k-1)] + ·e(k) + ·[e(k) - 2e(k-1) + e(k-2)] in, =2.5 is the proportional gain coefficient, which determines the response speed; =0.8 is the integral gain coefficient, which eliminates steady-state static error; =0.3 is the differential gain coefficient, which suppresses overshoot oscillation. e(k) is the lateral deviation at the current moment, e(k-1) is the deviation at the previous moment, and e(k-2) is the deviation at the moment before that. The system converts ΔU(k) ​​into the difference in PWM duty cycles between the left and right drive wheels, generating differential steering torque.

[0035] As the robot moves, the value of e gradually decreases. When e recovers to ≤ the E threshold, the PID controller disengages, and the drive wheels resume straight-line movement at the same speed, forming a dead zone characteristic—that is, it does not move within a small error range, avoiding frequent "snake-like" corrections by the robot due to minor deviations. If the deviation value continues to increase beyond the safety limit, for example, e > 5cm, the control module triggers emergency braking and reports to the maintenance system.

[0036] By setting a dead zone threshold and a PID dynamic compensation mechanism, the robot avoids frequent correction actions due to minor deviations, ensuring the smoothness of the movement path and preventing additional wear on the reel caused by frequent pulling. At the same time, the over-limit alarm function serves as a safety redundancy, ensuring the safety of personnel and equipment under extreme abnormal working conditions.

[0037] Reference Figure 1 as well as Figure 2 The location of the coordinate origin within the warehouse plan is determined based on the total number of shelves: When the total number of shelves is less than the preset threshold, the origin of the coordinate system is set at one corner of the outermost shelf. When the total number of shelves is greater than or equal to a preset threshold, all shelves are symmetrically divided into two groups, with the origin of the coordinate system set at the center point of symmetry between the two groups of shelves.

[0038] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: For small warehouses, such as those with fewer than 20 shelving units, the origin of the coordinate system is set directly at the bottom left corner of the ground projection point of the outermost shelving unit. In this case, the maximum length of the cable reel is approximately the diagonal length of the warehouse. For large warehouses, such as those with 20 or more shelving units, the shelving array is symmetrically divided into two storage areas, A and B, along the central aisle, with the origin of the coordinate system set at the midpoint of the central aisle. The maximum cable extension distance for the robot to move to any shelving unit is only half the length of the warehouse, significantly reducing the risk of cable entanglement and stretching due to its own weight.

[0039] By dynamically selecting the origin position based on the warehouse size, the problem of simple layout and easy construction for small warehouses is solved, while the maximum working stroke of a single reel is effectively reduced for large warehouses. This avoids drooping and touching the ground or damage from excessive stretching caused by excessively long cables, and greatly expands the applicable warehouse area range of this positioning method.

[0040] Reference Figure 3The gripper is slidably mounted on the robot body via a lifting mechanism; after the control module controls the robot body to move to the shelf coordinates where the target product is located, it also includes a Z-axis positioning step: Step S510: Obtain the height coordinate value in the product coordinates. The height coordinate value corresponds to the shelf height position of the target product on the shelf. Step S520: Based on the height coordinate value, the control module drives the lifting mechanism to raise or lower the gripper to the target floor height to perform the picking operation.

[0041] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: The robot body is equipped with a vertical lead screw lifting module, and the mechanical gripper is mounted on the slide. The lead screw lead P_lead = 10mm / rev, that is, when the lead screw rotates one revolution, the slide rises 10mm. The drive motor is a stepper motor with a microstepping of 1600 pulses / rev.

[0042] After reaching the target shelf coordinates (X, Y), the control module further parses the product coordinates from the database. These coordinates include the height value Z, for example, corresponding to shelf levels 1 to 5. The system then executes a Z-axis height layer mapping conversion algorithm: To obtain the height H_bottom of the first shelf from the ground (e.g., H_bottom = 0.3m), the spacing D between adjacent shelves (e.g., D_spacing = 0.35m), and the target shelf number N, use the formula: H target = H bottom + (N layers - 1) × D spacing Calculate the absolute height that the gripper needs to reach. Then convert it into the number of motor drive pulses: Pulse = H_target / P_guide × Subdivision = H_target / 0.01 × 1600 The control module generates a corresponding number of square wave pulses through a pulse generator, driving the stepper motor to rotate. The lead screw then drives the slide to precisely rise or fall to the target layer. Once in position, the gripper extends and triggers the clamping force sensor. Successful clamping is determined when the force feedback reaches a set threshold, such as 5N.

[0043] Building upon the previous XY plane positioning, automatic height adaptation along the Z-axis was added, enabling the robot to automatically handle products of different heights on the three-dimensional shelving, achieving three-dimensional fixed-point retrieval. At the same time, height control was incorporated into the positioning process, avoiding the risk of collisions with the shelving caused by the fixed height of the robotic arm, significantly improving the success rate and safety of retrieval.

[0044] Reference Figures 1-3A mobile positioning system for a warehouse management robot, applicable to any of the mobile positioning methods for warehouse management robots described in the above-mentioned technical solutions, mainly includes a robot body, drive wheels, a cable reel, a gripper, a lifting module, a database, and a control module. The drive wheels are located on the bottom surface of the robot body and are used to drive the robot body to move. The fixed end of the cable reel is fixed to the charging port and defined as the coordinate origin, and the movable end of the cable is connected to the robot body. The cable reel integrates a length encoder for detecting the extension length of the cable and an angle encoder for detecting the deflection angle of the cable. The gripper is located on the robot body and is used to grip goods. The lifting module is located on the robot body and is used to drive the gripper to move up and down on the robot body. The database stores the product ID, the shelf coordinates bound to the product ID, the product coordinates, and the coordinates of the automatic packaging machine. The shelf coordinates and product coordinates are calibrated with reference to the coordinate origin. The control module is communicatively connected to the drive wheels, the length encoder, the angle encoder, the lifting module, and the database.

[0045] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: The entire device consists of an AGV chassis for the robot body, a hub drive motor, a custom cable reel assembly, electric grippers, a lead screw lifting module, a lightweight SQLite database, and an STM32 main control board. The cable reel contains an absolute encoder. During assembly, the cable reel housing is bolted to the plug-in flange of the warehouse charging station, and the end of the cable is connected to the hook at the rear of the AGV chassis. During database initialization, a manually driven robot traverses the entire warehouse, recording and storing the readings at each shelf corner point at the cable length L and angle α. During operation, the STM32 reads encoder data via the CAN bus, controls the lifting module via RS485, and triggers gripper actions via I / O ports.

[0046] All hardware modules of the system adopt industrial common interfaces, such as CAN / RS485 / IO, which are highly integrated and easy to maintain. Compared with traditional systems that rely on laser SLAM mapping, this system does not require a complicated point cloud map construction process. Database calibration can be used immediately, which greatly shortens the implementation cycle of warehouse automation transformation.

[0047] Reference Figures 1-3 The control module is also used to calculate the current position of the robot body relative to the coordinate origin in real time based on the change in the length of the pull wire fed back by the length encoder and the change in the angle fed back by the angle encoder during the movement of the robot body, and to perform position correction when the robot body senses the preset marker point on the ground.

[0048] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: The system's control module interrupts the reading of pulse counts from the length and angle encoders at a frequency of 50Hz, and updates the current coordinates in real time through the kinematics calculation module. Simultaneously, the system includes a ground marker sensing submodule, such as an RFID reader. Whenever the sensing submodule triggers an interrupt, the control module performs a three-step process: freezing, comparing, and correcting the coordinates. This involves freezing the current calculated coordinates, reading the corresponding absolute coordinate library from the RFID reader, calculating the difference, and updating the status register as the initial reference for the next calculation.

[0049] By combining high-frequency interrupts with a real-time correction mechanism, the system maintains real-time and accurate pose perception capabilities even during high-speed movement. The correction process prioritizes hardware interrupts, ensuring that the correction response does not lag behind the robot's motion control cycle, further enhancing the real-time performance and reliability of dynamic positioning.

[0050] Reference Figures 1-3 The cable of the reel also serves as the power supply cable for the robot body and the physical ranging baseline. The control module uses the real-time extension length of the pull wire as the basis for distance measurement, thus shielding the positioning accuracy from the influence of external wireless signal interference.

[0051] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: The cable reel uses a specially designed composite cable containing two power cores—one for robot power and two shielded signal cores for transmitting encoder signals. The composite cable is connected to the external power supply and control bus via slip rings. The analog-to-digital converter in the control module directly samples the voltage drop changes on the signal cores to aid in verifying the cable length. During system operation, the distance is based entirely on the physical length of the composite cable, without relying on any wireless base stations deployed within the warehouse, such as Bluetooth Beacons or UWB anchors.

[0052] By using multiplexed cables for both power supply and ranging baseline, the inherent properties of physical cables are fully utilized, avoiding packet loss and latency issues caused by 2.4G band congestion. This ensures uninterrupted synchronization between positioning commands and power supply, making it suitable for pharmaceutical or precision electronic warehousing environments with stringent electromagnetic compatibility requirements.

[0053] Reference Figures 1-3 The location of the coordinate origin within the warehouse plan is determined based on the total number of shelves: When the total number of shelves is less than the preset threshold, the origin of the coordinate system is set at one corner of the outermost shelf. When the total number of shelves is greater than or equal to a preset threshold, all shelves are symmetrically divided into two groups, with the origin of the coordinates set at the symmetrical center point between the two groups of shelves.

[0054] The method for moving and positioning a warehouse robot provided in this embodiment is implemented as follows: If the number of shelves entered is less than the preset value, such as 30 sets, the system software interface prompts the operator to attach the origin physical marker to the outermost shelf column base; if the number entered is more than 30 sets, the system automatically calculates the centerline of the two rows of shelves and guides the operator to fix the origin mounting piece at the intersection of the centerline and the aisle. The origin mounting piece has a positioning groove to ensure that the cable reel fixing end can be reset to the same physical coordinate after each maintenance and disassembly.

[0055] At the system level, the software algorithm automatically matches the optimal physical origin, reducing the construction threshold and error rate for on-site engineers. Combined with the physical error-proof design of the positioning groove, it ensures the reproducibility of coordinates after maintenance and disassembly of the reel, eliminates system zero-point drift caused by reinstallation, and improves the long-term operation and maintenance convenience and reliability of the system.

[0056] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for the movement and positioning of a warehouse management robot, characterized in that, Including the following steps: The robot body is equipped with a cable reel, a gripper, and a control module. The fixed end of the cable reel is located at the charging port and is defined as the origin of the coordinate system. The movable end of the cable reel is connected to the robot body and can extend and retract as the robot body moves. Receive the order information and determine the product ID and product quantity in the order information; Based on the product ID, retrieve the shelf coordinates where the target product is located and the coordinates of the products on the shelf from the database, and plan the packaging route based on the origin of the coordinates; The shelf coordinates and product coordinates are pre-calibrated and stored in the database with reference to the coordinate origin, and the same type of target products on the same shelf are arranged according to a uniform spacing rule. Based on the packaging route and the quantity of goods, the robot body is controlled to move to the target product position on the corresponding shelf, and the target product is retrieved by performing several retrieval operations using the gripper. The robot body is controlled to move to the automatic packaging machine, and the target product is put into the automatic packaging machine by the gripper. The coordinates of the automatic packaging machine are pre-stored in the database.

2. The method for moving and positioning a warehouse robot according to claim 1, characterized in that, In the step of retrieving the shelf coordinates of the target product and the coordinates of the products on the shelf from the database based on the product ID, and planning the packaging route based on the origin of the coordinates: Based on the shelf coordinates and product coordinates, determine the theoretical direction and distance of movement of the robot body; Based on the theoretical direction of movement and the theoretical distance of movement, the corresponding path signal set is extracted from the database. The path signal set contains information on several trajectory feature points laid out along the planned route. During the movement, the robot body uses sensors to sense preset marker points on the movement route in real time, and the preset marker points correspond one-to-one with the trajectory feature point information; When the sensor detects the preset marker point, it triggers the control module to perform real-time coordinate verification to correct the cumulative measurement error caused by the extension and retraction of the cable reel.

3. The method for moving and positioning a warehouse robot according to claim 2, characterized in that, The sensor includes a length sensor and an angle sensor. The length sensor is used to detect the extension length of the cable of the cable reel, and the angle sensor is used to detect the deflection angle of the cable relative to the origin of the coordinate system. The theoretical direction and distance of movement of the robot body are determined by the extension length of the pull line and the deflection angle.

4. The method for moving and positioning a warehouse robot according to claim 3, characterized in that, The control module has a preset positioning deviation threshold. When the deviation between the actual position of the preset marker point sensed in real time and the theoretical position of the trajectory feature point information exceeds the positioning deviation threshold, the control module generates a compensation control signal based on the deviation value to drive the drive wheels of the robot body to make fine adjustments to the steering until the deviation value is restored to within the positioning deviation threshold.

5. The method for moving and positioning a warehouse robot according to claim 4, characterized in that, The location of the coordinate origin within the warehouse plane is determined based on the total number of shelves: When the total number of shelves is less than a preset threshold, the origin of the coordinate system is set at one corner of the outermost shelf. When the total number of shelves is greater than or equal to the preset threshold, all shelves are symmetrically divided into two groups, and the origin of the coordinates is set at the symmetrical center point between the two groups of shelves.

6. The method for moving and positioning a warehouse robot according to claim 1, characterized in that, The gripper is slidably mounted on the robot body via a lifting mechanism; After the control module controls the robot body to move to the shelf coordinates where the target product is located, it also includes a Z-axis positioning step: Obtain the height coordinate value from the product coordinates, the height coordinate value corresponding to the shelf height position of the target product on the shelf; Based on the height coordinates, the control module drives the lifting mechanism to raise or lower the gripper to the target floor height to perform the retrieval operation.

7. A mobile positioning system for a warehouse management robot, applied to the mobile positioning method for a warehouse management robot according to any one of claims 1-6, characterized in that, include: The robot itself; Drive wheel; It is installed on the bottom surface of the robot body to drive the robot body to move; The cable reel has a fixed end that is fixed to the charging port and defined as the origin of the coordinate system, and a pull cable at the movable end that is connected to the robot body. The cable reel integrates a length encoder for detecting the extension length of the pull cable and an angle encoder for detecting the deflection angle of the pull cable. A gripper, which is mounted on the robot body, is used to grip goods; Lifting module; It is installed on the robot body to drive the gripper to move up and down on the robot body; The database stores product IDs, shelf coordinates bound to the product IDs, product coordinates, and automatic packaging machine coordinates. The shelf coordinates and product coordinates are both calibrated with reference to the coordinate origin. The control module is communicatively connected to the drive wheel, the length encoder, the angle encoder, the lifting module, and the database.

8. The mobile positioning system for a warehouse management robot according to claim 7, characterized in that, The control module is also used to calculate the current position of the robot body relative to the coordinate origin in real time based on the change in the length of the pull wire fed back by the length encoder and the change in the angle fed back by the angle encoder during the movement of the robot body, and to perform position correction when the robot body senses a preset marker point on the ground.

9. The mobile positioning system for a warehouse management robot according to claim 7, characterized in that, The cable of the reel also serves as the power supply cable for the robot body and the physical ranging baseline. The control module uses the real-time extension length of the pull wire as the basis for distance measurement, thus shielding the impact of external wireless signal interference on positioning accuracy.

10. The mobile positioning system for a warehouse management robot according to claim 7, characterized in that, The location of the coordinate origin within the warehouse plane is determined based on the total number of shelves: When the total number of shelves is less than a preset threshold, the origin of the coordinate system is set at one corner of the outermost shelf. When the total number of shelves is greater than or equal to the preset threshold, all shelves are symmetrically divided into two groups, and the origin of the coordinates is set at the symmetrical center point between the two groups of shelves.

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