AGV positioning correction method and system

Abstract

The invention discloses an AGV positioning correction method and system, and the method comprises the following steps: building a geographic coordinate system according to a preset fixed geographic standard block, and deploying a positioning block and a positioning identifier; constructing a sub-coordinate system according to the coordinate of any positioning block in the geographic coordinate system, and binding the working point coordinate with the sub-coordinate system; the AGV is arranged at the original point of the geographic coordinate system, the AGV is made to run to any positioning block, and the difference between the actual geographic coordinate of the AGV at the positioning block and the geographic coordinate of the positioning block serves as the accessory deviation; the difference between the sub-coordinates of the working point after replacement and the sub-coordinates of the working point before replacement is used as the deviation of the working point; and calibrating the AGV path according to the accessory deviation and the working point deviation. According to the method, the AGV path is compensated through the accessory deviation and the working point deviation, the driving precision of the AGV is improved, the accessory deviation and the working point deviation are iteratively optimized until errors are converged, and the driving precision of the AGV is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of AGV guided vehicles, and in particular to an AGV positioning and correction method and system. Background Art

[0002] AGV stands for Automated Guided Vehicle, a type of automated transport vehicle that relies on various positioning and navigation technologies and does not require a human operator. AGVs are automated devices equipped with electromagnetic or optical automatic guidance systems, capable of traveling along a prescribed path and equipped with safety features and various transfer functions. AGVs are characterized by wheeled mobility, offering advantages over walking, crawling, or other non-wheeled mobile robots, such as speed, high efficiency, simple structure, strong controllability, and improved safety.

[0003] The current mainstream positioning and identification navigation solution relies on ground tags to provide absolute coordinates. Although it is low-cost, it has significant bottlenecks:

[0004] 1. High maintenance costs associated with environmental changes. When adjusting the production line layout or relocating a workstation, old positioning markers must be removed and re-laid for calibration. The AGV must then rescan the entire line to collect the new coordinates. For example, on a 100-meter production line, the traditional process takes over four hours, resulting in tens of thousands of yuan in downtime losses.

[0005] 2. Part replacements cause systematic deviations. The origin of the AGV's coordinate system is located inside the device. When replacing accessories like drive wheels and cameras, the actual location of this origin shifts, invalidating the coordinates of all workpoints. To maintain data consistency, the AGV must return to the global origin, retraverse the entire path, and rescan the barcode to record the coordinates. This is extremely inefficient in long-distance, multi-target scenarios. Summary of the Invention

[0006] In view of the above-mentioned deficiencies in the existing technology, the technical problem to be solved by the present invention is: to propose an AGV positioning correction method and system, which can compensate the AGV path through accessory deviation and working point deviation, thereby improving the driving accuracy of the AGV, and further improve the driving accuracy of the AGV by iteratively optimizing the accessory deviation and working point deviation until the error converges.

[0007] A technical solution adopted by the present invention is to provide an AGV positioning correction method, comprising the following steps:

[0008] S1: Establish a geographic coordinate system based on the preset fixed geographic standard block, and deploy positioning blocks and positioning markers;

[0009] S2: Construct a sub-coordinate system according to the coordinates of any positioning block in the geographic coordinate system, and bind the coordinates of the working point to the sub-coordinate system;

[0010] S3: placing the AGV at the origin of the geographic coordinate system, driving the AGV to any positioning block, and taking the difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block as the accessory deviation;

[0011] S4: taking the difference between the sub-coordinate of the working point after replacement and the sub-coordinate of the working point before replacement as the working point deviation;

[0012] S5: Calibrate the AGV path based on the accessory deviation and working point deviation.

[0013] Furthermore, the method further comprises:

[0014] S6: Repeat steps S3-S5 to calculate the error between the actual path and the calibrated path during AGV operation, and dynamically adjust the accessory deviation and working point deviation until the error is less than the preset threshold.

[0015] Furthermore, the step S1 includes the following sub-steps:

[0016] S11: Setting a fixed geographic standard block and using the fixed geographic standard block as the origin to construct a geographic coordinate system;

[0017] S12: Deploy positioning blocks at key points on the AGV path, and deploy positioning markers at each work point and positioning block.

[0018] Furthermore, the step S2 includes the following sub-steps:

[0019] S21: Select any positioning block, use the coordinates of the positioning block in the geographic coordinate system as the origin, and construct a sub-coordinate system;

[0020] S22: Associating the coordinates of each working point with the sub-coordinate system:

[0021]

[0022] in, Indicates the x coordinate of the working point in the geographic coordinate system, Indicates the y coordinate in the geographic coordinate system, cos Q bθ Indicates the cosine value of the positioning block's orientation angle, sin Q bθ Indicates the sine value of the positioning block's orientation angle. Indicates the x-coordinate of the working point in the sub-coordinate system, Indicates the y coordinate of the working point in the sub-coordinate system, Q bx Indicates the x coordinate of the positioning block in the geographic coordinate system, Q by Indicates the y coordinate of the positioning block in the geographic coordinate system.

[0023] Furthermore, the step S3 further includes the following sub-steps:

[0024] S31: Place the AGV at the origin of the geographic coordinate system, use the coordinates of any positioning block in the geographic coordinate system as the deviation value, and drive the AGV to the accessory calibration point according to the deviation value;

[0025] S32: Obtain the actual geographic coordinates of the AGV at the accessory calibration point;

[0026] S33: The difference between the coordinates of the positioning block corresponding to the accessory calibration point in the geographic coordinate system and the actual geographic coordinates of the AGV at the accessory calibration point is taken as the accessory deviation:

[0027] Δx p =P ax -Q bx

[0028] Δy p =P ay -Q by

[0029] Where Δx p Indicates the x-axis accessory deviation, Δy p Indicates the y-axis accessory deviation, P ax Indicates the actual geographic x coordinate of the AGV at the accessory calibration point, P ay Indicates the actual geographic y coordinate of the AGV at the accessory calibration point, Q bx Indicates the geographic x coordinate of the corresponding positioning block, Q by Indicates the geographic y coordinate of the corresponding positioning block.

[0030] Furthermore, the step S4 further includes the following sub-steps:

[0031] S41: Bind the work point to be replaced to the nearest positioning block, and obtain the sub-coordinates of the work point in the sub-coordinate system with the positioning block as the origin as the sub-coordinates before replacement;

[0032] S42: replacing the working point, and obtaining the sub-coordinates of the replaced working point in the sub-coordinate system with the positioning block as the origin, as the replaced sub-coordinates;

[0033] S43: The difference between the sub-coordinates before and after the replacement is taken as the working point deviation:

[0034]

[0035]

[0036] Where Δx w Indicates the x offset of the working point in the sub-coordinate system, Δy wIndicates the y offset of the working point in the sub-coordinate system, Indicates the x coordinate of the working point in the sub-coordinate system after the change. Indicates the y coordinate of the working point in the sub-coordinate system after the working point is changed.

[0037] Furthermore, the step S5 includes the following sub-steps:

[0038] S51: Compensate the accessory deviation to all path points on the initial path of the AGV;

[0039] S52: Compensate the working point deviation to the path point corresponding to the replaced working point in the AGV initial path.

[0040] Furthermore, the step S6 includes the following sub-steps:

[0041] S61: Make the AGV execute the calibrated path and calculate the error between the actual AGV path and the calibrated path:

[0042]

[0043] in, Represents the global average error, T represents the total path time, k represents the iteration time, represents the actual x-coordinate at time t, represents the actual y coordinate at time t, x t (t) represents the theoretical x coordinate at time t, y t (t) represents the theoretical y coordinate at time t, represents the operating point error, t w represents the arrival time of the working point, Indicates t w The actual x coordinate of the working point reached by the AGV at the moment, Indicates t w The actual y coordinate of the working point reached by the AGV at time t;

[0044] S62: With the error not exceeding the preset threshold as the convergence condition, repeat steps S3-S5 to iterate the accessory deviation and working point deviation:

[0045]

[0046] Wherein, L represents the preset threshold;

[0047] S63: Update the accessory deviation and working point deviation:

[0048]

[0049] in, represents the x-axis fitting deviation of the k+1th iteration, represents the y-axis fitting deviation of the k+1th iteration, k p represents the accessory bias learning rate, represents the x-axis working point deviation of the k+1th iteration, represents the y-axis working point deviation of the k+1th iteration, k w represents the operating point deviation learning rate.

[0050] To solve the above technical problems, the second technical solution adopted by the present invention is to provide an AGV positioning and correction system, which includes the following modules:

[0051] Initialization module, used to establish geographic coordinate system based on preset fixed geographic standard blocks, and deploy positioning blocks and positioning markers;

[0052] A coordinate association module, configured to construct a sub-coordinate system according to the coordinates of any positioning block in the geographic coordinate system, and bind the coordinates of the working point to the sub-coordinate system;

[0053] An accessory deviation calculation module is used to place the AGV at the origin of the geographic coordinate system, drive the AGV to any positioning block, and use the difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block as the accessory deviation;

[0054] a working point deviation calculation module, configured to use the difference between the sub-coordinate of the working point after replacement and the sub-coordinate of the working point before replacement as the working point deviation;

[0055] The calibration module is used to calibrate the AGV path based on the accessory deviation and working point deviation.

[0056] Furthermore, the system also includes:

[0057] The accuracy verification module is used to repeat the steps of the accessory deviation calculation module, the working point deviation calculation module and the calibration module to calculate the error between the actual path and the calibration path when the AGV is running, and dynamically adjust the accessory deviation and the working point deviation until the error is less than a preset threshold.

[0058] The AGV positioning and correction method and system of the present invention have at least the following beneficial effects: 1. A geographic coordinate system is established by fixing the geographic standard block, thereby ensuring zero point accuracy through physical contact between the AGV and the geographic standard block; 2. A sub-coordinate system is constructed through the positioning block, thereby associating the work point coordinates into the sub-coordinate system, realizing dynamic association between the work point coordinates and the sub-coordinate system, and then when the work point needs to adjust its position, it is only necessary to calculate its offset in the sub-coordinate system to obtain the work point offset; 3. The AGV path is compensated by the accessory deviation and the working point deviation, thereby improving the driving accuracy of the AGV; 4. The driving accuracy of the AGV is further improved by iteratively optimizing the accessory deviation and the working point deviation until the error converges. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0060] Figure 1 This is a flowchart of an AGV positioning and correction method of the present invention.

[0061] Figure 2 For the present invention Figure 1 Sub-flowchart of step S1 in

[15] .

[0062] Figure 3 For the present invention Figure 1 Sub-flowchart of step S2 in

[15] .

[0063] Figure 4 For the present invention Figure 1 Sub-flowchart of step S3 in

[15] .

[0064] Figure 5 For the present invention Figure 1 Sub-flowchart of step S4 in

[15] .

[0065] Figure 6 For the present invention Figure 1 Sub-flowchart of step S5 in

[15] .

[0066] Figure 7 For the present invention Figure 1 Sub-flowchart of step S6 in

[15] .

[0067] Figure 8 This is a structural block diagram of an embodiment of an AGV positioning and correction system of the present invention. DETAILED DESCRIPTION

[0068] The present invention will be further described below with reference to the accompanying drawings.

[0069] See also Figure 1, is a flow chart of an embodiment of the AGV positioning and correction method of the present invention. This embodiment may specifically include the following steps:

[0070] S1: Establish a geographic coordinate system based on the preset fixed geographic standard block, and deploy positioning blocks and positioning markers.

[0071] Specifically, the construction of the geographic coordinate system in this solution can be achieved by setting fixed geographic standard blocks or pre-buried foundation piles at preset fixed points, and using the fixed geographic standard blocks or foundation piles as the origin to construct the geographic coordinate system. The AGV can initialize its path position through physical contact with the fixed geographic standard blocks or foundation piles. The positioning blocks can be deployed at key points on the path (such as corners, or near work points that need to be updated frequently), and there can be multiple positioning blocks. It should be noted that once the positioning blocks are deployed, their positions are fixed and do not change. The positioning identifier can be deployed at each work point and positioning block, which stores the coordinate values ​​of the corresponding positioning blocks and work points.

[0072] See also Figure 2 , this step S1 may include the following sub-steps:

[0073] S11: Set a fixed geographic standard block and use it as the origin to construct a geographic coordinate system. In this step, the geographic coordinate system can be constructed by setting a fixed geographic standard block at a preset fixed point, or pre-buried foundation piles, and using the fixed geographic standard block or foundation pile as the origin to construct the geographic coordinate system. The AGV can initialize its path position through physical contact with the fixed geographic standard block or foundation pile, thereby eliminating the initial posture deviation and ensuring the initial accuracy of the AGV's travel.

[0074] S12: Deploy positioning blocks at key points on the AGV path, and deploy positioning identifiers at each work point and positioning block. It is worth mentioning that the work point is the operating point that the AGV needs to reach in the path, which may include a transport point, an assembly point, etc. This step can be deployed at key points on the path (such as corners, or near work points that need to be frequently updated), and the number of such points can be multiple. It should be noted that once the positioning block is deployed, its position is fixed and does not change. At this time, by recording the geographic coordinates of the positioning block, a global mapping of the positioning block and the geographic coordinates can be constructed. The positioning identifier can be deployed at each work point and positioning block, which associates the geographic coordinates of the corresponding positioning block and the sub-coordinates of the work point, realizing the dynamic binding of the work point and the positioning block. The coupling degree is reduced through coordinate hierarchical management. The AGV can obtain the geographic coordinates of the positioning block or the sub-coordinates of the work point associated with the positioning identifier through visual scanning. In this field, the commonly used QR code navigation can be regarded as one of the implementation methods of the positioning identifier in this solution.

[0075] S2: Construct a sub-coordinate system based on the coordinates of any positioning block in the geographic coordinate system, and bind the work point coordinates to the sub-coordinate system. In step S2, a sub-coordinate system is constructed based on the geographic coordinates of any positioning block as the origin. The principle for selecting positioning blocks is to select the positioning block closest to the work point that requires frequent updates as the sub-coordinate system origin. This reduces the calculation error of the work point deviation when dynamically associating the work point with the sub-coordinate system.

[0076] In some embodiments, see Figure 3 , this step S2 may include the following sub-steps:

[0077] S21: Select any positioning block, use the coordinates of the positioning block in the geographic coordinate system as the origin, and construct a sub-coordinate system.

[0078] S22: Associating the coordinates of each working point with the sub-coordinate system:

[0079]

[0080] in, Indicates the x coordinate of the working point in the geographic coordinate system, Indicates the y coordinate in the geographic coordinate system, cos Q bθ Indicates the cosine value of the positioning block's orientation angle, sin Q bθ Indicates the sine value of the positioning block's orientation angle. Indicates the x-coordinate of the working point in the sub-coordinate system, Indicates the y coordinate of the working point in the sub-coordinate system, Q bx Indicates the x coordinate of the positioning block in the geographic coordinate system, Q by Indicates the y coordinate of the positioning block in the geographic coordinate system.

[0081] Specifically, the above steps S21 and S22 provide a specific coordinate transformation rule between the working point and the sub-coordinate system, thereby facilitating the subsequent calculation of the working point deviation.

[0082] S3: Place the AGV at the origin of the geographic coordinate system and drive it to any positioning block. The difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block is used as the accessory deviation. When the AGV's accessories are replaced, the position of its sensor relative to the origin of the geographic coordinate system may shift. Therefore, after the AGV's accessories are replaced, it is necessary to first calculate the AGV accessory deviation and compensate the AGV accessory deviation to all points in the path to ensure driving accuracy. This AGV accessory deviation can be calculated by the difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block.

[0083] See also Figure 4, this step S3 may include the following sub-steps:

[0084] S31: Place the AGV at the origin of the geographic coordinate system, use the coordinates of any positioning block in the geographic coordinate system as the deviation value, and drive the AGV to the accessory calibration point according to the deviation value;

[0085] S32: Obtain the actual geographic coordinates of the AGV at the accessory calibration point;

[0086] S33: The difference between the coordinates of the positioning block corresponding to the accessory calibration point in the geographic coordinate system and the actual geographic coordinates of the AGV at the accessory calibration point is taken as the accessory deviation:

[0087] Δx p =P ax -Q bx ;

[0088] Δy p =P ay -Q by ;

[0089] Where Δx p Indicates the x-axis accessory deviation, Δy p Indicates the y-axis accessory deviation, P ax Indicates the actual geographic x coordinate of the AGV at the accessory calibration point, P ay Indicates the actual geographic y coordinate of the AGV at the accessory calibration point, Q bx Indicates the geographic x coordinate of the corresponding positioning block, Q by Indicates the geographic y coordinate of the corresponding positioning block.

[0090] Specifically, the above S31-S33 scheme is the specific calculation method of the accessory deviation. It should be noted that the above calculation only gives the calculation of the x-axis and y-axis coordinate deviations. When the z-axis coordinate of the AGV also deviates, its calculation method is the same as the calculation of the x-axis and y-axis coordinate deviations.

[0091] S4: The difference between the sub-coordinates of the work point after the change and the sub-coordinates before the change is used as the work point deviation. The position of the work point has a direct impact on the AGV's travel path, which directly determines the AGV's formal path. Therefore, after the position of certain work points is changed, the AGV path points corresponding to these work points need to be compensated. The compensation value is the work point deviation, which can be calculated by the difference between the sub-coordinates of the work point after the change and the sub-coordinates of the work point before the change.

[0092] In some embodiments, see Figure 5 , this step S4 may further include the following sub-steps:

[0093] S41: Bind the work point to be replaced to the nearest positioning block, and obtain the sub-coordinates of the work point in the sub-coordinate system with the positioning block as the origin as the sub-coordinates before replacement;

[0094] S42: replacing the working point, and obtaining the sub-coordinates of the replaced working point in the sub-coordinate system with the positioning block as the origin, as the replaced sub-coordinates;

[0095] S43: The difference between the sub-coordinates before and after the replacement is taken as the working point deviation:

[0096]

[0097] Where Δx w Indicates the x offset of the working point in the sub-coordinate system, Δy w Indicates the y offset of the working point in the sub-coordinate system, Indicates the x coordinate of the working point in the sub-coordinate system after the change. Indicates the y coordinate of the working point in the sub-coordinate system after the working point is changed.

[0098] Specifically, the above steps S41-S43 provide a specific calculation process for the work point deviation. It should be noted that in step S41, the positioning block closest to the work point to be replaced is selected as the sub-coordinate system. That is, when multiple work points need to be relocated, the positioning block closest to each work point to be replaced can be selected as the sub-coordinate system origin, and the difference in sub-coordinates before and after the replacement of each work point to be replaced is calculated and used as the work point deviation of the corresponding work point. Similarly, the above calculation process only provides the calculation of the x-axis and y-axis deviations of the work point, and the calculation of the z-axis deviation is similar to the calculation of the x-axis and y-axis deviations.

[0099] S5: Calibrate the AGV path based on accessory deviation and workpoint deviation. Steps S3 and S4 above calculated accessory deviation and workpoint deviation, respectively. Step S5 compensates the AGV path using these deviations, allowing for repositioning and correction of the AGV path after accessory replacement and / or workpoint position changes.

[0100] In some embodiments, see Figure 6 , this step S5 may further include the following sub-steps:

[0101] S51: Compensate the accessory deviation to all path points in the AGV's initial path; since the relative position of the AGV to each working point may change after the accessories are replaced, the correction of the accessory deviation needs to be performed by compensating the accessory deviation to all path points in the AGV's initial path.

[0102] S52: Compensate the work point deviation to the path point in the AGV's initial path that corresponds to the replaced work point. Unlike accessory deviation, when only part of the work point needs to be replaced, the work point deviation must be compensated to the path point in the AGV's initial path that corresponds to the replaced work point, thereby ensuring the accuracy of the AGV's compensation path.

[0103] S6: Repeat steps S3-S5 to calculate the error between the actual path and the calibrated path during operation, and dynamically adjust the accessory deviation and workpoint deviation until the error is less than a preset threshold. To further reduce compensation error and improve compensation accuracy, this step also dynamically adjusts the accessory deviation and workpoint deviation by repeating steps S3-S5 above. With the goal of reducing the error below the preset threshold, the accessory deviation and workpoint deviation are continuously updated, bringing the AGV's actual driving path closer to the theoretical path, further reducing the error and improving the AGV's path accuracy.

[0104] In some embodiments, see Figure 7 , this step S6 may further include the following sub-steps:

[0105] S61: Make the AGV execute the calibrated path and calculate the error between the actual AGV path and the calibrated path:

[0106]

[0107] in, Represents the global average error, T represents the total path time, k represents the iteration time, represents the actual x-coordinate at time t, represents the actual y coordinate at time t, x t (t) represents the theoretical x coordinate at time t, y t (t) represents the theoretical y coordinate at time t, represents the operating point error, t w represents the arrival time of the working point, Indicates t w The actual x coordinate of the working point reached by the AGV at the moment, Indicates t w The actual y coordinate of the workpoint reached by the AGV at time t; the two equations in step S61 are used to calculate the global average error and the workpoint error. This separation of system error and local error enables subsequent global optimization and local convergence. It is important to note that this solution does not provide a specific method for monitoring the AGV's actual path. However, existing multi-sensor technology can ensure that the AGV can collect real-time temporal and spatial distribution data of error.

[0108] S62: With the error not exceeding the preset threshold as the convergence condition, repeat steps S3-S5 to iterate the accessory deviation and working point deviation:

[0109]

[0110] Wherein, L represents a preset threshold; in step S62, the error iteration is determined by the preset threshold L. It should be noted that the preset threshold L can be adaptively set according to the actual accuracy requirements and its value can be between 0.01 mm and 0.2 mm. In addition, the number of iterations k can also be set according to actual requirements.

[0111] S63: Update the accessory deviation and working point deviation:

[0112]

[0113] in, represents the x-axis fitting deviation of the k+1th iteration, represents the y-axis fitting deviation of the k+1th iteration, k p represents the accessory bias learning rate, represents the x-axis working point deviation of the k+1th iteration, represents the y-axis working point deviation of the k+1th iteration, k w Represents the working point deviation learning rate. Step S63 is the specific iterative calculation process for the accessory deviation and working point deviation. When the error converges to meet the preset threshold, the final accessory deviation and working point deviation are recorded. At this time, the final accessory deviation is used to compensate for each path point in the AGV's previous iterative path. At the same time, the final working point deviation is used to compensate for the path point in the AGV's previous iterative path corresponding to the changed working point to obtain the final AGV path, at which point the AGV positioning correction is completed.

[0114] See also Figure 8 , is a structural block diagram of an embodiment of an AGV positioning and correction system of the present invention. An AGV positioning and correction system of this embodiment is used to implement the AGV positioning and correction method described in the above embodiment. Specifically, the AGV positioning and correction system of this embodiment includes an initialization module 100, a coordinate association module 200, an accessory deviation calculation module 300, a work point deviation calculation module 400, and a calibration module 500. Among them:

[0115] Initialization module 100, used to establish a geographic coordinate system based on a preset fixed geographic standard block, and deploy positioning blocks and positioning markers;

[0116] A coordinate association module 200 is used to construct a sub-coordinate system according to the coordinates of any positioning block in the geographic coordinate system, and bind the coordinates of the working point to the sub-coordinate system;

[0117] The accessory deviation calculation module 300 is used to place the AGV at the origin of the geographic coordinate system, drive the AGV to any positioning block, and use the difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block as the accessory deviation;

[0118] A working point deviation calculation module 400 is configured to use the difference between the sub-coordinates of the working point after replacement and the sub-coordinates of the working point before replacement as the working point deviation;

[0119] The calibration module 500 is used to calibrate the AGV path according to the component deviation and the working point deviation.

[0120] In some embodiments, the AGV positioning correction system may further include:

[0121] The accuracy verification module 600 is used to repeat the steps of the accessory deviation calculation module, the working point deviation calculation module and the calibration module to calculate the error between the actual path and the calibrated path when the AGV is running, and dynamically adjust the accessory deviation and the working point deviation until the error is less than a preset threshold.

[0122] The present invention establishes a geographic coordinate system by fixing geographic standard blocks, thereby ensuring zero point accuracy through physical contact between the AGV and the geographic standard blocks; it can also construct a sub-coordinate system through positioning blocks, thereby associating the work point coordinates into the sub-coordinate system, realizing dynamic association between the work point coordinates and the sub-coordinate system, and then, when the work point needs to adjust its position, it only needs to calculate its offset in the sub-coordinate system to obtain the work point offset; and the AGV path is compensated by the accessory deviation and the work point deviation, thereby improving the driving accuracy of the AGV; at the same time, the accessory deviation and the work point deviation are iteratively optimized until the error converges, thereby further improving the driving accuracy of the AGV.

[0123] The above description merely expresses the preferred embodiments of the present invention, and its description is relatively specific and detailed, but it should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art may make a number of variations and improvements without departing from the concept of the present invention, and these variations and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent of the present invention shall be based on the appended claims.

Claims

1. An AGV positioning correction method, characterized in that: The following steps are involved: S1: Establish a geographic coordinate system based on the preset fixed geographic standard block, and deploy positioning blocks and positioning markers; S2: Construct a sub-coordinate system according to the coordinates of any positioning block in the geographic coordinate system, and bind the coordinates of the working point to the sub-coordinate system; S3: placing the AGV at the origin of the geographic coordinate system, driving the AGV to any positioning block, and taking the difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block as the accessory deviation; S4: taking the difference between the sub-coordinate of the working point after replacement and the sub-coordinate of the working point before replacement as the working point deviation; S5: Calibrate the AGV path based on the accessory deviation and working point deviation.

2. The AGV positioning correction method according to claim 1, characterized in that: The method further includes: S6: Repeat steps S3-S5 to calculate the error between the actual path and the calibrated path during AGV operation, and dynamically adjust the accessory deviation and working point deviation until the error is less than the preset threshold.

3. The AGV positioning correction method according to claim 1, characterized in that: The S1 step includes the following sub-steps: S11: Setting a fixed geographic standard block and using the fixed geographic standard block as the origin to construct a geographic coordinate system; S12: Deploy positioning blocks at key points on the AGV path, and deploy positioning markers at each work point and positioning block.

4. The AGV positioning correction method according to claim 1, characterized in that: The S2 step includes the following sub-steps: S21: Select any positioning block, use the coordinates of the positioning block in the geographic coordinate system as the origin, and construct a sub-coordinate system; S22: Associating the coordinates of each working point with the sub-coordinate system: in, Indicates the x coordinate of the working point in the geographic coordinate system, Indicates the y coordinate in the geographic coordinate system, cosQ bθ Indicates the cosine value of the positioning block's orientation angle, sinQ bθ Indicates the sine value of the positioning block's orientation angle. Indicates the x-coordinate of the working point in the sub-coordinate system, Indicates the y coordinate of the working point in the sub-coordinate system, Q bx Indicates the x coordinate of the positioning block in the geographic coordinate system, Q by Indicates the y coordinate of the positioning block in the geographic coordinate system.

5. The AGV positioning correction method according to claim 1, characterized in that: The S3 step further includes the following sub-steps: S31: Place the AGV at the origin of the geographic coordinate system, use the coordinates of any positioning block in the geographic coordinate system as the deviation value, and drive the AGV to the accessory calibration point according to the deviation value; S32: Obtain the actual geographic coordinates of the AGV at the accessory calibration point; S33: The difference between the coordinates of the positioning block corresponding to the accessory calibration point in the geographic coordinate system and the actual geographic coordinates of the AGV at the accessory calibration point is taken as the accessory deviation: Δx p =P ax -Q bx ; Δy p =P ay -Q by ; Where Δx p Indicates the x-axis accessory deviation, Δy p Indicates the y-axis accessory deviation, P ax Indicates the actual geographic x coordinate of the AGV at the accessory calibration point, P ay Indicates the actual geographic y coordinate of the AGV at the accessory calibration point, Q bx Indicates the geographic x coordinate of the corresponding positioning block, Q by Indicates the geographic y coordinate of the corresponding positioning block.

6. The AGV positioning correction method according to claim 1, characterized in that: The S4 step further includes the following sub-steps: S41: Bind the work point to be replaced to the nearest positioning block, and obtain the sub-coordinates of the work point in the sub-coordinate system with the positioning block as the origin as the sub-coordinates before replacement; S42: replacing the working point, and obtaining the sub-coordinates of the replaced working point in the sub-coordinate system with the positioning block as the origin, as the replaced sub-coordinates; S43: The difference between the sub-coordinates before and after the replacement is taken as the working point deviation: Where Δx w Indicates the x offset of the working point in the sub-coordinate system, Δy w Indicates the y offset of the working point in the sub-coordinate system, Indicates the x coordinate of the working point in the sub-coordinate system after the change. Indicates the y coordinate of the working point in the sub-coordinate system after the working point is changed.

7. The AGV positioning correction method according to claim 1, characterized in that: The step S5 includes the following sub-steps: S51: Compensate the accessory deviation to all path points on the initial path of the AGV; S52: Compensate the working point deviation to the path point corresponding to the replaced working point in the AGV initial path.

8. The AGV positioning correction method according to claim 2, characterized in that: The step S6 includes the following sub-steps: S61: Make the AGV execute the calibrated path and calculate the error between the actual AGV path and the calibrated path: in, Represents the global average error, T represents the total path time, k represents the iteration time, represents the actual x-coordinate at time t, represents the actual y coordinate at time t, x t (t) represents the theoretical x coordinate at time t, y t (t) represents the theoretical y coordinate at time t, represents the operating point error, t w represents the arrival time of the working point, Indicates t w The actual x coordinate of the working point reached by the AGV at the moment, Indicates t w The actual y coordinate of the working point reached by the AGV at time t; S62: With the error not exceeding the preset threshold as the convergence condition, repeat steps S3-S5 to iterate the accessory deviation and working point deviation: Wherein, L represents the preset threshold; S63: Update the accessory deviation and working point deviation: in, represents the x-axis fitting deviation of the k+1th iteration, represents the y-axis fitting deviation of the k+1th iteration, k p represents the accessory bias learning rate, represents the x-axis working point deviation of the k+1th iteration, represents the y-axis working point deviation of the k+1th iteration, k w represents the operating point deviation learning rate.

9. An AGV positioning and correction system, characterized in that: The system includes the following modules: Initialization module, used to establish geographic coordinate system based on preset fixed geographic standard blocks, and deploy positioning blocks and positioning markers; A coordinate association module, configured to construct a sub-coordinate system according to the coordinates of any positioning block in the geographic coordinate system, and bind the coordinates of the working point to the sub-coordinate system; An accessory deviation calculation module is used to place the AGV at the origin of the geographic coordinate system, drive the AGV to any positioning block, and use the difference between the actual geographic coordinates of the AGV at the positioning block and the geographic coordinates of the positioning block as the accessory deviation; a working point deviation calculation module, configured to use the difference between the sub-coordinate of the working point after replacement and the sub-coordinate of the working point before replacement as the working point deviation; The calibration module is used to calibrate the AGV path based on the accessory deviation and working point deviation.

10. The AGV positioning and correction system according to claim 9, characterized in that: The system also includes: The accuracy verification module is used to repeat the steps of the accessory deviation calculation module, the working point deviation calculation module and the calibration module to calculate the error between the actual path and the calibration path when the AGV is running, and dynamically adjust the accessory deviation and the working point deviation until the error is less than a preset threshold.

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