Automatic spraying method and system capable of adjusting spraying posture in self-adaptive mode

Abstract

The invention provides an automatic spraying method and system capable of adaptively adjusting spraying postures, and relates to the technical field of automatic construction, in particular to automatic spraying operation. The spraying method specifically comprises the steps that an unmanned aerial vehicle is controlled to execute stable flight tracking according to a preset global path waypoint; in the stable flight tracking process, synchronous data frames of the actual surface of a target are continuously collected through a five-point laser sensing array; calculating an attitude correction angle in real time based on the synchronous data frame; the two-axis holder is controlled to execute the attitude correction angle so as to adjust the spraying attitude of the spraying unit; calculating a gentle degree error in real time based on the synchronous data frame; the gentle degree error is compared with a preset gentle degree threshold value, and a spraying decision is made; when the gentle degree error is not larger than the gentle degree threshold value, it is judged that the actual surface is gentle, and one-time spraying is executed; and when the smoothness error is larger than the smoothness threshold value, it is judged that the actual surface is complex, and self-adaptive partition spraying is executed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automated construction technology, in particular to automated spraying operation. More specifically, the present application relates to an automated spraying method and system capable of self-adaptively adjusting the spraying posture, which can perceive the local geometry of the target surface in real time during the spraying process and self-adaptively adjust the spraying posture of the spraying unit, especially suitable for unmanned spraying operation on large-scale infrastructure with complex three-dimensional curved surface features, such as highway bridges, tunnels or large structural components. BACKGROUND

[0002] In the fields of maritime engineering, large equipment manufacturing and energy industry (such as wind turbine towers, large storage tanks), surface coating protection of large structural components is a key process to ensure the structural integrity and prolong the service life. Taking large ships as an example, the hull, such as the freeboard, the vicinity of the waterline and the bottom, is exposed to the high-salt and high-humidity marine corrosion environment for a long time, and at the same time faces the serious challenge of marine bio-attachment. Therefore, it is necessary to apply high-performance anti-corrosion and anti-fouling coatings to the hull regularly. These coating operations have very high quality requirements, and the uniformity of coating thickness and adhesion directly determine the maintenance cycle and operating cost of the ship.

[0003] Traditionally, the spraying operation of large ships, whether new or repaired, highly depends on manual work, supplemented by large-area scaffolding, aerial work platforms or baskets and other auxiliary equipment. This mode has inherent defects that are difficult to overcome. First, the safety risk is extremely high, and workers operate in a swaying environment on the dock or at sea, which is prone to safety accidents such as falling. Second, the operation efficiency is low, and the surface area of the ship is huge, and it takes a lot of time and labor cost to build and move the scaffolding covering the hull, especially the large-curvature areas such as the bow and stern. Third, the uniformity of the spraying quality is difficult to guarantee. Large ships, especially the bulbous bow at the bow and the area near the propeller at the stern, present a complex three-dimensional free curved surface (hyperboloid) morphology. When workers manually hold the spray gun, it is difficult to maintain a constant distance and vertical spraying angle between the spray gun and the work surface on such a large-scale and continuously changing surface.

[0004] In order to solve the above problems, automated spraying technology has been introduced into the field of shipbuilding and maintenance. Some early automation attempts, such as robot systems based on ground tracks or large gantries, have achieved certain results in spraying standard planar segments in shipyards. However, these large fixed or track-based robot systems have a great limitation in terms of operation range and flexibility. For a fully formed whole ship, especially in areas with complex morphology, high altitude or large span on the hull shell, these devices are too long to reach and cannot achieve effective coverage.

[0005] In recent years, as a kind of high-mobility aerial platform, unmanned aerial vehicle system provides a new technical path for solving the automatic operation of large complex surface. In theory, unmanned aerial vehicle can carry a spraying unit, and by virtue of its flexible flight ability in three-dimensional space, it can fly to any position that is difficult for artificial or traditional robots to reach, thereby greatly reducing the dependence on scaffolding, improving the safety of operation and shortening the construction period. However, it is still a serious technical bottleneck to transform unmanned aerial vehicle from a simple flight platform to a precise spraying executor when facing large complex curved surfaces. Most of the existing unmanned aerial vehicle spraying schemes are equipped with only a single-point distance measuring sensor, which is used to maintain a single distance between the unmanned aerial vehicle and the target surface. This single-point distance measuring logic can barely maintain the distance when facing a plane, but it is completely unable to meet the requirements of high-quality spraying when facing the complex surface of the bow and stern of a large ship with significant curvature and inclination changes. Single-point distance measurement cannot perceive the local geometry of the target surface, especially the local vertical direction. Non-vertical spraying (i.e. non-normal spraying) will cause the spraying fan to produce distortion and irregular coverage on the workpiece, thereby causing serious unevenness in the coating thickness, resulting in failure of protection in some areas, and causing sagging and cracking in some areas, while sharply increasing the rebound over-spraying of paint mist, causing a large amount of waste of paint and environmental pollution. SUMMARY

[0006] The present application provides an automatic spraying method for self-adaptive adjustment of spraying posture, the method comprising: controlling the unmanned aerial vehicle to perform stable flight tracking according to the preset global path waypoints; during the stable flight tracking, continuously collecting synchronous data frames of the actual surface of the target through a five-point laser sensor array; based on the synchronous data frames, calculating a posture correction angle in real time; controlling a two-axis gimbal to execute the posture correction angle to adjust the spraying posture of the spraying unit; based on the synchronous data frames, calculating a flatness error in real time; comparing the flatness error with a preset flatness threshold to make a spraying decision; when the flatness error is not greater than the flatness threshold, determining that the actual surface is flat, and performing one-time spraying; when the flatness error is greater than the flatness threshold, determining that the actual surface is complex, and performing adaptive partition spraying.

[0007] The five-point laser sensor array comprises four corner lasers and one center laser ; the synchronous data frames at moment are in the form of: wherein, are the distances measured by the four corner lasers at moment, is the distance measured by the center laser at The actual center distance measured at the moment.

[0008] The step of calculating the attitude correction angle in real time includes calculating the horizontal distance difference and the vertical distance difference .

[0009]

[0010] The step of calculating the attitude correction angle includes calculating the yaw correction angle and the pitch correction angle .

[0011] wherein, is the known horizontal width of the sensor array, is the known vertical height of the sensor array.

[0012] The step of calculating the flatness error in real time includes calculating the expected center distance . The step of calculating the flatness error . .

[0013] The step of performing one-time spraying includes activating the spraying unit; while the spraying unit remains open, the steps of stabilizing flight tracking, calculating and controlling, and calculating and comparing are performed in parallel and continuously to achieve coordinated spraying flight.

[0014] The step of dividing into multiple sub-regions in adaptive partition spraying includes: when the flatness error is greater than the flatness threshold , calculating the horizontal twist and the vertical twist .

[0015] Comparing and with the twist threshold to make a partition decision of horizontal two-partition, vertical two-partition, or four-quadrant partition.

[0016] The step of controlling the UAV to move and align the sub-regions in sequence includes: defining a sub-region center offset vector corresponding to the partition decision in the sensor array coordinate system ; obtaining the rotation matrix of the UAV body coordinate system relative to the sensor array coordinate system at the moment ; the sub-region center offset vector is rotated by a rotation matrix into a body offset vector; the current position of the UAV when it is hovering is determined and the body offset vector, the sub-region corresponding sub-region hovering point is calculated ; the UAV is controlled to move to the sub-region hovering point .

[0017] The step of performing spot spraying includes: activating the spraying unit for a preset spot spraying duration while the UAV is hovering ; based on the sub-region area and the nominal volumetric flow rate are calculated:

[0018] wherein, the target coating thickness, the number of sub-regions of the partition.

[0019] The step of controlling the two-axis gimbal to execute the attitude correction angle includes: setting the pitch axis control error and the yaw axis control error :

[0020] The control instruction, such as the control instruction of the pitch axis, is calculated using a PID control algorithm :

[0021] wherein, the gain coefficient of the pitch axis PID controller, the integral variable.

[0022] The application also provides an automatic spraying system that adjusts the spraying attitude, which includes: a central control module: controlling the UAV to perform stable flight tracking according to a preset global path waypoint; a collection module: continuously collecting synchronous data frames of the actual surface of the target through a five-point laser sensing array during stable flight tracking; an attitude settlement module: real-time solving an attitude correction angle based on the synchronous data frames; controlling the two-axis gimbal to execute the attitude correction angle to adjust the spraying attitude of the spraying unit; a decision module: real-time calculating a flatness error based on the synchronous data frames; comparing the flatness error with a preset flatness threshold to make a spraying decision; When the flatness error is not greater than the flatness threshold, it is determined that the actual surface is flat, and one-time spraying is performed; when the flatness error is greater than the flatness threshold, it is determined that the actual surface is complex, and adaptive partition spraying is performed.

[0023] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the above-mentioned automatic spraying method of adaptively adjusting the spraying posture.

[0024] A computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement the above-mentioned automatic spraying method of adaptively adjusting the spraying posture.

[0025] The automatic spraying method and system of adaptively adjusting the spraying posture provided by the present application aim to solve the fundamental contradiction between flight safety, operation efficiency and spraying quality when the existing unmanned aerial vehicle spraying system faces large complex three-dimensional curved surfaces such as large ship hulls. The flight platform stability and spraying posture accuracy are fundamentally decoupled, greatly improving the operation safety. In the prior art, if the unmanned aerial vehicle body posture is used to align the curved surface normal, the body inertia is large and the response is slow, which seriously interferes with the flight stability. The present application solves this problem through the separation design of global path flight and two-axis gimbal posture adjustment. In the present application, the flight control system (FCS) of the unmanned aerial vehicle is only responsible for one task: tracking a smooth global path with sufficient safety margin. The unmanned aerial vehicle body does not need to make high-frequency flight posture adjustment according to the local geometry of the target surface. This maximizes the flight stability and operation safety of the unmanned aerial vehicle in complex wind field environments such as shipyards.

[0026] On the dynamic reference of stable flight of the unmanned aerial vehicle platform, the present application independently calculates the local pitch and yaw angles of the current actual surface in real time through the rigidly fixed five-point laser sensing array, especially using the data of the four corner lasers. The calculation speed is much faster than the inertia of the unmanned aerial vehicle body. Subsequently, the angle deviation is executed at high speed by the two-axis gimbal servo controller, realizing independent and rapid compensation of the spraying unit spraying posture. This design ensures that the spraying direction of the spray gun can always be aligned with the normal of the ship body surface with large curvature change.

[0027] The local approximation plane assumption will fail when facing welds, stiffeners or sharp corners. The invention provides an independent check by the "center laser" in the "five-point" array. By comparing the expected center distance with the actual center distance, the flatness error is calculated in real time, thus quantifying the reliability of the solution. A decision is made based on this reliability. This check-before-decision mechanism ensures that the spraying operation is only performed when the pose alignment is confirmed to be reliable, fundamentally eliminating blind and erroneous spraying in areas of geometric mutation.

[0028] The system performs a coordinated spraying flight that maximizes efficiency by flying at high speed while maintaining normal alignment. When it determines that it has encountered complex geometry that results in an unreliable solution, instead of simply skipping, the system automatically switches to an adaptive zoned spraying strategy. By pausing, making zoned decisions, and processing sub-regions in a loop, it breaks down large, unreliable regions into small, checkable sub-regions. It re-executes the entire perception-solution-check cycle for each sub-region, and point spraying is also performed only when the normal pose is confirmed to be reliable. This quality-first recursive processing mechanism, combined with the safe exit function of the abnormal region log, makes the invention robust in handling extreme complex geometry while ensuring overall operation efficiency, achieving full-process automation and high-quality spraying. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 An adaptive spraying process diagram that adjusts the spraying pose. DETAILED DESCRIPTION

[0030] The specific embodiments of the present application will be described below with reference to specific examples. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the specification. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. The present application can also be implemented or applied by other different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0031] It is to be appreciated that various aspects of the embodiments described below are presented for illustration and that the described aspects are merely examples. Any feature, structure, or function described herein can be combined in any and all combinations with any other feature, structure, or function. It is further appreciated that the aspects described herein can be implemented in a wide variety of forms and that any particular feature or combination of features need not be implemented to benefit from the application. For example, an apparatus can be implemented using any number and combination of aspects described herein.

[0032] In addition, in the following description, specific details are given to provide thorough understanding of examples. However, one skilled in the relevant art will understand that the embodiments can be practiced without these specific details.

[0033] The present embodiment details the process of initializing the global path flight path in the automated spraying method of the present application. The purpose of initializing the global path flight path is to provide a safe, stable, and repeatable macroscopic reference trajectory for the entire automated spraying operation. Prior to initializing the global path flight path, the system pre-acquires a coarse 3D mesh model of the target to be sprayed and a set of pre-set spraying process parameters, including the reference operation distance and the nominal spraying coverage width. Based on the input 3D model and process parameters, the global flight path covering the entire target surface is calculated and generated offline, and the flight control system of the UAV loads and strictly executes the global path.

[0034] The specific steps of initializing the global path flight path include: S1: Offline generation of the global coverage path, i.e., in the preparation stage of the present application, the central controller or the background workstation first executes the global path generation algorithm.

[0035] S1.1: Input model and parameter definition, input the coarse three-dimensional mesh model of the target ship body . The model is a triangular mesh set composed of a large number of vertices and their normal vectors . At the same time, the key process parameters include: reference safety distance , the reference safety distance is a pre-set scalar value, representing the expected average distance between the UAV body and the nominal surface of the ship body. The effective coverage width of a single spraying, i.e., the spraying width , the spraying overlap rate .

[0036] S1.2: Generate offset surface and flight line spacing, in order to generate the flight path of the UAV, based on The offset surface is calculated. For any vertex on the surface , its corresponding offset vertex :

[0037] where is the unit normal vector at point, all constitute the offset surface , which is the surface where the ideal trajectory of the UAV flight lies.

[0038] Then, the lateral distance between two adjacent global paths, i.e., the airway distance is calculated:

[0039] S1.3: Generating coverage path waypoints, the present application adopts an arc-shaped path planning method to generate a continuous path curve on the surface. Along the path curve, sampling is performed at a fixed path step size, preferably, 1 meter, which discretizes the path curve into global path waypoints .

[0040] Each waypoint contains a three-dimensional position coordinate and a three-dimensional attitude direction . Here, is obtained from the coordinate of the sampling point on the surface, and the desired attitude of the waypoint is represented. In the present embodiment, in order to ensure the smoothness and stability of the UAV flight, the desired attitude is specifically set to make the Z-axis of the UAV point to the center of the earth or be parallel to the direction of gravity , and at the same time, make its X-axis (the body X-axis, i.e., the direction of the nose) align with the forward tangent direction of the point on the path .

[0041] S1.4: Dividing the spray area, the central controller divides the entire global path into continuous path segments, each path segment corresponding to a target spray area on the surface of the ship body (such as ).

[0042] Performing global path flight S2.1: Path loading and flight plan starting, after the UAV system starts, the central controller loads the global path waypoints generated in S1 to the flight control system (FCS) of the UAV.

[0043] S2.2: Stable flight tracking, after the operator issues the execution instruction, the FCS of the UAV starts to strictly perform the path tracking task.

[0044] In the present application, the flight control system (FCS) of the UAV is only responsible for one task, that is, tracking a global path that is smooth, continuous and has sufficient safety margin. The UAV does not need to adjust its own flight attitude according to the local complex changes of the hull surface. This greatly guarantees the flight stability and safety of the UAV as a heavy-duty work platform in common complex environments such as shipyards. At the same time, the global path ensures that the UAV platform always moves stably in a working area that is roughly parallel to the hull surface and has a controllable distance. This enables the subsequent spraying unit to perform high-speed and fine attitude compensation in a relatively stable and predictable dynamic reference within a small range, without having to deal with large swings of the UAV body. This lays the foundation for achieving high-quality normal alignment spraying.

[0045] Next, the present embodiment will elaborate the process of real-time surface sensing and attitude solving in the automatic spraying method of the present application. In order to obtain complex surface information, continuous data acquisition of the target is required. While the UAV body maintains stable flight, the local geometric data of the actual surface of the target ship body in front of the UAV in the spraying direction is obtained by using a five-point laser sensing array rigidly installed on a two-axis gimbal.

[0046] To achieve adaptive adjustment of the present application, the present embodiment adopts an integrated sensing and execution subsystem. The subsystem is installed on the UAV body, but its motion control is decoupled from the flight control system (FCS) of the UAV.

[0047] The integrated sensing and execution subsystem is composed of a two-axis gimbal , a spraying unit , and a five-point laser sensing array . The two-axis gimbal is a two-dimensional rotating mechanism driven by a servo, and its base is fixed to the UAV body. The two-axis gimbal can provide independent rotation in two degrees of freedom, namely pitch and yaw. The spraying unit includes a spray gun , and the spraying unit is rigidly installed on the movable execution end of the two-axis gimbal . The five-point laser sensing array includes four corner laser sensors ​) and a center point laser ( ), These represent the top left, top right, bottom left, and bottom right focal lasers, respectively. The four corner lasers are rigidly mounted on a two-axis gimbal. Above, the center point laser is installed in the spraying unit. spray gun Above, with the spray gun They have the same position and posture.

[0048] UAV body coordinate system It is installed on the drone's body. FCS controls... Position in the global coordinate system and posture .

[0049] Spraying unit coordinate system Located in the spraying unit Its origin is set at the spray gun. At the nozzle, The axis is defined as the theoretical center of the spray gun and the direction of the spray. With two-axis gimbal relative to the movement sports.

[0050] Sensor array coordinate system Laser with origin set at center point launch point Axis is defined as The direction of laser beam emission.

[0051] because and Rigidly fixed, therefore and The relative transformation matrix between It is a constant, known value. Furthermore, this invention ensures the direction of the central laser beam through precise installation and calibration. With respect to the direction of the spray gun Strict parallelism, that is .

[0052] Four corner lasers The laser beams are all with They are launched parallel to the axis. coordinate system plane (i.e.) The projected coordinates on the plane are defined as follows: coordinate: , coordinate: , coordinate: , coordinate: .in, Given the known horizontal width of the sensor array, The known vertical height of the sensor array. Indicates in Coordinates in a coordinate system.

[0053] Step S3.2: Continuous Data Acquisition Throughout the entire global path flight executed by the UAV's FCS, the central controller simultaneously performs high-frequency data acquisition using a five-point laser sensor array. A sampling frequency higher than the gimbal control frequency and the drone flight control frequency Continue working.

[0054] At any sampling time , array The five lasers in Simultaneously, they launch towards the actual surface of the target hull along their respective launch directions. A laser beam is emitted. The laser beam encounters... The reflection occurs behind the surface, and the receivers of each laser capture the echo and calculate their respective flight times, thus obtaining five independent distance measurements.

[0055] Central controller in The synchronization data frame is acquired and encapsulated at all times. :

[0056] in: , , as well as They represent , , , laser in The time measured along the edge Direction to The distance between surfaces.

[0057] The data acquisition process occurs when a drone is spraying data from a target area. Fly to the next one The process is executed continuously throughout, generating a continuous data stream, which is then transmitted to the central controller.

[0058] Used for planning global paths It is sparse and coarse, possibly lacking local details such as welds, deformations, or attachments. Through high-frequency... Sampling obtains the actual physical surface of the ship's hull. The millimeter-precision distance data provides a real-time data basis for pose adjustment, which is a prerequisite for high-quality spraying. The data acquisition and global path flight in the embodiment are performed in parallel. The UAV FCS does not care about local surface details, but is responsible for macroscopic stable flight; while the global path, but is responsible for measuring the local geometry in front of it. This decoupling design ensures that the UAV will not produce flight jitter due to trying to respond to surface details, greatly improving the safety and stability of the operation. The output is not a single distance value, but contains five spatially distributed synchronous distance points. This five-point data uniquely determines the central distance, pitch angle and yaw angle of the local surface faced by the coordinate system .

[0059] Next, the embodiment details the calculation of the local plane angle in the automatic spraying method of the application, real-time solving the local surface geometric information implied by the five-point data, specifically, calculating the angle deviation of the local normal direction of the actual surface faced by the sensor array coordinate system relative to the actual surface .

[0060] The central controller receives at each sampling time , and immediately calculates the horizontal angle deviation Step S4.1: Calculate the horizontal angle deviation, i.e. the yaw angle; The purpose of calculating the horizontal angle deviation is to calculate the relative angle of the actual surface in the X-Z plane of the coordinate system , which corresponds to the yaw angle that needs to be compensated by the two-axis gimbal .

[0061] S4.1.1 Calculate the average distance on the left and right: The controller extracts four corner point data. Calculate the average distance on the left side of the sensor array and the average distance on the right side of the sensor array .

[0062]

[0063]

[0064] S4.1.2 Calculate the horizontal distance difference: Calculate the horizontal distance difference Horizontal distance difference at time :

[0065] S4.1.3 Calculate yaw correction angle Value and known horizontal width of the sensing array form two sides of a right triangle. The central controller calculates the yaw correction angle necessary to achieve normal alignment using the arctangent function :

[0066] When , it indicates that the left side is further away and the right side is closer (e.g. facing a right convex curved surface of a ship hull), is positive, indicating that the gimbal needs to rotate to the right (positive yaw direction) to align with the normal.

[0067] S4.2: Calculate the angular deviation in the vertical direction, i.e. the pitch angle: The purpose of calculating the angular deviation in the vertical direction is to calculate the actual surface , in the relative inclination in the Y-Z plane of the coordinate system, which corresponds to the pitch angle that needs to be compensated by the two-axis gimbal. .

[0068] S4.2.1 Calculate the average distance up and down: The controller calculates the average distance of the sensing array upside ( ) and the average distance of the downside ( ). .

[0069]

[0070]

[0071] S4.2.2 Calculate the vertical distance difference: Calculate the vertical distance difference at time : :

[0072] S4.2.3 Calculate the pitch correction angle: Value and known vertical height of the sensing array form two sides of another right triangle. The central controller calculates the pitch correction angle necessary to achieve normal alignment using the arctangent function :

[0073] When is positive, it indicates that the gimbal needs to rotate upward (positive Pitch direction) to align with the normal line. When is negative, it indicates that the gimbal

[0074] needs to rotate downward (negative Pitch direction) to align with the normal line. S4.1: Calculate the angle deviation of the gimbal from the normal line. S4.2: Calculate the angle deviation of the gimbal from the normal line.

[0075] S4.3: Output the correction instruction The central controller outputs the and calculated in S4.1 and S4.2 as a binary correction instruction vector to the servo controller of the two-axis gimbal. S5.1: Set the control error The servo controller receives the correction angle calculated by S4 at time and directly defines it as the control error signal at the current time:

[0076] Yaw-axis control error : Pitch-axis control error :

[0077]

[0078] ​​​​​​

[0079] Step S5.2: Execute PID servo control; To achieve rapid and stable elimination of errors, the servo controller preferably adopts a dual-axis independent PID control algorithm.

[0080] Servo controller according to calculate The time should be applied to control output of the pitch axis motor :

[0081] in, This indicates the control command for the pitch axis motor, i.e., the torque command. , which are the proportional, integral, and derivative gain coefficients of the pitch-axis PID controller, respectively. This represents the integral variable.

[0082] At the same time, the servo controller according to calculate The time should be applied to Control output of yaw motor :

[0083] in, This indicates the control command for the yaw axis motor, i.e., the torque command. These are the proportional, integral, and derivative gain coefficients of the yaw axis PID controller, respectively.

[0084] Next, this embodiment details the calculation of the smoothness verification value in the automated spraying method of the present invention. The purpose is to perform real-time quantization verification of the local approximate plane assumption upon which the S4 algorithm relies, while the attitude correction angle is calculated using the four corner point data in S4 and the adjustment is performed in S5.

[0085] In the central controller Get it in real time While executing controls S4 and S5, the central controller simultaneously executes step S6: S6.1: Calculate the expected center distance S4 assumes a five-point laser sensor array. The actual surface being faced The region can be fitted by a local approximation plane. The purpose of S6.1 is to calculate, under this local approximation plane assumption, the region located at... Origin The theoretical distance value on the axis.

[0086] To obtain this theoretical value, the central controller adopts... time The arithmetic mean of the distances between the four corner points is used as the basis for calculation. Expected center distance at time :

[0087] S6.2: Obtain the actual center distance The central controller uses the same synchronization data frame as S6.1. In the middle, direct extraction from the center point laser Measured actual center distance .

[0088] S6.3: Calculate the smoothness error Central controller calculation and The absolute difference between them is obtained Time smoothness error :

[0089] Quantified the actual surface exist The vertical distance at the center point from the local approximate plane defined by the four corner points.

[0090] Step S4 itself cannot distinguish between a smooth ramp and a rough surface. In this embodiment, S6 introduces a center point. with corner average Independent comparisons solved this problem. In spraying applications on complex three-dimensional curved surfaces such as target ship hulls, when a five-point laser sensor array... Cross When there are welds, reinforcing ribs, or sharp corners on the surface, The local geometry deviates significantly from the local approximate plane assumption. In this case, the four corner points may fall within a smooth region, resulting in calculated... The performance is normal; however, the central laser... Located on a protrusion (leading to) ) or dent (causing) (above). This embodiment will immediately calculate a high... Value. This. The significance of the signal lies in the fact that it quantizes the output of S4. and And the reliability of the attitude adjustments performed by S5. A high Value means If the geometry of the area being addressed is too complex, attitude alignment based on a local approximate plane is unreliable, and painting should not be performed in this case. It is ensured that painting is only performed when the attitude alignment is confirmed as valid by S6 (i.e., ...). It is only executed when the surface is small enough, which fundamentally guarantees the coating quality of complex curved surfaces.

[0091] Next, this embodiment details the application of the verification result of S6 in the automated spraying method of the present invention. Time ( ) for the spraying unit It makes real-time adaptive decisions regarding starting and stopping.

[0092] Step S7: Spraying decision; S7.1: Define the smoothness threshold. During system initialization, a key parameter, namely the smoothness threshold, is preset. . As a scalar value, it represents The acceptable upper limit. The physical meaning of the value is in the five-point laser sensor array of Within the sampling area, the actual surface area that the system can tolerate The maximum vertical distance from the local approximate plane. In spray painting applications on the target hull, this value should be less than the typical height of welds or stiffeners to ensure sensitive detection of these complex geometric features that are unsuitable for spraying.

[0093] S7.2: Perform real-time comparisons and decisions; exist At any given moment, the central controller acquires the calculated... And immediately perform the following comparison: Scenario 1 (Smooth): If

[0094] Central controller determines: Current Facing The region is flat, and the local approximate plane assumption of S4 holds. Therefore, the attitude commands solved by S4 and the attitude alignment executed by S5 are reliable.

[0095] The central controller sets an internal status flag: .

[0096] Scenario 2 (Complex): If

[0097] Central controller determines: Current The area exhibits significant local bulges or depressions.

[0098] Therefore, the pose alignment based on the local approximated plane is unreliable.

[0099] The central controller sets an internal state flag: .

[0100] Step S8: Perform one-time spraying of the case 1 gentle region This step is only executed and maintained when S7 determines .

[0101] S8.1: Activate the spraying unit The central controller sends an open instruction to the execution valve of the spraying unit , so that the spray gun begins to spray paint.

[0102] S8.2: Perform cooperative spraying flight At the same time in the open state, the flight control system (FCS) of the UAV continues to strictly perform the stable flight tracking task, driving the UAV body to smoothly fly through the current target spraying region along the global path waypoint . The S3-S4-S5 closed loop continues to run. The PID controller continuously receives the error input of S4 and drives the two-axis gimbal to rotate in real time to compensate for the attitude deviation caused by the UAV flight and the change of the curved surface. Real-time verification continues to be performed. As long as the UAV always maintains , , , , the spraying instruction is always open.

[0103] S8.3: Region completion and transition When the flight control system (FCS) of the UAV detects that the UAV has flown to the global path waypoint at the end of the region, the central controller sends a close instruction .

[0104] Subsequently, the FCS controls the UAV to fly along the path to the next target spraying region , and the system begins to perceive the new region and prepares to repeat the calculation and decision-making process of S4-S7.

[0105] Next, this embodiment details the adaptive partition spraying process in the automatic spraying method of the application.

[0106] When it is determined that , the adaptive partition spraying is triggered immediately.

[0107] S9: Perform adaptive partition spraying; The purpose of adaptive partition spraying is to suspend the one-time spraying process of S8 when the dependent local approximate plane hypothesis fails, and instead perform a coarse-to-fine adaptive partition processing strategy. This strategy decomposes the current complex target spraying area into multiple smaller sub-areas, and independently performs a perception-solution-verification cycle (S3-S7) for each sub-area, in order to meet the local approximate plane hypothesis on a smaller scale, and ultimately achieve high-quality point spraying coverage of complex geometric surfaces.

[0108] Adaptive partition spraying includes: (1) complexity analysis and partition decision; (2) sub-area target point generation; (3) sub-area cycle processing (move-verify-point spray).

[0109] S9.1: Spray inhibition and global path suspension; At the moment , the central controller immediately sets to ensure that the spraying unit remains closed.

[0110] The central controller sends a pause and hover instruction to the unmanned aerial vehicle flight control system (FCS). The FCS immediately suspends the stable flight tracking task and controls the unmanned aerial vehicle to hover stably at the current position.

[0111] S9.2: Perform partition strategy decision The central controller analyzes the geometric causes leading to to decide which partition strategy to use, indicates the moment leading to , thereby triggering adaptive partition spraying.

[0112] Define complexity quantification indicators: Horizontal twist degree : Compare the vertical distance difference of the left side ( to ) with the vertical distance difference of the right side ( to ).

[0113]

[0114] Vertical twist degree : Compare the horizontal distance difference of the upper side ( to ) with the horizontal distance difference of the lower side ( to ).

[0115] ​​

[0116] Define twist threshold For determining whether there is significant twist or tilt within the coverage area.

[0117] IF AND

[0118] Then the surface has significant twist in the horizontal direction, e.g. across a vertical weld or vertical stiffener.

[0119] Partition decision : Horizontal two-partition (left , right ).

[0120] IF AND

[0121] Then the surface has significant twist in the vertical direction, e.g. across a horizontal weld.

[0122] Partition decision : Vertical two-partition (top , bottom ).

[0123] ELSE (IF AND OR extremely high) Then the surface has complex twist in both directions, e.g. a corner point, or extremely large, e.g. just hit a single isolated protrusion.

[0124] Partition decision : Four-quadrant partition ( , , , ).

[0125] Step S9.3: Generate sub-region target points

[0126] The central controller calculates a list of sub-region hover points that the drone FCS needs to move to in sequence, according to the of S9.2 .

[0127] Calculate the offset vector in the coordinate system: (left sub-region center offset) (Right sub-region center offset) (Center offset of the upper sub-region) (Sub-region center offset) according to ,and and Movable end alignment, arrive rotation matrix Equivalent to .

[0128]

[0129]

[0130]

[0131] Generate FCS target point list FCS controls Drones need to be in Perform translation in the coordinate system.

[0132]

[0133] IF = Horizontal two-part division: in

[0134] IF = Vertical two-part partitioning: in

[0135] IF = Four-quadrant partitioning: in,

[0136] Step S9.4: Execute sub-region loop processing. The central controller enters the iteration loop and traverses the list. Hover points in each sub-region .

[0137] S9.4.1 Move to Sub-area: The central controller sends a move and hover command to the FCS, with the target point being... FCS controls the drone to move to And hover again stable.

[0138] S9.4.2 Recheck: The UAV is in stable hover. The central controller reactivates S3-S7 full procedure: Acquire new data frame , solve new attitude correction angle , . Drive adjustment to the new normal attitude. Calculate new flatness error .

[0139] Re-decision: IF (sub-area flat): Determine the corresponding sub-area is reliable, set .

[0140] IF (sub-area still complex): Determine the corresponding sub-area is still unreliable, set .

[0141] S9.4.3 Execute sub-area spraying or skip: IF : The sub-area passes the check, and the attitude adjustment is reliable.

[0142] Execute Spot Spray: The central controller "executes S8.1, activates . Since the UAV is in hover state ( ), the cooperative flight of S8.2 is converted to "timed spraying. The central controller maintains turn on a preset Spot Spray duration .

[0143] The calculation is based on the sub-area area , , where is the number of partitions 2 or 4, . Nominal volume flow of the spray gun at standard pressure. After the end, the controller turns off .

[0144] IF : The sub-area cannot meet the local approximate plane assumption even after partitioning. Execute skip: The central controller maintains off. And mark this sub-area The coordinates of the abnormal region are recorded in the abnormal region log for subsequent manual inspection or processing.

[0145] Step S9.5: Resuming global path flight When all in the list are processed, the central controller determines that the complex region has been processed.

[0146] The central controller sends a command to the FCS to return to the position at which the pause in S9.1 occurred. .

[0147] The central controller sends a resume path command to the FCS. The FCS exits the hover state, reactivates the stable flight tracking task, and controls the UAV to continue flying from the current position to the next global path waypoint .

[0148] The system exits S9 and returns to the standard cycle of S2-S8.

[0149] This embodiment is the core adaptive mechanism of the present application. Through the closed-loop process of pause-analysis-partition-move-checkpoint-jet-recovery, the limitations of S4 / S5 based on the assumption of local approximate plane at complex geometric features such as welds, stiffeners, or sharp corners of large ships are solved.

[0150] When the standard algorithm of S4 / S5 fails ( ), the present application does not simply skip the region, but switches to a more detailed and reliable processing strategy.

[0151] Data-driven partitioning makes the partitioning decision (horizontal, vertical, or four-quadrant) not blind, but based on the actual geometric features that caused the check failure, improving the success rate of re-checking. Point jet ensures that the coating thickness can be more accurately controlled even in the hover state. At the same time, the skip logic and abnormal region log function ensure that the system has a safe exit mechanism when facing recursive complexity (i.e., the sub-region is still complex), avoiding infinite loops or forced spraying in an incorrect attitude, thereby implementing the quality-first principle on extremely complex curved surfaces.

[0152] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the above-mentioned automatic spraying method of adaptive adjustment of spraying attitude when executing the computer program.

[0153] A computer readable storage medium, the computer readable storage medium storing a computer program, the computer program being executed by a processor to implement the above-mentioned automatic spraying method of adaptive adjustment of spraying posture.

[0154] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware, and the computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiment methods. Any reference to memory, storage, database or other medium used in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0155] In the specification, the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the difference from other embodiments. In particular, for the embodiments described later, the description is relatively simple, and the relevant parts can be referred to the part of the foregoing embodiments.

[0156] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An automated spraying method for adaptively adjusting spraying attitude, characterized in that the method... include: Control the drone to perform stable flight tracking according to the preset global path waypoints; During stable flight tracking, synchronous data frames of the target's actual surface are continuously collected through a five-point laser sensor array; The attitude correction angle is calculated in real time based on the synchronous data frame; the two-axis gimbal is controlled to perform attitude correction angle to adjust the spraying attitude of the spraying unit. The smoothness error is calculated in real time based on the synchronous data frame; the smoothness error is compared with the preset smoothness threshold to make a spraying decision; When the smoothness error is not greater than the smoothness threshold, the actual surface is determined to be smooth, and a one-time spraying is performed; When the smoothness error exceeds the smoothness threshold, the actual surface is determined to be complex, and adaptive zone spraying is performed.

2. The automated spraying method with adaptive adjustment of spraying attitude according to claim 1, characterized in that, The five-point laser sensor array includes four corner lasers. and a center point laser Synchronization data frames in The time format is: in, The four corner lasers are respectively located at Distance measured at any time For the center point laser in The actual center distance measured at any given time.

3. The automated spraying method for adaptively adjusting spraying attitude according to claim 2, characterized in that, The steps for real-time calculation of attitude correction angles include: calculating the horizontal distance difference. and vertical distance difference : Calculate the attitude correction angles, including the yaw correction angle. and pitch correction angle : in, Given the known horizontal width of the sensor array, The known vertical height of the sensor array.

4. The automated spraying method for adaptively adjusting spraying attitude according to claim 2, characterized in that, The steps for real-time calculation of smoothness error include: calculating the expected center distance. : Calculate the smoothness error : .

5. An automated spraying method for adaptively adjusting spraying posture according to claim 1 or 4, characterized in that, The steps for performing a single spray coating include: activating the spray coating unit; while the spray coating unit remains on, the stable flight tracking step, the solution and control step, and the calculation and comparison step are executed in parallel and continuously to achieve coordinated spray coating flight.

6. An automated spraying method for adaptively adjusting spraying posture according to claim 2 or 4, characterized in that, The steps involved in performing adaptive zone spraying, which divides the area into multiple sub-regions, include: when the smoothness error is greater than a smoothness threshold... Calculate the horizontal distortion at time. and vertical twist : Will and With the distortion threshold Compare and make a partitioning decision based on horizontal two-partitioning, vertical two-partitioning, or four-quadrant partitioning.

7. An automated spraying method for adaptively adjusting spraying attitude according to claim 6, characterized in that, The steps for controlling the drone to move sequentially and align with the sub-regions include: in the sensor array coordinate system Define the sub-region center offset vector corresponding to the partitioning decision; obtain the... Real-time UAV body coordinate system Relative to the sensor array coordinate system rotation matrix The sub-region center offset vector is rotated using a rotation matrix. Transformed into an airframe offset vector; based on the UAV's current position when paused. Based on the body offset vector, calculate the hovering point of the corresponding sub-region. Control the drone to move to the hovering point in the sub-region. .

8. An automated spraying method for adaptively adjusting spraying attitude according to claim 7, characterized in that, The steps for performing spot spraying include: while the drone is hovering, activating the spraying unit for a preset spot spraying duration. ; Based on sub-region area and nominal volumetric flow rate calculate: in, For the target coating thickness, This represents the number of sub-regions in the partition.

9. An automated spraying method for adaptively adjusting spraying attitude according to claim 3, characterized in that, The steps for controlling a two-axis gimbal to perform attitude correction include: setting the pitch axis control error. and yaw axis control error : The control commands, specifically the pitch axis control commands, are calculated using a PID control algorithm. : in, For the gain coefficient of the pitch-axis PID controller, It is the integral variable.

10. An automated spraying system adaptable to adjusting spraying posture, characterized in that, The system includes: Central control module: Controls the UAV to perform stable flight tracking according to the preset global path waypoints; Acquisition module: During stable flight tracking, it continuously acquires synchronous data frames of the target's actual surface through a five-point laser sensor array; Attitude calculation module: calculates attitude correction angle in real time based on synchronous data frames; controls the two-axis gimbal to perform attitude correction angle to adjust the spraying attitude of the spraying unit; Decision module: Calculates smoothness error in real time based on synchronous data frames; compares the smoothness error with a preset smoothness threshold to make a spraying decision; When the smoothness error is not greater than the smoothness threshold, the actual surface is determined to be smooth, and a one-time spraying is performed; When the smoothness error exceeds the smoothness threshold, the actual surface is determined to be complex, and adaptive zone spraying is performed.

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