Space Spraying Positioning Method for Large Surfaces of Steel Structures by Overhead Spraying Robots

Abstract

Elevated spraying robot steel structure large surface space spraying positioning method, belonging to the technical field of intelligent manufacturing and mechatronics. This method selects the corresponding elevated spraying robot according to the operation requirements; sets the ground travel trajectory of the spraying robot in the spraying area, and each spraying robot is equipped with a corresponding ground auxiliary operation vehicle system; conducts elevated spraying robot steel structure large surface space spraying positioning; selects the spraying path plan according to the actual operation space and process requirements of the dock; conducts spraying operations and completes the post-treatment work. This method is applicable to the spraying of steel structure large surface space, and can effectively solve problems such as difficult space positioning of robots during spraying operations in the dock and low efficiency of manual discrimination of different trajectories. At the same time, it realizes effective spatial positioning control of the robot, reasonably plans the distribution of operation workstations, improves the operation quality of the elevated spraying robot, and optimizes the operation process of the equipment.

Description

Technical Field

[0001] The present invention relates to a spatial spraying positioning method for large steel structure surfaces by an overhead spraying robot, belonging to the fields of intelligent manufacturing and mechatronics. Background Art

[0002] The development of new quality productivity in the shipbuilding field is an important part of the digital transformation action of the manufacturing industry. With the continuous deepening of the construction of China's modern industrial system, corresponding progress has been made in the research of various industrial robot-related technologies in the shipbuilding field. Due to the long-term operation of ships in high-temperature and high-salt environments, the outer plates are extremely vulnerable to the corrosion of seawater and the atmosphere, as well as the attachment of marine organisms. At the lightest, it affects the sailing speed of the ship, and at the heaviest, it destroys the structural stability of the ship and reduces the service life of the ship. Therefore, it is necessary to spray protective paint on the outer plates of the ship, and at the same time, high-quality spraying needs to be ensured. At present, the spraying of ship outer plates is carried out manually. Workers hold spray guns and use aerial work platforms to spray the outer plates. During the operation, multiple people often need to cooperate. In addition, this method also has the risk of falling from a height.

[0003] Using an overhead spraying robot to replace manual spraying of large ship outer surfaces reduces the risk of falling from a height during manual high-altitude operations, avoids direct contact between people and toxic volatile gases, improves the operation efficiency and reduces the safety risk. Among them, the low degree of intelligence of spraying equipment, the low operation management efficiency of spraying equipment, and the high spraying rework rate are important factors restricting the ship spraying efficiency. Secondly, considering that ship painting is a technical job integrating technologies such as chemical engineering, machinery, electricity, and fluid dynamics, the professional technical requirements for operators are relatively high. Therefore, multiple overhead spraying robots are used for collaborative operation to further optimize the operation efficiency.

[0004] Controlling the robot to complete the spatial positioning of the steel hull surface and the operation trajectory planning in the dock is the key to using an overhead spraying robot to replace manual work. Due to the limited space in the dock and the large volume of the robot, safety hazards are likely to occur during the operation. In addition, the spraying process of ship outer plates is complex. The distance between the spray gun and the steel hull surface directly affects the quality of the paint film and the operation efficiency. Different from manual operation, when the spraying robot operates, it needs to set a preset trajectory according to the painting requirements to prevent situations such as paint leakage and repeated overspray, which will delay the project progress and affect the economic efficiency of the shipyard. Summary of the Invention

[0005] Aiming at the problems existing in the above-mentioned ship outer plate spraying operation process, the present invention provides a spatial spraying positioning method for large steel structure surfaces by an overhead spraying robot, which controls the robot to complete the spatial positioning of the steel hull surface and the operation trajectory planning in the dock, so as to effectively address the problems such as the difficulty of robot spatial positioning and the low efficiency of manual discrimination of different trajectories during the spraying operation in the dock.

[0006] The technical solution adopted by the present invention is: a method for positioning the spraying of large steel structure surfaces by an overhead spraying robot. The steps of this method are as follows:

[0007] Step S1: Select the number of hulls for which the spraying robot needs to perform spraying operations and the working area of the outer surface of the hull. According to the needs of the operations in the dock, select 3 corresponding overhead spraying robots, namely the first spraying robot, the second spraying robot, and the third spraying robot. Divide the dock into three main spraying areas, with each spraying robot corresponding to a different area. The 3 robots are respectively used to complete the spraying tasks of the large surfaces between the flat side line and the gunwale top line of the left and right sides of the first ship to be sprayed and the second ship to be sprayed. The distance between the two ships to be sprayed is 5 m. The straight bottom part of the hull and the bow and stern frames are supplemented with spraying using other in-dock spraying equipment.

[0008] Step S2: Set the travel trajectory of the spraying robot in different main spraying areas. Each spraying robot is equipped with a corresponding ground auxiliary operation vehicle. Control the spraying robot body to drive into the spraying area, and keep the distance between the robot body and the outer surface of the ship to be sprayed at 3 m. Set the initial spraying position, and the robot runs along the ground walking trajectory, and the distance from the outer surface of the ship remains unchanged all the time. The first spraying robot operates within the working range of the first main spraying area according to its preset ground walking trajectory, the second spraying robot operates within the working range of the second main spraying area according to its preset ground walking trajectory, and the third spraying robot operates within the working range of the third main spraying area according to its preset ground walking trajectory. Each set of ground auxiliary operation vehicles has functions such as paint supply and paint mist recovery, is connected to the operation execution end of the robot through pipelines, and can cooperate with the spraying robot in operations.

[0009] Step S3: Perform positioning for the spraying of large steel structure surfaces by the overhead spraying robot. The specific control steps are as follows:

[0010] Step S3.1: Issue an instruction to start spatial positioning for the overhead spraying robot;

[0011] Step S3.2: Ground positioning of the overhead spraying robot body. To determine the bottom working position of the robot and avoid collisions during work, it is necessary to complete the confirmation of the ground position of the robot body. The laser radar installed on the robot body emits laser beams and receives reflected light to complete the detection of the working environment. The front laser radar continuously scans the working surface ZOY directly facing the robot body and feeds back the reflection of the laser points on the working surface. The rear laser radar continuously scans the working surface XOY facing the side of the robot body and feeds back the reflection of the laser points on the XOY plane; analyze the geometric changes between consecutive laser radar frames to perform real-time odometry and distance calculations. The distance from the robot body base to the XOY plane is represented by R 1 represented as R1 The value range is between 3 and 3.5 m, and the distance from the robot body base to the ZOY plane is represented by R 2 indicating that R 2 the value range of L min , L max , then the ground coordinates of the overhead spraying robot body are represented as P 底 ( R 2 , 0, R 1 ); Based on this position coordinate, the overhead spraying robot system fuses the above multi-frame radar data to optimize the ground pose of the body, iterates the pose trajectory, and sends real-time positioning information to the robot system.

[0012] Step S3.3: Numerical control of the telescopic value at the end of the robot's large arm mechanism. The large arm mechanism includes the bottom large arm and the front small arm. To keep the nozzle at the execution end of the robot within the optimal spraying range with the wall surface and avoid situations such as too thick a film thickness when the spraying distance is too close and too thin a film thickness when the distance is too far, the rotation and telescopic amplitudes and angles of each joint of the robot's large arm mechanism are regulated to achieve numerical control of the end change. The bottom large arm of the robot is driven to telescope. The pull rope sensor of the bottom large arm is installed at the front joint of the robot to detect the telescopic length between the XOY plane. The built-in large arm rotary encoder in the sensor is connected to the pull rope reel. As the robot's large arm telescopes, the reel rotates, and the encoder generates corresponding pulse signals and transmits them to the robot control system. The signal is converted into the telescopic length between the execution end of the overhead spraying robot and the XOY plane as η 1 , η 1 the value range of d 1min , d 1max ; The pull rope sensor of the front small arm is installed at the front joint of the robot's small arm to detect the telescopic length between the ZOX plane. The signal conversion is completed through the built-in small arm rotary encoder and transmitted to the robot control system. The telescopic length between the execution end of the overhead spraying robot and the ZOX plane is represented by η 2 indicating that η 2 the value range of d 2min , d 2maxThere is a space; a terminal draw-wire sensor is installed at the connection between the robot's end effector and the forearm to detect the telescopic length between the ZOY plane. When the end effector is driven by the end motor to expand and contract, the moving part drives the draw-wire, causing the draw-wire to be released or retracted from the reel inside the terminal draw-wire sensor, converting the draw-wire displacement into an electrical signal for transmission. The telescopic length between the end effector of the overhead spraying robot and the ZOY plane is represented by η 3 which is expressed as η 3 and the value range of d 3min is between d 3max .

[0013] Step S3.4: Control the angular amplitude variation of the robot's upper arm mechanism. A bottom swing cylinder is installed on the bottom of the robot's upper arm, and a first angle sensor is installed on the bottom swing cylinder. The installation boss of the first sensor is used for positioning to control the amplitude variation of the upper arm; a front swing cylinder is installed on the front end of the forearm, and a second angle sensor is installed on the front swing cylinder. The installation boss of the second sensor is used for positioning to control the angular amplitude variation of the forearm. When the bottom swing cylinder or the front swing cylinder is controlled to act, it drives the corresponding angle sensor to rotate. The potentiometer inside the angle sensor generates a rotational voltage signal of the robot's upper arm mechanism proportional to the rotation angle and transmits the signal. The robot control system converts the original signal into the specific rotational angle value of the overhead spraying robot's upper arm mechanism. The rotation angle of the upper arm is θ 1 and the rotation angle of the forearm is θ 2 .

[0014] Step S3.5: Establish the overall spatial positioning relationship of the overhead spraying robot. After completing the initialization settings, set the distance R 1 from the robot's body base to the XOY plane, the distance R 2 from the robot's body base to the ZOY plane, import the ground coordinates P 底 ( R 2 , 0, R 1 ) of the robot's body, determine the target position when the robot performs the hull spraying task in the dock, and establish the spatial positioning coordinates P G ( x G , y G , z G ) of the overhead spraying robot, where:

[0015] x G =R 2 +η 1 +M 1 cosθ 1 +M 2 cosθ 2

[0016] y G =η 2 +M 1 sinθ 1 +M 2 sinθ 2

[0017] z G =R 1 +η 3

[0018] R 1 It represents the distance from the robot body base to the XOY plane, R 1 and it is between 3 and 3.5 m; R 2 It represents the distance from the robot body base to the ZOY plane, R 2 and its value range is within L min , L max ;

[0019] η 1 It represents the telescopic length between the execution end of the overhead spraying robot and the XOY plane, η 1 and its value range is within d 1min , d 1max ;

[0020] η 2 It represents the telescopic length between the execution end of the overhead spraying robot and the ZOX plane, η 2The value range of d 2min , d 2max ;

[0021] η 3 represents the telescopic length between the execution end of the overhead spraying robot and the ZOY plane, η 3 The value range of d 3min , d 3max ;

[0022] θ 1 represents the rotation angle of the boom, θ 2 represents the rotation angle of the forearm, M 1 represents the length of the boom, M 2 represents the length of the forearm.

[0023] Step S4: The spraying robot starts working from the initial position, and sets the working path of the robot according to the actual working space of the dock and the requirements of the spraying process. The method includes:

[0024] The method for setting the working path plan of the robot according to the actual working space of the dock and the requirements of the spraying process is:

[0025] According to the occupied area A of the robot working path plan and the working efficiency E, combined with the actual ground working area range limit interval [n, m] of the dock, select the optimal working path; the occupied area of the optimal working path plan is A i satisfies the following conditions: n ≤ A i ≤ m. For each path plan, its plan benefit coefficient function is , check whether the occupied area of each plan is within the limit interval. If only one plan meets the conditions, the plan that meets the conditions is the working path of the robot; if multiple plans meet the conditions, select the plan with the highest score as the working path plan;

[0026] Plan 1 is the "horizontal bow-shaped" large-area continuous spraying trajectory. The spraying robot operates in the "horizontal bow" shape. The execution end sprays horizontally on the large surface from the bow to the stern of the ship. After the execution end descends, it sprays horizontally on the large surface from the stern to the bow of the ship, and repeats until the spraying is completed;

[0027] Plan 2 is the "vertical bow-shaped" large-area continuous spraying trajectory. The spraying robot sprays from top to bottom in the "vertical bow" shape, and after the overhead spraying robot body moves horizontally, it sprays from bottom to top, and repeats from the bow to the stern of the ship until the spraying is completed;

[0028] The third solution is the "vertical one-character" multi-region combined spraying trajectory. The spraying robot sprays from top to bottom in the shape of a "vertical one". After the elevated spraying robot body moves horizontally, the robot's boom mechanism is lifted again and then sprays from top to bottom, repeating until the spraying is completed.

[0029] The fourth solution is the "horizontal arch character" multi-region combined spraying trajectory. The working area is divided into two or more regions. Inside a single region, the spraying robot operates in the shape of a "horizontal arch". The execution end sprays horizontally from one end to the other end of the large region. After the execution end descends, it returns to spray, repeating until the spraying of a single region is completed. The elevated spraying robot body moves horizontally to the next spraying region and repeats the spraying operation within a single region until all single regions are completely sprayed.

[0030] The ground operator activates the control key, and the robot starts operating according to the trajectory. The feeding pump in the ground auxiliary operation vehicle starts, and begins to transport the evenly stirred paint into the feeding pipeline. The execution end of the robot is provided with corresponding recovery holes, and the toxic volatile gases overflowed during spraying are recovered to the ground system through the paint mist recovery pipeline.

[0031] Step S5: Three spraying robots complete the spraying operation on the large surface area of the hull according to the predetermined trajectory, and enter the post-spraying treatment work. The first spraying robot and the third spraying robot drive out of the spraying area. The second spraying robot rotates its body 180°, drives to the left side position of the second ship to be sprayed, and is 50 - 60 cm away from the outer surface of the ship. Spray from the stern area to the bow area, and repeat the process of the above step S3 until the task ends. Beneficial effects: This method uses lidar to scan the working environment in real time to ensure that the robot does not collide and provides accurate body ground position information; precisely regulates the boom extension and angle through the rope-pulling sensor and rotary encoder to maintain the best spraying distance between the nozzle and the wall surface, and uses the angle sensor to precisely adjust the angles of the boom and forearm to ensure flexibility and accuracy during the spraying process. This method is applicable to the spraying of large steel structure surfaces, controls the robot to complete the spatial positioning of the steel surface of the hull and the operation trajectory planning in the dock, and can effectively address problems such as difficult spatial positioning of the robot during dock spraying operations and low efficiency of manual discrimination of different trajectories.

[0032] The present invention integrates lidar and various sensors to control the distance between the spray gun and the steel surface of the hull to ensure the paint film quality and operation efficiency; improves the positioning accuracy, operation safety, and spraying quality of the elevated spraying robot, realizes the integrated management from start-up positioning to spatial positioning, improves the stability and reliability of the system, greatly improves the operation efficiency and quality, reduces the operation cost, and promotes the development of new quality productivity in the shipbuilding industry. Description of the Drawings

[0033] Figure 1 The operation area division diagram inside the dock for the elevated spraying robot provided by the embodiment of the present invention.

[0034] Figure 2 The combined diagram of the elevated spraying robot system provided by the embodiment of the present invention.

[0035] Figure 3 The ground walking track line diagram inside the dock for the elevated spraying robot provided by the embodiment of the present invention.

[0036] Figure 4 The space spraying positioning structure diagram for the large surface of the steel structure of the elevated spraying robot provided by the embodiment of the present invention.

[0037] Figure 5 The side view of the operation scene inside the dock for the elevated spraying robot provided by the embodiment of the present invention.

[0038] Figure 6 The operation flow chart inside the dock for the elevated spraying robot provided by the embodiment of the present invention.

[0039] Figure 7 The continuous spraying track diagram of "vertical bow shape" for Case 1 provided by the embodiment of the present invention.

[0040] Figure 8 The continuous spraying track diagram of "horizontal bow shape" for Case 2 provided by the embodiment of the present invention.

[0041] Figure 9 The combined spraying track diagram of "vertical one shape" for multiple areas in Case 3 provided by the embodiment of the present invention.

[0042] Figure 10 The combined spraying track diagram of "vertical bow shape" for multiple areas in Case 4 provided by the embodiment of the present invention.

[0043] In the figure: 1a, the first spraying robot; 1b, the second spraying robot; 1c, the third spraying robot; 1d, the elevated spraying robot body; 1e, the robot's large arm mechanism; 1f, the robot's operation execution end; 1g, the feeding and recycling pipeline; 1h, the ground auxiliary operation vehicle; 2a, the first ship to be sprayed; 2b, the second ship to be sprayed; 2c, the first main spraying area; 2d, the second main spraying area; 2e, the third main spraying area; 3, the ground walking trajectory of the spraying robot; 3a, the ground walking trajectory of the first spraying robot; 3b, the ground walking trajectory of the second spraying robot; 3c, the ground walking trajectory of the third spraying robot; 3d, the hull boundary line; 4a, the initial spraying point of Plan 1; 4b, the initial spraying small area of Plan 1; 4c, the second spraying small area of Plan 1; 4d, the first spraying trajectory of Plan 1; 4e, the first spraying stop point of Plan 1; 4f, the first robot downward movement trajectory of Plan 1; 4g, the second spraying start point of Plan 1; 4h, the second spraying trajectory of Plan 1; 4i, the second spraying stop point of Plan 1; 4j, the second robot downward movement trajectory of Plan 1; 4k, the third spraying start point of Plan 1; 4m, the third spraying trajectory of Plan 1; 4n, the third robot downward movement trajectory of Plan 1; 4o, the fourth spraying start point of Plan 1; 4p, the fourth spraying trajectory of Plan 1; 5, the flat edge line; 5a, the initial spraying point of Plan 2; 5b, the initial spraying small area of Plan 2; 5c, the second spraying small area of Plan 2; 5d, the first spraying trajectory of Plan 2; 5e, the first spraying stop point of Plan 2; 5f, the first robot lateral movement trajectory of Plan 2; 5g, the second spraying start point of Plan 2; 5h, the second spraying trajectory of Plan 2; 5i, the second spraying stop point of Plan 2; 5j, the second robot lateral movement trajectory of Plan 2; 5k, the third spraying start point of Plan 2; 5l, the third spraying trajectory of Plan 2; 5m, the third spraying stop point of Plan 2; 5n, the third robot lateral movement trajectory of Plan 2; 5o, the fourth spraying start point of Plan 2; 5p, the fourth spraying trajectory of Plan 2; 6a, the initial spraying point of Plan 3; 6b, the initial spraying small area of Plan 3; 6c, the second spraying small area of Plan 3; 6d, the first vertical column spraying trajectory of Plan 3; 6e, the first spraying stop point of Plan 3; 6f, the second spraying start point of Plan 3; 6g, the second vertical column spraying trajectory of Plan 3; 6h, the second spraying stop point of Plan 3; 6i, the third spraying start point of Plan 3; 6j, the third vertical column spraying trajectory of Plan 3; 6k, the third spraying stop point of Plan 3; 6l, the ground movement direction of the robot in Plan 3; 6m, the fourth spraying start point of Plan 3; 6n, the fourth vertical column spraying trajectory of Plan 3; 6o, the fourth spraying stop point of Plan 3; 7a, the initial spraying small area in the area near the bow of Plan 4; 7b, the initial spraying point in the area near the bow of Plan 4; 7c, the second spraying small area in the area near the bow of Plan 4; 7d, the first spraying trajectory in the area near the bow of Plan 4; 7e, the first spraying stop point in the area near the bow of Plan 4; 7f, the first descending trajectory of the spraying robot in Plan 4;7g. The second spraying starting point in the area near the bow of Solution 4; 7h. The second spraying trajectory in the area near the bow of Solution 4; 7i. The second spraying stop point in the area near the bow of Solution 4; 7j. The second descending trajectory of the spraying robot in Solution 4; 7k. The third spraying starting point in the area near the bow of Solution 4; 7l. The third spraying trajectory in the area near the bow of Solution 4; 7m. The third spraying stop point in the area near the bow of Solution 4; 7n. The third descending trajectory of the spraying robot in Solution 4; 7o. The fourth spraying starting point in the area near the bow of Solution 4; 7p. The fourth spraying trajectory in the area near the bow of Solution 4; 8a. The initial small spraying area in the area near the stern of Solution 4; 8b. The initial spraying point in the area near the stern of Solution 4; 8c. The second small spraying area in the area near the stern of Solution 4; 8d. The first spraying trajectory in the area near the stern of Solution 4; 8e. The first spraying stop point in the area near the stern of Solution 4; 8f. The fourth descending trajectory of the spraying robot in Solution 4; 8g. The second spraying starting point in the area near the stern of Solution 4; 8h. The second spraying trajectory in the area near the stern of Solution 4; 8i. The second spraying stop point in the area near the stern of Solution 4; 8j. The fifth descending trajectory of the spraying robot in Solution 4; 8k. The third spraying starting point in the area near the stern of Solution 4; 8l. The third spraying trajectory in the area near the stern of Solution 4; 8m. The third spraying stop point in the area near the stern of Solution 4; 8n. The sixth descending trajectory of the spraying robot in Solution 4; 8o. The fourth spraying starting point in the area near the stern of Solution 4; 8p. The fourth spraying trajectory in the area near the stern of Solution 4.; Detailed implementation manners

[0044] Figure 2 The overhead spraying robot system combination provided by the embodiments of the present invention. This robot system includes: an overhead spraying robot body, a feeding and recycling pipeline 1g, and a ground auxiliary operation vehicle 1h. The robot body is connected to the ground auxiliary operation vehicle through the feeding and recycling pipeline. The spraying robot body includes: an overhead spraying robot body 1d, a robot arm mechanism 1e, and a robot operation execution end 1f; the arm mechanism includes a bottom arm and a front small arm; the overhead spraying robot body can achieve left - right lateral movement and self - rotation, and at the same time, as a robot ground moving platform, it is displaced by carrying the operation execution end. The robot arm mechanism connects the overhead spraying robot body and the robot operation execution end. The robot operation execution end includes a spray gun, a paint mist recovery cover, a recovery hole, etc. The ground auxiliary operation vehicle carries spraying feeding equipment and paint mist recovery equipment. Before operation, paint is manually opened and poured into the feeding equipment by workers, and then is transmitted to the robot operation execution end through the pipeline. During operation, the paint mist is recovered by the paint mist recovery equipment through the recovery pipeline.

[0045] Figure 6 The operation process of the overhead spraying robot in the dock provided by the embodiments of the present invention. This process includes:

[0046] Step 1: Select 3 overhead spraying robots according to the number of pre-sprayed ships and the area of the operation area, allocate the corresponding main spraying area for each robot, and complete the preparatory work before spraying operations.

[0047] Select the number of hulls for which the spraying robots need to perform spraying operations and the working area of the large surfaces of the hull steel structures. Select 3 corresponding overhead spraying robots according to the needs of the operations in the dry dock, namely the first spraying robot 1a, the second spraying robot 1b, and the third spraying robot 1c; divide the dry dock into three main spraying areas, with each spraying robot corresponding to a different area. The 3 robots are respectively used to complete the spraying tasks of the large surfaces between the flat side line and the top line of the bulwark on the left and right sides of the first ship to be sprayed 2a and the second ship to be sprayed 2b (as Figure 1 shown).

[0048] Step 2: The first, second, and third spraying robots are respectively operated by ground control personnel and driven into the corresponding first, second, and third spraying areas. The initial spraying positions are all in the bow area of the hull to be sprayed. Set the travel trajectory of each spraying robot, and the distance from the surface of the hull to be sprayed is 3m. Each spraying robot is equipped with a corresponding ground auxiliary operation vehicle system.

[0049] Set the travel trajectories of the spraying robots in different main spraying areas. Each spraying robot is equipped with a corresponding ground auxiliary operation vehicle 1h; control the spraying robot body to drive into the spraying area, and keep the distance between the robot body and the outer surface of the hull to be sprayed at the spraying distance; set the initial spraying position, and the robot runs along the ground travel trajectory 3c of the third spraying robot, and the distance from the outer surface of the hull remains unchanged all the time; the first spraying robot 1a operates within the working range of the first main spraying area 2c according to its preset first spraying robot ground travel trajectory 3a, the second spraying robot 1b operates within the working range of the second main spraying area 2d according to its preset second spraying robot ground travel trajectory 3b, and the third spraying robot 1c operates within the working range of the third main spraying area 2e according to its preset third spraying robot ground travel trajectory 3c; each set of ground auxiliary operation vehicles 1h has a paint supply and paint mist recovery mechanism, which is connected to the operation execution end 1f of the robot through pipelines and can cooperate with the spraying robot during operations.

[0050] Step 3: Perform spatial spraying positioning for the large surfaces of the steel structures of the overhead spraying robots (as Figure 3 and Figure 4 ), and the specific control steps are as follows:

[0051] Step 3.1: Issue a spatial positioning command to start the overhead spraying robot.

[0052] Step 3.2: Ground positioning of the overhead spraying robot body. To determine the working position at the bottom of the robot and avoid collisions during operation, it is necessary to confirm the ground position of the robot body. The lidar installed on the robot body emits laser beams and receives reflected light to complete the detection of the working environment. The front lidar continuously scans the working surface ZOY directly facing the robot body and feeds back the reflection of the laser points on the working surface. The rear lidar continuously scans the working surface XOY facing the side of the robot body and feeds back the reflection of the laser points on the XOY plane; analyze the geometric changes between consecutive lidar frames to perform real-time odometry and distance calculations. The distance from the robot body base to the XOY plane is represented by R 1 which is R 1 with a value range between 3 and 3.5 m. The distance from the robot body base to the ZOY plane is represented by R 2 which is R 2 with a value range in L min , L max . Then the ground coordinates of the overhead spraying robot body are represented as P 底 ( R 2 , 0, R 1 ); Based on this position coordinate, the overhead spraying robot system fuses the above multi-frame radar data to optimize the ground pose of the body, iterates the pose trajectory, and sends real-time positioning information to the robot system.

[0053] Step S3.3: Numerical control of the telescopic value at the end of the robot's big arm mechanism. The big arm mechanism includes the bottom big arm and the front small arm. To keep the nozzle at the execution end of the robot within the optimal spraying range from the wall surface and avoid situations such as too thick a film thickness when the spraying distance is too close or too thin a film thickness when the distance is too far, the rotation and telescopic amplitudes and angles of each joint of the robot's big arm mechanism are adjusted to achieve numerical control of the end changes. The bottom big arm of the robot is driven to extend and retract. The rope-pulling sensor of the bottom big arm is installed at the front joint of the robot to detect the telescopic length between the XOY plane. The built-in big arm rotary encoder in the sensor is connected to the rope-pulling reel. As the robot's big arm extends and retracts, the reel rotates, and the encoder generates corresponding pulse signals and transmits them to the robot control system. The signal is converted into the telescopic length between the execution end of the overhead spraying robot and the XOY plane as η 1 , η 1 with a value range in d 1min , d 1maxThe front-end small-arm drawstring sensor is installed at the joint of the front end of the robot's small arm to detect the telescopic length between the distance from the ZOX plane. It completes signal conversion through the built-in small-arm rotary encoder and transmits the signal to the robot control system, and uses η 2 to represent η 2 The value range of d 2min , d 2max ; At the connection between the robot's execution end and the small arm, a terminal drawstring sensor is installed to detect the telescopic length between the distance from the ZOY plane. When the terminal motor drives the execution end to expand and contract, the moving part drives the drawstring, causing the drawstring to be released or retracted from the reel inside the terminal drawstring sensor, converting the drawstring displacement into an electrical signal to complete the transmission, and using η 3 to represent η 3 The value range of d 3min , d 3max .

[0054] Step 3.4: Control the variable amplitude of the robot's large-arm mechanism joints. A bottom swing cylinder is installed on the bottom large arm of the robot, and a first angle sensor is installed on the bottom swing cylinder. The installation boss of the first sensor is used for positioning to control the large-arm variable amplitude; a front-end swing cylinder is installed on the front-end small arm, and a second angle sensor is installed on the front-end swing cylinder. The installation boss of the second sensor is used for positioning to control the small-arm angle variable amplitude; when the bottom swing cylinder or the front-end swing cylinder is controlled to act, it drives the corresponding angle sensor to rotate. The potentiometer inside the angle sensor generates a robot large-arm mechanism rotation voltage signal proportional to the rotation angle and transmits the signal. The robot control system converts the original signal into the specific rotation angle value of the high-altitude spraying robot's large-arm mechanism. The rotation angle of the large arm is θ 1 , and the rotation angle of the small arm is θ 2 .

[0055] Step 3.5: Establish the overall spatial positioning relationship of the high-altitude spraying robot. Complete the initialization setting, and set the distance R 1 from the robot body base of the high-altitude spraying robot to the XOY plane, and the distance R 2 from the robot body base to the ZOY plane, and import the ground coordinates P 底 (R 2 ,0, R 1 ), determine the target position when the robot performs the hull spraying task in the dock, and establish the spatial positioning coordinates of the overhead spraying robot P G ( x G , y G , z G ), where:

[0056] x G =R 2 +η 1 +M 1 cosθ 1 +M 2 cosθ 2

[0057] y G =η 2 +M 1 sinθ 1 +M 2 sinθ 2

[0058] z G =R 1 +η 3

[0059] R 1 It is expressed as the distance from the robot body base to the XOY plane, R 1 and it is between 3 and 3.5 m; R 2 It is expressed as the distance from the robot body base to the ZOY plane, R 2 The value range of L min , L max is between;

[0060] η 1It represents the telescopic length between the end effector of the overhead spraying robot and the XOY plane. η 1 The value range of d 1min , d 1max is between;

[0061] η 2 It represents the telescopic length between the end effector of the overhead spraying robot and the ZOX plane. η 2 The value range of d 2min , d 2max is between;

[0062] η 3 It represents the telescopic length between the end effector of the overhead spraying robot and the ZOY plane. η 3 The value range of d 3min , d 3max is between;

[0063] θ 1 It represents the rotation angle of the boom. θ 2 It represents the rotation angle of the forearm. M 1 It represents the length of the boom. M 2 It represents the length of the forearm.

[0064] Step 4: The spraying robot starts working from the initial position, and sets the robot's working path according to the actual working space of the dock and the requirements of the spraying process. The method for setting the robot's working path is as follows: Let the occupied area of the first working path plan of the robot be A1, the working efficiency be E1, the occupied area of the second path plan be A2, the working efficiency be E2, the occupied area of the third path plan be A3, the working efficiency be E3, the occupied area of the fourth path plan be A4, and the working efficiency be E4. The actual ground working range limit interval of the dock is [n, m]. The occupied area of the optimal working path plan is A i Satisfies the following conditions: n ≤ A i ≤ m. For each path plan, its plan benefit coefficient function is , check whether its occupied area is within the limit interval. If the condition is satisfied, select the path plan with the highest score: .

[0065] The ground operator activates the control key, and the robot starts working according to the trajectory. The feeding pump of the ground auxiliary working vehicle starts within 1 h and begins to transport the evenly stirred paint into the feeding pipeline. The working end 1f of the robot is provided with corresponding recovery holes, and the toxic volatile gases spilled during spraying are recovered to the ground system through the paint mist recovery pipeline.

[0066] Step 5: The boom mechanism of the first spraying robot 1a is driven to rise to the top working point A1 in the left working area of the first ship to be sprayed, and the distance between the working end and the hull surface is adjusted to L1. The range of the size of L1 is 50 - 60 cm. The boom mechanism of the second spraying robot 1b is driven to rise to the top working point B1 in the right working area of the first ship to be sprayed, and the distance between the working end and the hull surface is adjusted to L1. The range of the size of L1 is 50 - 60 cm. The boom mechanism of the third spraying robot 1c is driven to rise to the top working point D1 in the right working area of the second ship to be sprayed, and the distance between the working end and the hull surface is adjusted to L1. The range of the size of L1 is 50 - 60 cm.

[0067] Step 6: The body parts of each spraying robot always move along the preset ground walking trajectory 3c of the third spraying robot, and the distance from the hull boundary line is kept as L2. The range of the size of L2 is 3 m. The robot moves until the operation of the current working station is completed, and then enters the next working station, repeating this process in a cycle.

[0068] Step 7: Each spraying robot drives the working end to move vertically downward by the boom mechanism, and the motor drives to complete the spraying from the flat side line direction of the hull to the last section area. The boom mechanism of the first spraying robot contracts, and the paint supply control valve is closed. The robot drives away from the first and third main spraying areas respectively according to the set trajectories. It is judged whether the left side of the second ship to be sprayed needs to be sprayed. If not, the second spraying robot drives away from the second main spraying area, and the in-dock operation of the spraying robot ends, and the post-spraying treatment work is carried out manually. If so, the body of the second spraying robot rotates 180° and sprays according to the set traveling trajectory. The boom mechanism is driven to rise to the top working point C1 in the left working area of the second ship to be sprayed, and the distance between the working end and the hull surface is adjusted to L1. The range of the size of L1 is 50 - 60 cm. Repeat the above operation process until the end, and then carry out the post-spraying treatment work. Embodiment

[0069] Figure 7Scheme 1 shows a continuous spraying trajectory in a large area in the shape of a "horizontal arch character". The spraying robot operates in the shape of a "horizontal arch", and the execution end sprays horizontally in a large area from the bow to the stern, descending and reciprocating. During specific operations, spraying is carried out along the first spraying trajectory 4d of Scheme 1 from the initial spraying point 4a of the large surface of Scheme 1, and the area of the small spraying area is 0.5m×1m. First, start the control valve to complete the spraying of the initial small spraying area 4b of Scheme 1. The robot body moves 1m to the second small spraying area 4c of Scheme 1 for spraying, and repeats this process until the robot reaches the first spraying stop point 4e of Scheme 1, the spraying pipeline control valve is closed, and the spraying of the first horizontal row area stops. The robot's large arm mechanism 1e drives vertically downward by 0.5m along the first robot downward movement trajectory 4f of Scheme 1 to the second spraying starting point 4g of Scheme 1, and the spraying of the second horizontal row area starts. The spraying pipeline control valve is started, and the previous steps are repeated along the second spraying trajectory 4h of Scheme 1 until the spraying operation of the entire large surface of the hull on this side is completed.

[0070] Figure 8 Scheme 2 shows a continuous spraying trajectory in a large area in the shape of a "vertical arch character". The spraying robot sprays from top to bottom in the shape of a "vertical arch", and after the body moves horizontally, it sprays from bottom to top, reciprocating. During specific operations, spraying is carried out along the first spraying trajectory 5d of Scheme 2 from the initial spraying point 5a of Scheme 2, and the area of the small spraying area is 0.5m×1m. First, start the control valve to complete the spraying of the initial small spraying area 5b of Scheme 2. The robot's large arm mechanism 1e drives the operation execution end to move vertically downward, moving down 0.5m to complete the spraying of the second small spraying area 5c of Scheme 2. Repeat the above process until reaching the first spraying stop point 5e of Scheme 2, the spraying pipeline control valve is closed, and the spraying of the first vertical column area is completed. The robot body drives along the first horizontal movement trajectory 5f of the robot in Scheme 2 to the second spraying starting point 5g of Scheme 2 and stops. Start the control valve to start spraying again. The robot's large arm mechanism 1e moves upward along the second spraying trajectory 5h of Scheme 2 to the second spraying stop point 5i of Scheme 2 to complete the spraying of the second vertical column area, and repeat the previous steps until the spraying operation of the entire large surface of the hull on this side is completed.

[0071] Figure 9Solution 3 shows a "vertical one - character" multi - area combined spraying trajectory. The spraying robot sprays from top to bottom in the shape of a "vertical one - character". After the vehicle body moves horizontally, the boom is lifted again and then sprays from top to bottom, repeating this process. During specific operations, the spraying robot sprays along the first vertical column spraying trajectory 6d of Solution 3 starting from the initial spraying point 6a of Solution 3. The size of the small spraying area is 0.5m × 1m. First, start the control valve to complete the spraying of the initial small spraying area 6b of Solution 3. The boom mechanism 1e of the robot drives the operation execution end to move vertically downward. After moving down 0.5m, complete the spraying of the second small spraying area 6c of Solution 3. Repeat the above process until reaching the first spraying stop point 6e of Solution 3. The spraying pipeline control valve is closed, and the spraying of the first vertical column area is completed. The vehicle body of the robot moves 0.5m along the robot ground movement direction 6l of Solution 3 to the second vertical column spraying area. The boom mechanism 1e of the robot drives the operation execution end to move vertically upward to reach the second spraying starting point 6f of Solution 3. The control valve is started to start spraying, and the boom moves downward along the second vertical column spraying trajectory 6g of Solution 3 until reaching the second spraying stop point 6h of Solution 3 to end the operation. Repeat the above steps until the spraying operation of the entire large surface of the hull on this side is completed.

[0072] Figure 10Scheme Four shows a "transverse arch-shaped" multi-region combined spraying trajectory. The working area is divided into two or more regions. In a single region, the spraying robot operates in a "transverse arch" shape. The execution end sprays horizontally from one end to the other end of the large region. After the execution end descends, it returns to spray, repeating until the spraying of a single region is completed. Then the body of the overhead spraying robot 1d moves horizontally to the next spraying region and repeats the spraying operation within a single region until the spraying of all single regions is completed. During specific operation, the robot starts from the initial spraying point 7b in the region near the bow of Scheme Four and operates along the first spraying trajectory 7d in the region near the bow of Scheme Four. The area of the small spraying region is 0.5m×1m. First, start the control valve to complete the spraying of the initial small spraying region 7a in the region near the bow of Scheme Four. The robot body moves 1m to the second small spraying region 7c in the region near the bow of Scheme Four for spraying, and repeats this process. Until the robot reaches the first spraying stop point 7e in the region near the bow of Scheme Four, the spraying pipeline control valve is closed, and the spraying of the first horizontal row region stops. The large arm mechanism 1e of the robot drives vertically downward by 0.5m along the first descending trajectory 7f of the spraying robot in Scheme Four to the second spraying starting point 7g in the region near the bow of Scheme Four, and the spraying of the second horizontal row region starts. The spraying pipeline control valve is started, and the previous steps are repeated along the second spraying trajectory 7h in the region near the bow of Scheme Four until the spraying of the first large region is completed. The robot body drives to move to the initial spraying point of the next region, repeats the above spraying process to complete the spraying of the large region at the bow, and the robot moves to the region at the stern.The robot body is positioned to the initial spraying point 8b of the fourth scheme near the stern area through the guide rail, and the robot arm mechanism is aligned with the initial spraying small area 8a of the fourth scheme near the stern area, and the size of the small area is maintained at 0.5m×1m operation unit; the spray pipeline control valve is started, and it moves horizontally along the first spraying trajectory 8d of the fourth scheme near the stern area; after completing 1m of travel, it reaches the second small spraying area 8c of the fourth scheme near the stern area for continuous spraying; repeat the horizontal reciprocating motion until it reaches the first spraying stop point 8e of the fourth scheme near the stern area; the control valve is closed to complete the first row of spraying operation; the arm mechanism vertically descends 0.5m along the fourth descending trajectory 8f of the spray robot in scheme four; the robot arm mechanism shrinks to the second spraying small area 8c of the fourth scheme near the stern area Starting point 8g; open the control valve to perform the second horizontal row spraying along the second spraying trajectory 8h of Scheme 4 near the stern area; repeat the above process until reaching the second spraying stop point 8i of Scheme 4 near the stern area to perform the third vertical displacement: descend 0.5m along the fifth descending trajectory 8j of Scheme 4 spraying robot to the third spraying starting point 8k of Scheme 4 near the stern area; complete the third spraying stop point 8m of Scheme 4 near the stern area along the third spraying trajectory 8l of Scheme 4 near the stern area; perform the fourth vertical displacement: descend 0.5m along the sixth descending trajectory 8n of Scheme 4 spraying robot to the fourth spraying starting point 8o of Scheme 4 near the stern area; complete the horizontal row spraying along the fourth spraying trajectory 8p of Scheme 4 near the stern area, and the spraying operation of all the large surfaces of this side of the hull is completed.

[0073] Finally, it should be noted that the above is merely the technical solution of the present invention and does not limit it; even though the above real-time method is described in detail, it does not limit it; technicians in this field can modify the case described or replace the technology with the same features; but no matter the modification or replacement, it should not deviate from the technical essence of the present invention.

Claims

1. A method for positioning large surface space spraying of an elevated spraying robot steel structure, characterized in that: The method steps include: Step S1: selecting the number of hulls on which the spraying robot needs to perform spraying operations and the large surface area of ​​the hull steel structure; Step S2: setting the travel trajectory of the spraying robot in different main spraying areas, and each spraying robot is equipped with a corresponding ground auxiliary operation vehicle (1h); controlling the spraying robot body to enter the spraying area, and keeping the distance between the robot body and the outer surface of the hull to be sprayed at the spraying distance; setting the initial spraying position, and running along the ground walking trajectory of the spraying robot (3), and keeping the distance from the outer surface of the hull unchanged; Step S3: Perform spray positioning of the large surface space of the steel structure of the overhead spray robot. The specific control steps are as follows: Step S3.1: issuing a spatial positioning instruction for the overhead spraying robot to start; Step S3.2: The body of the overhead spray painting robot is positioned on the ground; the laser radar installed on the robot body emits a laser beam and receives reflected light to complete the working environment detection. The front laser radar continuously scans the working surface ZOY facing the robot body and feeds back the reflection of the laser point on the working surface. The rear laser radar continuously scans the working surface XOY facing the side of the robot body and feeds back the reflection of the laser point on the XOY surface. The geometric changes between consecutive LiDAR frames are analyzed to perform real-time mileage and distance calculations. The distance from the robot body base to the XOY plane is represented by R1, and the value range of R1 is between 3 and 3.5 m. The distance from the robot body base to the ZOY plane is represented by R2, and the value range of R2 is between [L min ,L max ], the ground coordinates of the overhead spraying robot body are expressed as P 底 (R2,0,R1); Step S3.3: Numerical control of the robot's arm mechanism end extension: The arm mechanism includes a bottom arm and a front arm, which drives the robot's bottom arm to extend and retract. The bottom arm pull rope sensor is installed at the front joint of the robot to detect the extension length η1 between the XOY plane and the value range of η1 is [d 1min ,d 1max ]; the front arm pull rope sensor is installed at the front joint of the robot arm to detect the telescopic length η2 between the ZOX plane and the value range of η2 is [d 2min ,d 2max ]; The end pull rope sensor is installed at the connection between the robot execution end and the forearm to detect the telescopic length η3 between the ZOY plane, and the value range of η3 is [d 3min ,d 3max ]between; Step S3.4: Control of the angle variation of the robot's upper arm mechanism joints: The lower arm of the robot is equipped with a lower swing cylinder, on which a first angle sensor is installed, which is positioned using the mounting boss of the first sensor to control the arm's amplitude variation; the front arm is equipped with a front swing cylinder, on which a second angle sensor is installed, which is positioned using the mounting boss of the second sensor to control the arm's angle variation; the upper arm's rotation angle is θ1, and the arm's rotation angle is θ2; Step S3.5: Establish the overall spatial positioning relationship of the overhead painting robot: Complete the initialization setting, set the distance R1 from the overhead painting robot body base to the XOY plane, the distance R2 from the robot body base to the ZOY plane, and import the ground coordinates P of the overhead painting robot body 底 (R2,0,R1), determine the target position of the robot when performing the hull spraying task in the dock, and establish the spatial positioning coordinates P of the overhead spraying robot G (x G ,y G ,z G ),in: x G =R2+η1+M1cosθ1+M2cosθ2 y G =η2+M1sinθ1+M2sinθ2 with G =R1+η3 R1 is the distance from the robot body base to the XOY plane, and R1 is between 3 and 3.5 meters; R2 is the distance from the robot body base to the ZOY plane, and the value range of R2 is [L min ,L max ]between; η1 represents the telescopic length between the execution end of the overhead spraying robot and the XOY plane. The value range of η1 is [d 1min ,d 1max ]between; η2 represents the telescopic length between the execution end of the overhead spraying robot and the ZOX plane. The value range of η2 is [d 2min ,d 2max ]between; η3 represents the telescopic length between the execution end of the overhead spraying robot and the ZOY plane. The value range of η3 is [d 3min ,d 3max ]between; θ1 represents the rotation angle of the upper arm, θ2 represents the rotation angle of the lower arm, M1 represents the length of the upper arm, and M2 represents the length of the lower arm; Step S4: The spraying robot starts to operate from the initial point, and sets the robot operation path plan according to the actual operation space of the dock and the spraying process requirements; Step S5: The spraying robot completes the spraying operation on a large surface area of ​​the hull from the stern area to the bow area according to a predetermined trajectory.

2. The method for spraying positioning of a large surface space of a steel structure by an overhead spraying robot according to claim 1 is characterized in that: In the step S1, three corresponding overhead spraying robots are selected according to the operation requirements in the dock, namely a first spraying robot (1a), a second spraying robot (1b), and a third spraying robot (1c); the dock is divided into three main spraying areas, each spraying robot corresponds to a different area, and the three robots are respectively used to complete the large surface spraying task between the flat side line of the hull and the top line of the bulwark on the left and right sides of the first ship to be sprayed (2a) and the second ship to be sprayed (2b).

3. The method for spraying positioning of a large surface space of a steel structure by an overhead spraying robot according to claim 2 is characterized in that: In the step S2, the first spraying robot (1a) operates within the operating range of the first main spraying area (2c) according to the preset first spraying robot ground walking track (3a), the second spraying robot (1b) operates within the operating range of the second main spraying area (2d) according to the preset second spraying robot ground walking track (3b), and the third spraying robot (1c) operates within the operating range of the third main spraying area (2e) according to the preset third spraying robot ground walking track (3c); each ground auxiliary operation vehicle (1h) is equipped with a paint supply and paint mist recovery mechanism, is connected to the robot operation execution end (1f) through a pipeline, and can cooperate with the spraying robot in operation.

4. The method for spraying positioning of a large surface space of a steel structure by an overhead spraying robot according to claim 1 is characterized in that: In step S4, the method for setting the robot operation path plan according to the actual operation space of the dock and the spraying process requirements is: According to the occupied area A and the operating efficiency E of the robot operation path plan, the optimal operation path is selected in combination with the actual ground operation area range limit interval [n,m] of the dock; the optimal operation path plan occupies an area A i The following conditions are met: n≤A i ≤m, for each path plan, its plan benefit coefficient function is: Check whether the area occupied by each solution is within the restricted range. If only one solution meets the conditions, the solution that meets the conditions is the robot's operation path; if multiple solutions meet the conditions, the solution with the highest score is selected as the operation path solution; Solution 1 is a large-area continuous spraying trajectory in the shape of a "horizontal bow". The spraying robot operates in the shape of a "horizontal bow". The execution end sprays horizontally on a large surface from the bow to the stern. After the execution end descends, it sprays horizontally on a large surface from the stern to the bow, and repeats this process until the spraying is completed. The second scheme is a large-area continuous spraying trajectory in the shape of a "vertical bow". The spraying robot sprays from top to bottom in the shape of a "vertical bow". The elevated spraying robot body (1d) moves horizontally and then sprays from bottom to top, reciprocating from the bow to the stern until the spraying is completed. Solution 3 is a "vertical one" multi-area combined spraying trajectory, in which the spraying robot sprays from top to bottom in a "vertical one" shape, and after the elevated spraying robot body (1d) moves horizontally, the robot arm mechanism (1e) is lifted again, and then sprays from top to bottom, and the process is repeated until the spraying is completed; Solution 4 is a "horizontal bow" multi-area combined spraying trajectory, which divides the working area into more than two areas. In a single area, the spray robot operates in a "horizontal bow" shape. The execution end sprays horizontally from one end of the large area to the other end, and then returns to spray after descending. This process is repeated until the spraying of a single area is completed. The elevated spray robot body (1d) moves horizontally to the next spraying area and re-executes the spraying operation in the single area until all single areas are sprayed.

5. The method for spraying positioning of a large surface space of a steel structure by an overhead spraying robot according to claim 1 is characterized in that: In step S4, after setting the robot's operating path, the ground operator activates the control key, the robot starts to operate according to the trajectory, the feed pump in the ground auxiliary operation vehicle (1h) starts, and begins to transport the evenly stirred paint to the feed pipeline; the robot operation execution end (1f) is provided with a corresponding recovery hole, and the toxic volatile gas overflowed by the spraying is recovered to the ground system through the paint mist recovery pipeline.

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