In-situ automatic repairing device for local coating of airplane

Abstract

The utility model relates to the field of aircraft coating repairing technology research, in particular to an in-situ automatic repairing device for an aircraft local coating. Comprising a mobile operation platform, a 3D camera which is arranged on the mobile operation platform and is used for collecting 2D images and 3D point cloud data of the surface of an airplane, a repairing module which is arranged on the mobile operation platform and is used for coating cleaning or paint spraying, and an upper computer which is used for controlling the mobile operation platform, the 3D camera and the repairing module. Compared with the device in the prior art, the device can automatically inspect, identify and position the damaged area of the coating on the surface of the airplane, and in-situ automatic identification and repair of the damaged special-shaped bent coating on different parts of the surface of the airplane are realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of aircraft coating repair, in particular to an in-situ automatic repair device for aircraft local coating. Background Art

[0002] During transportation, storage and training, aircraft may suffer from collisions, scratches, natural aging and other factors, causing the surface coating to fall off or the physical and chemical properties to change, resulting in the reduction or loss of coating performance, seriously affecting the aircraft's combat effectiveness and battlefield survival safety. In particular, even small damage or defects in the surface coating of key parts will cause a sharp deterioration in performance. Therefore, damage to the aircraft coating must be repaired in a timely manner according to maintenance standards.

[0003] At present, the main way to repair aircraft coatings is to return them to the factory for repair. Although the repair quality is good, the cycle is long and it is difficult to meet the current aircraft maintenance requirements. The in-situ repair of aircraft coating damage is mainly done by directly applying stealth coating or pasting repair stickers. It is fast and efficient, but the repaired coating has a short life and is easy to fall off. At the same time, the sprayed paint generally contains a large amount of highly harmful chemical components such as benzene, toluene, and xylene, which will have a great impact on the health of the sprayers.

[0004] The spray robot can make up for the disadvantages of manual spraying to a large extent with its excellent kinematic control and fast and precise control of spraying process parameters. It can achieve uniform and consistent spraying through automatic planning of paint flow, atomizing air pressure and robot trajectory, effectively avoid overspray, missed spraying and ineffective spraying, improve work efficiency, spraying quality and paint utilization, effectively reduce the waste of manpower and material resources, and avoid direct contact of workers with large amounts of chemical substances.

[0005] At present, domestic spraying robots are composed of robotic arms and spray guns, which can be used for spraying on fixed points or shaped workpiece surfaces. They are unable to automatically inspect, identify, and locate damaged areas on the aircraft surface coating, and it is difficult to achieve in-situ automatic identification and repair of special-shaped and curved coating damage on different parts of the aircraft surface.

[0006] Therefore, it is more important to provide a spraying device for a fixed point or shape workpiece surface. Utility Model Content

[0007] Based on the problems existing in the prior art, the utility model proposes an in-situ automatic repair device for local coating of aircraft, comprising:

[0008] Mobile work platform;

[0009] A 3D camera disposed on the mobile working platform for collecting 2D images and 3D point cloud data of the aircraft surface;

[0010] A repair module installed on a mobile work platform for coating cleaning or paint spraying;

[0011] and a host computer for controlling the mobile working platform, the 3D camera and the repair module.

[0012] On the basis of the above scheme, the mobile working platform comprises:

[0013] A horizontal moving platform connected to the host computer;

[0014] A lifting platform arranged on the horizontal moving platform;

[0015] and a mechanical arm arranged on the lifting platform for driving the 3D camera and the repair module to move.

[0016] Based on the above solution, the repair module includes:

[0017] An automatic spray gun for spraying arranged on the mechanical arm via a mounting seat;

[0018] A paint tank disposed on the horizontal moving platform and connected to the automatic spray gun;

[0019] A spraying electromagnetic valve for opening or closing the automatic spray gun is arranged on the horizontal moving platform and is respectively connected to the paint tank and the automatic spray gun.

[0020] Based on the above solution, the repair module includes:

[0021] Laser cleaning lenses and laser generators for cleaning coatings in damaged areas prior to spraying.

[0022] Based on the above scheme, the host computer is wirelessly connected to the horizontal mobile platform, the robotic arm and the 3D camera to perform human-computer interaction, spray parameter setting, horizontal mobile platform movement control, lifting platform motion control, receiving 2D images and 3D point cloud data transmitted by the 3D camera, damaged area identification and positioning, 3D point cloud real-time processing and posture calculation, path planning and real-time detection of the repair process.

[0023] Compared with the devices of the prior art, the device of the utility model can use the horizontal moving platform and the lifting platform to realize the automatic inspection of the surface damage of the whole machine, and at the same time expand the repair range; in addition, the coordinated control of the robotic arm, high-precision 3D camera, horizontal moving platform, lifting platform and automatic spray gun can realize the in-situ automatic identification and repair of the special-shaped curved coating damage on different parts of the aircraft surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic structural diagram of an in-situ automatic repair device for a local coating of an aircraft according to Embodiment 1 of the utility model;

[0025] Figure 2 This is a structural block diagram of the in-situ automatic repair device for local coating of an aircraft in Example 1 of the utility model;

[0026] Figure 3 This is a schematic diagram of the structure of the laser cleaning part in Example 2 of the utility model;

[0027] Figure 4 This is a schematic diagram of the motion trajectory of the robotic arm in Example 4 of the present utility model. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0029] Example 1

[0030] like Figure 1-2 As shown, the utility model provides an in-situ automatic repair device for local coating of an aircraft, comprising a mobile working platform 10, a 3D camera 20 arranged on the mobile working platform 10 for collecting 2D images and 3D point cloud data of the aircraft surface, a spraying module 30 arranged on the 3D camera 20 for spraying paint, and a host computer 40 for controlling the mobile working platform 10, the 3D camera 20 and the spraying module 30.

[0031] As a specific implementation scheme, the mobile work platform 10 includes a horizontal mobile platform 11, a lifting platform 12 arranged on the horizontal mobile platform 11, and a mechanical arm 13 arranged on the lifting platform 12. Specifically, the horizontal mobile platform 11 is a bearing platform of the in-situ automatic repair device for local coatings of an aircraft, which is wirelessly connected to the host computer 40 and can move according to the planned route and speed. The lifting platform 12 is fixed to the horizontal mobile platform 11 by four bolts, is electrically connected to the horizontal mobile platform 11, is powered by the horizontal mobile platform 11, and is connected to the control cabinet signal of the mechanical arm 13. It can act as the seventh axis to coordinate movement with the mechanical arm 13, and can also accept remote control of the host computer 40 through the control cabinet of the mechanical arm 13 (the mechanical arm control cabinet is a conventional device, mainly used to control the movement of the mechanical arm), and drive the mechanical arm 13 to move up and down. The robotic arm 13 is fixed to the lifting seat on the side of the lifting platform 12 by four bolts. Its control cabinet is installed inside the horizontal moving platform 11 and is powered by the horizontal moving platform 11. It is wirelessly connected to the host computer 40 and can drive the 3D camera 20 and the automatic spray gun 31 to move according to the set speed and planned trajectory.

[0032] As a specific implementation scheme, the 3D camera 20 is fixed to the end of the robotic arm 13 through a bracket, and is used to collect 2D images and 3D point cloud data of the aircraft surface. It is powered by the horizontal moving platform 11 and is wirelessly connected to the host computer 40 to transmit the 2D images and 3D point cloud data to the host computer 40.

[0033] As another implementation scheme of the 3D camera 20, one 3D camera 20 can be replaced by a combination of a coarse positioning 3D camera and a fine positioning 3D camera. The advantage of the coarse positioning 3D camera's large field of view can be used to effectively expand the detection and identification range of damage, and the advantage of the fine positioning 3D camera's high precision can be used to improve the positioning accuracy and thus improve the repair quality. That is, one 3D camera can be used, or two 3D cameras (a coarse positioning 3D camera and a fine positioning 3D camera) can be used. The coarse positioning 3D camera has a large field of view and a large single detection area, while the fine positioning 3D camera has high precision but low accuracy. The combination of the two has the advantage of a single detection area larger than that of a single 3D camera without reducing accuracy.

[0034] As a specific implementation scheme of the spraying module 30, the spraying module 30 includes an automatic spray gun 31, a paint tank 32 connected to the automatic spray gun 31, and a spraying solenoid valve 33 connected to the air outlet of the paint tank 32 and the automatic spray gun 31 respectively for opening or closing the automatic spray gun 31. The automatic spray gun 31 is fixed to the end of the mechanical arm 13 through a mounting seat for paint spraying, and the rear end interface is connected to the paint tank 32 and the spraying solenoid valve 33 through pipelines. The paint tank 32 is fixed on the horizontal moving platform 11, and there are accessories such as a safety valve, a pressure regulating valve, and a stop valve on the paint tank 32. The air inlet of the paint tank 32 is connected to a high-pressure air source (air compressor) through a pipeline, and the discharge port of the paint tank 32 is connected to the automatic spray gun 31 through a pipeline. The air outlet of the paint tank 32 is connected to the spraying solenoid valve 33, and the spraying flow rate can be adjusted by changing the pressure in the tank by the pressure regulating valve. The spray solenoid valve 33 is installed on the horizontal moving platform 11, one end of which is connected to the automatic spray gun 31, and the other end is connected to the air outlet of the paint tank 32. It is connected to the signal of the control cabinet of the robotic arm 13, and can accept the remote control of the upper computer 40 to open and close the automatic spray gun 31 through the control cabinet of the robotic arm 13.

[0035] Specifically, the host computer 40 is wirelessly connected with the horizontal mobile platform 11, the mechanical arm 13, and the 3D camera 20, and can perform human-computer interaction, spray parameter setting, horizontal mobile platform 11 movement control, lifting platform 12 motion control, receiving 2D images and 3D point cloud data transmitted by the 3D camera 20, damaged area identification and positioning, 3D point cloud real-time processing and posture calculation, path planning, and real-time detection of the repair process. As another specific implementation scheme of the control method, wireless data transmission and control can be converted into wired transmission and control through PLC, switches, etc., to meet special requirements such as electromagnetic compatibility and explosion-proof.

[0036] Example 2

[0037] Based on the in-situ automatic repair device for local aircraft coating in Example 1, in actual use, the damaged area needs to be cleaned before spraying, such as Figure 3 As shown, the spray module 30 and its pipeline accessories can be replaced with a laser cleaning lens 51, a laser generator 52 and mounting accessories for cleaning the coating in the damaged area before spraying; in this solution, a laser cleaning part is added to enable it to have the function of cleaning the coating in the damaged area.

[0038] Example 3

[0039] like Figure 1-2 As shown, a method for using an in-situ automatic repair device for a local coating of an aircraft adopts the in-situ automatic repair device for a local coating of an aircraft in Example 1, specifically comprising:

[0040] (1) Provide protection around damaged areas on the aircraft surface to prevent paint from splashing onto intact coatings during spraying;

[0041] (2) The host computer 40 remotely starts the mobile working platform and performs a self-check. The horizontal moving platform 11, the lifting platform 12, the robotic arm 13, the 3D camera 20, the automatic spray gun 31, and the spraying solenoid valve 33 are in the initial state;

[0042] (3) Opening the air supply valve of the high-pressure air source to pressurize the paint tank 32 and supply paint to the automatic spray gun 31;

[0043] (4) The host computer 40 remotely starts the automatic inspection function;

[0044] (5) The horizontal moving platform 11 moves along the planned route, and the lifting platform 12 drives the robot arm 13 and the 3D camera 20 to move up and down;

[0045] (6) The 3D camera 20 collects 2D image data and 3D point cloud data and transmits them to the host computer 40;

[0046] (7) The host computer 40 analyzes the 2D image, identifies the position and quantity of the 2D image of the damaged area, and displays the 2D image position and quantity by number;

[0047] (8) The operator determines the damaged area to be treated according to the number on the upper computer 40 and confirms the spraying moving speed V (500mm / s~900mm / s), spraying distance L1 (200mm~500mm), reserved distance L2 (50mm~150mm), pressure gun distance L3 (5mm~20mm), spacing distance L4 (1mm~10mm), spraying pressure P (0.4MPa~0.8MPa), spraying flow rate W a (0.3MPa~0.8MPa) and other spraying parameters;

[0048] (9) The host computer 40 converts the 2D image position of the damaged area into corresponding 3D point cloud data, and performs coordinate and posture calculation and trajectory planning;

[0049] (10) The host computer 40 transmits the trajectory points to the control cabinet of the robot arm 13;

[0050] (11) The host computer 40 opens the spraying solenoid valve 33 through the robot arm 13 control cabinet;

[0051] (12) The host computer 40 starts the robot arm 13 to move according to the planned path and drives the automatic spray gun 31 to spray;

[0052] (13) After spraying is completed, the spraying solenoid valve 33 is closed and the robot arm 13 returns to the initial position;

[0053] (14) The horizontal mobile platform 11 continues to inspect along the planned route.

[0054] Example 4

[0055] An in-situ automatic repair method for a local coating of an aircraft, using the in-situ automatic repair device for a local coating of an aircraft in Example 1, specifically comprising the following steps:

[0056] S1: Identification and positioning of damaged areas:

[0057] (1) Data compression: The position and related parameters in the received 2D image are used as compression parameters for data processing to reduce the amount of data and improve the data processing speed;

[0058] (2) Data reconstruction: Reconstruct 2D images according to position and related parameters;

[0059] (3) Image enhancement: Enhance the 2D image to improve the contrast of the damaged area in the image;

[0060] (4) Image segmentation: Perform image segmentation on the enhanced 2D image to obtain the boundary of the damaged area;

[0061] (5) Damage localization: Calculate the 2D coordinates of the corresponding pixels based on the damage area boundary and pixel position information;

[0062] (6) Coordinate transformation: Use the 2D-3D transformation matrix of the 3D camera to calculate the 2D coordinates of the damage area boundary corresponding to the 3D point cloud data;

[0063] S2: 3D point cloud processing and pose calculation:

[0064] (1) Construction of spatial coordinate system: The path planning space is constructed with the robot 13 as the base coordinate system, and the 3D point cloud data is transformed from the measurement coordinate system of the 3D camera 20 to the robot base coordinate system;

[0065] (2) Point cloud denoising and smoothing: Use filtering algorithms to remove noise introduced by factors such as the environment, device accuracy, and electromagnetic interference in the 3D point cloud;

[0066] (3) Point cloud simplification: The point cloud data obtained by scanning with the 3D camera 20 is very dense. The data obtained from a single scan usually contains tens of thousands of data points. It is necessary to use a sampling algorithm to compress the original data to improve the efficiency of trajectory planning;

[0067] (4) Point cloud slicing: The intersection slicing method is used to orderly integrate the discrete point clouds according to the gun pressing distance and the interval distance to obtain the trajectory points of the aircraft surface;

[0068] (5) Posture calculation: Calculate the robot arm motion trajectory points based on the aircraft surface trajectory points and spraying parameters;

[0069] S3: Figure 4 As shown, path planning:

[0070] The motion trajectory of the robot arm 13 includes coordinates such as the starting point, the passing point, and the end point. Each point is derived from the surface of the aircraft, and each point has X, Y, Z, R X , R Y , R Z The six coordinate values ​​can control the mechanical arm 13 to drive the automatic spray gun 31 to spray along the curvature of the aircraft surface and maintain the rated distance;

[0071] The motion trajectory of the robot arm 13 is formed by connecting the starting point, the passing point, and the end point in a front-to-back manner. The spraying method is reciprocating spraying, that is, from left to right, and then from right to left. Figure 4 shown.

[0072] Specifically, the calculation formula for the left point (X0, Y0, Z0) of the first row of the motion trajectory of the robot arm 13 is:

[0073] X0=X f1 -L1(1)

[0074] Y0=Y f1 (2)

[0075] Z0=Z f1 +L2(3)

[0076] Among them, X f1 is the X-axis coordinate of the first point in the first row of the damage area, and Y f1 is the Y-axis coordinate of the first point in the first row of the damage area, and Z f1 is the Z-axis coordinate of the first point in the first row of the damage area;

[0077] The first right point of the robot arm motion trajectory (X n+1 , Yn+1 , Z n+1 ) is calculated as:

[0078] X n+1 =X fn +L1(4)

[0079] Y n+1 =Y fn (5)

[0080] Z n+1 =Z fn +L2(6)

[0081] Among them, X fn is the X-axis coordinate of the last point in the first row of the damage area, and Y fn is the Y-axis coordinate of the last point in the first row of the damage area, Z fn is the Z-axis coordinate of the last point in the first row of the damage area;

[0082] The middle point of the first line of the robot arm motion trajectory (X n+1 , Y n+1 , Z n+1 ) is calculated as:

[0083] X i =X fi (i=1、2…n)(7)

[0084] Y i =Y fi (i=1、2…n)(8)

[0085] Z i =Z fi +L2(i=1、2…n)(9)

[0086] Among them, L1 is the reserved distance and L2 is the spraying distance.

[0087] The calculation method of other lines of the robot arm motion trajectory is similar to the first line.

[0088] Here is a specific application example of the in-situ automatic repair method for local coatings on aircraft:

[0089] S1: Identification and positioning of damaged areas:

[0090] (1) Data compression: The K-means algorithm is used to process the data using the position and related parameters in the received 2D image as compression parameters, thereby reducing the amount of data and improving the data processing speed;

[0091] (2) Data reconstruction: Use the K-means algorithm to reconstruct the 2D image according to the position and related parameters;

[0092] (3) Image enhancement: Use the second-order differential algorithm to enhance the 2D image and improve the contrast of the damaged area in the image;

[0093] (4) Image segmentation: The enhanced 2D image is segmented using the particle swarm optimization fuzzy clustering algorithm to obtain the boundary of the damaged area;

[0094] (5) Damage localization: Calculate the 2D coordinates of the corresponding pixels based on the damage area boundary and pixel position information;

[0095] (6) Coordinate transformation: Use the 2D-3D transformation matrix of the 3D camera to calculate the 2D coordinates of the damage area boundary corresponding to the 3D point cloud data;

[0096] S2: 3D point cloud processing and pose calculation:

[0097] (1) Construction of spatial coordinate system: The path planning space is constructed with the robot as the base coordinate system, and the 3D point cloud data is transformed from the 3D camera measurement coordinate system to the robot base coordinate system;

[0098] (2) Point cloud denoising and smoothing: Use the median filter algorithm to remove the noise introduced by factors such as the environment, device accuracy, and electromagnetic interference in the 3D point cloud;

[0099] (3) Point cloud simplification: Use cluster analysis sampling algorithm to compress the original point cloud data and improve trajectory planning efficiency;

[0100] (4) Point cloud slicing: The intersection slicing method is used to orderly integrate the discrete point clouds according to the gun pressing distance L3 (10 mm) and the interval distance L4 (5 mm) to obtain the trajectory points of the aircraft surface;

[0101] (5) Posture calculation: Calculate the robot arm motion trajectory points based on the aircraft surface trajectory points and spraying parameters;

[0102] S3: Path Planning:

[0103] The motion trajectory of the robot arm 13 includes coordinates such as the starting point, the passing point, and the end point. Each point is derived from the surface of the aircraft, and each point has X, Y, Z, R X , R Y , R Z The six coordinate values ​​can control the mechanical arm 13 to drive the automatic spray gun 31 to spray along the curvature of the aircraft surface and maintain the rated distance;

[0104] The motion trajectory of the robot arm is formed by connecting the starting point, the passing point, and the end point. The spraying method is reciprocating spraying, that is, from left to right, and then from right to left:

[0105] The calculation formula for the left point (X0, Y0, Z0) of the first line of the robot motion trajectory is:

[0106] X0=X f1 -80(1)

[0107] Y0=Y f1 (2)

[0108] Z0=Z f1 +100(3)

[0109] The first right point of the robot arm motion trajectory (X n+1 , Y n+1 , Z n+1 )of:

[0110] X n+1 =X fn +80(4)

[0111] Y n+1 =Y fn (5)

[0112] Z n+1 =Z fn +100(6)

[0113] The middle point of the first line of the robot arm motion trajectory (X n+1 , Y n+1 , Z n+1 ) is calculated as:

[0114] X i =X fi (i=1、2…n)(7)

[0115] Y i =Y fi (i=1、2…n)(8)

[0116] Z i =Z fi +400(i=1、2…n)(9)

[0117] In the formula, X f1 is the X-axis coordinate of the first point in the first row of the damage area, and Y f1 is the Y-axis coordinate of the first point in the first row of the damage area, and Z f1 is the Z-axis coordinate of the first point in the first row of the damage area, X fn is the X-axis coordinate of the last point in the first row of the damage area, and Y fn is the Y-axis coordinate of the last point in the first row of the damage area, Z fn is the Z-axis coordinate of the last point in the first row of the damaged area, L1 is the reserved distance, and L2 is the spraying distance.

[0118] The calculation method of other lines of the robot arm motion trajectory is similar to the first line.

[0119] By using the device and method of this embodiment, a high-precision 3D camera is used to realize automatic identification and high-precision positioning of the damaged areas of the irregularly curved coating on the aircraft surface; at the same time, the horizontal moving platform 11 and the lifting platform 12 are used to realize automatic inspection of the surface damage of the whole machine, and at the same time expand the repair range; in addition, the robot arm 12, the high-precision 3D camera 20, the horizontal moving platform 11, the lifting platform 12 and the automatic spray gun 31 are coordinated and controlled to realize the in-situ automatic identification and repair of the damaged areas of the irregularly curved coating on different parts of the aircraft surface.

[0120] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An in-situ automatic repair device for local coating of aircraft, characterized in that: include: Mobile work platform (10); A 3D camera (20) disposed on the mobile working platform (10) for collecting 2D images and 3D point cloud data of the aircraft surface; A repair module (30) arranged on the mobile working platform (10); and a host computer (40) for controlling the mobile working platform (10), the 3D camera (20) and the repair module (30).

2. The in-situ automatic repair device for local aircraft coating according to claim 1 is characterized in that: The mobile working platform (10) comprises: A horizontal moving platform (11) connected to the host computer (40); A lifting platform (12) arranged on the horizontal moving platform (11); and a mechanical arm (13) disposed on the lifting platform (12) and used for driving the 3D camera (20) and the repair module (30) to move.

3. The in-situ automatic repair device for local aircraft coating according to claim 2 is characterized in that: The repair module (30) comprises: An automatic spray gun (31) for spraying, which is arranged on the mechanical arm (13) via a mounting seat; A paint tank (32) disposed on the horizontal movable platform (11) and connected to the automatic spray gun (31); A spraying solenoid valve (33) for opening or closing the automatic spray gun (31) is arranged on the horizontal moving platform (11) and is respectively connected to the paint tank (32) and the automatic spray gun (31).

4. The in-situ automatic repair device for local aircraft coating according to claim 2 is characterized in that: The repair module (30) comprises: A laser cleaning lens (30-1) and a laser generator (30-2) are used for cleaning coatings in damaged areas before spraying.

5. The in-situ automatic repair device for local aircraft coating according to claim 3 is characterized in that: The host computer (40) is wirelessly connected to the horizontal moving platform (11), the mechanical arm (13) and the 3D camera (20).

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