Engine whole machine external assembly quality detection system based on AGV

Abstract

The invention relates to the technical field of engine complete machine external assembly quality detection, in particular to an AGV-based engine complete machine external assembly quality detection system, which comprises a vehicle body, a visual detection device and an electric control system which are separated and independent, and is characterized in that the vehicle body is used for fixing and supporting an engine and is provided with a plurality of fixing clamps; the fixing clamp comprises a stand column, a mounting pin and a pressing block, the bottom of the stand column is fixed to the vehicle body, the pressing block is fixed to the top of the stand column, and the mounting pin is detachably connected with the pressing block; during use, an engine shell is located between the stand columns, and the mounting pins are matched with the engine mounting joints to fix an engine. According to the invention, rapid, accurate and automatic detection of gap assembly quality of fasteners such as aero-engine bolts, nuts, insurance and locking plates and three-dimensional pipelines can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of engine whole machine external assembly quality detection, and in particular to an engine whole machine external assembly quality detection system based on AGV. Background Art

[0002] The external assembly of aircraft engines is complex, with a large number of parts. The number of components is large, the models and specifications are similar, the assembly process is complicated, and wrong installation and missing installation often occur, which seriously affects the quality and efficiency of assembly. Therefore, it is necessary to perform assembly inspection on the external part of the engine.

[0003] At present, the external assembly inspection of aircraft engines is mostly carried out using a variety of high-precision measurement and inspection tools. However, due to the large number of parts, the inspection is time-consuming and labor-intensive, the inspection results are of low accuracy and low efficiency, which in turn affects the assembly efficiency. Summary of the invention

[0004] In view of the problems in the prior art that external inspection of aircraft engines is time-consuming and labor-intensive, and the inspection results are of low accuracy and low efficiency, the present invention provides an engine whole machine external assembly quality inspection system based on AGV.

[0005] The present invention is achieved through the following technical solutions:

[0006] An AGV-based engine whole machine external assembly quality inspection system includes a separate and independent vehicle body, a visual inspection device and an electronic control system. The vehicle body is used to fix and support the engine. The vehicle body is provided with a vehicle body. The vehicle body is provided with a plurality of fixing fixtures. The fixing fixtures include a column, a mounting pin and a clamping block. The bottom of the column is fixed to the vehicle body, the clamping block is fixed to the top of the column, and the mounting pin and the clamping block are detachably connected. When in use, the engine housing is located between the columns, and the mounting pin cooperates with the engine mounting section to fix the engine.

[0007] The visual inspection device includes an AGV mobile trolley, a lifting mechanism, a mechanical arm, a visual inspection system and an obstacle avoidance system. The lifting mechanism is fixed on the AGV mobile trolley. The visual inspection system includes a first industrial camera, a second industrial camera and a laser sensor. The base of the mechanical arm is fixed on the lifting mechanism. The end of the mechanical arm is connected to the housings of the first industrial camera, the second industrial camera and the laser sensor. The first industrial camera is used to identify the coding block on the engine to locate the position of the engine. The second industrial camera is used to collect pictures of the outside of the engine. The laser sensor is used for pipeline gap detection.

[0008] The obstacle avoidance system is set on the outside of the AGV mobile car to avoid obstacles on the driving path; a navigation camera is set at the bottom of the AGV mobile car, and the head of the navigation camera is facing the ground to identify the navigation QR code set on the driving path of the AGV mobile car;

[0009] The electronic control system includes a controller. The driving controller of the vehicle body, the driving controller of the AGV mobile car, the controller of the lifting platform and the driving controller of the robotic arm are all controlled by the controller. The first industrial camera, the second industrial camera and the laser sensor are all connected to the controller. The controller stores a map associated with the navigation QR code.

[0010] Preferably, the distance between the two mounting pins is the distance between the engine mounting nodes.

[0011] Preferably, the lifting mechanism includes a lifting platform, a guide column and a lifting drive component. The guide column is vertically fixed on the AGV mobile cart, the lifting platform is slidably set on the guide column, the driving end of the lifting drive component is connected to the lifting platform, and the base of the robotic arm is fixed on the lifting platform. The lifting platform is driven by the lifting drive component to perform lifting and lowering movements along the guide column, and the start and stop of the lifting drive component is controlled by a controller.

[0012] Preferably, the lifting drive communicates with the controller via an Ethernet bus.

[0013] Preferably, a plurality of navigation QR codes are provided, and each navigation QR code is pre-encoded and associated with map coordinates.

[0014] Preferably, the robotic arm is a six-degree-of-freedom robotic arm.

[0015] Preferably, the electric control system further comprises a human-machine interaction unit, in which operating software is installed for realizing the interaction of operating instructions, emergency stop control and operation status monitoring.

[0016] Preferably, the distance between the AGV mobile vehicle frame and the navigation QR code satisfies the following conditions:

[0017] The barcode spacing Q is greater than the length S of the AGV mobile vehicle;

[0018] The sum of the safety distance L and half of the width A of the AGV mobile vehicle is less than or equal to the barcode width P; wherein the detection safety distance L is greater than or equal to 20 mm.

[0019] Preferably, the obstacle avoidance safety distance M is greater than or equal to 50 mm.

[0020] Preferably, the electronic control system is also configured with a coordinate system, which includes a global coordinate system and a local coordinate system. The global coordinate system includes a robot arm coordinate system, a two-dimensional coordinate system based on a second industrial camera and a three-dimensional coordinate system based on a laser sensor. The local coordinate system is a coordinate system to be detected based on the shape of the engine. During detection, the local coordinate system and the global coordinate system are unified by a common point conversion method to establish the observation point coordinates.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention discloses an AGV-based engine whole machine external assembly quality inspection system. The AGV-based engine whole machine external assembly quality inspection device takes the aircraft engine as the inspection object, uses the AGV omnidirectional mobile platform equipped with a mechanical arm system, and controls multiple visual inspection devices to realize full envelope inspection of the aircraft engine. The mechanical arm is equipped with a visual inspection sensor system to realize the appearance quality inspection of the assembled parts. The overall inspection system has a safety protection function for the engine, achieving high efficiency and high quality inspection performance, and can realize the rapid, accurate and automatic inspection of the assembly quality of the aircraft engine bolts, nuts, insurance, lock pieces and other fasteners and three-dimensional pipeline clearances.

[0023] Furthermore, the present invention uses sensors as an obstacle avoidance system, which can detect obstacles in the surrounding environment in real time. The first industrial camera combined with the navigation QR code on the ground can locate the position of the AGV car to facilitate the planning of the driving path.

[0024] Furthermore, the lifting mechanism is used to realize the mounted robotic arm and drive the robotic arm to move up and down in the vertical direction to facilitate the inspection of the exterior of the engine. When in use, the control system guides the robot to the specified position and performs relevant inspection work within a safe range. The two-dimensional industrial camera is mainly responsible for collecting images of bolts, nuts, fuses, gaskets, locks, etc. on the outside of the engine, and inputs the images into the inspection software to determine the assembly quality of the inspected parts.

[0025] Furthermore, the vehicle body is used to fix and support the engine. While ensuring the safety of engine installation, the vehicle body reduces auxiliary support components as much as possible, reduces obstruction to the engine measurement site, and ensures the openness and safety of the measurement.

[0026] Furthermore, limiting the distance between components can ensure the integrity and safety of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of a vehicle body in the present invention;

[0028] Figure 2 is a schematic diagram of the elevator in the present invention;

[0029] Figure 3 is a schematic diagram of a visual detection device in the present invention;

[0030] Figure 4 Schematic diagram of the visual inspection device for the external assembly quality of the engine measuring the highest point of the engine

[0031] Figure 5Schematic diagram of the visual inspection device for the external assembly quality of the engine measuring the lowest point of the engine

[0032] Figure 6 This is a relationship diagram between the ground QR code and the AGV mobile vehicle in the present invention. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0034] The present invention discloses an engine whole machine external assembly quality inspection system based on AGV, referring to Figure 1 , including a separate and independent car body, a visual inspection device and an electronic control system. The car body is used to fix and support the engine. A car body is provided on the car body. A plurality of fixing fixtures are provided on the car body. The fixing fixtures include a column, a mounting pin and a clamping block. The bottom of the column is fixed to the car body, and the clamping block is fixed to the top of the column. The mounting pin and the clamping block are detachably connected. When in use, the engine housing is located between the columns, and the mounting pin cooperates with the engine mounting section to fix the engine. The distance between the two mounting pins is the distance between the engine mounting sections. In this embodiment, the car body includes a flat plate, a small column and a wheel. The column is fixed above the flat plate, one end of the small column is connected to the bottom of the flat plate, and the other end is connected to the wheel. A rotating shaft is provided at the bottom of the small column for connecting the wheel.

[0035] The visual inspection device includes an AGV mobile trolley, a lifting mechanism, a mechanical arm, a visual inspection system and an obstacle avoidance system. The lifting mechanism is fixed on the AGV mobile trolley. The lifting mechanism includes a lifting platform, a guide column and a lifting drive. The guide column is vertically fixed on the AGV mobile trolley. The lifting platform is slidably arranged on the guide column. The driving end of the lifting drive is connected to the lifting platform. The base of the mechanical arm is fixed on the lifting platform. The lifting platform is driven by the lifting drive to perform lifting and lowering movements along the guide column. The start and stop of the lifting drive is controlled by a controller. In this embodiment, the lifting drive is a cylinder or a hydraulic cylinder.

[0036] The base of the mechanical arm is fixed on the lifting mechanism, and the end of the mechanical arm is connected to the visual detection system. The visual detection system includes a first industrial camera, a second industrial camera and a housing of a laser sensor. The first industrial camera is used to identify the coding block on the engine to locate the position of the engine, the second industrial camera is used to collect pictures of the outside of the engine, and the laser sensor is used for pipeline gap detection. In this embodiment, the mechanical arm adopts a six-degree-of-freedom mechanical arm, the second industrial camera is mounted on the sensor at the end of the mechanical arm, and the control system guides the manipulator to the specified position and performs relevant detection work within a safe range.

[0037] The AGV mobile cart is equipped with an audible and visual alarm device, which can remind you of problems such as guidance failure, obstacles, overturning, and obstacle avoidance. The input end of the audible and visual alarm device is connected to the output end of the sensor and the first industrial camera. The obstacle avoidance system is arranged on the outside of the AGV mobile cart toward the body, and is used to avoid obstacles on the driving path. In this embodiment, the obstacle avoidance system uses a laser sensor, and the laser sensor is arranged at the four corners of the AGV mobile cart. The shell of the navigation camera is fixed on the AGV mobile cart, and the head of the navigation camera faces the ground, which is used to identify the navigation QR code set on the driving path of the AGV mobile cart. There are multiple navigation QR codes, and each navigation QR code is pre-encoded and associated with the map coordinates.

[0038] The electronic control system includes a controller and a human-machine interaction unit. The vehicle body drive controller, the AGV mobile car drive controller, the lifting drive controller and the robot arm drive controller are all controlled by the controller and communicate through the Ethernet bus. It receives the motion instructions of the controller and performs high-precision servo control on all actuators. At the same time, it feeds back the motor's motion speed, position, brake status, temperature and other information to the central controller. The first industrial camera, the second industrial camera and the laser sensor are all connected to the controller, which stores a map associated with the navigation QR code. The controller is the core part of the entire electronic control subsystem and can realize control strategies such as automatic path planning, automatic obstacle avoidance and visual servoing.

[0039] The human-machine interaction unit is installed with operating software for realizing the interaction of operating instructions, emergency stop control, operation status monitoring and alarm functions.

[0040] The electronic control system is also equipped with a coordinate system, which includes a global coordinate system and a local coordinate system. The global coordinate system includes a robot arm coordinate system, a two-dimensional coordinate system based on a second industrial camera, and a three-dimensional coordinate system based on a laser sensor. The local coordinate system is a coordinate system to be detected based on the shape of the engine. During detection, the local coordinate system and the global coordinate system are unified by common point conversion to establish the observation point coordinates.

[0041] Calculate the external dimensions of the engine, AGV omnidirectional mobile platform, lifting mechanism, six-axis freedom robotic arm, and test bench design dimensions and mutual distances to ensure the integrity and safety of the measurement.

[0042] The width of the AGV omnidirectional mobile platform is A, the length is S, and the height is B; the height of the elevator is C (the highest height is C1, the lowest height is C2); the effective length of the robotic arm is D, and the height of the visual inspection system connected to the robotic arm is E; the maximum radial diameter of the engine is ФF; the height of the stand support column is K, and the distance between the two wheels is G; the distance between the AGV's engine external assembly quality visual inspection device and the inspection stand vehicle and the engine is I; the frame platform height is H; the safety distance is L; the barcode width is P, and the left and right barcode spacing is Q.

[0043] 1. Vehicle height B1*AGV width*AGV length A>reserved battery volume + control cabinet volume + navigation device volume + barrier device volume + other parts volume.

[0044] 2. The height B of the AGV vehicle is composed of the vehicle body height B1 and the walking height B2. The walking height B2 = wheel height + shock absorber height + height from the installation plane to the top plane of the shock absorber

[0045] 3. When measuring the highest point of the engine, the height of the lift C1 is:

[0046]

[0047] 4. When measuring the highest point of the engine, the height of the lift C2 is:

[0048]

[0049] 5. The length and width of the lift are smaller than the AGV omnidirectional mobile platform, but larger than the base of the robotic arm.

[0050] 6. AGV engine external assembly quality visual inspection device and test bench vehicle and starting distance I ≥ 50

[0051] 6. Detection safety distance L ≥ 20mm;

[0052] 7. Obstacle avoidance safety distance M ≥ 50mm;

[0053] 8. The distance from the lowest point of the object to be measured to the plane of the platform is N = M + E + L

[0054] 9. The height of the support column K = N + F / 2

[0055] 10. There is no strict requirement for the frame platform height H, which can be designed as B / 2, which is correlated with the height C of the lift, and a reasonable design is sufficient.

[0056] 11. The following restrictions exist between the engine body and the ground QR code:

[0057] (1) The barcode spacing is greater than the length of the AGV mobile vehicle, that is, Q ≥ S (to ensure that the engine transport vehicle will not press the barcode)

[0058] (2) The sum of the safety distance L and half of the width A of the AGV mobile car is less than or equal to the barcode width P, that is, L+A / 2≤P (ensuring that the AGV car can capture the QR code during measurement and does not exceed the range)

[0059] (3) The relationship between the barcode spacing Q and the vehicle length S. The vehicle can capture the highest and lowest points of the engine at the edge of the barcode.

[0060]

[0061] The implementation principle of the AGV-based engine whole machine external assembly quality inspection system of the present invention is:

[0062] (1) Fix the engine on the pillar of the vehicle body;

[0063] (2) The controller drives the driving wheel system of the AGV mobile vehicle to move, and the lifting platform and the robotic arm move synchronously with the AGV mobile vehicle; when the AGV mobile vehicle is moving, the first industrial camera scans the navigation QR code on its driving path and transmits the position of the AGV mobile vehicle to the controller through Ethernet communication; when encountering an obstacle, the sensor transmits a signal to the controller, and the controller changes the driving trajectory of the AGV mobile vehicle by controlling the driving wheel system of the AGV mobile vehicle.

[0064] (3) The controller controls the driving controller of the robot arm to drive the robot arm to move. The second industrial camera collects images of the engine under the drive of the robot arm and transmits the collected image information to the controller for storage and processing. During the inspection, in order to improve the inspection efficiency, the coordinates of the points to be inspected are calibrated in advance. The specific steps are as follows:

[0065] Step 1: Establish and unify the detection system coordinate system (AGV, lifting mechanism diagram, robotic arm, visual sensor);

[0066] Step 2: Establish the aircraft engine coordinate system;

[0067] Step 3: Establish the coordinate system using a single-camera photogrammetry system.

[0068] Taking an aircraft engine as an example, the complete measurement process is as follows: (1) The aircraft engine inspection process is that after the engine enters the designated inspection area and parks stably, the visual system evaluates and locates the engine's entire posture;

[0069] (2) After determining the parking posture of the engine, plan the moving path and the detection item collection path according to the posture position;

[0070] (3) The mobile component equipped with the visual system moves according to the planned path and gradually collects images of the inspection items. The collected images of the inspection items are sent to the inspection system to perform fault detection on the images and generate results that are transmitted to the expert database until all inspection items have been inspected.

[0071] Among them, the pipeline gap detection adopts a laser three-dimensional measurement visual model, and uses a three-dimensional measurement system built with laser and monocular array camera to measure the specific position of the pipeline gap to obtain its three-dimensional data. Through information processing of the data (noise removal, model simplification, model fitting, matching, etc.), the pipeline three-dimensional model is fitted to calculate the minimum pipeline gap. The specific steps are:

[0072] The visual inspection system carried on the robotic arm uses a single camera to capture images and adopts a line structured light band center extraction algorithm to extract the light band center; the extracted light band center is reconstructed in three dimensions, and finally the pipeline is modeled based on the three-dimensional information; then the gap between the pipelines is calculated based on the constructed model.

[0073] Parts quality inspection is combined with artificial intelligence technology. When the robotic arm drives the visual inspection system to the position, it triggers the corresponding CCD lens to take pictures. The measurement is only for single part inspection. The camera collects the actual image of the part. The image information is processed and fed back to the measurement software. The measurement software counts and numbers the measured part images, and makes compliance judgments by comparing with the standard part images stored in the database, measuring or identifying feature parameters.

[0074] (4) After the overall inspection is completed at a certain position, repeat (2) to (3) until the assembly inspection of the entire engine is completed.

[0075] The AGV-based engine whole machine external assembly quality inspection system of the present invention uses a two-dimensional industrial camera to collect images of the engine exterior, and then uses image recognition technology to automatically identify part errors and defects, thereby ensuring the accuracy and reliability of the engine external assembly and providing a strong guarantee for the safe flight of the aircraft.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and substitutions, and these modifications and substitutions are also within the scope of protection covered by the claims.

Claims

1. An AGV-based engine external assembly quality inspection system, characterized in that: It includes a separate and independent car body, a visual inspection device and an electronic control system. The car body is used to fix and support the engine. A plurality of fixing fixtures are arranged on the car body. The fixing fixtures include a column, a mounting pin and a clamping block. The bottom of the column is fixed on the car body, and the clamping block is fixed on the top of the column. The mounting pin and the clamping block are detachably connected. When in use, the engine housing is located between the columns, and the mounting pin cooperates with the engine mounting section to fix the engine. The visual inspection device includes an AGV mobile trolley, a lifting mechanism, a mechanical arm, a visual inspection system and an obstacle avoidance system. The lifting mechanism is fixed on the AGV mobile trolley. The visual inspection system includes a first industrial camera, a second industrial camera and a laser sensor. The base of the mechanical arm is fixed on the lifting mechanism. The end of the mechanical arm is connected to the housings of the first industrial camera, the second industrial camera and the laser sensor. The first industrial camera is used to identify the coding block on the engine to locate the position of the engine. The second industrial camera is used to collect pictures of the outside of the engine. The laser sensor is used for pipeline gap detection. The obstacle avoidance system is installed on the AGV mobile vehicle to avoid obstacles on the driving path; A navigation camera is set at the bottom of the AGV mobile car, and the head of the navigation camera is facing the ground, which is used to identify the navigation QR code set on the driving path of the AGV mobile car; The electronic control system includes a controller. The driving controller of the vehicle body, the driving controller of the AGV mobile car, the controller of the lifting platform and the driving controller of the robotic arm are all controlled by the controller. The first industrial camera, the second industrial camera and the laser sensor are all connected to the controller. The controller stores a map associated with the navigation QR code.

2. The AGV-based engine whole machine external assembly quality inspection system according to claim 1 is characterized in that: The distance between the two mounting pins is the distance between the engine mounting sections.

3. The AGV-based engine whole machine external assembly quality inspection system according to claim 1 is characterized in that: The lifting mechanism includes a lifting platform, a guide column and a lifting drive component. The guide column is vertically fixed on the AGV mobile cart, the lifting platform is slidably set on the guide column, the driving end of the lifting drive component is connected to the lifting platform, and the base of the robotic arm is fixed on the lifting platform. The lifting platform is driven by the lifting drive component to perform lifting and lowering movements along the guide column, and the start and stop of the lifting drive component is controlled by the controller.

4. The AGV-based engine whole machine external assembly quality inspection system according to claim 1 is characterized in that: The lifting drive communicates with the controller via the Ethernet bus.

5. The AGV-based engine whole machine external assembly quality inspection system according to claim 1 is characterized in that: There are multiple navigation QR codes, each of which is pre-encoded and associated with map coordinates.

6. The AGV-based engine whole machine external assembly quality inspection system according to claim 1, characterized in that: The robotic arm adopts a six-degree-of-freedom robotic arm.

7. The AGV-based engine whole machine external assembly quality inspection system according to claim 1 is characterized in that: The electric control system also includes a human-machine interaction unit, in which operating software is installed for realizing the interaction of operating instructions, emergency stop control and operation status monitoring.

8. The AGV-based engine whole machine external assembly quality inspection system according to claim 1 is characterized in that: The distance between the AGV mobile car frame and the navigation QR code must meet the following requirements: The barcode spacing Q is greater than the length S of the AGV mobile vehicle; The sum of the safety distance L and half of the width A of the AGV mobile vehicle is less than or equal to the barcode width P; wherein the detection safety distance L is greater than or equal to 20 mm.

9. The AGV-based engine whole machine external assembly quality inspection system according to claim 1, characterized in that: The obstacle avoidance safety distance M is greater than or equal to 50 mm.

10. The AGV-based engine whole machine external assembly quality inspection system according to claim 1, characterized in that: The electronic control system also includes a coordinate system, which includes a global coordinate system and a local coordinate system. The global coordinate system includes a robot arm coordinate system, a two-dimensional coordinate system based on a second industrial camera, and a three-dimensional coordinate system based on a laser sensor. The local coordinate system is a coordinate system to be detected based on the shape of the engine. During detection, the local coordinate system and the global coordinate system are unified by common point conversion to establish the observation point coordinates.

Images