Intelligent detection method for redundant objects in narrow and semi-closed area of airplane

Abstract

The invention belongs to the technical field of aircraft assembly detection, and relates to an intelligent detection method for redundant objects in a narrow semi-closed area of an aircraft. The narrow semi-closed area redundancy detector is used for detecting the redundancy in the narrow semi-closed area, the automatic detection of the redundancy in the narrow semi-closed area is realized by constructing a deep learning network, the reliability and accuracy of the system are improved, the economic loss caused by misoperation due to the high and low level of an inspector is avoided, and the detection efficiency is improved. The method has the advantages that time wasted by repeated detection is shortened, economic losses caused by reworking, repairing and product out-of-tolerance are reduced, the accuracy of the detection quality of the redundant objects in the narrow semi-closed area is remarkably improved, meanwhile, the production efficiency of products can be improved, and the method plays a positive role in guaranteeing the quality of airplanes.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft assembly detection, and relates to an intelligent detection method for redundant objects in a narrow semi-enclosed area of ​​an aircraft. Background Art

[0002] Redundant objects refer to materials in parts, components and complete products that are irrelevant to product drawings and specifications. Redundant objects may enter from the outside or be generated from the inside. In the aviation field, redundant objects are one of the important causes of low-level quality accidents of aircraft, which brings many serious hazards to flight safety. Excess objects in a narrow and semi-enclosed area refer to the fact that the inside of the narrow and semi-enclosed area has not been cleaned properly during the assembly process, assembly and delivery, inspection and maintenance of the aircraft due to subjective and objective factors such as construction workers rushing to meet deadlines, negligence or inspection difficulties, resulting in a large number of foreign debris fragments that threaten flight safety. In addition to metal debris and construction tools, these foreign debris also include sealing rubber particles, fuses, screws and nuts and other assembly accessories. If these excess objects are in the narrow and semi-enclosed area of ​​the air inlet, they are likely to enter the engine due to vibration during flight, causing the air inlet to be blocked, the aircraft engine to fail or even stall in the air during flight; if these excess objects are in the narrow and semi-enclosed area of ​​the cockpit, they are likely to affect the use of the control system during flight; if these excess objects are in the narrow and semi-enclosed area of ​​the center wing, they are likely to block the pipelines and affect the fuel supply system, which may cause serious flight accidents and immeasurable losses.

[0003] At present, the main inspection methods for excess objects in small and semi-enclosed areas in the industry are visual inspection and endoscopic inspection. Both inspection methods are highly dependent on the inspector, which is not only inefficient, but also has high inspection intensity and difficulty. Different inspection postures need to be changed, but it is also impossible to achieve full coverage inspection of small and semi-enclosed areas. Excess objects in the visual blind spot cannot be fully detected, and the inspection accuracy is relatively low. There is no reliable solution to the problem of how to efficiently and accurately inspect excess objects in small and semi-enclosed areas with the existing technology. Therefore, there is an urgent need for a detector for excess objects in small and semi-enclosed areas and a method for using it. Summary of the invention

[0004] The present invention aims to provide on-site inspectors with a detection instrument and a method for use for inspecting narrow and semi-enclosed areas of aircraft. By constructing a deep learning network, the present invention automatically compares whether there are redundant objects by taking pictures, and uses a slide group structure to achieve multi-angle shooting of pictures, so as to solve the problems in the above technical background.

[0005] The technical solution of the present invention is as follows:

[0006] The deep learning method for detecting redundant objects in a narrow semi-enclosed area is as follows:

[0007] The first step is preparation. Connect the display screen to the control unit, load the data set, prepare 30,000 training images and 5,000 test images. The training set comes from the images of the narrow semi-enclosed area of ​​the aircraft that has reached the final state. The test set of 5,000 images has 2,500 images from the narrow semi-enclosed area of ​​the aircraft that has reached the final state, and 2,500 images from the narrow semi-enclosed area of ​​the aircraft that has completed all assembly work. Each image is 28×28 pixels. The data set will convert the data of a picture into a one-dimensional vector of 28×28=784 and store it. Put the collected 30,000 training images into the training data set, and put the 5,000 images prepared for testing into the test data set.

[0008] Secondly, code writing, debugging, modification and testing. The first step is to load the data set, that is, the collected training data set and test data set. The second step is to build the model. The model is mainly composed of two convolutional layers, two pooling layers, and three connection layers. The relu activation function, the loss function CrossentropyLoss, and the linear classification model Softmax are used to give the final prediction value for the probability of 10 categories. Log converts multiplication into addition to reduce the amount of calculation and ensure the monotonicity of the function. NLLLoss calculates the loss and completes it automatically. The third step is model training. Input is the input data and target is the label. Through model prediction, gradient clearing, back propagation and parameter update, the model is saved every 100 times and the loss is printed. The fourth step is to load the model. Through the total number and the number of correct predictions, the matrix target is used to use size to take out the size of the batch, sum to find the equal number, and then print out the test accuracy. The fifth step is to test image recognition. Load the trained model and run the program for about 14 rounds. The loss value is 0.7902% and the accuracy is 99.0308%.

[0009] Finally, the code is implanted into the controller to complete the construction of the deep learning method for the redundant object images in the narrow semi-enclosed area. The specific process is as follows: Figure 1 shown.

[0010] The micro HD camera shooting path algorithm is as follows:

[0011] 1) Check the digital model of the narrow semi-enclosed area and use simulation software to simulate the shooting path, shooting angle, and shooting times;

[0012] 2) Test the simulated shooting on the real object in a small semi-enclosed area;

[0013] 3) The shooting path, shooting angle and shooting times are implanted into the control system in accordance with the expected requirements.

[0014] The slide group consists of two micro slides to achieve four degrees of freedom. The micro slide consists of a stepper motor, a bearing sheet, a T-type lead screw, a slider, a linear rail, and a motor flange. Figure 2 As shown in the figure, the stepper motor drives the slider to make linear motion on the linear rail through the T-type lead screw.

[0015] The technical problem solved by the present invention is achieved by adopting the following technical solutions:

[0016] The present invention designs a small and semi-enclosed area excess object detector, which is used to realize the detection of excess objects in a narrow and semi-enclosed area. By constructing a deep learning network, automatic detection of excess objects in a narrow and semi-enclosed area can be realized, thereby improving the reliability and accuracy of the system, getting rid of the economic losses caused by misoperation due to the high and low levels of inspectors, reducing the time wasted in repeated inspections, reducing the economic losses caused by rework and repair and product out-of-tolerance, and significantly improving the accuracy of the detection quality of excess objects in a narrow and semi-enclosed area. At the same time, the production efficiency of the product can also be improved, which plays a positive role in ensuring the quality of aircraft.

[0017] A detector for detecting excess objects in a narrow semi-enclosed area, comprising a suction cup, a suction cup switch, an M5 bolt, an L-shaped bracket A, an electric push rod with a stepping motor, an L-shaped bracket B, a stepping motor, a coupling, an L-shaped bracket C, a micro slide set, a micro high-definition camera, a control console, a display screen, a drive system, a control system, a switch button, a reset button, an alarm, and an electric push rod regulator for zone I.

[0018] The suction cup is fixed on the outer skin of the narrow semi-enclosed area by adjusting the suction cup switch. The L-shaped bracket A is fixed on the suction cup by M5 bolts. The electric push rod with a stepper motor is fixed on the L-shaped bracket A by M4 bolts. The distance of the electric push rod with a stepper motor is adjusted so that the L-shaped bracket B is in the narrow semi-enclosed area. The electric push rod with a stepper motor is fixed on the L-shaped bracket B by 4 M3 bolts. The electric push rod with a stepper motor is fixed on the other end of the L-shaped bracket B, and the depth of the electric push rod entering the narrow semi-enclosed area is adjusted by the motor. The stepper motor is fixed on the other end of the electric push rod with a stepper motor, and the other end of the stepper motor is connected to the coupling. The other end of the coupling is connected to the L-shaped bracket C, and the coupling is controlled by the stepper motor to drive the L-shaped bracket C to rotate. The electric push rod with a stepper motor on the left side of the L-shaped bracket C adjusts the lateral distance of the electric push rod entering the narrow semi-enclosed area by the motor. The other end of the electric push rod with a stepper motor is fixed with a micro slide assembly, the micro slide assembly is composed of 2 micro slides, and a micro high-definition camera is installed on the micro slide assembly.

[0019] The electric control component is an important element to realize the redundant function. The detection instrument uses 3 electric push rods with stepper motors and 2 sliders, 2 of which are large thrust electric push rods. The distribution area of ​​the electric push rods with stepper motors is as follows: Figure 5As shown, the electric push rod with stepper motor in zone I is used to adjust the distance between the narrow semi-enclosed area and the suction cup, the electric push rod with stepper motor in zone II is used to adjust the depth of the narrow semi-enclosed area, with a thrust of 200N and a stroke of 0-100mm, and the electric push rod with stepper motor in zone III is a small thrust electric push rod, which is used to realize the telescopic positioning of the redundant object detection instrument in the spatial position of the X axis, with a thrust of 100N and a stroke of 0-200mm. The micro-high-definition camera is fixed on the micro-slide group to realize the telescopic positioning of the redundant object detection instrument in the spatial position of the Y axis and the Z axis. The micro-slide group can move the micro-high-definition camera to the corner position of the narrow semi-enclosed area. The device uses 6 motors, of which the motors in zones I and II are high-torque motors to control the distance of the electric push rods. In addition, the stepper motor and the two motors of the micro-slide group are small-torque motors. The stepper motor is used to realize the rotation of the detection instrument, and the two motors of the micro-slide group are used to realize the precise movement of the micro-high-definition camera. Through the instructions issued by the external control system, a total of 8 actuators (including 3 electric telescopic rods with stepper motors, 2 sliders of the micro slide group, and 3 stepper motors) are controlled to coordinate actions to achieve the 6-degree-of-freedom spatial positioning of the miniature high-definition camera, which meets the needs of detecting unnecessary objects in small semi-enclosed areas.

[0020] The micro high-definition camera is the sensing component of the detection instrument. It is fixed on the micro slide group. It takes pictures through the received data information and transmits them to the control system for processing. In the early stage, by checking the theoretical structure and position of the digital model and combining the shooting test of the narrow and semi-enclosed area of ​​the real object, it is finally determined that the narrow semi-enclosed area can switch the path 7 times and shoot a total of 36 times to achieve accurate judgment of the detection of excess objects. The accurate route control program is implanted into the control system. At the same time, by manually adjusting the electric push rod adjuster of Zone I, the micro high-definition camera can complete the shooting. The control system uses deep learning methods to automatically compare and determine whether there are excess objects. If there are excess objects, the alarm of the control system flashes and an alarm sounds, and the display screen shows that there are excess objects in a certain area to facilitate the subsequent removal of excess objects.

[0021] The intelligent detection method for redundant objects in a small semi-enclosed area of ​​an aircraft has the following steps:

[0022] Step 1: Preparation work, check the appearance quality and circuit of the small semi-enclosed area excess object detector to see if it is intact; install the suction cup on the outer skin of the small semi-enclosed area through the suction cup switch, and confirm that the entire device is firmly installed without shaking;

[0023] Step 2: Use the suction cup switch to install the suction cup on the outer skin of the narrow semi-enclosed area to confirm that the entire testing instrument is installed firmly without shaking;

[0024] Step 3: Turn on the power of the console and manually adjust the electric push rod adjuster in zone I so that the L-shaped bracket B is at the opening of the narrow semi-enclosed area;

[0025] Step 4: Press the reset button on the console, then press the switch button. The micro HD camera will shoot along the predetermined path. If any extra objects are found, the alarm will flash and sound, and the area where the extra objects are found will be displayed on the screen.

[0026] Step 5: Record by area whether there are any extra items in the small semi-enclosed area;

[0027] Step 6: Press the switch button on the console to turn off the power, and remove the detection instrument using the suction cup switch.

[0028] The present invention has the following advantages:

[0029] During the product production process, by implementing the above-mentioned method for detecting excess objects in narrow and semi-enclosed areas of aircraft and using a special excess object detector, the detection rate and detection accuracy can be effectively improved, the economic losses caused by traditional methods can be reduced, the detection method can be improved, the time wasted on repeated detection can be reduced, and the accuracy of quality control in narrow and semi-enclosed areas can be significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a flow chart of the deep learning construction method of redundant object images in small semi-enclosed areas;

[0031] Figure 2 It is the structural diagram of the micro slide;

[0032] Figure 3 It is an axonometric diagram of the redundant object detector in a narrow semi-enclosed area;

[0033] Figure 4 It is a schematic diagram of the control console of the redundant object detector in a small semi-enclosed area;

[0034] Figure 5 This is the distribution diagram of an electric linear actuator with a stepper motor.

[0035] Among them, 1-suction cup, 2-suction cup switch, 3-M5 bolt, 4-L-type bracket A, 5-electric push rod with stepper motor, 6-L-type bracket B, 7-stepper motor, 8-coupling, 9-L-type bracket C, 10-micro slide group, 11-micro HD camera, 12-console, 13-display screen, 14-drive system, 15-control system, 16-switch button, 17-reset button, 18-alarm, 19-electric push rod regulator for zone I. DETAILED DESCRIPTION

[0036] Embodiment 1:

[0037] A detector for detecting excess objects in a narrow semi-enclosed area, comprising a suction cup 1, a suction cup switch 2, an M5 bolt 3, an L-shaped bracket A4, an electric push rod 5 with a stepping motor, an L-shaped bracket B6, a stepping motor 7, a coupling 8, an L-shaped bracket C9, a micro slide group 10, a micro high-definition camera 11, a control console 12, a display screen 13, a drive system 14, a control system 15, a switch button 16, a reset button 17, an alarm 18 and an electric push rod regulator 19 for zone I.

[0038] The suction cup 1 is fixed on the outer skin of the narrow semi-enclosed area by adjusting the suction cup switch 2. The L-shaped bracket A4 is fixed on the suction cup 1 by the M5 bolt 3. The electric push rod 5 with the stepper motor is fixed on the L-shaped bracket A4 by the M4 bolt. The distance of the electric push rod 5 with the stepper motor is adjusted so that the L-shaped bracket B6 is in the narrow semi-enclosed area. The electric push rod 5 with the stepper motor is fixed on the L-shaped bracket B6 by four M3 bolts. The electric push rod 5 with the stepper motor is fixed on the other end of the L-shaped bracket B6, and the depth of the electric push rod 5 entering the narrow semi-enclosed area is adjusted by the motor. The other end of the electric push rod 5 with the stepper motor is fixed to the stepper motor 7, and the other end of the stepper motor 7 is connected to the coupling 8. The other end of the coupling 8 is connected to the L-shaped bracket C9, and the coupling 8 is controlled by the stepper motor 7 to drive the L-shaped bracket C9 to rotate. The electric push rod 5 with the stepper motor on the left side of the L-shaped bracket C9 adjusts the lateral distance of the electric push rod 5 entering the narrow semi-enclosed area by the motor. The other end of the electric push rod 5 with a stepper motor is fixed with a micro slide assembly. The micro slide assembly 10 is composed of two micro slides, and a micro high-definition camera 11 is installed on the micro slide assembly 10.

[0039] The electric control component is an important element to realize the redundant function. The detection instrument uses 3 electric push rods with stepper motors and 2 sliders, 2 of which are large thrust electric push rods. The distribution area of ​​the electric push rods with stepper motors is as follows: Figure 5As shown, the electric push rod 5 with a stepper motor in zone I is used to adjust the distance between the narrow semi-enclosed area and the suction cup, the electric push rod 5 with a stepper motor in zone II is used to adjust the depth of the narrow semi-enclosed area of ​​the goal, with a thrust of 200N and a stroke of 0-100mm, and the electric push rod 5 with a stepper motor in zone III is a small thrust electric push rod, which is used to realize the telescopic positioning of the redundant object detection instrument in the spatial position X axis, with a thrust of 100N and a stroke of 0-200mm, and a micro high-definition camera 11 is fixed on the micro slide group 10, which is used to realize the telescopic positioning of the redundant object detection instrument in the spatial position Y axis and Z axis. The micro high-definition camera 11 can be moved to the corner position of the narrow semi-enclosed area through the micro slide group. The device uses 6 motors, of which the motors in Zone I and Zone II are high-torque motors to control the distance of the electric push rod. In addition, the stepper motor 13 and the two motors in the micro-slide group are low-torque motors. The stepper motor 7 is used to realize the rotation of the detection instrument, and the two motors in the micro-slide group are used to realize the precise movement of the micro-HD camera 11. Through the instructions issued by the external control system, the three electric telescopic rods with stepper motors, the two sliders of the micro-slide group, the two motors of the three stepper motor micro-slide group, and the stepper motor 7, a total of 8 actuators, are controlled to coordinate actions to realize the spatial 6-DOF positioning of the micro-HD camera 11, meeting the detection of redundant objects in a narrow semi-enclosed area.

[0040] The micro high-definition camera 11 is the sensing component of the detection instrument, which is fixed on the micro slide group 10. It takes pictures through the received data information and transmits them to the control system for processing. In the early stage, by checking the theoretical structure and position of the digital model and combining the shooting test of the narrow and semi-enclosed area of ​​the real object, it is finally determined that the narrow semi-enclosed area switches the path 7 times and shoots a total of 36 times to achieve accurate judgment of the detection of excess objects. The accurate route control program is implanted in the control system. At the same time, by manually adjusting the electric push rod adjuster 19 of zone I, the micro high-definition camera 11 can complete the shooting. The control system uses deep learning methods for automatic comparison to determine whether there are excess objects. If there are excess objects, the alarm 18 of the control system flashes and sounds an alarm, and the display screen 13 shows that there are excess objects in a certain area to facilitate the subsequent removal of excess objects.

[0041] Embodiment 2:

[0042] The intelligent detection method for redundant objects in a small semi-enclosed area of ​​an aircraft has the following steps:

[0043] Step 1: Preparation work, check the appearance quality and circuit of the small semi-enclosed area excess object detector to see if it is intact; install the suction cup 1 on the outer skin of the small semi-enclosed area through the suction cup switch 2, and confirm that the entire device is firmly installed without shaking;

[0044] Step 2: Use the suction cup switch 2 to install the suction cup 1 on the outer skin of the narrow semi-enclosed area, and make sure that the entire testing instrument is installed firmly without shaking;

[0045] Step 3: Turn on the power of the console and manually adjust the electric push rod adjuster 19 in zone I so that the L-shaped bracket B6 is at the opening of the narrow semi-enclosed area;

[0046] Step 4: Press the console reset button 17, then press the switch button 16, the micro HD camera 11 takes pictures along the predetermined path, if excess objects are found, the alarm 18 flashes and sounds an alarm, and the display screen 13 shows the area where the excess objects are present;

[0047] Step 5: Record by area whether there are any extra items in the small semi-enclosed area;

[0048] Step 6: Press the console switch button 16 to turn off the power supply, and remove the detection instrument through the suction cup switch 2.

Claims

1. A detector for detecting excess objects in a narrow semi-enclosed area, characterized in that: It includes a suction cup (1), a suction cup switch (2), an M5 bolt (3), an L-shaped bracket A (4), an electric push rod with a stepping motor (5), an L-shaped bracket B (6), a stepping motor (7), a coupling (8), an L-shaped bracket C (9), a micro slide set (10), a micro high-definition camera (11), a control console (12), a display screen (13), a drive system (14), a control system (15), a switch button (16), a reset button (17), an alarm (18) and an electric push rod regulator for zone I (19); The suction cup (1) is fixed on the outer skin of the narrow semi-enclosed area by adjusting the suction cup switch (2); the L-shaped bracket A (4) is fixed on the suction cup (1) by M5 bolts (3); the electric push rod (5) with a stepper motor is fixed on the L-shaped bracket A (4) by M4 bolts; the distance of the electric push rod (5) with a stepper motor is adjusted so that the L-shaped bracket B (6) is located in the narrow semi-enclosed area; the electric push rod (5) with a stepper motor is fixed on the L-shaped bracket B (6) by four M3 bolts; the other end of the L-shaped bracket B (6) is fixed with the electric push rod (5) with a stepper motor, and the depth of the electric push rod (5) entering the narrow semi-enclosed area is adjusted by the motor. ; The other end of the electric push rod (5) with a stepper motor is fixed to the stepper motor (7), the other end of the stepper motor (7) is connected to the coupling (8), the other end of the coupling (8) is connected to the L-shaped bracket C (9), and the coupling (8) is controlled by the stepper motor (7) to drive the L-shaped bracket C (9) to rotate; the electric push rod (5) with a stepper motor is on the left side of the L-shaped bracket C (9), and the lateral distance of the electric push rod (5) entering the narrow semi-enclosed area is adjusted by the motor; the other end of the electric push rod (5) with a stepper motor is fixed to a micro slide assembly, the micro slide assembly (10) is composed of two micro slides, and the micro high-definition camera (11) is installed on the micro slide assembly (10).

2. The detector for detecting excess objects in a narrow semi-enclosed area as claimed in claim 1, characterized in that: The electric push rod (5) with a stepper motor in zone I is used to adjust the distance between the narrow semi-enclosed area and the suction cup, and the electric push rod (5) with a stepper motor in zone II is used to adjust the depth of the narrow semi-enclosed area of ​​the goal, with a thrust of 200N and a stroke of 0-100mm; the electric push rod (5) with a stepper motor in zone III is a small-thrust electric push rod, which is used to realize the telescopic positioning of the excess object detection instrument in the spatial position X-axis, with a thrust of 100N and a stroke of 0-200mm.

3. A detector for detecting excess objects in a narrow semi-enclosed area as claimed in claim 1 or 2, characterized in that: A miniature high-definition camera (11) is fixed on the miniature slide group (10) to realize the telescopic positioning of the excess object detection instrument in the Y-axis and Z-axis of the space position.

4. A detector for detecting excess objects in a narrow semi-enclosed area as claimed in claim 1 or 2, characterized in that: The external stepper motor (13) and the two motors of the micro slide group (10) are small torque motors. The stepper motor (7) is used to realize the rotation of the detection instrument, and the two motors of the micro slide group are used to realize the precise movement of the micro high-definition camera (11).

5. The detector for detecting excess objects in a narrow semi-enclosed area as claimed in claim 3, characterized in that: The external stepper motor (13) and the two motors of the micro slide group (10) are small torque motors. The stepper motor (7) is used to realize the rotation of the detection instrument, and the two motors of the micro slide group are used to realize the precise movement of the micro high-definition camera (11).

6. A detector for detecting excess matter in a narrow semi-enclosed area as claimed in claim 1, 2 or 5, characterized in that: The micro high-definition camera (11) is fixed on the micro slide group (10), and takes pictures based on the received data information and transmits them to the control system for processing.

7. The apparatus for detecting excess matter in a narrow semi-enclosed area as claimed in claim 35, characterized in that: The micro high-definition camera (11) is fixed on the micro slide group (10), and takes pictures based on the received data information and transmits them to the control system for processing.

8. The apparatus for detecting excess matter in a narrow semi-enclosed area as claimed in claim 4, characterized in that: The micro high-definition camera (11) is fixed on the micro slide group (10), and takes pictures based on the received data information and transmits them to the control system for processing.

9. The intelligent detection method for redundant objects in a narrow semi-enclosed area of ​​an aircraft according to any one of claims 1 to 8, characterized in that: Here are the steps: Step 1: Preparation work, check the appearance quality and circuit of the small semi-enclosed area excess object detector to see if it is intact; install the suction cup (1) on the outer skin of the small semi-enclosed area through the suction cup switch (2), and confirm that the entire device is firmly installed without shaking; Step 2: Use the suction cup switch (2) to install the suction cup (1) on the outer skin of the narrow semi-enclosed area, and confirm that the entire testing instrument is installed firmly without shaking; Step 3: Turn on the power of the control console and manually adjust the electric push rod adjuster (19) of zone I so that the L-shaped bracket B (6) is located at the opening of the narrow semi-enclosed area; Step 4: Press the console reset button (17), then press the switch button (16), the micro high-definition camera (11) takes pictures along the predetermined path, if excess objects are found, the alarm (18) flashes and sounds an alarm, and the display screen (13) shows the area where the excess objects are present; Step 5: Record by area whether there are any extra items in the small semi-enclosed area; Step 6: Press the console switch button (16) to turn off the power supply, and remove the detection instrument through the suction cup switch (2).

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