A Potentiometer Adjustment Hole Locating Method Based on Force Feedback Rectangular Search Strategy

Abstract

This invention relates to the field of debugging and testing technology for airborne equipment, specifically a method for locating potentiometer adjustment holes based on a force feedback rectangular search strategy. The method includes the following steps: S1, hole error analysis; S2, force analysis; S3, hole-finding strategy design; S4, specific hole-finding process. This invention provides a method for locating potentiometer adjustment holes based on a force feedback rectangular search strategy. Compared with existing technologies, without increasing hardware investment or significantly increasing system computation, it improves the hole-finding accuracy from 80.8% to 98.3%, enhancing the overall efficiency of the automatic debugging system. Furthermore, during the hole-finding process, the contact force between the screwdriver and the potentiometer adjustment knob panel is always kept within a set safety threshold range, preventing damage to the potentiometer.

Description

Technical Field

[0001] This invention relates to the field of airborne equipment debugging and testing technology, specifically a potentiometer adjustment hole finding method based on a force feedback rectangular search strategy. Background Technology

[0002] Fly-by-wire control is one of the hallmarks of third-generation fighter jets. Its core computing component, the fly-by-wire computer, is responsible for calculating and converting the aircraft's control laws. Analog fly-by-wire computers use adjustable potentiometers to adjust and compensate for the control laws. During major aircraft overhauls, it is necessary to adjust and test the performance parameters of the fly-by-wire control system by adjusting the potentiometers. Because the space on board displays the small size of the fly-by-wire computer potentiometers and their adjustment holes, manual adjustment was often used in the early stages, which was inefficient and inconsistent.

[0003] Chinese patent CN202210319684.6 (publication date: March 15, 2024) discloses an automatic adjustment method for a fly-by-wire computer potentiometer. This method uses a vision system to acquire images of the potentiometer and performs image processing to determine the position coordinates of the potentiometer adjustment hole in a visual coordinate system. Then, by transforming the visual coordinate system into a robotic arm coordinate system, the potentiometer adjustment hole is located. However, due to inherent mechanical errors in the system and errors in the visual algorithm, the accuracy of the device's shaft-hole fit is low, resulting in a low success rate in finding the hole.

[0004] Chinese patent CN201810904192.7 (publication date: January 12, 2021) discloses a positioning method based on a four-lens visual positioning system. This system comprises four parallel CCD cameras, forming six pairs of binocular visual positioning systems. Multiple sets of spatial coordinate data for the measured point are acquired through these systems, and the optimal spatial coordinate data for the measured point is obtained from these sets, thereby improving the positioning accuracy. However, this method increases the amount of hardware required, and the acquisition and processing of multiple sets of images increases the system's data processing burden. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a potentiometer adjustment hole locating method based on a force feedback rectangular search strategy.

[0006] The technical problem to be solved by this invention is achieved by the following technical solution:

[0007] A method for locating potentiometer adjustment holes based on a force feedback rectangular search strategy includes a vision system. The specific steps of the vision system for hole location are as follows:

[0008] S1. Manhole Error Analysis:

[0009] Based on the dimensions of the adjustment hole on the potentiometer and the tip size of the flathead screwdriver in the vision system, a modeling analysis is performed: After the flathead screwdriver in the vision system reaches the target point for coarse positioning, three situations may occur: deviation on the X-axis, deviation on the Y-axis, and deviation on both the X and Y axes. This will cause the flathead screwdriver to contact the edge of the adjustment hole on the potentiometer, generating a contact force in the Z-axis direction of the six-dimensional sensor in the vision system, i.e., it will be subjected to a force F in the opposite direction. z ;

[0010] S2, Force Analysis:

[0011] Establish a force model and perform force analysis: When the tip of the flathead screwdriver does not contact the potentiometer surface, the six-dimensional sensor on the vision system is not subjected to force in the Z-axis direction. z The value is zero when the flathead screwdriver comes into contact with the potentiometer surface. z The potentiometer generates and rapidly increases in a vertically upward direction. If a flathead screwdriver is inserted downwards while the potentiometer is in this state, it will damage the potentiometer. A stop threshold F is set based on the force analysis results. Zthreshold The stopping threshold F will be set. Zthreshold As a trigger condition for the flathead screwdriver to stop moving downwards;

[0012] S3. Hole-finding strategy design:

[0013] Based on the characteristics of the adjustment hole on the potentiometer, a rectangular trajectory search strategy is adopted, with the search direction from the inside out;

[0014] S4. Detailed hole-finding process:

[0015] The computer in the vision system controls the robotic arm to move a flathead screwdriver via a connecting cable. When the screwdriver contacts the edge of the adjustment hole on the potentiometer, it detects F. z Rapidly increase until the preset stopping threshold F is reached. Zthreshold The screwdriver immediately stops its downward movement, maintaining contact with the slotted screwdriver and searching for the hole according to a rectangular trajectory search strategy. When F is detected... z When the value is zero, it means that the flathead screwdriver is no longer in contact with the edge of the adjustment hole on the potentiometer. At this time, the flathead screwdriver is inside the adjustment hole on the potentiometer, which means that the hole finding was successful, and the flathead screwdriver stops its hole finding movement.

[0016] As a further improvement of the present invention, the vision system includes a base, a computer, a robotic arm mounted on the base, and a potentiometer bracket. The end of the robotic arm is provided with a camera, a light source, a lens, a six-dimensional sensor, and a flathead screwdriver. The six-dimensional sensor is connected to the flathead screwdriver. The computer is connected to the robotic arm via a connecting cable. The potentiometer bracket is provided with a potentiometer panel, and the potentiometer panel is provided with a potentiometer.

[0017] As a further improvement of the present invention, in step S1, the size of the adjustment hole on the potentiometer is 1mm×3mm, and the front end size of the flathead screwdriver is 0.7mm×2.4mm.

[0018] As a further improvement of the present invention, the stopping threshold F in step S2 Zthreshold It is 12N.

[0019] As a further improvement of the present invention, the initial rectangle of the rectangular trajectory in step S3 has a size of 0.15mm × 0.3mm, an X-axis increment Δx of 0.15mm, and a Y-axis increment Δy of 0.3mm.

[0020] The beneficial effects of this invention are:

[0021] This invention provides a potentiometer adjustment hole finding method based on a force feedback rectangular search strategy. Compared with the prior art, without increasing hardware investment or significantly increasing system computation, the hole finding accuracy is increased from 80.8% to 98.3%, improving the working efficiency of the entire automatic debugging system. Furthermore, during the hole finding process, the contact force between the screwdriver and the potentiometer adjustment knob panel is always kept within the set safety threshold range, avoiding damage to the potentiometer. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0023] Figure 1 This is a schematic diagram of the vision system structure;

[0024] Figure 2 This is a schematic diagram of the error analysis for the manhole.

[0025] Figure 3 This is a schematic diagram of the force analysis during the hole-finding process;

[0026] Figure 4 A schematic diagram of the rectangular trajectory for hole finding;

[0027] Figure 5 This is a schematic diagram of the hole-finding process using a flathead screwdriver.

[0028] In the diagram: 1. Base; 2. Robotic arm; 3. Camera; 4. Light source; 5. Lens; 6. Six-dimensional sensor; 7. Flathead screwdriver; 8. Computer; 9. Connecting cable; 10. Potentiometer bracket; 11. Potentiometer panel; 12. Potentiometer. Detailed Implementation

[0029] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0030] A method for locating potentiometer adjustment holes based on a force feedback rectangular search strategy includes a vision system for hole location, such as... Figure 1 The diagram shows the structure of the vision system, which includes a base 1, a computer 8, a robotic arm 2 mounted on the base 1, and a potentiometer bracket 10. The end of the robotic arm 2 is equipped with a camera 3, a light source 4, a lens 5, a six-dimensional sensor 6, and a flathead screwdriver 7. The six-dimensional sensor 6 is connected to the flathead screwdriver 7. The computer 8 is connected to the robotic arm 2 via a connecting cable 9. The potentiometer bracket 10 is equipped with a potentiometer panel 11, and a potentiometer 12 is mounted on the potentiometer panel 11.

[0031] The specific steps are as follows:

[0032] S1. Manhole error analysis.

[0033] Modeling and analysis are performed based on the dimensions of the adjustment hole on potentiometer 12 and the front end dimensions of the flathead screwdriver 7 in the vision system. In this embodiment, the adjustment hole is 1mm × 3mm, and the front end dimensions of the flathead screwdriver 7 are 0.7mm × 2.4mm. After the flathead screwdriver 7 in the vision system reaches the target point for coarse positioning, three situations may occur: deviation on the X-axis, deviation on the Y-axis, and deviation on both the X-axis and Y-axis. For example... Figure 2 As shown, Figure 2 In diagram (a), the deviation occurs on the X-axis. Figure 2 (b) shows the case where a deviation occurs on the Y-axis. Figure 2 (c) shows a deviation on both the X and Y axes.

[0034] In all three scenarios described above, the flathead screwdriver 7 will come into contact with the edge of the adjustment hole on the potentiometer 12, causing a contact force to be generated in the Z-axis direction of the six-dimensional sensor 6 in the vision system, i.e., it will be subjected to a force F in the opposite direction. z In this state, if the flathead screwdriver 7 is inserted downwards, it will damage the potentiometer 12.

[0035] S2, Force Analysis.

[0036] To achieve precise positioning based on force feedback, a force model is established and force analysis is performed, such as... Figure 3 As shown, when the tip of the flathead screwdriver 7 does not contact the surface of the potentiometer 12, the Z-axis direction of the six-dimensional sensor 6 on the vision system is not subjected to force. z The value is zero when the flathead screwdriver 7 comes into contact with the surface of the potentiometer 12. z It generates and rapidly increases in a vertically upward direction; a stop threshold F is set based on the force analysis results. Zthreshold The stopping threshold F will be set.Zthreshold This serves as the trigger condition for stopping the downward movement of the flathead screwdriver 7. In this embodiment, the stopping threshold F Zthreshold It is 12N.

[0037] S3, Hole-finding strategy design.

[0038] Based on the characteristics of the adjustment hole on potentiometer 12, a rectangular trajectory search strategy is adopted, with the search direction from the inside out, such as... Figure 4 As shown, the initial rectangle has dimensions of 0.15mm × 0.3mm, the X-axis increment Δx is 0.15mm, the Y-axis increment Δy is 0.3mm, the dashed box represents the outline of the flathead screwdriver 7, the cross mark represents the current center of the flathead screwdriver 7, and the solid box represents the center position of the adjustment hole on the potentiometer 12.

[0039] S4. Specific hole finding process.

[0040] The computer 8 in the vision system controls the robotic arm 2 to move the flathead screwdriver 7 via the connecting cable 9. After the flathead screwdriver 7 contacts the edge of the adjustment hole on the potentiometer 12, it detects F. z Rapidly increase until the preset stopping threshold F is reached. Zthreshold The screwdriver immediately stops moving downwards to avoid excessive impact on the adjustment hole on potentiometer 12. The state at this point is as follows: Figure 5 As shown in (a); maintain the contact state of the flathead screwdriver 7 and perform hole finding according to the rectangular trajectory search strategy. The state at this time is as follows. Figure 5 As shown in (b) and (c); when F is detected z When the value is zero, it indicates that the flathead screwdriver 7 is no longer in contact with the edge of the adjustment hole on the potentiometer 12. At this time, the flathead screwdriver 7 is inside the adjustment hole on the potentiometer 12, which means that the hole finding was successful. The flathead screwdriver 7 stops its hole finding movement, and the state at this time is as follows. Figure 5 As shown in (d).

[0041] Furthermore, to verify the accuracy of the invention during actual debugging, five images of the electro-optic potentiometer panels were taken under the same experimental conditions. Twenty-four electro-optic potentiometers at the same location in each image were randomly selected as target detection objects, and tests were conducted on the selected target electro-optic potentiometers. The success rates of the two algorithms were calculated, and the success rates of the rectangular hole-finding algorithm and the single-vision algorithm were compared using 120 sets of data. The data is shown in Table 1 below.

[0042] Table 1

[0043] Single vision algorithm Rectangular Hole Finding Algorithm Number of experiments 120 120 Number of successful insertions 97 118 Success rate 80.8％ 98.3％

[0044] Based on the previous data results, it can be seen that, compared with the prior art, the present invention improves the hole finding accuracy from 80.8% to 98.3% without increasing the investment in hardware equipment or significantly increasing the system's computing power, thereby improving the working efficiency of the entire automatic debugging system. Furthermore, during the hole finding process, the contact force between the screwdriver and the potentiometer adjustment knob panel is always kept within the set safety threshold range, thus avoiding damage to the potentiometer.

[0045] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely prisms of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A potentiometer adjustment hole locating method based on a force feedback rectangular search strategy, characterized in that: This includes a vision system for hole finding, with the following specific steps: S1. Manhole Error Analysis: Based on the size of the adjustment hole on the potentiometer (12) and the front end size of the flathead screwdriver (7) in the vision system, a modeling analysis is performed: After the flathead screwdriver (7) in the vision system reaches the target point for coarse positioning, three situations will occur: deviation on the X-axis, deviation on the Y-axis, and deviation on both the X-axis and Y-axis. This will cause the flathead screwdriver (7) to contact the edge of the adjustment hole on the potentiometer (12), and the six-dimensional sensor (6) in the vision system will generate a contact force in the Z-axis direction, that is, it will be subjected to a force F in the opposite direction. z ; S2, Force Analysis: Establish a force model and perform force analysis: When the end of the flathead screwdriver (7) does not contact the surface of the potentiometer (12), the six-dimensional sensor (6) on the vision system is not subjected to force in the Z-axis direction, F z The value is zero when the flathead screwdriver (7) comes into contact with the surface of the potentiometer (12). z It generates and rapidly increases in a vertically upward direction. If a flathead screwdriver (7) is inserted downward in this state, it will damage the potentiometer (12). Based on the force analysis results, a stop threshold F is set. Zthreshold The stopping threshold F will be set. Zthreshold As a trigger condition for stopping the downward movement of the flathead screwdriver (7); S3. Hole-finding strategy design: Based on the characteristics of the adjustment hole on the potentiometer (12), a rectangular trajectory search strategy is adopted, with the search direction from the inside to the outside; S4. Specific hole-finding process: The computer (8) in the vision system controls the robotic arm (2) to move the flathead screwdriver (7) via the connecting cable (9). After the flathead screwdriver (7) contacts the edge of the adjustment hole on the potentiometer (12), it detects F. z Rapidly increase until the preset stopping threshold F is reached. Zthreshold The screwdriver immediately stops moving downwards, maintaining the contact state of the flathead screwdriver (7) and searching for the hole according to the rectangular trajectory search strategy. When F is detected... z When the value is zero, it means that the flathead screwdriver (7) is no longer in contact with the edge of the adjustment hole on the potentiometer (12). At this time, the flathead screwdriver (7) is inside the adjustment hole on the potentiometer (12), which means that the hole finding is successful, and the flathead screwdriver (7) stops the hole finding movement.

2. The potentiometer adjustment hole finding method based on a force feedback rectangular search strategy according to claim 1, characterized in that: The vision system includes a base (1), a computer (8), a robotic arm (2) mounted on the base (1), and a potentiometer bracket (10). The end of the robotic arm (2) is equipped with a camera (3), a light source (4), a lens (5), a six-dimensional sensor (6), and a flathead screwdriver (7). The six-dimensional sensor (6) is connected to the flathead screwdriver (7). The computer (8) is connected to the robotic arm (2) via a connecting cable (9). The potentiometer bracket (10) is equipped with a potentiometer panel (11), and the potentiometer panel (11) is equipped with a potentiometer (12).

3. The potentiometer adjustment hole finding method based on a force feedback rectangular search strategy according to claim 1, characterized in that: In step S1, the size of the adjustment hole on the potentiometer (12) is 1mm×3mm, and the front end size of the flathead screwdriver (7) is 0.7mm×2.4mm.

4. The potentiometer adjustment hole finding method based on a force feedback rectangular search strategy according to claim 1, characterized in that: Stop threshold F in step S2 Zthreshold It is 12N.

5. The potentiometer adjustment hole finding method based on a force feedback rectangular search strategy according to claim 1, characterized in that: In step S3, the initial rectangle of the rectangular trajectory has a size of 0.15mm × 0.3mm, an X-axis increment Δx of 0.15mm, and a Y-axis increment Δy of 0.3mm.

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