Potentiometer adjustment hole searching method based on force feedback rectangular search strategy

Abstract

The invention relates to the technical field of aviation airborne equipment debugging and testing, in particular to a potentiometer adjusting hole searching method based on a force feedback rectangular search strategy, which comprises the following steps of: S1, analyzing a hole entering error; s2, carrying out stress analysis; s3, designing a hole searching strategy; and S4, a specific hole searching process. Compared with the prior art, the force feedback rectangular search strategy-based potentiometer adjusting hole searching method provided by the invention has the advantages that the hole searching accuracy is improved from 80.8% to 98.3% under the conditions of not increasing hardware equipment investment and not greatly increasing system operation amount, the working efficiency of a whole automatic debugging system is improved, and the cost is reduced. And in the hole searching process, the contact force of the screwdriver and the potentiometer for adjusting the knob panel is always kept within a set safety threshold range, so that the potentiometer is prevented from being damaged.

Description

Technical Field

[0001] The invention relates to the technical field of debugging and testing of aviation airborne equipment, and in particular to a method for finding a hole for a potentiometer adjustment hole based on a force feedback rectangular search strategy. Background Art

[0002] Fly-by-wire control is one of the iconic indicators of the third-generation aircraft. Its core computing component, the fly-by-wire computer, is responsible for the calculation and transformation of the aircraft control laws. The analog fly-by-wire computer uses an adjustable potentiometer to adjust and compensate for the control laws. During the aircraft overhaul, the potentiometer needs to be adjusted to adjust and test the performance parameters of the fly-by-wire control system. Since the onboard space displays the fly-by-wire computer potentiometer and its adjustment hole are small in size, manual adjustments were mostly used in the early stages, which was inefficient and had poor consistency.

[0003] Chinese patent CN202210319684.6 (published on March 15, 2024) discloses a method for automatic debugging of a fly-by-wire computer potentiometer, in which the position coordinates of the potentiometer adjustment hole in the visual coordinate system are realized by collecting potentiometer images and image processing through a visual system, and then the positioning of the potentiometer adjustment hole is realized through the conversion of the visual coordinate system and the robotic arm coordinate system. However, due to the mechanical errors and visual algorithm errors in the system itself, the equipment shaft hole matching accuracy is low, and the success rate of hole finding in this method is not high.

[0004] Chinese patent CN201810904192.7 (published on January 12, 2021) discloses a positioning method based on a four-eye visual positioning system, wherein the four-eye visual positioning system includes four CCD cameras arranged in parallel, two by two forming six groups of binocular visual positioning systems, and multiple groups of binocular visual positioning systems are used to obtain multiple groups of spatial coordinate data of the measured points, and the best spatial coordinate data of the measured points are obtained from these multiple groups of spatial data, thereby improving the positioning accuracy of the measured points. This method increases the amount of hardware, and obtaining multiple groups of images for processing increases the system data processing burden. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes a hole finding method for adjusting a potentiometer hole based on a force feedback rectangular search strategy.

[0006] The technical problem to be solved by the present invention is achieved by adopting the following technical solutions:

[0007] A method for finding a hole by adjusting a potentiometer based on a force feedback rectangular search strategy includes a visual system, and the visual system is used to find a hole. The specific steps are as follows:

[0008] S1. Analysis of hole entry error:

[0009] Modeling and analysis are performed based on the size of the adjustment hole on the potentiometer and the size of the front end of the flat-blade screwdriver in the visual system: After the flat-blade screwdriver in the visual system reaches the target point of coarse positioning, there will be three situations: deviation on the X-axis, deviation on the Y-axis, and deviation on both the X-axis and the Y-axis. This will cause the flat-blade screwdriver to contact the edge of the adjustment hole on the potentiometer, and the six-dimensional sensor on the visual 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 ;

[0010] S2. Force analysis:

[0011] Establish a force model and perform force analysis: When the end of the flat-blade screwdriver does not touch the surface of the potentiometer, the six-dimensional sensor on the vision system is not subjected to force in the Z-axis direction. z When the flat-blade screwdriver comes into contact with the surface of the potentiometer, F z The force is generated and increases rapidly in the vertically upward direction. In this state, if a flat-blade screwdriver is inserted downward, the potentiometer will be damaged. The stop threshold F is set according to the force analysis results. Zthreshold , the stopping threshold F Zthreshold As a trigger condition for stopping the downward movement of a slotted screwdriver;

[0012] S3. Hole-finding strategy design:

[0013] According to the characteristics of the adjustment hole on the potentiometer, a rectangular trajectory search strategy is adopted, and the search direction is from inside to outside;

[0014] S4. Specific hole-finding process:

[0015] The computer in the visual system controls the robot arm through the connecting wire to drive the flat-blade screwdriver to move. After the flat-blade screwdriver touches the edge of the adjustment hole on the potentiometer, F is detected. z Rapidly increases and reaches the preset stop threshold F Zthreshold The screwdriver immediately stops moving downward, keeps the contact state of the slotted screwdriver, and searches for holes according to the search strategy of the rectangular trajectory. z When it reaches zero, it indicates that the slotted screwdriver is no longer in contact with the edge of the adjustment hole on the potentiometer. At this time, the slotted screwdriver is in the adjustment hole on the potentiometer, indicating that the hole is found successfully, and the slotted screwdriver stops the hole-finding movement.

[0016] As a further improvement of the present invention, the visual system includes a base, a computer, a robotic arm arranged on the base, and a potentiometer bracket, a camera, a light source, a lens, a six-dimensional sensor and a flat-blade screwdriver are arranged at the end of the robotic arm, the six-dimensional sensor is connected to the flat-blade screwdriver, the computer is connected to the robotic arm via a connecting line, a potentiometer panel is arranged on the potentiometer bracket, and a potentiometer is arranged on the potentiometer panel.

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

[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 size of the initial rectangle of the rectangular track in step S3 is 0.15 mm×0.3 mm, the X-axis increment Δx is 0.15 mm, and the Y-axis increment Δy is 0.3 mm.

[0020] The beneficial effects of the present invention are:

[0021] The present invention provides a method for finding a hole for a potentiometer adjustment hole based on a force feedback rectangular search strategy. Compared with the prior art, the hole finding accuracy is increased from 80.8% to 98.3% without increasing the investment in hardware equipment and significantly increasing the amount of system calculations, thereby improving the working efficiency of the entire automatic debugging system. In addition, 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, thereby avoiding damage to the potentiometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0023] Figure 1 It is a schematic diagram of the visual system structure;

[0024] Figure 2 This is a schematic diagram of hole entry error analysis;

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

[0026] Figure 4 It is a schematic diagram of the hole-finding rectangular trajectory;

[0027] Figure 5 This is a schematic diagram of the hole-finding trajectory of a slotted screwdriver during the hole-finding process.

[0028] In the figure: 1. Base; 2. Robotic arm; 3. Camera; 4. Light source; 5. Lens; 6. Six-dimensional sensor; 7. Flat-blade screwdriver; 8. Computer; 9. Connecting wire; 10. Potentiometer bracket; 11. Potentiometer panel; 12. Potentiometer. DETAILED DESCRIPTION

[0029] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below with reference to the accompanying drawings and embodiments.

[0030] A method for finding a hole by adjusting a potentiometer based on a force feedback rectangular search strategy includes a visual system, and the visual system is used to find a hole, such as Figure 1 The figure shows a schematic diagram of the structure of the visual system, which includes a base 1, a computer 8, a robotic arm 2 arranged on the base 1, and a potentiometer bracket 10. A camera 3, a light source 4, a lens 5, a six-dimensional sensor 6 and a flat-blade screwdriver 7 are arranged at the end of the robotic arm 2. The six-dimensional sensor 6 is connected to the flat-blade screwdriver 7. The computer 8 is connected to the robotic arm 2 through a connecting line 9. A potentiometer panel 11 is arranged on the potentiometer bracket 10, and a potentiometer 12 is arranged on the potentiometer panel 11.

[0031] The specific steps are as follows:

[0032] S1. Analysis of hole entry error.

[0033] Modeling and analysis are performed based on the size of the adjustment hole on the potentiometer 12 and the size of the front end of the flat-blade screwdriver 7 in the visual system. In this embodiment, the size of the adjustment hole is 1mm×3mm, and the size of the front end of the flat-blade screwdriver 7 is 0.7mm×2.4mm. After the flat-blade screwdriver 7 in the visual system reaches the target point of rough positioning, there will be three situations: deviation on the X axis, deviation on the Y axis, and deviation on both the X axis and the Y axis. Figure 2 As shown, Figure 2 (a) is the case where a deviation occurs on the X-axis. Figure 2 (b) shows the case where there is a deviation on the Y axis. Figure 2 (c) is a case where deviation occurs on both the X-axis and the Y-axis.

[0034] The above three situations will cause the flat-blade screwdriver 7 to contact the edge of the adjustment hole on the potentiometer 12, and the six-dimensional sensor 6 on the visual 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 In this state, if the slotted screwdriver 7 is inserted downward, the potentiometer 12 will be damaged.

[0035] S2. Force analysis.

[0036] In order 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 flat-blade screwdriver 7 does not touch the surface of the potentiometer 12, the six-dimensional sensor 6 on the visual system is not subjected to force in the Z-axis direction, F z is zero, when the slotted screwdriver 7 comes into contact with the surface of the potentiometer 12, F z The force is generated and increases rapidly in the vertical direction. The stop threshold F is set according to the force analysis results. Zthreshold , the stopping threshold FZthreshold As a trigger condition for the flat-blade screwdriver 7 to stop moving downward. In this embodiment, the stop threshold F Zthreshold It is 12N.

[0037] S3. Hole-finding strategy design.

[0038] According to the characteristics of the adjustment hole on the potentiometer 12, a rectangular track search strategy is adopted, and the search direction is from inside to outside, such as Figure 4 As shown, the size of the initial rectangle is 0.15mm×0.3mm, the X-axis increment Δx is 0.15mm, the Y-axis increment Δy is 0.3mm, the dotted box represents the outline of the flat-blade screwdriver 7, the cross mark represents the current center of the flat-blade 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 visual system controls the robot arm 2 to drive the flat-blade screwdriver 7 to move through the connecting line 9. After the flat-blade screwdriver 7 contacts the edge of the adjustment hole on the potentiometer 12, the F z Rapidly increases and reaches the preset stop threshold F Zthreshold , the screwdriver immediately stops moving downward to avoid excessive impact on the adjustment hole on the potentiometer 12. Figure 5 As shown in (a); keep the contact state of the slotted screwdriver 7 and search for holes according to the search strategy of the rectangular trajectory. At this time, the state is as follows Figure 5 As shown in (b) and (c); when F is detected z After it reaches zero, it means that the slotted screwdriver 7 is no longer in contact with the edge of the adjustment hole on the potentiometer 12. At this time, the slotted screwdriver 7 is in the adjustment hole on the potentiometer 12, indicating that the hole is found successfully. The slotted screwdriver 7 stops the hole-finding movement. At this time, the state is as follows Figure 5 As shown in (d).

[0041] Furthermore, in order to verify the accuracy of the present invention in the actual debugging process, under the same experimental conditions, five images of the panel of the teletype potentiometer were taken, and 24 teletype potentiometers at the same position in each photo were randomly selected as the target detection objects, and the selected target teletype potentiometers were tested. Finally, the success rates of the two algorithms were calculated, and the rectangular hole-finding algorithm and the single vision algorithm were compared in success rate with 120 sets of data. The data are 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] It can be seen from the last data results that compared with the prior art, the present invention improves the hole-finding accuracy from 80.8% to 98.3% without increasing the hardware equipment investment and significantly increasing the system computing power, thereby improving the working efficiency of the entire automatic debugging system. In 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, thereby avoiding damage to the potentiometer.

[0045] The above shows and describes 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 above embodiments and descriptions only describe the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for finding a hole by adjusting a potentiometer based on a force feedback rectangular search strategy, characterized in that: A visual system is included, and the visual system is used to find the hole. The specific steps are as follows: S1. Analysis of hole entry error: Modeling and analysis are performed based on the size of the adjustment hole on the potentiometer (12) and the front end size of the flat-blade screwdriver (7) in the visual system: after the flat-blade screwdriver (7) in the visual system reaches the target point of rough positioning, three situations may occur: deviation on the X axis, deviation on the Y axis, and deviation on both the X axis and the Y axis. This will cause the flat-blade screwdriver (7) to contact the edge of the adjustment hole on the potentiometer (12), and a contact force will be generated in the Z axis direction of the six-dimensional sensor (6) on the visual system, 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 tip of the flat-blade screwdriver (7) does not touch the surface of the potentiometer (12), the six-dimensional sensor (6) on the visual system is not subjected to force in the Z-axis direction, F z When the slotted screwdriver (7) comes into contact with the surface of the potentiometer (12), F z The force is generated and increases rapidly in a vertically upward direction. In this state, if a slotted screwdriver (7) is inserted downward, the potentiometer (12) will be damaged. The stop threshold F is set according to the force analysis result. Zthreshold , the stopping threshold F Zthreshold As a trigger condition for stopping the downward movement of the slotted screwdriver (7); S3. Hole-finding strategy design: According to the characteristics of the adjustment hole on the potentiometer (12), a rectangular track search strategy is adopted, and the search direction is from inside to outside; S4. Specific hole-finding process: The computer (8) in the visual system controls the robot arm (2) through the connecting line (9) to drive the flat-blade screwdriver (7) to move. After the flat-blade screwdriver (7) contacts the edge of the adjustment hole on the potentiometer (12), F is detected. z Rapidly increases and reaches the preset stop threshold F Zthreshold , the screwdriver immediately stops moving downward, maintains the contact state of the slotted screwdriver (7) and searches for holes according to the search strategy of the rectangular trajectory. When F is detected z When it reaches zero, it means that the slotted screwdriver (7) is no longer in contact with the edge of the adjustment hole on the potentiometer (12). At this time, the slotted screwdriver (7) is in the adjustment hole on the potentiometer (12), indicating that the hole is found successfully, and the slotted screwdriver (7) stops the hole-finding movement.

2. The method for finding a hole by adjusting a potentiometer based on a force feedback rectangular search strategy according to claim 1, characterized in that: The visual system comprises a base (1), a computer (8), a mechanical arm (2) arranged on the base (1), and a potentiometer bracket (10); a camera (3), a light source (4), a lens (5), a six-dimensional sensor (6), and a flat-blade screwdriver (7) are arranged at the end of the mechanical arm (2); the six-dimensional sensor (6) is connected to the flat-blade screwdriver (7); the computer (8) is connected to the mechanical arm (2) via a connecting line (9); a potentiometer panel (11) is arranged on the potentiometer bracket (10), and a potentiometer (12) is arranged on the potentiometer panel (11).

3. The method for finding a hole by adjusting a potentiometer 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 1 mm×3 mm, and the size of the front end of the flat-blade screwdriver (7) is 0.7 mm×2.4 mm.

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

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

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