A multi-level adaptive conformal compaction method

Abstract

The present invention belongs to the field of robotic automated drilling and riveting, and discloses a multi-level adaptive conformal pressing method. The method can realize a small force push of the pressure foot through a driving and feedback module, ensuring that the conformal module can effectively contact the processed curved surface part; realize adaptive conformal of different points of the curved surface part through the conformal module; realize shape locking through the locking module; accurately apply the required pressing force through the driving and feedback module, thus completing the first-level conformal pressing; the detection unit detects the contact state of the conformal contact point and determines whether multi-level conformal pressing is required; if necessary, the locking module and the driving and feedback module act synchronously to realize deformation compensation during the first-level conformal pressing, complete the second to multiple levels of conformal pressing, and ensure the accuracy of conformal pressing and the stability of pressing. The method of the present invention can realize conformal pressing for different curved surface parts, effectively reduce the deformation of the workpiece, and compensate for the deformation of the workpiece caused by pressing through multi-level adaptive conformal pressing.

Description

Technical Field

[0001] The present invention belongs to the field of robot automated drilling and riveting, and in particular relates to a multi-stage adaptive conformal pressing method which can conformally press and reduce deformation according to the surface shape of a workpiece. Background Art

[0002] As the precision requirements for drilling components in the aerospace, energy and power, and marine sectors increase, traditional manual drilling, due to its low efficiency and poor precision, has gradually become unable to meet these demands. With the rise of automation in the fields of digital systems and industrial robots, high-degree-of-freedom automated drilling technology, using industrial robots with end effectors, has rapidly developed. As a key component of robotic automated drilling systems, the pressure foot serves to clamp the workpiece, increase drilling system rigidity, eliminate gaps between layers, and perform normal detection, making it a key research area in automated drilling technology.

[0003] While some research has been conducted domestically and internationally on the pressure foot devices of robotic automated drilling systems, less research has been conducted on workpiece clamping methods. In his paper "Design of a Holemaking End Effector Unit," Li Shujun proposed a double-sided cylinder-driven method for clamping the workpiece and calibrated the clamping force. The RDS210 robotic automated drilling system developed by Toptronics features a highly integrated pressure foot unit, integrating normal measurement with the pressure foot and employing a flexible rubber pressure head to increase frictional resistance on the cutting surface after clamping. In the paper "ONe-sided Cell End Effector Robotic Drilling System," the end effector of the ONCE robotic automated drilling system, jointly developed by Electroimpact and Airbus, incorporates a clamping unit at its front end, using the pressure foot to apply pressure to the workpiece to prevent vibration during machining. The aforementioned pressure foot devices all feature rigid, planar structures. This clamping method is particularly suitable for flat or slightly curved workpieces. However, for workpieces with large curvatures, especially thin-walled ones, the pressure foot can significantly deform the workpiece, resulting in poor hole diameter accuracy and difficulty meeting drilling requirements. The challenge of adaptively conforming the workpiece to its surface features, increasing the actual contact area and minimizing workpiece deformation while ensuring stable clamping and improving drilling quality remains a pressing issue. Summary of the Invention

[0004] In order to overcome the problems existing in the above-mentioned prior art, the present invention proposes a multi-level adaptive conformal pressing method, which is implemented based on a drive and feedback module, a conformal module and a locking module. The drive and feedback module can realize the small force push of the pressure foot to ensure that the conformal module can effectively contact the processed curved surface part; the conformal module realizes adaptive conformalization of different points of the curved surface part; the locking module realizes fixed locking; the drive and feedback module accurately applies the required pressing force, thus completing the first-level conformal pressing; the detection unit detects the contact state of the conformal contact point to determine whether multi-level conformalization is required; if necessary, the locking module and the drive and feedback module act synchronously to realize deformation compensation during the first-level conformal pressing, complete the second to multiple levels of conformal pressing, and ensure the accuracy of conformal pressing and the stability of pressing. The method of the present invention can realize conformal pressing for different curved surface parts, effectively reduce the deformation of the workpiece, and compensate for the deformation of the workpiece caused by pressing through multi-level adaptive conformal pressing, improve the accuracy and stability of conformal pressing, and further improve the processing accuracy. The adaptive conformal method can realize automated, low-cost, high-precision and efficient processing.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution of the present invention is:

[0006] A multi-stage adaptive conformal pressing method is implemented based on a driving and feedback module 1, a conformal module 2, a locking module 3 and a base module 4.

[0007] The driving and feedback module 1 is used to realize the low-force push of the pressure foot to ensure that the conformal module can effectively contact the processed curved surface part, including a cylinder 101, a connecting plate 102, a driving connector 103, an air pipe 104, a speed regulating valve 105, a solenoid valve 106, an electric proportional valve 107, a triplet 108, an air source 109, a pressure sensor 110, and an amplifier 111; the air pipe 104 is used to realize the connection of the various parts of the air path and to transmit the air pressure. The air source 109 is connected to the laboratory air source pipeline to provide a thrust source for the pressure foot. One end of the triplet 108 is connected to the air source 109 and the other end is connected to the electric proportional valve 107 to filter impurities, oil mist, and dryness in the gas. The other end of the electric proportional valve 107 is connected to the solenoid valve 106. The electric proportional valve 107 is also connected to the control system to achieve the output of different pressing forces by receiving the current signal of the control system. The air inlet of the solenoid valve 106 is connected to the electric proportional valve 10 7 is connected, and the air outlet is connected to the rod end and the rodless end of the cylinder 101 respectively through two speed regulating valves 105. The solenoid valve 106 is used to realize the extension and retraction of the pressure foot. The speed regulating valve 105 controls the extension speed of the cylinder 101 by adjusting the opening, so that the compacting process is more stable. The cylinder 101 is used as the terminal actuator driven by the air circuit to complete the thrust output of the pressure foot. The cylinder 101 is fixed to the frame unit of the robot automatic hole making end actuator through the connecting plate 102, and ensures that the axis of the compacting cylinder 101 coincides with the central axis of the frame unit; one end of the pressure sensor 110 is coaxially connected to the piston rod of the cylinder 101; the other end is fixed to the driving connector 103; the lower surface of the driving connector 103 is connected to the base module 4, which plays the role of transmitting the cylinder thrust; one end of the amplifier 111 is connected to the pressure sensor 110 to receive and amplify the pressure signal, and the other end is connected to the control system, and finally the compacting force is transmitted to the control system. The control system is also connected to the driving unit 301 of the locking module 3 to control the degree of locking of the cylindrical pin array 201 in the conformal module 2 by the driving unit 301 .

[0008] The conformal module 2, used to achieve adaptive conformity at different points on a curved surface, includes a cylindrical pin 201, a return spring 202, and a baffle. The cylindrical pin 201 is divided into three sections, A, B, and C, from its tail end to its head end. Section C has the largest axial diameter (Rc), section B has the smallest axial diameter (Rb), and section A has an axial diameter (Ra) between sections C and B. The baffle is fixed on the base module 4, and an array of through holes is provided on the baffle, and the through holes are clearance-matched with the cylindrical pin 201; the return spring 202 and the baffle are slidably sleeved on the B section of the cylindrical pin 201 in sequence, and the two end faces of the baffle are respectively in contact with the A section end face of the cylindrical pin 201 and one end of the return spring 202, and the other end of the return spring 202 is in contact with the C section end face of the cylindrical pin 201; the cylindrical pins 201 on the same baffle together constitute a cylindrical pin 201 array, and the cylindrical pin 201 array is tangent to the inner wall surface of the assembly space reserved on the base module 4 at the C section, and the assembly space reserved on the base module 4 provides a guide for the extension and retraction of the cylindrical pin 201.

[0009] The locking module 3 is used to lock the conformable module 2 in a fixed shape, and includes a drive unit 301, a lever 302, a lever pin 303, and a pressure block 305. The drive unit 301 is fixed to the base module 4, and the pressure block 305 is arranged in the base module 4, capable of contacting one side of the cylindrical pin array 201 and providing a certain compression space. One end of the lever 302 is connected to the drive unit 301, and the other end is rotatably connected to the base module 4 via the lever pin 303. One end of the lever 302 is driven by the drive unit 301, and the other end can rotate around the lever pin 303 relative to the base module 4, thereby compressing the pressure block 305.

[0010] The specific steps of the multi-level adaptive conformal compaction method are as follows:

[0011] S1: Turn on the air source 109, set the thrust through the control system, and control the opening of the electric proportional valve 107 to control the thrust output of the cylinder 101 and push out the conformable module 2;

[0012] S2: The cylindrical pin array 201 in the conformal module 2 contacts the workpiece to be machined. According to the curvature characteristics of the workpiece surface, the cylindrical pin array 201 realizes adaptive conformal at different points.

[0013] S3: The control system controls all the driving units 301 in the locking module 3 to act simultaneously, pushing the lever 302 to lock the cylindrical pin 201 after the shape is formed, and completing the shape locking;

[0014] S4: The control system sets the clamping force and the opening of the electric proportional valve 107 to control the output thrust of the cylinder 101. The pressure sensor 110 measures the clamping force in real time and feeds it back to the control system. The control system then performs PID control to precisely apply the clamping force to the workpiece.

[0015] S5: The workpiece is deformed under pressure, the curvature changes, and some contacts in the cylindrical pin 201 array are separated from the workpiece surface;

[0016] S6: Determine whether the requirement that all contact points are in contact with the workpiece surface is met;

[0017] S7: If the conditions are not met, the control system controls the driving units 301 of the locking module 3 to act simultaneously, pushing the lever 302 to slightly unlock the cylindrical pin 201;

[0018] S8: The contact point separated from the workpiece surface automatically rebounds under the action of the return spring 202 and comes into contact with the workpiece surface again;

[0019] S9: Repeat step S3 to complete the second locking;

[0020] S10: Repeat S6 to S9 until the requirements are met; the robot's automatic hole-making end effector starts hole-making.

[0021] Furthermore, the amplifier amplifies the signal measured by the pressure sensor into a 4-20mA current signal and feeds it back to the control system.

[0022] Furthermore, the effective stroke of the cylindrical pin is 24.5 mm.

[0023] Furthermore, the baffle includes a pin connecting plate 203 and a pin fixing plate 204. The pin connecting plate 203 has an array of perfectly circular through-holes, and the pin fixing plate 204 has a gourd-shaped irregular hole. The large circular hole diameter of the irregular hole is equal to the diameter of the perfectly circular through-hole on the pin connecting plate 203, and is larger than the axial diameter Ra of the cylindrical pin 201A section and smaller than the axial diameter Rc of the cylindrical pin 201C section. The small circular hole diameter of the irregular hole is larger than the axial diameter Rb of the cylindrical pin 201B section and smaller than the axial diameter Ra of the cylindrical pin 201A section. The pin connecting plate 203 and the pin fixing plate 204 have equal plate dimensions. When the two are completely overlapped, the minimum diameter of the through-holes exhibits a clearance fit with the cylindrical pin 201B section. When the pin connecting plate 203 and the pin fixing plate 204 are overlapped and fixed to each other, the cylindrical pin 201 can be positioned.

[0024] Furthermore, the pin connecting plate 203 and the pin fixing plate 204 are completely overlapped and connected by screws, and the two are placed together in the reserved space between the pin base 105 and the pin fixing block 104 to achieve clamping and fixing.

[0025] Furthermore, the locking module 3 also includes a locking block 304 and a drive unit connecting plate 306, and the lever pin 303 passes through the lever 302 and the locking block 304 respectively, and is clearance-matched with the lever 302 and the locking block 304 to provide a fulcrum for the rotation of the lever 302; the locking block 304 is fixedly connected to the base module 4; the drive unit 301 is fixed on the drive unit connecting plate 306, and then the assembly of the drive unit 301 and the drive unit connecting plate 306 is positioned on the base module 4 through three-sided positioning.

[0026] Furthermore, the locking block 304 is fixedly connected to the pin fixing block 404. The driving unit 301 and the driving unit connecting plate 306 are fixed on the driving unit rear cover 403 and locked by screws.

[0027] The beneficial effects of the present invention are as follows: the present invention can realize precise control of the clamping force through the driving and feedback modules; the conformal clamping of workpieces with different curvatures can be realized through the conformal module, thereby reducing the deformation of the workpiece; the consistency of the contact surface of the cylindrical pin after conforming and the surface shape of the workpiece can be achieved through the locking module, thereby improving the conformal accuracy; the deformation of the workpiece caused by clamping can be compensated through multi-level conformal locking, thereby improving the accuracy and stability of conforming and further improving the processing accuracy; the pressure foot driving and feedback modules, conformal modules and locking modules are highly integrated, and the overall structure is compact, which improves the accessibility and universality of the pressure foot and expands its working range, ultimately realizing efficient and high-precision hole processing of workpieces with curvature in the fields of aerospace, energy and power, marine engineering, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flow chart of a multi-stage adaptive conformal compaction method applicable to curved surface structural parts of the present invention;

[0029] Figure 2 is an embodiment of the method of the present invention;

[0030] Figure 3 Schematic diagram of the drive and feedback module of the method of the present invention;

[0031] Figure 4 Schematic diagram of the gas circuit system of the drive and feedback module of the method of the present invention;

[0032] Figure 5 Schematic diagram of the main body of the form-fitting module of the method of the present invention;

[0033] Figure 6 This is a partial cross-sectional view of the conformable module of the present invention;

[0034] Figure 7 This is a schematic diagram of the installation of the locking unit of the present invention;.

[0035] In the figure: 1- drive and feedback module; 2- conformal module; 3- locking module; 4- base module; 101- cylinder; 102- connecting plate; 103- driving connector; 104- air pipe; 105- speed control valve; 106- solenoid valve; 107- electrical proportional valve; 108- triplex; 109- air source; 110- pressure sensor; 111- amplifier; 301- cylindrical pin; 302- return spring; 303- pin detection unit; 401- locking cylinder; 402- lever group. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer and enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the technical solutions claimed to be protected by the present invention include but are not limited to the following embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative work should fall within the scope of protection of the present invention.

[0037] This embodiment discloses a multi-level adaptive conformal compaction method, referring to Figure 1 and Figure 2 The method is implemented based on a driving and feedback module 1, a conforming module 2, a locking module 3 and a base module 4.

[0038] The drive and feedback module 1 enables the pressure foot to be pushed out with minimal force, ensuring that the conforming module 2 can effectively contact the curved workpiece being machined. The conforming module 2 has a matrix-arranged cylindrical pin that can freely extend and retract to achieve adaptive conforming at different points on the curved workpiece, and a detection module can detect the contact state between the cylindrical pin and the workpiece. The locking module 3 simultaneously locks the cylindrical pin to ensure the accuracy and stability of conforming. The drive and feedback module 1 precisely applies the required pressing force, thus completing the first level of conforming compression. By detecting the contact state of the conforming contact point, it is determined whether multiple levels of conforming are required. If necessary, the locking module 3 and the drive and feedback module 1 operate synchronously to achieve deformation compensation during the first level of conforming compression, completing the second to multiple levels of conforming compression, ensuring the accuracy and stability of conforming. The method can adapt to curved workpieces with a certain curvature. By conforming and then pressing, the deformation of the workpiece can be reduced, effectively improving machining accuracy. The adaptive conforming method can achieve automated, low-cost, high-precision and efficient machining.

[0039] The conformal module 2 includes a cylindrical pin 201, a return spring 202, a pin connecting plate 203, and a pin fixing plate 204. The cylindrical pin 201 is divided into three sections, A, B, and C, from the tail end to the head end. Section C has the largest axial diameter Rc, section B has the smallest axial diameter Rb, and section A has an axial diameter Ra between sections C and B. The pin connecting plate 203 is provided with an array of perfectly circular through holes, and the pin fixing plate 204 is provided with gourd-shaped irregular holes. The large circular hole diameter of the irregular hole is equal to the diameter of the perfectly circular through hole on the pin connecting plate 203, and is larger than the axial diameter Ra of section A of the cylindrical pin 201 and smaller than the axial diameter Rc of section C of the cylindrical pin 201. The small circular hole diameter of the irregular hole is larger than the axial diameter Rb of section B of the cylindrical pin 201 and smaller than the axial diameter Ra of section A of the cylindrical pin 201. The pin connecting plate 203 and the pin fixing plate 204 have equal surface dimensions. When fully aligned, the minimum diameter of the through hole is aligned with the clearance of the cylindrical pin 201B segment. When the pin connecting plate 203 and the pin fixing plate 204 are aligned and fixed to each other via screws, the cylindrical pin 201 is positioned. The pin connecting plate 203 and the pin fixing plate 204 are placed together in the space reserved for the pin base 105 and the pin fixing block 104 for clamping and securing. The return spring 202, the pin connecting plate 203, and the pin fixing plate 204 are slidably mounted on the B section of the cylindrical pin 201 in sequence, the outer end face of the pin fixing plate 204 contacts the A section end face of the cylindrical pin 201, the inner end face of the pin connecting plate 203 contacts one end of the return spring 202, and the other end of the return spring 202 contacts the C section end face of the cylindrical pin 201; the cylindrical pins 201 on the same pin connecting plate 203 together constitute a cylindrical pin 201 array, and the cylindrical pin 201 array is tangent to the inner wall surface of the assembly space reserved on the pin fixing block 104 of the base module 4 at the C section, and the assembly space reserved by the pin fixing block 104 provides a guide for the extension and retraction of the cylindrical pin 201.

[0040] The locking module 3 includes a drive unit 301, a lever 302, a lever pin 303, a locking block 304, a pressure block 305, and a drive unit connecting plate 306. The pressure block 305 is set in the pin fixing block 104 of the base module 4, and can contact one side of the cylindrical pin array 201 with a certain compression space. When the cam 310 is in the closed position, the cam 310 will be in the closed position, so the cam 310 will be in the closed position when the cam 310 is in the open position, and the cam 310 will be in the open position when the cam 310 is in the closed position.

[0041] The driving and feedback module 1 is used to realize the low-force push of the pressure foot to ensure that the conformal module can effectively contact the processed curved surface part, including a cylinder 101, a connecting plate 102, a driving connector 103, an air pipe 104, a speed regulating valve 105, a solenoid valve 106, an electric proportional valve 107, a triplet 108, an air source 109, a pressure sensor 110, and an amplifier 111; the air pipe 104 is used to realize the connection of the various parts of the air path and to transmit the air pressure. The air source 109 is connected to the laboratory air source pipeline to provide a thrust source for the pressure foot. One end of the triplet 108 is connected to the air source 109 and the other end is connected to the electric proportional valve 107 to filter impurities, oil mist, and dryness in the gas. The other end of the electric proportional valve 107 is connected to the solenoid valve 106. The electric proportional valve 107 is also connected to the control system to achieve the output of different pressing forces by receiving the current signal of the control system. The air inlet of the solenoid valve 106 is connected to the electric proportional valve 10 7 is connected, and the air outlet is connected to the rod end and the rodless end of the cylinder 101 respectively through two speed regulating valves 105. The solenoid valve 106 is used to realize the extension and retraction of the pressure foot. The speed regulating valve 105 controls the extension speed of the cylinder 101 by adjusting the opening, so that the compacting process is more stable. The cylinder 101 is used as the terminal actuator driven by the air circuit to complete the thrust output of the pressure foot. The cylinder 101 is fixed to the frame unit of the robot automatic hole making end actuator through the connecting plate 102, and ensures that the axis of the compacting cylinder 101 coincides with the central axis of the frame unit; one end of the pressure sensor 110 is coaxially connected to the piston rod of the cylinder 101; the other end is fixed to the driving connector 103; the lower surface of the driving connector 103 is connected to the base module 4, which plays the role of transmitting the cylinder thrust; one end of the amplifier 111 is connected to the pressure sensor 110 to receive and amplify the pressure signal, and the other end is connected to the control system, and finally the compacting force is transmitted to the control system. The control system is also connected to the driving unit 301 of the locking module 3 to control the degree of locking of the cylindrical pin array 201 in the conformal module 2 by the driving unit 301 .

[0042] In order to achieve the above-mentioned purpose of the invention, the technical solution of the present invention is as follows:

[0043] S1: Turn on the air source 109, set the thrust through the control system, and control the opening of the electric proportional valve 107 to control the thrust output of the cylinder 101 and push out the conformable module 2;

[0044] S2: The cylindrical pin array 201 in the conformal module 2 contacts the workpiece to be machined. According to the curvature characteristics of the workpiece surface, the cylindrical pin array 201 realizes adaptive conformal at different points.

[0045] S3: The control system controls all the driving units 301 in the locking module 3 to act simultaneously, pushing the lever 302 to lock the cylindrical pin 201 after the shape is formed, and completing the shape locking;

[0046] S4: The control system sets the clamping force and the opening of the electrical proportional valve 107 to control the output thrust of the cylinder 101. The pressure sensor 110 measures the clamping force in real time and feeds it back to the control system. The control system performs PID control to accurately apply the clamping force to the workpiece.

[0047] S5: The workpiece is deformed under pressure, the curvature changes, and some contacts in the cylindrical pin 201 array are separated from the workpiece surface;

[0048] S6: Determine whether the requirement that all contact points are in contact with the workpiece surface is met;

[0049] S7: If the conditions are not met, the control system controls the driving units 301 of the locking module 3 to act simultaneously, pushing the lever 302 to slightly unlock the cylindrical pin 201;

[0050] S8: The contact point separated from the workpiece surface automatically rebounds under the action of the return spring 202 and comes into contact with the workpiece surface again;

[0051] S9: Repeat step S3 to complete the second locking;

[0052] S10: Repeat S6 to S9 until the requirements are met; the robot's automatic hole-making end effector starts hole-making.

[0053] Further, refer to Figure 1 and Figure 2 After the multi-level adaptive conformal pressing method is completed, the above steps are repeated to achieve continuous processing under multi-level adaptive conformal pressing.

[0054] Furthermore, the amplifier 111 amplifies the signal of the pressure sensor 110 into a 4-20 mA current signal, and feeds it back to the control system as an input for PID regulation of the control system.

[0055] Further, refer to Figure 5 The effective stroke of the cylindrical pin 301 is 24.5mm, which can adapt to workpieces with a certain curvature; the reset spring is compressed during the first-level conforming process, and the cylindrical pin contacts the workpiece surface and retracts; in multi-level conforming, some cylindrical pins that do not contact the workpiece surface rebound with the help of spring force, contact the workpiece surface twice or multiple times, compensate for the deformation of the workpiece caused by compression, and improve the accuracy and stability of conforming; by detecting the contact state between the contact and the workpiece, it is determined whether the contact is conformed; after the conforming is completed, the spring force of the reset spring will rebound the cylindrical pin to its original position.

[0056] Further, refer to Figure 5 There are four driving units 301 in the locking module 3, which need to output simultaneously during locking to ensure the simultaneity of locking and prevent the cylindrical pins in different areas from being interfered with by the locking of other parts; the lever group is driven by the locking cylinder, and the locking is achieved by applying radial compression force to the cylindrical pin group and generating a larger friction force. The maximum locking force can be increased or decreased by adjusting the position of the fulcrum.

[0057] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A multi-stage adaptive conformal compaction method, characterized in that: The method is implemented based on a driving and feedback module (1), a conforming module (2), a locking module (3) and a base module (4); The driving and feedback module (1) is used to realize the small force push of the pressure foot to ensure that the conforming module can effectively contact the processed curved surface part, including a cylinder (101), a connecting plate (102), a driving connecting part (103), an air pipe (104), a speed regulating valve (105), a solenoid valve (106), an electric proportional valve (107), a triplet (108), an air source (109), a pressure sensor (110), and an amplifier (111); the air pipe (104) is used to realize the connection of various parts of the air path and play the role of transmitting air pressure, and the air source (109) is connected to the laboratory The air source pipeline provides a thrust source for the pressure foot. One end of the triplex (108) is connected to the air source (109), and the other end is connected to the electric proportional valve (107), which plays a role in filtering impurities, oil mist, and drying in the gas. The other end of the electric proportional valve (107) is connected to the electromagnetic valve (106). The electric proportional valve (107) is also connected to the control system and realizes the output of different pressing forces by receiving the current signal of the control system. The air inlet of the electromagnetic valve (106) is connected to the electric proportional valve (107), and the air outlet is connected to the cylinder (109) through two speed regulating valves (105). 01) has a rod end and a rodless end, the solenoid valve (106) is used to realize the extension and retraction of the pressure foot, the speed regulating valve (105) controls the extension speed of the cylinder (101) by adjusting the opening, so that the pressing process tends to be more stable, the cylinder (101) is used as the terminal actuator driven by the air circuit to complete the thrust output of the pressure foot, the cylinder (101) is fixed on the frame unit of the robot automatic hole making end actuator through the connecting plate (102), and it is ensured that the axis of the pressing cylinder (101) coincides with the central axis of the frame unit; one end of the pressure sensor (110) is connected to the cylinder (101) The plug rod is coaxially connected; the other end is fixed on the driving connection member (103); the lower surface of the driving connection member (103) is connected to the base module (4), and plays a role in transmitting the cylinder thrust; one end of the amplifier (111) is connected to the pressure sensor (110), and plays a role in receiving and amplifying the pressure signal, and the other end is connected to the control system, and finally transmits the pressing force to the control system; the control system is also connected to the driving unit (301) of the locking module (3), and controls the degree of locking of the cylindrical pin array (201) in the conformal module (2) by the driving unit (301); The conforming module (2) is used to realize adaptive conforming of different points of the curved surface part, and comprises a cylindrical pin (201), a reset spring (202), and a baffle; the cylindrical pin (201) is divided into three sections A, B, and C from the tail end to the head end, the shaft diameter Rc of the C section is the largest, the shaft diameter Rb of the B section is the smallest, and the shaft diameter Ra of the A section is between the C section and the B section; the baffle is fixed on the base module (4), and an array of through holes is provided on the baffle, and the through holes are in clearance fit with the cylindrical pin (201); the reset spring (202) and the baffle are slidably sleeved on the cylindrical pin (201) in sequence. The B section of the pin (201) and the two end surfaces of the baffle are in contact with the A section end surface of the cylindrical pin (201) and one end of the return spring (202), respectively. The other end of the return spring (202) is in contact with the C section end surface of the cylindrical pin (201). The cylindrical pins (201) on the same baffle together form a cylindrical pin (201) array. The cylindrical pin (201) array is tangent to the inner wall surface of the assembly space reserved on the base module (4) at the C section. The assembly space reserved on the base module (4) provides a guide for the extension and contraction of the cylindrical pin (201). The locking module (3) is used for shaping and locking the conformable module (2), and comprises a driving unit (301), a lever (302), a lever pin (303), and a pressing block (305); the driving unit (301) is fixed on the base module (4), and the pressing block (305) is arranged in the base module (4), and can contact one side of the cylindrical pin (201) array and has a certain pressing space; one end of the lever (302) is connected to the driving unit (301), and the other end is rotatably connected to the base module (4) through the lever pin (303); one end of the lever (302) is driven by the driving unit (301), and the other end can perform a rotational motion around the lever pin (303) relative to the base module (4), thereby pressing the pressing block (305); The specific steps of the multi-level adaptive conformal compaction method are as follows: S1: Open the air source (109), set the thrust through the control system, and control the opening of the electric proportional valve (107) to control the thrust output of the cylinder (101) and push out the follower module (2); S2: The cylindrical pin array (201) in the conformal module (2) contacts the curved surface workpiece to be processed, and the cylindrical pin array (201) realizes adaptive conformal at different points according to the curvature characteristics of the workpiece surface; S3: All the driving units (301) in the locking module (3) are controlled by the control system to act simultaneously, pushing the lever (302) to achieve the locking of the cylindrical pin (201) after the shape is formed, thereby completing the shape-fixing locking; S4: The control system sets the clamping force and the opening of the electric proportional valve (107) to control the thrust output by the cylinder (101). The pressure sensor (110) measures the clamping force in real time and feeds it back to the control system. The control system performs PID control to accurately apply the clamping force to the workpiece. S5: The workpiece is deformed by pressure, the curvature changes, and some contacts in the cylindrical pin (201) array are separated from the workpiece surface; S6: Determine whether the requirement that all contact points are in contact with the workpiece surface is met; S7: If the conditions are not met, the control system controls the driving units (301) of the locking module (3) to act simultaneously, pushing the lever (302) to achieve a small degree of unlocking of the cylindrical pin (201); S8: The contact point separated from the workpiece surface automatically rebounds under the action of the return spring (202) and comes into contact with the workpiece surface again; S9: Repeat step S3 to complete the second locking; S10: Repeat S6 to S9 until the requirements are met; the robot's automatic hole-making end effector starts hole-making.

2. A multi-stage adaptive conformal pressing method according to claim 1, characterized in that: The amplifier (111) amplifies the signal measured by the pressure sensor (110) into a 4-20 mA current signal and feeds it back to the control system.

3. The multi-stage adaptive conformal pressing method according to claim 1, characterized in that: The effective stroke of the cylindrical pin (201) is 24.5 mm.

4. The multi-stage adaptive conformal pressing method according to claim 1, characterized in that: The baffle comprises a pin connecting plate (203) and a pin fixing plate (204), wherein the pin connecting plate (203) is provided with array-arranged circular through holes, and the pin fixing plate (204) is provided with a gourd-shaped special-shaped hole, wherein the large circular hole of the special-shaped hole has the same diameter as the regular circular through hole on the pin connecting plate (203), and is larger than the axial diameter Ra of the cylindrical pin (201) section A and smaller than the axial diameter Rc of the cylindrical pin (201) section C, and the special-shaped hole is provided with a large circular hole. The aperture of the small circular hole is larger than the axial diameter Rb of the cylindrical pin (201) section B and smaller than the axial diameter Ra of the cylindrical pin (201) section A; the plate surface sizes of the pin connecting plate (203) and the pin fixing plate (204) are equal, and when the two are completely overlapped, the minimum aperture of the through hole is shown to be in clearance fit with the cylindrical pin (201) section B, and the pin connecting plate (203) and the pin fixing plate (204) are overlapped and fixed to each other to position the cylindrical pin (201).

5. A multi-stage adaptive conformal pressing method according to claim 4, characterized in that: The pin connecting plate (203) and the pin fixing plate (204) are connected by screws after being completely overlapped, and the two are placed together in the reserved space of the pin base and the pin fixing block (404) to achieve clamping and fixing.

6. The multi-stage adaptive conformal pressing method according to claim 1, characterized in that: The locking module (3) further comprises a locking block (304) and a drive unit connecting plate (306); the lever pin (303) passes through the lever (302) and the locking block (304) respectively, and is clearance-matched with the lever (302) and the locking block (304), providing a fulcrum for the rotation of the lever (302); the locking block (304) is fixedly connected to the base module (4); the drive unit (301) is fixed on the drive unit connecting plate (306), and then the assembly of the drive unit (301) and the drive unit connecting plate (306) is positioned on the base module (4) through three-side positioning.

7. The multi-stage adaptive conformal pressing method according to claim 6, characterized in that: The locking block (304) is fixedly connected to the pin fixing block (404); the driving unit (301) and the driving unit connecting plate (306) are fixed together on the driving unit rear cover (403) and locked by screws.

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