CN117817377A

CN117817377A - System and method for in-situ hole making and milling of outer surface of large thin-wall framework

Info

Publication number: CN117817377A
Application number: CN202410072671.2A
Authority: CN
Inventors: 薛明显; 薛贵军; 申望; 杜兆才; 施政
Original assignee: AVIC Beijing Aeronautical Manufacturing Technology Research Institute
Current assignee: AVIC Beijing Aeronautical Manufacturing Technology Research Institute
Priority date: 2024-01-18
Filing date: 2024-01-18
Publication date: 2024-04-05

Abstract

The invention belongs to the field of in-situ hole making and milling of large-scale thin-wall frameworks, and particularly relates to a system and a method for in-situ hole making and milling of the outer surface of a large-scale thin-wall framework. The system comprises a movable support, a left transfer base, a right transfer base, a transfer trolley set, an annular structure formed by left and right arc-shaped frames, a processing execution unit (comprising a hole making and milling tool head), a rotating system, a first positioning locking device (a first connecting piece at the bottom of the left and right transfer base) and a second positioning locking device (configured on a splicing surface of the annular structure). The frame structure is rigidly supported, the left and right/lower frames can be automatically combined, the frames can be divided into a plurality of frames, other frames above the frames are hung in positions to form a whole circular structure, the whole annular surface and the end face are covered, and automatic hole making and milling processing are realized. The frame can be arc-shaped or other shapes.

Description

System and method for in-situ hole making and milling of outer surface of large thin-wall framework

Technical Field

The invention belongs to the field of in-situ hole making and milling of large-scale thin-wall frameworks, and particularly relates to a system and a method for in-situ hole making and milling of the outer surface of a large-scale thin-wall framework.

Background

In the field of hole making and milling of large thin-wall frameworks, a series of problems exist in the prior art. The existing general machine tool and the technical scheme have the disadvantages of huge volume, low coverage rate, huge and heavy equipment, and being only capable of making holes on the left side and the right side, and being only capable of being installed at fixed positions, and are not suitable for assembly environments. Meanwhile, the stability and consistency of the equipment are low, the equipment is complex in assembly, long in time consumption, poor in rigidity, low in hole making precision, relatively low in hole making coverage rate and efficiency, and unsuitable for milling. The main reasons for the problems are that a circular track module consisting of a flexible annular track, an arc track adsorbed on the outer circumferential surface of a large thin-wall framework and the like is adopted, so that the system is complex in structure and complex in assembly, and the state stability and consistency achieved by butt joint each time are poor due to the fact that the number of connected track modules is large.

Meanwhile, the installation problem of the existing equipment on the outer surface of the large thin-wall framework is also remarkable, the installation of the flexible rail and the adsorbed arc-shaped rail requires frequent high-altitude operation of operators, the safety risk is high, and the height of the supporting legs connecting the two circles of guide rails and the outer surface of the large thin-wall framework is repeatedly adjusted and calibrated for multiple times. These problems seriously affect the stability of the equipment and the efficiency of the hole making and milling processes.

In addition, because structures such as a sucker and a retainer connecting rod of the connecting track occupy most of the butt joint area of the large thin-wall framework in the existing equipment, the hole making coverage rate is low, and because the sucker is limited in self adsorption force, the hole making speed and the hole making precision are limited, and the whole rigidity is weak, the device is not suitable for milling.

In general, the prior art has the above-described problems with in-situ hole making, milling of the outer surface of large thin-walled frameworks, and a new system and method is needed to address these problems.

Disclosure of Invention

First, the technical problem to be solved

The invention mainly aims at solving the problems that the existing large-sized thin-wall framework in-situ hole making and milling system has huge volume, poor stability, complicated assembly, low efficiency, low hole making precision, inapplicability to milling and the like.

(II) technical scheme

In order to achieve the above object, a first aspect of the present invention provides a system for in-situ drilling and milling an outer surface of a large thin-wall frame, comprising:

the mobile support device comprises at least one group of left transfer base, right transfer base, left transfer trolley and right transfer trolley; the left transfer base and the right transfer base are respectively arranged on lifting parts of the left transfer trolley and the right transfer trolley, the left transfer trolley and the right transfer trolley have lifting functions, the left transfer trolley and the right transfer trolley can be shared, after the left transfer base and the right transfer base are connected with the ground, the left transfer base and the right transfer trolley can be made into a form of separating the base from the transfer trolley, and the transfer trolley is connected and fixed with the left transfer base and the right transfer base through a connecting and locking device;

the left arc-shaped frame and the right arc-shaped frame are arranged on the left transfer base, the left arc-shaped frame and the right arc-shaped frame can be spliced to form an annular structure, and the appearance can be made into an arc-shaped, square or other forms of structures;

the machining execution unit is arranged on the annular structure and at least comprises a hole making and milling tool head, two mutually perpendicular rotary servo shafts and three linear feed shafts, and realizes five-axis linkage and independent feeding machining of the hole making and milling tool head with the servo shafts on the annular structure;

the rotating system is arranged on the annular structure and used for guiding and driving the processing execution unit to rotate along the annular structure;

the first positioning locking device comprises a plurality of first connecting pieces, is configured at the bottoms of the left transfer base and the right transfer base and is used for positioning and locking the left transfer base and the right transfer base on preset positioning points;

the second positioning and locking device is configured on the splicing surface of the annular structure and is used for positioning, locking and splicing the left arc-shaped frame and the right arc-shaped frame.

Further, the rotating system comprises a gear ring, an annular track, a gear meshed with the gear ring and a sliding component matched with the annular track, wherein the sliding component is installed on the machining execution unit, a driving component is arranged on the machining execution unit, and the output end of the driving component is connected with the gear and used for providing power to enable the machining execution unit to rotate along the annular structure.

Further, the second positioning and locking device comprises a plurality of second connecting pieces and second butt joint pieces, wherein the second connecting pieces are installed on the splicing end face of the left arc-shaped frame, the second butt joint pieces are installed on the splicing end face of the right arc-shaped frame, and the second connecting pieces are matched with the second butt joint pieces and are used for detachably positioning and connecting the left arc-shaped frame and the right arc-shaped frame.

Further, the device further comprises a third positioning locking device, wherein the third positioning locking device comprises a plurality of third connecting pieces which are arranged on the bottoms of the left rotating base and the right transferring base, and a plurality of third butt joint pieces which are arranged at the upper ends of the left transferring trolley and the right transferring trolley, and the third butt joint pieces are used for detachably connecting the left rotating base with the left transferring trolley and the right transferring base with the right transferring trolley.

Further, the device further comprises a splicing driving component, the splicing driving component comprises a sliding rail and a screw shaft which are arranged on the right-side transferring base, and a sliding block and a sliding seat which are arranged on the right-side arc-shaped frame, the sliding block is slidingly arranged on the sliding rail, one end of the screw shaft penetrates through the sliding seat and is in threaded arrangement with the sliding seat, and the other end of the screw shaft is connected with an output shaft or a hand wheel of the motor.

Further, the left arc-shaped frame and the right arc-shaped frame are formed by splicing a plurality of arc-shaped frames, and can also be formed by splicing left and right independent arc-shaped frames in a butt joint mode.

In order to achieve the above purpose, a second aspect of the present invention provides a calibration method for in-situ hole making and milling processing of an outer surface of a large thin-wall framework, which is implemented by using the system, and the system further comprises a data processing unit connected with the stay wire type displacement sensor; the method comprises the following steps:

a stay wire type displacement sensor is arranged on one end point A of an annular structure formed by a left arc-shaped frame and a right arc-shaped frame, and the end point A is measured to a stress point B on the annular structure _T A relative position change between;

applying an external force to deform the annular structure to cause the point B _T Move to point B _P ；

According to displacement variation delta x of stay wire type displacement sensor indication, determining a deformed point B _T To point B _P Actual distance lp=l between _T +Δx, where point A and point B _T The distance between them is L _T ；

Modeling deformation of the annular structure by the above-described action using finite element analysis software to determine point B _T And point B _P Is a relative position of (2);

and obtaining the angle deviation after arc deformation by geometric calculation and cosine theorem, and correcting the processing path according to the angle deviation.

Further, the external forces include structural gravity, end effector gravity, and cutting force resistance.

Further, the step of obtaining the angle deviation after arc deformation by combining the cosine theorem through geometric calculation comprises the following steps:

in triangle DeltaAB _T B _P The edge AB is determined by cosine theorem _T Sum edge AB _P An included angle gamma;

calculating the center point O of the annular structure to point A and point B _T Formed isosceles triangle delta OAB _T Middle side OA and side OB _T An included angle delta;

triangle delta OAB using cosine theorem _P In the method, the side length OB is calculated according to the known side length and the known included angle _P ；

In triangle ΔOB _T B _P In which the cosine theorem is applied to calculate the edge OB _T With edge OB _P The actual included angle alpha+beta is obtained through the geometric relationship;

according to triangle delta OAB _T Isosceles threeThe angular property calculates the actual rotation angle omega _P ，Wherein omega _T A rotation angle planned according to a theoretical model is provided;

and finally, calculating the hole forming positioning error generated on the arc length of the annular structure due to the deformation of the annular structure.

(III) beneficial effects

Compared with the prior art, the system and the method for in-situ hole making and milling of the outer surface of the large thin-wall framework have the following beneficial effects:

1. miniaturized design and efficient processing: compared with the traditional huge general machine tool, the system adopts the combination of the movable support device, the annular structure and the processing execution unit, thereby realizing the miniaturization design of the system. Compared with a flexible rail, the system has high rigidity, each shaft can be rapidly moved and processed with high precision, and the processing efficiency is improved through the rotation of the annular structure and the flexibility of the movable support, so that the in-situ hole making and milling processing are more efficient.

2. High stability and hole making precision: by adopting the first positioning locking device and the second positioning locking device, the problem of poor equipment stability in the prior art is effectively solved. The stability of the system in the processes of hole making and milling on a plane and a space curved surface is ensured, and the hole making precision and consistency are improved.

3. Simplified assembly and operation: the system adopts the combination of the annular structure and the movable support, reduces the assembly steps and reduces the complexity of equipment assembly. This makes the apparatus easier to operate, shortens the assembly time, and improves the production efficiency.

4. And (3) safety is improved: through carrying out automatic positioning connection at the extreme point of annular structure, can effectively avoid the potential safety hazard of high altitude construction and frequent adjustment. This not only improves the safety of the operation of the device, but also reduces the risk for the operator.

5. Automatic calibration and correction path: by adopting the stay wire type displacement sensor and the finite element analysis software in the calibration method, the system can realize real-time monitoring of the deformation of the annular structure and automatic correction of the processing path, and the accuracy and consistency of processing are improved.

In summary, the invention solves a series of problems existing in the prior art in the field of in-situ hole making and milling processing of the large thin-wall framework, and has the beneficial effects of miniaturization, efficient processing, high stability, simplified operation, safety improvement, automatic correction and the like of equipment.

Drawings

FIG. 1 is a schematic view of an in-situ hole making and milling system for an outer surface of a large thin-walled frame as disclosed herein.

Fig. 2 is a schematic perspective view of an in-situ hole making and milling system for the outer surface of a large thin-walled frame as disclosed in the present application.

Fig. 3 is a schematic structural diagram of a left-right butt joint mode disclosed in the application.

Fig. 4 is a schematic structural diagram of a left, right and upper butt joint mode disclosed in the application.

Fig. 5 is a schematic view of a construction of an automated transport base form as disclosed herein.

Fig. 6 is a schematic structural view of a transfer vehicle and an arc frame independent of each other.

Fig. 7 is a schematic bottom view of a left transfer base disclosed in the present application.

Fig. 8 is a schematic view of a partial structure of a left arc frame disclosed in the present application.

FIG. 9 is a schematic diagram of a corner error analysis disclosed in the present application.

Reference numerals shown in the drawings:

10. a left transfer base; 11. a left transfer vehicle; 12. a left arc frame; 12-1, upper left arc frame; 12-2, lower left arc frame;

20. a right side transfer base; 21. a right side transfer vehicle; 22. a right arc frame; 22-1, upper right arc frame; 22-2, lower right arc frame;

30. a processing execution unit;

40. a rotating system; 41. a gear ring; 42. an endless track;

50. a first positioning and locking device; 51. a first connector;

60. a second positioning and locking device; 61. a second connector; 62. a second docking member;

70. a third positioning and locking device; 71. a third connecting member;

80. splicing the driving components; 81. a slide rail; 82. a screw shaft; 83. and a hand wheel.

Detailed Description

The following detailed description of the present invention, taken in conjunction with the accompanying drawings, will clearly and fully describe the technical solutions of the embodiments of the present invention, it being evident that the described embodiments are only some, but not all, embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When a component is considered to be "connected" to another component, it can be directly connected to the other component or intervening components may also be present. When an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1-8, a schematic structural diagram of an in-situ hole-making and milling system for an outer surface of a large thin-wall framework according to a preferred embodiment of the present application is shown. In the embodiment shown in fig. 1-8, the processing system includes:

a mobile support device comprising at least one set of a left transfer base 10, a right transfer base 20, a left transfer car 11 and a right transfer car 21; the left transfer base 10 and the right transfer base 20 are respectively installed on lifting components of the left transfer trolley 11 and the right transfer trolley 21, the left transfer trolley 11 and the right transfer trolley 21 have lifting functions, and the left transfer base 10 and the right transfer base 20 can be respectively driven to descend by the lifting components so as to be positioned and locked on a preset positioning point;

the left arc-shaped frame 12 arranged on the left transfer base 10 and the right arc-shaped frame 22 arranged on the right transfer base 20 can be spliced to form an annular structure in the left arc-shaped frame 12 and the right arc-shaped frame 22, namely after the left transfer base 10 and the right transfer base 20 are positioned and locked at preset positioning points, the left arc-shaped frame 12 and the right arc-shaped frame 22 can be butted to form a full-circle annular structure, and the whole process is convenient and quick, short in time and high in efficiency;

a machining execution unit 30 mounted on the annular structure and including at least a hole making and milling tool head;

the rotating system 40 is arranged on the annular structure and is used for guiding and driving the machining execution unit 30 to rotate along the annular structure, so that the machining execution unit 30 realizes high-precision hole making and milling;

the first positioning and locking device 50 comprises a plurality of first connectors 51, which are arranged at the bottoms of the left transfer base 10 and the right transfer base 20 and are used for positioning and locking the left transfer base 10 and the right transfer base 20 on preset positioning points;

the second positioning and locking device 60 is configured on the splicing surface of the annular structure, and is used for positioning and locking the left arc-shaped frame 12 and the right arc-shaped frame 22.

The working process of the in-situ hole making and milling system for the outer surface of the large thin-wall framework is as follows:

the left and right transfer bases 10 and 20 are mounted on respective transfer vehicles, and the left and right arc frames 12 and 22 are respectively disposed on the left and right transfer bases 10 and 20 or mounted after reaching a predetermined position; the movable support device moves to a preset position, and the left transferring base 10 and the right transferring base 20 are respectively lowered by the lifting component to be positioned and locked on preset positioning points; the left arc frame 12 and the right arc frame 22 are spliced into an annular structure and fixedly connected through a second positioning and locking device 60; the rotation system 40 guides and drives the machining execution unit 30 to rotate along the annular structure, and high-precision hole making and milling are realized in the machining process; the on-site processing operation of the outer surface of the large thin-wall framework is ensured, and meanwhile, the processing precision and efficiency are also ensured.

In the present embodiment, as shown in fig. 8, the rotation system 40 includes a ring gear 41, an annular rail 42, and a gear meshing with the ring gear 41 and a sliding member engaged with the annular rail 42, wherein the annular rail 42 is a rail formed along an annular structure for supporting and guiding the movement of the sliding member; the gear meshes with the ring gear 41 so that the gear, when driven, can drive the machining execution unit 30 to rotate along the annular track 42; the sliding component is mounted on the processing execution unit 30 and is matched with the annular rail 42, so that the processing execution unit 30 can stably move along the annular rail 42, a driving component is arranged on the processing execution unit 30, the output end of the driving component is connected with a gear, and the driving component can provide power through the connection, so that the processing execution unit 30 can rotate along an annular structure.

The second positioning and locking device 60 includes a plurality of second connecting pieces 61 and a second abutting piece 62, the second connecting pieces 61 are installed on the splicing end face of the left arc-shaped frame 12, the second abutting piece 62 is installed on the splicing end face of the right arc-shaped frame 22, and the second connecting pieces 61 are matched with the second abutting piece 62, so that the left arc-shaped frame 12 and the right arc-shaped frame 22 can be detachably connected. The second detent locking device 60 allows for structural connection between the left side arcuate frame 12 and the right side arcuate frame 22, and can be automatically removed when needed, facilitating maintenance, transportation or other related operations of the apparatus.

The third positioning and locking device 70 is further included, and the third positioning and locking device 70 includes a plurality of third connectors 71 installed on the bottoms of the left rotating base 10 and the right transferring base 20, and a plurality of third butt connectors installed on the upper ends of the left transferring car 11 and the right transferring car 21, and is used for detachably connecting the left rotating base 10 with the left transferring car 11, and is used for detachably connecting the right transferring base 20 with the right transferring car 21.

The third positioning and locking device 70 works: when the left rotating base 10 and the left transfer trolley 11, and the right transfer base 20 and the right transfer trolley 21 need to be connected, the third connecting piece 71 and the third butt-joint piece are mutually matched, so that the left rotating base 10 and the left transfer trolley 11, and the right transfer base 20 and the right transfer trolley 21 can be firmly connected together; when disassembly is required, the connector can be easily separated, so that the left swivel base 10 and the left transfer car 11, and the right transfer base 20 and the right transfer car 21 can be separated.

The embodiment further comprises a splicing driving part 80, wherein the splicing driving part 80 comprises a sliding rail 81 and a screw rod shaft 82 which are arranged on the right side transferring base 20, and a sliding block and a sliding seat which are arranged on the right side arc-shaped frame 22, the sliding block is slidingly arranged on the sliding rail 81, one end of the screw rod shaft 82 passes through the sliding seat and is in threaded arrangement with the sliding seat, and the other end of the screw rod shaft is connected with an output shaft or a hand wheel 83 of a motor; when the motor is started or the hand wheel 83 is manually operated, the rotation of the screw shaft 82 causes the sliding block to move on the sliding rail 81, so that the relative movement of the right arc-shaped frame 22 is driven, and after the right transfer base 20 is positioned and locked at a preset positioning point, a gap is reserved between the right arc-shaped frames 22, and at the moment, the right arc-shaped frames 22 can be driven to move, so that the butt joint process is realized.

In the present embodiment, the left side arc frame 12 and the right side arc frame 22 are each formed by splicing a plurality of arc frames, such as an upper left arc frame 12-1, a lower left arc frame 12-2, an upper right arc frame 22-1 and a lower right arc frame 22-2.

The arc-shaped frame of the present embodiment has various basic forms as follows:

in the first form, as shown in the left-right butt joint of figures 3 and 5, a left transfer base 10, a left lower arc-shaped frame 12-2 and a left upper arc-shaped frame 12-1 fixed on the left transfer base are automatically transferred to a hole making and milling position on the outer surface of a large thin-wall framework; the lifting component on the left side enables the left transfer base 10 to wholly descend to the first positioning locking device 50 below to enter the position and lock; the right transferring base 20, the right lower arc-shaped frame 22-2 and the right upper arc-shaped frame 22-1 which are arranged on the right transferring base are automatically transferred to a hole making and milling position on the outer surface of the large thin-wall framework; the lifting component on the right side integrally descends the right side transfer base 20 to the first positioning locking device 50 below to enter and lock; at this time, the lower right arc frame 22-2 and the upper right arc frame 22-1 are positioned at the right side of the sliding rail 81, the second butt joint part 62 on the butt joint surface is in a state of being separated from the second connecting part 61 of the lower left arc frame 12-2 and the upper left arc frame 12-1 by a certain distance, at this time, the sliding block is moved on the sliding rail 81 by starting a motor on the right side or manually operating the hand wheel 83, so as to push the lower right arc frame 22-2 and the upper right arc frame 22-1 to integrally butt joint the lower left arc frame 12-2 and the upper left arc frame 12-1, and the second butt joint part 62 on the butt joint surface and the second connecting part 61 are automatically locked and finally positioned, thereby completing the assembly and butt joint of the two arc frames.

The left transfer trolley 11, the right transfer trolley 21 and the upper frame are mutually independent units, and as shown in fig. 6, the left transfer trolley 11 supports and locks the left transfer base 10 and automatically transfers to a hole making and milling position on the outer surface of the large thin-wall framework, namely a preset positioning point I; the lifting component of the left transfer car 11 is configured to put the left first positioning and locking device 50 of the left transfer base 10 which is wholly lowered to the lower side into position and lock the left transfer car 11 and the left transfer base 10 (namely, the third connecting piece 71 and the third butting piece in the third positioning and locking device 70 are separated), and the rear left transfer car 11 is evacuated.

The right transfer trolley 21 supports and locks the right lower arc-shaped frame 22-2 and the right upper arc-shaped frame 22-1, and automatically transfers the frames to a hole making and milling position on the outer surface of the large thin-wall framework; the lifting component configured on the right transfer trolley 21 brings the right transfer base 20 into position and locks the right first positioning and locking device 50 which is wholly lowered to the lower side, the right transfer trolley 21 is separated from the right transfer base 20 (i.e. the third connecting piece 71 and the third butting piece in the third positioning and locking device 70 are separated), and the splicing process is performed after the right transfer trolley 21 is evacuated, and the splicing process is consistent with the splicing process of the first form, and is not repeated here.

Form three, for the change of arc frame quantity, the below location form is based on basic form one, two.

Referring to fig. 4, the modification is to make the left side arc frame 12 into one or several arc frames, such as the lower left arc frame 12-2 and the upper left arc frame 12-1, and make the right side arc frame 22 into one or several arc frames, such as the lower right arc frame 22-2 and the upper right arc frame 22-1; the left lower arc-shaped frame 12-2 and the right lower arc-shaped frame 22-2 are butted, positioned and locked left and right in the mode of the first mode or the second mode, then the upper left upper arc-shaped frame 12-1 and the upper right arc-shaped frame 22-1 are hoisted to the butted left lower arc-shaped frame 12-1 and the right lower arc-shaped frame 22-2, and after positioning and locking are completed, the whole circle butting assembly of the arc-shaped frames is completed; because only the upper module needs manual hoisting alone, be equipped with the deflector on the arc frame in below right side, do not need the high altitude construction of operating personnel, factor of safety is high, and the operation time is short, and installation quality is better.

In the in-situ hole making and milling system of the embodiment, as the number of the component modules is small, the number of intermediate links is small, and the rigidity of the equipment is high; the arc-shaped frames are all arranged on the prefabricated foundation, the rigidity transmissibility of the foundation and the frames is good, a good foundation is provided for high-quality hole making and milling, and because equipment is not required to be fixed on the outer circumferential surface of the large thin-wall framework, not only can all the outer circumferential surfaces be covered and processed, but also the end surfaces of the large thin-wall framework can be overhanging out to carry out milling processing on the end surfaces of the large thin-wall framework, and the coverage rate is high; the whole rigidity of the equipment is good, the transposition and hole making milling processing can be quickly carried out, and the processing efficiency is high; in addition, because the rigidity of the equipment is high, the milling machine is suitable for milling the outer circumferential surface of the whole large thin-wall framework; the equipment does not need to be fixed on the outer circumferential surface of the large thin-wall framework, so that the system can be arranged at the end surface of the large thin-wall framework to mill the end surface with high precision.

In this embodiment, the machining execution unit 30 is an automatic hole-making and milling actuator, and can perform circular motion (Y direction) along the assembled whole circular arc frame to perform hole-making and milling on the curved surface of the large thin-wall framework. The automatic hole making and milling actuator comprises two rotating shafts A and B and three linear shafts (X axis, Z axis and W axis), wherein the X axis is parallel to the central line of the large thin-wall component, the Z axis is perpendicular to the surface of the large thin-wall component, the W axis is parallel to the Z axis, and the W axis is the hole making and milling main shaft hole making feeding shaft. Each shaft of the automatic hole making and milling actuator is provided with a feedback element to form a measurement feedback system; the control system is used for controlling, so that high-precision five-axis linkage and positioning of an automatic hole making and milling actuator can be realized, and the W axis provided with the feedback element can realize high-precision hole making and milling feeding on a curved surface of a large thin-wall framework.

The embodiment also provides a calibration method for in-situ hole making and milling processing of the outer surface of the large thin-wall framework, which is realized by using the system, and the system also comprises a data processing unit which is connected with the stay wire type displacement sensor; the method comprises the following steps:

step 1, a stay wire type displacement sensor is arranged on one end point A of an annular structure formed by a left arc-shaped frame and a right arc-shaped frame and is connected to a stress point B on the annular structure _T Measuring the stress point B from the end point A to the annular structure _T The relative position between the two points A and B is not affected by the gravity of other arc-shaped frame structures, the gravity of an actuator, the gravity of the actuator and the like _T The distance between them is L _T (in fig. 9, left and right arc frames in an initial state are indicated by broken lines).

Step 2, applying external force to deform the annular structure to lead to point B _T Move to point B _P 。

Step 3, determining the deformed point B according to the displacement variation delta x of the stay wire type displacement sensor _T To point B _P Actual distance lp=l between _T +Δx, where point A and point B _T The distance between them is L _T 。

It will be appreciated that when point B on the left and right arc frames _T When the frame is deformed by external forces such as the gravity of other frame structures, the gravity of the end effector, and the cutting force resistance (in fig. 9, the deformed state of the frame is shown by solid lines), point B _T Move to point B _P The change of the indication of the stay wire type displacement sensor is delta x, point A and point B _P The distance between them can be expressed as: lp=l _T +Δx。

Step 4, using finite element analysis software to simulate deformation of the annular structure caused by the action so as to determine the point B _T And point B _P Is used for the relative position of the two parts.

And 5, obtaining the angle deviation after arc deformation by combining geometric calculation and a cosine theorem, and correcting the processing path according to the angle deviation.

Specifically, the deformation of the frame due to the gravity of other frame structures, the gravity of the end effector and the like can be calculated by using finite element analysis software, and the B in FIG. 9 can be determined _T B _P Is of a size and orientation of (c). In triangle DeltaAB _T B _P Middle, side length AB _T 、AB _P And B _T B _P It is known that the edge AB can be calculated by using the cosine law _T Sum edge AB _P Included angle gamma:

in triangle delta OAB _T In the side length OA and the side length OB _T All are R, the side length AB _T From this, edge OA and edge OB can be calculated _T Is included in the angle delta:

in triangle delta OAB _P In the middle, side length OA and side length AB _P Both sides OA and AB are known _P The angle of (2) is also known, and the cosine law can be used to calculate the side length OB _P ：

In triangle ΔOB _T B _P Middle, side length OB _T Length of edge OB _P And side length B _T B _P It is known that edge OB can be calculated using the cosine theorem _T And edge OB _P Included angle beta:

in triangle delta OAB _T In the side length OA and the side length OB _T Are all R, thus triangle delta OAB _T Is isosceles triangle, thereby it can be seen that:

α+β＝180°-2δ

in summary, in the arc-shaped frame AB _T When the angle alpha and the angle beta are planned to be rotated according to a theoretical model, the angle alpha is actually rotated due to the deformation of the arc-shaped frame. Can be approximately considered to be converted into omega according to the theoretical model planning _T At the time of actual rotation of angle omega _P Is that

Thus, the actual rotated angle omega _P In the case of a positional error Deltax in the arc length of the arc-shaped frame _P Is that

Because the angle error is smaller, the arc length error is used for replacing the chord length error, and the generated error is extremely small, delta x _P Can be used as positioning error of hole making.

The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned. Furthermore, it is evident that the word "comprising" does not exclude other elements or steps, and that the singular does not exclude a plurality. Several of the units or means recited in the apparatus claims may also be embodied by one and the same unit or means, either in software or hardware. The terms first, second, etc. are used to denote a name, but not any particular order.

The above embodiments are only for illustrating the technical solution of the present application and not for limiting, and although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present application may be modified or substituted equally without departing from the spirit and scope of the technical solution of the present application.

Claims

1. An in-situ hole making and milling system for the outer surface of a large thin-wall framework is characterized by comprising the following components:

the mobile support device comprises at least one group of left transfer base, right transfer base, left transfer trolley and right transfer trolley; the left transfer base and the right transfer base are respectively arranged on lifting parts of the left transfer trolley and the right transfer trolley;

the left arc-shaped frame and the right arc-shaped frame are arranged on the left transfer base and the right arc-shaped frame are arranged on the right transfer base, and the insides of the left arc-shaped frame and the right arc-shaped frame can be spliced to form an annular structure;

the machining execution unit is arranged on the annular structure and at least comprises a hole making tool head and a milling tool head;

2. The system for in-situ hole making and milling of the outer surface of a large thin-wall framework according to claim 1, wherein the rotating system comprises a gear ring, an annular track, a gear meshed with the gear ring and a sliding component matched with the annular track, the sliding component is installed on the processing execution unit, a driving component is arranged on the processing execution unit, and the output end of the driving component is connected with the gear for providing power to enable the processing execution unit to rotate along the annular structure.

3. The system for in-situ hole making and milling of the outer surface of a large thin-wall framework according to claim 1, wherein the second positioning and locking device comprises a plurality of second connecting pieces and second butting pieces, the second connecting pieces are installed on the splicing end face of the left arc-shaped frame, the second butting pieces are installed on the splicing end face of the right arc-shaped frame, and the second connecting pieces are matched with the second butting pieces and are used for detachably positioning and connecting the left arc-shaped frame and the right arc-shaped frame.

4. The system of claim 1, further comprising a third positioning and locking device, wherein the third positioning and locking device comprises a plurality of third connectors mounted on the bottoms of the left rotating base and the right transferring base, and a plurality of third butt connectors mounted on the upper ends of the left transferring truck and the right transferring truck, wherein the third butt connectors are used for detachably connecting the left rotating base with the left transferring truck, and the right transferring base with the right transferring truck.

5. The system for in-situ hole making and milling of the outer surface of a large thin-wall framework according to claim 1, further comprising a splicing driving component, wherein the splicing driving component comprises a sliding rail and a screw shaft which are installed on the right transfer base, a sliding block and a sliding seat which are installed on the right arc-shaped framework, the sliding block is installed on the sliding rail in a sliding manner, one end of the screw shaft penetrates through the sliding seat and is in threaded arrangement with the sliding seat, and the other end of the screw shaft is connected with an output shaft or a hand wheel of a motor.

6. The system for in-situ drilling and milling of the outer surface of a large thin-walled framework of claim 1, wherein the left and right arc frames are each formed by splicing a plurality of arc frames.

7. The calibration method for in-situ hole making and milling of the outer surface of the large thin-wall framework is characterized by comprising the system as set forth in any one of claims 1-6, and further comprising a data processing unit connected with the stay wire type displacement sensor; the method comprises the following steps:

8. The method of claim 7, wherein the external force comprises structural gravity, end effector gravity, cutting force resistance.

9. The method of claim 7, wherein the step of deriving the angular deviation after the arc deformation by geometric calculation in combination with the cosine law comprises:

according to triangle delta OAB _T The nature of isosceles triangle calculates the actual rotation angle omega _P ，Wherein omega _T A rotation angle planned according to a theoretical model is provided;