Aircraft coordinate system-based offline programming method for robot mirror image drilling machining

Abstract

The invention discloses an aircraft coordinate system-based robot mirror image drilling processing off-line programming method, which specifically comprises the following steps of: establishing an aircraft coordinate system, and extracting drilling geometric parameters; constructing a space mirror plane and a normal vector thereof, and determining a relative pose between the aircraft coordinate system and the robot 1 base coordinate system; projecting and calculating the position of a mirror image hole; rotating around an aircraft coordinate system to calculate a mirror image hole attitude; determining a hole making process according to the calculated mirror image hole poses; building a double-robot simulation environment; generating an intermediate file in combination with the process information; and a simulation machining path is determined, and a final machining program is output. According to the method, after the position and posture information of the machining holes in one side of the airplane is generated, mirror image deviation and mirror image rotation are carried out, so that the positions and postures of a series of holes in the mirror image symmetry plane of the machining face are obtained, it is guaranteed that hole machining is consistent and effective while the workload is relieved, the programming process is simplified, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, and in particular to an off-line programming method for robot mirror hole making processing based on an aircraft coordinate system. Background Art

[0002] With the rapid development of aviation technology in recent years, higher requirements have been placed on the assembly quality and lifespan of aircraft. The consistency and verticality of aircraft connection holes, which are key factors affecting fatigue life and safety, are increasingly difficult to meet with current high-quality requirements through traditional hole-making processing technology. Industrial robots, as the carriers of digitalization and intelligence in high-end manufacturing, are increasingly widely used in the field of automatic hole-making in aircraft components due to their high flexibility, adaptability, low cost, and easy integration. Through continuous technological accumulation and application, robotic automatic hole-making technology has been well developed. Among the more well-known ones are the ONCE robotic automatic hole-making system developed by EI Corporation in the United States, the G2000 automatic drilling and riveting equipment of GEMCOR, and the RACe automatic hole-making system developed by Baojie in Germany.

[0003] Programming for robot hole making mainly includes two forms: online teaching and offline programming. Online teaching requires the operator to move the robot to a certain target point and then record the position. The accuracy of the robot path trajectory can only rely on the instructor's visual inspection. This method is inefficient and has many uncertain factors, which can easily cause large errors. Patent CN105171745B introduces a robot offline programming system. By establishing a virtual simulation scene, the preset robot and workpiece model identifies the workpiece and processing information to generate the robot trajectory, and after simulation confirmation, a robot-recognizable program is generated. However, although this offline programming method can generate preliminary hole-making postures using the digital model features of the product, the processing points need to be adjusted and re-planned one by one subsequently, which is a large workload and difficult to ensure consistent and effective hole-making processing. Therefore, this paper proposes an offline programming method for robot mirror hole-making processing based on the aircraft coordinate system, which aims to avoid repeated robot programming operations to improve production efficiency. Summary of the Invention

[0004] In response to the problems existing in the above-mentioned prior art, the present invention proposes an offline programming method for robot mirror hole making processing based on the aircraft coordinate system. After generating the processing hole posture information on one side of the aircraft, mirror offset and mirror rotation are performed to obtain the positions and postures of a series of holes on the mirror symmetry plane of the processing surface, so as to reduce the workload and ensure that the hole making processing is consistent and effective, thereby simplifying the programming process and improving production efficiency.

[0005] In order to achieve the above technical objectives, the present invention provides the following technical solutions:

[0006] An off-line programming method for robot mirror hole making based on an aircraft coordinate system, specifically comprising:

[0007] S1. Establishing an aircraft coordinate system and extracting the position and posture of each hole on the aircraft machined surface in the aircraft coordinate system; setting geometric parameters of each hole and storing them in a parameter data set; the geometric parameters include hole type, hole diameter, countersink angle, countersink diameter, number of hole layers, and material and thickness of each layer; the hole types include reference holes and machined holes;

[0008] S2. Environment layout; construct a plane using the two axis directions of the aircraft coordinate system and the origin O = (x0 y0 z0) as the mirror plane, and use the normal n = (a1 a2 a3) of the mirror plane as the offset direction of the mirror hole position; determine the spatial mirror plane equation based on the aircraft coordinate system and the normal n; the spatial mirror plane equation is: F(X, Y, Z) = a1(X-x0) + a2(Y-y0) + a3(Z-z0);

[0009] After the environment layout is determined, the relative position between the aircraft coordinate system and the robot 1 base coordinate system is determined using the homogeneous transformation matrix Expressed as:

[0010]

[0011] Among them, vectors n, o, and a are the components of the X, Y, and Z axes of the aircraft coordinate system in the base coordinate system of robot 1; n, o, and a form the three-dimensional posture rotation matrix representing the aircraft coordinate system relative to the base coordinate system of robot 1 x, y, and z are the projection distances from the origin of the aircraft coordinate system to the axes of the robot 1 base coordinate system;

[0012] S3, extract the reference hole or processing hole position from the parameter data set described in step S1, and obtain the posture rotation matrix of hole p1 in the base coordinate system of robot 1 The distance d from hole p1 to the mirror plane along the position offset direction is obtained by the spatial mirror plane equation in step S2, and its formula is expressed as:

[0013]

[0014] Move the original reference hole and the processed hole by a distance of 2d in the position offset direction to obtain the position of the mirror hole p2 in the base coordinate system of robot 1.

[0015] S4, extract the reference hole and the processing hole posture from the parameter data set described in step S1, convert them into the robot posture rotation matrix, and obtain the posture rotation matrix of the mirror hole p2 in the robot 1 base coordinate system.

[0016] S5, according to the position of the mirror hole p2 in the base coordinate system of robot 1 and the attitude rotation matrix Obtain the pose matrix of the mirror hole p2 in the base coordinate system of robot 1 Then according to the relative posture relationship of the two robot base coordinate systems Obtain the pose matrix of the mirror hole p2 in the robot 2 base coordinate system through homogeneous transformation

[0017]

[0018] S6, determine the hole making process corresponding to the mirror hole from the parameter data set described in step S1, and combine it with the pose matrix obtained in step S5 Finally, complete mirror hole information is obtained; the hole information includes the position and posture of the mirror hole and its process;

[0019] S7. Establish a dual-robot machining simulation environment under the DELMIA simulation module, and obtain a path simulation program for the mirror reference hole and each mirror machining hole based on the DELMIA simulation module;

[0020] S8. For the mirror reference hole, generate the final processing program of the mirror reference hole; for the mirror processing hole, load the processing technology of the current mirror processing hole, and simulate the processing path simulation program according to the processing technology, and finally generate the final processing program of the mirror processing hole.

[0021] Furthermore, the two axis directions described in step S2 can be any one of the three pairs of coordinate axes, namely, the Z-axis, the X-axis, the Z-axis, and the X-axis.

[0022] Furthermore, step S4 is specifically as follows:

[0023] Rotate symmetrically around the Z axis of the fixed frame of the aircraft coordinate system to obtain the postures of the mirror reference hole and the processed hole; obtain the posture rotation matrix of the mirror hole p2 in the base coordinate system of robot 1, which is expressed as follows:

[0024]

[0025] in, Represents the posture rotation matrix of the mirror hole p2 in the base coordinate system of robot 1; Represents the attitude rotation matrix of the aircraft coordinate system in the robot 1 base coordinate system; Represents the attitude rotation matrix of the mirror point p2 in the aircraft coordinate system; Represents the attitude rotation matrix of point p1 in the aircraft coordinate system, which can be obtained by Calculate; R(Z,π) represents a 180° rotation around the Z axis of the aircraft coordinate system fixed frame, that is

[0026] More specifically, the symmetrical rotation in step S4 is:

[0027] The posture of the reference hole and the processing hole is rotated around the z-axis axial vector of the aircraft coordinate system fixed frame to obtain the posture rotation matrix of the mirror reference hole and the mirror processing hole

[0028] Furthermore, the establishment of the dual-robot machining simulation environment in step S7 includes setting a relative posture relationship among the tooling model, the product model, the end effector and the robot model.

[0029] Furthermore, step S7 specifically includes:

[0030] S71. Convert each mirror hole information into a data format that complies with the DELMIA simulation module as an intermediate data file of the mirror hole;

[0031] S72. Perform path simulation using the DELMIA simulation module according to the intermediate data files of each mirror hole, and obtain and output the path simulation program of the mirror reference hole and each mirror processing hole.

[0032] Furthermore, in step S8, the final processing program is output in MPF ​​format.

[0033] Based on the above technical solution, the present invention has the following beneficial effects:

[0034] 1. After generating the position and posture information of the reference hole and the processed hole on one side of the aircraft, the present invention obtains the position and posture of a series of holes on the mirror symmetry plane of the processed surface through mirror offset and mirror rotation, thereby reducing the workload and ensuring consistent and effective hole-making processing, avoiding repeated robot programming operations, and improving production efficiency;

[0035] 2. Through secondary development of the DELMIA simulation environment, the invention can quickly extract the geometric parameters of each hole on the machined surface and freely set the hole-making process information;

[0036] 3. This method summarizes the geometric parameters and position and posture information of the machining surface and the symmetry surface, and loads them into the established robot mirror hole-making simulation environment. It can then realize automatic trajectory planning and obtain the simulation program of the machining surface and the symmetry surface, and automatically output the final machining program; thereby reducing labor costs and avoiding the uncertainties and errors caused by manual operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The figure is a flow chart of an offline programming method for robot mirror hole making processing based on an aircraft coordinate system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0039] Although the steps in the present invention are arranged with numbers, they are not intended to limit the order of the steps. Unless the order of the steps is clearly stated or the execution of a step requires other steps as a basis, the relative order of the steps can be adjusted. It is understood that the term "and / or" used herein refers to and covers any and all possible combinations of one or more of the associated listed items.

[0040] like Figure 1 As shown, the present invention proposes an off-line programming method for robot mirror hole making based on an aircraft coordinate system, which specifically includes the following steps:

[0041] S1. Establishing an aircraft coordinate system and extracting the position and posture of each hole on the aircraft machined surface in the aircraft coordinate system; setting geometric parameters of each hole and storing them in a parameter data set; the geometric parameters include hole type, hole diameter, countersink angle, countersink diameter, number of hole layers, and material and thickness of each layer; the hole types include reference holes and machined holes;

[0042] In this embodiment, the geometric parameters in the parameter data set can be used to determine the corresponding machining processes under different parameters, such as spindle speed and feed rate. Furthermore, for mirrored holes, no distinction is made between the reference hole and the machined hole, and both are mirrored. In the subsequent actual machining process, the machined hole is used for point planning, while the reference hole is used for error correction after visual inspection.

[0043] S2. Environment layout; construct a plane using the two axis directions of the aircraft coordinate system and the origin O = (x0 y0 z0) as the mirror plane, and use the normal n = (a1 a2 a3) of the mirror plane as the offset direction of the mirror hole position; determine the spatial mirror plane equation based on the aircraft coordinate system and the normal n; the spatial mirror plane equation is: F(X, Y, Z) = a1(X-x0) + a2(Y-y0) + a3(Z-z0);

[0044] In this embodiment, the two axis directions described in step S2 can be any one of the three pairs of coordinate axes, namely, the Z-axis, the X-axis, the Z-axis, and the X-axis.

[0045] After the environment layout is determined, the relative position between the aircraft coordinate system and the robot 1 base coordinate system is determined using the homogeneous transformation matrix Expressed as:

[0046]

[0047] Among them, vectors n, o, and a are the components of the X, Y, and Z axes of the aircraft coordinate system in the base coordinate system of robot 1; n, o, and a form the three-dimensional posture rotation matrix representing the aircraft coordinate system relative to the base coordinate system of robot 1 x, y, and z are the projection distances from the origin of the aircraft coordinate system to the axes of the robot 1 base coordinate system;

[0048] S3, extract the reference hole or processing hole position from the parameter data set described in step S1, and obtain the posture rotation matrix of hole p1 in the base coordinate system of robot 1 The distance d from hole p1 to the mirror plane along the position offset direction is obtained by the spatial mirror plane equation in step S2, and its formula is expressed as:

[0049]

[0050] Move the original reference hole and the processed hole by a distance of 2d in the position offset direction to obtain the position of the mirror hole p2 in the base coordinate system of robot 1.

[0051] S4, extract the reference hole and the processing hole posture from the parameter data set described in step S1, convert them into the robot posture rotation matrix, and obtain the posture rotation matrix of the mirror hole p2 in the robot 1 base coordinate system.

[0052] As a preferred embodiment, step S4 is specifically as follows:

[0053] Rotate symmetrically around the Z axis of the fixed frame of the aircraft coordinate system to obtain the postures of the mirror reference hole and the processed hole; obtain the posture rotation matrix of the mirror hole p2 in the base coordinate system of robot 1, which is expressed as follows:

[0054]

[0055] in, Represents the posture rotation matrix of the mirror hole p2 in the base coordinate system of robot 1; Represents the attitude rotation matrix of the aircraft coordinate system in the robot 1 base coordinate system; Represents the attitude rotation matrix of the mirror point p2 in the aircraft coordinate system; Represents the attitude rotation matrix of point p1 in the aircraft coordinate system, which can be obtained by Calculate; R(Z,π) represents a 180° rotation around the Z axis of the aircraft coordinate system fixed frame, that is

[0056] More specifically, the symmetrical rotation is:

[0057] The posture of the reference hole and the processing hole is rotated around the z-axis axial vector of the aircraft coordinate system fixed frame to obtain the posture rotation matrix of the mirror reference hole and the mirror processing hole

[0058] S5, according to the position of the mirror hole p2 in the base coordinate system of robot 1 and the attitude rotation matrix Obtain the pose matrix of the mirror hole p2 in the base coordinate system of robot 1 Then according to the relative posture relationship of the two robot base coordinate systems Obtain the pose matrix of the mirror hole p2 in the robot 2 base coordinate system through homogeneous transformation

[0059]

[0060] S6, determine the hole making process corresponding to the mirror hole from the parameter data set described in step S1, and combine it with the pose matrix obtained in step S5 Finally, complete mirror hole information is obtained; the hole information includes the position and posture of the mirror hole and its process;

[0061] S7. Establish a dual-robot machining simulation environment in the DELMIA simulation module, including: setting the relative pose relationship between the tooling model, product model, end effector, and robot model; and then obtaining the path simulation program for the mirror reference hole and each mirror machining hole based on the DELMIA simulation module;

[0062] As a preferred embodiment, step S7 is specifically as follows:

[0063] S71. Convert each mirror hole information into a data format that complies with the DELMIA simulation module as an intermediate data file of the mirror hole;

[0064] S72. Perform path simulation using the DELMIA simulation module according to the intermediate data files of each mirror hole, and obtain and output the path simulation program of the mirror reference hole and each mirror processing hole.

[0065] S8. For the mirror reference hole, generate the final processing program of the mirror reference hole; for the mirror processing hole, load the processing technology of the current mirror processing hole, and simulate the processing path simulation program according to the processing technology, and finally generate the final processing program of the mirror processing hole and output it in MPF ​​format.

[0066] In summary, the present invention proposes an offline programming method for robot mirror hole making based on the aircraft coordinate system. After generating the hole posture information of the aircraft side, mirror offset and mirror rotation are performed to obtain the positions and postures of a series of holes on the mirror symmetry plane of the processing surface, so as to reduce the workload and ensure the consistency and effectiveness of the hole making process, greatly simplifying the programming process and improving production efficiency.

[0067] It should be noted that it will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and it is intended that all variations within the meaning and range of equivalents of the claims be encompassed within the present invention. Any reference signs in the claims should not be construed as limiting the claim to which they relate.

[0068] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A robot mirror hole making processing offline programming method based on an aircraft coordinate system, characterized in that: The specific steps include: S1, establish an aircraft coordinate system, extract the position and posture of each hole of the aircraft processing surface in the aircraft coordinate system; set the geometric parameters of each hole and store them in a parameter data set; the geometric parameters include hole type, hole diameter, countersink angle, countersink diameter, number of hole layers, and material and thickness of each layer; the hole type includes reference hole and processing hole; S2, environmental layout; A plane is constructed with the two axis directions of the aircraft coordinate system and the origin O=(x0 y0 z0) as the mirror plane, and the normal n=(a1 a2 a3) of the mirror plane is used as the offset direction of the mirror hole position; the spatial mirror plane equation is determined by the aircraft coordinate system and the normal n; the spatial mirror plane equation is: F(X,Y,Z)=a1(X-x0)+a2(Y-y0)+a3(Z-z0); After the environment layout is determined, the relative position between the aircraft coordinate system and the robot 1 base coordinate system is determined, using the homogeneous transformation matrix It is expressed as: Among them, vectors n, o, and a are the components of the X, Y, and Z axes of the aircraft coordinate system in the base coordinate system of robot 1; n, o, and a form the three-dimensional posture rotation matrix representing the aircraft coordinate system relative to the base coordinate system of robot 1 x, y, and z are the projection distances from the origin of the aircraft coordinate system to the axes of the robot 1 base coordinate system; S3, extracting the reference hole and the processing hole positions from the parameter data set described in step S1, and obtaining the posture rotation matrix of hole p1 in the base coordinate system of robot 1 and The distance d from the hole p1 to the mirror plane along the position offset direction is obtained by the spatial mirror plane equation in step S2, and its formula is expressed as: Move the original reference hole and the processed hole by a distance of 2d in the position offset direction to obtain the position of the mirror hole p2 in the robot 1 base coordinate system. S4, extract the reference hole and the processing hole posture from the parameter data set described in step S1, convert them into the robot posture rotation matrix, and obtain the posture rotation matrix of the mirror hole p2 in the robot 1 base coordinate system S5, according to the position of the mirror hole p2 in the base coordinate system of robot 1 and the attitude rotation matrix Obtain the pose matrix of the mirror hole p2 in the robot 1 base coordinate system According to the relative position relationship of the two robot base coordinate systems The pose matrix of the mirror hole p2 in the robot 2 base coordinate system is obtained through homogeneous transformation S6, determine the hole making process corresponding to the mirror hole from the parameter data set described in step S1, and combine it with the pose matrix obtained in step S5 Finally, complete mirror hole information is obtained; the hole information includes the position and posture of the mirror hole and its process; S7. Establish a dual-robot machining simulation environment under the DELMIA simulation module, and obtain a path simulation program of the mirror reference hole and each mirror machining hole based on the DELMIA simulation module; S8. For the mirror reference hole, generate the final processing program of the mirror reference hole; for the mirror processing hole, load the processing technology of the current mirror processing hole, and simulate the processing path simulation program according to the processing technology, and finally generate the final processing program of the mirror processing hole.

2. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 1 is characterized in that: The two axis directions described in step S2 can be any one of the three pairs of coordinate axes, namely, the Z-axis, the X-axis, the Z-axis, and the X-axis.

3. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 1 is characterized in that: Step S4 is specifically as follows: Rotate symmetrically around the Z axis of the fixed frame of the aircraft coordinate system to obtain the posture of the mirror reference hole and the processing hole; obtain the posture rotation matrix of the mirror hole p2 in the base coordinate system of robot 1, and the formula is expressed as: in, Represents the posture rotation matrix of the mirror hole p2 in the base coordinate system of robot 1; Represents the attitude rotation matrix of the aircraft coordinate system in the robot 1 base coordinate system; Represents the attitude rotation matrix of the mirror point p2 in the aircraft coordinate system; Represents the attitude rotation matrix of point p1 in the aircraft coordinate system, which can be obtained by Calculate; R(Z,π) represents a 180° rotation around the Z axis of the aircraft coordinate system fixed frame, that is 4. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 3 is characterized in that: The symmetrical rotation in step S4 is specifically: The posture of the reference hole and the processed hole is rotated around the z-axis axial vector of the aircraft coordinate system fixed frame to obtain the posture rotation matrix of the mirror reference hole and the mirror processed hole.

5. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 1 is characterized in that: The establishment of the dual-robot machining simulation environment in step S7 includes: setting the relative position and posture relationship between the tooling model, the product model, the end effector and the robot model.

6. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 1 is characterized in that: Step S7 specifically includes: S71, for each mirror hole information, convert it into a data format that complies with the DELMIA simulation module as an intermediate data file of the mirror hole; S72. Perform path simulation using the DELMIA simulation module according to the intermediate data files of each mirror hole, and obtain and output the path simulation program of the mirror reference hole and each mirror processing hole.

7. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 6 is characterized in that: The format of the intermediate data file in step S71 is an EXCEL table.

8. The offline programming method for robot mirror hole making based on aircraft coordinate system according to claim 1 is characterized in that: In step S8, the final processing program is output in MPF ​​format.

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