Positioning method and device for drilling actuator

Abstract

The invention discloses a drilling actuator positioning method and device, and the method comprises the steps: S1, dividing a drilling region into a plurality of sub-regions through offline programming software based on robot accessibility and equipment interference analysis; s2, establishing a robot tool coordinate system; and S3, a four-point method is adopted to establish a robot base coordinate system in a regional mode. The invention relates to the technical field of hole making actuators. According to the drilling actuator positioning method and device, soft contact can be achieved and machining vibration can be relieved by arranging the pressing mechanism, the floating pressing head can press the surfaces of different types and different curvatures in a self-adaptive mode, the tiny position deviation between the pressing head and the workpiece is automatically compensated, and the machining precision is improved. When the pressing head encounters the conditions that hole sites are not completely centered and workpiece tolerances are different in the downward pressing process, the automatic floating pressing head can achieve horizontal fine adjustment under the condition that manual intervention is not needed, it is guaranteed that press fitting is conducted smoothly, and the product percent of pass is greatly increased.

Description

Technical Field

[0001] This invention relates to the field of hole-making actuator technology, specifically to a hole-making actuator positioning method and apparatus. Background Technology

[0002] Hole-making actuators are end effectors used in industrial robots or automated equipment to complete hole-making operations. They are mainly used in precision machining fields such as aerospace and automotive manufacturing. Core functions include: Multifunctionality: Supporting drilling, spiral milling, countersinking, automatic pin insertion, and gluing, with some models integrating with ultrasonic vibration systems to improve machining quality; High precision: Achieving precise hole positioning through vision measurement systems and digital-to-analog conversion technologies to ensure machining accuracy; Collaborative operation: In a dual-robot collaborative system, functions such as clamping and positioning, and chip removal can be achieved, improving work efficiency. Key technologies include: Communication and control: Requires efficient communication with the robot control system (such as UMAC or PLC) to ensure accurate command execution; Error correction: Compensating for positional deviations during machining through on-site calibration and point correction technologies. Application scenarios mainly involve hole-making operations in complex structural components such as aircraft and missiles, including the machining of high-precision parts such as aero-engine blades and fuselage frames.

[0003] Existing hole-making actuators are typically used for making holes in precision components such as aircraft and missiles. Therefore, absolute stability and accuracy are required. However, when making holes in irregularly shaped parts with curved surfaces, the existing hole-making actuators are prone to misalignment with the hole position after the pressure head descends, resulting in inconsistent workpiece tolerances.

[0004] Therefore, we are now designing positioning methods and devices for drilling actuators that can improve drilling efficiency and quality to address these shortcomings. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a positioning method and apparatus for a hole-making actuator, which solves the problem of inconsistent tolerances that easily occur during the processing of existing hole-making actuators.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a positioning method for a hole-making actuator, comprising a robot hole-making system coordinate system, specifically including the following steps: S1. Based on robot reachability and equipment interference analysis, the hole-making area is divided into several sub-regions using offline programming software; S2. Establish the robot tool coordinate system; S3. Establish the robot's base coordinate system by dividing the region using the four-point method; S4. Calibrate the reference point and obtain its error; S5. Import the hole position information file and reference point error into the offline programming software, input the processing parameters to generate the hole making program, and download it to the robot.

[0007] Preferably, in step S2, a robot tool coordinate system is established, and the wall panel hole information is extracted and simulation coordinate points are generated using offline programming software; Based on the robot's workspace and equipment layout, motion simulation and path planning are performed to divide the drilling area. The robot body is moved using a motion platform to place the target area in the optimal workspace. Finally, the industrial robot precisely positions the end effector through joint coordinated movement to complete the tool rotation, feeding, clamping, and chip removal auxiliary operations required for drilling.

[0008] Preferably, the coordinate system of the robot hole-making system includes the robot flange coordinate system, the robot tool coordinate system, the robot coordinate system, the assembly site coordinate system, the sub-region coordinate system, the aircraft coordinate system, and the measurement position coordinate system.

[0009] Preferably, the conversion method between the measurement position coordinate system and the assembly site coordinate system is to calculate the conversion relationship between the measured position of the target point in the measurement position coordinate system and its theoretical value in the assembly site coordinate system using the SVD least squares matching algorithm, thereby uniformly converting all measured values ​​in the measurement position coordinate system to the assembly site coordinate system.

[0010] Preferably, the steps for constructing the assembly site coordinate system are as follows: A1. Determine the coordinate axis direction: Take the direction of the robot guide rail as the X-axis direction; determine the Y and Z axes by fitting straight lines through the robot's movement along its own Y and Z axes respectively. A2. Verify orthogonality: The calculated angle between the X-axis and Y-axis is 90.02°; A3. Establish the origin and direction of the coordinate system: Select a common observation point as the origin, and use the three-point calibration method to establish the coordinate system at the assembly site; A4. Obtain the initial reference value of the observation point: Measure the typical common observation point in the measurement position coordinate system, and obtain its coordinate value in the assembly site coordinate system through coordinate transformation, which is used as the initial theoretical value.

[0011] Preferably, the clamping mechanism is installed on the left side of the drilling mechanism, the drilling mechanism includes a linear module, an electric spindle is installed on the upper part of the linear module, and a spring collet is installed on the left side of the electric spindle.

[0012] Preferably, a drill bit is mounted on the left end of the spring collet, and a servo motor is mounted on the right side of the linear module.

[0013] Preferably, the clamping mechanism includes a primary damping mechanism, a secondary damping mechanism is installed on the left side of the primary damping mechanism, and a tertiary damping mechanism is installed on the left side of the secondary damping mechanism.

[0014] This invention provides a method and apparatus for positioning a hole-making actuator. Compared with existing technologies, it has the following advantages: (1) The positioning method and device of the hole-making actuator, by setting a clamping mechanism, can achieve soft contact and reduce processing vibration. The floating pressure head can adaptively clamp different types and curvatures of surfaces. It automatically compensates for the small positional deviation between the pressure head and the workpiece. When the pressure head encounters situations such as incomplete hole alignment or inconsistent workpiece tolerances during the pressing process, the automatic floating pressure head can achieve horizontal fine adjustment without manual intervention, ensuring smooth pressing and greatly improving the product qualification rate. In addition, the pressure head has a flexible cylindrical hole structure with three-level vibration damping effect. The cylindrical hole structure gradually decreases from large to small, accurately fitting the surface for hole making.

[0015] (2) The hole-making actuator positioning method and device, by setting up a drilling mechanism and adopting an independent feeding mode, mainly includes a servo motor, a linear module, an electric spindle, a drill bit, a spring collet and other devices. The servo motor is driven by a fixed amount through a program to drive the linear module to drive a certain amount. The electric spindle is fixed on the linear module to drive the hole making. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention.

[0017] Figure 2 This is a schematic diagram showing the relationship between the various coordinate systems of the robot hole-making system of the present invention.

[0018] In the diagram: 1. Clamping mechanism; 2. Drilling mechanism; 101. First-level vibration damping; 102. Third-level vibration damping; 103. Second-level vibration damping; 201. Linear module; 202. Electric spindle; 203. Spring collet; 204. Drill bit; 205. Servo motor. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1-2 This invention provides a technical solution: a positioning method for a hole-making actuator, including a coordinate system for a robot hole-making system, specifically comprising the following steps: S1. Based on robot reachability and equipment interference analysis, the hole-making area is divided into several sub-regions using offline programming software; S2. Establish the robot tool coordinate system; S3. Establish the robot's base coordinate system by dividing the region using the four-point method; S4. Calibrate the reference point and obtain its error; S5. Import the hole position information file and reference point error into the offline programming software, input the processing parameters to generate the hole making program, and download it to the robot.

[0021] The more specific steps of the above-mentioned hole-making actuator positioning method are as follows: S1. Based on robot reachability and equipment interference analysis, the hole-making area is divided into several sub-regions using offline programming software; S2. Establish the robot tool coordinate system, extract the wall panel hole information and generate simulation coordinate points through offline programming software, perform motion simulation and path planning based on the robot workspace and equipment layout, and divide the hole-making area. Use the motion platform to move the robot body to make the target area in the optimal workspace. Finally, the industrial robot accurately positions the end effector through joint coordinated movement to complete the auxiliary operations required for drilling, such as tool rotation, feeding and clamping, and chip removal.

[0022] The coordinate system of the robot hole-making system includes the robot flange coordinate system, robot tool coordinate system, robot coordinate system, assembly site coordinate system, sub-area coordinate system, aircraft coordinate system, and measurement position coordinate system; S3. Establish the robot's base coordinate system by dividing the region using the four-point method. Calculate the transformation relationship between the measured position of the target point in the measurement coordinate system and its theoretical value in the assembly site coordinate system using the SVD least squares matching algorithm. This ensures that all measured values ​​in the measurement coordinate system are uniformly transformed to the assembly site coordinate system. The steps for constructing the assembly site coordinate system are as follows: A1. Determine the coordinate axis direction: Take the direction of the robot guide rail as the X-axis direction; determine the Y and Z axes by fitting straight lines through the robot's movement along its own Y and Z axes respectively. A2. Verification of orthogonality: The calculated angle between the X-axis and the Y-axis is 90.02°, indicating good orthogonality; A3. Establish the origin and direction of the coordinate system: Select a common observation point as the origin, and use the three-point calibration method to establish the coordinate system at the assembly site; A4. Obtain initial reference values ​​for observation points: Measure typical common observation points (such as TW1-4, TE1-4, DN1-2, DS1-2) in the measurement position coordinate system, and obtain their coordinate values ​​in the assembly site coordinate system through coordinate transformation, which are used as initial theoretical values.

[0023] The robotic hole-making test platform is a fixed system, and its panel model installation and hole-to-be-made information are both based on a fixed aircraft coordinate system. To obtain the pose transformation matrix between the aircraft coordinate system and the assembly site coordinate system, calibration is performed using pre-made holes in the panel: the measured coordinates of the pre-made hole points Pi (i=1,2,3...) are measured based on the assembly site coordinate system, and the theoretical coordinates P'i (i=1,2,3...) in the aircraft coordinate system are extracted from the digital model. The homogeneous transformation matrix between the two coordinate systems is then calculated using the singular value decomposition (SVD) matching algorithm. The pose matrix of the aircraft coordinate system in the assembly site coordinate system for: surface: Homogeneous transformation matrix representation

[0024] Table: The Euler angles of the aircraft coordinate system in the assembly site coordinate system are as follows

[0025] Establishment of robot tool coordinate system and regional coordinate system Due to the robot's reach limitation, site planning and area division are necessary before drilling. The large skin area is divided into multiple sub-regions to ensure the robot can cover the drilling range of each region from a single station, without tooling interference and with the guide rails fixed. The specific division is determined by importing the product, tooling, and robot models into simulation software, and establishing a corresponding sub-region coordinate system for each region. Based on the established tool coordinate system, aircraft coordinate system, and assembly site coordinate system, the pose relationship between the aircraft coordinate system and the robot base coordinate system is established using the four-point method, measured in the aircraft coordinate system. This allows the robot to determine the coordinates of the hole position in the robot coordinate system, thereby guiding the end effector to precise positioning. Each sub-region requires an independent establishment of the aircraft coordinate system and robot coordinate system relationship. However, the same end effector only requires one robot tool coordinate system.

[0026] The steps to set it up are as follows: B1. Based on the on-site measurement requirements for the aircraft drilling area, locate and fix the measuring equipment, establish a robot flange coordinate system, and guide it to move linearly along the x, y, and z axes and rotate around each axis within the coordinate system; use the accompanying software to perform line-to-circle fitting, and finally establish the homogeneous transformation matrix of the robot flange coordinate system relative to the measurement position coordinate system {Laser} based on the measurement data. .

[0027] Table: Homogeneous transformation matrix of robot flange coordinate system in measurement position

[0028] B2. Using measurement software, fit the center of the tool end face as the origin of the robot tool coordinate system, and with the feed direction as its z-axis, establish a homogeneous transformation matrix of the robot tool coordinate system relative to the measurement position coordinate system {Laser} based on the measurement data. As shown in the table below: Table: Homogeneous transformation matrix of robot flange coordinate system in measurement position

[0029] B3, by Find the position of Tool under Tool0 and input the robot hole-making actuator.

[0030] Table: Homogeneous transformation matrix of robot tool coordinate system in robot flange coordinate system

[0031] B4. After uniformly converting the measurement results to the aircraft coordinate system, move the robot to the target position according to the station information planned by the simulation software, and establish the pose relationship between the aircraft coordinate system and the robot coordinate system using the four-point method, that is, complete the calibration of the sub-region coordinate system. .

[0032] B5. Move the robot along the guide rail. The direction vector V of the laser measurement platform guide rail in the aircraft coordinate system is... Obtain the orientation vector of the platform guide rail in the robot coordinate system. This allows us to obtain the coordinate system of a sub-region at any position on the guide rail based on a known sub-region coordinate system.

[0033] The above-mentioned hole-making actuator positioning method is implemented through the following structure: It includes a clamping mechanism 1 and a drilling mechanism 2. The clamping mechanism 1 is installed on the left side of the drilling mechanism 2. The drilling mechanism 2 includes a linear module 201. An electric spindle 202 is installed on the upper part of the linear module 201. A spring collet 203 is installed on the left side of the electric spindle 202.

[0034] A drill bit 204 is mounted on the left end of the spring collet 203, and a servo motor 205 is mounted on the right side of the linear module 201.

[0035] The clamping mechanism 1 includes a primary damping mechanism 101, a secondary damping mechanism 103 is installed on the left side of the primary damping mechanism 101, and a tertiary damping mechanism 102 is installed on the left side of the secondary damping mechanism 103.

[0036] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

Claims

1. A method for positioning a hole-making actuator, comprising a coordinate system for a robot hole-making system, characterized in that: Specifically, the following steps are included: S1. Based on robot reachability and equipment interference analysis, the hole-making area is divided into several sub-regions using offline programming software; S2. Establish the robot tool coordinate system; S3. Establish the robot's base coordinate system by dividing the region using the four-point method; S4. Calibrate the reference point and obtain its error; S5. Import the hole position information file and reference point error into the offline programming software, input the processing parameters to generate the hole making program, and download it to the robot.

2. The hole-making actuator positioning method according to claim 1, characterized in that: In step S2, a robot tool coordinate system is established, and the wall panel hole information is extracted and simulation coordinate points are generated using offline programming software. Based on the robot's workspace and equipment layout, motion simulation and path planning are performed to divide the drilling area. The robot body is moved using a motion platform to place the target area in the optimal workspace. Finally, the industrial robot precisely positions the end effector through joint coordinated movement to complete the tool rotation, feeding, clamping, and chip removal auxiliary operations required for drilling.

3. The positioning method for a hole-making actuator according to claim 1, characterized in that: The coordinate system of the robot hole-making system includes the robot flange coordinate system, the robot tool coordinate system, the robot coordinate system, the assembly site coordinate system, the sub-region coordinate system, the aircraft coordinate system, and the measurement position coordinate system.

4. The hole-making actuator positioning method according to claim 3, characterized in that: The conversion method between the measurement position coordinate system and the assembly site coordinate system is to calculate the conversion relationship between the actual position of the target point in the measurement position coordinate system and its theoretical value in the assembly site coordinate system using the SVD least squares matching algorithm, thereby uniformly converting all the measured values ​​in the measurement position coordinate system to the assembly site coordinate system.

5. The hole-making actuator positioning method according to claim 4, characterized in that: The steps for constructing the coordinate system at the assembly site are as follows: A1. Determine the coordinate axis direction: Take the direction of the robot guide rail as the X-axis direction; determine the Y and Z axes by fitting straight lines through the robot's movement along its own Y and Z axes respectively. A2. Verify orthogonality: The calculated angle between the X-axis and Y-axis is 90.02°; A3. Establish the origin and direction of the coordinate system: Select a common observation point as the origin, and use the three-point calibration method to establish the coordinate system at the assembly site; A4. Obtain the initial reference value of the observation point: Measure the typical common observation point in the measurement position coordinate system, and obtain its coordinate value in the assembly site coordinate system through coordinate transformation, which is used as the initial theoretical value.

6. A positioning device for a hole-making actuator, comprising a clamping mechanism (1) and a drilling mechanism (2), characterized in that: The clamping mechanism (1) is installed on the left side of the drilling mechanism (2). The drilling mechanism (2) includes a linear module (201). An electric spindle (202) is installed on the upper part of the linear module (201). A spring collet (203) is installed on the left side of the electric spindle (202).

7. A positioning device for a hole-making actuator according to claim 6, characterized in that: A drill bit (204) is mounted on the left end of the spring collet (203), and a servo motor (205) is mounted on the right side of the linear module (201).

8. A positioning device for a hole-making actuator according to claim 6, characterized in that: The clamping mechanism (1) includes a first-level damping (101), and a second-level damping (103) is installed on the left side of the first-level damping (101), and a third-level damping (102) is installed on the left side of the second-level damping (103).

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