CN-122007638-A - Robot laser ablation system and method for curved surface parts

CN122007638ACN 122007638 ACN122007638 ACN 122007638ACN-122007638-A

Abstract

The invention discloses a robot laser ablation system and a robot laser ablation method for curved surface parts, which belong to the technical field of laser processing and comprise a six-degree-of-freedom mechanical arm, a laser processing head, a connecting plate, a control console, a tool adjusting platform and a laser generator; the method for constructing the mechanical arm laser ablation device, acquiring the transformation matrix and carrying out laser ablation on the curved surface part can carry out high-efficiency laser ablation processing on the curved surface part, has the processing effect of quickly removing large allowance compared with the traditional cutting or grinding, has simpler part installation and positioning because the part is not required to be directly contacted during laser processing, can be used as a rough processing scheme for processing with high precision, can automatically convert a CAM program into a mechanical arm processing file by means of numerical control program conversion software, and reduces the programming difficulty of mechanical arm processing instructions.

Inventors

GUO JIURONG
ZHANG LIN
ZHU SHAOWEI
GAO XIN
SHI JIALIN
CHEN JIE
TAO ZHIYONG
QIN XIAOPIN
Ruan chao
GAO JINKUN

Assignees

成都飞机工业（集团）有限责任公司

Dates

Publication Date: 20260512
Application Date: 20260210

Claims (14)

1. A robot laser ablation system for curved surface parts is characterized by comprising a six-degree-of-freedom mechanical arm, a laser processing head, a connecting plate, a control console, a tool adjusting platform and a laser generator, wherein the laser generator is connected with the laser processing head, the control console is connected with the six-degree-of-freedom mechanical arm and the laser generator, the six-degree-of-freedom mechanical arm moves according to a specific track in the processing process, the laser processing head is arranged at an end effector of the six-degree-of-freedom mechanical arm through the connecting plate, the control console is used for automatically controlling the processing process, and the tool adjusting platform is used for adjusting the pose of the parts to be processed and tools thereof.
2. The laser ablation system of the robot for curved surface parts according to claim 1, wherein the control console comprises a mechanical arm control module and a laser control module, wherein the mechanical arm control module is used for calling and executing different mechanical arm control programs to ensure that a tool coordinate system moves along a specific track at a preset feeding speed, a machining program is generated after the machining program is programmed by CAM software, a laser machining head switch is controlled by instructions in the mechanical arm control program, and the laser control module is used for setting and adjusting relevant parameters of laser ablation.
3. The robotic laser ablation system of claim 1, further comprising a cooler for reducing the temperature of the laser processing head during use.
4. A robotic laser ablation method by a robotic laser ablation system for curved surface parts according to any of claims 1-3, comprising the steps of: Step one, determining laser ablation parameters; step two, programming a numerical control program; Step three, numerical control program conversion; Step four, verifying the track accuracy; and step five, laser processing.
5. The method for robot laser ablation of curved surface parts according to claim 4, wherein in the first step, the laser ablation parameters are determined by an ablation test, and the ablation parameters include a feeding speed of a mechanical arm, a shape and a size of an ablation area, a laser power, a spot scanning speed and a spot scanning line interval.
6. A robot laser ablation method for curved surface parts according to claim 5 is characterized in that an ablation test process comprises the steps of manually setting a starting point, an end point and a feeding speed of movement of a mechanical arm at a mechanical arm control module of a control console, setting the shape and the size of an ablation area, laser power, a light spot scanning speed and a light spot scanning line interval at the laser control module, starting the mechanical arm control module, moving the mechanical arm from the starting point to the end point along a straight line according to a given feeding speed, starting a laser processing head after starting to move, closing the laser processing head at the end point, repeatedly adjusting ablation parameters on the premise of not changing the starting point and the end point of movement of the mechanical arm, observing the ablation depth, the ablation uniformity and the ablation dust accumulation condition of hard and brittle materials after ablation, and selecting different ablation parameters according to processing requirements.
7. The method for robot laser ablation of curved surface parts according to claim 6, wherein in the second step, a tool model and a part model are built in CAM software, a workpiece coordinate system is built on the tool model, and theoretical values of distances between the workpiece coordinate system and edges of the tool are recorded as follows 、 And programming the tool path under the workpiece coordinate system, namely when the tool path needs to be processed in a layering mode, the interlayer distance is consistent with the ablation depth in the first step so as to ensure that the laser focus position is always on the surface of the area to be processed, and deriving the tool path file in an APT format after programming is completed.
8. A method of robot laser ablation of curved surface features that according to claim 7, the transformation relation between the object coordinate system and the base coordinate system is that if there is only translation transformation and no rotation transformation between the end effector coordinate system and the tool coordinate system, the transformation between the end effector coordinate system and the tool coordinate system is not performed The shafts being respectively translated And obtaining a tool coordinate system to obtain a transformation matrix: ; Since the six-degree-of-freedom mechanical arm is simplified into a six-degree-of-freedom link, the base is defined as link 0, and so on, the end effector is link 6, and the transformation matrix of the base coordinate system to the end effector coordinate system is obtained according to the modified DH method: ; Wherein: ; the meaning of the parameters in the matrix is as follows: a) Winding machine Rotation of the shaft Angle, make Shaft and method for producing the same The shafts are on the same plane; b) Winding machine Axial translation Make the following Shaft and method for producing the same The shafts are at the same height; c) Winding machine Rotation of the shaft Angle, make Shaft and method for producing the same The shafts are on the same straight line; d) Edge of the frame Distance of axis translation Make the connecting rod Origin of coordinate system of (c) and connecting rod Is coincident with the origin of the coordinate system; thus, a transformation matrix from the base coordinate system to the tool coordinate system Because the tool coordinate system varies with the machining process, it is assumed that Track points, each track point corresponding to the current tool coordinate system, then the first Transformation matrix of the individual tool coordinate system is And solving the corresponding joint position of the mechanical arm under the current gesture by a mechanical arm kinematics inverse solution algorithm.
9. A robot laser ablation method for curved surface parts according to claim 7, wherein the transformation relationship between the object coordinate system and the base coordinate system is the object coordinate system The plane is usually flush with the upper surface of the tool, and The axis is vertical upwards, in order to obtain translation transformation matrix The workpiece coordinate system is required to be firstly set Level is adjusted and the plane is adjusted Axis and base coordinate system The axes remain parallel.
10. The method for robot laser ablation of curved surface parts according to claim 9, wherein the adjustment method comprises adjusting the long side and the base coordinate system when the tool is placed The axes are approximately parallel, the dial indicator is mounted on the connecting plate by using the magnetic dial indicator frame, the dial indicator measuring head is adjusted to the tool plane, and the manual operation mechanical arms are respectively arranged along the axes Shaft and method for producing the same The shaft moves, the change of the dial indicator is observed, and the dial indicator is arranged along the edge 、 The maximum value and the minimum value in the shaft movement process are respectively 、、、 According to the numerical value difference of the dial indicator, adjusting a base screw of the tool adjusting platform, when meeting the following conditions And (2) and When the tool leveling platform is considered to be leveled, the workpiece coordinate system The plane being adjusted to be horizontal while recording the plane The value is Wherein, the method comprises the steps of, And in the same way, the dial indicator measuring head is adjusted to the surface of the long side of the tool, and the mechanical arm edge is manually operated The shaft moves, the rotation of the end effector coordinate axis is not generated in the process, when In this case, the object coordinate system can be considered 、 Axis and base coordinate system 、 The measuring head of the dial indicator is adjusted to be parallel to the laser focus, the mechanical arm is operated to enable the dial indicator to approach the tool from the long side and the short side of the tool respectively, rotation of the end effector coordinate axis is not generated in the process, when dial data suddenly changes from zero value, the laser focus position can be considered to contact the tool, and the position of the mechanical arm when contacting the long side and the short side is recorded respectively And ; Theoretically, the object coordinate system The distance between the shaft and the long side of the tool is , The distance between the shaft and the long side of the tool is Because the value recorded by the mechanical arm is the coordinate value of the center of the flange of the end effector in the world coordinate system, the coordinate of the origin of the coordinate system of the workpiece in the base coordinate system can be obtained through theoretical value calculation Translation transformation matrix whereby the base coordinate system is transformed to the object coordinate system: 。
11. A robot laser ablation method for curved surface parts according to claim 7 is characterized in that in the third step, the robot laser ablation method is automatically processed by a robot program conversion software, inverse T 3 -1 of a transformation matrix T 3 is obtained through coordinate conversion of a robot ablation system, tool track points in a CAM program under a workpiece coordinate system are converted into track points in a base coordinate system, transformation matrix T i of each track point can be obtained through position and swing angle values in an APT file, angles of joints of the robot are obtained through inverse solution of the transformation matrix T i , the angles are written into a robot processing file, and the robot is automatically driven to move according to the track points by the robot processing file.
12. The method of claim 11, further comprising adding an on laser command after each feed is completed and adding an off laser command before the withdrawal is initiated.
13. A robot laser ablation method of curved surface parts according to claim 12 is characterized in that in the fourth step, before ablation processing is started, the accuracy of positions of a mechanical arm and a laser processing head is verified, the verification method is that four light inspection holes with the aperture of 1mm and the depth of 1mm are arranged on a tool, under the condition that a console only starts red light indication, a mechanical arm verification program is started, the mechanical arm sequentially reaches the four light inspection holes along a straight line, if the positions of the mechanical arm and the laser processing head are accurate and a transformation matrix is accurate, red light indication light spots can completely coincide with the light inspection holes after reaching the light inspection holes, otherwise, the mechanical arm or the laser processing head needs to be debugged again and the transformation matrix is checked.
14. The method for robot laser ablation of curved surface parts according to claim 13, wherein in step five, the cooler, the laser generator and the console are sequentially turned on, the converted machining file of the mechanical arm is imported into the console, and the machining program is started by the console.

Description

Robot laser ablation system and method for curved surface parts Technical Field The invention belongs to the technical field of laser processing, and particularly relates to a robot laser ablation system and a robot laser ablation method for curved surface parts. Background Laser ablation can greatly improve the material removal efficiency when processing hard and brittle materials, but is more complex in the processing process than planar parts because of the complex structure of curved parts and higher requirements on the degree of freedom of processing. The common laser curved surface ablation generally adopts a mode of extracting a polygon surface patch to obtain a normal vector to enable a laser spot to be perpendicular to the surface of a curved surface part, the accuracy of the method depends on the size of the surface patch, but the calculation is complex, especially when the complex curved surface is faced, the time cost consumed by the calculation complexity cannot meet the requirement of batch processing, and the surface patch needs to be extracted again when the complex curved surface is faced, so that the processing track has poor flexibility. The robot laser ablation method for the curved surface part is characterized in that a laser is mounted at an end effector of a mechanical arm, and the high-free characteristic of the robot is utilized to enable a laser spot to move along a specific track during curved surface part processing, so that the focal point of the laser spot is ensured to be on the surface of the curved surface part, and therefore efficient laser ablation processing of the curved surface part is achieved. The Chinese patent with publication number CN108555464A discloses a large-scale complex curved surface dynamic focusing laser processing method and system, which adopts a mode of splitting complex curved surfaces in a splitting-blocking-layering manner, and can realize dynamic focusing of complex curved surfaces, but has poor flexibility of the device and lower efficiency when processing thicker curved surface parts. The Chinese patent with publication number of CN208195762U discloses a laser heating auxiliary milling curved surface processing device, which can use a laser to locally heat a workpiece so as to improve the machinability of the workpiece, but cannot directly remove materials, lacks a calculation method between a laser head position parameter and a milling cutter position, and cannot accurately ensure that a laser spot is always on the surface of the workpiece. Disclosure of Invention In order to solve the problems in the prior art, the robot laser ablation system and the robot laser ablation method for the curved surface parts are provided, the robot laser ablation device is built, a transformation matrix is obtained, and the curved surface part laser ablation method is carried out, so that the curved surface parts can be subjected to efficient laser ablation processing, compared with the traditional cutting or grinding, the robot laser ablation system and the robot laser ablation method have the processing effect of rapidly removing large allowance, and are simpler in part installation and positioning because the parts do not need to be directly contacted during laser processing, and the method can be used as a rough processing scheme, and CAM programs can be automatically converted into mechanical arm processing files by means of numerical control program conversion software, so that the processing instruction programming difficulty of the mechanical arms is reduced. The invention is realized by the following technical scheme: The robot laser ablation system for the curved surface parts comprises a six-degree-of-freedom mechanical arm, a laser processing head, a connecting plate, a control console, a tool adjusting platform and a laser generator, wherein the laser generator is connected with the laser processing head, the control console is connected with the six-degree-of-freedom mechanical arm and the laser generator, the six-degree-of-freedom mechanical arm moves according to a specific track in the processing process, the laser processing head is arranged at an end effector of the six-degree-of-freedom mechanical arm through the connecting plate, the control console is used for automatically controlling the processing process, and the tool adjusting platform is used for adjusting the pose of the parts to be processed and tools of the parts. Preferably, the control console comprises a mechanical arm control module and a laser control module, wherein the mechanical arm control module is used for calling and executing different mechanical arm control programs to ensure that a tool coordinate system moves along a specific track at a preset feeding speed, a machining program is generated after the machining program is programmed by CAM software, a laser machining head switch is controlled by instructions in the mechanical arm control program, and the laser contro