A laser cutting auxiliary device for intelligent robots

Abstract

This invention discloses a laser cutting auxiliary device for intelligent robots, relating to the field of robotic arm technology. Addressing the problems of background technologies, such as the inability to actively identify and compensate for transient errors in real time, limited ability to attenuate high-frequency disturbances, or difficulty in effectively suppressing end-effector vibrations above several hundred hertz due to the large inertia and servo bandwidth limitations of the robot body, the present invention proposes the following solution: a connecting base and a laser head are connected to the outer wall of the intelligent robot's wrist via a flange. The bottom of the connecting base is provided with a stator spherical shell, which includes an upper stator shell bolted to the lower outer wall of the connecting base and a lower stator shell bolted to the bottom outer wall of the upper stator shell. This invention can actively identify vibrations and compensate for transient errors in real time, while effectively suppressing end-effector vibrations above several hundred hertz, improving the quality and yield of three-dimensional laser cutting.

Description

Technical Field

[0001] This invention relates to the field of robotic arm technology, and in particular to a laser cutting auxiliary device for intelligent robots. Background Technology

[0002] A robotic arm is an automated operating device that can mimic certain movements and functions of a human hand and arm to grasp, move objects, or operate tools according to a fixed program. Its characteristic is that it can complete various expected tasks through programming. In terms of structure and performance, it combines the advantages of both humans and machines. Multi-joint robotic arms have the advantages of flexible movement, low motion inertia, and strong versatility. They can grasp workpieces close to the base and can work around obstacles between the body and the working machine.

[0003] When performing high-precision laser cutting, intelligent robots need to move precisely along a preset trajectory while maintaining a constant posture and focal length of the laser head relative to the workpiece surface. However, during high-speed movement, the robot body will generate high-frequency chatter at the micron to sub-millimeter level at the end due to factors such as reducer backlash, linkage inertia, servo jitter, and external environmental vibration. This chatter is directly transmitted to the laser head, causing the beam focus to drift irregularly on the workpiece surface, resulting in uneven kerf width, slag buildup, incomplete cutting in some areas, or even burning out optical components, which seriously restricts the quality and yield of 3D laser cutting.

[0004] To suppress such vibrations, existing solutions mostly adopt passive methods, such as adding spring dampers or rubber vibration damping pads between the robot wrist and the laser head. Such structures cannot actively identify and compensate for transient errors in real time, have limited ability to attenuate high-frequency disturbances, and introduce hysteresis and nonlinear deformation, which reduces trajectory accuracy. Other solutions attempt to compensate from the control end, but due to the large inertia of the robot body and the limitation of servo bandwidth, it is difficult to effectively suppress end-effector vibrations above several hundred hertz. Summary of the Invention

[0005] This invention provides a laser cutting auxiliary device for intelligent robots, which solves the problems in the prior art where intelligent robots cannot actively identify and compensate for transient errors in real time, have limited ability to attenuate high-frequency disturbances, or are limited by the large inertia and servo bandwidth of the robot body, making it difficult to effectively suppress end vibrations above several hundred hertz.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A laser cutting auxiliary device for an intelligent robot includes a connecting base and a laser head connected to the outer wall of the robot's wrist via a flange. The connecting base has a stator spherical shell at its bottom. The stator spherical shell includes an upper stator shell bolted to the lower outer wall of the connecting base and a lower stator shell bolted to the bottom outer wall of the upper stator shell. Both the upper and lower stator shells have several countersunk holes on their spherical inner walls, and electromagnets are inserted into each of these holes. One end of each electromagnet faces the center of the stator spherical shell. Several Hall sensor modules are located within the upper and lower stator shells, with each Hall sensor positioned between adjacent electromagnets. A moving sphere is located within the stator spherical shell, with a uniform air gap between the moving sphere and the stator spherical shell. The upper and lower halves of the moving sphere are each provided with permanent magnet blocks on their outer walls. One end of each of the permanent magnets faces the center of the stator shell, and one end of each permanent magnet faces one end of each of the electromagnets. The middle outer wall of the moving sphere is provided with a number of miniature permanent magnet calibration blocks. The stator shell is provided with a heat dissipation module. The heat dissipation module includes a heat dissipation shell sleeved on the outside of the stator shell, a number of current drivers respectively bonded to the inner wall of the heat dissipation shell, and a number of heat-conducting plates respectively welded to the inner wall of the heat dissipation shell. The number of current drivers are respectively connected to the coils of the electromagnets through wires. A miniature ranging sensor is provided at the bottom of the moving sphere. A microcontroller is provided below the connecting base, and the microcontroller is connected to the electromagnets and Hall sensor modules through signal lines.

[0007] Preferably, the outer wall of the connecting base has several positioning pin holes, and the outer wall at the center of the connecting base has a through hole for passing through the optical fiber and the auxiliary air tube. The lower outer wall of the connecting base has a connecting boss.

[0008] Preferably, the upper stator housing includes a cylindrical connecting ring and a hemispherical mounting shell welded to the lower outer wall of the connecting ring, and the connecting ring is bolted to the outer wall of the connecting boss, and an opening is provided on the bottom outer wall of the lower stator housing.

[0009] Preferably, each of the countersunk holes has a wire outlet hole on its inner wall, and each of the upper stator shell and the lower stator shell has a number of mounting grooves on their spherical inner walls, and each of the mounting grooves has a wiring hole. The Hall sensor module includes a flexible printed circuit board and a number of three-dimensional Hall sensors respectively soldered to the outer wall of the flexible printed circuit board, and the Hall sensor module is encapsulated in the mounting groove with epoxy resin.

[0010] Preferably, channels are opened on the top and bottom outer walls of the moving sphere, and several mounting holes are opened on the upper and lower outer walls of the moving sphere, and several permanent magnet blocks are respectively embedded in the mounting holes. The several permanent magnet blocks are radially magnetized. Several fixing holes are opened on the middle outer wall of the moving sphere, and several miniature permanent magnet calibration blocks are respectively embedded in the fixing holes.

[0011] Preferably, a laser head mounting cylinder is welded to the outer wall of the bottom of the moving sphere, and the laser head is screwed into the laser head mounting cylinder. The optical fiber and air tube of the laser head pass through the laser head mounting cylinder into the inner cavity of the moving sphere and are connected upward through the connecting ring of the upper stator shell and the through hole on the connecting base to the laser on the intelligent robot.

[0012] Preferably, the heat dissipation sphere is composed of two hemispherical heat dissipation shells welded together, and the top of the heat dissipation sphere is fixed to the upper outer wall of the stator sphere, and the bottom of the heat dissipation sphere is fixed with an annular dustproof net, which is also fixed to the lower outer wall of the stator sphere.

[0013] Preferably, a lower mounting base is welded to the lower outer wall of the laser head mounting cylinder, and the miniature ranging sensor is connected to the outer wall of one side of the lower mounting base by bolts.

[0014] Preferably, an upper mounting base is welded to the outer wall of the connecting ring at the upper part of the upper stator housing, and the microcontroller is bolted to the outer wall of one side of the upper mounting base.

[0015] The beneficial effects of this invention are as follows: The moving sphere is completely suspended within the stator shell by a micron-level air gap, with no mechanical contact with the stator. The microcontroller actively controls the attitude of the moving sphere through electromagnets, compensating for robot end-effector vibrations in real time. Multiple sets of electromagnets distributed in the upper and lower stator shells can apply forces to the permanent magnets in the upper and lower halves of the moving sphere in a coordinated manner, generating a pure couple and radial force around the center of the sphere. This independently controls pitch, roll, yaw, and altitude fine-tuning, fully compensating for errors in all six degrees of freedom. This ensures the absolute stability of the laser head's attitude and distance relative to the workpiece, actively identifies vibrations and compensates for transient errors in real time, and effectively suppresses end-effector vibrations above several hundred hertz, improving the quality and yield of 3D laser cutting. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall main structure of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0017] Figure 2 This is a schematic diagram of the overall top view of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0018] Figure 3This is a schematic cross-sectional view of the overall structure of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0019] Figure 4 This is a schematic diagram of the cross-sectional structure of the stator spherical shell of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0020] Figure 5 This is a bottom view of the stator spherical shell of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0021] Figure 6 This is a schematic diagram of the cross-sectional structure of the moving sphere of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0022] Figure 7 This is a schematic cross-sectional view of the heat dissipation module of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0023] Figure 8 This is a bottom view of the heat dissipation module of a laser cutting auxiliary device for intelligent robots proposed in this invention.

[0024] Figure 9 The present invention proposes Figure 2 Enlarged structural diagram at point A in the middle.

[0025] Figure 10 The present invention proposes Figure 3 Enlarged structural diagram at point B.

[0026] In the diagram: 1. Connecting base; 2. Stator spherical shell; 201. Upper stator shell; 202. Lower stator shell; 3. Electromagnet; 4. Hall sensor module; 5. Moving ball; 6. Permanent magnet block; 7. Miniature permanent magnet calibration block; 8. Laser head mounting cylinder; 9. Laser head; 10. Heat dissipation module; 101. Heat dissipation spherical shell; 102. Current driver; 103. Heat conduction plate; 104. Dustproof net; 11. Lower mounting base; 12. Miniature ranging sensor; 13. Upper mounting base; 14. Microcontroller. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0028] Example 1, referring to Figure 1-3A laser cutting auxiliary device for intelligent robots includes a connecting base 1, a stator spherical shell 2, an electromagnet 3, a Hall sensor module 4, a moving sphere 5, a permanent magnet block 6, a miniature permanent magnet calibration block 7, a laser head mounting cylinder 8, a laser head 9, a heat dissipation module 10, a miniature ranging sensor 12, and a microcontroller 14. The connecting base 1 is flange-shaped, and the upper end face of the connecting base 1 is provided with a positioning pin hole corresponding to the wrist of the intelligent robot. A through hole is opened in the center for optical fiber and auxiliary air tube to pass through. A connecting boss is provided at the lower part of the connecting base 1.

[0029] The stator spherical shell 2 is assembled from the upper stator shell 201 and the lower stator shell 202 by bolts. The upper part of the upper stator shell 201 is a cylindrical connecting ring, which is fixed to the connecting boss of the connecting base 1 by bolts. The lower part is a hemispherical mounting shell. The lower stator shell 202 is a hemispherical structure with a circular opening at the bottom for the laser head mounting cylinder 8 to pass through and swing.

[0030] On the inner spherical surfaces of the upper stator shell 201 and the lower stator shell 202, multiple countersunk holes are opened at different latitudes. The countersunk holes are cylindrical blind holes, and their axes all point to the center of the stator shell. Several electromagnets 3 are inserted into several countersunk holes, with one end of the electromagnet 3 facing the center of the shell. The curvature of the end face of the electromagnet 3 is consistent with the inner spherical surface of the stator shell 2, and they are installed flush. Each countersunk hole has a wire outlet hole at the bottom for leading out the coil wire of the electromagnet 3.

[0031] On the inner spherical surface of the stator sphere 5, there are mounting slots along the meridian between adjacent electromagnets 3. The Hall sensor module 4 consists of a flexible printed circuit board and multiple three-dimensional Hall sensors soldered onto the flexible printed circuit board. It is embedded in the mounting slot, potted with epoxy resin and ground until it is smooth and flush with the inner spherical surface. There are cable routing holes on the back of the mounting slot, so that the FPC signal lines can be led out from the outer wall of the stator and finally connected to the microcontroller 14. The Hall sensor module 4 is used to detect the magnetic field generated by the miniature permanent magnet calibration block 7 on the mover sphere and calculate the real-time position and attitude of the mover.

[0032] The mover sphere 5 is a hollow spherical shell made of non-magnetic material, located inside the stator sphere shell 2. The air gaps between the mover sphere 5 and the inner spherical surface of the stator are uniform. Mounting holes are formed on the upper and lower outer walls of the mover sphere 5, and permanent magnet blocks 6 are embedded in these holes. Each permanent magnet block 6 is radially magnetized, with one end facing the center of the stator sphere shell 2 and the other end facing away from the center and directly opposite the end face of the corresponding electromagnet 3. A miniature permanent magnet calibration block 7 is embedded in the fixing hole on the outer wall of the middle part of the mover sphere 5, serving as the magnetic field source for posture detection. Channels are formed at the top and bottom of the mover sphere 5 for optical fibers and air tubes to pass through.

[0033] The laser head mounting cylinder 8 is welded to the bottom outer wall of the moving ball 5. The laser head 9 is fixed inside the cylinder by threads. The optical fiber and air tube of the laser head 9 enter the inner cavity of the moving ball shell 2 through the mounting cylinder, pass upward through the channel, the connecting ring of the upper stator shell 201 and the through hole of the connecting base 1, and finally connect to the laser on the intelligent robot.

[0034] A lower mounting base 11 is welded to the lower outer wall of the laser head mounting cylinder 8. A miniature distance sensor 12 is fixed to the lower mounting base 11 by bolts. It is used to detect the distance from the laser head nozzle to the workpiece surface in real time and feed the signal back to the microcontroller 14.

[0035] The heat dissipation module 10 includes a heat dissipation spherical shell 101, a current driver 102, and a heat-conducting plate 103. The heat dissipation spherical shell 101 is formed by welding two hemispherical heat dissipation shells together and is fitted onto the outside of the stator spherical shell 2. The top is fixed to the upper part of the stator spherical shell 2, and an annular dustproof mesh 104 is installed between the bottom and the stator spherical shell 2. The current driver 102 is bonded to the inner wall of the heat dissipation spherical shell 101 and is connected to the coils of each electromagnet 3 through wires. The heat-conducting plate 103 is welded to the inner wall of the heat dissipation spherical shell 101 to enhance the conduction of heat from the current driver 102 to the upper part of the stator spherical shell 2. External air enters the annular space between the heat dissipation spherical shell 101 and the stator spherical shell 2 from the bottom dustproof mesh 104, rises after being heated, and is discharged from the top gap to form natural convection cooling.

[0036] An upper mounting base 13 is welded to the outer wall of the connecting ring on the upper part of the upper stator housing 201. The microcontroller 14 is fixed to the upper mounting base 13 by bolts. The microcontroller 14 communicates with the robot's main controller through the bus, receives the target pose program instructions, and dynamically calculates and outputs the control current of each electromagnet 3 based on the real-time pose of the mover fed back by the Hall sensor module 4 and the distance signal of the micro ranging sensor 12, driving the mover ball 5 to levitate and perform attitude and height compensation.

[0037] During robot operation, the controller converts the preset cutting trajectory into the target pose and height of the moving ball and sends it to the microcontroller 14 in real time. The microcontroller 14 obtains the six-dimensional pose feedback of the moving ball through the Hall sensor module 4, runs a multivariable decoupling control algorithm, and independently adjusts the current magnitude and polarity of each electromagnet 3 through the current driver 102. The electromagnets 3 distributed in the upper stator shell 201 and the lower stator shell 202 generate a synergistic magnetic force on the permanent magnets 6 in the upper and lower halves of the moving ball, synthesizing a couple and radial force around an arbitrary axis at the center of the ball, so that the moving ball 5 can make frictionless pitch, roll, yaw and height fine adjustment, and compensate for the vibration error of the robot end in real time. The miniature ranging sensor 12 provides a precise height signal to ensure that the laser focus is always at the optimal position on the workpiece surface and to ensure the cutting quality.

[0038] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A laser cutting auxiliary device for an intelligent robot, comprising a connecting base (1) and a laser head (9) connected to the outer wall of the wrist of an intelligent robot via a flange, characterized in that, The bottom of the connecting base (1) is provided with a stator spherical shell (2), which includes an upper stator shell (201) connected to the lower outer wall of the connecting base (1) by bolts and a lower stator shell (202) connected to the bottom outer wall of the upper stator shell (201) by bolts. The upper stator shell (201) and the lower stator shell (202) each have several countersunk holes on their spherical inner walls, and each countersunk hole has an electromagnet (3) inserted into it. One end of each electromagnet (3) faces the center of the stator shell (2). The upper stator shell (201) and the lower stator shell (202) each have several Hall sensor modules (4), and each Hall sensor (4) is located between two adjacent electromagnets (3). The stator spherical shell (2) is provided with a moving sphere (5), and there is a uniform air gap between the moving sphere (5) and the stator spherical shell (2). The upper and lower half of the moving sphere (5) are provided with permanent magnet blocks (6). One end of several permanent magnets (6) faces the center of the stator spherical shell (2), and one end of several permanent magnets (6) faces one end of several electromagnets (3). Several miniature permanent magnet calibration blocks (7) are provided on the middle outer wall of the moving sphere (5). The stator spherical shell (2) is provided with a heat dissipation module (10) on the outside. The heat dissipation module (10) includes a heat dissipation spherical shell (101) sleeved on the outside of the stator spherical shell (2), a number of current drivers (102) respectively bonded to the inner wall of the heat dissipation spherical shell (101), and a number of heat-conducting plates (103) respectively welded to the inner wall of the heat dissipation spherical shell (101). The number of current drivers (102) are respectively connected to the coils of a number of electromagnets (3) through wires. The lower part of the moving ball (5) is provided with a miniature ranging sensor (12), and the lower part of the connecting base (1) is provided with a microcontroller (13), and the microcontroller (13) is connected to several electromagnets (3) and several Hall sensor modules (4) through signal lines.

2. The laser cutting auxiliary device for intelligent robots according to claim 1, characterized in that, The outer wall of the connecting base (1) has several positioning pin holes, and the outer wall at the center of the connecting base (1) has a through hole for passing through optical fiber and auxiliary air tube. The lower outer wall of the connecting base (1) has a connecting boss.

3. The laser cutting auxiliary device for intelligent robots according to claim 2, characterized in that, The upper stator shell (201) includes a cylindrical connecting ring and a hemispherical mounting shell welded to the lower outer wall of the connecting ring. The connecting ring is bolted to the outer wall of the connecting boss. The lower stator shell (202) has an opening on the bottom outer wall.

4. The laser cutting auxiliary device for intelligent robots according to claim 1, characterized in that, A number of countersunk holes are provided with wire outlet holes on their inner walls. A number of mounting slots are provided on the inner walls of the spherical surfaces of the upper stator shell (201) and the lower stator shell (202), and a number of wiring holes are provided in the mounting slots. The Hall sensor module (4) includes a flexible printed circuit board and a number of three-dimensional Hall sensors respectively soldered to the outer wall of the flexible printed circuit board. The Hall sensor module (4) is encapsulated in the mounting slots with epoxy resin.

5. The laser cutting auxiliary device for intelligent robots according to claim 1, characterized in that, The moving ball (5) has channels on its top and bottom outer walls. The upper and lower half of the moving ball (5) has several mounting holes on its outer walls. Several permanent magnet blocks (6) are respectively embedded in the mounting holes. The several permanent magnet blocks (6) are radially magnetized. The middle outer wall of the moving ball (5) has several fixing holes. Several micro permanent magnet calibration blocks (7) are respectively embedded in the fixing holes.

6. The laser cutting auxiliary device for intelligent robots according to claim 3, characterized in that, A laser head mounting cylinder (8) is welded to the bottom outer wall of the moving ball (5), and the laser head (9) is screwed into the laser head mounting cylinder (8). The optical fiber and air tube of the laser head (9) pass through the laser head mounting cylinder (8) into the inner cavity of the moving ball (5) and are connected to the laser on the intelligent robot through the connecting ring of the upper stator shell (2) and the through hole on the connecting base (1).

7. The laser cutting auxiliary device for intelligent robots according to claim 1, characterized in that, The heat dissipation spherical shell (101) is made of two hemispherical heat dissipation shells welded together, and the top of the heat dissipation spherical shell (101) is fixed on the upper outer wall of the stator spherical shell (2). The bottom of the heat dissipation spherical shell (101) is fixed with an annular dustproof net (104), and the dustproof net (104) is fixed on the lower outer wall of the stator spherical shell (2).

8. The laser cutting auxiliary device for intelligent robots according to claim 6, characterized in that, The lower mounting base (11) is welded to the outer wall of the lower part of the laser head mounting cylinder (8), and the miniature ranging sensor (12) is connected to the outer wall of the lower mounting base (11) by bolts.

9. A laser cutting auxiliary device for intelligent robots according to claim 3, characterized in that, An upper mounting base (13) is welded to the outer wall of the connecting ring on the upper part of the upper stator housing (201), and the microcontroller (14) is connected to the outer wall of one side of the upper mounting base (13) by bolts.

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