Intelligent robot posture correction device and method

Abstract

The present invention relates to the field of robot technology, and in particular to an intelligent robot posture correction device and method thereof. The intelligent robot posture correction device includes a three-dimensional mobile platform, an intelligent robot, a correction plate, a laser sensor, a welding gun and an optical system, wherein the intelligent robot is arranged on the three-dimensional mobile platform, and the execution end is connected to the correction plate; the welding gun, the laser sensor and the optical system are arranged on the correction plate, the optical system is used to reflect the light emitted by the laser sensor onto the correction plate and to redirect the reflected light of the correction plate to be received by the laser sensor, and the laser sensor is used to detect the welding point position of the welding gun and obtain and output the reflection point position information reflected by the optical system. The present invention uses the switch of the optical system to enable the laser sensor to realize the two functions of precise positioning and real-time deviation correction, effectively reducing the posture error of the terminal assembly caused by cable dragging during the movement of the robot.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, and in particular to an intelligent robot posture correction device and method thereof. Background Art

[0002] At present, more and more industries are experiencing a gradual transition from traditional manual work to automation and intelligence. Robots are a revolutionary advancement in production automation, and robot intelligence is the main development trend at present. Corrugated sheet is a sheet with a three-dimensional or spatial structure. This structure enhances resistance to horizontal and vertical loads, and is widely used in the container industry due to its structural characteristics. Due to the influence of the processing accuracy and stability of the front-end stamping station, when the corrugated sheet is welded to the bottom beam, there is a problem of incoming material consistency, and automated welding cannot be achieved. At present, the industry generally adopts a special machine mode of PLC plus laser sensor, which has initially realized the automated welding of shallow corrugated sheets.

[0003] However, during the welding process, the existing robot cannot realize the uncertainty error of the terminal assembly posture caused by cable dragging during the movement. The uncertain change of the welding gun angle cannot realize the precise control of the welding line speed, thus limiting the realization of the welding automation of corrugated plate. Summary of the invention

[0004] In view of the above problems, the object of the present invention is to provide an intelligent robot posture correction device and method thereof, so as to reduce the posture error of the terminal assembly caused by cable dragging during the movement of the robot.

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

[0006] An intelligent robot posture correction device comprises a three-dimensional mobile platform, an intelligent robot, a correction plate, a laser sensor, a welding gun and an optical system, wherein the intelligent robot is arranged on the three-dimensional mobile platform, and the execution end is connected to the correction plate;

[0007] Welding gun, laser sensor and optical system setting correction board;

[0008] The optical system is used to reflect the emitted light of the laser sensor to the correction plate and to redirect the reflected light of the correction plate to be received by the laser sensor;

[0009] The laser sensor is used to detect the welding point position of the welding gun and obtain and output the reflection point position information reflected by the optical system.

[0010] The correction plate is provided with an anti-collision sensor, and the anti-collision sensor is provided with a connecting plate;

[0011] The welding gun, laser sensor and optical system are all arranged on the connecting plate, and the axis of the laser sensor is parallel to the axis of the anti-collision sensor; the axis of the welding gun and the axis of the laser sensor are arranged at an angle.

[0012] The optical system includes a correction cover, a correction cover opening and closing driving mechanism and a reflector assembly, wherein the correction cover is hinged on the connecting plate and is located at the front end of the laser sensor; the correction cover opening and closing driving mechanism is arranged on the connecting plate, and the output end is hinged to the correction cover; the correction cover opening and closing driving mechanism is used to drive the correction cover to rotate so that the correction cover is opened or closed relative to the laser sensor; the reflector assembly is arranged in the inner groove of the correction cover.

[0013] The reflector assembly includes a beam splitter, an auxiliary objective lens I and an auxiliary objective lens II, wherein the auxiliary objective lens I and the auxiliary objective lens II are respectively arranged at the upper and lower ends of the inner groove of the correction cover plate, and the beam splitter is arranged between the auxiliary objective lens I and the auxiliary objective lens II.

[0014] The beam splitter is arranged at an angle of 45° to the horizontal plane; the auxiliary objective lens I and the auxiliary objective lens II are arranged symmetrically, and the auxiliary objective lens II is parallel to the beam splitter.

[0015] The correction cover opening and closing driving mechanism comprises a cylinder, the tail of the cylinder is hinged to the connecting plate, and the output end of the cylinder is hinged to the correction cover.

[0016] The intelligent robot posture correction device also includes a control system; the intelligent robot and the three-dimensional mobile platform are both electrically connected to the control system.

[0017] The three-dimensional mobile platform includes an X-direction mobile mechanism, a Y-direction mobile mechanism and a Z-direction mobile mechanism connected in sequence, and the intelligent robot is connected to the output end of the Z-direction mobile mechanism;

[0018] The X-direction moving mechanism, the Y-direction moving mechanism and the Z-direction moving mechanism are all connected to the control system.

[0019] A method for performing posture correction by the above-mentioned intelligent robot posture correction device comprises the following steps:

[0020] 1) The correction cover is driven to rotate by the correction cover opening and closing driving mechanism, so that the correction cover is opened relative to the laser sensor, and the laser sensor detects the welding point position of the welding gun;

[0021] 2) driving the correction cover to rotate through the correction cover opening and closing driving mechanism so that the correction cover is closed relative to the laser sensor;

[0022] The light emitted by the laser sensor is reflected by the reflector assembly to the correction plate, and the reflected light of the correction plate is then redirected by the reflector assembly to be received by the laser sensor;

[0023] The laser sensor obtains the position change information of the reflection point and sends it to the control system;

[0024] The control system receives the position change information of the reflection point sent by the laser sensor, and controls the intelligent robot according to the position change information of the reflection point, thereby correcting the posture error of the welding gun in real time.

[0025] The light emitted by the laser sensor is deflected by the beam splitter and auxiliary objective lens I in turn and incident on the correction plate; the light reflected from the correction plate is incident on the auxiliary objective lens I, and is again deflected by the auxiliary objective lens I to the auxiliary objective lens II, reflected by the auxiliary objective lens II to form receiving light, and is received by the laser sensor 29.

[0026] The advantages and beneficial effects of the present invention are:

[0027] The present invention only installs one laser sensor, and by correcting the switch of the cover plate, the laser sensor can realize two functions of precise positioning and real-time deviation correction, effectively reducing the posture error of the terminal assembly caused by cable dragging during the movement of the robot.

[0028] The invention improves the quality of the welding process, especially the working condition of uncertain disturbance of external cables; the invention is applicable to related similar robot application industries, such as flame cutting, plasma cutting, laser welding, etc., to improve the accuracy of the process implementation. In flame cutting, the process is thermally deformed and the flame cutting accuracy is improved.

[0029] The anti-collision sensor of the present invention can prevent the welding gun from collision and deformation during the welding process, and can serve as a redundant safety backup for the anti-collision sensor. In the event that the anti-collision sensor fails, it can also prevent collision and deformation during the welding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is one of the axonometric diagrams of an intelligent robot posture correction device of the present invention;

[0031] Figure 2 This is the second isometric diagram of an intelligent robot posture correction device of the present invention;

[0032] Figure 3 for Figure 2 The enlarged image at point I in the middle;

[0033] Figure 4 The present invention is a schematic diagram of the working principle of an intelligent robot posture correction device.

[0034] In the figure: 1 is a slide, 2 is a slide rail, 3 is an X-axis gear rack mechanism, 4 is a slide motor, 5 is an electrical control cabinet, 6 is a transfer bracket, 7 is a robot control cabinet, 8 is a robot teaching box, 9 is a control upper cabinet, 10 is a slide drag chain, 11 is a META control cabinet, 12 is a welding wire barrel, 13 is a welding machine, 14 is a cantilever column, 15 is a cantilever beam, 16 is a Y-axis motor, 17 is a Z-axis external axis, 18 is a Z-axis rail, 19 is a Z-axis motor, 20 is a Y-axis moving slide plate, 21 is a Y-axis rail, 22 is a wire feeder machine, 23 is a cable bracket, 24 is a cable, 25 is an intelligent robot, 26 is a correction plate, 27 is an anti-collision sensor, 28 is a reflected light path, 29 is a laser sensor, 30 is a welding gun, 31 is a correction cover plate, 32 is a cylinder, 33 is a cylinder connecting hole, 34 is a correction cover plate connecting hole II, 35 is a correction cover plate connecting hole I, 36 is an auxiliary objective lens II, 37 is a reflected light turning light path, 38 is a spectroscope, 39 is a turning light path, 40 is an auxiliary objective lens I, 41 is an emitted light, 42 is a received light, and 43 is a connecting plate. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] like Figure 1-2 As shown, an intelligent robot posture correction device provided by the present invention includes a three-dimensional mobile platform, an intelligent robot 25, a correction plate 26, a laser sensor 29, a welding gun 30 and an optical system, wherein the intelligent robot 25 is arranged on the three-dimensional mobile platform, and the execution end is connected to the correction plate 26; the welding gun 30, the laser sensor 29 and the optical system are arranged on the correction plate 26, the optical system is used to reflect the emitted light of the laser sensor 29 onto the correction plate 26 and to redirect the reflected light of the correction plate 26 to be received by the laser sensor 29, and the laser sensor 29 is used to detect the welding point position of the welding gun 30 and obtain and output the reflection point position information reflected by the optical system.

[0037] like Figure 1 As shown, in the embodiment of the present invention, the three-dimensional mobile platform includes an X-direction moving mechanism, a Y-direction moving mechanism and a Z-direction moving mechanism connected in sequence, and the intelligent robot 25 is connected to the output end of the Z-direction moving mechanism.

[0038] Specifically, the X-direction moving mechanism includes a slide 1, a slide rail 2, an X-direction rack-and-pinion mechanism 3, a slide motor 4, and a transfer bracket 6, wherein the rack-and-pinion mechanism 3 includes a gear and a rack, the rack and the slide rail 2 are arranged on the slide 1 along the X direction, and the transfer bracket 6 is slidably connected to the slide rail 2 through a slider. The slide motor 4 is arranged on the transfer bracket 6, the gear is arranged on the output shaft of the slide motor 4 and meshes with the rack, the slide motor 4 drives the gear to rotate, and because the gear is meshed with the rack, the gear rolls on the rack, thereby driving the transfer bracket 6 to move along the slide rail 2.

[0039] Further, the slide 1 is provided with a drag chain groove, the slide drag chain 10 is placed in the drag chain groove, and one end of the slide drag chain 10 is fixedly connected to one side of the transfer bracket 6. The transfer bracket 6 is also provided with a welding machine 13 and a welding wire barrel 12, and the welding wire barrel 12 is placed in the welding wire barrel support frame of the transfer bracket 6.

[0040] The Y-axis moving mechanism includes a cantilever column 14, a cantilever beam 15, a Y-axis motor 16, a Y-axis moving slide plate 20 and a Y-axis guide rail 21, wherein the cantilever column 14 is arranged on the transfer bracket 6, the cantilever beam 15 is arranged on the top of the cantilever column 14, the Y-axis guide rail 21 is arranged on the cantilever beam 15, and the Y-axis moving slide plate 20 is slidably connected to the Y-axis guide rail 21 through a slider. The Y-axis motor 16 is arranged on the Y-axis moving slide plate 20 and is connected to the cantilever beam 15 through a Y-axis gear rack mechanism, and the Y-axis motor 16 drives the Y-axis moving slide plate 20 to move along the Y-axis guide rail 21 through the Y-axis gear rack mechanism.

[0041] The Z-axis moving mechanism includes a Z-axis external shaft 17, a Z-axis guide rail 18, a Z-axis gear rack mechanism and a Z-axis motor 19, wherein the Z-axis external shaft 17 is slidably connected with the Y-axis moving slide plate 20 through the Z-axis guide rail 18, and the Z-axis motor 19 is arranged on the Z-axis external shaft 17, and the output end is connected with the Y-axis moving slide plate 20 through the Z-axis gear rack mechanism. The Z-axis motor 19 drives the Z-axis external shaft 17 to move in the vertical direction through the Z-axis gear rack mechanism.

[0042] The intelligent robot 25 is installed at the lower end of the Z-direction external shaft 17. The intelligent robot 25 is a six-degree-of-freedom robot that can perform nine-axis coupled motion.

[0043] like Figure 3-4As shown, on the basis of the above embodiment, an anti-collision sensor 27 is provided on the correction plate 26, and a connecting plate 43 is provided on the anti-collision sensor 27. Specifically, the bottom of the anti-collision sensor 27 is connected to the correction plate 26, and the top is connected to the connecting plate 43. The welding gun 30, the laser sensor 29 and the optical system are all arranged on the connecting plate 43, and the axis of the laser sensor 29 is parallel to the axis of the anti-collision sensor 27. The welding gun 30 is arranged on the top of the connecting plate 43 and the axis is arranged at an angle with the axis of the laser sensor 29. The anti-collision sensor 27 can prevent the welding gun 30 from collision and deformation during the welding process.

[0044] Further, the welding gun 30 is connected to the wire feeder 22 via a cable 24, and the wire feeder 22 is arranged on the Z-direction external shaft 17. A cable bracket 23 is arranged on the Z-direction external shaft 17, and the cable 24 is supported by the cable bracket 23.

[0045] like Figure 4 As shown, in an embodiment of the present invention, the optical system includes a correction cover 31, a correction cover opening and closing driving mechanism and a reflector assembly, wherein the upper end of the correction cover 31 is hinged on the connecting plate 43 through a hinge shaft inserted in the correction cover connecting hole Ⅰ35, and is located at the front end of the laser sensor 29, and the correction cover 31 can rotate around the axis of the hinge shaft; the correction cover opening and closing driving mechanism is arranged on the connecting plate 43, and the output end is hinged to the correction cover 31 through the correction cover connecting hole Ⅱ34, which is used to drive the correction cover 31 to rotate, so that the correction cover 31 is opened or closed relative to the laser sensor 29; the reflector assembly is arranged in the inner groove of the correction cover 31.

[0046] In the embodiment of the present invention, the opening and closing driving mechanism of the correction cover plate includes a cylinder 32, which is arranged on one side of the connecting plate 43, and the rear end is hinged to the connecting plate 43 through the cylinder connecting hole 33, and the output end is hinged to the correction cover plate 31. The cylinder 32 drives the correction cover plate 31 to open and close the cover relative to the laser sensor 29.

[0047] like Figure 4 As shown, in the embodiment of the present invention, the reflector assembly includes a beam splitter 38, an auxiliary objective lens I 40 and an auxiliary objective lens II 36, wherein the auxiliary objective lens I 40 and the auxiliary objective lens II 36 are respectively arranged at the upper and lower ends of the inner groove of the correction cover 31, and the beam splitter 38 is arranged between the auxiliary objective lens I 40 and the auxiliary objective lens II 36. Further, the beam splitter 38 is arranged at an angle of 45° to the horizontal plane; the auxiliary objective lens I 40 and the auxiliary objective lens II 36 are symmetrically arranged, and the auxiliary objective lens II 36 is parallel to the beam splitter 38.

[0048] When the correction cover 31 is in the closed position, the light 41 emitted by the laser sensor 29 is incident on the beam splitter 38 and then the light path is turned to form the turned light path 39. The turned light path 39 is incident on the auxiliary objective lens I 40 and then the light path is turned to be projected onto the correction plate 26. The reflected light path 28 reflected from the correction plate 26 is then incident on the auxiliary objective lens I 40 to turn the light path to form the reflected light turned light path 37. The reflected light turned light path 37 passes through the beam splitter 38 and then is incident on the auxiliary objective lens II 36. The light path is turned again to form the received light 42. The received light 42 is received by the laser sensor 29. The beam splitter 38 plays the role of turning the light path on the one hand and filtering on the other hand. The auxiliary objective lens I 40 and the auxiliary objective lens II 36 play the role of turning the light path.

[0049] On the basis of the above embodiment, an intelligent robot posture correction device further includes a control system, which is arranged on the transfer bracket 6, and the intelligent robot 25, the X-direction moving mechanism, the Y-direction moving mechanism and the Z-direction moving mechanism are all connected to the control system. The control system receives the reflection point position change information sent by the laser sensor 29, and controls the intelligent robot 25 according to the reflection point position change information, so as to correct the posture error of the welding gun 30 in real time.

[0050] In the embodiment of the present invention, the control system includes an electrical control cabinet 5, a robot control cabinet 7, a robot teaching box 8, a control upper cabinet 9 and a META control cabinet 11. The bottom ends of the electrical control cabinet 5 and the robot control cabinet 7 are fixedly connected to the transfer bracket 6, the bottom end of the control upper cabinet 9 is fixedly connected to the upper surface of the robot control cabinet 7, the bottom end of the META control cabinet 11 is fixedly connected to the upper surface of the control upper cabinet 9, and the robot teaching box 8 is temporarily suspended on the outer surface of the robot control cabinet 7. The slide motor 4, the Y-axis motor 16 and the Z-axis motor 19 are connected to the electrical control cabinet 5; the intelligent robot 25 is connected to the robot control cabinet 7; the anti-collision sensor 27 and the laser sensor 29 communicate wirelessly with the META control cabinet 11.

[0051] The working process of an intelligent robot posture correction device provided by the present invention is as follows:

[0052] Step 1: The intelligent robot 25 performs nine-axis coupled motion and moves to a specified position.

[0053] Step 2: The cylinder 32 drives the correction cover plate 31 to open the cover, and the laser sensor 29 accurately locates and determines the position of the welding point.

[0054] Step 3: The cylinder 32 drives the correction cover plate 31 to close the cover, and the laser sensor 29 records the initial position of the reflection point in the Cartesian coordinate system.

[0055] Step 4: The intelligent robot 25 performs nine-axis coupled motion, and the laser sensor 29 provides feedback to the intelligent robot 25 through the position change of the reflection point in the Cartesian coordinate system, so as to correct the position of the welding gun 30 in real time.

[0056] On the basis of the above embodiment, the present invention further provides a method for posture correction using the intelligent robot posture correction device provided in the above embodiment, comprising the following steps:

[0057] 1) The correction cover 31 is driven to rotate by the correction cover opening and closing driving mechanism, so that the correction cover 31 is opened relative to the laser sensor 291, and the welding point position of the welding gun 30 is detected by the laser sensor 29;

[0058] 2) The correction cover 31 is driven to rotate by the correction cover opening and closing driving mechanism, so that the correction cover 31 is closed relative to the laser sensor 29; the light 41 emitted by the laser sensor 29 is reflected to the correction plate 26 by the reflector assembly, and the reflected light of the correction plate 26 is then redirected by the reflector assembly to be received by the laser sensor 29;

[0059] Specifically, the light 41 emitted by the laser sensor 29 is deflected by the beam splitter 38 and the auxiliary objective lens I 40 in turn and is incident on the correction plate 26; the light reflected from the correction plate 26 is incident on the auxiliary objective lens I 40, and is again deflected by the auxiliary objective lens I 40 to the auxiliary objective lens II 36, and is reflected by the auxiliary objective lens II 36 to form the receiving light 42, which is received by the laser sensor 29.

[0060] The laser sensor 29 obtains the position change information of the reflection point and sends it to the control system; the control system receives the position change information of the reflection point sent by the laser sensor 29, and controls the intelligent robot 25 according to the position change information of the reflection point, thereby correcting the posture error of the welding gun 30 in real time.

[0061] In the embodiment of the present invention, when the correction cover 31 is opened, the laser sensor 29 is used to accurately locate the position of the welding point. When the correction cover 31 is closed, on the one hand, it can protect the lens of the laser sensor 29; on the other hand, the laser sensor 29 establishes a Cartesian coordinate system with the axis of the correction plate 26 as the Y axis and the plane on one side of the correction plate 26 as the YZ plane, and feeds back the position change of the reflection point in the Cartesian coordinate system to the intelligent robot 25, and the intelligent robot 25 corrects the position of the welding gun 30 in real time, thereby reducing the error caused by the cable 24 dragging the welding gun 30 during the movement of the intelligent robot 25.

[0062] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. An intelligent robot posture correction device, characterized in that: It comprises a three-dimensional mobile platform, an intelligent robot (25), a correction plate (26), a laser sensor (29), a welding gun (30) and an optical system, wherein the intelligent robot (25) is arranged on the three-dimensional mobile platform, and the execution end is connected to the correction plate (26); The welding gun (30), the laser sensor (29) and the optical system are arranged on the correction plate (26); The optical system is used to reflect the emitted light of the laser sensor (29) onto the correction plate (26) and to redirect the reflected light of the correction plate (26) to be received by the laser sensor (29); The laser sensor (29) is used to detect the welding point position of the welding gun (30) and obtain and output the reflection point position information reflected by the optical system; An anti-collision sensor (27) is provided on the correction plate (26), and a connecting plate (43) is provided on the anti-collision sensor (27); The welding gun (30), the laser sensor (29) and the optical system are all arranged on the connecting plate (43), and the axis of the laser sensor (29) is parallel to the axis of the anti-collision sensor (27); the axis of the welding gun (30) and the axis of the laser sensor (29) are arranged at an angle; The optical system comprises a correction cover plate (31), a correction cover plate opening and closing drive mechanism, and a reflector assembly, wherein the correction cover plate (31) is hinged on the connecting plate (43) and is located at the front end of the laser sensor (29); The correction cover plate opening and closing driving mechanism is arranged on the connecting plate (43), and the output end is hinged to the correction cover plate (31); The correction cover opening and closing driving mechanism is used to drive the correction cover (31) to rotate, so that the correction cover (31) is opened or closed relative to the laser sensor (29); the reflector assembly is arranged in the inner groove of the correction cover (31); When the correction cover (31) is opened, the laser sensor (29) is used to accurately locate the position of the welding point; when the correction cover (31) is closed, the position of the welding gun (30) is corrected in real time by the intelligent robot (25); The reflector assembly comprises a beam splitter (38), an auxiliary objective lens I (40) and an auxiliary objective lens II (36); The correction cover plate opening and closing drive mechanism comprises a cylinder (32).

2. The intelligent robot posture correction device according to claim 1, characterized in that: The auxiliary objective lens I (40) and the auxiliary objective lens II (36) are respectively arranged at the upper and lower ends of the inner groove of the correction cover plate (31), and the beam splitter (38) is arranged between the auxiliary objective lens I (40) and the auxiliary objective lens II (36).

3. The intelligent robot posture correction device according to claim 2, characterized in that: The beam splitter (38) is arranged at an angle of 45° to the horizontal plane; the auxiliary objective lens I (40) and the auxiliary objective lens II (36) are arranged symmetrically, and the auxiliary objective lens II (36) is parallel to the beam splitter (38).

4. The intelligent robot posture correction device according to claim 1, characterized in that: The tail of the cylinder (32) is hinged to the connecting plate (43), and the output end is hinged to the correction cover plate (31).

5. The intelligent robot posture correction device according to any one of claims 2 to 4, characterized in that: It also includes a control system; the intelligent robot (25) and the three-dimensional mobile platform are both electrically connected to the control system.

6. The intelligent robot posture correction device according to claim 5, characterized in that: The three-dimensional mobile platform comprises an X-direction mobile mechanism, a Y-direction mobile mechanism and a Z-direction mobile mechanism which are connected in sequence, and the intelligent robot (25) is connected to the output end of the Z-direction mobile mechanism; The X-direction moving mechanism, the Y-direction moving mechanism and the Z-direction moving mechanism are all connected to the control system.

7. A method for posture correction using the intelligent robot posture correction device according to claim 6, characterized in that: It includes the following steps: 1) driving the correction cover (31) to rotate by means of a correction cover opening and closing driving mechanism, so that the correction cover (31) is opened relative to the laser sensor (29), and the laser sensor (29) detects the welding point position of the welding gun (30); 2) driving the correction cover (31) to rotate by means of the correction cover opening and closing driving mechanism, so that the correction cover (31) is closed relative to the laser sensor (29); The light (41) emitted by the laser sensor (29) is reflected by the reflector assembly to the correction plate (26), and the reflected light of the correction plate (26) is then redirected by the reflector assembly to be received by the laser sensor (29); The laser sensor (29) obtains the position change information of the reflection point and sends it to the control system; The control system receives the position change information of the reflection point sent by the laser sensor (29), and controls the intelligent robot (25) according to the position change information of the reflection point, thereby correcting the position error of the welding gun (30) in real time.

8. The method according to claim 7, characterized in that The light (41) emitted by the laser sensor (29) is deflected by the beam splitter (38) and the auxiliary objective lens I (40) in sequence and incident on the correction plate (26); The light reflected from the correction plate (26) is incident on the auxiliary objective lens I (40), and is again redirected to the auxiliary objective lens II (36) through the auxiliary objective lens I (40), and is reflected by the auxiliary objective lens II (36) to form receiving light (42), which is then received by the laser sensor (29).

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