Method and device for guiding and directionally stripping coating layer of high-voltage cable based on directional derivative

Abstract

The invention discloses a method and a device for directionally stripping a coating layer of a high-voltage cable based on directional derivative guidance, and the method and the device are used for stripping the coating layer of the cable, and the stripping comprises the following steps: constructing a space coordinate system which takes a conductor center of a to-be-stripped end face of the high-voltage cable as a coordinate origin and takes a cutting point of a cutter as a moving point; obtaining the minimum thickness and the maximum thickness of the cylindrical area of the to-be-stripped section of the high-voltage cable and the initial point cloud data of the cylindrical curved surface; setting a stripping length and a taper, acquiring spatial point position information serving as a cutter entering point at the top end surface of the cylindrical curved surface, and acquiring spatial point position information serving as a cutter lifting point at the distance from the top end surface of the cylindrical curved surface; and cutting in from any point on the top end surface of the cylindrical curved surface as a cutter feeding point, and moving to a cutter lifting point for dynamic machining. According to the invention, the problem that the conical chamfer of the high-voltage cable is inconvenient to process can be solved, the stripped conical surface area is neat and smooth in transition, and the quality problems of steps, pits, canine tooth edges, burrs and the like are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of high-voltage cable processing, and in particular to a method and a device for directional stripping of a high-voltage cable coating based on directional derivative guidance. Background Art

[0002] With the continuous improvement of my country's power infrastructure, power distribution artery projects such as "West-to-East Power Transmission" and "South-to-North Power Transmission" often require high-voltage or even ultra-high-voltage, large-capacity power transmission and transformation components to undertake ultra-long-distance transmission of electric energy. Among them, high-voltage cable joints are the core components of cable lines in power transmission and transformation components. They bear the heavy responsibility of electrical connection between cables and between cables and other equipment, ensuring the safe transmission of electric energy, which is directly related to the safe and stable operation of power stations. If a high-voltage cable is damaged during service, it is necessary to remake the cable joint on site for connection. It is required to directional strip the insulating shielding layer of the cable coating and strip the cable end into a conical chamfer similar to a pencil head to facilitate docking and adjustment in the joint. Faced with the complex interlayer composition of the high-voltage cable coating, uneven distribution of processing allowances, and poor cable rigidity, the cable has problems such as bending. In the process of directional stripping of the cable end coating, there are pain points such as uneven coating processing allowances and model uncertainty caused by bending deformation, which has brought great troubles to power maintenance. Summary of the invention

[0003] In order to solve the current technical problems, the main purpose of the present invention is to provide a method and device for directional stripping of high-voltage cable sheath based on directional derivative guidance, so as to solve the problem of inconvenience in processing conical chamfers of high-voltage cables.

[0004] In order to overcome the problems existing in the prior art, the technical solution adopted by the present invention is: a method for directional stripping of a high-voltage cable coating based on directional derivative guidance, which is used to strip the coating of the cable, and the stripping process includes: S1. Construct a spatial coordinate system with the conductor center of the end face to be stripped of the high-voltage cable as the coordinate origin and the cutting point of the tool as the moving point; S2, obtaining the minimum thickness r, the maximum thickness R of the processing allowance of the cylindrical area of ​​the high-voltage cable to be stripped, and the initial point cloud data of the cylindrical surface; S3, setting the stripping length L and the pencil cone chamfer angle θ, obtaining the spatial point position information of the top end surface of the cylindrical surface as the entry point, and obtaining the spatial point position information of the cylindrical surface at a distance L from the top end surface as the lift point; S4, the single-pass tool path trajectory is to cut in from any point on the top end face of the cylindrical surface as the entry point, move along the generatrix direction of the surface to the lift point for processing, and after the single-pass tool path trajectory is processed, move along the circumferential feed amount of the cylindrical surface by ∆d, and then repeat the single-pass tool path trajectory until the processing is completed; during the processing, the coordinates of the entry point on the cutting plane relative to the coordinate origin are changed from the maximum thickness R and the minimum thickness r of the coating layer processing allowance until the coordinates of the two points finally coincide, and the coordinates of the lift point relative to the entry point are or Dynamically change the independent variable; align the tool with the cylindrical surface normal.

[0005] In S1, the end of the high-voltage cable to be stripped is fixed, and a three-dimensional measurement camera is fixedly placed at a distance H from the end face of the high-voltage cable to construct a coordinate system with the axis of the conductor of the end face of the high-voltage cable to be stripped as the coordinate origin P. 0 (0,0,0), the cutting point of the machining tool is the spatial coordinate system of the moving point.

[0006] In S2, a line laser scanning device is used with the coordinate origin as the center. The line laser scanning device emits an array line laser parallel to the cylindrical surface busbar of the high-voltage cable, rotates around the circumference of the high-voltage cable, and scans the cylindrical surface area to be stripped on the surface of the high-voltage cable. Combined with the three-dimensional measurement camera at the end face, the minimum thickness r, maximum thickness R of the cylindrical surface area to be stripped of the high-voltage cable and the initial point cloud data of the cylindrical surface area are collected and calibrated.

[0007] In S3, the tool is brought close to the top of the cylindrical surface, and any entry point on the top is used as the initial moving point on the cylindrical surface. Combined with the change of the initial point cloud data relative to the cylindrical surface, the spatial point information of the entry point is calculated and marked as P 1 (x 1 ,y 1 , z).

[0008] In S3, the top of the cylindrical surface is used as the entry point, and the length L is moved along the generatrix direction of the cylindrical surface. Combined with the change of the initial point cloud data relative to the cylindrical surface, the spatial point information of the lift point is calculated and marked as P. 2 (x 2 ,y 2 , zL).

[0009] In S4, when stripping, the tool starts from any point on the cylindrical surface near the end surface as the entry point P 1 Cut in, and in the process of stripping the end of the high-voltage cable to be stripped into a cone angle, the cutting point P 1 The point gradually moves towards the coordinate origin P 0 Close to the cutting point P 1 With the coordinate origin P 0 Coincident; with the coordinate origin P 0The axis of the cylindrical surface, the single-path tool path is any point on the top end of the cylindrical surface as the tool entry point P 1 Cut in, along the direction of the surface generatrix to the tool lift point P 2 Mobile processing, after processing a single-pass tool path, move along the cylindrical surface with a circumferential feed amount of ∆d, and then repeat the single-pass tool path until the stripping process is completed; during the processing, the entry point P on the cutting plane 1 Relative coordinate origin P 0 The coordinates of the coating layer are variable from the maximum thickness R and the minimum thickness r of the coating layer until the coordinates of the two points coincide. 1 Point and P 2 The tangent plane where the point is located gradually moves from perpendicular to the x0y plane to an angle of (90°-θ) with the x0y plane. The coordinates of the tool lift point relative to the tool entry point are or Dynamically change the independent variable.

[0010] The entry point P on the cylindrical surface 1 Point coordinates (x 1 ,y 1 , z) determines P 2 Point coordinates (x 2 ,y 2 , zL), so based on P 1 Point and P 2 Point constructs a binary function Z = f (x 1 ,y 1 ), where the differential of the above binary function is P 1 Point and P 2 The tangent plane on which the point lies; Cutting point P on the cutting plane 1 To the knife lifting point P 2 The directional derivative of the maximum value is: ; Cutting point P on the cutting plane 1 To the knife lifting point P 2 The directional derivative of the minimum is: ; Where: Represents the entry point P of the binary function at the maximum thickness R of the machining allowance 1 Point (x 1 ,y 1 , z 1 )’s directional derivative; Represents the entry point P of the binary function at the minimum thickness r of the machining allowance 1 Point (x 1 ,y 1 , z 1)’s directional derivative; Indicates that when the machining allowance is at its maximum thickness R, the cutting plane P 1 Click to P 2 The distance of the points; Indicates the minimum thickness r of the machining allowance on the cutting plane P 1 Click to P 2 The distance of the point.

[0011] After S4, the steps of stripping quality inspection are also included: After the processing is completed, the pencil cone area after the insulation shielding layer is stripped is manually checked. If quality problems such as steps, pits, canine edges and burrs are found, steps S2 and S3 need to be repeated, and the tool is replaced with a smaller model, and the circumferential step distance ∆d is reduced simultaneously. Then, the stripping process is repeated according to step S4 until the quality of the cone area after the insulation shielding layer is stripped meets the requirements.

[0012] A device for directional stripping of a high-voltage cable sheath based on directional derivative guidance, used to implement the method for directional stripping of a high-voltage cable sheath based on directional derivative guidance, the device comprising an annular frame, a clamping and locking device, a motion mechanism, a laser scanning device, a slide assembly and an electric spindle, the annular frame is equipped with at least two clamping and locking devices for clamping the high-voltage cable, one end of the annular frame is equipped with a motion mechanism, the motion mechanism can rotate along the annular frame, the motion mechanism is equipped with a laser scanning device and a slide assembly, the slide assembly is equipped with an electric spindle, and the rotating shaft of the electric spindle is used to install a tool; It also includes a three-dimensional measuring camera and a controller. The laser scanning device, the slide assembly, the electric spindle and the three-dimensional measuring camera are respectively connected to the controller for communication.

[0013] The slide assembly includes an X-axis slide, a Z-axis slide, a lifting seat, a rotating seat and a servo motor. The X-axis slide is installed on the motion mechanism, the Z-axis slide is installed on the sliding seat of the X-axis slide, the lifting seat is installed on the sliding seat of the Z-axis slide, a rotating shaft is fixedly connected to the lower end of the rotating seat, the rotating shaft passes through the lifting seat, and the rotating shaft is rotatably connected to the lifting seat, the electric spindle is installed on the rotating seat, the servo motor is installed on the lifting seat, and the output shaft of the servo motor is drivingly connected to the rotating shaft of the rotating seat.

[0014] The present invention has the following beneficial effects: 1. The method of the present invention can be used to measure the P on the cutting plane in real time. 1 Point and P 2The change of the coordinate data of the point is used to judge the change of the machining allowance of the current high-voltage cable coating, that is, the directional derivative of the cutting plane changes with the change of the machining allowance. The gradient vector and direction vector of the real-time cutting point P on the cutting plane are obtained by combining the directional derivative analysis. The feed amount of the stripping tool cutting point on the cylindrical curved surface coating of the high-voltage cable is adjusted in real time according to the pencil cone chamfer angle θ to ensure that the pencil cone angle of the stripping process and the pencil cone surface area are neat and smoothly transitioned without steps, pits, canine edges, burrs and other quality problems.

[0015] 2. The method of the present invention realizes high-quality preprocessing of the high-voltage cable sheath based on the integrated measurement and processing scheme guided by directional derivatives in a confined space, thereby solving the problem of surface geometric accessibility constraints caused by the stripping of the coating of an irregular cylindrical curved surface into a pencil cone due to factors such as flexural deformation and uneven distribution of the coating processing allowance when the cable is repaired and remade into joints in high-voltage and large-capacity power transmission and transformation components.

[0016] 3. The ring frame in the device of the present invention is used to install the clamping locking device and the motion mechanism. The clamping locking device is used to clamp the high-voltage cable. The motion mechanism is used to load the slide assembly and the electric spindle to rotate around the circumference of the ring frame. The slide assembly loads the electric spindle to drive the electric spindle to rise, fall, retract and swing. The tool is installed on the rotating shaft of the electric spindle to process the high-voltage cable. The laser scanning device and the three-dimensional measurement camera are used to obtain the conductor of the top end face axis of the high-voltage cable to be stripped as the coordinate origin P. 0 , and the cylindrical surface area S to be peeled 1 The method of the present application can solve the problem of inconvenience in processing conical chamfers of high-voltage cables. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the device of the present invention.

[0019] Figure 2 It is a schematic diagram of the top view of the structure of the device of the present invention.

[0020] Figure 3 A schematic cross-sectional view of a high voltage cable.

[0021] Figure 4 It is a structural schematic diagram of the slide assembly of the present invention.

[0022] Figure 5 It is a schematic diagram of the principle of the method of the present invention for guiding the orientation of a moving point on a cutting plane to change with machining allowance based on directional derivatives.

[0023] Reference numerals: An annular frame 10, a first annular frame 11, a second annular frame 12, and a connecting rod 13; Clamp locking device 20, telescopic device 21, clamp block 22; Motion mechanism 30, motion seat 31, drive motor 32; Laser scanning device 40; Slide assembly 50, X-axis slide 51, Z-axis slide 52, lifting seat 53, rotating seat 54, servo motor 55; Electric spindle 60, tool 61; 3D measurement camera 70; Controller 80; High voltage cable 1, conductor 2, coating 3. DETAILED DESCRIPTION

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0025] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0026] Secondly, the "present embodiment" or "embodiment" referred to herein refers to specific features, structures or characteristics that may be included in at least one implementation of the present invention.

[0027] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0028] Embodiment 1: See also Figures 1 to 5 This embodiment provides a method for directional stripping of a high-voltage cable coating based on a directional derivative, which is used to strip the coating of the cable. The stripping steps include: S1. Construct a spatial coordinate system with the conductor center of the end face to be stripped of the high-voltage cable as the coordinate origin and the cutting point of the tool as the moving point; S2, obtaining the minimum thickness r, the maximum thickness R and the initial point cloud data of the cylindrical surface of the cylindrical area of ​​the high-voltage cable to be stripped; S3, setting the stripping length L and the pencil cone chamfer angle θ, obtaining the spatial point position information of the top end surface of the cylindrical surface as the entry point, and obtaining the spatial point position information of the cylindrical surface at a distance L from the top end surface as the lift point; S4, the single-pass tool path trajectory is to cut in from any point on the top end face of the cylindrical surface as the entry point, move along the generatrix direction of the surface to the lift point for processing, and after the single-pass tool path trajectory is processed, move along the circumferential feed amount of the cylindrical surface by ∆d, and then repeat the single-pass tool path trajectory until the processing is completed; during the processing, the coordinates of the entry point on the cutting plane relative to the coordinate origin are changed from the maximum thickness R and the minimum thickness r of the coating layer processing allowance until the coordinates of the two points finally coincide, and the coordinates of the lift point relative to the entry point are or Dynamically change the independent variable; align the tool with the cylindrical surface normal.

[0029] Specifically, firstly, a three-dimensional measurement camera 70 and an external target ball are used to construct a coordinate system with the conductor 2 at the axis of the top end surface of the high-voltage cable 1 to be stripped as the coordinate origin P. 0 (0,0,0) and the cutting point of the tool 61 on the coating layer 2 are the moving points in the spatial coordinate system; then the minimum thickness r, maximum thickness R of the coating layer 3 in the cylindrical surface area to be peeled and the initial point cloud data of the cylindrical surface area S1 are measured and collected; then, any point P1 (x1, y1, z) at the top of the cylindrical surface area is used as the entry point to start uniform linear motion along the axis of the cylindrical surface to the bottom P2 of the cylindrical surface, marked as P2 (x2, y2, zL), as the lifting point; finally, combined with the definition of the directional derivative, according to the setting of the pencil cone chamfer angle θ, the coordinate origin P is used as the starting point. 0 Point is the axis of the cylindrical surface, P 1 and P 2 The tangent plane moves around the cylindrical surface of the high-voltage cable with a circumferential step distance △d, P 1 The point gradually moves towards the coordinate origin P 0 In the process of approaching the points, the minimum thickness r, the maximum thickness R of the coating layer 3 and the cylindrical surface area S 1 The initial point cloud data is used as the reference, and the P on the cutting plane measured in real time is used during the stripping process. 1 Point and P 2The coordinate data of the point is used to determine the machining allowance of the current coating layer, and the directional derivative of the cutting plane changes with the machining allowance. The gradient vector and the directional vector of the cutting point on the current cutting plane are obtained by back-calculating the directional derivative, that is, the radial feed amount of the tool 61 on the cylindrical surface is adjusted in real time. Finally, the present invention realizes the directional stripping of the coating layer of the cylindrical surface of the high-voltage cable according to the set cone chamfer angle θ based on the directional derivative guidance of the stripping tool, which solves the pain point problem described in the background technology.

[0030] In S1, the end of the high-voltage cable to be stripped is fixed, and a three-dimensional measurement camera is fixedly placed at a distance H from the end face of the high-voltage cable to construct a coordinate system with the axis of the conductor of the end face of the high-voltage cable to be stripped as the coordinate origin P. 0 (0,0,0), the cutting point of the machining tool is the spatial coordinate system of the moving point.

[0031] For details, see Figure 1 , 3 , put the device on the horizontal and vertical sections of the high-voltage cable 1, and adjust the clamping and locking device 20 with the high-voltage cable 1 as the axis to prevent the cable from being further bent and deformed by the processing force during the stripping process to affect the stripping quality, and simultaneously align the tool 61 of the device with the outer cylindrical surface area S of the part to be stripped at the end of the high-voltage cable 1 1 After installation and debugging, a three-dimensional measuring camera 70 is placed at a distance H from the end face of the high-voltage cable 1 to be stripped using a laser rangefinder. The external target ball and the three-dimensional measuring camera 70 are used to construct a coordinate system with the conductor 2 at the axis of the top end face of the high-voltage cable 1 to be stripped as the coordinate origin P. 0 (0,0,0), a spatial coordinate system in which the cutting point of the tool 61 on the cladding layer 3 is a moving point.

[0032] In S2, a laser scanning device is used to rotate around the circumference of the high-voltage cable with the coordinate origin as the center. The laser scanning device emits an array line laser to scan the cylindrical surface area to be stripped on the surface of the high-voltage cable. Combined with the three-dimensional measurement camera, the minimum thickness r, maximum thickness R and initial point cloud data of the cylindrical surface area to be stripped of the high-voltage cable are collected and calibrated.

[0033] For details, see Figure 1 , 2 The motion mechanism 30 is equipped with a laser scanning device 40 and a slide assembly 50, which are located on one side of the outer cylindrical surface of the high-voltage cable 1. The laser scanning device 40 emits an array of linear lasers to scan the cylindrical surface area to be stripped on the outer surface of the high-voltage cable 1. At the same time, the motion mechanism 30 is equipped with a laser scanning device 40 to construct a coordinate origin P with the conductor 2 at the axis of the high-voltage cable 1. 0 The center moves multiple circles along the circumference, and the minimum thickness r, the maximum thickness R and the cylindrical surface area S of the columnar area to be stripped of the high-voltage cable 1 are measured and collected in combination with the three-dimensional measurement camera 70 and calibrated.1 The initial point cloud data is transmitted back to the controller 80 after all the data is collected.

[0034] In S3, the tool is brought close to the top of the cylindrical surface, and any entry point on the top is used as the initial moving point on the cylindrical surface. Combined with the change of the initial point cloud data relative to the cylindrical surface, the spatial point information of the entry point is calculated and marked as P 1 (x 1 ,y 1 , z 1 ).

[0035] Specifically, see Figure 1 The motion mechanism 30 carries the laser scanning device 40 and the slide assembly 50 to approach the cylindrical surface area S 1 The top of the cylindrical surface S is taken as any entry point on the top, that is, the starting point of a single tool path. 1 The initial moving point on the cylindrical surface is combined with the change of the initial point cloud data relative to the cylindrical surface to calculate the spatial point information of the entry point, which is marked as P 1 (x 1 ,y 1 , z).

[0036] In S3, the top of the cylindrical surface is used as the entry point, and the length L is moved along the axial direction of the cylindrical surface. Combined with the change of the initial point cloud data relative to the cylindrical surface, the spatial point information of the lifting point is calculated and marked as P. 2 (x 2 ,y 2 , zL).

[0037] Specifically, see Figure 1 The controller 80 controls the motion mechanism 30 and the slide assembly 50 to move the tool 61 from the top of the cylindrical surface P 1 Point 2 is used as the entry point and moves in a straight line at a uniform speed along the generatrix of the cylindrical surface to point P at the bottom of the cylindrical surface. 2 Point, marked as P 2 (x 2 ,y 2 , zL), as the tool lifting point, that is, the end point of the single tool path.

[0038] After the end, the tool 61 is lifted off the cylindrical surface, and then the slide assembly 50 moves in a circumferential stepping motion for a certain distance ∆d with the coordinate origin constructed by the conductor 2 of the high-voltage cable axis as the center, where ∆d represents the offset of the multi-path. This step is repeated until the trial cutting track of the tool 61 covers all the areas to be stripped of the high-voltage cable sheath, and the cylindrical surface area S is determined. 1 Processing can reach, In S4, when stripping, the tool starts from any point on the cylindrical surface near the end surface as the entry point P 1Cut in, and in the process of stripping the end of the high-voltage cable to be stripped into a cone angle, the cutting point P 1 The point gradually moves towards the coordinate origin P 0 Close to the cutting point P 1 With the coordinate origin P 0 Coincident; with the coordinate origin P 0 The axis of the cylindrical surface is the tool entry point P. 1 To the knife lifting point P 2 Make uniform linear motion along the generatrix of the cylindrical surface, and at the same time make circumferential motion around the cylindrical surface with a circumferential step distance △d, at the entry point P 1 Gradually towards the coordinate origin P 0 When close to overlap, P 1 Point and P 2 The tangent plane where the point is located gradually moves from perpendicular to the x0y plane to an angle of (90°-θ) with the x0y plane. The cutting point P on the tangent plane 1 Relative coordinate origin P 0 The coordinates of the coating layer are variable from the maximum thickness R and the minimum thickness r of the machining allowance until the coordinates of the two points coincide with each other. 2 Relative entry point P 1 The coordinates of or Dynamically change the independent variable.

[0039] Specifically, see Figure 5 , the controller 80 receives the data, sets the final cone chamfer angle θ to be obtained within the stripping length L in the controller 80, and starts the stripping process: The motion mechanism 30 and the slide assembly 50 are equipped with an electric spindle 60 and a tool 61, and any point on the end surface area near the top of the cylindrical surface is used as the entry point P. 1 During the cutting and final stripping process, P 1 The point should gradually approach the origin of the coordinate system until P 1 Point and coordinate origin P 0 Point coincidence, combined with the definition of directional derivative, with the origin of coordinates P 0 Point is the axis of the cylindrical surface, P 1 Click to P 2 The point moves along the generatrix of the cylindrical surface at a uniform speed and then moves around the cylindrical surface with a circumferential step distance ∆d. 1 When the points gradually approach and coincide with the origin of the coordinate system, P 1 Point and P 2 The tangent plane where the point is located gradually moves from perpendicular to the x0y plane to an angle of (90°-θ) with x0y. 1 Point relative coordinate origin P 0The coordinates of the points are variable from the maximum thickness R and the minimum thickness r of the coating layer machining allowance until the coordinates of the two points finally coincide. 2 Point relative to P 1 The tool path distance of the point is or Dynamically change the independent variable.

[0040] The entry point P on the cylindrical surface 1 Point coordinates (x 1 ,y 1 , z) determines P 2 Point coordinates (x 2 ,y 2 , zL), so based on P 1 Point and P 2 Point constructs a binary function Z = f (x 1 ,y 1 ), where the differential of the above binary function is P 1 Point and P 2 The tangent plane on which the point lies; Cutting point P on the cutting plane 1 To the knife lifting point P 2 The directional derivative of the maximum value is: ; Cutting point P on the cutting plane 1 To the knife lifting point P 2 The directional derivative of the minimum is: ; Where: Represents the entry point P of the binary function at the maximum thickness R of the machining allowance 1 Point (x 1 ,y 1 , z 1 )’s directional derivative; Represents the entry point P of the binary function at the minimum thickness r of the machining allowance 1 Point (x 1 ,y 1 , z 1 )’s directional derivative; Indicates that when the machining allowance is at its maximum thickness R, the cutting plane P 1 Click to P 2 The distance of the points; Indicates the minimum thickness r of the machining allowance on the cutting plane P 1 Click to P 2 The distance of the point.

[0041] In the process of stripping the cylindrical surface of the high-voltage cable 1 into a conical chamfer θ, due to the uneven distribution of the machining allowance of the cylindrical high-voltage cable coating layer and the poor rigidity of the cable, the cylindrical surface of the coating layer 3 of the high-voltage cable 1 is actually a cylindrical surface. 1 Point and P 2 The change of the direction vector on the tangent plane of the point is affected by the maximum thickness R and minimum thickness r of the coating layer machining allowance. 1 And lift the knife and click P 2 When the tangent plane moves around the cylindrical surface, the directional derivative of the tangent plane changes with the change of the machining allowance of the cladding layer. The directional derivative is the dot product of the gradient vector and the direction vector.

[0042] In the face of problems such as uneven distribution of machining allowances of the cylindrical high-voltage cable coating and bending due to poor cable rigidity, the controller 80 gradually peels off the coating of the cylindrical curved surface area of ​​the high-voltage cable with a length of L using parameters such as the circumferential stepping distance ∆d (multi-path offset) and the cone chamfer angle θ. The minimum thickness r, maximum thickness R of the coating of the cylindrical area and the cylindrical curved surface area S are measured. 1 The initial point cloud data is used as the reference, and the P on the cutting plane measured in real time is used during the stripping process. 1 Point and P 2 The coordinate data of the point is used to judge the machining allowance of the current coating layer, that is, the directional derivative of the cutting plane changes with the change of the machining allowance, and the gradient vector and direction vector of the real-time cutting point on the cutting plane are obtained by substituting the above-mentioned directional derivative for inverse calculation, that is, the feed amount of the tool 61 on the cylindrical surface is adjusted in real time until the insulating shielding layer coated on the high-voltage cable on the cylindrical surface is stripped off into a cone in the form of a pencil cone with the axial conductor at the top end face as the axial convex point and a chamfer of θ.

[0043] After S4, the steps of stripping quality inspection are also included: After the processing is completed, the pencil cone area after the insulation shielding layer is stripped is manually checked. If quality problems such as steps, pits, canine edges and burrs appear, it is necessary to repeat steps S2 and S3, and replace the tool 61 with a small model, and simultaneously reduce the circumferential step distance △d. Then, the stripping process is repeated according to step S4 until the quality of the cone area after the insulation shielding layer is stripped meets the requirements.

[0044] Embodiment 2: See also Figure 1 , 2, a device for directional stripping of a high-voltage cable sheath based on directional derivative guidance, used to implement the method for directional stripping of a high-voltage cable sheath based on directional derivative guidance, the device comprises an annular frame 10, a clamping and locking device 20, a motion mechanism 30, a laser scanning device 40, a slide assembly 50 and an electric spindle 60, the annular frame 10 is equipped with at least two clamping and locking devices 20 for clamping a high-voltage cable 1, a motion mechanism 30 is installed at one end of the annular frame 10, the motion mechanism 30 can rotate along the annular frame 10, a laser scanning device 40 and a slide assembly 50 are installed on the motion mechanism 30, an electric spindle 60 is installed on the slide assembly 50, and a tool 61 is installed on the rotating shaft of the electric spindle 60; It also includes a three-dimensional measurement camera 70 and a controller 80 . The laser scanning device 40 , the slide assembly 50 , the electric spindle 60 and the three-dimensional measurement camera 70 are respectively connected to the controller 80 for communication.

[0045] The annular frame 10 is used to install the clamping and locking device 20 and the motion mechanism 30. The clamping and locking device 20 is used to clamp the high-voltage cable 1. The motion mechanism 30 is used to load the slide assembly 50 and the electric spindle 60 to rotate around the circumference of the annular frame 10. The slide assembly 50 loads the electric spindle 60 to drive the electric spindle 60 to rise, fall, retract and swing. The tool 61 is installed on the rotating shaft of the electric spindle 60 to process the high-voltage cable 1. The laser scanning device 40 and the three-dimensional measurement camera 70 are used to obtain the conductor 2 of the axis of the top end face of the high-voltage cable 1 to be stripped as the coordinate origin P 0 , and the cylindrical surface area S to be peeled 1 .

[0046] In this embodiment, see Figure 1 The annular frame 10 includes a first ring frame 11 and a second ring frame 12, and the first ring frame 11 and the second ring frame 12 are connected by a connecting rod 13. A gear ring is arranged on the second ring frame 12. The motion mechanism 30 includes a motion seat 31 and a drive motor 32. The lower side of the motion seat 31 is rotatably provided with inner and outer guide wheels. The motion seat 31 is movably mounted on the second ring frame 12 through the guide wheels on both sides. The motion seat 31 is mounted with a drive motor 32. The output shaft of the drive motor 32 is mounted with a gear, and the gear is meshed with the gear ring on the second ring frame 12 for transmission. Preferably, the drive motor 32 adopts a servo motor. The gear is driven to rotate by the drive motor 32, thereby driving the motion seat 31 to rotate around the second ring frame 12. It should be noted that the clamping locking device 20 needs to avoid the motion space of the motion mechanism 30.

[0047] See also Figure 1The clamp locking device 20 is respectively installed on the first ring frame 11 and the second ring frame 12, wherein three clamp locking devices 20 are respectively installed on the first ring frame 11 and the second ring frame 12 in an annular and uniform manner. The clamp locking device 20 includes a telescopic device 21 and a clamp block 22. The telescopic device 21 can adopt an electric cylinder, which can be synchronously telescoped at a fixed length. The clamp block 22 is fixedly installed at the telescopic end of the telescopic device 21. In this embodiment, the clamp block 22 is an arc-shaped structure adapted to the outer wall of the high-voltage cable. The high-voltage cable clamp is locked by the clamp locking device 20 to prevent shaking during processing.

[0048] See also Figure 4 The slide assembly 50 includes an X-axis slide 51, a Z-axis slide 52, a lifting seat 53, a rotating seat 54 and a servo motor 55. The X-axis slide 51 is installed on the motion mechanism 30, the Z-axis slide 52 is installed on the sliding seat of the X-axis slide 51, the lifting seat 53 is installed on the sliding seat of the Z-axis slide 52, a rotating shaft is fixedly connected to the lower end of the rotating seat 54, the rotating shaft passes through the lifting seat 53, and the rotating shaft is rotatably connected to the lifting seat 53, the electric spindle 60 is installed on the rotating seat 54, the servo motor 55 is installed on the lifting seat 53, and the output shaft of the servo motor 55 is drivingly connected to the rotating shaft of the rotating seat 54.

[0049] The X-axis slide 51 is used to drive the Z-axis slide 52 to move back and forth along the X-axis direction, and the Z-axis slide 52 is used to drive the lifting seat 53 to move back and forth up and down along the Z-axis direction. The rotating seat 54 can be rotated by the drive of the servo motor 55, so as to adjust the angle between the tool 61 and the cylindrical surface so that the tool 61 and the cylindrical surface are always normally aligned.

[0050] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, without undue experimentation, the development effort will be a routine task of design, fabrication, and production.

[0051] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for directional stripping of a high-voltage cable sheath based on directional derivative guidance, characterized in that: It is used to strip the sheath of the cable. The stripping process includes: S1. Construct a spatial coordinate system with the conductor center of the end face of the high-voltage cable to be stripped as the coordinate origin and the cutting point of the tool as the moving point; S2, obtaining the minimum thickness r, the maximum thickness R of the processing allowance of the cylindrical area of ​​the high-voltage cable to be stripped, and the initial point cloud data of the cylindrical surface; S3, setting the stripping length L and the pencil cone chamfer angle θ, obtaining the spatial point position information of the top end surface of the cylindrical surface as the entry point, and obtaining the spatial point position information of the cylindrical surface at a distance L from the top end surface as the lift point; S4, the single-pass tool path trajectory is to cut in from any point on the top end face of the cylindrical surface as the entry point, move along the generatrix direction of the surface to the lift point for processing, and after the single-pass tool path trajectory is processed, move along the circumferential feed amount of the cylindrical surface by ∆d, and then repeat the single-pass tool path trajectory until the processing is completed; during the processing, the coordinates of the entry point on the cutting plane relative to the coordinate origin are changed from the maximum thickness R and the minimum thickness r of the coating layer processing allowance until the coordinates of the two points finally coincide, and the coordinates of the lift point relative to the entry point are or Dynamically change the independent variable; align the tool with the cylindrical surface normal.

2. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 is characterized in that: In S1, the end to be stripped of the high-voltage cable is fixed, and a three-dimensional measurement camera is fixedly placed at a distance H from the end field of view of the top end of the high-voltage cable to construct a spatial coordinate system with the axis of the conductor of the end surface to be stripped of the high-voltage cable as the coordinate origin P0 (0,0,0) and the cutting point of the machining tool as the moving point.

3. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 is characterized in that: In S2, a line laser scanning device is used with the coordinate origin as the center. The line laser scanning device emits an array line laser parallel to the cylindrical surface busbar of the high-voltage cable, rotates around the circumference of the high-voltage cable, and scans the cylindrical surface area to be stripped on the surface of the high-voltage cable. Combined with the three-dimensional measurement camera at the end face, the minimum thickness r, maximum thickness R of the cylindrical surface area to be stripped of the high-voltage cable and the initial point cloud data of the cylindrical surface area are collected and calibrated.

4. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 is characterized in that: In S3, the tool is brought close to the top of the cylindrical surface, and any entry point on the top is used as the initial moving point on the cylindrical surface. Combined with the change of the initial point cloud data relative to the cylindrical surface, the spatial point information of the entry point is calculated and marked as P1 (x1, y1, z).

5. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 is characterized in that: In S3, the top of the cylindrical surface is used as the entry point, and a length L is moved along the generatrix direction of the cylindrical surface. Combined with the changes in the initial point cloud data relative to the cylindrical surface, the spatial point information of the lifting point is calculated and marked as P2 (x2, y2, zL).

6. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 is characterized in that: In S4, during stripping, the tool cuts in from any point on the end surface area near the top of the cylindrical surface as the entry point P1, and in the process of stripping the end of the high-voltage cable to be stripped at a cone angle, the entry point P1 gradually approaches the coordinate origin P0 until the entry point P1 coincides with the coordinate origin P0; with the coordinate origin P0 as the axis of the cylindrical surface, the single-channel tool path trajectory is to cut in from any point on the top end surface of the cylindrical surface as the tool entry point P1, and move along the direction of the surface generatrix to the tool lift point P2 for processing, and increase After completing the single-pass tool path trajectory, it moves along the cylindrical surface with a circumferential feed amount of ∆d, and then repeats the single-pass tool path trajectory until the stripping process is completed; during the processing, the coordinates of the entry point P1 on the cutting plane relative to the coordinate origin P0 change from the maximum thickness R and the minimum thickness r of the coating layer machining allowance until the coordinates of the two points finally coincide, and the cutting plane where points P1 and P2 are located gradually moves from perpendicular to the x0y plane to an angle of (90°-θ) with the x0y plane, and the coordinates of the lift point relative to the entry point are or Dynamically change the independent variable.

7. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 or 6, characterized in that: The coordinates of point P2 (x2, y2, zL) are determined by the coordinates of point P1 (x1, y1, z) on the cylindrical surface. Therefore, a binary function Z=f(x1, y1) is constructed based on points P1 and P2. The differential of the above binary function is the tangent plane where points P1 and P2 are located. The directional derivative of the maximum value from the entry point P1 to the lift point P2 on the cutting plane is: ； The directional derivative of the minimum value from the entry point P1 to the lift point P2 on the cutting plane is: ； Where: It represents the directional derivative of the binary function at the entry point P1 (x1, y1, z1) where the machining allowance has the maximum thickness R; It represents the directional derivative of the binary function at the entry point P1 (x1, y1, z1) where the machining allowance has the minimum thickness r; It indicates the distance from point P1 to point P2 on the cutting plane when the machining allowance is at the maximum thickness R; It represents the distance from point P1 to point P2 on the cutting plane when the machining allowance is minimum thickness r.

8. The method for directional stripping of a high-voltage cable sheath based on directional derivative guidance according to claim 1 is characterized in that: After S4, the steps of stripping quality inspection are also included: After the processing is completed, the pencil cone area after the insulation shielding layer is stripped is manually checked. If quality problems such as steps, pits, canine edges and burrs appear, it is necessary to repeat steps S2 and S3, replace the tool with a smaller model, and simultaneously reduce the circumferential step distance △d. Then, repeat the stripping process according to step S4 until the quality of the cone area after the insulation shielding layer is stripped meets the requirements.

9. A device for directional stripping of high-voltage cable sheath based on directional derivative guidance, characterized in that: A method for directional stripping of a high-voltage cable sheath based on directional derivative guidance as described in any one of claims 1 to 8, the device comprising an annular frame (10), a clamping and locking device (20), a motion mechanism (30), a laser scanning device (40), a slide assembly (50) and an electric spindle (60), wherein at least two clamping and locking devices (20) for clamping a high-voltage cable (1) are mounted on the annular frame (10), a motion mechanism (30) is mounted at one end of the annular frame (10), the motion mechanism (30) is capable of rotating along the annular frame (10), a laser scanning device (40) and a slide assembly (50) are mounted on the motion mechanism (30), an electric spindle (60) is mounted on the slide assembly (50), and a tool (61) is mounted on the rotating shaft of the electric spindle (60); It also includes a three-dimensional measurement camera (70) and a controller (80), and the laser scanning device (40), the slide assembly (50), the electric spindle (60) and the three-dimensional measurement camera (70) are respectively connected to the controller (80) for communication.

10. The device for directional stripping of high-voltage cable sheath based on directional derivative guidance according to claim 9 is characterized in that: The slide assembly (50) comprises an X-axis slide (51), a Z-axis slide (52), a lifting seat (53), a rotating seat (54) and a servo motor (55); the X-axis slide (51) is mounted on the motion mechanism (30); the Z-axis slide (52) is mounted on the sliding seat of the X-axis slide (51); the lifting seat (53) is mounted on the sliding seat of the Z-axis slide (52); a rotating shaft is fixedly connected to the lower end of the rotating seat (54); the rotating shaft passes through the lifting seat (53); and the rotating shaft is rotatably connected to the lifting seat (53); the electric spindle (60) is mounted on the rotating seat (54); the servo motor (55) is mounted on the lifting seat (53); and the output shaft of the servo motor (55) is drivingly connected to the rotating shaft of the rotating seat (54).

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