CN108356828B - Workpiece coordinate system correction method - Google Patents
Workpiece coordinate system correction method Download PDFInfo
- Publication number
- CN108356828B CN108356828B CN201810087781.0A CN201810087781A CN108356828B CN 108356828 B CN108356828 B CN 108356828B CN 201810087781 A CN201810087781 A CN 201810087781A CN 108356828 B CN108356828 B CN 108356828B
- Authority
- CN
- China
- Prior art keywords
- workpiece
- coordinate system
- end tool
- point
- cloud data
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/0081—Programme-controlled manipulators with master teach-in means
Landscapes
- Engineering & Computer Science (AREA)
- Robotics (AREA)
- Mechanical Engineering (AREA)
- Numerical Control (AREA)
Abstract
The invention belongs to the technical field of machining, and particularly relates to a workpiece coordinate system correction method, which comprises the steps of firstly, approaching three characteristic points on a workpiece by using a tail end tool piece of a robot to obtain coordinates of each characteristic point, establishing a primary workpiece coordinate system, and then planning a track of the tail end tool piece by using offline programming software; moving the end tool part to each characteristic point according to the track again, and scanning by using a three-dimensional scanner to obtain point cloud data of the end tool part and the workpiece; in the reverse software of a computer, geometric models of the end tool piece and the workpiece are established according to the point cloud data, and finally actual deviations of the end tool piece and each feature point are respectively measured in the geometric models, and a preliminary workpiece coordinate system is corrected according to the actual deviations. According to the workpiece coordinate system correcting method, the actual deviation can be accurately obtained by adopting a three-dimensional scanning mode, the preliminary workpiece coordinate system is corrected according to the actual deviation, and the problem of large error in a manual teaching mode can be solved.
Description
Technical Field
The invention belongs to the technical field of machining, and particularly relates to a workpiece coordinate system correction method.
Background
Because the robot has the advantages of high degree of freedom, good flexibility and the like, the robot is more and more widely applied to the aspect of mechanical processing. The motion trail of the robot is planned by off-line programming software, and most tasks of the off-line programming software are completed based on an object coordinate system, so the accuracy of the object coordinate plays a very important role in the off-line programming software and the robot path planning. Whether the workpiece coordinate system is accurate or not directly affects the processing quality and the processing precision of the part, and even possibly affects the processing safety of the robot.
The current common method for calibrating the robot workpiece coordinate system is to adopt a manual teaching method, and obtain the coordinate values of the feature points on the workpiece by enabling the points on the end tool piece to be as close to the feature points of the workpiece as possible, wherein the coordinate values of the feature points are obtained in the workpiece coordinate system through software calculation. The method adopts a manual teaching mode, the characteristic points of the workpiece are close to the points on the end tool piece of the robot through visual observation, the error is large, and the characteristic points of the workpiece are obtained and are influenced by factors such as the surface quality and the shape of the workpiece, and a certain error also exists, so the error of the workpiece coordinate system calibrated by the manual teaching mode is large.
Disclosure of Invention
The invention aims to solve the technical problem that a workpiece coordinate system in the prior art has a large error in measurement.
In order to achieve the purpose, the invention adopts the technical scheme that: a method of correcting a coordinate system of an object, comprising the steps of:
s10: acquiring a preliminary workpiece coordinate system: providing a robot and a workpiece, respectively approaching three feature points on the workpiece by using a tail end tool piece of the robot, obtaining coordinate values of the three feature points, and calculating according to the coordinate values of the three feature points to obtain a preliminary workpiece coordinate system;
s20: acquiring a terminal tool track: inputting the coordinate values of the characteristic points into offline programming software of the robot, and obtaining the track of the end tool piece;
s30: acquiring point cloud data: providing a three-dimensional scanner, starting the three-dimensional scanner to scan the workpiece and the end tool piece when the end tool piece moves to each characteristic point according to the track of the end tool piece, and obtaining point cloud data of the workpiece and the end tool piece;
s40: reconstructing a geometric model: providing a computer, importing the point cloud data into reverse software of the computer for processing, and obtaining geometric models of the workpiece and the end tool;
s50: obtaining a measurement error: respectively acquiring actual deviations between the geometric model of the end tool piece and the characteristic points on the geometric model of each workpiece by using the reverse software;
s60: correcting a preliminary workpiece coordinate system: and correcting the preliminary workpiece coordinate system according to each actual deviation in the offline programming software.
Further, after the step S60, the steps S20 to S60 are repeated.
Further, in step S10, the approaching of the end tool of the robot to the feature points on the three workpieces respectively is specifically: and selecting one point on the end tool piece as a marking point of the end tool piece, and enabling the marking point to be close to each characteristic point.
Further, the marking point is an origin, an intersection or a center point of a characteristic line on the end tool.
Further, in step S10, the end tool of the robot is used to approach to the feature points on the three workpieces, and the coordinate values of the three feature points are obtained as follows: and selecting a point on the tail end tool piece as a marking point of the tail end tool piece, predicting a preliminary deviation of the relative position between the marking point and the characteristic point when the marking point is close to each characteristic point, and inputting the preliminary deviation into the off-line programming software of the robot to acquire the coordinate value of each characteristic point.
Further, the step S60 specifically includes: and comparing the preliminary deviation with the actual deviation to obtain a relative deviation, and correcting the preliminary workpiece coordinate system according to the relative deviation.
Further, the step S40 specifically includes the following steps:
s41: point cloud data preprocessing: providing a computer, importing the point cloud data into reverse software of the computer, and preprocessing the point cloud data by using the reverse engineering software of the computer;
s42: reconstructing a curved surface: performing curved surface reconstruction on the point cloud data by using the reverse engineering software to obtain a geometric model of the end tool piece and the workpiece;
s43: data alignment: aligning the geometric model with the point cloud data.
Further, in the step S41, the preprocessing performed on the point cloud data includes removing noise points, removing redundant data, and filtering the point cloud data.
Further, in step S42, the surface reconstruction of the point cloud data with the required features includes surface fitting, plane fitting, curve fitting, surface stitching, and feature modeling.
Further, the step S50 is specifically: and establishing auxiliary surfaces, auxiliary lines and auxiliary points on the geometric model of the end tool piece and/or the geometric model of the workpiece by using inverse software to acquire the actual deviation.
The invention has the beneficial effects that: the invention relates to a workpiece coordinate system correction method, which comprises the steps of firstly, acquiring coordinate values of three characteristic points in a traditional manual teaching mode, namely, acquiring coordinates of each characteristic point by using a tail end tool piece of a robot to approach the three characteristic points on a workpiece; and calculating a preliminary workpiece coordinate system according to the obtained coordinate values, inputting the coordinate values of the characteristic points into offline programming software of the robot to obtain a motion track of the robot end tool, scanning point cloud data of the end tool and the workpiece by using a three-dimensional scanner when the robot end tool approaches the characteristic points according to a path planned by the offline programming software, obtaining a geometric model of the end tool and the workpiece by using the point cloud data processed by a computer, simultaneously measuring actual deviation between the end tool and each characteristic point, and correcting the preliminary workpiece coordinate system according to the actual deviation. According to the workpiece coordinate system correction method, the deviation values between the end tool piece and each characteristic point can be accurately and respectively obtained in a three-dimensional scanning mode, the preliminary workpiece coordinate system determined in the manual teaching mode is corrected according to the deviation values, and the problem of large errors of the manual teaching mode can be solved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.
Fig. 1 is a flowchart of a method for correcting a coordinate system of an object according to an embodiment of the present invention.
Fig. 2 is a flowchart of step S40 in the method for correcting the object coordinate system according to the embodiment of the present invention.
Fig. 3 is a schematic structural diagram of an apparatus for correcting a workpiece coordinate system according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of an end tool block of an apparatus for correcting a workpiece coordinate system according to an embodiment of the present invention.
Fig. 5 is an exploded view of a three-dimensional scanner of the apparatus for correcting a coordinate system of a workpiece according to an embodiment of the present invention.
Wherein, in the figures, the respective reference numerals:
10-robot 11-end tool piece 20-three-dimensional scanner
21-camera 22-supporting tripod 30-workpiece
111-semi-cylinder 112-square bulge 221-mounting block
222-connecting component 223-supporting rod 224-connecting plate
225-fixing screw 226-fastening screw 2211-hinge groove
2212-straight slot 2213-fastening hole 2221-first connecting rod
2222-second connecting rod 2223-adjusting nut 2224-hinge ball
2241-holding groove 2242-first fixed orifices 2231-second fixed orifices.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to fig. 1-5 are exemplary and intended to be used for explanation of the invention, and should not be construed as limiting the invention.
In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating 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 the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
As shown in fig. 1 to 2, an embodiment of the present invention provides a method for correcting a coordinate system of a workpiece, including the following steps:
s10: acquiring a preliminary workpiece coordinate system: providing a robot 10 and a workpiece 30, respectively approaching three feature points (not shown) on the workpiece 30 by using an end tool piece 11 of the robot 10, obtaining coordinate values of the three feature points, and calculating according to the coordinate values of the three feature points to obtain a preliminary workpiece coordinate system;
s20: acquiring a terminal tool track: inputting the coordinate values of the feature points into offline programming software of the robot 10, and obtaining the track of the end tool piece 11;
s30: acquiring point cloud data: providing a three-dimensional scanner 20, starting the three-dimensional scanner 20 to scan the workpiece 30 and the end tool 11 when the end tool 11 moves to each feature point according to the track of the end tool 11, and obtaining point cloud data of the workpiece 30 and the end tool 11;
s50: and (3) measuring actual deviation: respectively acquiring actual deviations between the geometric model of the end-tooling piece 11 and the feature points on the geometric model of each workpiece 30 by using the inverse software;
s60: correcting a preliminary workpiece coordinate system: and correcting the preliminary workpiece coordinate system according to each actual deviation in the offline programming software.
Specifically, in the method for correcting the workpiece coordinate system according to the embodiment of the present invention, coordinate values of three feature points on the workpiece 30 are first obtained through a conventional manual teaching method, that is, the end tool 11 of the robot 10 is used to approach the three feature points on the workpiece 30 to obtain coordinates of each feature point; and then calculating a preliminary workpiece coordinate system according to the obtained coordinate values, inputting the coordinate values of all the feature points into offline programming software of the robot 10 to obtain a motion track of the end tool 11 of the robot 10, when the end tool 11 of the robot 10 moves to all the feature points according to a path planned by the offline programming software, scanning point cloud data of the end tool 11 and the workpiece 30 by using a three-dimensional scanner 20, processing the point cloud data by using reverse software in a computer to obtain a geometric model of the end tool 11 and the workpiece 30, simultaneously measuring actual deviation between the end tool 11 and each feature point, and correcting the preliminary workpiece coordinate system according to the actual deviation. According to the workpiece coordinate system correction method, the actual deviation between the tail end workpiece 30 and the characteristic points can be accurately obtained in a three-dimensional scanning mode, the preliminary coordinate system determined in the manual teaching mode is corrected according to the actual deviation, and the problem of large errors of the manual teaching mode can be solved.
Further, when point cloud data is obtained, the three-dimensional scanner 20 may be used to obtain point cloud data of the workpiece 30 and the end tooling 11 at a first feature point to generate first point cloud data, then the three-dimensional scanner 20 may be used to obtain point cloud data of the workpiece 30 and the end tooling 11 at a second feature point to generate second point cloud data, and so on, the three-dimensional scanner 20 may be used to obtain point cloud data of the workpiece 30 and the end tooling 11 at a third feature point to generate third point cloud data, the first point cloud data, the second point cloud data, and the third point cloud data are processed respectively to obtain geometric models of the three end tooling and the workpiece respectively, and then actual deviations between the end tooling 11 and each feature point are measured respectively.
Of course, in other embodiments, when the point cloud data is obtained, after the three-dimensional scanner 20 obtains the point cloud data of the workpiece 30 and the end tool 11 once at the first feature point, the three-dimensional scanner 20 continues to obtain the point cloud data of the workpiece 30 and the end tool 11 on the basis of the point cloud data of the last time at the second feature point, and the three-dimensional scanner 20 continues to obtain the point cloud data of the workpiece 30 and the end tool 11 on the basis of the point cloud data of the last time at the third feature point, and the finally obtained point cloud data has the point cloud data of one workpiece 30 and three end tools 11 respectively close to the corresponding feature points, and a geometric model file is obtained through the processing of the computer, and then the actual deviations between the end tool 11 and each feature point are respectively measured.
Further, when the three-dimensional scanner 20 scans, the point cloud data of the entire workpiece 30 may be obtained by scanning to obtain more accurate point cloud data, or only a part of the point cloud data at each feature point on the workpiece 30 may be obtained to ensure that the feature points can be accurately obtained in the processed geometric model.
In this embodiment, after the step S60, the steps S20 to S60 are repeated. Specifically, the preliminary coordinate system may be modified through the steps S20 to S60 several times to obtain a more accurate workpiece coordinate system.
In this embodiment, in the step S10, the approaching of the end tool 11 of the robot 10 to the three feature points on the workpiece 30 is specifically: any point on the end tool 11 is selected as a mark point (not shown) of the end tool 11, and the mark point is close to each feature point. Specifically, the preliminary deviation between the mark point and the feature point is equivalent to determining the deviation between the point and the feature point, and the deviation between the point and the feature point is easily determined by a simple operation performed by experience, the naked eye, or with a simple tool such as a ruler.
In this embodiment, the mark point is an origin, an intersection, or a center of a characteristic line on the end tool 11. Specifically, when the mark point is the origin, intersection or center point of the geometric feature line on the end tooling member 11, the mark point is easily found in the physical mark member, and the deviation between the mark point and the feature point of the workpiece 30 is also easily determined, and also easily determined in the geometric model of the mark member.
Of course, in other embodiments, the marked points may also be other geometric feature points of the end tooling member 11.
It should be noted that the characteristic line on the end tool 11 may specifically be an edge line on the solid model of the end tool 11 or a geometric line possessed by the edge line, so as to easily determine the mark point in the geometric model of the end tool 11.
In this embodiment, in the step S10, the end tool 11 of the robot 10 is used to approach three feature points on the workpiece 30, and coordinate values of the three feature points are obtained as follows: selecting a point on the end tool part 11 as a marking point of the end tool part 11, predicting a preliminary deviation of the relative position between the marking point and the feature point when the marking point is close to each feature point, and inputting the preliminary deviation into offline programming software of the robot 10 to obtain coordinate values of each feature point. Specifically, the initial deviation between the mark point and the feature point is equivalent to the deviation between the determined point and the feature point, the deviation between the point and the feature point is easily determined through simple operations of experience, naked eyes or by means of simple tools such as a ruler, and the method is also suitable for the situation that the mark point cannot be completely overlapped with the feature point. Because the coordinates of the marking points are known, the coordinate values of the characteristic points can be directly obtained by inputting the initial deviation into the off-line programming software.
In this embodiment, the step S60 specifically includes: and comparing the preliminary deviation with the actual deviation to obtain a relative deviation, and correcting the preliminary workpiece coordinate system according to the relative deviation. Specifically, the relative deviation between the preliminary deviation and the actual deviation is input into the offline programming software to correct the coordinate values of the feature points, so that more accurate coordinate values are obtained, and then the preliminary coordinate system is corrected according to the more accurate coordinate values, so that a more accurate coordinate system can be obtained.
Further, the actual deviation, the preliminary deviation and the relative deviation may be lengths and/or angles of connecting lines between the mark points and the feature points on the end tooling member 11, etc., so that the preliminary coordinate system can be more accurately repaired.
In this embodiment, referring to fig. 2, the step S40 specifically includes the following steps:
s41: point cloud data preprocessing: providing a computer, importing the point cloud data into reverse software of the computer, and preprocessing the point cloud data by using the reverse engineering software of the computer;
s42: reconstructing a curved surface: performing surface reconstruction on the point cloud data by using the reverse engineering software to obtain a geometric model of the end tool piece 11 and the workpiece 30;
s43: data alignment: aligning the geometric model with the point cloud data.
Specifically, the imported point cloud data is screened, some point cloud data is deleted to reduce the workload of curved surface reconstruction and enable the reconstructed curved surface to be closer to a real part, a geometric model of the end tool 11 and the workpiece 30 is established according to the screened point cloud data, and finally the generated geometric model and the point cloud data are aligned to ensure the accuracy of the geometric model.
In this embodiment, in the step S41, the preprocessing performed on the point cloud data includes removing noise points, removing redundant data, and filtering the point cloud data. Specifically, in the process of acquiring the point cloud data, unreasonable noise points are inevitably mixed, the reconstructed curve and curved surface are not smooth, and the elimination of the noise points enables the reconstructed geometric model to be closer to the actual shapes of the end tool piece 11 and the workpiece 30, so that a more accurate geometric model is obtained, and the machining precision is improved. In the process of acquiring the point cloud data, in order to accurately acquire surface details of the end tool 11 and the workpiece 30 and also have more redundant point clouds, the difficulty of geometric model reconstruction is increased by a large amount of redundant data, and the difficulty and workload of geometric model reconstruction can be simplified by removing the redundant data. And filtering some abnormal data in some point cloud data to obtain a better curved surface reconstruction effect.
Further, in step S41, the method further includes performing secondary sampling on the marker and the curved surface part, performing data sorting, data splicing, data reorganization, feature extraction, and region division on the point cloud data, and then triangulating discrete points in the point cloud data to form transition curved surface model data, wherein the feature extraction includes local separation, approximation, fairing, and splicing, and the triangulation includes performing triangular surface continuous interpolation on the point cloud data, and fairing and deforming a triangular surface to obtain a more accurate geometric model of the end tool 11 and the workpiece 30.
In this embodiment, in the step S42, the performing surface reconstruction on the point cloud data with the required features includes surface fitting, plane fitting, curve fitting, surface stitching, and feature modeling. Specifically, the computer performs surface reconstruction on the processed point cloud data to obtain a geometric model, wherein the surface reconstruction includes curve fitting, surface splicing and characteristic modeling, and the geometric model is finally obtained.
Further, the surface fitting comprises extracting and separating quadric surfaces, and the surface splicing comprises smoothly splicing adjacent surface blocks and coordinating smooth global surface blocks.
In this embodiment, the step S50 specifically includes: using inverse software, auxiliary surfaces, auxiliary lines and auxiliary points are created on the geometric model of the end-tooling 11 and/or on the geometric model of the workpiece 30 to obtain the actual deviations. Specifically, it is possible to make the measurement of the actual deviation more convenient and reduce the difficulty of the measurement operation by establishing the auxiliary lines, and auxiliary points on the geometric model of the end-tooling 11 and/or the geometric model of the workpiece 30.
As shown in fig. 3 to 5, an embodiment of the invention further provides an apparatus for correcting a workpiece coordinate system, which is mainly used for implementing the workpiece coordinate system correction method. The device for correcting the coordinate system of the workpiece comprises a robot 10 and a three-dimensional scanner 20 located on the side portion of the robot 10, wherein the tail end of the robot 10 is provided with a tail end tool piece 11 used for detecting characteristic points on the workpiece 30, the tail end tool piece 11 is arranged close to the workpiece 30, the three-dimensional scanner 20 comprises a camera, and the camera is arranged right opposite to the workpiece 30 and the tail end tool piece 11 and used for acquiring point cloud data of the workpiece 30 and the point cloud data of the tail end tool piece 11. Specifically, in the device for correcting the workpiece coordinate system according to the embodiment of the present invention, when the device is used specifically, the manual teaching method is firstly adopted, the end tool 11 on the mobile robot 10 approaches to the feature points on the workpiece 30 and obtains the coordinate values of the feature points, and then the preliminary workpiece coordinate system can be determined according to the coordinate values of the feature points. Then, the motion trajectory of the end tooling part 11 is planned according to the off-line programming software in the robot 10, so that the end tooling part 11 moves to each feature point according to the trajectory, the three-dimensional scanner 20 is used for scanning the workpiece 30 and the end tooling part 11 at the same time, point cloud data of the workpiece 30 and the end tooling part 11 is obtained, then data processing and analysis are carried out on the point cloud data in the reverse software of the computer to obtain a geometric model of the end tooling part 11 and the workpiece 30, actual deviations between the feature points on the end tooling part 11 and the workpiece 30 are respectively measured, at this time, only the preliminary workpiece coordinate system needs to be translated or rotated in the off-line programming software according to the actual deviations, and the workpiece coordinate system can be corrected, and a more accurate workpiece coordinate system can be obtained.
In this embodiment, referring to fig. 4, the end tool 11 is a semi-cylinder 111. Specifically, the characteristic points on the workpiece 30 are approached by the semi-cylindrical arc surface. When the feature point is located at the concave portion of the surface of the workpiece 30, the arc surface of the semi-cylinder can be as close to the feature point as possible, so that the coordinate system of the feature point obtained by the manual teaching method is more accurate, and the application range of the end tool piece 11 is also increased. Meanwhile, the semi-cylinders 111 belong to regular components, point cloud data of the semi-cylinders are easy to process, the precision of the geometric figures obtained through processing is high, and the precision of a workpiece coordinate system is further improved.
In this embodiment, referring to fig. 4, a square protrusion 112 is disposed on a plane of the semicircular body opposite to the arc surface. Specifically, the edge of the square protrusion 112 can make the end tool 11 close to the feature point on the complex-shaped workpiece 30 as much as possible, so that the coordinate system of the feature point obtained by the manual teaching method is more accurate. Meanwhile, the square protrusion 112 belongs to a regular component, the point cloud data of the square protrusion 112 is easy to process, the precision of the geometric figure obtained by processing is high, and the precision of the workpiece coordinate system is further improved.
In this embodiment, the three-dimensional scanner 20 is a binocular three-dimensional scanner. Specifically, the binocular three-dimensional scanner 20 combines a structured light technology, a phase measurement technology, and a composite three-dimensional non-contact measurement technology of a computer vision technology, and adopts a blue light raster scanning mode to realize full-automatic splicing of point cloud data, so that the binocular three-dimensional scanner 20 has the advantages of high efficiency, high precision, long service life, high resolution and the like, can meet the scanning requirements of a workpiece 30 with high detail requirements, and can obtain accurate point cloud data of the end tool piece 11 and the workpiece 30 at the same time.
In this embodiment, referring to fig. 3, the three-dimensional scanner 20 further includes a supporting tripod 22, and the camera 21 is fixedly mounted on an upper portion of the supporting tripod 22. Specifically, the supporting tripod 22 can reliably support the camera 21, and avoid shaking of the camera 21, thereby affecting the accuracy of the scanned point cloud data.
In this embodiment, referring to fig. 5, the supporting tripod 22 includes a mounting block 221, a connecting assembly 222 and three supporting rods 223, top ends of the three supporting rods 223 are all connected to a bottom end of the mounting block 221, the three supporting rods 223 are radially inclined, and the camera 21 is mounted on the top end of the mounting block 221 through the connecting assembly 222. Specifically, three bracing piece 223 is that the triangle is to taking the form to be fixed in the bottom of installation piece 221, and the top of installation piece 221 passes through coupling assembling 222 and links to each other with camera 21, because the triangular supports comparatively firm, can stably support camera 21, and bracing piece 223's simple structure, with low costs, occupation space is little, has expanded three-dimensional scanner 20's application scope.
Further, referring to fig. 5, the supporting tripod 22 further includes a connecting plate 224, the top end of the connecting plate 224 is fixedly mounted at the bottom end of the mounting block 221, three holding grooves 2241 for accommodating the top end of the supporting rod 223 are formed in the connecting plate 224, the supporting rod 223 can swing up and down in the holding groove 2241, a first fixing hole 2242 penetrating through the holding groove 2241 is formed in the side surface of the holding groove 2241, a second fixing hole 2231 is formed in the corresponding position of the first fixing hole 2242 at the top end of the supporting rod 223, and the fixing screws 225 are used for sequentially penetrating through the first fixing hole 2242 and the second fixing hole 2231 to fix the supporting rod 223 on the connecting plate 224. Can be through the fastening of set screw 225 and the effect of loosening, the realization is the triangle and to taking in and opening of the bracing piece 223 of form, also can realize the dismantlement of bracing piece 223, is convenient for support the taking in of tripod 22.
In this embodiment, the support rod 223 is a telescopic rod. Specifically, the height of the support rod 223 is adjustable, and the height of the camera 21 is adjusted by adjusting the height of the support rod 223, so that the scanner can perform complete scanning on workpieces 30 with different sizes, and the condition that the workpieces 30 are not scanned is avoided.
In this embodiment, referring to fig. 5, the connection assembly 222 includes a first connection rod 2221, a second connection rod 2222, and an adjustment nut 2223, a bottom end of the second connection rod 2222 is connected to the mounting block 221, a top end of the second connection rod 2222 is inserted into a threaded hole of the adjustment nut 2223, a top end of the second connection rod 2222 is provided with an external thread adapted to the adjustment nut 2223, a bottom end of the first connection rod 2221 is provided with an internal thread matched with the external thread so that the first connection rod 2221 is in threaded connection with the second connection rod 2222, and the camera 21 is fixedly connected to the top end of the first connection rod 2221. Specifically, the top end of the second connecting rod 2222 first passes through the adjusting nut 2223, then the top end of the second connecting rod 2222 is connected with the top end of the first connecting rod 2221 through the threaded connection between the first connecting rod 2221 and the second connecting rod 2222, the height of the camera 21 fixed to the top end of the first connecting rod 2221 can be adjusted, meanwhile, the upper surface of the adjusting nut 2223 can be abutted against the lower surface of the first connecting rod 2221 through rotation of the adjusting nut 2223, the loosening condition caused by the threaded connection between the first connecting rod 2221 and the second connecting rod 2222 is avoided, and the stability of fixing the camera 21 is ensured.
In this embodiment, referring to fig. 5, the bottom end of the second connecting rod 2222 is provided with a hinge ball 2224 fixed to the second connecting rod 2222, the inside of the mounting block 221 is provided with a hinge slot 2211 matched with the hinge ball 2224, and the hinge ball 2224 is hinged to the hinge slot 2211 so that the second connecting rod 2222 is hinged to the mounting block 221. Specifically, the top end of the second connecting rod 2222 is hinged to the mounting block 221 through the hinge ball 2224 and the hinge slot 2211, so that the second connecting rod 2222 is rotatably connected to the mounting block 221, that is, the camera 21 can be rotated without moving the supporting rod 223, and the three-dimensional scanner 20 is more convenient to use and simpler to operate.
Further, as shown in fig. 5, the mounting block 221 is further provided with a straight slot 2212 communicating with the hinge slot 2211, the straight slot 2212 can accommodate the top of the second connecting rod 2222, the height of the camera 21 can be adjusted and rotated by the rotation of the second connecting rod 2222 in the hinge slot 2211 and the vertical rotation in the straight slot 2212, the adjustable angle and the adjustable height of the camera 21 are increased, the scanning range of the three-dimensional scanner 20 is increased, and the three-dimensional scanner can be applied to a wider variety of workpieces 30.
In this embodiment, referring to fig. 5, the supporting tripod 22 further includes a fastening screw 226, a fastening hole 2213 communicating with the hinge slot 2211 and through which the fastening screw 226 passes is disposed on a side surface of the mounting block 221, the fastening screw 226 passes through the fastening hole 2213, and a tip of the fastening screw 226 abuts against the hinge ball 2224. Specifically, by abutting the tip of the fastening screw 226 on the hinge ball 2224, the hinge ball 2224 can be fixed so that the hinge ball 2224 cannot rotate, thereby fixing the scanning angle of the camera 21 and ensuring the stability of the camera 21 during scanning.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. A method of correcting a coordinate system of an object, comprising the steps of:
s10: acquiring a preliminary workpiece coordinate system: providing a robot and a workpiece, respectively approaching three feature points on the workpiece by using a tail end tool piece of the robot, obtaining coordinate values of the three feature points, and calculating according to the coordinate values of the three feature points to obtain a preliminary workpiece coordinate system;
s20: acquiring a terminal tool track: inputting the coordinate values of the characteristic points into offline programming software of the robot, and obtaining the track of the end tool piece;
s30: acquiring point cloud data: providing a three-dimensional scanner, starting the three-dimensional scanner to scan the workpiece and the end tool piece when the end tool piece moves to each feature point according to the track of the end tool piece, and obtaining point cloud data containing the workpiece and the end tool piece;
s40: reconstructing a geometric model: providing a computer, importing the point cloud data into reverse software of the computer for processing, and obtaining a geometric model containing the workpiece and the end tool;
s50: obtaining a measurement error: respectively acquiring actual deviations between the geometric model of the end tool piece and the characteristic points on the geometric model of each workpiece by using the reverse software;
s60: correcting a preliminary workpiece coordinate system: and correcting the preliminary workpiece coordinate system according to each actual deviation in the offline programming software.
2. The object coordinate system correction method according to claim 1, characterized in that: after the step S60, steps S20 to S60 are repeated.
3. The object coordinate system correction method according to claim 1, characterized in that: in step S10, the steps of respectively approaching the three feature points on the workpiece by using the end tool of the robot are specifically: and selecting one point on the end tool piece as a marking point of the end tool piece, and enabling the marking point to be close to each feature point.
4. The object coordinate system correction method according to claim 3, characterized in that: the marking point is an origin, an intersection or a center point of a characteristic line on the end tooling piece.
5. The object coordinate system correction method according to claim 1, characterized in that: in step S10, the end tool of the robot is used to approach the three feature points on the workpiece, and the coordinate values of the three feature points are obtained as follows: and selecting a point on the tail end tool piece as a marking point of the tail end tool piece, predicting a preliminary deviation of the relative position between the marking point and the characteristic point when the marking point is close to each characteristic point, and inputting the preliminary deviation into the off-line programming software of the robot to obtain the coordinate value of each characteristic point.
6. The object coordinate system correction method according to claim 5, characterized in that: the step S60 specifically includes: and comparing the preliminary deviation with the actual deviation to obtain a relative deviation, and correcting the preliminary workpiece coordinate system according to the relative deviation.
7. The method of correcting a workpiece coordinate system according to any one of claims 1 to 6, characterized in that: the step S40 specifically includes the following steps:
s41: point cloud data preprocessing: providing a computer, importing the point cloud data into reverse software of the computer, and preprocessing the point cloud data by using the reverse engineering software of the computer;
s42: reconstructing a curved surface: performing curved surface reconstruction on the point cloud data by using the reverse engineering software to obtain a geometric model of the end tool piece and the workpiece;
s43: data alignment: aligning the geometric model with the point cloud data.
8. The object coordinate system correction method according to claim 7, characterized in that: in the step S41, the preprocessing performed on the point cloud data includes removing noise points, removing redundant data, and filtering the point cloud data.
9. The object coordinate system correction method according to claim 7, characterized in that: in step S42, performing surface reconstruction on the point cloud data with the required features includes surface fitting, plane fitting, curve fitting, surface stitching, and feature modeling.
10. The method of correcting a workpiece coordinate system according to any one of claims 1 to 6, characterized in that: the step S50 specifically includes: and establishing auxiliary surfaces, auxiliary lines and auxiliary points on the geometric model of the end tool piece and/or the geometric model of the workpiece by using inverse software to acquire the actual deviation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810087781.0A CN108356828B (en) | 2018-01-30 | 2018-01-30 | Workpiece coordinate system correction method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810087781.0A CN108356828B (en) | 2018-01-30 | 2018-01-30 | Workpiece coordinate system correction method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108356828A CN108356828A (en) | 2018-08-03 |
| CN108356828B true CN108356828B (en) | 2021-01-15 |
Family
ID=63007528
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810087781.0A Active CN108356828B (en) | 2018-01-30 | 2018-01-30 | Workpiece coordinate system correction method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108356828B (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108871649B (en) * | 2018-08-14 | 2020-07-14 | 坤维（北京）科技有限公司 | Method for establishing reference coordinate system |
| CN109514133B (en) * | 2018-11-08 | 2020-09-11 | 东南大学 | 3D curve welding seam autonomous teaching method of welding robot based on line structure light perception |
| CN109759894A (en) * | 2018-11-23 | 2019-05-17 | 常州创领机械有限公司 | A kind of numerical-control processing method of brake head |
| CN109814434B (en) * | 2018-12-20 | 2020-02-21 | 北京华航唯实机器人科技股份有限公司 | Calibration method and device of control program |
| CN111400830B (en) * | 2019-01-03 | 2023-07-11 | 西北工业大学太仓长三角研究院 | Machining calibration method and device for three-dimensional blank workpiece |
| CN109807890B (en) * | 2019-01-31 | 2020-02-28 | 北京华航唯实机器人科技股份有限公司 | Equipment error calibration method and device |
| CN109903333B (en) * | 2019-02-02 | 2021-02-09 | 宁波吉利汽车研究开发有限公司 | Coordinate system correction method and device for robot workpiece and electronic equipment |
| CN110142748A (en) * | 2019-07-15 | 2019-08-20 | 常州固高智能装备技术研究院有限公司 | A kind of quick teaching system of robot suitable for spraying welding profession and method |
| CN110487233B (en) * | 2019-07-30 | 2021-06-15 | 东莞长盈精密技术有限公司 | Method and system for correcting robot user coordinate system |
| CN112642619A (en) * | 2019-10-10 | 2021-04-13 | 中国科学院重庆绿色智能技术研究院 | Intelligent spraying robot system and spraying method thereof |
| CN111409075A (en) * | 2020-04-22 | 2020-07-14 | 无锡中车时代智能装备有限公司 | Simple and convenient robot hand-eye calibration system and calibration method |
| CN111552234B (en) * | 2020-05-12 | 2021-08-20 | 广州达意隆包装机械股份有限公司 | Processing technology for four-axis linkage processing of sealing guide rail of bottle blowing machine |
| CN112578730A (en) * | 2020-11-16 | 2021-03-30 | 中国航发西安动力控制科技有限公司 | Method for quickly converting reference coordinates in self-adaptive machining |
| CN114670192A (en) * | 2022-03-16 | 2022-06-28 | 江西瑞祥智能装备有限公司 | Calibration method and device for robot workpiece coordinate system, storage medium and terminal |
| CN114529652B (en) * | 2022-04-24 | 2022-07-19 | 深圳思谋信息科技有限公司 | Point cloud compensation method, device, equipment and storage medium |
| CN114905516A (en) * | 2022-05-30 | 2022-08-16 | 北京石油化工学院 | Robot initial position finding system and method for large-scale component |
| CN115323163A (en) * | 2022-10-13 | 2022-11-11 | 江苏新恒基特种装备股份有限公司 | Austenitic stainless steel grain size control method, system and storage medium |
| CN116834024B (en) * | 2023-08-31 | 2024-01-26 | 北京集度科技有限公司 | Calibration method, calibration device and medium for robot user coordinate system |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06175716A (en) * | 1992-12-10 | 1994-06-24 | Fanuc Ltd | Position/attitude correcting method for object holding work of manipulator |
| KR100345150B1 (en) * | 2000-09-29 | 2002-07-24 | 현대자동차주식회사 | Method for compensating robot position using laser analyzer |
| JP2006048244A (en) * | 2004-08-02 | 2006-02-16 | Fanuc Ltd | Working program generating device |
| CN103885390B (en) * | 2014-04-09 | 2017-06-20 | 哈尔滨工业大学 | Teaching 3-d laser measurement method and apparatus is exempted from based on reverse Engineering Technology |
| CN104457566A (en) * | 2014-11-10 | 2015-03-25 | 西北工业大学 | Spatial positioning method not needing teaching robot system |
| CN104865897B (en) * | 2015-04-10 | 2017-09-22 | 深圳市圆梦精密技术研究院 | The processing method of curved surface part and the process equipment of curved surface part |
| CN106600681B (en) * | 2016-11-02 | 2023-07-11 | 上海航天设备制造总厂 | Polishing method for curved surface with obstacle |
-
2018
- 2018-01-30 CN CN201810087781.0A patent/CN108356828B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108356828A (en) | 2018-08-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108356828B (en) | Workpiece coordinate system correction method | |
| CN108362240B (en) | Method for acquiring coordinate system of workpiece | |
| CN108127483B (en) | Numerical control machining positioning method for curved surface part | |
| CN111775146B (en) | Visual alignment method under industrial mechanical arm multi-station operation | |
| CN109029293B (en) | Method for calibrating position and pose errors of line scanning measuring head in blade surface type detection | |
| CN108827155B (en) | Robot vision measurement system and method | |
| CN110906863B (en) | Hand-eye calibration system and calibration method for line-structured light sensor | |
| CN105234802A (en) | Small ball head tool single-turntable polishing machining device and tool setting method | |
| CN112907683B (en) | Camera calibration method and device for dispensing platform and related equipment | |
| CN112880592B (en) | Inclination calibration method of numerical control turntable center based on mandrel | |
| CN103791868A (en) | Space calibrating body and method based on virtual ball | |
| CN112097642B (en) | Three-dimensional cross hole position degree detection instrument and detection method | |
| CN109489581B (en) | Large-pitch conical external thread detection device and method | |
| CN112699573B (en) | Reverse modeling method and system of virtual pipeline model and electronic equipment | |
| CN112907682B (en) | Hand-eye calibration method and device for five-axis motion platform and related equipment | |
| CN111649667A (en) | Flange pipeline end measuring method, measuring device and adapter structure | |
| JP7353757B2 (en) | Methods for measuring artifacts | |
| CN109299515B (en) | Workpiece machining error analysis method based on installation error extraction and correction | |
| CN113182932B (en) | Composite machine tool for adjusting workpiece angle based on workpiece appearance scanning data | |
| CN112762822B (en) | Mechanical arm calibration method and system based on laser tracker | |
| CN104316008A (en) | Blade profile measuring-aided device with adjustable postures | |
| CN112504048B (en) | Device and method for measuring height and gradient of radial connecting pipe on regular curved surface | |
| CN114459345A (en) | System and method for detecting position and attitude of airplane body based on visual space positioning | |
| CN113063348A (en) | Structured light self-perpendicularity arc-shaped weld scanning method based on three-dimensional reference object | |
| CN207946851U (en) | Correct workpiece coordinate system device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |