A bulkhead marking robot marking operation calibration method

Abstract

This invention provides a calibration method for a bulkhead marking robot, comprising: installing a laser tracker on the bulkhead to be marked, setting the robot on the bulkhead to be marked, and installing a gyroscope on the robot; calibrating the coordinate system of the laser tracker. s The transformation relationship from bulkhead coordinate system b to the robotic arm coordinate system is obtained. r The ZYX Euler angle variation relationship is used to calibrate the gyroscope zero point; the position of the robot origin in the bulkhead coordinate system b is measured in real time to guide the robot to the target workstation; combining the real-time measured origin position and the gyroscope zero point, the robot's position in the robotic arm coordinate system at that workstation is calculated. r The invention outlines the process of converting robot motion planning data from drawing specifications to on-site application data, providing accurate marking station guidance data and marking point guidance data for LNG bulkhead robots operating on the bulkhead.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ship manufacturing, in particular to a cabin wall line marking robot line marking operation calibration method. BACKGROUND

[0002] In the containment system of the MARK III type LNG transport ship, the insulation box as the outermost insulation material, through the connection of epoxy resin and the inner hull plate of the ship and the combination with the double-layer shielding layer, constitutes the basis of the system installation. The installation quality of the insulation box is directly related to the installation accuracy of the key components such as the secondary shielding, TBP / EOB, main shielding and the overall performance of the system.

[0003] Due to the inevitable deviation between the main size of the inner hull plate and the angle of the finished size and the theoretical data, therefore, before installation, the installation position of the insulation box needs to be determined through accurate measurement and line marking positioning, so as to ensure the continuity of the main shielding and the corrugated plate between different cabin walls.

[0004] The traditional manual line marking positioning method first uses a laser tracker to mark sample points, and then uses a white ink duct line to manually connect to form a grid line. This process not only requires a large amount of manpower and time resources, but also the line marking quality is greatly affected by the technology and experience of the construction personnel, and cumulative line marking errors are easily introduced. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a cabin wall line marking robot line marking operation calibration method.

[0006] According to one aspect of the present application, a cabin wall line marking robot line marking operation calibration method is provided, comprising:

[0007] installing a laser tracker on a to-be-marked ship wall, setting a line marking robot on the to-be-marked ship wall, and installing a gyroscope on the line marking robot;

[0008] calibrating the coordinate system of the laser tracker s to the conversion relationship of the cabin wall coordinate system b ;

[0009] based on the conversion relationship , obtaining the ZYX Euler angle change relationship of the cabin wall coordinate system b to the mechanical arm coordinate system r of the line marking robot, and calibrating the zero point of the gyroscope;

[0010] based on the conversion relationship , measuring the position coordinates of the origin of the line marking robot in the cabin wall coordinate system b in real time, and guiding the line marking robot to reach the target work station based on the position coordinates;

[0011] After the marking robot reaches the workstation, it calculates the robot's position within the robotic arm coordinate system at that workstation by combining the real-time measured origin position and the gyroscope's zero point. r Motion control trajectory Complete the marking and calibration task for a single station.

[0012] Preferably, the calibration laser tracker coordinate system s Transformation relationship to bulkhead coordinate system b ,include:

[0013] Select the origin on the bulkhead coordinate system b. X The outermost point on the axis Y The outermost point on the axis;

[0014] The laser tracker measures the sphere placed on the bulkhead at the origin point, the... X The outermost point on the axis, the Y The coordinate system of the laser tracker is obtained by measuring the coordinates of the three points on the measuring sphere at the outermost edge point on the axis. s The bulkhead in X axis, Y Axis vectors and origin coordinates;

[0015] Through the coordinate system of the laser tracker s The bulkhead in X axis, Y Solve for the Z-axis vector of the bulkhead using axis vectors, and then correct it. Y Axis vectors and guarantees X, Y, Z The three-axis vectors are orthogonal;

[0016] Through pairwise orthogonal X, Y, Z Axial vector solution for bulkhead coordinate system b and laser tracker coordinate system s Rotation matrix between and ;

[0017] By combining the rotation matrix and the origin coordinates of the bulkhead coordinate system b, the relationship between the bulkhead coordinate system b and the laser tracker coordinate system is calculated. s Translation transformation vectors between ;

[0018] Based on the translation transformation vector and the rotation matrix , Obtain the homogeneous transformation matrix from the laser tracker coordinate system to the bulkhead coordinate system. .

[0019] Preferably, the coordinate system of the laser tracker s The bulkhead in X axis,Y Solve for the Z-axis vector of the bulkhead using axis vectors, and then correct it. Y Axis vectors and guarantees X, Y, Z The three-axis vectors are orthogonal, including:

[0020] pass X axis, Y Axis vectors The cross product is obtained perpendicular to vector : ;

[0021] pass The cross product of vectors yields a result perpendicular to the vector. vector : .

[0022] Preferably, the method involves pairwise orthogonal... X, Y, Z Axial vector solution for bulkhead coordinate system b and laser tracker coordinate system s Rotation matrix between and ,include:

[0023] Orthogonal pairs X, Y, Z Axis vectors Normalization yields the rotation matrix. and ,include:

[0024] .

[0025] Preferably, the transformation relationship is based on... Obtain the coordinate system from the bulkhead coordinate system b to the robotic arm coordinate system of the marking robot. r The relationship between the ZYX Euler angles is determined, and the zero point of the gyroscope is calibrated, including:

[0026] The laser tracker acquires the coordinate system of the marking robotic arm on the line-marking robot. X axis, Y The reference indicator points for the axis and origin, and through the aforementioned transformation relationship Mapped to the bulkhead coordinate system b superior;

[0027] By collecting reference indicator point data for the X-axis, Y-axis, and origin of the robotic arm coordinate system, the robotic arm coordinate system can be calculated. r In the bulkhead coordinate system b The calibration rotation matrix below ;

[0028] Through the rotation matrix The robot's Euler angles are cut using the ZYX method;

[0029] The three-axis rotation angle zero point of the robot gyroscope is calibrated by the Euler angle.

[0030] Preferably, the rotation matrix is split into robot Euler angles in ZYX mode, including:

[0031] ;

[0032] ;

[0033] ;

[0034] The rotation matrix is expressed as The corresponding element of the i-th row and j-th column.

[0035] Preferably, after the marking robot reaches the work station position, the zero point of the gyroscope is combined with the origin position measured in real time to calculate the motion control trajectory of the robot in the mechanical arm coordinate system r to complete the single station marking work calibration task, including:

[0036] The mechanical arm origin coordinates are measured in real time by a laser tracker and converted to the mechanical arm coordinate system r;

[0037] The homogeneous transformation matrix b from the bulkhead coordinate system r to the mechanical arm coordinate system is obtained by combining the mechanical arm origin position converted to the mechanical arm coordinate system r and the gyroscope zero angle information;

[0038] The marking target data recorded in the bulkhead coordinate system b is combined with the homogeneous transformation matrix to calculate the marking trajectory of the mechanical arm in the mechanical arm coordinate system ; r

[0039] The mechanical arm performs the marking task according to the obtained marking trajectory .

[0040] Preferably, the mechanical arm origin coordinates are measured in real time by a laser tracker and converted to the mechanical arm coordinate system r, specifically:

[0041] The mechanical arm origin position is collected by a laser tracker;

[0042] The conversion relationship ​​​, to obtain the representation of the robot origin position in the bulkhead coordinate system :

[0043] .

[0044] Preferably, the combination converts the mechanical arm origin position in the mechanical arm coordinate system r, the gyro zero point angle information, to obtain the homogeneous transformation matrix of the bulkhead coordinate system b to the mechanical arm coordinate system r , comprising:

[0045] The zero point angle is used to calculate the rotation matrix of the mechanical arm coordinate system r to the bulkhead coordinate system b , and its inverse matrix ;

[0046] The translation vector of the bulkhead coordinate system b data to the mechanical arm coordinate system r data is ;

[0047] The homogeneous transformation matrix of the bulkhead coordinate system b to the mechanical arm coordinate system r data is constructed , which is:

[0048] ;

[0049] .

[0050] Preferably, the rotation matrix of the mechanical arm coordinate system r to the bulkhead coordinate system b , specifically:

[0051] ; Its inverse matrix

[0052] , specifically:

[0053] ;

[0054] RPY zero point angle calibration of the gyro.

[0055] Compared with the prior art, the embodiment of the application has at least one of the following beneficial effects:

[0056] The bulkhead line marking robot line marking operation calibration method in the embodiment of the application quantitatively calculates the laser tracker coordinate system s , the bulkhead coordinate system b and the mechanical arm coordinate system r ​​​The homogeneous transformation relationship matrix between the two coordinate systems is determined, the conversion process of the planning motion data of the robot from the data specified in the drawing to the specific application data in the field is sorted out, and accurate line marking station guide data and line marking point guide data are provided for the LNG bulkhead line marking robot in wall operation. The laser tracker directly guides the robot to carry out line marking operation, which not only saves human resources and improves the line marking efficiency, but also ensures the stability and uniformity of the line marking quality, and effectively avoids the cumulative error caused by human factors. BRIEF DESCRIPTION OF DRAWINGS

[0057] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings:

[0058] Figure 1 The calibration method flow chart for the line marking operation of the bulkhead line marking robot in an embodiment of the present application;

[0059] Figure 2 The reference bulkhead coordinate system in a preferred embodiment of the present application Point position;

[0060] Figure 3 The schematic diagram of the position of the reference measurement point on the robot used in a preferred embodiment of the present application Point position;

[0061] Figure 4 The schematic diagram of the position of the reference measurement point on the robot used in a preferred embodiment of the present application , The schematic diagram of the position of the reference measurement point on the robot used in a preferred embodiment of the present application. DETAILED DESCRIPTION

[0062] The present application will be described in detail below with specific embodiments. The following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be pointed out that, for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made. These all belong to the protection scope of the present application.

[0063] In view of the deficiencies of the prior art, the present application combines laser tracker, high-precision gyroscope and high-precision mechanical arm encoder data, and realizes the accurate positioning of the bulkhead adsorption type line marking robot in three-dimensional space through data fusion solving technology. Based on the above inventive concept, in an embodiment, a calibration method for line marking operation of a bulkhead line marking robot is provided, as shown in Figure 1 The main steps are as follows:

[0064] Step 1, install the laser tracker on the ship wall to be marked, set the line marking robot on the ship wall to be marked, and install the gyroscope on the line marking robot; ​

[0065] Step 2, calibrate the coordinate system of the laser tracker s Transformation relationship to bulkhead coordinate system b ;

[0066] Step 3, based on the transformation relationship Obtain the coordinate system from bulkhead coordinate system b to the robotic arm coordinate system. r The ZYX Euler angle variation relationship was determined, and the gyroscope zero point was calibrated.

[0067] Step 4, based on the transformation relationship The position coordinates of the origin of the marking robot in the bulkhead coordinate system b are measured in real time. Based on the position coordinates of the origin, the marking robot is guided to the target work station.

[0068] Step 5: After the marking robot reaches the workstation, the coordinates of the robot within the robotic arm coordinate system at that workstation are calculated by combining the real-time measured origin position and gyroscope zero point of the marking robot. r Motion control trajectory Complete the marking and calibration task for a single station.

[0069] In the above embodiment, a laser tracker is used to directly guide a wall-mounted scribing robot to perform scribing operations on the inner hull of the bulkhead. This method not only saves manpower and improves scribing efficiency, but also ensures the stability and consistency of scribing quality through robotic scribing, effectively avoiding cumulative errors caused by human factors.

[0070] In one specific embodiment of the present invention, the robot used is a magnetic wheel type. AGV Equipped SCARA A composite robot with a robotic arm. For example... Figure 2 As shown, the gyroscope is mounted on the magnetically driven AGV, and the marking task is performed by a SCARA-type robotic arm. The laser tracker is mounted on the bulkhead of the compartment to be marked.

[0071] To better calibrate the laser tracker coordinate system, a preferred embodiment of the present invention provides a preferred calibration scheme. In step 2, the laser tracker coordinate system is calibrated. s Transformation relationship to bulkhead coordinate system b The specific process is as follows:

[0072] Step 2.1: Before starting the line marking task, collect three known coordinate points on the bulkhead coordinate system (the origin of the coordinate system). The position of the end of the X-axis of the coordinate system The position of the end of the Y-axis of the coordinate system ), for the bulkhead coordinate system b Calibration is performed. Then, the reference point of the bulkhead coordinate system is obtained by measuring with a laser tracker within the laser tracker coordinate system. s3D coordinate information in the coordinate system: origin of the coordinate system The position of the end of the X-axis of the coordinate system The position of the end of the Y-axis of the coordinate system .

[0073] The X and Y axis vectors of the bulkhead reference are calculated based on the three-point coordinates. :

[0074] ;

[0075] ;

[0076] Step 2.2: Through The cross product of vectors yields a result perpendicular to the vector. vector , and then through The cross product of vectors yields a result perpendicular to the vector. vector ,at this time Let them be three mutually orthogonal vectors.

[0077] ;

[0078] ;

[0079] Step 2.3: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require Three vectors, when normalized, can form a unitary matrix. . That is, representing the coordinate system from the bulkhead b Transform the data to the laser tracker coordinate system s The rotated portion of the data that needs to be transformed. Correspondingly, transpose matrix Characterizable from the laser tracker coordinate system s Data to bulkhead coordinate system b The rotated portion of the data.

[0080] ;

[0081] Step 2.4: Next, consider the translation part of the coordinate transformation. After rotation and translation, the origin of the bulkhead in the laser tracker coordinate system... The location data in the bulkhead coordinate system should be: Therefore, from the coordinate system of the laser tracker... s Data to bulkhead coordinate system b Translation vector under data This allows for the construction of measurement data for any laser tracker. s To the bulkhead coordinate system b Homogeneous transformation matrix of measurement data for:

[0082] ;

[0083] ;

[0084] The above embodiment completes the conversion calibration of the laser instrument coordinate system to the cabin wall coordinate system. Further, the conversion calibration of the mechanical arm coordinate to the cabin wall coordinate system is also needed. In a preferred embodiment of the present application, a preferred scheme of step 3 is provided, and the specific process is as follows:

[0085] S3.1: Collect three robot direction angle indication points on the robot mechanical arm , as shown in Figure 3 and Figure 4 , wherein: is the origin of the robot mechanical arm coordinate system, and The measurement needs to be realized by rotating the mechanical arm large arm. When the corresponding angle of the mechanical arm large arm encoder is 0 degrees, the measurement point on the mechanical arm is , and when the corresponding angle of the mechanical arm large arm encoder is 90 degrees, the measurement point on the mechanical arm is . The direction angle indication points constitute a vector , and the direction of the SCARA axis coordinate system of the cabin wall coordinate system is the same as that of the X, Y axis coordinate system of the robot body coordinate system.

[0086] The homogeneous transformation matrix obtained in step 2 can map the vector from the tracking instrument coordinate system s to the cabin wall coordinate system b .

[0087] ;

[0088] Step 3.2: The vector can represent the spatial orientation of the mechanical arm coordinate system b in the cabin wall coordinate system r . Similarly, the cross product can be calculated to obtain the b axis orientation direction of the mechanical arm coordinate system r in the cabin wall coordinate system Z . The three base coordinate system directions of the mechanical arm can be constructed to obtain the calibration rotation matrix of the mechanical arm coordinate system r in the cabin wall coordinate system :

[0089] ;

[0090] Step 3.3: Through the rotation matrix The coordinate system of the robotic arm in the current state can be solved according to... ZYX The three Euler angles of the decomposition :

[0091] ;

[0092] ;

[0093] ;

[0094] In the above formulas, the subscripts express rotation matrix The element in the third row and second column.

[0095] Step 3.4: From three rotation angles It can calibrate the gyroscope mounted on the robot, and adjust the gyroscope's... RPY The zero-point angles are respectively calibrated as .

[0096] During its movement, the robot needs to obtain its real-time position in order to better calculate the next working path. In another preferred embodiment of the invention, a preferred solution for step 4 is provided, which achieves navigation by resolving the robot's center position. The specific process is as follows:

[0097] Step 4.1: Adjust the laser tracker so that it always locks onto the laser tracker reflector sphere located at the origin of the robotic arm. Obtain the spatial position of the robotic arm origin in the laser tracker coordinate system s through real-time feedback from the laser tracker. The origin position of the robotic arm can be determined using the homogeneous transformation matrix in step 2. From the tracker coordinate system s Mapped to bulkhead coordinate system b The above provides a representation of the robotic arm's origin position in the bulkhead coordinate system. :

[0098] ;

[0099] Step 4.2: Based on the real-time robot position, short-distance inertial navigation can be performed using gyroscope information to complete the robot navigation control task and drive the robot to the designated work station.

[0100] Once the robot navigates to the designated station, it begins the line-drawing process. To achieve precise line drawing, a preferred embodiment of the present invention provides a preferred solution for step 5, the specific process of which is as follows:

[0101] Step 5.1: Directly from the gyroscope RPY Solve the coordinate system from the robotic arm coordinate system r to the bulkhead coordinate system.Rotation matrix of b , and its inverse matrix .

[0102] ;

[0103] ;

[0104] Step 5.2: Collect the mechanical arm origin position and convert to the bulkhead coordinate system to get the representation of the robot origin position in the bulkhead coordinate system :

[0105] ;

[0106] Step 5.3: Based on the inverse matrix of step 5.1 and the of step 4.2, get the translation vector of the bulkhead coordinate system b data to the mechanical arm coordinate system r data as .

[0107] Step 5.4: Construct the homogeneous transformation matrix of the bulkhead coordinate system b to the mechanical arm coordinate system r amount data is:

[0108] ;

[0109] ;

[0110] Step 5.5: Line target data are recorded in the bulkhead coordinate system b , at this time all line trajectory planning points can be calculated to the mechanical arm coordinate system r , recorded as :

[0111] ;

[0112] So far, all the LNG bulkhead line marking calibration procedures have been completed, and the mechanical arm lower computer can complete the line marking task according to the trajectory control target in turn after receiving the line trajectory based on its own coordinate system r . Further, after the task of the workstation is completed, the line marking robot is guided to the next workstation to start new line marking work.

[0113]

[0114] ​The above embodiment combs the method for accurately solving the robot position data and the end trajectory control data by laser tracker through data fusion of various sensors. A method basis is provided for cabin wall robot line marking, and a feasible process construction process is determined.

[0115] The specific embodiments of the present application are described above. It needs to be understood that the present application is not limited to the above specific embodiments, and various modifications or changes can be made by those skilled in the art within the scope of the claims, which does not affect the essential content of the present application. The above preferred features can be used in combination as long as they are not in conflict with each other.

Claims

1. A bulkhead scribe robot scribe operation calibration method, characterized by, Comprising: installing a laser tracker on a to-be-linings bulkhead, setting a lining robot on the to-be-linings bulkhead, and installing a gyroscope on the lining robot; Calibrating a laser tracker coordinate system s Conversion relationship to bulkhead coordinate system b ; Based on the conversion relationship , obtain the ZYX Euler angle change relationship of the bulkhead coordinate system b to the mechanical arm coordinate system of the line marking robot r , and calibrate the zero point of the gyroscope; based on the conversion relationship , real-time measuring the position coordinates of the origin of the line marking robot in the bulkhead coordinate system b, based on the position coordinates, guiding the line marking robot to reach a target work station position; After the marking robot reaches the workstation, it calculates the robot's position within the robotic arm coordinate system at that workstation by combining the real-time measured origin position and the gyroscope's zero point. r Motion control trajectory Complete the marking and calibration task for a single station location, specifically: measuring the coordinates of the origin of the robot in real time by the laser tracker and converting them to the robot coordinate system r; The homogeneous transformation matrix from the cabin wall coordinate system to the mechanical arm coordinate system r is obtained in combination with the mechanical arm origin position converted to the mechanical arm coordinate system r and the gyro zero point angle information b to the mechanical arm coordinate system r r ; combining the recorded lineation target data in the cabin wall coordinate system b , based on the homogeneous transformation matrix solving the lineation trajectory of the mechanical arm in the mechanical arm coordinate system r ;​​ The robot arm follows the resulting scribe trajectory The scribe task is performed.

2. The method of claim 1, wherein, The calibrated laser tracker coordinate system s The conversion relationship to the bulkhead coordinate system b , comprising: The origin is selected on the bulkhead coordinate system b, X the most marginal point on the axis, Y the most marginal point on the axis; The laser tracker measures the sphere placed on the bulkhead at the origin point, the... X The outermost point on the axis, the Y The coordinate system of the laser tracker is obtained by measuring the coordinates of the three points on the measuring sphere at the outermost edge point on the axis. s The bulkhead in X axis, Y Axis vectors and origin coordinates; through the laser tracker coordinate system s in the bulkhead X axis, Y axial vector solving the bulkhead Z axis vector and correcting Y axial vector with the assurance X, Y, Z three axial vectors are orthogonal; by two mutually orthogonal X, Y, Z axial vectors resolve the rotation matrix between the bulkhead coordinate system b and the laser tracker coordinate system s and ;​ The translation vector between the bulkhead coordinate system b and the laser tracker coordinate system is calculated by combining the rotation matrix and the bulkhead coordinate system b origin coordinates s ;​ based on the translation transformation vector and the rotation matrix , , obtaining a homogeneous transformation matrix of the laser tracker coordinate system to the bulkhead coordinate system .

3. The method of claim 2, wherein, the cabin wall in the laser tracker coordinate system s X Y Y X, Y, Z the three axis vectors are orthogonal​​​​ By X the axis, Y the axial vector the cross product of the vectors perpendicular to : ; By The cross product of vectors yields a vector perpendicular to : .​ 4. The method of claim 3, wherein, The rotation matrix between the cabin coordinate system b and the laser tracker coordinate system is calculated by two pairs of orthogonal X, Y, Z axial vectors s and , comprising:​ orthonormal X, Y, Z axis vectors normalization, obtaining a rotation matrix with , comprising: 。 5. The method of claim 1, wherein, The conversion relationship is based on the transformation relationship , obtaining the ZYX Euler angle change relationship of the bulkhead coordinate system b to the mechanical arm coordinate system of the line marking robot r , and calibrating the zero point of the gyroscope, comprising: acquiring, by the laser tracker, a reference point on the marking robot X axis, Y reference point, and mapping, by the conversion relationship to the bulkhead coordinate system b above; The reference indicating point data of the X axis, the Y axis and the origin of the mechanical arm coordinate system are collected to solve the calibration rotation matrix of the mechanical arm coordinate system in the cabin wall coordinate system r The calibration rotation matrix of the mechanical arm coordinate system in the cabin wall coordinate system b ;​ by the rotation matrix ZYX way cutting machine robot Euler angles; calibrating the zero points of the three-axis rotation angles of the robot gyroscope by the Euler angles.

6. The method of claim 5, wherein, said by said rotation matrix A ZYX way of slicing robot Euler angles, comprising: ； ； ； denotes the rotation matrix the element in the i-th row and j-th column.

7. The method of claim 6, wherein, The measuring of the coordinates of the origin of the robot in real time by the laser tracker and the converting of them to the robot coordinate system r are specifically: Collecting the mechanical arm origin position by laser tracker ; based on the conversion relationship , obtaining a representation of the robot origin position in the bulkhead coordinate system ; 。 8. The method of claim 7, wherein, The combination converts the mechanical arm origin position in the mechanical arm coordinate system r and the gyro zero point angle information to obtain the homogeneous transformation matrix of the bulkhead coordinate system to the mechanical arm coordinate system b r , comprising:​​ by the zero point angle solving a rotation matrix of the robot coordinate system r to the bulkhead coordinate system b with its inverse matrix ;​ Computing the cabin wall coordinate system b The translation vector of data to the robot coordinate system rdata is ; Constructing a cabin wall coordinate system b A homogeneous transformation matrix of the data to the robot arm coordinate system r , ； 。 9. The method of claim 8, wherein, The rotation matrix of the mechanical arm coordinate system r to the bulkhead coordinate system b Specifically,​ ； the inverse matrix thereof in particular: ； RPY zero angle calibration of the gyroscope, respectively.

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