CN111274696A - Method for acquiring spatial position and attitude of double triangular drill arms of drill jumbo in real time - Google Patents

Abstract

The invention discloses a method for acquiring the spatial position and posture of a double-triangular drill boom of a drill jumbo in real time. And (3) establishing a kinematic equation of the double-triangular drill boom according to the CFDH method, and comparing the simulation result of the virtual prototype with the kinematic equation to verify the correctness of the kinematic equation so as to obtain the accurate position posture of the double-triangular drill boom of the drill boom at any moment. The invention provides reliable guarantee for accurate drilling positioning of the double-triangular drill arm.

Description

Method for acquiring spatial position and attitude of double triangular drill arms of drill jumbo in real time

Technical Field

The invention relates to a positioning technology of a drill boom of a computer drill jumbo, in particular to a method for acquiring the spatial position posture of a double-triangular drill boom of the drill jumbo in real time.

Background

In the process of tunnel and mine exploitation, a full-hydraulic rock drilling trolley is generally used for drilling holes, and the accurate positioning of the drilling hole position is the key of the whole rock drilling hole construction. The positioning of the hole is realized by the movement of the drill arm controlled by the manipulator on the operation table. However, the working environment of the rock drilling machine is complex, dust and water vapor are more in the tunnel, and the driller is far away from the fracture surface, so that the hole positioning is inaccurate, the efficiency is low, and the deviation is large, thereby seriously affecting the blasting effect. In order to overcome the defect of manual positioning, the computer drilling trolley can acquire the three-dimensional space coordinate and the posture of the drill boom in real time, realize accurate auxiliary positioning and hole alignment, gradually replace the traditional full-hydraulic drilling trolley and quickly become mainstream mechanical equipment for tunnel construction. The double-triangular drill boom has the advantages of parallel movement in space, rapid action, compact structure and better stability, but is not easy to control, and the positioning precision is an important factor influencing the operation of the drill boom, so how to realize accurate control on the movement track of the drill boom has direct influence on whether the tail end of the drill boom and a fiber rod can be accurately positioned for drilling.

Disclosure of Invention

The invention aims to provide a method for acquiring the spatial position and the attitude of a double-triangular drill boom of a drill jumbo in real time, which can assist a drill rod to accurately align to a drilling position by accurately acquiring the spatial position and the attitude of the double-triangular drill boom.

In order to achieve the purpose, the method for acquiring the spatial position and the attitude of the front and rear double-triangular drill booms in real time comprises the steps of establishing a three-dimensional model of the double-triangular drill booms, then establishing a virtual prototype, and performing kinematic simulation on the double-triangular drill booms; establishing a kinematic equation of the double-triangular drill boom according to a CDFH method, and comparing a simulation result of a virtual prototype with the kinematic equation to verify the correctness of the kinematic equation so as to obtain the accurate position posture of the double-triangular drill boom of the drill boom at any moment; the method comprises the following steps:

step (ii) of1, obtaining a verification Point p_iThree-dimensional space measurement coordinates relative to the frame coordinate system {0}⁰p_{i_C}；

Step 2, establishing a coordinate system of the double-triangular drilling arm i equal to 1 based on an improved CFDH method;

step 3, establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems;

step 4, obtaining a verification point p_iThe coordinates are calculated in three-dimensional space.

Further, in step 1, a verification point p is obtained_iMeasuring coordinates in three-dimensional space relative to a frame coordinate system {0}⁰p_{i_C}The specific method comprises the following steps:

step 1.1, establishing a three-dimensional entity model, importing the three-dimensional entity model into software and establishing a virtual prototype;

step 1.2, arranging angle and length sensors; the double-triangular drill arm is provided with 11 joints, wherein 8 joints are rotating joints, 3 joints are moving joints, and an angle sensor and a length sensor are respectively arranged on the 11 joints;

step 1.3, obtaining point p in virtual prototype_iSpatial position coordinates; the method comprises the following steps:

① is set in the virtual prototype, and the sensor theta is set₁，θ₂，θ₃，θ₄，d₅，θ₆，θ₇，θ₈，θ₉，d₁₀，d₁₁Set to a value within any reasonable range. Driving the virtual prototype model to a set value of a sensor;

② Point p_1c，p_2c，p_3c，p_4c，p_5c，p_6c，p_7c，p_8c，p_9c，p_10c，p_11cRespectively at any point on the joint connecting rods 1-11, and measuring the three-dimensional space measurement coordinates of the points in the virtual prototype to obtain p_ic＝{x_{i_c}，y_{i_c}，z_{i_c}}。

Further, in step 2, a specific method for establishing a coordinate system with drill boom i equal to 1 is as follows:

step 2.1, find outA common perpendicular line between the joint axes i and i +1 or the intersection point of the joint axes i and i +1, and the intersection point of the joint axes i and i +1 is taken as an origin O of the drill boom coordinate system { i }_i；

Step 2.2, specifying the orientation Z along the joint axis i_i；

Step 2.3, a common perpendicular line from the axis i to i +1 is defined, and if the joint axis i and the joint axis i +1 intersect, X is defined_iThe axis is perpendicular to the plane of the joint axes i and i +1, and X is determined_i；

Step 2.4, determining Y according to the right-hand rule_i；

Step 2.5, repeating the steps 2.1-2.4, and establishing a coordinate system { X }_i，Y_i，Z_i，O_i}。

Further, in step 3, a specific method for establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems is as follows:

step 3.1, defining parameters of adjacent drill boom joints, wherein the parameters are a_i-1,α_i-1,d_i,θ_i；a_i-1: length of connecting rod along X_i-1Axis from Z_i-1Move to Z_iα_i-1: angle of rotation of connecting rod being around X_i-1Axis from Z_i-1Rotate to Z_iThe angle of (d); d_i: offset of connecting rod in Z direction_iAxis from X_i-1Move to X_iThe distance of (d); theta_i: angle of articulation about Z_iAxis from X_i-1Rotated to X_iThe angle of (d);

step 3.2, defining a homogeneous coordinate transformation matrix of adjacent joint coordinate systems;

① winding coordinate system i-1 around X_i-1Shaft rotation α_i-1Angle, Z_i-1Axis and Z_iThe axes are parallel to obtain a rotation matrix R_X(α_i-1)。

② locating the coordinate system i-1 along the current X_i-1Translation distance a_i-1Let Z be_i-1Axis and Z_iThe axes coincideTo obtain a translation matrix D_X(α_i-1)。

Winding the coordinate system i-1 around the current Z_iAxis of rotation theta_iAngle, X_i-1Axis and X_iThe axes are parallel to obtain a translation matrix D_Z(d_i)。

③ along Z_iDistance d of shaft translation_iThe coordinate system { i-1} is completely overlapped with the coordinate system { i }.

3.3, establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems; multiplying the four matrixes in the step 3.2 by the four matrixes to obtain a homogeneous transformation matrix of the coordinate system { i } relative to the coordinate system { i-1 }:

further, in step 4, a verification point p is obtained_iThe specific method for calculating the coordinates in the three-dimensional space comprises the following steps:

step 4.1, homogeneous transformation matrix of coordinate system { i } relative to coordinate system {0} is

Step 4.2, Point p in coordinate System { i }_iHas local coordinates ofⁱp_iThen point p_iThree-dimensional space coordinates relative to the frame coordinate system {0} of

Step 4.3, checking the point p_iThree-dimensional space of (2) calculating coordinates⁰p_{i_J}And measuring coordinates in three-dimensional space in virtual prototype⁰p_{i_C}Whether they are equal; if they are equal, the parameter a of the joint point i is described_i-1,α_i-1,d_i,θ_iSelecting and converting the matrix and the like correctly, setting i as i +1, repeating the step 2, the step 3 and the step 4, and obtaining the parameters of the joint point i +1 and the conversion matrix; if they are not equal, the parameter a of the joint point i is described_i-1,α_i-1,d_i,θ_iSelecting error, and re-measuring the parameters in the virtual prototype until the error is detected⁰p_{i_J}＝⁰p_{i_C}。

The invention has the beneficial effects that: by establishing a virtual prototype, 11 joints are arranged on the double-triangular drill boom, and the spatial position postures of any point and any moment of each joint on the drill boom are determined by a CFDH method and homogeneous coordinates, and the accurate position postures provide important support for the accurate positioning of the fiber rod.

Drawings

FIG. 1 is a flow chart of the operation of the present invention;

FIG. 2 is a virtual prototype of the present invention;

FIG. 3 is a schematic view of the angle and length sensor arrangement of the present invention;

FIG. 4 shows point p of the present invention_iA schematic diagram of measured coordinates of spatial locations;

FIG. 5 is a schematic diagram of a space coordinate system of a drill boom based on a CFDH method according to the present invention;

FIG. 6 is a schematic diagram of coordinates of two adjacent joints;

in the figure, 1-wing type arm base I, 2-wing type arm base II, 3-rear arm cross hinge, 4-drill arm telescopic cylinder barrel, 5-drill arm telescopic cylinder rod, 6-front arm cross hinge, 7-rotary cylinder barrel, 8-rotary cylinder rod, 9-propeller swinging cylinder, 10-propeller compensation cylinder and 11-drilling machine propelling cylinder.

Detailed Description

The invention is described in further detail below with reference to the figures and the embodiments.

The double-triangular drill boom is similar to a multi-joint robot structure, so that the kinematics of the drill boom can be analyzed by using a common theory in robot research, and a method adopted by the analysis is a CFDH (coordinated fixed Denavit-Hartenberg) method, so that the method not only improves the accuracy and operability of the kinematics analysis, but also saves the analysis time and provides an effective means for establishing a kinematics equation. The homogeneous matrix change is suitable for describing the transformation relation among a plurality of coordinates due to the intuitive geometrical significance of the homogeneous matrix change. Furthermore, homogeneous matrix changes can also represent the transformation of rotation and displacement by using the same matrix, and the characteristic makes the homogeneous matrix change widely used in the kinematics research of multi-joint robots.

The method comprises the steps of firstly, carrying out three-dimensional modeling on parts on the double-triangular drill boom by using Pro/E software, assembling all established part models according to actual installation requirements to further obtain a three-dimensional model of the double-triangular drill boom, then introducing the three-dimensional model of the double-triangular drill boom into ADMAS software, obtaining a virtual prototype of the drill boom through corresponding processing, and simulating the drill boom. And (3) establishing a coordinate system of the double-triangular drill boom by using a CFDH method, and then establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems to obtain a kinematic equation of the double-triangular drill boom. And (3) verifying the kinematic equation by using virtual prototype simulation, and if the kinematic equation passes the verification, obtaining the coordinate value of the real-time position posture of the double-triangular drill arm accurately. FIG. 1 is a flow chart of the method. The method for acquiring the spatial position attitude of the double triangular drill booms of the drill jumbo in real time comprises the following steps: step 1, obtaining verification point p_iMeasured coordinates in three-dimensional space relative to the frame coordinate system {0}⁰p_{i_C}。

Step 1.1, establishing a three-dimensional entity model, importing the three-dimensional entity model into software to establish a virtual prototype, and displaying the virtual prototype in a figure 2.

The computer drill jumbo drill boom is a direct positioning double-triangular drill boom, has 8 rotating joints and 3 moving joints, and is a joint type drill boom with multiple degrees of freedom. Respectively is a wing type arm seat I1, a wing type arm seat II2, a rear arm cross hinge 3, a drill arm telescopic cylinder barrel 4, a drill arm telescopic cylinder rod 5, a front arm cross hinge 6, a rotary cylinder barrel 7, a rotary cylinder rod 8, a propeller swinging cylinder 9, a propeller compensating cylinder 10 and a drilling machine propelling cylinder 11.

Step 1.2, arranging angle and length sensors, as shown in figure 3. The eleven sensors are respectively:

r1: an angle sensor 1 for measuring the lifting angle theta of the wing-type arm seat I₁。

R2: an angle sensor 2 for measuring the lifting angle theta of the wing type arm seat II₂. Remarking: the sensor is not installed in a real object, the angle of the sensor is ensured by a parallel four-bar linkage mechanism of the wing type arm, and the angle is a negative value of the sequence 1 angle. The sensor is installed in the virtual prototype.

R3: an angle sensor 3 for measuring the left-right swing angle theta of the boom₃。

R4: an angle sensor 4 for measuring the up-down lifting angle theta of the big arm₄。

R5: a length sensor 5 for measuring the fore-and-aft telescopic length d of the boom₅。

R6: an angle sensor 6 for measuring the vertical lifting angle theta of the propeller₆。

R7: an angle sensor 7 for measuring the left-right swing angle theta of the propeller₇。

R8: an angle sensor 8 for measuring a propeller rotation angle θ₈。

R9: an angle sensor 9 for measuring a propeller pitch angle theta₉。

R10: a length sensor 10 for measuring the extension length d of the propeller₁₀。

R11: a length sensor 11 for measuring the telescopic length d of the rock drill₁₁。

Step 1.3, obtaining point p in virtual prototype_iSpatial position coordinates.

① is set in the virtual prototype, and the sensor theta is set₁，θ₂，θ₃，θ₄，d₅，θ₆，θ₇，θ₈，θ₉，d₁₀，d₁₁Set to a value within any reasonable range. The virtual prototype model is driven to the sensor settings.

② Point p_1c，p_2c，p_3c，p_4c，p_5c，p_6c，p_7c，p_8c，p_9c，p_10c，p_11cRespectively at any point on the joint connecting rods 1-11, and measuring the three-dimensional space measurement coordinates of the points in the virtual prototype to obtain p_ic＝{x_{i_c}，y_{i_c}，z_{i_c}As shown in fig. 4.

And 2, establishing a drill boom i-1 coordinate system based on an improved CFDH method.

Step 2.1, finding out a common perpendicular line between the joint axes i and i +1 or an intersection point of the joint axes and i +1, and taking the intersection point of the joint axes i and i +1 as an origin O of a drill boom coordinate system { i }, wherein_i。

Step 2.2, specifying the orientation Z along the joint axis i_i。

Step 2.3, a common perpendicular line from the axis i to i +1 is defined, and if the joint axis i and the joint axis i +1 intersect, X is defined_iThe axis is perpendicular to the plane of the joint axes i and i +1, and X is determined_i。

Step 2.4, determining Y according to the right-hand rule_iWherein i is 0,1,2,3,4,5,6,7,8,9,10, 11.

Repeating the steps 2.1-2.4, and establishing a coordinate system { X }_i，Y_i，Z_i，O_iAnd (6) establishing a space coordinate system shown in the attached figure 4. And 3, establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems.

Step 3.1, defining parameters of adjacent drill boom joints, wherein the parameters are a_i-1,α_i-1,d_i,θ_iSee fig. 6.

a_i-1: length of connecting rod along X_i-1Axis from Z_i-1Move to Z_iThe distance of (d);

α_i-1: angle of rotation of connecting rod being around X_i-1Axis from Z_i-1Rotate to Z_iThe angle of (d);

d_i: offset of connecting rod in Z direction_iAxis from X_i-1Move to X_iThe distance of (d);

θ_i: angle of articulation about Z_iAxis from X_i-1Rotated to X_iThe angle of (d);

step 3.2, defining homogeneous coordinate transformation matrix of adjacent joint coordinate systems

① winding coordinate system i-1 around X_i-1Shaft rotation α_i-1Angle, Z_i-1Axis and Z_iThe axes are parallel to obtain a rotation matrix R_X(α_i-1)。

② locating the coordinate system i-1 along the current X_i-1Translation distance a_i-1Let Z be_i-1Axis and Z_iThe axes are superposed to obtain a translation matrix D_X(α_i-1)。

Winding the coordinate system i-1 around the current Z_iAxis of rotation theta_iAngle, X_i-1Axis and X_iThe axes are parallel to obtain a translation matrix D_Z(d_i)。

Along Z_iDistance d of shaft translation_iThe coordinate system { i-1} is completely overlapped with the coordinate system { i }.

And 3.3, establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems. Multiplying the four matrices by this may result in a homogeneous transformation matrix for coordinate system { i } relative to coordinate system { i-1 }:

in the above formula, c represents cos and s represents sin.

Step 4, obtaining a verification point p_iThe coordinates are calculated in three-dimensional space.

Step 4.1, homogeneous transformation matrix of coordinate system { i } relative to coordinate system {0} is

Step 4.2, Point p in coordinate System { i }_iHas local coordinates ofⁱp_iThen point p_iThree-dimensional space coordinates relative to the frame coordinate system {0} of

Step 4.3, checking the point p_iThree-dimensional space of (2) calculating coordinates⁰p_{i_J}And measuring coordinates in three-dimensional space in virtual prototype⁰p_{i_C}Whether or not equal.

①, equal, indicate the parameter a of the joint point i_i-1,α_i-1,d_i,θ_iThe selection, transformation matrix, etc. are correct.

Setting i as i +1, repeating the step 2, the step 3 and the step 4, and obtaining parameters and transformation matrixes of the joint points i + 1.

② if they are not equal, the parameter a of the joint point i is described_i-1,α_i-1,d_i,θ_iSelecting error, and re-measuring the parameters in the virtual prototype until the error is detected⁰p_{i_J}＝⁰p_{i_C}。

And 5, acquiring joint parameters of the drill boom model.

Step 5.1, after step 4 has been performed, four parameters of the joints 1-11 are obtained which are verified as correct, as followsShown in table 1. d₂，d₃，d₇，d₈，d₉，d₁₁，a₂，a₃，a₄，a₇，a₉，a₁₁Is a known quantity, is determined by the inherent geometrical parameters of the drill boom in step 4. Theta₁，θ₃，θ₄，d₅，θ₆，θ₇，θ₈，θ₉，d₁₀The input quantity is measured by each sensor in step 1.

Step 5.2, according to the table, homogeneous transformation matrix between adjacent joint coordinate systems of the mechanical armIn this example, the following is:

step 5.3, for any point on any part of the drill boomⁱp_iSpatial attitude at any time⁰p_iComprises the following steps:

wherein

From step 5.2.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited thereto, and various changes which can be made within the knowledge of those skilled in the art without departing from the gist of the present invention are within the scope of the claims of the present invention.

Claims (5)

1. A method for acquiring the spatial position and attitude of a double-triangular drill boom of a drill jumbo in real time is characterized by comprising the following steps of: the method comprises the steps of establishing a three-dimensional model of the double-triangular drill boom, then establishing a virtual prototype, and performing kinematic simulation on the double-triangular drill boom; establishing a kinematic equation of the double-triangular drill boom according to a CFDH method, and comparing a simulation result of a virtual prototype with the kinematic equation to verify the correctness of the kinematic equation so as to obtain the accurate position posture of the double-triangular drill boom of the drill boom at any moment; the method comprises the following steps:

step 1, obtaining a verification point p_iThree-dimensional space measurement coordinates relative to the frame coordinate system {0}⁰p_{i_C}；

Step 2, establishing a coordinate system of the double-triangular drilling arm i equal to 1 based on an improved CFDH method;

step 3, establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems;

step 4, obtaining a verification point p_iThe coordinates are calculated in three-dimensional space.

2. A method of obtaining in real time attitude of spatial positions of dual-gimbals of a rock drilling rig as claimed in claim 1, characterized by: in step 1, a verification point p is obtained_iMeasuring coordinates in three-dimensional space relative to a frame coordinate system {0}⁰p_{i_C}The specific method comprises the following steps:

step 1.1, establishing a three-dimensional entity model of a double-triangular drill arm, and importing the three-dimensional entity model into software to establish a virtual prototype;

step 1.2, arranging angle and length sensors: the double-triangular drill arm is provided with 11 joints, wherein 8 joints are rotating joints, 3 joints are moving joints, and an angle sensor and a length sensor are respectively arranged on the 11 joints;

step 1.3, obtaining point p in virtual prototype_iSpatial position coordinates; the method comprises the following steps:

① in the virtual prototype, the angle and displacement of the sensor in step 1.2 are measured

θ₁,θ₂,θ₃,θ₄,d₅,θ₆,θ₇,θ₈,θ₉,d₁₀,d₁₁Setting the value in any reasonable range, and driving the virtual prototype model to the set value of the sensor;

② Point p_1c,p_2c,p_3c,p_4c,p_5c,p_6c,p_7c,p_8c,p_9c,p_10c,p_11cRespectively at any point on the joint connecting rods 1-11, and measuring the three-dimensional space measurement coordinates of the points in the virtual prototype to obtain p_ic＝{x_{i_c,}y_{i_c,}z_{i_c}}。

3. A method of obtaining in real time attitude of spatial positions of dual-gimbals of a rock drilling rig as claimed in claim 1, characterized by: in step 2, a specific method for establishing a coordinate system with drill boom i equal to 1 is as follows:

step 2.1, finding out a common perpendicular line between the joint axes i and i +1 or an intersection point of the joint axes i and i +1, and taking the intersection point of the joint axes i and i +1 as an origin O of a drill boom coordinate system { i }, wherein_i；

Step 2.2, specifying the orientation Z along the joint axis i_i；

Step 2.3, a common perpendicular line from the axis i to i +1 is defined, and if the joint axis i and the joint axis i +1 intersect, X is defined_iThe axis is perpendicular to the plane of the joint axes i and i +1, and X is determined_i；

Step 2.4, determining Y according to the right-hand rule_i；

Step 2.5, repeating the steps 2.1-2.4, and establishing a coordinate system { X }_i,Y_i,Z_i,O_i}。

4. A method of obtaining in real time attitude of spatial positions of dual-gimbals of a rock drilling rig as claimed in claim 1, characterized by: in step 3, the specific method for establishing the homogeneous coordinate transformation matrix of the adjacent joint coordinate system comprises the following steps:

step 3.1, defining the joint parameters of adjacent drill booms, which are respectivelya_i-1,α_i-1,d_i,θ_i；a_i-1: length of connecting rod along X_i-1Axis from Z_i-1Move to Z_iα_i-1: angle of rotation of connecting rod being around X_i-1Axis from Z_i-1Rotate to Z_iThe angle of (d); d_i: offset of connecting rod in Z direction_iAxis from X_i-1Move to X_iThe distance of (d); theta_i: angle of articulation about Z_iAxis from X_i-1Rotated to X_iThe angle of (d);

step 3.2, defining a homogeneous coordinate transformation matrix of adjacent joint coordinate systems;

winding the coordinate system { i-1} around X_i-1Shaft rotation α_i-1Angle, Z_i-1Axis and Z_iThe axes are parallel to obtain a rotation matrix R_X(α_i-1)；

Coordinate system i-1 along current X_i-1Translation distance a_i-1Let Z be_i-1Axis and Z_iThe axes are superposed to obtain a translation matrix D_X(α_i-1)；

Winding the coordinate system i-1 around the current Z_iAxis of rotation theta_iAngle, X_i-1Axis and X_iThe axes are parallel to obtain a translation matrix D_Z(d_i)；

Along Z_iDistance d of shaft translation_iMaking the coordinate system { i-1} completely coincide with the coordinate system { i };

3.3, establishing a homogeneous coordinate transformation matrix of adjacent joint coordinate systems; multiplying the four matrixes in the step 3.2 by the four matrixes to obtain a homogeneous transformation matrix of the coordinate system { i } relative to the coordinate system { i-1 }:

5. a method of obtaining in real time attitude of spatial positions of dual-gimbals of a rock drilling rig as claimed in claim 1, characterized by: in step 4, a verification point p is obtained_iThe specific method for calculating the coordinates in the three-dimensional space comprises the following steps:

step 4.1, homogeneous transformation matrix of coordinate system { i } relative to coordinate system {0} is

Step 4.2, Point p in coordinate System { i }_iHas local coordinates ofⁱp_iThen point p_iThree-dimensional space coordinates relative to the frame coordinate system {0} of⁰p_{i_J}：

Step 4.3, checking the point p_iThree-dimensional space of (2) calculating coordinates⁰p_{i_J}And measuring coordinates in three-dimensional space in virtual prototype⁰p_{i_C}Whether they are equal; if they are equal, the parameter a of the joint point i is described_i-1,α_i-1,d_i,θ_iSelecting and converting the matrix and the like correctly, setting i as i +1, repeating the step 2, the step 3 and the step 4, and obtaining the parameters of the joint point i +1 and the conversion matrix; if they are not equal, the parameter a of the joint point i is described_i-1,α_i-1,d_i,θ_iSelecting error, and re-measuring the parameters in the virtual prototype until the error is detected⁰p_{i_J}＝⁰p_{i_C}。

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