JP2014240116A - Mark-off display device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mark-off display device and method capable of correctly displaying a position to be marked off even in a case where the cylindrical member deforms due to self-weight in performing mark-off in a state that a cylindrical member is placed in a horizontal state.SOLUTION: A mark-off display device 1 for displaying a position B to be marked off to a cylindrical member 100 comprises: a measurement part for measuring an end surface shape of the cylindrical member 100 which is deformed due to self-weight when the cylindrical member 100 is placed in a horizontal state; a calculation part for determining a corrected angle θ' which is corrected according to deformation of the cylindrical member 100 by determining the peripheral length of the cylindrical member 100 and a cylindrical center G, and converting an angle from the cylindrical center G of the cylindrical member 100 into a ratio of the peripheral length; and a display part for displaying the position B to be marked off to the cylindrical member 100 by laser beam L on the basis of the corrected angle θ'.

Description

  The present invention relates to a ruled line display device and a ruled line display method for displaying a position of a ruled line on a cylindrical member.

  Usually, a steel tank (container) has a cylindrical body (cylindrical member). For example, accessories such as nozzles and pins are attached to the body of the tank by welding or the like. For this reason, before attaching an accessory, it is necessary to perform a work called a ruled line for writing the attachment position of the accessory into the body.

  In the conventional ruler work, an operator measures the inner circumference or the outer circumference of the body part with a measure to determine the position of the ruler. However, since such a manual operation lacks accuracy, a method for accurately making a ruled line is desired.

JP 2010-038882 A JP 2011-220816 A JP 2008-157635 A JP 2006-266910 A JP 2003-057191 A

  In view of this, the present inventors propose a method of displaying the position of the ruled line on the cylindrical member using a laser projector. Usually, a laser projector obtains its position three-dimensionally from a plurality of targets whose exact positions are known, and after obtaining the position and distance of markings from its own position, laser irradiation is performed. Draw a line or character of any shape at high speed, and display it as if it were a continuous line.

  By the way, in the case of a large tank, the ruled line work is often performed in a state in which the body portion is placed horizontally due to restrictions of equipment in the factory. However, when the trunk portion is placed horizontally, the trunk portion is deformed by its own weight, and a flat distortion is generated from a perfect circle. In this case, the position of the target is shifted, and the length of the arc per unit angle is different between the horizontal direction and the vertical direction only with a simple angular position assuming a perfect circle. Cannot be displayed accurately. This made it difficult to put a ruled-line display using a laser projector into practical use.

  The present invention has been proposed in view of such a conventional situation, and when a ruler is formed in a state where the cylindrical member is placed horizontally, the position of the ruler is accurately determined even when the cylindrical member is deformed by its own weight. It is an object to provide a ruled line display device and a ruled line display method that can be displayed on the screen.

The present invention provides the following means.
(1) A ruled line display device for displaying a position for marking on a cylindrical member,
A measuring unit for measuring the end surface shape of the cylindrical member deformed by its own weight when the cylindrical member is placed horizontally;
An operation for obtaining the circumferential length and the cylindrical center of the cylindrical member from the end face shape of the cylindrical member, converting the angle from the cylindrical center of the cylindrical member to the ratio of the circumferential length, and obtaining an angle corrected according to the deformation. And
A cylindrical member ruler mark display device comprising: a display unit that displays a position of a ruled mark on the cylindrical member with a laser beam based on the corrected angle.
(2) The measurement unit arranges a plurality of targets side by side on the end face of the cylindrical member, measures the positions of the plurality of targets,
The calculation unit obtains the end surface shape of the cylindrical member as an approximate curve from the position information of the plurality of targets, and obtains the circumference of the cylindrical member and the center of the cylinder by calculation from the approximate curve. ) Is a cylindrical member ruled line display device.
(3) The ruler display device for a cylindrical member according to (2), wherein the measurement unit includes a three-dimensional measuring instrument that measures the position of the target.
(4) Said display part irradiates said laser beam to the end surface of said cylindrical member, or an inner peripheral surface or an outer peripheral surface, and displays a ruled line in the said ruled position, (1)-(characteristics) 3) The ruler display device for cylindrical members according to any one of the above items.
(5) A ruled line display method for displaying a position of a ruled line on a cylindrical member,
A measuring step for measuring an end face shape of the cylindrical member deformed by its own weight when the cylindrical member is placed horizontally;
An operation for obtaining the circumferential length and the cylindrical center of the cylindrical member from the end face shape of the cylindrical member, converting the angle from the cylindrical center of the cylindrical member to the ratio of the circumferential length, and obtaining an angle corrected according to the deformation. Steps,
And a display step of displaying a position to be marked on the cylindrical member with a laser beam based on the corrected angle.
(6) In the measurement step, a plurality of targets are arranged side by side on the end face of the cylindrical member, and the positions of the plurality of targets are measured,
In the calculating step, the end face shape of the cylindrical member is obtained as an approximate curve from the position information of the plurality of targets, and the circumferential length and cylindrical center of the cylindrical member are obtained by calculation from the approximate curve. The method for displaying a ruled sheet of a cylindrical member as described in).
(7) In the measurement step, the position of the target is measured using a three-dimensional measuring instrument, and the ruler display method for cylindrical members according to (6) above,
(8) In the display step, the laser beam is irradiated on an end surface, an inner peripheral surface, or an outer peripheral surface of the cylindrical member, and a ruled line is displayed at the position to be marked. 7) The ruler display method for the cylindrical member according to any one of 7).

  As described above, according to the present invention, a ruled line display device and a ruled line display method capable of accurately displaying the position of a ruled line, even when the cylindrical member is deformed by its own weight when performing a ruled line while the cylindrical member is placed horizontally. Can be provided.

It is a block diagram which shows schematic structure of a laser projector. It is a perspective view which shows the usage type of a laser projector. It is the schematic diagram which represented the shape of the cylindrical member placed horizontally by the approximate curve. It is a flowchart which shows the procedure which calculates | requires the perimeter of a cylindrical member. It is a flowchart which shows the procedure which calculates | requires the cylinder center of a cylindrical member. It is a flowchart which shows the procedure which calculates | requires the cylindrical center of a cylindrical member similarly. It is a flowchart which shows the procedure which calculates | requires the position which scribes. It is a flowchart which shows the procedure which calculates | requires the position which cuts out a ruled line similarly. It is a perspective view which shows the case where a ruled line is displayed on the internal peripheral surface of a cylindrical member. It is a perspective view which shows the case where a ruled line is displayed on the outer peripheral surface of a cylindrical member.

Hereinafter, a ruled-line display method and a ruled-line display device for a cylindrical member to which the present invention is applied will be described in detail with reference to the drawings.
In the drawings used in the following description, in order to make the features easy to understand, there are cases in which the portions that become the features are schematically shown for convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent.

(Ruled line display device)
First, for example, a laser projector 1 shown in FIGS. 1 and 2 will be described as a ruled line display device to which the present invention is applied.
FIG. 1 is a block diagram showing a schematic configuration of the laser projector 1. FIG. 2 is a perspective view showing how the laser projector 1 is used.

  As shown in FIGS. 1 and 2, the laser projector 1 displays a position B for scoring on the cylindrical member 100 with a laser beam L. Specifically, the laser projector 1 includes a measurement unit 2, a calculation unit 3 electrically connected to the measurement unit 2, and a display unit 4 electrically connected to the calculation unit 3. ing. The laser projector 1 is placed in advance at a position where measurement and display can be performed with respect to the horizontally placed cylindrical member 100.

  The measuring unit 2 measures the end face shape of the cylindrical member 100 that is deformed by its own weight when the cylindrical member 100 is placed horizontally. Specifically, the measurement unit 2 measures the positions of the plurality of targets T in a state where the plurality of targets T are arranged on the end surface 100 a of the cylindrical member 100.

  The plurality of targets T are arranged on the same circumference in the end surface 100 a of the cylindrical member 100. In the present embodiment, each target T is disposed so as to be located at the center in the thickness direction of the end surface 100 a of the cylindrical member 100. In addition, about arrangement | positioning of the target T, it is also possible to arrange | position not only in such an arrangement | positioning but in the position along the inner peripheral surface 100b or the outer peripheral surface 100c among the end surfaces 100a of the cylindrical member 100. As for the number of targets T, a sufficient number of targets T may be disposed to measure the shape of the end surface 100a of the cylindrical member 100.

  The measurement unit 2 irradiates the measurement light L ′ to the target T that is a measurement target of the horizontally placed cylindrical member 100 and receives the measurement light L ′ that is reflected and returned from the target T. The position of the target T is measured.

  The computing unit 3 obtains the circumferential length of the cylindrical member 100 and the cylindrical center G from the end surface shape of the cylindrical member 100 measured by the measuring unit 2 using, for example, a computer. Specifically, the calculation unit 3 obtains the shape of the cylindrical member 100 from the position information of the plurality of targets T as the approximate curve C, and obtains the circumference of the cylindrical member 100 and the cylindrical center G from the approximate curve C by calculation. Further, the calculation unit 3 converts the angle from the cylindrical center G of the cylindrical member 100 into a ratio of the circumferential length, and obtains an angle θ ′ corrected in accordance with the deformation of the cylindrical member 100. Note that the angle θ ′ is an angle centered on the cylindrical center G, and is expressed as an angle from the reference targate A to the ruled position B.

  The display unit 4 displays the position B to be marked with the laser beam L using, for example, a semiconductor laser. Specifically, the display unit 4 irradiates the end surface 100 a of the cylindrical member 100 with the laser light L based on the angle θ ′ corrected according to the deformation of the cylindrical member 100. Thereby, the ruled line S is displayed on the end surface 100a of the cylindrical member 100 along the position B where the ruled line is drawn.

  In the laser projector 1 having the above-described configuration, when the ruler is made in a state where the cylindrical member 100 is placed horizontally, even when the cylindrical member 100 is deformed by its own weight, the position B where the ruler is drawn can be accurately displayed. Is possible.

(Ruled line display method)
Next, as a ruled line display method to which the present invention is applied, a case where the laser projector 1 is used to display the position B where the ruled line is placed on the horizontal cylindrical member 100 will be described as an example.

  The ruled line display method to which the present invention is applied includes a measuring step of measuring the end surface shape of the cylindrical member 100 deformed by its own weight when the cylindrical member 100 is placed horizontally, the circumferential length of the cylindrical member 100 from the end surface shape of the cylindrical member 100, and A calculation step of obtaining the cylindrical center G, converting the angle of the cylindrical member 100 from the cylindrical center G into a ratio of the circumference, obtaining an angle θ ′ corrected in accordance with the deformation of the cylindrical member 100, and the corrected angle θ And a display step of displaying a position B on the cylindrical member 100 with a laser beam L.

  Specifically, first, in the measurement step, a plurality of targets T are arranged side by side on the end surface 100 a of the cylindrical member 100, and the positions of the plurality of targets T are measured using the laser projector 1. In the present embodiment, for example, as shown in FIG. 3, 20 targets T <b> 1 to T <b> 20 are arranged at equal intervals in the central portion in the thickness direction of the end surface 100 a of the cylindrical member 100. FIG. 3 is a schematic diagram showing the end face shape of the horizontally placed cylindrical member 100 as an approximate curve C. FIG.

  In the present embodiment, as shown in FIG. 3, the target T3 is set as the reference target A, and the ruled line S is displayed at a position B (xB, yB) that is separated from the reference target A by an angle θ in the counterclockwise direction. Illustrate.

  Note that the angle θ means an angle from the cylindrical center G when the cylindrical member 100 is a perfect circle. On the other hand, as shown in FIG. 3, the angle from the cylinder center G when the horizontally placed cylindrical member 100 is deformed by its own weight is actually the corrected angle θ ′, but in FIG. 3, it corresponds to a perfect circle. It is expressed as an angle θ.

  Next, in the calculation step, the end face shape of the cylindrical member 100 is obtained as an approximate curve C from the position information of the targets T1 to T20, and the circumferential length and the cylindrical center G of the cylindrical member 100 are obtained from the approximate curve C by calculation.

  Specifically, in this embodiment, as shown in FIG. 3, XY coordinates centering on the irradiation position O (x0, y0) of the measurement light L ′ of the laser projector 1 are set, and each of the targets T1 to T20 is set. An approximate curve C to be connected is obtained.

  When obtaining the approximate curve C, the first region E1 from the target T1 (x1, y1) to the target T6 (x2, y2) and the first region E1 from the target T6 (x2, y2) to the target T11 (x3, y3). The second region E2, the third region E3 from the target T11 (x3, y3) to the target T16 (x4, y4), and the fourth region from the target T16 (x4, y4) to the target T1 (x1, y1). Divide into four areas E4.

When the arcs connecting the targets T1 to T6 (T6 to T11, T11 to T16, T16 to T1) of the four divided regions E1 to E4 are expressed by a fifth order polynomial, the following formulas (1) to (4 ).
E1: f ₁ (x) = a ₁ + a ₂ x + a ₃ x ² + a ₄ x ³ + a ₅ x ⁴ + a ₆ x ⁵ (1)
E2: g ₁ (y) = b ₁ + b ₂ y + b ₃ y ² + b ₄ y ³ + b ₅ y ⁴ + b ₆ y ⁵ (2)
E3: f ₂ (x) = c ₁ + c ₂ x + c ₃ x ² + c ₄ x ³ + c ₅ x ⁴ + c ₆ x ⁵ (3)
E4: g ₂ (y) = d ₁ + d ₂ y + d ₃ y ² + d ₄ y ³ + d ₅ y ⁴ + d ₆ y ⁵ (4)

When the four arcs represented by the above formulas (1) to (4) are converted into approximate curves by the least square method, they are represented by the following approximate formulas (1) ′ to (4) ′.
E1: y = f ₁ (x) (1) ′
E2: x = g ₁ (y) (2) ′
E3: y = f ₂ (x) (3) ′
E4: x = g ₂ (y) (4) ′

  Here, the reason why the approximate curve C is divided into four at a position where the X axis and the Y axis do not intersect is to apply the least square method. Further, the approximate expression (1) ′ of the first area E1 and the approximate expression (3) ′ of the third area E3 are expressed by a function y = f (x), and the approximate expression (2) of the second area E2 This is the reason why 'and the approximate expression (4) of the fourth region E4 are expressed by a function of x = g (y).

  When the circumferential length of the approximate curve C of the cylindrical member 100 is LL, the circumferential length LL of the approximate curve C of the cylindrical member 100 can be calculated by the following equation (5). In the present embodiment, the circumferential length LL of the approximate curve C of the cylindrical member 100 is represented by a fifth order polynomial.

When obtaining the circumference LL in the approximate curve C of the cylindrical member 100, the calculation is performed according to the procedure of the flowchart shown in FIG. Incidentally, DF1 shown in FIG. _4, the differential equation _f 1 (x), that is, when _f 1 (x) is a fifth order polynomial, represented by the following formula (6). DG1 shown in FIG. 4 is represented by the following equation (7) when g ₁ (y) is a differential equation, that is, when g ₁ (y) is a quintic polynomial. Also, DF2 shown in FIG. _4, the differential equation _f 2 (x), that is, when _f 2 (x) is a fifth order polynomial, represented by the following formula (8). Also, DG2 shown in Figure _4, the differential equation _g 2 (y), that is, when _g 2 (y) is a fifth order polynomial, represented by the following formula (9).
DF1: f ₁ ′ (x) = a ₂ + a ₃ x + a ₄ x ² + a ₅ x ³ + a ₆ x ⁴ (6)
_{DG1: g 1 '(y)} = b 2 + b 3 y + b 4 y 2 + b 5 y 3 + b 6 y 4 ... (7)
DF2: f ₂ ′ (x) = c ₂ + c ₃ x + c ₄ x ² + c ₅ x ³ + c ₆ x ⁴ (8)
_{DG2: g 2 '(y)} = d 2 + d 3 y + d 4 y 2 + d 5 y 3 + d 6 y 4 ... (9)

  When obtaining the cylinder center G (xG, yG), the calculation is performed according to the procedures of the flowcharts shown in FIGS. 5 and FIG. 6, D represents the step pitch of the approximate curve C, and L represents the length of the arc corresponding to this step pitch C.

  In the present embodiment, the approximate curve C of the cylindrical member 100 is divided into 360 at a pitch of 1 degree, the arc length L corresponding to 1 degree is expressed by an approximate expression, and then the coordinates of 360 points from this approximate expression are expressed. The cylindrical center G (xG, yG) of the cylindrical member 100 was determined by calculating and arithmetically averaging the X component and Y component of each coordinate.

When the length of the arc corresponding to the angle θ from the reference target A is LT, the arc length LT can be obtained by the following formula (10).
LT = LL / 360 * θ (10)

  When obtaining the position B (xB, yB) for ruled writing, the calculation is performed according to the procedures of the flowcharts shown in FIGS. Specifically, xB can be obtained by the following equation (11).

  yB is obtained by substituting the calculation result of xB into the above equation (1) ′ when the ruled position B is in the same region (first region E1) as the reference target A. It is obtained as follows.

yB = f ₁ (xB) (1) ″

  On the other hand, when the position B (xB, yB) to be marked is in the second area E2, yB can be obtained by the following equation (12).

  xB is obtained by substituting the calculation result of yB into the above equation (2) 'as in the following equation (2)' '.

xB = g ₁ (yB) (2) ″

  On the other hand, when the position B (xB, yB) for marking is in the third region E3, xB can be obtained by the following equation (13).

  yB is obtained by substituting the calculation result of xB into the above equation (3) 'as in the following equation (3)' '.

yB = f ₂ (xB) (3) ″

  On the other hand, when the position B (xB, yB) for ruled writing is in the fourth area E4, yB can be obtained by the following equation (14).

  xB is obtained by substituting the calculation result of yB into the above equation (4) 'as in the following equation (4)' '.

xB = g ₂ (yB) (4) ″

  In addition, when the ruled line S is displayed at the position B (xB, yB) that is separated from the reference target A by the angle θ in the clockwise direction, it can be similarly obtained. In this case, it can be obtained in the order of the first region E1, the fourth region E4, the third region E3, and the second region E2 in the clockwise direction.

  Next, in the display step, the display unit 4 of the laser projector 1 irradiates the laser beam L from the cylindrical center G (xG, yG) toward the position B (xB, yB) where the ruled line is drawn, and the cylindrical member 100. A ruled line S having an appropriate length is displayed on the end face 100a.

  When the ruled line S is displayed on the inner peripheral surface 100b of the cylindrical member 100, as shown in FIG. 9, the distance B from the approximate curve C to the inner peripheral surface 100b is moved from the position B to the cylindrical center G. A point B ′ (xBa, yBa) that has moved in the direction is obtained by calculation. Then, a ruled line S is displayed on the inner peripheral surface 100b from the point B ′ toward the axial direction of the cylindrical member 100.

  Further, when the ruled line S is displayed on the outer peripheral surface 100c of the cylindrical member 100, as shown in FIG. 10, the distance B from the approximate curve C to the outer peripheral surface 100c is opposite to the cylindrical center G from the position B. A point B ″ (xBb, yBb) moved toward the side is obtained by calculation. Then, a ruled line S is displayed on the outer peripheral surface 100 c from the point B ″ toward the axial direction of the cylindrical member 100.

  As described above, according to the present invention, when performing a ruler work with a cylindrical body (cylindrical member) placed horizontally, such as a large tank (container), the body is deformed by its own weight. Even in this case, it is possible to accurately display the position of the ruled line.

  DESCRIPTION OF SYMBOLS 1 ... Laser projector (ruled line display apparatus) 2 ... Measuring part 3 ... Calculation part 4 ... Display part 100 ... Cylindrical member 100a ... End surface 100b ... Inner peripheral surface 100c ... Outer peripheral surface T ... Target A ... Reference target B ... Position where ruled mark C ... Approximate curve G ... Cylinder center LL ... Perimeter length θ ... An angle corresponding to a perfect circle θ '... A corrected angle

Claims (8)

A scribing display device for displaying a scribing position on a cylindrical member,
A measuring unit for measuring the end surface shape of the cylindrical member deformed by its own weight when the cylindrical member is placed horizontally;
Obtaining the circumference and cylindrical center of the cylindrical member from the end face shape of the cylindrical member, converting the angle from the cylindrical center of the cylindrical member into the ratio of the circumferential length, and correcting the angle according to the deformation of the cylindrical member An arithmetic unit for obtaining
A cylindrical member ruler mark display device comprising: a display unit that displays a position of a ruled mark on the cylindrical member with a laser beam based on the corrected angle. The measurement unit arranges a plurality of targets side by side on the end surface of the cylindrical member, measures the positions of the plurality of targets,
The calculation unit obtains an end face shape of the cylindrical member as an approximate curve from position information of the plurality of targets, and obtains a circumferential length and a cylindrical center of the cylindrical member from the approximate curve by calculation. A ruler display device for cylindrical members as described in 1.   The ruler display device for a cylindrical member according to claim 2, wherein the measuring unit includes a three-dimensional measuring instrument for measuring the position of the target.   The said display part irradiates the said laser beam to the end surface of the said cylindrical member, or an inner peripheral surface or an outer peripheral surface, and displays a ruled line in the said ruled position. The ruler display device for the cylindrical member according to the item. A method for displaying a ruled line to display a position of a ruled line on a cylindrical member,
A measuring step for measuring an end face shape of the cylindrical member deformed by its own weight when the cylindrical member is placed horizontally;
Obtaining the circumference and cylindrical center of the cylindrical member from the end face shape of the cylindrical member, converting the angle from the cylindrical center of the cylindrical member into the ratio of the circumferential length, and correcting the angle according to the deformation of the cylindrical member A calculation step for obtaining
And a display step of displaying a position to be marked on the cylindrical member with a laser beam based on the corrected angle. In the measurement step, a plurality of targets are arranged side by side on the end face of the cylindrical member, and the positions of the plurality of targets are measured,
6. In the calculation step, an end face shape of the cylindrical member is obtained as an approximate curve from position information of the plurality of targets, and a circumferential length and a cylinder center of the cylindrical member are obtained by calculation from the approximate curve. A method for displaying a ruled line of a cylindrical member as described in 1.   7. The ruler display method for a cylindrical member according to claim 6, wherein in the measuring step, the position of the target is measured using a three-dimensional measuring instrument.   8. The display step of irradiating an end surface, an inner peripheral surface, or an outer peripheral surface of the cylindrical member with the laser beam, and displaying a ruled line at a position for marking. The method for displaying the ruled sheet of the cylindrical member according to item.

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