JP6362954B2 - Stage mechanism - Google Patents

Description

  The present invention relates to a stage mechanism. Specifically, the present invention relates to a stage mechanism that can move the stage to a desired position and posture.

  Conventionally, a stage mechanism has been used in the field of precision processing, the field of three-dimensional modeling, and the like. The stage mechanism includes a stage to which a processing tool can be attached and a stage that can hold a modeled object. The stage mechanism includes a stage moving unit that moves the stage.

  When processing and shaping, work with high accuracy is required. For this reason, it is necessary to reliably move the stage to an accurate position and posture. The stage is moved using, for example, a stepping motor. In such a case, there is a method of counting the number of steps of the stepping motor from the origin position of the stage as a method of detecting whether the stage is in the correct position and posture. There is also a method of detecting the position and orientation of the stage by attaching an encoder to the movable part of the stage and counting the number of pulses of the encoder.

  However, when detecting the position and orientation of the stage by counting the number of steps of the stepping motor, mechanical errors such as backlash between gears occurring between the stepping motor and the stage may occur, By stepping out, there is a difference between the control position and posture of the stage and the actual position and posture of the stage. For this reason, the exact position and orientation of the stage cannot be detected. In addition, when detecting the position and orientation of the stage by counting the number of pulses of the encoder, it is necessary to connect the encoder and the controller portion with wiring. For this reason, it is necessary to use wiring that can withstand the stress generated when the movable part of the stage moves, or to make a layout that does not interfere with the wiring and the stage, which complicates the structure.

  The present invention has been made in view of this point, and an object of the present invention is to realize a stage mechanism capable of reliably detecting an accurate position and posture of a stage with a simple structure.

  The stage mechanism according to the present invention is provided with a base, a pattern, a stage supported by the base so as to be movable, a stage moving unit that drives the stage, and an image that photographs the pattern provided on the stage. And a detection device that detects the position and orientation of the stage based on the image of the pattern photographed by the photographing device, and when the pattern is viewed from the photographing device, the pattern is: It depends on the position and posture of the stage.

  According to the stage mechanism of the present invention, the detection device detects the position and orientation of the stage based on the pattern image photographed by the photographing device. The pattern that can be seen from the photographing apparatus differs depending on the position and posture of the stage. For this reason, the position and orientation of the stage are uniquely determined by the pattern image photographed by the photographing apparatus. Since the image of the pattern imaged by the imaging device is an image of the pattern provided on the actual stage, the detection device can reliably detect the accurate position and orientation of the stage from the image of the pattern. Thus, according to the present invention, the accurate position and orientation of the stage can be reliably detected with a simple structure without using an encoder for the movable part of the stage. Also, for example, when the stage is moved using a stepping motor, even if a mechanical error such as backlash between gears generated between the stepping motor and the stage occurs or the stepping motor steps out, An accurate position and posture of the stage can be reliably detected.

  According to one aspect of the present invention, a virtual quadrilateral circumscribing the pattern is provided, and the pattern includes a mark.

  According to the above aspect, the position and orientation of the stage are uniquely determined based on the positions of the virtual quadrilateral circumscribing the pattern and the mark in the image photographed by the photographing apparatus.

  According to an aspect of the present invention, the pattern includes rectangular first to fourth sub-patterns each having a long side having the same length and a short side having the same length. The mark is formed on any one of the fourth sub-pattern, and the virtual quadrilateral has the first to fourth vertices as one vertex of each of the first to fourth sub-patterns, The first to fourth sub-patterns are arranged inside the virtual quadrilateral, and the first sub-pattern and the second sub-pattern are the long side of the first sub-pattern and the second sub-pattern. The first sub-pattern and the third sub-pattern are separated from each other in the direction in which the long side of the sub-pattern extends, the short side of the first sub-pattern and the short side of the third sub-pattern Are spaced apart in the extending direction, and the third sub-pattern The fourth sub-pattern is spaced apart in the direction in which the long side of the third sub-pattern and the long side of the fourth sub-pattern extend, and the second sub-pattern and the fourth sub-pattern Are arranged so as to be spaced apart in the direction in which the short side of the second sub-pattern and the short side of the fourth sub-pattern extend.

  According to the above aspect, the position and posture of the stage are uniquely determined based on the shapes of the four sub patterns and the positions of the marks in the image photographed by the photographing apparatus.

  According to an aspect of the present invention, the stage moving unit is configured to drive the stage with six degrees of freedom, and the detection device detects the mark from an image of the pattern photographed by the photographing device. A first calculation unit that calculates a rotation angle around the Z axis of the stage based on the position of the detected mark, and an image of the pattern photographed by the photographing apparatus from the first vertex. A first length from the first vertex to the third vertex; a second length from the first vertex to the third vertex; a second length from the third vertex to the fourth vertex; Calculating a fourth length from the vertex of the second to the fourth vertex, and calculating a rotation angle around the X axis of the stage from a ratio of the first length and the second length, a second calculation unit A third calculator, the third length and the third Based on the fourth calculation unit for calculating the rotation angle around the Y axis of the stage from the ratio to the length, and based on the calculated rotation angle around the X axis, rotation angle around the Y axis, and rotation angle around the Z axis. The position of the stage is detected, and the calculated rotation angle around the X axis, the rotation angle around the Y axis, the rotation angle around the Z axis and the first to fourth lengths, and the origin position are calculated. Based on the first to fourth lengths, a second line connecting the first vertex connecting the first vertex and the fourth vertex, the second vertex, and the third vertex. And a detector for detecting an intersection with the minute as the position of the stage.

  According to the above aspect, the detection device can accurately determine the position and orientation of the stage on the XYZ axes from the position and size of the pattern image including the first to fourth sub patterns in the image captured by the imaging device. Can be reliably detected.

  According to one aspect of the present invention, the stage moving part includes first to sixth guide parts that can be raised and lowered, first to sixth actuators that raise and lower the first to sixth guide parts, respectively, and one end. First to sixth rods having a portion connected to the stage via a first universal joint and the other ends connected to first to sixth guide portions via a second universal joint, respectively. .

  According to the above aspect, the stage moving unit appropriately moves the first to sixth guide units up and down to move the stage in the X axis direction, the Y axis direction, the Z axis direction, the X axis direction, the Y axis direction, and It can be moved around the Z axis. Compared with a stage moving unit that combines a table with an actuator that can move in the X-axis direction, a table with an actuator that can move in the Y-axis direction, and a table with an actuator that can move in the Z-axis direction. be able to. In addition, since a small actuator can be used, the stage moving unit can be miniaturized. Further, since the stage moving unit can drive the stage with six degrees of freedom and freely change the position and posture of the stage, the combination of the position and posture of the stage becomes more complicated. From the position and size of the image, the accurate position and orientation of the stage on the XYZ axes can be reliably detected.

  According to one aspect of the present invention, the imaging device is disposed below the stage.

  In the stage moving unit configured by the 6-degree-of-freedom parallel link mechanism, a space is formed below the stage. For this reason, when the imaging device is arranged below the stage, there is nothing between the imaging device and the stage that prevents the imaging device from imaging the pattern provided on the stage. That is, according to the above aspect, the photographing apparatus can reliably photograph the pattern.

  According to an aspect of the present invention, the detection device is a control position of the stage derived from the position and orientation of the stage detected by the detection unit and the rotation angle of the first to sixth actuators. And a determination unit that determines whether or not the posture and the posture coincide with each other, and the determination unit derives from the position and posture of the stage detected by the detection unit and the rotation angle of the first to sixth actuators. When it is determined that the control position and posture of the stage are different, the control position and posture of the stage derived from the rotation angles of the first to sixth actuators are detected by the detection unit. And a correction unit that corrects the rotation angles of the first to sixth actuators so as to obtain the position and posture of the stage.

  When the actuator is composed of a stepping motor, for example, when the stepping motor steps out, there may be a difference between the control position and posture of the stage and the actual position and posture of the stage. However, according to the above aspect, even when the stepping motor is out of step, the accurate position and orientation of the stage can be detected, and the stepping motor can be corrected out of step by the correction unit.

  According to an aspect of the present invention, the detection device is a control position of the stage derived from the position and orientation of the stage detected by the detection unit and the rotation angle of the first to sixth actuators. And a determination unit that determines whether or not the posture and the posture coincide with each other, and the determination unit derives from the position and posture of the stage detected by the detection unit and the rotation angle of the first to sixth actuators. And a stop unit that stops the operation of the first to sixth actuators when it is determined that the control position and posture of the stage are different.

  When the actuator is composed of a stepping motor, for example, when the stepping motor steps out, there may be a difference between the control position and posture of the stage and the actual position and posture of the stage. However, according to the above aspect, the accurate position and orientation of the stage can be detected even when the stepping motor is out of step, and the operation of the stepping motor is stopped by the stop unit to stop driving the stage. be able to.

  According to an aspect of the present invention, the imaging device is configured by two or more cameras, and each of the cameras captures the pattern from different positions.

  According to the above aspect, even when the pattern provided on the stage cannot be photographed with one camera when the stage is largely inclined, the camera is arranged so that the pattern can be photographed with the other camera. Can do. That is, even when the movable area of the stage is further expanded, the accurate position and posture of the stage can be reliably detected.

  According to an aspect of the present invention, when the pattern is captured by at least two or more of the cameras, the detection apparatus captures the largest pattern among the captured images of the pattern. Based on the obtained image, the position and posture of the stage are detected.

  According to the above aspect, since the detection device detects the position and posture of the stage based on the image captured with the largest pattern, the accurate position and posture of the stage can be detected more reliably.

  The three-dimensional modeling apparatus according to the present invention is a three-dimensional modeling apparatus that three-dimensionally models a modeled object by sequentially curing a resin material and sequentially laminating resins having a predetermined cross-sectional shape, the stage mechanism and the base A modeling head including a nozzle for discharging a resin material, the resin material discharged from the nozzle is held on the upper surface of the stage, and the pattern is formed on the lower surface of the stage. The imaging device is provided below the stage.

  If the resin material discharged from the nozzles covers the pattern and the pattern becomes dirty, the detection device cannot detect the position and orientation of the stage based on the captured pattern image. However, according to the three-dimensional modeling apparatus according to the present invention, the resin material discharged from the nozzle is held on the upper surface of the stage, and the resin material is not discharged onto the lower surface of the stage provided with the pattern. For this reason, the pattern is not covered with the resin material. As a result, the detection apparatus can reliably detect the accurate position and posture of the stage from the captured pattern image.

  ADVANTAGE OF THE INVENTION According to this invention, the stage mechanism which can detect the exact position and attitude | position of a stage reliably is realizable with a simple structure.

It is a perspective view which shows the structure of the three-dimensional modeling apparatus provided with the stage mechanism which concerns on one Embodiment. It is a side view which shows the structure of the three-dimensional modeling apparatus provided with the stage mechanism which concerns on one Embodiment. It is a top view which shows the structure of the three-dimensional modeling apparatus which concerns on one Embodiment. It is a bottom view which shows the stage in which the pattern which concerns on one Embodiment was provided. It is a bottom view which shows the stage in which the pattern which concerns on one Embodiment was provided. It is a block diagram of the main elements of the stage mechanism concerning one embodiment. It is a schematic diagram showing a state when the stage which concerns on one Embodiment rotates around the Z-axis. It is a schematic diagram showing a state when the stage which concerns on one Embodiment rotates around the X-axis. It is a schematic diagram showing a state when the stage which concerns on one Embodiment rotates around the Y-axis. 5 is a flowchart of stage position and orientation detection processing and correction processing in a stage mechanism according to an embodiment. It is a side view which shows the structure of the three-dimensional modeling apparatus provided with the stage mechanism which concerns on other one Embodiment. It is a top view which shows the structure of the stage mechanism which concerns on other one Embodiment. It is a block diagram of the main elements of the stage mechanism concerning other one embodiment. It is a flowchart of the detection process and stop process of the position and attitude | position of a stage in the stage mechanism which concerns on other one Embodiment. It is a bottom view which shows the stage provided with the pattern which concerns on other one Embodiment. It is a bottom view which shows the stage provided with the pattern which concerns on other one Embodiment.

<First Embodiment>
Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the three-dimensional modeling apparatus 10 according to this embodiment includes a stage mechanism 30. The three-dimensional modeling apparatus 10 three-dimensionally models a modeled object by curing a resin material and sequentially laminating resins having a predetermined cross-sectional shape. Examples of the resin material include a thermoplastic resin, a photocurable resin, and an ultraviolet curable resin. In the following description, a case where the stage mechanism 30 is used in the three-dimensional modeling apparatus 10 will be described as an example. However, the application target of the present invention is not intended to be limited to such a type of apparatus.

In the following description, unless otherwise specified, the left, right, top, and bottom in FIG. 2 are the left, right, top, and bottom of the three-dimensional modeling apparatus 10, respectively. The left, right, top, and bottom in FIG. 3 are the front, back, left, and right of the three-dimensional modeling apparatus 10, respectively. Reference numerals F, Rr, L, R, Up, and Dn in the drawings represent front, rear, left, right, upper, and lower, respectively. The symbol X in the drawing indicates the X axis and represents the left-right direction. The symbol Y in the drawing indicates the Y axis and indicates the front-rear direction. The symbol Z in the drawing indicates the Z axis and indicates the vertical direction. The symbols θ _X , θ _Y , and θ _Z represent the rotation directions around the X axis, the Y axis, and the Z axis, respectively. In the present embodiment, the X axis, the Y axis, and the Z axis are set so that any one axis is orthogonal to the other two axes. However, the X axis, the Y axis, and the Z axis may be set so that any one of the axes intersects the other two axes. Moreover, these are only directions for convenience of description, and do not limit the installation mode of the three-dimensional modeling apparatus 10 at all.

  As shown in FIG. 1, the three-dimensional modeling apparatus 10 includes a stage mechanism 30, a holder 15, and a modeling head 20.

  As shown in FIG. 1, the stage mechanism 30 includes a base 40, a stage 50, a stage moving unit 60, a camera 70 as an imaging device, and a computer 75 as a detection device.

  As shown in FIG. 2, the base 40 includes a first base 42, six struts 44, and a second base 46. The first base 42 is formed in a disc shape. The support column 44 extends upward from the first base 42. The second base 46 is formed in a disc shape. As shown in FIG. 3, an opening 47 is formed in the second base 46. As shown in FIG. 2, the second base 46 is disposed above the first base 42. The second base 46 is disposed on the six struts 44. The diameter of the first base 42 and the diameter of the second base 46 are substantially the same.

  As shown in FIG. 1, the stage 50 is formed in a disk shape. The stage 50 is movably supported by the base 40. The stage 50 is disposed below the modeling head 20. The stage 50 is disposed above the first base 42 and below the second base 46. The stage 50 may be disposed above the second base 46 as long as the stage 50 is disposed below the modeling head 20. The stage 50 holds the resin material discharged from the nozzle 22 of the modeling head 20 described later. Specifically, the resin material is held on the upper surface 50U of the stage 50. The modeled object is modeled on the upper surface 50U of the stage 50. The stage 50 is provided with a pattern 80 (see FIG. 4) described later. Specifically, a pattern 80 is provided on the lower surface 50 </ b> B (see FIG. 2) of the stage 50. The shape of the stage 50 is stored in the computer 75 in advance.

  As shown in FIG. 1, the stage moving unit 60 is disposed on the base 40. The stage moving unit 60 drives the stage 50 with six degrees of freedom. The stage moving unit 60 drives the stage 50 with three degrees of freedom of translation and three degrees of freedom of rotation. That is, the stage moving unit 60 is configured to translate the stage 50 in the X-axis direction, the Y-axis direction, and the Z-axis direction, and to rotate and move the X-axis, Y-axis, and Z-axis. Yes.

  As shown in FIG. 2, the stage moving unit 60 is configured by a 6-degree-of-freedom parallel link mechanism. The stage moving unit 60 includes six rods 62 connected to the stage 50, and six guide units 64 that are connected to the rods 62 and can be moved up and down along the column 44 (only two are shown in FIG. 2). ) And six actuators 65 (only two are shown in FIG. 2) for moving the guide portion 64 up and down. The rod 62, the guide part 64, and the actuator 65 are disposed on the base 40. The rod 62 includes a first universal joint 63A at one end 62A thereof. The rod 62 includes a second universal joint 63B at the other end 62B. The first universal joint 63A supports the stage 50. The first universal joint 63A connects one end 62A of the rod 62 and the stage 50.

  The guide portion 64 is configured by a slider that is slidably engaged with the support column 44. As shown in FIG. 2, the second universal joint 63 </ b> B is connected to the guide portion 64. The second universal joint 63 </ b> B connects the other end 62 </ b> B of the rod 62 and the guide portion 64. A groove is formed in the support 44, and a ball screw 66 extending vertically is disposed inside the groove. An actuator 65 that rotates the ball screw 66 is disposed at the upper end of the ball screw 66. Although the kind of actuator 65 is not limited at all, for example, a servo motor can be used. The guide portion 64 is formed with a screw hole (not shown) extending vertically. A ball screw 66 is inserted into the screw hole of the guide portion 64, and the screw hole of the guide portion 64 meshes with the ball screw 66. Therefore, when the ball screw 66 rotates, the guide portion 64 rises, and when the ball screw 66 rotates reversely, the guide portion 64 descends. The rod 62 moves as the guide portion 64 moves up and down.

  Each actuator 65 can operate independently, and each actuator 65 moves each rod 62 independently of each other. The actuator 65 is electrically connected to a circuit board 68 disposed above the base 40. The circuit board 68 is disposed on the second base 46. As the six rods 62 move independently of each other, the stage 50 moves in the base 40 in the X-axis direction, the Y-axis direction, the Z-axis direction, and the X-axis direction. A rotational movement, a rotational movement around the Y axis, and a rotational movement around the Z axis are possible. By moving the six rods 62 independently of each other, the position and posture of the stage 50 can be freely set.

  As shown in FIG. 1, the camera 70 photographs a pattern 80 (see FIG. 4) provided on the stage 50. The camera 70 is disposed at a position where a pattern can be photographed. The camera 70 is disposed on the base 40. The camera 70 is disposed below the stage 50. The camera 70 is disposed on the first base 42. The camera 70 is disposed at the center of the first base 42. The center 72 </ b> C of the lens 72 of the camera 70 is disposed at the center of the first base 42. The camera 70 may be disposed to be inclined with respect to the first base 42. An image of the pattern 80 photographed by the camera 70 is output to the computer 75.

  As shown in FIG. 4, the pattern 80 is provided on the stage 50. The pattern 80 is provided on the lower surface 50 </ b> B of the stage 50. The pattern 80 includes a first sub pattern 81, a second sub pattern 82, a third sub pattern 83, and a fourth sub pattern 84. The first to fourth sub patterns 81 to 84 are formed in a rectangular shape. Each of the first to fourth sub-patterns 81 to 84 includes a long side 85L having the same length and a short side 85S having the same length. In the present embodiment, the length of the long side 85L is L, and the length of the short side 85S is S.

  As shown in FIG. 4, a mark 86 is formed on the second sub-pattern 82. The mark 86 is formed in a rectangular shape, but the shape and size of the mark 86 are not particularly limited. In the present embodiment, the mark 86 is formed on the second sub-pattern 82, but it is formed on any of the first sub-pattern 81, the third sub-pattern 83, or the fourth sub-pattern 84. May be. The mark 86 differs depending on the position and posture of the stage 50 when the mark 86 is viewed from the camera 70. That is, the shape and position of the mark 86 when the mark 86 is viewed from the camera 70 differ depending on the position and posture of the stage 50. The mark 86 is an indication for the computer 75 to recognize the pattern 80 in the image of the pattern 80 photographed by the camera 70. In the present embodiment, this is an indication for the computer 75 to identify and recognize the first subpattern 81, the second subpattern 82, the third subpattern 83, and the fourth subpattern 84 included in the pattern 80. .

  As shown in FIG. 5, the pattern 80 includes a vertex 81T of the first subpattern 81, a vertex 82T of the second subpattern 82, a vertex 83T of the third subpattern 83, and a vertex of the fourth subpattern 84. A virtual quadrangle 88 having a vertex 84T is provided. The virtual quadrangle 88 circumscribes the pattern 80. Inside the virtual quadrangle 88, first to fourth sub patterns 81 to 84 are arranged. The virtual quadrangle 88 circumscribes the first to fourth sub patterns 81 to 84. The vertex 81T is a vertex farthest from the fourth sub pattern 84 among the vertices of the first sub pattern 81. The vertex 82T is a vertex farthest from the third sub pattern 83 among the vertices of the second sub pattern 82. The vertex 83T is a vertex farthest from the second sub pattern 82 among the vertices of the third sub pattern 83. The vertex 84 </ b> T is a vertex farthest from the first sub pattern 81 among the vertices of the fourth sub pattern 84. The pattern 80 differs depending on the position and posture of the stage 50 when the pattern 80 is viewed from the camera 70. That is, the shape of the pattern 80 when the pattern 80 is viewed from the camera 70 varies depending on the position and posture of the stage 50.

  As shown in FIG. 4, the first sub-pattern 81 and the second sub-pattern 82 are separated from each other in the direction in which the long side 85L of the first sub-pattern 81 and the long side 85L of the second sub-pattern 82 extend. Has been placed. The first sub pattern 81 and the second sub pattern 82 are spaced apart by the length L of the long side 85L. The long side 85L of the first sub pattern 81 and the long side 85L of the second sub pattern 82 are arranged in parallel. The first sub pattern 81 and the third sub pattern 83 are spaced apart from each other in the direction in which the short side 85S of the first sub pattern 81 and the short side 85S of the third sub pattern 83 extend. The first sub pattern 81 and the third sub pattern 83 are spaced apart by the length S of the short side 85S. The short side 85S of the first sub pattern 81 and the short side 85S of the third sub pattern 83 are arranged in parallel. The third sub pattern 83 and the fourth sub pattern 84 are spaced apart in the direction in which the long side 85L of the third sub pattern 83 and the long side 85L of the fourth sub pattern 84 extend. The third sub pattern 83 and the fourth sub pattern 84 are spaced apart by the length L of the long side 85L. The long side 85L of the third sub pattern 83 and the long side 85L of the fourth sub pattern 84 are arranged in parallel. The second sub pattern 82 and the fourth sub pattern 84 are spaced apart from each other in the direction in which the short side 85S of the second sub pattern 82 and the short side 85S of the fourth sub pattern 84 extend. The second sub pattern 82 and the fourth sub pattern 84 are spaced apart by the length S of the short side 85S. The short side 85S of the second sub pattern 82 and the short side 85S of the fourth sub pattern 84 are arranged in parallel.

  As shown in FIG. 5, a line segment connecting the first vertex 81T of the first sub-pattern 81 and the fourth vertex 84T of the fourth sub-pattern 84 is defined as the first line segment 89A, and the second sub-pattern When a line segment connecting the second vertex 82T of the pattern 82 and the third vertex 83T of the third sub-pattern 83 is a second line segment 89B, the first line segment 89A and the second line segment 89B 89C is a reference point indicating the position and orientation of the stage 50. The intersection 89C is provided at the center of the lower surface 50B of the stage 50.

  As shown in FIG. 4, the first sub-pattern 81 and the second sub-pattern 82 are spaced apart by the length L of the long side 85L, and the third sub-pattern 83 and the fourth sub-pattern 84 are arranged. Is spaced apart by the length L of the long side 85L, but is not limited to this. As long as the distance between the first sub-pattern 81 and the second sub-pattern 82 and the distance between the third sub-pattern 83 and the fourth sub-pattern 84 are the same, the length L of the long side 85L May be of different lengths. The first sub pattern 81 and the third sub pattern 83 are spaced apart by the length S of the short side 85S, and the second sub pattern 82 and the fourth sub pattern 84 are of the short side 85S. Although it is spaced apart by the length S, it is not limited to this. As long as the distance between the first sub-pattern 81 and the third sub-pattern 83 and the distance between the second sub-pattern 82 and the fourth sub-pattern 84 are the same, the length S of the short side 85S May be of different lengths.

  As shown in FIG. 1, the holder 15 is disposed above the base 40. The holder 15 is disposed on the second base 46. The holder 15 is disposed so as to straddle the opening 47 of the second base 46. The holder 15 includes a first wall 13 and a second wall 14 that support the modeling head 20. A modeling head 20 is disposed between the first wall 13 and the second wall 14.

  As shown in FIG. 1, the modeling head 20 is disposed above the base 40. The modeling head 20 is fixed to the holder 15. The modeling head 20 includes a nozzle 22 that discharges a resin material. As shown in FIG. 3, the nozzle 22 overlaps the opening 47 of the second base 46 in plan view.

  As shown in FIG. 1, the three-dimensional modeling apparatus 10 includes a tank 24 that stores a resin material, and a resin supply path 26. The tank 24 is disposed above the base 40. The tank 24 is disposed in the holder 15. The tank 24 is replaceable. The resin supply path 26 is connected to the tank 24 and the modeling head 20. The resin material in the tank 24 is supplied to the modeling head 20 via the resin supply path 26. Examples of the resin supply path 26 include a flexible tube. The resin supply path 26 may be a metal pipe. A motor 28 is disposed in the holder 15. By driving the motor 28, the resin material in the resin supply path 26 can be supplied to the modeling head 20. The motor 28 is electrically connected to a circuit board 68 described later. The motor 28 is controlled by a computer 75.

  The computer 75 detects the position and orientation of the stage 50 based on the image of the pattern 80 photographed by the camera 70. The computer 75 is communicably connected to the stage mechanism 30. The stage mechanism 30 may be always connected to the computer 75 or may be connected appropriately. Further, the connection between the stage mechanism 30 and the computer 75 is not limited to a wired connection, and may be a wireless connection. The computer 75 may include a central processing unit (hereinafter referred to as a CPU), a ROM storing a program executed by the CPU, a RAM, and the like. The computer 75 may be a dedicated computer for the stage mechanism 30 or a general-purpose computer such as a personal computer.

  As shown in FIG. 6, the computer 75 includes a first calculation unit 91, a second calculation unit 92, a third calculation unit 93, a fourth calculation unit 94, a detection unit 95, a determination unit 96, and a correction. Part 97.

  The first calculator 91 detects the mark 86 from the image of the pattern 80 photographed by the camera 70. The first calculation unit 91 calculates the rotation angle α (see FIG. 7) around the Z axis of the stage 50 based on the detected position of the mark 86. In FIG. 7, a two-dot chain line represents a state in which the pattern 80 exists at the origin position. A solid line represents a state when the pattern 80 is rotated by an angle α around the Z axis with respect to the origin position.

  The origin position of this embodiment is determined based on the following (1) to (5). (1) The first base 42 and the stage 50 are arranged in parallel. (2) The center 72C of the lens 72 of the camera 70 is arranged at the center of the first base 42. (3) An intersection 89C of the pattern 80 is provided at the center of the lower surface 50B of the stage 50. (4) An intersection 89C of the pattern 80 is arranged on a perpendicular line U (see FIG. 2) passing through the center 72C of the lens 72. (5) The mark 86 is arranged at a predetermined position. In this embodiment, the stage 50 and the first base 42 are arranged in parallel, the stage 50 is not rotated about the X axis, the Y axis, and the Z axis, and the pattern 80 is viewed from the camera 70. The position of the stage 50 when the long side 85L of the first to fourth sub-patterns 81 to 84 extends parallel to the X axis and the short side 85S extends parallel to the Y axis. The origin position can be arbitrarily determined. As information about the origin position, length information of first to fourth lengths L1 to L4 described later in the image of the pattern 80 photographed by the camera 70 with the pattern 80 being at the origin position is rotation of the stage 50. Required for angle detection and position detection. The lengths of the first to fourth lengths L1 to L4 in the image of the pattern 80 photographed by the camera 70 in a state where the pattern 80 is at the origin position are calculated in advance. Information about these origin positions is stored in the computer 75 in advance. The relationship between the position of the mark 86 and the rotation angle α is stored in the computer 75 in advance.

  As shown in FIG. 5, the second calculation unit 92 includes an apex 81T of the first subpattern 81, an apex 82T of the second subpattern 82, and a third in the image of the pattern 80 captured by the camera 70. The vertex 83T of the sub-pattern 83 and the vertex 84T of the fourth sub-pattern 84 are detected. The second calculation unit 92 includes a first length L1 from the first vertex 81T to the second vertex 82T, and a third vertex 83T to a fourth vertex 84T in the image of the pattern 80 photographed by the camera 70. A second length L2 from the first vertex 81T to the third vertex 83T, and a fourth length L4 from the second vertex 82T to the fourth vertex 84T. calculate. The second calculator 92 may calculate the first to fourth lengths L1 to L4 with subpixel accuracy. The first to fourth lengths L1 to L4 vary depending on the position and posture of the stage 50. The 2nd calculation part 92 calculates the length of the 1st-4th length L1-L4 in the image of the pattern 80 image | photographed with the camera 70 in the state in which the pattern 80 exists in an origin position.

  The third calculator 93 calculates the rotation angle γ around the X axis of the stage 50 (see FIG. 8) from the ratio between the first length L1 and the second length L2 calculated by the second calculator 92. In FIG. 8, a two-dot chain line represents a state where the pattern 80 exists at the origin position. A solid line represents a state when the pattern 80 is rotated by an angle γ about the X axis with respect to the origin position. The relationship between the ratio between the first length L1 and the second length L2 and the rotation angle γ is stored in the computer 75 in advance.

  The fourth calculator 94 calculates the rotation angle β around the Y axis of the stage 50 (see FIG. 9) from the ratio between the third length L3 and the fourth length L4 calculated by the second calculator 92. In FIG. 9, a two-dot chain line represents a state in which the pattern 80 exists at the origin position. A solid line represents a state when the pattern 80 is rotated by an angle β around the Y axis with respect to the origin position. The relationship between the ratio between the third length L3 and the fourth length L4 and the rotation angle β is stored in the computer 75 in advance.

  The detection unit 95 detects the posture of the stage 50. The detection unit 95 includes a rotation angle γ around the X axis calculated by the third calculation unit 93, a rotation angle β around the Y axis calculated by the fourth calculation unit 94, and a Z calculated by the first calculation unit 91. The posture of the stage 50 is detected based on the rotation angle α around the axis. The detection unit 95 detects the position of the stage 50. The detection unit 95 includes a rotation angle γ around the X axis calculated by the third calculation unit 93, a rotation angle β around the Y axis calculated by the fourth calculation unit 94, and a Z calculated by the first calculation unit 91. Based on the rotation angle α around the axis, the first to fourth lengths L1 to L4 calculated by the second calculation unit 92, and the first to fourth lengths L1 to L4 calculated at the origin position, the first A first line segment 89A (see FIG. 5) connecting the first vertex 81T and the fourth vertex 84T (see FIG. 5), and a second line segment 89B (see FIG. 5) connecting the second vertex 82T and the third vertex 83T. Is detected as the position of the stage 50. As shown in FIG. 8, the distance M between the intersection 89C of the pattern 80 (see FIG. 5) provided on the stage 50 and the center 72C of the lens 72 of the camera 70 and the XYZ coordinates of the intersection 89C, that is, the position of the stage 50 are 50 postures, that is, the rotation angle α, the rotation angle β, and the rotation angle γ, the first to fourth lengths L1 to L4 calculated by the second calculator 92, and the first to fourth calculated at the origin position. It is calculated based on the lengths L1 to L4. Since the shape of the stage 50 is stored in the computer 75 in advance, any position of the upper surface 50U and the lower surface 50B of the stage 50 can be detected by detecting the intersection 89C. Information regarding the position and orientation of the stage 50 detected by the detection unit 95 is output to the determination unit 96.

  The determination unit 96 controls the position and posture of the stage 50 detected from the position and posture of the stage 50 (hereinafter also referred to as “actual position”) detected by the detection unit 95 and the rotation angle of each actuator 65. (Hereinafter, also referred to as “control position”) is determined. Information regarding the rotation angle of each actuator 65 is constantly output to the determination unit 96. If the determination unit 96 determines that the actual position and the control position are different, the determination unit 96 outputs a signal to the correction unit 97. Note that the control position and orientation of the stage 50 may be derived from the number of steps of the actuator 65.

  The correction unit 97 receives the signal from the determination unit 96, that is, the position and posture of the stage 50 detected by the detection unit 95, and the control position and posture of the stage 50 derived from the rotation angle of each actuator 65. , The rotation angle of each actuator 65 is corrected so that the control position and posture of the stage 50 derived from the rotation angle of each actuator 65 become the position and posture of the stage 50 detected by the detection unit 95. To do.

  Next, detection and correction of the position and orientation of the stage 50 in the stage mechanism 30 according to the present embodiment will be described with reference to FIG. FIG. 10 is a flowchart of the process for detecting and correcting the position and orientation of the stage 50 in the stage mechanism 30 according to the present embodiment.

  First, when the three-dimensional modeling apparatus 10 starts three-dimensional modeling of a modeled object, the stage 50 moves to sequentially stack the resin materials discharged from the nozzles 22 and form a resin layer having a predetermined cross-sectional shape. Thereby, in the stage mechanism 30, the detection process and correction process of the position and orientation of the stage 50 are started.

  In step S <b> 10, the camera 70 captures the pattern 80 provided on the stage 50. The captured image of the pattern 80 is output to the computer 75.

  Next, in step S20, the second calculation unit 92 detects the positions and orientations of the sub patterns 81 to 84. Specifically, the second calculation unit 92 extracts a black region from the image of the pattern 80 photographed in step S10. For example, in the image of the pattern 80, an area where the pixel luminance is lower than a preset threshold is extracted as a black area. The second calculator 92 detects the position and size of each extracted black region with subpixel accuracy. The second calculation unit 92 is substantially configured such that the length of the long side of one black region, the length of the long side of the other black region, and the distance between the one black region and the other black region are substantially equal. Detect the same length. In the example shown in FIG. 4, a pair of the first sub pattern 81 and the second sub pattern 82 and a pair of the third sub pattern 83 and the fourth sub pattern 84 are detected. The second calculation unit 92 is configured such that the length of the short side of one black region, the length of the short side of the other black region, and the distance between the one black region and the other black region are substantially equal. Detect the same length. In the example shown in FIG. 4, a pair of the first sub pattern 81 and the third sub pattern 83 and a pair of the second sub pattern 82 and the fourth sub pattern 84 are detected. In this way, the second calculation unit 92 detects the pattern 80, that is, the first to fourth sub patterns 81 to 84.

  Next, in step S <b> 30, the first calculation unit 91 detects the mark 86 from the image of the pattern 80 captured by the camera 70. Specifically, the first calculation unit 91 detects and detects the subpattern in which the mark 86 is formed from the first to fourth subpatterns 81 to 84 detected by the second calculation unit 92. Based on the position of the mark 86, the rotation angle α around the Z axis of the stage 50 (see FIG. 7) is calculated.

  Next, in step S40, the second calculation unit 92 detects the vertices 81T to 84T of the first to fourth sub patterns 81 to 84 in the image of the pattern 80 photographed by the camera 70. The first to fourth sub-patterns 81 to 84 are arranged inside the virtual quadrangle 88 having the vertices 81T to 84T as vertices. The virtual quadrangle 88 circumscribes the first to fourth sub patterns 81 to 84.

  Next, in step S50, the second calculation unit 92 calculates the first length L1 from the first vertex 81T to the second vertex 82T and the third vertex based on the detected vertices 81T to 84T. The second length L2 from 83T to the fourth vertex 84T, the third length L3 from the first vertex 81T to the third vertex 83T, and the second length L3 from the second vertex 82T to the fourth vertex 84T 4 lengths L4 are calculated.

  Next, in step S60, the third calculation unit 93 determines the rotation angle γ around the X axis of the stage 50 from the ratio of the first length L1 and the second length L2 calculated by the second calculation unit 92 (see FIG. 8).

  Next, in step S70, the fourth calculation unit 94 determines the rotation angle β around the Y axis of the stage 50 from the ratio of the third length L3 and the fourth length L4 calculated by the second calculation unit 92 (see FIG. 9) is calculated.

  Next, in step S <b> 80, the detection unit 95 detects the posture and position of the stage 50. The detection unit 95 includes a rotation angle γ around the X axis calculated by the third calculation unit 93, a rotation angle β around the Y axis calculated by the fourth calculation unit 94, and a Z calculated by the first calculation unit 91. The posture of the stage 50 is detected based on the rotation angle α around the axis. The detection unit 95 includes the rotation angle γ, the rotation angle β, the rotation angle α, the first to fourth lengths L1 to L4 calculated by the second calculation unit 92, and the first to fourth calculated at the origin position. Based on the lengths L1 to L4, the first line segment 89A (see FIG. 5) connecting the first vertex 81T and the fourth vertex 84T (see FIG. 5), the second vertex 82T, and the third vertex 83T are connected. The intersection 89C with the second line segment 89B (see FIG. 5) is detected as the position of the stage 50. As shown in FIG. 8, the distance M between the intersection 89C of the pattern 80 (see FIG. 5) provided on the stage 50 and the center 72C of the lens 72 of the camera 70 and the XYZ coordinates of the intersection 89C, that is, the position of the stage 50 are 50 postures, that is, the rotation angle α, the rotation angle β, and the rotation angle γ, the first to fourth lengths L1 to L4 calculated by the second calculator 92, and the first to fourth calculated at the origin position. It is calculated based on the lengths L1 to L4.

  Next, in step S <b> 90, the determination unit 96 determines the control position and position of the stage 50 derived from the position and orientation of the stage 50 (that is, the actual position) detected by the detection unit 95 and the rotation angle of each actuator 65. It is determined whether or not the posture (that is, the control position) matches. If it is determined in step S90 that the actual position matches the control position, the computer 75 ends the position and orientation detection processing and correction processing of the stage 50. On the other hand, if the determination unit 96 determines that the actual position does not match the control position, the process proceeds to step S100. At this time, the determination unit 96 outputs a signal to the correction unit 97.

  In step S100, the correction unit 97 corrects the rotation angle of each actuator 65 so that the control position becomes the actual position. When the correction unit 97 corrects the rotation angle of each actuator 65 and the control position coincides with the actual position, the computer 75 ends the detection processing and correction processing of the position and orientation of the stage 50. Such detection and correction processing of the position and orientation of the stage 50 may be performed every time the stage 50 moves, or may be performed at regular intervals.

  As described above, according to the stage mechanism 30, the computer 75 detects the position and orientation of the stage 50 based on the image of the pattern 80 captured by the camera 70. The pattern 80 visible from the camera 70 varies depending on the position and posture of the stage 50. For this reason, the position and orientation of the stage 50 are uniquely determined by the image of the pattern 80 photographed by the camera 70. Since the image of the pattern 80 photographed by the camera 70 is an image of the pattern 80 provided on the actual stage 50, the computer 75 reliably detects the accurate position and orientation of the stage 50 from the image of the pattern 80. can do. As described above, according to the stage mechanism 30, it is possible to reliably detect the accurate position and posture of the stage 50 with a simple structure without using an encoder for the movable part of the stage 50. Also, for example, when the stage 50 is moved using a stepping motor, mechanical errors such as backlash between the gears generated between the stepping motor and the stage 50 may occur, or the stepping motor may step out. In addition, the accurate position and posture of the stage 50 can be reliably detected.

  According to the stage mechanism 30 of the present embodiment, as shown in FIG. 5, the stage mechanism 30 includes a virtual quadrilateral 88 circumscribing the pattern 80, and the pattern 80 includes a mark 86. Thus, the position and orientation of the stage 50 are uniquely determined based on the positions of the virtual quadrilateral 88 and the mark 86 circumscribing the pattern 80 in the image taken by the camera 70.

  According to the stage mechanism 30 of the present embodiment, the computer 75 includes a detection unit 95 as shown in FIG. Based on the calculated rotation angle γ around the X axis (see FIG. 8), rotation angle β around the Y axis (see FIG. 9), and rotation angle α around the Z axis (see FIG. 7), The posture of the stage 50 is detected. The detection unit 95 includes a rotation angle γ around the X axis, a rotation angle β around the Y axis, a rotation angle α around the Z axis, the first to fourth lengths L1 to L4 calculated by the second calculation unit 92, and Based on the first to fourth lengths L1 to L4 calculated at the origin position, an intersection 89C between the first line segment 89A and the second line segment 89B is detected as the position of the stage 50. Accordingly, the computer 75 can reliably detect the accurate position and posture of the stage 50 from the image of the pattern 80 including the first to fourth sub patterns 81 to 84.

  According to the stage mechanism 30 of the present embodiment, as shown in FIG. 1, the stage moving unit 60 appropriately moves the guide units 64 up and down to move the stage 50 in the X axis direction, the Y axis direction, and the Z axis direction. , Around the X axis, around the Y axis, and around the Z axis. Compared to a stage moving unit that combines a table with an actuator that can move in the X-axis direction, a table with an actuator that can move in the Y-axis direction, and a table with an actuator that can move in the Z-axis direction, the output of the actuator 65 Can be suppressed. Moreover, since a small actuator can be used, the stage moving part 60 can be reduced in size. The stage moving unit 60 can drive the stage 50 with six degrees of freedom and freely change the position and posture of the stage 50. For this reason, variations in the position and orientation of the stage 50 are more complicated, but the computer 75 reliably detects the accurate position and orientation of the stage 50 on the XYZ axes from the position and size of the image of the pattern 80. be able to.

  According to the stage mechanism 30 of the present embodiment, as shown in FIG. 2, the camera 70 is disposed below the stage 50 and on the first base 42. In the stage moving unit 60 configured by a 6-degree-of-freedom parallel link mechanism, a space is formed between the stage 50 and the first base 42. For this reason, when the camera 70 is arranged below the stage 50 and on the first base 42, there is something between the camera 70 and the stage 50 that prevents the camera 70 from photographing the pattern 80 provided on the stage 50. not exist. As a result, the camera 70 can reliably capture the pattern 80.

  According to the stage mechanism 30 of the present embodiment, the computer 75 includes a correction unit 97 as shown in FIG. When the actuator 65 is composed of a stepping motor, for example, when the stepping motor steps out, there may be a difference between the control position and posture of the stage 50 and the actual position and posture of the stage 50. However, according to the above aspect, even when the stepping motor is out of step, the accurate position and orientation of the stage 50 can be detected, and the correction unit 97 can correct the stepping motor out of step.

  According to the three-dimensional modeling apparatus 10 of the present embodiment, as shown in FIG. 1, the resin material discharged from the nozzle 22 is held by the upper surface 50U of the stage 50, and the pattern 80 is provided on the lower surface 50B of the stage 50. The camera 70 is disposed below the stage 50. If the pattern 80 becomes dirty due to the resin material discharged from the nozzles 22 covering the pattern 80, the computer 75 cannot detect the position and orientation of the stage 50 based on the captured image of the pattern 80. However, according to the three-dimensional modeling apparatus 10, the resin material discharged from the nozzle 22 is held on the upper surface 50U of the stage 50, and no resin material is discharged onto the lower surface 50B of the stage 50 on which the pattern 80 is provided. For this reason, the pattern 80 is not covered with the resin material. As a result, the computer 75 can reliably detect the accurate position and orientation of the stage 50 from the captured image of the pattern 80.

Second Embodiment
FIG. 11 is a side view illustrating the structure of the three-dimensional modeling apparatus 10 including the stage mechanism 30 according to the second embodiment. FIG. 12 is a plan view of the stage mechanism 30 according to the second embodiment. In FIG. 12, the rod 62 and the second base 46 are not shown for convenience of explanation.

  As shown in FIG. 11, the stage mechanism 30 includes three cameras 70 arranged at different positions. As shown in FIG. 12, the cameras 70 are arranged at equal intervals in the circumferential direction of the first base 42. The interval between the cameras 70 is not limited to an equal interval and is arbitrary. Each camera 70 images the pattern 80 provided on the stage 50 from a different position. The number of cameras 70 is not limited to three, and may be two or four or more.

  The computer 75 detects the position and orientation of the stage 50 based on an image in which the pattern 80 is captured most greatly among images of the pattern 80 captured by each camera 70.

  The first calculation unit 91 detects the mark 86 from the image in which the pattern 80 is photographed the largest among the images of the pattern 80 photographed by each camera 70. The first calculation unit 91 calculates the rotation angle α (see FIG. 7) around the Z axis of the stage 50 based on the detected position of the mark 86.

  The second calculation unit 92 includes a vertex 81T (see FIG. 5), a vertex 82T (see FIG. 5), a vertex in the image in which the pattern 80 is photographed the largest among the images of the pattern 80 photographed by each camera 70. 83T (see FIG. 5) and vertex 84T (see FIG. 5) are detected. The second calculation unit 92 calculates the first to fourth lengths L1 to L4 (see FIG. 5) in the image in which the pattern 80 is photographed most greatly among the images of the pattern 80 photographed by each camera 70.

  According to the stage mechanism 30 according to the present embodiment, as shown in FIG. 11, the camera 70 includes two or more cameras, and each camera 70 captures the pattern 80 from a mutually different position. Even when one camera 70 cannot capture the pattern 80 provided on the stage 50 when the stage 50 is greatly inclined, the camera 70 is arranged so that the other camera 70 can capture the pattern 80. be able to. That is, even when the movable region of the stage 50 is further expanded, the accurate position and posture of the stage 50 can be reliably detected.

  According to the stage mechanism 30 according to the present embodiment, the computer 75 detects the position and orientation of the stage 50 based on the image in which the pattern 80 is photographed most greatly among the images of the photographed pattern 80. Thus, since the position and orientation of the stage 50 are detected based on the image in which the pattern 80 is photographed most greatly, the accurate position and orientation of the stage 50 can be detected more reliably.

<Third Embodiment>
FIG. 13 is a block diagram of main elements of the stage mechanism 30 according to the third embodiment. In FIG. 13, elements having the same functions and effects as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As illustrated in FIG. 13, the computer 75 includes a first calculation unit 91, a second calculation unit 92, a third calculation unit 93, a fourth calculation unit 94, a detection unit 95, a determination unit 96, and a stop. Part 99.

  If the determination unit 96 determines that the actual position and the control position are different, the determination unit 96 outputs a signal to the stop unit 99.

  The stop unit 99 receives the signal from the determination unit 96, that is, the position and posture of the stage 50 detected by the detection unit 95, and the control position and posture of the stage 50 derived from the rotation angle of each actuator 65. Are different from each other, the operation of each actuator 65 is stopped. Thereby, the drive of the stage 50 is also stopped.

  FIG. 14 is a flowchart of the process for detecting and correcting the position and orientation of the stage 50 in the stage mechanism 30 according to the present embodiment. Note that description of processing similar to that in the first embodiment is omitted.

  In step S90, when the determination unit 96 determines that the actual position and the control position do not match, the process proceeds to step S120. At this time, the determination unit 96 outputs a signal to the stop unit 99.

  In step S120, the stop unit 99 stops the operation of each actuator 65. As a result, the driving of the stage 50 is stopped. When the drive of the stage 50 is stopped, the computer 75 ends the detection process and stop process of the position and orientation of the stage 50.

  In the present embodiment, the computer 75 may further include a correction unit 97. In this case, when the determination unit 96 determines in step S90 that the actual position and the control position do not match, the determination unit 96 outputs a signal to the correction unit 97. In step S120, after the stop unit 99 stops the operation of each actuator 65, the correction unit 97 corrects the rotation angle of each actuator 65 so that the control position becomes the actual position. Thereby, for example, three-dimensional modeling on the stage 50 can be continuously performed.

  According to the stage mechanism 30 of the present embodiment, the computer 75 includes a stop unit 99 as shown in FIG. When the actuator 65 is composed of a stepping motor, for example, when the stepping motor steps out, there may be a difference between the control position and posture of the stage 50 and the actual position and posture of the stage 50. However, according to the above aspect, even when the stepping motor is out of step, the accurate position and orientation of the stage 50 can be detected, and the operation of the stepping motor is stopped by the stop unit 99 to drive the stage 50. Can be stopped. This is particularly effective when it becomes clear that an unexpected impact from the outside is applied to the stage 50 and the three-dimensional modeling on the stage 50 has failed.

  The embodiment of the present invention has been described above. However, the above-described embodiment is merely an example, and the present invention can be implemented in various other forms.

  In the embodiment described above, the pattern 80 is provided on the lower surface 50B of the stage 50, but may be provided on the upper surface 50U of the stage 50. In this case, the pattern 80 may be provided in a portion where the resin material discharged from the nozzle 22 of the modeling head 20 is not disposed. Further, the pattern 80 may be provided on a member attached to the stage 50. Thereby, the pattern 80 can be provided in the part where the resin material discharged from the nozzle 22 of the modeling head 20 is not disposed. Even if the arrangement of the pattern 80 is changed, the accurate position and orientation of the stage 50 can be reliably detected by calculation by considering the offset amount of the pattern 80 from the origin position defined in the above-described embodiment. Can do.

  In the embodiment described above, the camera 70 is disposed below the stage 50. However, as long as the pattern 80 provided on the stage 50 can be photographed, the camera 70 may be disposed above the stage 50. Alternatively, it may be arranged on the side of the stage 50. Thereby, the camera 70 can photograph the pattern 80 without being obstructed by the stage 50, the resin material disposed on the stage 50, and the rod 62. Even if the arrangement of the camera 70 is changed, the accurate position and orientation of the stage 50 can be reliably detected by considering the offset amount of the center 72C of the lens 72 of the camera 70.

  In the above-described embodiment, the stage mechanism 30 has been described as being used in the three-dimensional modeling apparatus 10, but is not limited thereto. The stage mechanism 30 may be used for a cutting machine, for example. In this case, the workpiece may be processed by attaching the processing tool to the stage 50, or the workpiece placed on the stage 50 may be processed by moving the stage 50 with respect to the fixed processing tool. .

  In the embodiment described above, the stage moving unit 60 drives the stage 50 with six degrees of freedom, but is not limited to this. A stage moving unit that drives the stage 50 with three, four, or five degrees of freedom may be used.

  In the embodiment described above, the origin position is that when the center 72C of the lens 72 of the camera 70 is disposed at the center of the first base 42 and the intersection 89C of the pattern 80 is provided at the center of the lower surface 50B of the stage 50. However, it is not limited to this. For example, the center 72C of the lens 72 may be disposed at a position shifted from the center of the first base 42, or the intersection 89C of the pattern 80 may be provided at a position shifted from the center of the lower surface 50B of the stage 50. Good. Even in such a case, the accurate position and posture of the stage 50 can be reliably detected by considering the offset amount with respect to the center 72C of the lens 72 and the intersection point 89C of the pattern 80.

  In the embodiment described above, the pattern 80 includes the first to fourth sub patterns 81 to 84 formed in a rectangular shape, and the stage mechanism 30 is a virtual circumscribing the first to fourth sub patterns 81 to 84. Although the quadrilateral 88 was provided, it is not limited to this. For example, as shown in FIG. 15, the stage mechanism 30 may include a triangular pattern 80 and a virtual quadrilateral 88 circumscribing the pattern 80. The virtual quadrangle 88 is similarly provided with four vertices 81T to 84T of the virtual quadrangle 88 shown in FIG. 5 and first to fourth lengths L1 to L4. When the line segment connecting the vertex 81T and the vertex 84T of the virtual quadrangle 88 is the first line segment 89A and the line segment connecting the vertex 82T and the vertex 83T is the second line segment 89B, An intersection 89C between the line segment 89A and the second line segment 89B is a reference point indicating the position and posture of the stage 50. As shown in FIG. 16, the stage mechanism 30 may include a circular pattern 80 and a virtual quadrilateral 88 circumscribing the pattern 80. The virtual quadrangle 88 is similarly provided with four vertices 81T to 84T of the virtual quadrangle 88 shown in FIG. 5 and first to fourth lengths L1 to L4. When the line segment connecting the vertex 81T and the vertex 84T of the virtual quadrangle 88 is the first line segment 89A and the line segment connecting the vertex 82T and the vertex 83T is the second line segment 89B, An intersection 89C between the line segment 89A and the second line segment 89B is a reference point indicating the position and posture of the stage 50.

  The terms and expressions used herein are used for explanation and are not used for limited interpretation. It should be recognized that any equivalents of the features shown and described herein are not excluded and that various modifications within the claimed scope of the invention are permitted. The present invention can be embodied in many different forms. This disclosure should be regarded as providing embodiments of the principles of the invention. The embodiments are described herein with the understanding that the embodiments are not intended to limit the invention to the preferred embodiments described and / or illustrated herein. It is not limited to the embodiment described here. The present invention also encompasses any embodiment that includes equivalent elements, modifications, deletions, combinations, improvements and / or changes that may be recognized by those skilled in the art based on this disclosure. Claim limitations should be construed broadly based on the terms used in the claims and should not be limited to the embodiments described herein or in the process of this application.

30 stage mechanism 40 base 50 stage 60 stage moving unit 70 camera 75 computer 80 pattern 95 detecting unit

Claims (11)

Base and
A stage provided with a mark, and a stage supported movably on the base;
A stage moving unit for driving the stage;
A photographing device for photographing the pattern provided on the stage;
A detection device that detects the position and orientation of the stage based on the image of the pattern imaged by the imaging device;
A virtual quadrilateral circumscribing the pattern ,
A stage mechanism in which the pattern varies depending on the position and posture of the stage when the pattern is viewed from the photographing apparatus. The pattern includes first to fourth rectangular sub-patterns each having a long side of the same length and a short side of the same length,
The mark is formed on any one of the first to fourth sub-patterns,
In the virtual quadrilateral, one vertex of each of the first to fourth sub-patterns is defined as first to fourth vertices,
The first to fourth sub-patterns are arranged inside the virtual quadrilateral,
The first sub-pattern and the second sub-pattern are spaced apart from each other in a direction in which a long side of the first sub-pattern and a long side of the second sub-pattern extend, and the first sub-pattern And the third sub-pattern are spaced apart from each other in a direction in which the short side of the first sub-pattern and the short side of the third sub-pattern extend, and the third sub-pattern and the fourth sub-pattern The pattern is spaced apart in the direction in which the long side of the third sub-pattern and the long side of the fourth sub-pattern extend, and the second sub-pattern and the fourth sub-pattern are the second sub-pattern The stage mechanism according to claim 1 , wherein a short side of the sub-pattern and a short side of the fourth sub-pattern are spaced apart from each other in the extending direction. The stage moving unit is configured to drive the stage with six degrees of freedom,
The detection device includes:
A first calculator that detects the mark from the image of the pattern photographed by the photographing device, and calculates a rotation angle of the stage around the Z axis based on the position of the detected mark;
In the image of the pattern photographed by the photographing device, a first length from the first vertex to the second vertex, a second length from the third vertex to the fourth vertex, and A second calculator that calculates a third length from the first vertex to the third vertex and a fourth length from the second vertex to the fourth vertex;
A third calculator for calculating a rotation angle around the X axis of the stage from a ratio between the first length and the second length;
A fourth calculation unit for calculating a rotation angle around the Y axis of the stage from a ratio between the third length and the fourth length;
Based on the calculated rotation angle around the X axis, rotation angle around the Y axis, and rotation angle around the Z axis, the attitude of the stage is detected, and the calculated rotation angle around the X axis, Y axis The first vertex and the fourth vertex based on the rotation angle around the rotation axis, the rotation angle around the Z-axis and the first to fourth lengths, and the first to fourth lengths calculated at the origin position A detection unit that detects an intersection of a first line segment connecting the second line segment and the second line segment connecting the second vertex and the third vertex as a position of the stage. 2. The stage mechanism according to 2 . The stage moving unit is
First to sixth guide portions that can be raised and lowered;
First to sixth actuators for raising and lowering the first to sixth guide parts, respectively;
First to sixth rods having one end connected to the stage via a first universal joint and the other end connected to the first to sixth guide parts via a second universal joint, The stage mechanism according to claim 3 provided. The stage mechanism according to claim 4 , wherein the photographing apparatus is disposed below the stage. The detection device includes:
Judgment to determine whether the position and posture of the stage detected by the detection unit and the control position and posture of the stage derived from the rotation angles of the first to sixth actuators match. And
The determination unit determines that the position and posture of the stage detected by the detection unit are different from the control position and posture of the stage derived from the rotation angles of the first to sixth actuators. And the control position and orientation of the stage derived from the rotation angle of the first to sixth actuators are the position and orientation of the stage detected by the detection unit. The stage mechanism according to claim 4 , further comprising: a correction unit that corrects the rotation angle of the actuator. The detection device includes:
Judgment to determine whether the position and posture of the stage detected by the detection unit and the control position and posture of the stage derived from the rotation angles of the first to sixth actuators match. And
The determination unit determines that the position and posture of the stage detected by the detection unit are different from the control position and posture of the stage derived from the rotation angles of the first to sixth actuators. The stage mechanism according to claim 4 , further comprising: a stop unit that stops the operation of the first to sixth actuators. The photographing apparatus is composed of two or more cameras,
The stage mechanism according to any one of claims 1 to 7 , wherein each of the cameras captures the pattern from different positions. When the pattern is captured by at least two or more of the cameras, the detection device detects the stage based on an image of the captured pattern that is the largest image. The stage mechanism according to claim 8 , wherein the position and posture are detected. Base and
A stage provided with a pattern and supported movably on the base;
A stage moving unit for driving the stage;
A photographing device for photographing the pattern provided on the stage;
A detection device that detects the position and orientation of the stage based on the image of the pattern imaged by the imaging device;
When viewing the pattern from the imaging device, the pattern varies depending on the position and orientation of the stage,
The photographing apparatus is composed of two or more cameras,
Each of the cameras captures the pattern from different positions,
When the pattern is captured by at least two or more of the cameras, the detection device detects the stage based on an image of the captured pattern that is the largest image. A stage mechanism that detects the position and orientation of the robot. It is a three-dimensional modeling apparatus that three-dimensionally models a modeled article by curing a resin material and sequentially laminating a resin having a predetermined cross-sectional shape,
A stage mechanism according to any one of claims 1 to 10,
A modeling head provided above the base and provided with a nozzle for discharging a resin material,
The resin material discharged from the nozzle is held on the upper surface of the stage,
The pattern is provided on the lower surface of the stage,
The photographing apparatus is a three-dimensional modeling apparatus disposed below the stage.

Images