JPH07290379A - Robot device - Google Patents

Abstract

PURPOSE:To continuously gain access to a work at an optimum angle in the optical direction by providing a control means concurrently driving a ringlike frame and multiple shafts of a robot and controlling the position and attitude of the tip of the robot. CONSTITUTION:A ringlike frame 10 is connected to a rotary shaft 12 turning the frame 10, and it is turned by an optional angle theta1 by a rotary mechanism 13 rotating the rotary shaft 12. The substrate section 21 of an articulated robot 20 is fitted at the prescribed position of the rotating portion of the ringlike frame 10, and it can be rotated by an optional angle theta3 centering on the axis 22. The articulated robot 20 is provided with three rotary shafts 23, 24, 25 rotated by optional angles theta4-theta6 respectively, and a heat machining head 26 such as a plasma torch is fitted at the tip. A controller concurrently drives all six shafts to control the heat machining head 26 at the prescribed position and attitude.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot device,
In particular, the present invention relates to a robot apparatus for cutting, punching, and forming a work such as an H-shaped steel or a square pipe from the periphery thereof.

[0002]

2. Description of the Related Art Generally, an articulated robot has a link-like structure in which each arm is directly connected by a joint made of a metal square pipe or the like. When machining steel materials such as H steel with such a robot, in order to access a plurality of surfaces of the steel material, two robots equipped with cutting tools are arranged on both sides in the width direction of the steel material. It is common practice to carry out processing or to arrange a robot on a traveling shaft mounted on the ceiling.

However, the method of using two robots has problems in terms of installation area, cost, interference between robots, and the method of mounting the traveling shaft on the ceiling has problems.
It is difficult to machine a work from the bottom surface direction, and the ceiling traveling axis becomes quite large in order to secure sufficient accuracy and size of the work.

Therefore, in the technique disclosed in Japanese Patent Laid-Open No. 1-88287, a robot for adjusting the rotation control elements provided on the four sides of a rectangular parallelepiped electronic device is supported by appropriate supporting means. Around a target object such as an electronic device, a ring-shaped member that can rotate and move in the front-back direction is arranged, and a hand in which a tool such as a driver is attached to the ring-shaped member is provided.
This hand is made movable in the tangential direction and the normal direction of the ring-shaped member.

In Japanese Patent Laid-Open No. 5-77078, a belt conveyor on which H steel is placed is provided across a gate type frame, and a laser processing head is arranged on the gate type frame to perform the laser processing. The head is configured to be movable in the XYZ directions, and the tip of the laser processing head is configured to be swingable so as to be oriented in the longitudinal direction, the height direction and the width direction of the H steel.

[0006]

[Patent Document 1] Japanese Patent Application Laid-Open No. 1-882
In the technique described in Japanese Patent Publication No. 87, it is possible to access each surface of the entire circumference of the work, but since the attitude control of the tool is not performed, the angle of the tool cannot be arbitrarily and continuously changed.

Further, in the technique described in the above-mentioned Japanese Patent Laid-Open No. 5-77078, since a gate type frame is used, it is not possible to access from below the work. It cannot be applied to machining that requires continuous machining of the entire circumference. Further, this conventional technique has a drawback in that it is impossible to continuously access the tool while arbitrarily changing the angle of the tool with respect to a plurality of surfaces.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a robot apparatus capable of continuously accessing a work in a wide range of movement from an arbitrary direction and an arbitrary angle. To aim.

[0009]

According to the present invention, a ring-shaped frame which rotates around a central axis, a robot which is attached to the ring-shaped frame and has a plurality of rotating shafts or moving shafts, and these ring-shaped frames are provided. And a control means for controlling the position and orientation of the tip of the robot by simultaneously driving and controlling a plurality of axes of the robot.

[0010]

According to the present invention, the articulated robot having a plurality of axes is attached to the rotating ring-shaped frame, and the plurality of axes of the ring-shaped frame and the robot are simultaneously controlled.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings.

FIG. 2 shows a die steel machining system to which the robot apparatus according to the present invention is attached. In this embodiment, the robot apparatus according to the present invention is subjected to thermal machining of the die steel to cut, punch, and groove. It is designed to be used as a die steel processing machine 1.

In FIG. 2, 1 is a die-casting machine in which a thermal processing head such as a plasma torch is attached to the end of a robot arm, 2 is a roller conveyor as a work table for carrying a work 3, 3 is square pipe steel, and angle steel. , C
A work such as a mold steel, 4 is an original size measuring device for measuring the size of the work, 5 is a work transfer mechanism, 6 is a dust collector, 7 is a plasma power supply, and 8 is a controller.

In the roller conveyor 2, during heat processing, there is interference with the heat flow from the heat processing head of the die steel processing machine 1, interference with various parts of the robot apparatus, removal of cutting waste materials, etc.
The vicinity of the die-steel processing machine 1 can be retracted downward.

After the work 3 is placed on the work transfer mechanism 5, it is moved in the X direction and transferred onto the roller conveyor 2. The work 3 placed on the roller conveyor 2 is moved in the Y direction by an appropriate configuration (not shown), and then X-
By being positioned in the Y direction, it is positioned at a predetermined processing position.

Although the details of the steel mold processing machine 1 will be described later, a robot having at least four axes is attached to a ring-shaped frame 10 arranged so as to surround the roller conveyor 2, and the ring-shaped frame 10 and The tip of the thermal processing head is controlled to an arbitrary position and posture by rotating or moving each axis of the robot. The controller 8 controls the position and attitude of the steel mold working machine 1. The diameter of the ring-shaped frame 10 is the same as that of the ring-shaped frame 1.
It is determined that the frame 10 does not interfere with the roller conveyor 2 or the work 3 by the rotation of 0.

When the machining of the same position in the Y direction is completed by the die-steel processing machine 1, the work 3 is conveyed in the Y direction by the roller conveyor 2 and the work is positioned at the next processing position in the same manner as described above, and then the heat is applied. Perform processing. Such processing is repeatedly executed.

FIGS. 1, 3 and 4 show a first embodiment of the steel mold working machine 1, in which a 4-axis articulated robot 20 is attached to a ring-shaped frame 10. The ring-shaped frame 10 rotates (θ2 in FIG. 3) and swivels (see FIG. 3).
.Theta.1), the model steel processing machine 1 has six axes in addition to the four-axis articulated robot 20.

As shown in FIG. 3, the ring-shaped frame 10 is arranged so that its circumferential surface is set on the frame surface S2. The frame surface S2 is arranged perpendicular to the surface S1 on which the die-steel processing machine 1 is installed (this is referred to as a reference surface) and the transport direction Y0 of the work 3.

The central axis c of the ring-shaped frame 10 is set to be perpendicular to the frame surface S2 and parallel to the reference surface S1. The ring-shaped frame 10 is rotationally driven about the central axis c by a rotating mechanism 11 including a motor and gears. The rotation angle is θ2.

The ring-shaped frame 10 is connected to a swivel shaft 12 that swivels the frame 10, and the swivel shaft 12 rotates.
An arbitrary angle θ1
It is designed so that it can be turned only (see FIG. 3). A frame surface S2 'shown by a broken line in FIG. 3 is a surface obtained by turning the frame surface S2 in the initial state by an angle θ1. That is, the central axis c of the ring-shaped frame 10 is always parallel to the reference plane S1, but the direction can be changed by an arbitrary angle θ1 with respect to the work transfer direction Y0 by turning by the rotating mechanism 13.

As shown in FIG. 1, when the turning shaft 12 is not in the center position of the ring-shaped frame 10 but in the X direction, the turning shaft 12 alone supports the weight of the entire processing machine. Since it may be difficult in terms of rigidity, install an arc-shaped support guide rail 14 on the floor,
The frame 10 may be supported from the opposite side by the rails 14, and the ring-shaped frame 10 may be rotated along the rails 14.

As the ring-shaped frame 10, for example,
A ring-shaped swing circle may be attached to the inner peripheral surface of the ring-shaped frame, or a guide rail or a rack may be provided on the inner peripheral surface of the ring-shaped frame.

The articulated robot 20 has a base portion 21 attached to a predetermined position of a rotating portion of the ring-shaped frame 10 and is configured to be rotatable about an axis 22 by an arbitrary angle θ3. The rotating shaft 22 is arranged parallel to the central axis c of the ring-shaped frame 10.

The remaining three axes of the multi-joint robot 20 have joint configurations similar to those of a normal robot arm, and are arranged in the directions shown in FIG. 3 and rotate about arbitrary angles θ4 to θ6 respectively. 24 and 25, and a thermal processing head 26 such as a plasma torch is attached to the tip thereof. In this case, the number of axes of the articulated robot 20 is
As described above, the number is four, including the base portion 21.

Incidentally, by appropriately setting the length d7 of the base portion 21, the ring-shaped frame 10 and the robot 2
It is possible to avoid interference with each unit of 0.

In this axis configuration, the controller 8
Drives and controls all six axes simultaneously in order to control the thermal processing head 26 to a predetermined position and posture.

The dimensions of each part and the angle of each axis are shown in FIG.
When set as shown in FIG. 4, the coordinate conversion formula of each axis and the tip of the tool becomes as shown in << Formula 1 >>. All formulas in the specification are listed at the end of the specification.

Assuming that the position and orientation of the tool tip is PB, the relationship between PB and the coordinate conversion formula 1 is as shown in <Formula 2>.

In this way, when the position and orientation PB of the tool tip are obtained, the axes are converted into angles θ1 to θ6 of each axis as in << Equation 3 >> to << Equation 5 >>. The command values θ1 to θ6 for

In addition, in << Equation 3 >> to << Equation 5 >>, each symbol is defined as follows.

Pw and PB are matrices representing the position and orientation of the wrist base and tool tip as viewed from the base coordinate system, and aw = (awx, awy, awz), a = (ax, ay, a).
z) is the approach vector of the wrist base and tool tip, respectively, ow = (owx, owy, owz), o = (ox, oy,
oz) is the direction vector of the wrist root and the tool tip, respectively, nw = (nwx, nwy, nwz), n = (nx, ny,
nz) is a normal vector in which each of the three vectors forms a right-handed system (nw = ow × aw, n = o ×).
a).

Further, pw = (pwx, pwy, pwz) is the position vector of the wrist base, and p = (px, py, pz) is the position vector of the tool tip.

The above is illustrated in FIG.

Next, FIGS. 6 and 7 show a second embodiment of the steel mold working machine 1.

In the second embodiment, the robot attached to the ring-shaped frame 10 is a 5-axis articulated robot, and the rotary shaft 31 of the ring-shaped frame 10 is used.
Is basically fixed.

That is, the second embodiment is to be applied when a large operation range is not required in the work transfer direction, and the rotation of the ring-shaped frame 10 by the rotation shaft 31 that causes a large load is eliminated, and the robot is operated. By using a 5-axis articulated robot, the positioning accuracy and operation speed are improved.

FIG. 7 shows the details of the shaft configuration. The first shaft 31 for turning having a rotation angle of θ1 fixes the angle θ1 to a constant angle by, for example, matching the cutting angle.
The other 6 axes 32 to 37 (rotational angles θ2 to θ7) are simultaneously driven and controlled by the controller 8.

Here, the dimensions of each part and the angle of each axis are shown in FIG.
When set as shown in, the coordinate conversion formula of each axis and the tip of the tool is as shown in <Formula 6>.

Assuming that the position and orientation of the tool tip is PB, the relationship between PB and the above coordinate conversion equation 6 is as shown in << Equation 7 >>.

When the position and the attitude PB of the tool tip are obtained as described above, they are converted into the angles θ2 to θ7 of the respective axes as in << Equation 8 >> to << Equation 10 >>.
Command values θ2 to θ7 for each axis are obtained.

It should be noted that in << Equation 8 >>, Pw is a matrix representing the position and orientation of the wrist base viewed from the base coordinate system, whereas Pw ′ is the position of the wrist base viewed from the uniaxial coordinate system. , Is a matrix representing the posture.

FIG. 8 and FIG. 9 show a third embodiment of the die steel working machine 1.

In the third embodiment, as in the second embodiment, the robot mounted on the ring-shaped frame 10 is a five-axis articulated robot, and the turning shaft 31 of the ring-shaped frame 10 is basically fixed. I am trying.

That is, the third embodiment should also be applied when a large movement range is not required in the work transfer direction, and the rotation of the ring-shaped frame 10 by the rotation shaft 31 that causes a large load is eliminated, and the robot is operated. By using a 5-axis articulated robot, the positioning accuracy and operation speed are improved.

FIG. 9 shows the details of the shaft configuration. The first shaft 61 (turning shaft θ0) is fixed at a predetermined angle, and the second shaft 6 is fixed.
By simultaneously driving the second to seventh axes 67 (θ1 to θ6) under the control of the controller 8, the position and attitude of the torch tip are controlled.

The difference between the third embodiment and the second embodiment is 5
It is only how to attach the third shaft 63 and the fourth shaft 64 of the multi-axis robot.

Here, the dimensions of each part and the angle of each axis are shown in FIG.
By setting as shown in, the coordinate conversion formula of each axis and the tip of the tool becomes as shown in <Formula 11>.

Assuming that the position and orientation of the tool tip is PB, the relationship between PB and the coordinate conversion formula 11 is as shown in <Formula 12>.

When the position and the posture PB of the tool tip are obtained as described above, the equations 13 to 15 are used.
By converting the angles θ1 to θ6 of each axis as described above, the command values θ1 to θ6 for each axis are obtained.

FIG. 10 and FIG. 11 show a fourth example of the die-steel processing machine 1.
An example of is shown.

In the fourth embodiment, the pivot of the ring-shaped frame is basically fixed as in the second embodiment, and the base portion 21 of the robot attached to the ring-shaped frame 10 is fixed to the frame 10. It is configured so as to be slidable in the axial direction, that is, in the work transfer direction (direction of arrow F), and the same four-axis articulated robot as in the first embodiment is arranged on the base portion 21. .

That is, in FIG. 11, the first shaft (turning shaft) 41 is fixed at a predetermined angle, and the second shaft 42 to the seventh shaft 47 (θ2 to θ7) are driven simultaneously by the control of the controller 8. Controls the position and attitude of the torch tip.

In the fourth embodiment, the formula for obtaining the command value is basically the same as the above, and the disclosure thereof is omitted for convenience.

FIG. 12 and FIG. 13 show the fifth example of the steel mold working machine 1.
An example of is shown.

In the fifth embodiment, the rotary shaft 50 of the ring-shaped frame 10 is basically fixed as in the previous second to fourth embodiments, and the base portion of the robot attached to the ring-shaped frame 10 is basically fixed. 21 is configured to be slidable in the radial direction of the frame 10 (direction of arrow G), and the base portion 21 is provided with the same 4 as in the first embodiment.
An axis articulated robot is arranged.

That is, in FIG. 13, the first axis (swivel axis θ0) 50 is fixed at a predetermined angle, and the second axis 51 to the seventh axis 56 (θ1 to θ6) are simultaneously driven under the control of the controller 8. Controls the position and orientation of the torch tip.

Here, the dimensions of each part and the angle of each axis are shown in FIG.
When set as shown in Fig. 3, the coordinate conversion formula for each axis and the tool tip is << Equation 16 >>, where PB is the position and orientation of the tool tip, the relation between PB and the coordinate conversion equation 16 is as shown in become.

When the position and the posture PB of the tool tip are obtained as described above, the equations 18 to 20 are used.
By converting the angles θ1 to θ6 of each axis as described above, the command values θ1 to θ6 for each axis are obtained.

In each of the above embodiments, the ring-shaped frame 10 is swung by the swivel axis parallel to the Z direction, but the ring-shaped frame 10 may be slid along the work transfer direction. .

Further, in the embodiment, the robot apparatus of the present invention is used as a steel mold working machine, but the present invention may be applied to any other technique.

<< Equation 1 >> << Equation 2 >> PB = A1, A2, A3, A4, A5, A6, At << Equation 3 >> << Equation 4 >> << Equation 5 >> << Equation 6 >> << Equation 7 >> PB = A1, A2, A3, A4, A5, A6, A7, A
t << formula 8 >> << Equation 9 >> << Equation 10 >> << Equation 11 >> << Equation 12 >> PB = A1, A2, A3, A4, A5, A6, At << Equation 13 >> << Equation 14 >> << formula 15 >> << formula 16 >> << Equation 17 >> PB = A1, A2, A3, A4, A5, A6, At << Equation 18 >> << formula 19 >> << Equation 20 >>

[0063]

As described above, according to the present invention,
Since a multi-joint robot having a plurality of axes is attached to a rotating ring-shaped frame and the position and the posture of the robot tip are controlled by simultaneously controlling the plurality of axes of the ring-shaped frame and the robot, The movement range can be increased, and the work can be continuously accessed from any direction at any angle.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a die steel processing system to which the present invention is applied.

FIG. 3 is a diagram showing a shaft configuration of the first embodiment.

FIG. 4 is a diagram showing dimensions of each part of the first embodiment.

FIG. 5 is a diagram for explaining each symbol used in the formula.

FIG. 6 is a perspective view showing a second embodiment of the present invention.

FIG. 7 is a diagram showing a shaft configuration of a second embodiment.

FIG. 8 is a perspective view showing a third embodiment of the present invention.

FIG. 9 is a diagram showing a shaft configuration of a third embodiment.

FIG. 10 is a perspective view showing a fourth embodiment of the present invention.

FIG. 11 is a diagram showing a shaft configuration of a fourth embodiment.

FIG. 12 is a perspective view showing a fifth embodiment of the present invention.

FIG. 13 is a diagram showing a shaft configuration of a fifth embodiment.

[Explanation of symbols]

 1 ... Shape steel processing machine 2 ... Roller conveyor 3 ... Work 4 ... Actual size measuring device, 5 ... Work transfer mechanism 6 ... Dust collector 7 ... Plasma power supply 8 ... Controller 10 ... Ring frame

Claims (5)

[Claims] 1. A ring-shaped frame that rotates around a central axis, a robot that is attached to the ring-shaped frame and has a plurality of rotation axes or moving axes, and a ring-shaped frame and a plurality of axes of the robot that are simultaneously provided. A robot apparatus comprising: a control unit that controls driving and controls the position and orientation of the tip of the robot. 2. The robot apparatus according to claim 1, wherein the robot has at least three degrees of freedom, and the ring-shaped frame has a turning axis for changing an angle of a central axis thereof in a horizontal direction. 3. The robot apparatus according to claim 1, wherein the robot has at least four degrees of freedom. 4. The robot apparatus according to claim 1, wherein said robot is slidably attached to said ring-shaped frame in a direction parallel to its central axis and has a joint having at least three degrees of freedom. 5. The robot apparatus according to claim 1, wherein the robot is slidably attached to the ring-shaped frame in a radial direction thereof and has a joint having at least three degrees of freedom.