JP3577296B2 - Method and device for setting motion path of articulated robot - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for setting an operation path of an articulated robot, and more particularly to an end effector provided at the tip of the articulated robot for setting a path for operating from a predetermined starting point to a destination. And an apparatus for setting an operation path of an articulated robot.
[0002]
[Prior art]
Conventionally, when teaching a work posture by directly operating an articulated robot installed on a production line, an operator who is familiar with the operation of the articulated robot must perform work at the production line site. The work becomes inefficient. Further, the operation must be performed in a state where the production line is stopped, so that the operation rate of the production line is also reduced.
[0003]
Therefore, in recent years, offline teaching (offline teaching) has been performed in order to improve the efficiency of the teaching operation or to improve the operation rate of the manufacturing line. That is, a multi-joint robot and a model of a work and a peripheral structure which are work objects are constructed on a computer, teaching data is created using the model, and then the teaching data is supplied to a multi-joint robot at the site. In this case, there is no need to stop the production line while creating teaching data.
[0004]
[Problems to be solved by the invention]
By the way, the offline teaching according to the prior art is not always widely used.
[0005]
This is because it is necessary for the articulated robot to avoid interference (contact, etc.) with various peripheral structures, works, and the like, but when there are many types of peripheral structures and the shape of the work is complicated. This is because, in some cases, it is difficult to set an operation path that avoids those obstacles.
[0006]
More specifically, the brute force method of investigating interference for all possible postures of the articulated robot is not practical because of the large amount of calculation, and optimization methods such as so-called mathematical programming require solutions. May not exist. Furthermore, the stochastic method using random numbers has problems that there is no guarantee that the solution converges and that there is no reproducibility of calculation.
[0007]
Several approaches have been proposed to solve these problems.
[0008]
For example, there is a method using a plane including a start point and a destination point (see Japanese Patent No. 2875498). In this method, an entry-prohibited area in which the cross section of an obstacle is appropriately enlarged on a specified plane is defined, and an operation path passing through the vertex of the entry-prohibited area is set to avoid interference. However, in this method, since the interference with the no-go area is verified each time to set the operation path, the verification work becomes complicated and the operation path becomes complicated. Furthermore, even if the motion path is proper, it cannot be verified from the viewpoint of the motion range of each axis whether or not the articulated robot can actually move on the motion path.
[0009]
As another method, for example, there is a method of inputting and instructing the position and shape of an obstacle with a dedicated controller at a production site to set an operation path (see Japanese Patent Application Laid-Open No. 9-81228). However, in this method, since the teaching is performed while operating the actual machine at the production site, the operation path cannot be automatically set.
[0010]
The present invention has been made in consideration of such problems, and automatically and efficiently calculates the operation path of the articulated robot without performing complicated calculations affected by the shapes of works and obstacles. It is an object of the present invention to provide a method and a device for setting an operation path of an articulated robot capable of setting.
[0011]
[Means for Solving the Problems]
The motion path setting method of the articulated robot according to the present invention, in the motion path setting method of the articulated robot that moves the end effector from the starting point to the destination, assuming a path connecting the starting point and the destination, A first step of examining whether or not the end effector can be operated on the path; and in the first step, when it is impossible to operate on the path, Start the end effector from the starting point or the destinationA predetermined position based on the attitude of the end effector at the start point or the arrival point.A second step of setting an evacuation route that operates only a specified distance in the direction.
[0012]
This allows the end effectorPredeterminedSince the specified motion of moving in the direction by the specified distance is applied, the motion path of the articulated robot is automatically and efficiently set without performing complicated calculations that are affected by the shape of the work or obstacle. be able to.
[0013]
Here, the articulated robot and the end effector are virtual ones configured as models by computer program processing.
[0014]
Also,In the second step, when it is impossible to operate the end effector on the path, a third step of setting a retreat path for operating the end effector by a specified distance in a direction of a fixed point in space is provided. Good.
[0015]
As a result, the specified operation of moving the end effector in the direction of the fixed point by the specified distance is applied, so that the operation path of the articulated robot can be calculated without complicated calculations affected by the shape of the workpiece or obstacle, and , Can be set automatically and efficiently.
[0016]
Further, the fixed point may be a center point of an original axis of the articulated robot.
[0017]
Furthermore,After the third step,The end point of the evacuation route is defined as a new starting point or a destination point, and the first step and the3May be executed again.
[0018]
When the end point is a point at which the articulated robot is unreachable or a point at which interference occurs, the refuge route with the specified distance corrected may be reset.
[0019]
The motion path setting device for a multi-joint robot according to the present invention is a motion path setting device for a multi-joint robot that moves an end effector from a start point to a destination point, and assumes a path connecting the start point and the destination point. However, the route investigation unit that investigates whether or not the end effector can be operated on the route and the route investigation unit determine that it is impossible to operate the route on the route. In the case, a path setting unit that sets a retreat path that operates the specified distance from the starting point or the reaching point in the end effector in a predetermined direction based on the attitude of the end effector at the starting point or the reaching point. Characterized by having.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a method and an apparatus for setting a motion path of an articulated robot according to the present invention will be described with reference to FIGS.
[0021]
The method and the apparatus for setting the motion path of the articulated robot according to the present embodiment basically include a template operation for moving an end effector provided at the tip of the articulated robot by a specified distance from a starting point in a specified direction. And sets an operation route for moving to a destination while avoiding an obstacle.
[0022]
As shown in FIG. 1, an off-line teaching device (movement path setting device) 10 used in the present embodiment is for teaching the operation of the articulated robot 50, and is assigned to a work target based on the created teaching data. On the other hand, it is linked to a robot device 12 that performs a desired operation.
[0023]
The robot device 12 includes an articulated robot 50 and a robot control unit 22 that controls the operation of the articulated robot 50 based on the teaching data.
[0024]
As shown in FIG. 2, the control unit 14 configuring the offline teaching device 10 includes a CPU (computer) 26 as control means for controlling the entire offline teaching device 10, a ROM 28 and a RAM 29 as storage units, and a hard disk. A hard disk drive (HDD) 39 for accessing data to the display 34; a drawing control circuit 30 for performing drawing control on the screen of the monitor 16; and an interface circuit 32 to which the keyboard 18 and the mouse 20 as input devices are connected. A recording medium drive 36 for controlling an external recording medium 36a (for example, a flexible disk or a compact disk), a data generation circuit 38 for generating teaching data, and a system for performing simulation on the screen of the monitor 16 based on the teaching data. And an Interview configuration circuit 40. The simulation circuit 40 is based on three-dimensional CAD and has a function of creating the model and investigating interference between the models.
[0025]
The hard disk 34 stores an operation path setting program 35 having a function of setting the operation path of the articulated robot 50, condition data 37 as conditions for setting the operation path, an OS (not shown), and the like.
[0026]
The operation path setting program 35 includes a path investigation unit 35a that investigates whether or not the gun unit (end effector) 68 (see FIG. 3) can be operated on a path connecting any two points, And a route setting unit 35b for setting and applying the first and second template operations to be performed.
[0027]
As shown in FIG. 3, the articulated robot 50 includes a second base 56, a first link 58, a second link 60, and a third link with respect to a first base 54, which is a mounting base, in the order toward the distal end. 62, the fourth link 64 and the gun attaching / detaching portion 66 are connected. The gun unit 68 is connected to the gun attaching / detaching portion 66 at the tip.
[0028]
The second base 56 is rotatably supported on the first base 54 about an axis J1 that is a vertical axis. The base end of the first link 58 is supported by the second base 56 so as to be able to descend on an axis J2 which is a horizontal axis. The proximal end of the second link 60 is pivotally supported by the distal end of the first link 58 by an axis J3 which is a horizontal axis. The third link 62 is connected to the distal end side of the second link 60 using the axis J4 as a common rotation center axis. Further, the base end of the fourth link 64 is pivotally supported on the distal end of the third link 62 by an axis J5 perpendicular to the axis J4. The gun attaching / detaching portion 66 is connected to the distal end side of the fourth link 64 using the axis J6 as a common rotation center axis.
[0029]
The gun unit 68 connected to the gun attachment / detachment part 66 is a so-called C-type welding gun, and has a pair of electrodes 70 and 72 that open and close along the axis J6 at both ends of the arched arm 74. In a closed state, the electrodes 70 and 72 come into contact with the work 80 at a welding operation point (hereinafter, referred to as TCP (Tool Center Point)) on the axis J6.
[0030]
A direction that matches the axis of the electrode 72 on the main body side from the TCP is defined as a vector Zr, and a direction that is orthogonal to the vector Zr and faces outside the gun unit 68 is defined as a vector Xr. A direction orthogonal to the vector Xr and the vector Zr is defined as a vector Yr.
[0031]
The drive mechanism for the axes J1 to J6 and the opening and closing mechanism for the electrodes 70 and 72 are driven by actuators (not shown), and TCP is determined by the values of the rotation angles θ1 to θ6 of the axes J1 to J6 and the dimensions of each part of the articulated robot 50. It is determined.
[0032]
Further, the gun unit 68 is not limited to the C-type welding gun, and may be, for example, an X-type welding gun (a welding gun having a pair of openable and closable gun arms supported by a common support shaft) 68a shown in FIG.
[0033]
As a reference point for coordinate calculation and control of the articulated robot 50, a point at which the axis J1 and the axis J2 intersect is defined as an origin (center point of the original axis) O, and a vertical upward direction is defined based on the origin O. The direction of the axis J2 when the height Z and the rotation angle θ1 are θ1 = 0 is expressed as depth Y, and the direction perpendicular to the height Z and the depth Y is expressed as width X. The height Z, the width X, and the depth Y indicate three-dimensional orthogonal coordinates.
[0034]
Next, a procedure for setting an operation path of the articulated robot 50 using the offline teaching device 10 and the operation path setting program 35 configured as described above will be described with reference to FIGS.
[0035]
In the following description, as shown in FIG. 5, an example in which the gun unit 68 is operated from a certain starting point P1 to a reaching point P2 of a thin work 80 will be described. The starting point P1 and the arriving point P2 are composed of a total of six values of three parameters of three-dimensional orthogonal coordinate values (X, Y, Z) in a space where welding is performed and three parameters indicating the attitude of the gun unit 68. It is assumed that an obstacle 82 exists between the start point P1 and the destination point P2. It has been verified in advance that the gun unit 68 can reach the start point P1 and the arrival point P2, and the posture of the gun unit 68 when welding the start point P1 and the arrival point P2, that is, the vector Xr , Vector Yr and vector Zr are also determined.
[0036]
In addition, the starting point P1 and the reaching point P2 may be other than the welding point. For example, a position where the protrusion of the work 80 is avoided may be obtained in advance, and the points may be set as the starting point P1 and the reaching point P2.
[0037]
First, in step S1 of FIG. 6, the operator of the offline teaching device 10 starts the operation path setting program 35 by a predetermined operation method. The OS incorporated in the offline teaching device 10 loads the operation path setting program 35 stored in the hard disk 34 into the RAM 29 and executes it. The processing after the next step S2 is executed by the operation path setting program 35.
[0038]
In step S <b> 2, the operation path setting program 35 reads condition data 37, which is a condition for setting an operation path, from the hard disk 34 and stores the read condition data 37 in the RAM 29. Further, from the condition data 37, the starting point P1, the reaching point P2, the shape of the work 80, the position and the shape of the obstacle 82, etc., for which the motion path is to be set are recognized.
[0039]
Next, in step S3, assuming an operation path (path) 100 connecting the starting point P1 and the arrival point P2, whether or not the posture is established when the gun unit 68 is operated on the operation path 100 is determined. Investigate the presence and absence of interference.
[0040]
The motion path 100 may be a straight line as shown in FIG. 5 or an arbitrary curve that facilitates the operation of the articulated robot 50. The same applies to operation paths 102, 104, 110, and 112 described later.
[0041]
Specifically, a division point obtained by dividing the operation path 100 into minute lengths is assumed. Then, the posture of the articulated robot 50 when the gun unit 68 is arranged at each of the division points, that is, the rotation angles θ1 to θ6 are obtained. The method of calculating the rotation angles θ1 to θ6 is a total of six values defined by the position coordinates (X, Y, Z) of the division point in space and the vector Xr, vector Yr, and vector Zr representing the attitude of the gun unit 68. A well-known matrix calculation method (hereinafter, referred to as an inverse calculation) may be applied based on the size of each part of the articulated robot 50 and the like.
[0042]
When the posture of the gun unit 68 at the start point P1 and the arrival point P2 is different, a vector Xr, a vector Yr, and a vector Zr indicating the posture of the gun unit 68 at each division point may be linearly complemented. In this investigation, the electrodes 70 and 72 are treated as an open state so that the electrodes 70 and 72 do not interfere with the work 80.
[0043]
If the posture of the articulated robot 50 is established at each division point, the operation from the start point P1 to the destination point P2 is actually guaranteed.
[0044]
Next, in step S4, it is determined whether the solution of the inverse operation has been normally obtained at each division point, that is, whether the TCP can reach the division point. If a solution is not obtained, or even if the angle value is out of the rotation operation range of the axes J1 to J6, or if the articulated robot 50 interferes with the obstacle 82 or the like in the determined posture. The process moves to step S5, and in other cases, that is, if the solution is normally obtained, an end process is performed in step S29.
[0045]
The presence or absence of the interference may be determined by using the function of the simulation circuit 40 regarding the interference.
[0046]
In step S5 in FIG. 7, in order to avoid the obstacle 82 or establish the posture, the gun unit 68 is applied with the first template operation from the start point P1 to the first relay point Q1 (new start point). Set.
[0047]
Here, the template represents a prescribed operation to be executed by the articulated robot 50, and the first template has a prescribed distance in a prescribed direction with respect to the TCP of the gun unit 68, as shown in FIG. This is an operation of assuming the operated first relay point Q1 to move the gun unit 68 to an operation path (backup path) 102 connecting the starting point P1 and the first relay point Q1. The first relay point Q1 is obtained by simply moving the position of the start point P1, and the direction of the gun unit 68 of the start point P1, that is, the direction of TCP is assumed to be unchanged.
[0048]
In general, the vector Zr is set so as to be perpendicular to the workpiece 80 in order to properly perform the welding operation. Therefore, it is preferable that the specified direction is the direction in which the gun unit 68 is pulled out, that is, the direction opposite to the vector Xr. It is. The prescribed distance may be a distance that can be sufficiently separated from the work 80 according to the size of the gun unit 68. 100 mm is suitable for a gun unit of a general size.
[0049]
The first template is an effective evacuation method for a thin plate that is a general work, and an operation path can be set by a predetermined simple evacuation method without being affected by the shape of the work. .
[0050]
Next, in step S6 of FIG. 7, whether or not the posture of the articulated robot 50 is established at the first relay point Q1 and whether or not there is interference with the surrounding obstacles 82 and the like are investigated in the same manner as in step S3.
[0051]
Next, in step S7, as a result of the investigation in step S6, if the posture of the articulated robot 50 at the first relay point Q1 is established and it can be determined that there is no interference, the process proceeds to step S12; otherwise, the process proceeds to step S8. Move on to
[0052]
In step S8, it is assumed that the gun unit 68 is rotated by a predetermined angle around the vector Xr, Yr or Zr in order to obtain an appropriate posture at the first relay point Q1. This rotation processing is performed together with step S9 as the next determination processing, and all the vectors Xr, Yr, and Zr are sequentially rotated.
[0053]
Next, in step S9, it is confirmed whether or not the integrated angle rotated by a predetermined angle has reached 360 °, and if it is less than 360 °, the flow proceeds to step S6 to determine the attitude of the articulated robot 50.
[0054]
If an appropriate posture cannot be obtained at the first relay point Q1 even after rotating the vector Xr, the vector Yr, and the vector Zr by 360 °, in step S10, the first relay point Q1 is moved to the starting point P1. The position is reset by a predetermined distance in the direction. That is, if the first relay point Q1 is set at a distance of 100 mm from the start point P1, the first relay point Q1 is returned by 10 mm in the direction of the start point P1 and reset to a position of 90 mm.
[0055]
Next, in step S11, the integrated value of the distance for returning the first relay point Q1 is checked, and when the distance has returned to the starting point P1, which is the initial point, the processing is interrupted and replanning is performed. . If it has not returned to the starting point P1, that is, if the first relay point Q1 is within a range of 10 to 90 mm from the starting point P1, the process proceeds to step S6, and the posture of the articulated robot 50 is determined.
[0056]
On the other hand, in step S12 (when the posture of the articulated robot 50 is established in step S7 and it is determined that there is no interference), the motion path 102 (see FIG. 4) connecting the first relay point Q1 and the starting point P1 Assuming that the gun unit 68 is operated on the operation path 102, an investigation as to whether or not the posture is established and whether or not there is interference is performed by the same processing as in step S3.
[0057]
Next, in step S13, the same determination as in step S4 is performed. When it is determined that the posture of the articulated robot 50 is established at the division point on the motion path 102 and the robot is operable, the process proceeds to the next step S14. . If it is determined that the operation is impossible, the process returns to step S10, and the position of the first relay point Q1 is further changed.
[0058]
In step S14, it is confirmed that two first relay points Q1 and first relay points Q2 (new destination points) have been set for the starting point P1 and the destination point P2, and the process proceeds to the next step S15. If the first relay point Q2 corresponding to the arrival point P2 has not been set, the process returns to step S5 in FIG.
[0059]
Next, in step S15, assuming an operation path 104 connecting the two first relay points Q1 and Q2, whether the posture is established and whether or not interference occurs when the gun unit 68 is operated on the operation path 104 is described. Is performed by the same processing as in step S3.
[0060]
Next, in step S16, the same determination as in step S4 is performed. When it is determined that the posture of the articulated robot 50 is established at the division point on the operation path 104 and the operation is possible, the operation is performed in step S29 in FIG. Performs route termination processing. If it is determined that the operation cannot be performed, the process proceeds to the next step S17.
[0061]
In step S17 in FIG. 8, in order to avoid the obstacle 82, the second relay point R1 is set by applying the second template operation from the first relay point Q1 to the gun unit 68.
[0062]
As shown in FIG. 9, the second template assumes a line 108 connecting the first relay point Q1 and a predetermined fixed point 106, and indicates a point moved on the line 108 by a specified distance from the first relay point Q1. This is the second relay point R1.
[0063]
The second relay point R1 is obtained by moving the first relay point Q1 by a position in space, and the direction of the gun unit 68 of the first relay point Q1, that is, the direction of TCP is assumed to be invariable.
[0064]
The second template is used as a free space in which the obstacle 82 is unlikely to exist in order to operate the gun unit 68 which has already separated from the work 80 in a direction where there is no obstructing obstacle 82. It is operated in the direction. That is, generally, there is no obstacle 82 that hinders the operation of the articulated robot 50 near the origin O, and there is a possibility that the obstacle 82 can be avoided by operating in this direction. It is high and suitable. The prescribed distance is preferably 100 mm.
[0065]
If there is a place where the obstacle 82 does not exist or a place where it is easy to operate other than the origin O as the fixed point 106, the place may be set as the fixed point 106. For example, when the motion range of the articulated robot 50 is expressed in space, it is considered that the degree of freedom of motion is the largest at the center position.
[0066]
Next, in step S18, whether or not the posture of the articulated robot 50 is established at the second relay point R1 and whether or not there is interference with surrounding obstacles 82 and the like are examined in the same manner as in step S3.
[0067]
Next, in step S19, as a result of the investigation in step S18, if the attitude of the articulated robot 50 at the second relay point R1 is established and it can be determined that there is no interference, the process proceeds to step S24. Move to S20.
[0068]
In step S20, in order to obtain an appropriate posture at the second relay point R1, as in step S8, it is assumed that the gun unit 68 is rotated by a predetermined angle around the vector Xr, Yr or Zr. .
[0069]
Next, in step S21, it is confirmed whether or not the integrated angle rotated by a predetermined angle has reached 360 °. If it is less than 360 °, the process proceeds to step S6, and the posture of the articulated robot 50 is determined.
[0070]
If an appropriate posture cannot be obtained at the second relay point R1 even when the vector Xr, the vector Yr, and the vector Zr are rotated by 360 °, in step S22, the second relay point R1 is moved in the direction of the fixed point 106. Is reset to the position moved by a predetermined distance. That is, if the second relay point R1 is set at a distance of 100 mm from the first relay point Q1, it is further moved by 100 mm in the direction of the fixed point 106 and reset to a position of 200 mm.
[0071]
Next, in step S23, the integrated value of the distance traveled by the second relay point R1 is checked, and when the distance reaches the fixed point 106, the process is interrupted and replanning is performed. If it has not reached the fixed point 106, the process proceeds to step S18, and the posture of the articulated robot 50 is determined.
[0072]
In step S24 (when the posture of the articulated robot 50 is established in step S19 and it is determined that there is no interference), an operation path 110 connecting the first relay point Q1 and the second relay point R1 is assumed, An investigation as to whether or not the posture is established and whether or not there is interference when the gun unit 68 is operated on the operation path 110 is performed by the same processing as in step S3.
[0073]
Next, in step S25, the same determination as in step S4 is performed. If it is determined that the posture of the articulated robot 50 is established at the division point on the operation path 110 and the operation is possible, the process proceeds to the next step S26. If it is determined that the operation is impossible, the process returns to the step S22 and the first step is performed. The position of the relay point Q1 is further changed.
[0074]
In step S26, it is confirmed that two second relay points R1 and R2 have been set for the first relay points Q1 and Q2, and the process proceeds to the next step S27. If the second relay point R2 corresponding to the first relay point Q2 has not been set, the process returns to step S17.
[0075]
Next, in step S27, an operation path 112 connecting the two second relay points R1 and R2 is assumed, and the operation on this operation path 112 is examined in the same manner as in step S3.
[0076]
Next, in step S28, the same determination as in step S4 is performed. If the posture of the articulated robot 50 is established at the division point on the operation path 112 and it can be determined that the operation is possible, the operation path end processing is performed. When it is determined that the operation cannot be performed due to the interference of the obstacle 82 or the like, the process returns to step S22, the two second relay points R1 and R2 are further moved, and the processing may be repeated until the operation path is established.
[0077]
After the setting of the motion path from the start point P1 to the destination point P2 is completed, an end process is performed in step S29 in FIG. As the end processing, for example, the set operation path is recorded in the path table 120 shown in FIG. The path table 120 is a table that records a set starting route, a starting point P1, a first relay point Q1, a second relay point R1, a second relay point R2, a first relay point Q2, and a destination point P2 in the order of operation. In addition, the position coordinates (X, Y, Z) at each point, the values of the vectors Xr, Yr, and Zr indicating the TCP and the values of the rotation angles θ1 to θ6 of the axes of the articulated robot 50 are recorded.
[0078]
The operation path recorded in the path table 120 is converted by the data creation circuit 38 into program data for operating the actual articulated robot 50, and then transferred to the robot controller 22.
[0079]
The path table 120 is recorded in the RAM 29 or the hard disk 34, but can be displayed on the screen of the monitor 16 or printed as necessary.
[0080]
In the above description, the operation route 104 is a route connecting the first relay points Q1 and Q2. However, the first relay point Q1 is obtained by applying the first template only to the starting point P1. The same may be applied to the arrival point P2, and a route connecting the first relay point Q1 and the arrival point P2 may be assumed.
[0081]
Similarly, for the operation route 112, for example, a route connecting the second relay point R1 and the first relay point Q1 may be assumed.
[0082]
The operation routes 102 and 110 as a refuge route for evacuating from the starting point P1 may be diverted when operating to a point other than the arrival point P2.
[0083]
Further, although the prescribed distance initially applied in the first template is 100 mm, the form may be extended from 20 mm to 30 mm starting from 10 mm.
[0084]
The order in which the first and second templates are applied may be reversed depending on the situation of the work 80, the obstacle 82, and the like.
[0085]
The set path table 120 indicates an operation path from the start point P1 to the destination point P2. This operation path is reversible, and is used as a path that operates from the arrival point P2 to the start point P1. Alternatively, instead of using the entire operation path, a path halfway may be used.
[0086]
Furthermore, the present embodiment can be applied to, for example, an assembling robot, a painting robot, and the like other than the welding robot, and the articulated robot 50 has a seven-axis structure, a link mechanism, and a telescopic mechanism. And the like.
[0087]
As described above, according to the present embodiment, first, an operation path 100 connecting the starting point P1 and the arrival point P2 is assumed, and it is determined whether the gun unit 68 can be operated on the operation path 100. Therefore, if the gun unit 68 can operate on the operation path 100, the operation path can be set extremely easily without providing a relay point for the operation. Even when the operation on the operation path 100 is not possible, the first template that operates only a specified distance from the start point P1 or the arrival point P2 in a direction opposite to the specified direction of the vector Xr is applied. The first relay points Q <b> 1 and Q <b> 2 can be automatically and efficiently set without performing and without being affected by the shape of the work 80.
[0088]
The first template moves in a specified direction set in a direction considered to be the easiest to evacuate the work 80, and operates only a specified distance that can be sufficiently evacuated from the work 80 according to the size of the gun unit 68. Although it is a simple method, there is a high possibility that it can be safely evacuated from the work 80. Moreover, since the safety is verified in step S6 and the like, there is no possibility of interference or the like when the articulated robot 50 is actually operated.
[0089]
Further, according to the present embodiment, the first relay points Q1 and Q2 or the second relay points R1 and R2 set on the refuge route are not reachable or interfere with the articulated robot 50. At one time, the prescribed distance between the first and second templates is corrected and the position of the first relay point Q1, Q2 or the second relay point R1, R2 is reset, so that a suitable retreat position can be set. .
[0090]
Further, in the second template, the specified direction is the direction toward the origin O in the coordinate calculation of the articulated robot 50, so that the possibility of interference with the obstacle 82 is low.
[0091]
Further, according to the present embodiment, the first template and the second template are combined and applied, and first the first template is evacuated from the work 80, and then the second template is used for other obstacles 82 and the like. , And safety verification is performed thereafter, so that a route for evacuating and moving can be automatically and efficiently set without performing complicated calculations.
[0092]
The motion path setting method and the setting device of the articulated robot according to the present invention are not limited to the above-described embodiment, but may adopt various configurations without departing from the gist of the present invention.
[0093]
【The invention's effect】
As described above, according to the articulated robot operation path setting method and the setting apparatus according to the present invention, it is possible to automatically and efficiently perform complicated calculations that are not affected by the shapes of works and obstacles. The effect that the motion path of the articulated robot can be set is achieved.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an offline teaching device and a robot device used in the present embodiment.
FIG. 2 is a block diagram illustrating a configuration of an offline teaching device.
FIG. 3 is an explanatory diagram illustrating a configuration of an articulated robot.
FIG. 4 is an explanatory view showing an X-type welding gun.
FIG. 5 is an explanatory diagram showing an operation route from a start point to a destination point.
FIG. 6 is a flowchart (part 1) illustrating a motion path setting method of the articulated robot according to the present embodiment.
FIG. 7 is a flowchart (part 2) illustrating a method of setting an operation path of the articulated robot according to the present embodiment.
FIG. 8 is a flowchart (part 3) illustrating a motion path setting method of the articulated robot according to the present embodiment.
FIG. 9 is an explanatory diagram showing operations of the first and second templates.
FIG. 10 is an explanatory diagram showing a path table.
[Explanation of symbols]
10 Off-line teaching device 12 Robot device
14: control unit 22: robot control unit
26 ... CPU 29 ... RAM
34 ... Hard disk 35 ... Operation path setting program
38: Data creation circuit 40: Simulation circuit
50: Articulated robot 68: Gun unit
70, 72 ... electrode 80 ... work
100, 102, 104, 110, 112 ... operation path
106: fixed point 120: path table
O: origin P1: starting point
P2: arrival point Q1, Q2: first relay point
R1, R2 ... second relay point Xr, Yr, Zr ... vector

Claims (6)

In an operation path setting method of an articulated robot that moves an end effector from a start point to a destination point,
A first step of assuming a path connecting the starting point and the destination point, and examining whether or not the end effector can be operated on the path;
In the first step, when it is impossible to operate on the route, the end effector is referred to from the starting point or the arrival point based on the attitude of the end effector at the starting point or the arrival point. Setting an evacuation route that operates for a specified distance in a predetermined direction. The method for setting an operation path of an articulated robot according to claim 1,
Wherein in a second step, a third step flops when it is impossible to operate on the route, set the retreat path that operates by defining a distance in the direction of the fixed point on the inter empty the end effector
Operation path setting method of the articulated robot, comprising a. The method for setting an operation path of an articulated robot according to claim 2,
The method according to claim 1, wherein the fixed point is a center point of an original axis of the articulated robot. The method for setting an operation path of an articulated robot according to claim 2 ,
A method for setting an operation path of an articulated robot, wherein an end point of the escape route is defined as a new starting point or an arrival point, and the first step and the third step are executed again. The method for setting an operation path of an articulated robot according to any one of claims 1 to 4,
When the end point is an unreachable point or an interference-producing point for the articulated robot, re-setting the evacuation route with the specified distance corrected, the method comprising the steps of: . In a motion path setting device of an articulated robot that moves an end effector from a starting point to a destination point,
Assuming a path connecting the starting point and the destination point, a path investigation unit that investigates whether it is possible to operate the end effector on the path,
When the route investigating unit determines that it is impossible to operate on the route, the end effector is moved from the start point or the arrival point to the end effector at the start point or the arrival point. A path setting unit for setting an evacuation path that moves by a specified distance in a predetermined direction based on the motion path.

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