JPH05134732A - Method for generating interference evasion route - Google Patents

Abstract

PURPOSE:To automatically generate an interference evasion route in short time in the operation program of a robot. CONSTITUTION:When the robot interferes with another object between the initial and last positions of the robot, a temporary evasion point is obtained between the immediately preceding position and the immediately succeeding position of an interference area (S12). When the temporary evasion point interferes with the initial position (S14), it is discriminated whether the immediately preceding position interferes with the temporary evasion point or not (S15), the immediately preceding position is regarded as the initial position when interference exist, the temporary evasion point is re-obtained since the temporary evasion point is regarded as the last position and a case without interference is retrieved (S19). The route connecting the initial position with the temporary evasion point is established and, then, the route connecting the temporary evasion point with the last position is established in a same way (S16, S17 and S21). Thus, the interference evasion route is generated as the route connecting the initial position, the evasion point and the last position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interference avoidance route generation method for generating a motion path of a robot so that the robot does not interfere with other objects during work, and more particularly, to perform automatic generation of the interference avoidance route in a short time. The present invention relates to a method for generating an interference avoiding path that can perform

[0002]

2. Description of the Related Art In recent years, robots have been used in various industrial fields, and accordingly, robots that are easier to use have been demanded. By the way, when creating a robot motion program in an offline system,
When the robot interferes with other objects, the operator is notified in advance of the interference. In that case,
The operator grasps the situation of the interference on the display and designates the route for avoiding the interference, whereby the operation program of the robot is modified and the operation route avoiding the interference is created. As described above, if interference occurs during the creation of the robot operation program, the operator must make corrections.

On the other hand, when interference occurs, severe interference with an object is rare, and usually, a part of a robot often interferes slightly. In such a case, it is desired that the operation program of the interference avoidance route is automatically generated in a short time regardless of the correction work of the operator. Therefore, a method of automatically generating an interference avoidance path such as a configuration method or an energy method has been proposed.

The configuration method is a method in which a normal three-dimensional space is once projected onto a configuration space and a path connecting the initial posture to the final posture in the configuration space is avoided while avoiding the interference region. Further, the energy method is a method of obtaining an interference avoidance route by assuming a potential that becomes higher for each object as it approaches the object and taking a route in which the potential value becomes lower.

[0005]

However, in the configuration method, since the configuration space is generally treated as a mesh, the calculation speed is slow and the calculation takes a very long time. Further, even in the energy method, it takes a lot of time to find a solution. For this reason, even when a part of the robot slightly interferes with each other, it takes a long time to use the method for automatically generating the interference avoidance route, and the operator has to resort to the correction work.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an interference avoidance route generation method capable of automatically generating an interference avoidance route in a short time.

[0007]

In order to solve the above-mentioned problems, the present invention provides an interference avoidance route generation method for generating an operation route of a robot so that the robot does not interfere with other objects during work. When the robot interferes with another object between the position and the final position, a temporary avoidance point is obtained between a position immediately before and immediately after the interference region where the interference occurs, and the initial position and the temporary avoidance point are obtained. When there is the interference between the previous position and the temporary avoidance point, it is determined whether there is the interference between the previous position and the temporary avoidance point. At some time, the temporary position is re-obtained by using the previous position as the initial position and the temporary avoidance point as the final position, and the temporary avoidance point is re-determined between the initial position and the temporary avoidance point or between the previous position and the temporary avoidance point. There is no interference with the avoidance point. At this time, it is determined whether or not there is the interference between the temporary avoidance point and the final position, and when there is the interference between the temporary avoidance point and the final position, the temporary avoidance point It is determined whether or not there is the interference between the position immediately after and the position immediately after, and when there is the interference between the temporary avoidance point and the position immediately after, the temporary avoidance point is set as the initial position. When the position is the final position, the temporary avoidance point is recalculated, and when there is no interference between the temporary avoidance point and the final position or between the temporary avoidance point and the immediately following position, the temporary avoidance point is set. An interference avoidance route generation method is provided, wherein an avoidance point is set as an avoidance point, and a route connecting the initial position, the avoidance point, and the final position is set as an interference avoidance route of the robot.

[0008]

When the robot interferes with another object between the initial position and the final position of the robot, a temporary avoidance point is obtained between the position immediately before and the position immediately after the interference region where the interference occurs. When there is interference between the temporary avoidance point and the initial position, it is determined whether or not there is interference between the immediately preceding position and the temporary avoidance point. When there is interference between the immediately preceding position and the temporary avoidance point, the immediately preceding position is regarded as the initial position, the temporary avoidance point is regarded as the final position, the temporary avoidance point is recalculated, and the case where there is no interference is searched. To do.

On the other hand, when there is no interference between the initial position and the temporary avoidance point or between the immediately preceding position and the temporary avoidance point, the route connecting the initial position and the temporary avoidance point, or the initial position and the previous avoidance point. A path connecting the position and the temporary avoidance point is established as an interference avoidance path, and then it is determined whether or not there is interference between the temporary avoidance point and the final position. When there is interference between the temporary avoidance point and the final position, it is determined whether or not there is interference between the temporary avoidance point and the position immediately after. When there is interference between the temporary avoidance point and the position immediately after, the temporary avoidance point is regarded as the initial position, and the position immediately after is regarded as the final position, and the temporary avoidance point is recalculated to search for a case where there is no interference. To do.

When there is no interference between the temporary avoidance point and the final position or between the temporary avoidance point and the position immediately after, the route connecting the temporary avoidance point and the final position, or the temporary avoidance point and the immediate position. Establish a route connecting the position and the final position as an interference avoidance route,
The temporary avoidance point is set as the avoidance point. This allows
The interference avoidance route is generated as a route connecting the initial position, the avoidance point, and the final position. When there are a plurality of interference areas on the movement path of the robot, the avoidance point setting procedure is sequentially performed from the first interference area.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 3 is a diagram showing an overall configuration for implementing the interference avoidance route generation method of the present invention. In the figure, an offline programming device 10 is mainly composed of a microprocessor, and creates an operation program of a robot offline. A workstation, for example, is used as the off-line programming device 10. The operation program created by the off-line programming device 10 is sent to the robot controller 20. The robot controller 20 drives the servo motor of the robot 30 to operate the robot 30 based on its operation program.

In the off-line programming device 10, the motion of the robot is simulated based on the motion program created in advance. At that time, if the robot interferes with other objects or makes a near miss, a route for avoiding the interference or near miss is automatically generated.
The automatic generation of the interference avoidance route executed by the offline programming device 10 will be described below.

FIG. 4 is a diagram showing a case where there is an interference area on the movement path of the robot. The robot interferes with the object 1 while moving from the initial position (initial posture) A to the final position (final posture) B, and an interference area 11 is formed. A method of generating the interference avoidance path in this case will be described. First, the interference area 1
A temporary avoidance point m is obtained between the immediately preceding position p and the immediately following position q of 1. This temporary avoidance point m is the immediately preceding position p and the immediately following position q.
Is obtained on or near the bisector of. Next, it is determined whether or not there is interference between the initial position A and the temporary avoidance point m, and if there is no interference, the path 51 connecting the initial position A and the temporary avoidance point m is once established. If there is interference between the initial position A and the temporary avoidance point m, it is further determined whether or not there is interference between the immediately preceding position p and the temporary avoidance point m. A path connecting A, the immediately preceding position p, and the temporary avoidance point m is once established. On the other hand, a case where there is also interference between the immediately preceding position p and the temporary avoidance point m will be described later.

Similarly, it is determined whether or not there is interference between the temporary avoidance point m and the final position B, and if there is no interference, a path 52 connecting the temporary avoidance point m and the final position B is established. Then, the temporary avoidance point m is set as the avoidance point M. As a result, the routes 51 and 52 of the initial position A, the avoidance point M, and the final position B are established, and the interference avoidance route 50 is generated. When there is interference between the temporary avoidance point m and the final position B, the route is obtained in the same manner as when there is interference between the initial position A and the temporary avoidance point m. Next, a case where there is interference between the immediately preceding position p and the temporary avoidance point m will be described.

FIG. 5 is a diagram showing a case where there is interference between the immediately preceding position and the temporary avoidance point. (A) shows step 1 and (b) shows.
Indicates step 2 respectively. As shown in FIG. 5A, when there is the interference area 110 between the immediately preceding position p and the temporary avoidance point m, the immediately preceding position p is regarded as the initial position A1 and the temporary avoidance point m is determined as the final position B1. And the temporary avoidance point m is recalculated. That is, the temporary avoidance point m1 of this time is as shown in FIG.
As shown in (b), the paths 510 and 520 are obtained between the immediately preceding position p1 and the immediately following position q1 of the interference region 110, and the paths 510 and 520 are established by the same procedure as in the case of FIG. 4, whereby the interference avoidance path 500 is established. To be done.

FIG. 6 is a diagram showing a case where there are a plurality of interference regions on the movement path of the robot. Interference areas 12, 13 and 14 exist on the operation path from the initial position A to the final position B. In this way, the plurality of interference regions 12, 13, 14
In the case where there is an interference avoiding path, the interference avoiding path is first generated for the first interference area 12 and then for the interference areas 13 and 14 in this order. In that case, for example, the initial position A with respect to the interference region 13 is, for example, the position q2 immediately after the front interference region 12.
Further, the final position B may be the position q3 immediately after the own interference region 13. By applying the procedure described in FIGS. 4 and 5 to each of the interference regions 12, 13, and 14,
An interference avoidance route from the initial position A to the final position B is generated.

FIG. 2 is a diagram showing a program flow chart for executing the interference avoidance route generation method of the present invention. Here, description will be made on the assumption that a plurality of interference regions exist. The numbers following S in the figure represent step numbers. [S1] It is inspected whether there is interference between the initial position A and the final position B. [S2] It is determined whether there is interference. If there is interference, the process proceeds to step S3, and if not, the program ends as it is. [S3] The number i is set to 1. [S4] The interference avoidance route generation loop shown in FIG. 1 is executed,
An interference avoidance route for the i-th interference area is obtained. That is, the interference avoidance path is generated by sequentially executing the interference areas from the first interference area. [S5] It is determined whether or not the execution of the interference avoidance route generation loop for each interference region is completed. If it is executed, the interference avoidance path has been generated, so the program ends. If not, the process proceeds to step S6. [S6] 1 is added to the number i so that the interference avoidance route generation loop is executed for the next interference region.

FIG. 1 is a flowchart of an interference avoidance route generation loop. This flowchart is executed for the i-th interference area. The numbers following S in the figure represent step numbers. [S11] It is determined whether or not the procedure for establishing a series of interference avoidance routes, that is, the number of times the steps S11 to S17 are repeated is equal to or greater than the designated maximum number. If it is the specified maximum number of times or more, the process proceeds to step S23, and if not, the process proceeds to step S12. [S12] Between the initial position A and the final position B, that is,
A temporary avoidance point m is obtained between the position p immediately before and the position q immediately after the interference region. [S13] It is determined whether or not the temporary avoidance point m has been obtained successfully. If successful, the process proceeds to step S14, and if not, the process proceeds to step S23. [S14] It is determined whether there is interference between the initial position A and the temporary avoidance point m. If there is interference, the process proceeds to step S15, and if there is no interference, step S15 is skipped and the process proceeds to step S16.

[S15] It is determined whether or not there is interference between the immediately preceding position p and the temporary avoidance point m. If there is interference, the process proceeds to step S19, and if there is no interference, the process proceeds to step S16. [S16] It is determined whether or not there is interference between the final position B and the temporary avoidance point m. If there is interference, the process proceeds to step S17, and if there is no interference, step S17 is skipped and the process proceeds to step S18. [S17] It is determined whether or not there is interference between the position q immediately after and the temporary avoidance point m. If there is interference, go to step S21,
If there is no interference, the process proceeds to step S18. [S18] The temporary avoidance point m is set as the avoidance point M, and the program for the established interference avoidance route is written. [S19] The immediately preceding position p is regarded as the initial position A, the temporary avoidance point m is regarded as the final position B, and steps S11 to S15 are re-executed. [S20] If the re-execution in step S19 is successful, the process proceeds to step S16, and if not, the process proceeds to step S23. [S21] The temporary avoidance point m is regarded as the initial position A, the position q immediately after is regarded as the final position B, and steps S11 to S17 are re-executed. [S22] If the re-execution in step S21 is successful, the process proceeds to step S18, and if not, the process proceeds to step S23. [S23] This is a case where the number of repetitions of the procedure for establishing a series of interference avoidance routes is equal to or more than the specified maximum number, and a warning is issued to make it difficult for the operator to generate an interference avoidance route. Notify that it will take time. In this case, the operator specifies the interference avoidance route and corrects the robot movement route. As a result, it is possible to quickly generate the interference avoidance route without wasting time.

Next, the automatic generation of the above-mentioned interference avoidance route will be described using a robot motion simulation. FIG. 7 is a diagram showing a case where the robot simulates a case where the robot interferes with another object, and (a) shows an initial posture,
(B) shows the case of interference, and (c) shows the final posture. The robot 30 is changed from the initial posture shown in FIG.
While moving to the final posture of (c), the arm 31 moves to the pillar 3
5 (FIG. 7B). An operation program example at this time is shown below.

#BPF 100% T-30 W0
U0 C0 B0 A0BE #B P F100% T30 W0 U0 C0 B
0 A0 BE #B PE Here, the robot 30 is a 6-axis robot, and the θ axis thereof shows −30 ° in the initial posture and 30 ° in the final posture, and interferes with the pillar 35 between them.

FIG. 8 is a diagram showing a case in which a case where an interference avoidance route is automatically generated is simulated. (A) shows an initial posture, (b) shows a case where interference is avoided, and (c) shows a final state. Each posture is shown. The robot 30 avoids the interference with the pillar 35 and moves from the initial posture to the final posture. At this time, an operation program example automatically generated by the interference avoidance route generation method of the present invention is shown below.

#BPF 100% T-30 W0
U0 C0 B0 A0BE #BPF 100% T2.29 W-10.31
U16.04 C0.57 B-16.04 A-0.
57 BE #B P F 100% T30 W0 U0 C0 B
0 A0 BE #B PE That is, the avoidance point M at which the robot 30 avoids the interference with the pillar 35 is 2.29 ° in the θ axis, 10.31 ° in the W axis, 16.04 ° in the U axis, and 0. 57 °, β-axis-16.04 °,
The α axis is set as −0.57 °, and the robot 30 does not interfere with the pillar 35 by passing through the avoidance point M.
It is possible to move from the initial posture to the final posture.

In the above description, the present invention is applied to the interference between the robot and another object, but it can be similarly applied to the near miss between the robot and the other object. .. In that case, the case where the distance between the robot and another object approaches a certain distance or more may be considered as a near miss.

[0025]

As described above, according to the present invention, when the robot interferes with another object, an avoidance point is provided and an interference avoidance route is automatically generated. Therefore, even if interference occurs, it is possible to automatically generate the interference avoidance route in a short time regardless of the work of the operator. that time,
When it is difficult to generate the interference avoidance route or when it takes a considerable time, the operator is warned, so that the interference avoidance route can be promptly generated without wasting time.

[Brief description of drawings]

FIG. 1 is a flowchart of an interference avoidance route generation loop.

FIG. 2 is a diagram showing a program flow chart for executing the interference avoidance route generation method of the present invention.

FIG. 3 is a diagram showing an overall configuration for implementing an interference avoidance route generation method of the present invention.

FIG. 4 is a diagram showing a case where there is an interference area on the movement path of the robot.

5A and 5B are diagrams showing a case where there is an interference between the immediately preceding position and a temporary avoidance point, in which FIG. 5A shows step 1 and FIG. 5B shows step 2.

FIG. 6 is a diagram showing a case where there are a plurality of interference regions on the movement path of the robot.

FIG. 7 is a diagram showing a case where a robot simulates a case where the robot interferes with another object, and FIG.
(B) shows the case of interference, and (c) shows the final posture.

FIG. 8 is a diagram showing a case where a case where an interference avoidance route is automatically generated is simulated, and (a) shows an initial posture,
(B) shows the case where interference is avoided, and (c) shows the final posture.

[Explanation of symbols]

 10 Offline programming device 11, 12, 13, 14, 110 Interference area 30 Robot 50,500 Interference avoidance route A, A1 Robot initial position B, B1 Robot final position p1, p2, p3, p4 Last position q1, q2 Immediately after q3, q4

Claims (6)

[Claims] 1. A method of generating an interference avoidance path for generating a motion path of a robot so that the robot does not interfere with another object during work, wherein the robot is in contact with another object between an initial position and a final position of the robot. When interfering, the temporary avoidance point is obtained between the position immediately before and the position immediately after the interference region where the interference occurs, and when there is the interference between the initial position and the temporary avoidance point, the immediately preceding position and the When it is determined whether there is the interference with the temporary avoidance point, and when there is the interference between the previous position and the temporary avoidance point, the previous position is set as the initial position and the temporary avoidance is performed. Redetermining the temporary avoidance point with a point as the final position, when there is no interference between the initial position and the temporary avoidance point or between the immediately preceding position and the temporary avoidance point, the temporary avoidance point Between the avoidance point and the final position When there is interference between the temporary avoidance point and the final position, it is determined whether or not there is interference between the temporary avoidance point and the immediately-following position. Determine, when there is the interference between the temporary avoidance point and the immediately after position, re-obtaining the temporary avoidance point with the temporary avoidance point as the initial position and the immediately following position as the final position, When there is no interference between the temporary avoidance point and the final position or between the temporary avoidance point and the immediately following position, the temporary avoidance point is set as an avoidance point, and the initial position and the avoidance point are set. And a method of generating an interference avoiding path, characterized in that a path connecting the final positions is used as an interference avoiding path of a robot. 2. The interference avoidance route generation method according to claim 1, wherein when there are a plurality of interference regions, the avoidance point is set sequentially from the first interference region. 3. The interference avoidance according to claim 1, wherein the temporary avoidance point is obtained on a bisecting line between the position immediately before the interference and the position immediately after the interference or in the vicinity of the bisecting line. Route generation method. 4. The interference avoidance route generation method according to claim 1, wherein a maximum number of times of re-obtaining the temporary avoidance points is set in advance. 5. The interference avoidance route generation method according to claim 4, wherein when the temporary avoidance point recalculation exceeds the maximum number of times, the operator is warned. 6. The method according to claim 1, wherein the method is also applied to a near miss between the robot and the other object.
The interference avoidance route generation method described.