JPH08305429A - Method for restarting robot after emergency stopping - Google Patents

Abstract

PURPOSE: To make the moving path of a robot after restart close to the path when there is no emergency stopping by preventing interference between the robot and the other object when restarting the operation of the robot after sudden stopping. CONSTITUTION: A position S0, where an emergency stop command is inputted, is stored and when restarting the operation, the robot is moved from a real stop position Se to the emergency stop command position S0 at low speed. An intersection S3 of a rough tangent at the emergency stop command position S0 of a robot moving path 1 and a second route to form a corner part is obtained. The start and end points of a first route to form the corner part of a teaching program are replaced with positions S0 and S3, the start point of the second route is defined as S3, and the robot operation is restarted from the emergency stop command position S0. The robot track after restart is made almost equal to the path when there is no emergency stopping.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for resuming operation after a robot operation is suddenly stopped due to an emergency stop or the like.

[0002]

2. Description of the Related Art In an industrial robot, when a sudden stop command signal such as an emergency stop is input while a path interpolation operation is being executed by a teaching program, the motors that drive the robot axes are braked and the motor excitation is lost. Be done. Also, the interpolation process is stopped, and the robot mechanism unit decelerates and stops.
When the robot operation speed is high, the robot cannot stop suddenly due to the moment of inertia and other influences,
The stop position of the robot stops at a position deviated from the original movement trajectory. For example, the operating speed of the robot is 2000 mm /
If the vehicle suddenly stops in the state of sec, the moving distance until the stop is input and the stopping is required to be about 100 mm, and there is a possibility that the moving path deviates by this amount.

In particular, at the corners of the joints of straight lines and arcs for which no positioning is instructed, the movement direction changes from moment to moment, so the amount of deviation from this movement path becomes large. That is,
In the case of no positioning command, it reaches the vicinity of the end point of the block (target position of the block) and starts deceleration, and at the same time, the operation to move to the end point of the next block is started. The deceleration to the end of the block and the acceleration to the end of the next block are performed at the same time, and the joint of the straight line or the arc is moved along the smooth curve, and the operation that suppresses the speed decrease is performed. Therefore, when a sudden stop is made at the corner near the joint, the robot stop position is largely deviated from the original movement route because the movement direction is constantly changing.

Further, in the case of a command without positioning, since it is moving in a corner portion of a joint of a straight line and a circular arc while drawing a locus different from the moving path of the teaching program command, it moves at a low speed. Even if there is no movement after the sudden stop command (stop distance “0”), the robot stop position is different from the teaching program path. Conventionally, the resuming operation after the sudden stop is to move from the robot stop position to the next teaching point (end point of the next block). From this fact, if the stop position deviates from the movement path of the teaching program, the robot moves from this robot stop position to the next teaching point (end point of the block) with a different trajectory from the one instructed by the teaching program. Will be done.

[0005]

Generally, the movement path of a robot is taught so that the robot's hands and arms do not interfere with other objects. Therefore, if the actual movement trajectory of the robot deviates from the teaching program path, the robot hand or arm may interfere with other objects. When teaching with a command without positioning, the tool center point (hereinafter TCP
Is a joint of the corner portion, and even if the robot moves smoothly from the first path forming the corner to the second path without passing through the teaching point of the seam, another object and the robot hand or arm are It is used when there is no interference, and it is confirmed by test operation that interference does not occur even when operated by a command without positioning. Therefore, when the robot is driven according to the teaching program, the actual robot movement locus is a locus that does not interfere with other objects. However, if the robot movement trajectory deviates from the actual movement trajectory driven according to the teaching program, it may interfere with other objects.

The robot is suddenly stopped by a sudden stop command, and its stop position is deviated from the movement locus operated according to the teaching program. When the operation is restarted from this stop position, the next block is moved from this sudden stop position. Until the end point of, the robot will move on a trajectory different from the trajectory for which safety is confirmed. Therefore, the robot hand or arm may interfere with other objects. or,
As a special teaching method, the teaching point of the joint of the corner portion is set at a position where the robot interferes with other objects, and the robot is operated by a command without positioning to set the teaching point of the corner portion to T.
In some cases, the final teaching program for the robot may be made by checking that the robot does not interfere with other objects by a test operation or the like so that the PC does not pass through.

From the above, as a method of restarting the operation after the robot suddenly stops, it is desirable to move the robot in a route close to the locus of the robot actually moving according to the teaching program so as not to interfere with other objects. . Therefore, an object of the present invention is to provide a restarting method after a sudden stop of a robot that prevents interference between the robot and other objects when the operation is restarted after the sudden stop of the robot. Another object of the present invention is to provide a resuming method in which the robot movement locus after resuming moves along a locus as close as possible to the locus of movement of the robot when there is no sudden stop.

[0008]

According to the present invention, a sudden stop command position at the time of input of a sudden stop command is stored, and a low speed set at the stored sudden stop command position by a robot operation restart command. Move with. When the teaching path is a corner portion of a straight line / straight seam or a straight line / arc joint, and the sudden stop command position is not on the teaching route, a rough tangent line and a corner portion at the sudden stop command position on the robot movement locus. To find the intersection of the taught first path and the second path in the following second path. The intersection is defined as an intermediate point, and instead of the start point and the end point of the first path, a path where the sudden stop command position is set as the start point and the intermediate point is defined as the end point is set, and the intermediate point is set instead of the start point of the second path. Starting from, the robot operation is restarted from the sudden stop command position.

As a method for obtaining the intermediate point of the intersections of the tangent line and the second path, on the plane including the taught first and second paths, the sudden stop command position is parallel to the linear teaching path. The intersection between the line passing through and the other teaching route is obtained, and the intersection and the sudden stop command position are defined as one side, and the sudden stop command position, the intersection, and the taught first and second directions are set.
The vertices on the second route when the parallelogram with the joint of the route as the vertex is set as the vertex are obtained. Then, the position on the route is defined as the intermediate point at a distance from the starting point of the second route that is equal to the distance obtained by doubling the distance between the starting point of the second route and the apex. In addition, by setting the intermediate point as a point on the second path in which the correction amount based on the angle of the seam is added to the intersection point of the second path and the tangent line, the robot path can follow the program path. Let's be close.

As another method, a position on the path of the teaching program near the sudden stop command position is obtained, the position is moved from the sudden stop command position to the position, and the starting point of the route of the teaching program at which the position is located. Is replaced with the position and the robot operation is restarted from the intersection. In particular, after obtaining the intersection of the line passing through the sudden stop command position in parallel with the straight teaching path and the other teaching path, and moving at the speed set to the sudden stop command position,
The robot is moved to the intersection, the start point of the route of the teaching program having the intersection is replaced with the intersection, and the robot operation is restarted from the intersection. As yet another method, after moving at the speed set to the stored sudden stop command position, further moved to the seam at a set speed from the sudden stop command position,
By restarting the robot operation from the position and moving the robot according to the teaching route, interference with other objects is prevented.

[0011]

FIG. 3 is an explanatory diagram for explaining the operation of the resuming method of the present invention. In FIG. 3, the path of the teaching program is the first straight path from the teaching point P1 to the teaching point P2 and the teaching point P.
This is an example when the robot is driven by a command without positioning in the corner portion formed by the second straight line from 2 to the teaching point P3. In this case, the TCP movement locus of the robot actually becomes the locus indicated by reference numeral 1, but during this movement, when a sudden stop command is input at the position S0, this sudden stop command input position S0 is stored. If the robot moves from the sudden stop position S0 and actually stops at the position Se (see FIG. 3 (a)), at the time of restart, the robot actually stops from the position Se at the sudden stop command position. It is moved at the low speed set to S0 (see FIG. 3 (b)). In this case, since the robot has moved from the sudden stop command position S0 to this actually stopped position Se, the robot hand or arm can normally be moved to the position S0 without interfering with other objects. .

The tangent line of the robot movement locus at this sudden stop command position S0 is obtained, and the intersection S3 between this tangent line and the second path is determined.
Ask for. When the start and end points of the first path are set to the sudden stop command position S0 and the intersection point S3, and the start point of the second path is set to the intersection point S3, the robot operation is restarted from the sudden stop command position S0. Indicates that the robot moves along a route close to the route 1 when the robot moves according to the teaching program (see FIG. 3C). When operating the robot with no positioning command, the teaching program path (point P1,
P2, P3 path) and the actual trajectory that the robot will take when operating with the program (the trajectory of reference numeral 1 in FIG. 3)
Between and are areas where the robot does not normally interfere with other objects. This is because when the robot is operated with no positioning command, the actual robot trajectory changes due to the relationship between the moving speed and the angle of the corners, so that the robot's hand or arm and other objects do not interfere with each other during test operation. Since the teaching program is confirmed by confirming the above, the robot hardly interferes with other objects in the area between the program path and the actual robot movement locus.
In addition, by the above-described method, even when the robot operation is restarted after a sudden stop, the robot moves along a locus similar to the locus of movement according to the teaching program, so that the robot's hand or arm interferes with other objects. There is almost nothing to do.

FIGS. 4, 5, and 6 are explanatory views of an example of a method for obtaining an intersection S3 between the tangent line at the sudden stop command position of the robot movement locus and the second path. 4 is a case where the first and second paths forming the corner portion of the teaching program are straight lines, FIG. 5 is a case where the first path is a straight line and a second path is an arc, and FIG. 6 is a first path. Is an arc and the second path is a straight line. On a plane including the first and second paths, an intersection of a line passing through the sudden stop command position in parallel with the straight teaching path and the other teaching path is obtained. In the case of FIG. 4, the intersection point S1 on the first path and the intersection point S2 on the second path are obtained, and the straight line passing through the intersection points S1 and S2 is set as the direction of the tangent line at the sudden stop command position S0 on the robot movement locus. S1, S
When a straight line passing through 2 is translated to a straight line passing through the sudden stop command position S0, the intersection S3 between this straight line and the second path is obtained. In the quadrilateral consisting of the points S0, S1, P2, and S2, the line segment S0 S1 and the line segment P2 S2 (second path P2 P3) are parallel, and the line segment S0 S2 and the line segment S1 P2 (first path P1 P
Since 2) is parallel, it is a parallelogram. Therefore, the intersection point S3 is located at a position on the second route that is a distance obtained by doubling the distance between the point P2 and the point P2 (line segment P2 S2 = line segment S2 S3). Therefore, the position on the second route can be obtained at the distance from the point P2 which is equal to the distance obtained by doubling the distance from the point P2 to the intersection S2, and this position can be obtained as the position of the point S3.

When the first path shown in FIG. 5 is a straight line and the second path is a circular arc to form a corner, a straight line parallel to the first path and passing through the sudden stop command position S0 is used. The intersection S2 with the second path is obtained, and the vertex S1 on the first path is obtained from the parallelogram having the points S0, S2, and P2 as the vertices. As described above, this vertex S1 must be obtained. However, the distance on the second path from the point P2 is equal to the length on the second path from the point P2 to the intersection point S2, which is equal to twice the length on the second path. The intersection S3 of the tangent line of the robot movement locus and the second path can be obtained.

When the first path shown in FIG. 6 is a circular arc and the second path is a straight line to form a corner portion, a straight line parallel to the straight line of the second path and passing through the sudden stop command position S0 and the first line The intersection point S1 with the path is obtained, and the vertex S2 on the second path is obtained from the parallelogram having the points S0, S2, and P2 as the vertices, but the line segment S0 S1 = the line segment P2 S2 and the line Minute P2S3
Is twice the line segment P2 S2, so the sudden stop command position S0
The intersection point S3 with the tangent of the robot trajectory at is the point P2.
From the line segment S0 S1 is obtained as the position on the second route of the distance doubled.

The tangent line according to the method described above is an approximate guess because it is not clear what the locus of movement of the robot actually is. The intersection S3 between this tangent line and the second route is also the end point of the first route after restarting,
It is experimentally determined that the same trajectory as the approximate robot movement trajectory can be obtained by setting the starting point of the second path. Therefore, the position S3 may be corrected by the angle of the corner or the like to S3 ', and the robot movement locus after the robot operation is restarted may be corrected so as to be closer to the robot movement locus when there is no sudden stop.

The above-described method for restarting the robot operation is a method for restarting the operation of the robot from the sudden stop command position S0. However, even if the robot hand or arm passes through the teaching point P2 forming the corner portion, the robot hand or arm may be another object. If it does not interfere with, the position of the teaching program route near the sudden stop command position S0 is obtained and the operation is restarted from that position, or the starting point P2 of the second path is set as the starting point for restarting the robot operation. it can. In this case, the position Se at which the robot actually stops is a region surrounded by the first and second paths forming the corner and the robot movement locus (reference numeral 1 in FIG. 3) when operating on this teaching program path. If it is within the range, from the robot stop position Se to the sudden stop command position S
Even if the robot TCP is moved to the position or position P2 of the teaching program path near 0, the robot hand and arm rarely interfere with other objects, but it is also possible that the stop position Se goes out of this area. In this case, the TCP of the robot is moved from the robot stop position Se to the position P2 of the teaching program path near the sudden stop command position S0 or the position P2.
If you move, the robot may interfere with other objects. Therefore, first, from the stop position Se to the sudden stop command position S
When the position is returned to 0, and the position is next to the sudden stop command position S0, the position is moved to the position S1, S2 or P2, and the robot operation is restarted from the position S1, S2 or P2.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of a main part of a robot control system for carrying out a method for restarting a robot after a sudden stop according to the present invention. The robot controller 10 includes a processor 11 that executes robot control, and the processor 11 includes a ROM 1
2, RAM 13, non-volatile memory (RAM) 14, teaching operation panel 15, and robot axis control unit 16 are connected by a bus 18, and the robot axis control unit 16 servos each axis of the robot mechanism unit 20 via a servo circuit 17. It is designed to drive a motor. In FIG. 1, the servo circuit 17 provided for each axis is represented by one block.

The ROM 12 stores basic control software executed by the processor 11, and the non-volatile memory 14
Stores a teaching program taught by the teaching operation panel 15 or the like. The RAM 13 is used for temporary storage of data and the like. The configuration of the robot control system is the same as the conventional one, and the details are omitted. Figure 2
7 is a flowchart of an example of an operation process of the restart method of the present invention, which is executed by the processor 11 of the robot controller 10 when a restart command is input after a sudden stop. When a sudden stop command is input for some reason during robot operation, the processor 11 determines the current position of each axis based on a position feedback signal from a position detector attached to a servo motor that drives each axis of the robot. The position of each axis of the robot at the time of inputting the sudden stop command is read from the stored current value register and stored as the sudden stop command position S0. Then, the servo motor is braked to stop the movement of each axis and the interpolation process is stopped. As a result, the robot mechanism unit 2
0 decelerates and stops.

After that, when a robot operation restart command is input from the teaching operation panel 15, the processor 11 starts the processing shown in FIG. First, the robot mechanism unit 20 is moved at the low speed set at the stored sudden stop command position S0 (step T1). Next, it is judged whether or not the program command is a path operation, that is, whether or not the block of the program being executed at the time of sudden stop or the next block is each axis movement (step T2). For example, the process proceeds to step T19, and the block whose start point is the sudden stop command position S0 and whose end point is the next block is used as a substitute for the block next to the program command, and the operation is restarted from the sudden stop command position S0.

If it is a path operation, it is judged whether the sudden stop command position is a position on the path of the block of the teaching program in which the interpolation processing was executed at the time of the sudden stop (step T).
3). When the sudden stop command position is not at a corner or when a positioning command (command that is not positioning), there is only one block that executes interpolation processing,
When the command is a command without positioning, the block of the first path forming the corner part is subjected to interpolation processing accompanied by deceleration processing, and accompanied by acceleration processing of the block of the second path following the first path. Although the interpolation process is being performed, the block at the time of the sudden stop command in this case is performing the deceleration process.
The block of the route of. And in this case, the first
Since the block deceleration processing of the route of No. 2 and the acceleration processing of the block of the second route are being performed, the sudden stop command position S0
Is not on the first path (and of course not on the second path).

When it is determined in step T3 that the sudden stop command position S0 is on the path of the block at the time of the sudden stop command, the process proceeds to step T13, and the start point of the block at the time of this sudden stop command is set as the sudden stop command position S0. , Restart the robot operation from the position S0. That is, if the path that is the command of the block at the time of the sudden stop command is the linear command, the interpolation processing of the linear movement with the start point as the sudden stop command position S0 and the end point as the end point of the block (point P2 in FIG. 3) is performed. After that, the teaching program is executed as instructed thereafter. If the command of the block at the time of the sudden stop command is a circular arc, the interpolation processing of the circular arc having the same radius as the program command having the sudden stop command position S0 as the start point and the end point P2 of the block as the end point is executed, and thereafter. , Teaching program Execute as instructed.

When the sudden stop command is issued at the corner of the non-positioning command and the sudden stop command position S0 is not on the teaching program command path, the block at the sudden stop command (hereinafter this block is referred to as the first block, That route is referred to as a first route) is a straight line (step T4), and if it is a straight line, it is parallel to the straight line of the first route as shown in FIGS. Find a straight line L1 passing through S0,
An intersection S2 between the straight line L1 and the path (second path) of the next block (this block is called a second block and that path is called a second path) is obtained (step T5,
T6). Second path (Teach point P2 P in FIGS. 4 and 5)
The position S3 where the distance on the second route from the starting point (end point of the first route) P2 of the route between 3) is equal to the length obtained by doubling the length between the starting point P2 and this intersection point S2 is described above. As described above, since it means the intersection with the approximate tangent line at the sudden stop command position S0 on the robot movement locus, as shown in FIGS. 4 and 5, the approximate tangent line and the intersection S3 of the second route from the position of the above intersection S2. Is calculated (step T7).

The start point of the first block is the sudden stop command position S0 and the end point is the intersection point S3, and the speed with respect to the first block is a linear command which is a command of the first block (a linear command or an arc command). Block B1 by command
(A block that changes only the start and end points of the first block)
Is made (step T8). Next, it is determined whether or not the next block (second block) is a straight line command (step T9). If it is a straight line command, the start point is the intersection point S3 and the end point is the end point P3 of the second block. Then, a block B2 (a block B2 in which only the starting point of the second block is changed to S3) having a speed command equal to the speed command for the second block is generated by the linear command (step T10). If it is determined in step T9 that the second block is the circular arc command, the start point is the intersection point S3 and the end point is the end point P of the second block.
3, the arc command which is the command of the second block, and the block B2 of the speed command which is equal to the speed command for the second block
(Block B2 in which only the starting point of the second block is changed to S3
(Step T11) The robot operation is restarted from the start point of the block B1 of the blocks B1 and B2 thus created, that is, the sudden stop command position S0, and the processing of the blocks B1 and B2 is performed instead of the second block. Then, the processing according to the teaching program is executed (step T
12). In step T4, when the command of the first block is the circular arc command, it is determined whether the command of the next block (second block) is the circular arc command (step T14). Therefore, the process proceeds to step T19, where the start point is the abrupt stop command position S0 and the end point is the end point of the second block, and the block is the same arc command as the arc command of the second block and the same speed command. (A block in which the start point of the second block is only changed to the sudden stop command position S0) is created, and the robot operation is restarted from the start point (abrupt stop command position S0) of the block instead of the second block.

If it is determined in step T14 that the second block is a linear command, as shown in FIG.
A straight line L2 that is parallel to the straight line of the path of (1) and passes through the sudden stop command position S0 is found, and an intersection S1 of the straight line L2 and the path of the first block is found (steps T15 and T16). The position S3 on the second route from the starting point P2 of the route of the second block corresponding to the distance obtained by doubling the distance from the intersection S1 to the sudden stop command position S0 is obtained (step T17), and the sudden stop command position S0 is obtained. Is a start point and the intersection point S3 is an end point, and a block B1 is a circular block command which is a command (a straight line command or a circular arc command) for the first block and a speed command for the first block.
(A block that changes only the start and end points of the first block)
Is made (step T18). Then, the process proceeds to step T10 and the above-described processing is performed to start the robot operation from the sudden stop command position S0.

In the above embodiment, the intersection point S3 between the tangent line and the second path is set as the end point of the newly created block B1 and the start point of the block B2, but the position of this intersection point S3 depends on the corner angle and the robot moving speed. May be corrected. The correction amount is determined so that the robot movement trajectory after restarting approaches the robot trajectory when the sudden stop does not occur. Generally, when the corner angle is small, the correction amount is large, and the corner angle is 9
The correction amount is about 0 at about 0 degree, and becomes negative when the corner angle is larger than 90 degrees. When adding the correction amount, the correction amount may be added to the position S3 obtained in steps T7 and T17 of the flowchart of FIG.

Further, in the above embodiment, the robot trajectory after resuming the robot operation is approximated to the robot movement trajectory before the sudden stop to prevent the interference of the robot with other objects. P2 has no obstacles (usually
The teaching position is set at a position where the robot and other objects do not interfere with each other.In a special case, the teaching position is set to the position where the robot and other objects do not interfere with each other so that the robot and other objects do not interfere with each other. In some cases, the operation may be restarted from a point on the teaching program program path that is close to the sudden stop command position S0.

The position of the teaching point P2 forming the corner portion is a position where the robot and other objects do not interfere with each other, and the operation is performed by the command without positioning means that the command without positioning means that the corner portion is moved. In the first path and the second path that are configured, the first path is decelerated, the second path is accelerated, and the deceleration and the acceleration are performed at the same time, so that the robot smoothly moves in the corner portion. The actual movement trajectory of the robot changes depending on the movement speed and the like. Therefore, the teaching program is finally decided by confirming that the robot and other objects do not interfere with each other by a test operation or the like. From this, it can be considered that the area between the teaching program path and the actual robot movement locus does not interfere with the robot and other objects.

When the robot moves and stops from the sudden stop command position S0, the position Se is not always in the above area. If the robot is moved directly from the stop position Se onto the teaching program path, the robot and other objects may interfere with each other. However, since the robot actually moves from the sudden stop command position S0 to the actually stopped position Se, even if the robot is moved from the actual stop position Se to the sudden stop command position S0, the robot and other objects may move. There is no interference. Therefore, from the stop position Se to the sudden stop command position S0
It is also possible to move the robot at a low speed set to 1, then move it to a position near the sudden stop command position S0 at a low speed set on the teaching program path, and restart the operation from this position. In this case, for example, the sudden stop command position S0
From the above, the teaching point may be moved to the teaching point P2 forming the corner portion, and the teaching program may be executed from this position (execution from the second block). In the processing shown in FIG. 1, steps T4 to T12 and T14 to When it is determined in step T3 that the sudden stop command position S0 is not on the teaching program path, the processing of T11 is not necessary, and the robot is restarted from the teaching point P2 forming the corner at a low speed. Good.

In order to restart the operation from the position on the teaching program path near the sudden stop command position S0,
The simplest method is to make the first and second corners.
It is also possible to find an intersection of a straight line passing through the sudden stop command position S0 and the other route, which is parallel to the inner straight line of the route, and restart the robot operation from the intersection. For example, in FIG.
As described above, the intersection point S1 or the intersection point S2 is obtained, the intersection point S2 is obtained in the example of FIG. 5, the intersection point S1 is obtained in the example of FIG. 6, and the obtained intersection point is the point S on the second route.
If 2, then the second teaching program that forms the corner
It suffices to replace the starting point of the block with the intersection S2 and restart the operation from the intersection S2. The obtained intersection is the point S1 on the first route.
In this case, the starting point of the first block of the teaching program may be replaced with the intersection point S1 and the operation may be restarted from the intersection point S1.
In this case, in the processing of FIG. 1, instead of the processing of steps T7 to T12, the intersection S2 obtained in step T6 is used as the starting point of the second block of the teaching program to restart the operation from the position S2. T17
Instead of the processing from T18 to T18, the intersection point S1 obtained in step T16 may be used as the starting point of the first block of the teaching program and the operation may be restarted from that position.

[0031]

According to the present invention, when the robot operation is restarted after a sudden stop, the robot is operated on a trajectory close to the trajectory when there is no sudden stop, or near the teaching program path. It produces the effect like. (1) It is possible to prevent the hand and arm of the robot from interfering with other objects. (2) The robot work can be restarted from the position where the sudden stop command is input or the position close to the position. (3) Even if the movement distance of the robot after the abrupt stop command is input becomes long, the work can be executed on the almost same route as the route of the teaching program. (4) Recovery work after a sudden stop is easy and the time can be shortened.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a robot control system that implements an embodiment of the present invention.

FIG. 2 is a flow chart of one embodiment of the method of the present invention.

FIG. 3 is an explanatory diagram illustrating a robot operation restart method according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram of a method of obtaining an intersection of a tangent line at a sudden stop command position on a robot movement trajectory and a second path in a straight line and a corner portion formed by the straight line in the embodiment.

FIG. 5 is an explanatory diagram of a method of obtaining an intersection of a tangent line and a second path at a sudden stop command position on a robot movement trajectory in a corner portion formed by a straight line and a circular arc in the embodiment.

FIG. 6 is an explanatory diagram of a method of obtaining an intersection of a tangent line and a second path at a sudden stop command position on a robot movement trajectory in a corner portion formed by a circular arc and a straight line in the embodiment.

[Explanation of symbols]

 1 Robot movement trajectory at corners P1, P2, P3 Teaching point S0 Sudden stop command position Se Robot sudden stop position

Claims (6)

[Claims] 1. A method of resuming a robot operation after a sudden stop of a robot, wherein a sudden stop command position at a time point when the sudden stop command is input is stored, and a speed set at the stored sudden stop command position by the robot operation restart command. When the teaching path is a corner of a straight line or a straight line joint or a straight line and a circular arc joint and the sudden stop command position is not on the teaching route, the tangent line at the sudden stop command position on the robot movement locus is And an intersection between the taught first route forming the corner and the second route in the following second route is determined, and the intersection is used as an intermediate point, and instead of the start point and the end point of the first route, A route with the sudden stop command position as the start point and the intermediate point as the end point is set, and the robot operation is restarted from the sudden stop command position with the intermediate point as the start point instead of the start point of the second route. How to restart the robot after a sudden stop. 2. The midpoint of the intersection of the tangent line and the second path is parallel to the linear teaching path on the plane including the taught first and second paths, and is located at the sudden stop command position. The intersection between the passing line and the other teaching route is obtained, and the intersection and the sudden stop command position are taken as one side, and the abrupt stop command position, the intersection point, and the joint between the taught first and second routes are apexes. Then, the vertices on the above-mentioned second path when the parallelogram is defined as are, and the distance from the starting point of the second path is equal to the distance obtained by doubling the distance between the starting point of the above-mentioned second path and the above-mentioned vertex. The method for restarting after a sudden stop of the robot according to claim 1, wherein the robot is located on the path. 3. The method according to claim 1, wherein the intermediate point is a point on the second route in which a correction amount based on the angle of the seam is added to the intersection of the second route and the tangent line. How to restart the robot after a sudden stop. 4. In a method of resuming robot operation after a sudden stop of a robot, a sudden stop command position at the time of input of a sudden stop command is stored, and the robot operation restart command causes the teaching path to be a joint between straight lines and straight lines. At the corner portion of the arc joint, when the sudden stop command position is not on the teaching route, the sudden stop command position is moved at the speed set to the stored sudden stop command position, and on the route of the teaching program close to the sudden stop command position. A restart method after a sudden stop of a robot, in which a position is obtained, the position is moved from the sudden stop command position to the position, the start point of the path of the teaching program having the position is replaced with the position, and the robot operation is restarted from the position. 5. In a method of resuming robot operation after a sudden stop of a robot, a sudden stop command position at a time point when a sudden stop command is input is stored, and the robot operation restart command causes a teaching path to be a joint between straight lines and straight lines. When the sudden stop command position is not on the taught route at the corner portion of the arc joint, on the plane including the taught first and second routes, the sudden stop command position is parallel to the linear taught route. The intersection point of the line passing through and the other teaching path is obtained, and the stored sudden stop command position is moved at the set speed, and then moved to the intersection point, and the starting point of the path of the teaching program having the intersection point is set to the intersection point. Instead of the above, a method of restarting the robot operation after restarting the robot operation from the intersection. 6. A method of resuming a robot operation after a sudden stop of a robot, wherein a sudden stop command position at a time point when the sudden stop command is input is stored, and a speed set at the stored sudden stop command position by the robot operation restart command. When the teaching path is at a corner where the teaching path is a straight line or a straight line joint or a straight line and a circular arc, and the sudden stop command position is not on the teaching route, the seam is moved at the speed set from the sudden stop command position. A method of resuming after the robot is suddenly stopped by moving the robot to that position and restarting the robot operation from the position.