JPS6272005A - Control method for robot - Google Patents

Abstract

PURPOSE:To realize a backward movement stroke of a robot by using a data block group for its forward movement stroke by completing the backward movement stroke at the point of time when an instruction based upon movement data in the 1st data block of the forward movement stroke is executed lastly. CONSTITUTION:When the robot is moved forth, function instructions which instruct the state of the robot in the backward movement stroke are determined while pre-fetched from the data block group for the forward movement stroke. Namely, when there is no opening/closing instruction in a data block right before a data block X, data block groups are checked one after another in the reverse direction of the forward movement stroke until it is judged that the opening/closing instruction is present in a step (e). Consequently, the backward movement stroke is realized along the variation process of the robot in the backward movement stroke. The backward movement stroke along the forward movement stroke is possible by utilizing the data block group for the forward movement stroke, so the data block group for the backward movement stroke need not be generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling a robot, and more particularly, a function including movement data for instructing the position of a robot body or an operating part of the robot, and a command for instructing the state of the robot. In the control method for performing the forward stroke of the robot hand based on each data block consisting of Concerning robot control methods.

In general, in automated production systems, industrial robots do not work alone, but rather take part in a production line and work in conjunction with machines before and after the work process. Further, during work, the operating parts of the robot, such as the arm, hand, and leg mechanism, which are substantially in operation, are controlled according to the content of the work by a control part including a sensor, a computer, and the like.

For example, when transporting a workpiece, a robot moves a hand attached to its arm using a predetermined drive mechanism, and also transports the workpiece by opening and closing the hand. In this type of robot-based transport control, a data block group consisting of consecutive individual data blocks consisting of movement data programmed into a computer to instruct the hand position and functional data including hand opening/closing commands. A method is adopted in which the operation is performed based on the following.

FIG. 1 shows an example of a data block group for controlling the robot's motion using such a method. As shown in the figure, each of data blocks 1 to 7 constituting the data block group for the forward movement consists of movement data and functional data. The movement data includes position data for instructing the position of a hand as an operating part of the robot within the work space. In this case, the position data is indicated as positions A to G. On the other hand, the functional data basically includes functional commands for instructing the state of the robot, and in this case, an opening/closing command for instructing opening/closing of the hand is used as the functional command.

However, the opening/closing command is not necessarily included in the function data. That is, data block 3 and data block 7 do not have open/close commands. If there is no opening/closing command as described above, the opening/closing of the hand is not instructed, so the open/closed state of the hand does not change.

Also, when commands are issued using each data block,
Generally, after a command based on movement data is issued, a command based on functional data is issued. The computer sequentially reads out the movement data included in these data blocks to displace the arms that make up the robot, and controls the opening and closing of the hand by reading out the functional data.

Next, the forward movement according to the data block group of FIG. 1 will be explained with reference to FIG. 2. Note that the solid lines including arrows shown in FIG. 2 indicate the operating process in which the open and closed states of the hand are shown in correspondence with positions A to G.

First, the forward process starts from data block 1. That is, a state in which the hand is closed at position A is set by the movement data and function data of data block 1. Next, the hand is moved to position B according to a command from data block 2, and then the hand is opened.

It should be noted that this action of opening the hand is shown in FIG. 2 by an arrow pointing upward in the figure.

The hand opened at position B moves to position C by reading data block 3.

In this case, data block 3 does not have an open/close command, so
The hand remains open. Then, by reading the data block 4, the hand moves to the position and closes. This is how the hand closes.
In the figure, it is indicated by an arrow pointing downward in the figure.

Next, data block 5 moves the hand to position E, and since the opening/closing command at that time is the same hand closing as the opening/closing command of data block 4, the closed state of the hand does not change. Further, by reading the data block 6, the hand moves to position F, and then the hand is closed.

The hand opened at position F is moved to position G by data block 7. In this case, since there is no open/close command in the data block 7, the open state of the hand is maintained.

That is, as shown in Fig. 2, the hand in the forward movement described above is closed at position A, then opened at position B, closed at position B, and then opened again at position F, and then moved to position K in the open state.
Move to G.

Although the workpiece is conveyed by repeatedly gripping and releasing the workpiece as described above, there may be cases where it becomes necessary to temporarily return the robot to its original position due to an accident or the like.

Therefore, the operation process of the hand when the backward stroke from data block 7 to data block I is performed in the reverse order of the forward stroke after completing the forward stroke will be described below.

First, the open hand at position G moves to position F by reading the data profile. Position F
In , the function data of data block 6 is hand closed, so the open state of the hand does not change. Next, data block 5 moves the hand to position E and closes it.

Then, the hand moves to the position according to the data block 4. Since the functional data in this case is hand closed,
The hand remains closed.

The hand, which is closed in position, is moved to position C by data block 3. At this time, since there is no open/close command in the data block 3, the closed state of the hand is maintained. Next, after the hand moves to position B by reading data block 2, the hand is opened by the hand open command in this case. Furthermore, data block 1 moves the hand to position A and closes it. The backward stroke in which the data block group for the forward stroke is executed in the reverse flow is as described above, and this backward stroke is shown as the first backward stroke in FIG. 2.

However, as described above, if the data blocks for the forward process are sequentially read out during the backward movement, the following disadvantages arise. For example, if we compare the forward stroke and the first backward stroke in FIG.
In other words, when executing a data block group for a forward stroke consisting of movement data and functional data as described above in the opposite direction, it is impossible to realize a backward stroke along the movement process of the hand in the forward stroke. be. This means that, for example, even though the hand was gripping the workpiece between positions D and F in the forward stroke, the workpiece was not gripped because the hand was open at position INF in the first backward stroke. It means not there.

Therefore, in order for the forward stroke and the backward stroke to follow the same operating process, it is necessary to program a data block group for the backward stroke that is different from the data block group for the forward stroke. After all, in order to execute a backward stroke that reverses the movement process of the hand in the forward stroke, even if a data block group for the forward stroke has been programmed in advance, a data block group dedicated to the backward stroke must be programmed. I have to keep it.

As mentioned above, general data blocks for robot control include movement data for instructing the position of the robot's hand or operating parts such as the robot body, and functions for instructing the state of the hand, such as opening and closing. command or function data including data indicating the absence of the function command. In other words, when performing a backward stroke using a data block group for forward strokes in which such data blocks are connected, simply executing the data block group for forward strokes in the reverse direction will allow the robot to move forward and backward. The process of state change in will be different. Therefore, in order to realize a backward stroke that faithfully follows the state changes in the forward stroke of the robot, it is necessary to provide a data block for the backward stroke separately from the data block group for the forward stroke. For this reason, if the data block group for the forward stroke is a long program, programming the data block group for the backward stroke becomes extremely complicated, which not only increases the cost but also increases the storage capacity of the computer all at once. I don't get it.

Therefore, as a result of intensive research and ingenuity, the inventor of the present invention found that
When executing a backward stroke from the first data block in the data block group for the forward stroke, if there is no function command that instructs the state of the robot in the first data block, the second data block immediately before the first data block is Execute an instruction based on the moving data in the data block, and if there is a functional instruction in the first data block, read the functional instruction included in the previous and closest data block to the first data block; After executing the functional command, the first
If the data blocks for the forward process are followed in reverse so as to sequentially repeat the control of executing instructions based on the movement data in the data block immediately before the data block, the backward process will be executed in accordance with the state change process of the forward process. As a result, it is no longer necessary to create a new data block group for the backward stroke, and it has been found that all of the above-mentioned inconveniences are eliminated.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for controlling a robot that is capable of realizing a backward stroke in accordance with the change process of the robot in the forward stroke using a data block group for the forward stroke of the robot.

To achieve the above object, the present invention provides movement data for instructing the position of an operating part of a robot, and a function command or the functional command for instructing in which state the operating part of the robot is. When performing the robot's backward stroke by using a data block group for the robot's forward stroke, which consists of multiple consecutive data blocks consisting of function data including data that means that there is no If not, the second data profile immediately before the first data profile is
, and if there is a first functional instruction in the first data block, the instruction is executed based on the movement data in the first data block.
It is determined whether a second function command in a data block near the data block matches the first function command, and if the first function command and the second function command match, the state of the operating part of the robot is determined. execute an instruction based on the movement data in the second data block without changing the second data block, and if the first functional instruction and the second functional instruction do not match, execute the second functional instruction after executing the second functional instruction. The instructions based on the movement data in the data block are executed, and the above control is repeated sequentially to trace the data block group for the forward process in the reverse direction, and finally, the data blocks in the first data block of the forward process are The present invention is characterized in that the backward stroke is completed at the time when the command based on the movement data of is executed.

Next, preferred embodiments of the robot control method according to the present invention will be described in detail with reference to the accompanying drawings.

The flowchart of FIG. 3 shows the basic flow of subroutines programmed into a computer to carry out the method of the present invention on data blocks relating to the position and opening/closing of the robot's hand. Therefore,
Next, the process will be explained along the flowchart shown in FIG. 3.

When starting the backward stroke from data block X, first,
It is determined whether or not it is X-1 (STPa). However, in this case, X means the data block number. That is, in step a, it is determined whether data block X is the first data in the forward process. If X is not 1 in step a, it is determined whether there is an open/close command in data block X (STPb).

Therefore, if there is no open/close command for data block X, step i, which will be described later, is executed.

On the other hand, if an open/close command exists in data block X, the open/close command for data block X is read into a first register in the computer (STPc).

Next, as Y-X (STPd), it is determined whether the data block immediately before the cheater block X, that is, the data block (Y-1), has an open/close command (STP
e). In step e, data block (Y-1)
If there is an open/close command in that data block (Y-
1) Read the open/close command into the second register (STPf
). Therefore, it is determined whether the open/close command read into the second register in step C matches the open/close command read into the second register in step f (S
TPg). If the two opening/closing instructions compared in step g do not match, the opening/closing instruction for the second register is output (STPh).

That is, the hand opens and closes in step h.

Next, in order to move the hand that has been at the position of the movement data of the cheetah block X up to this point to the position corresponding to the movement data of the data block immediately before data block (STPi). That is, step i moves the hand to the previous position. Note that if the two opening/closing commands compared in step g match, step i is executed following step g. Furthermore, if there is no open/close command in the data block (Y-1) in step e, it is determined whether the data block (Y-1) is Y-1-1 (STPj
).

If Y-1 is not 1 in step j, then (S
TPk), execute again from step e. That is, if there is no opening/closing command in the data block immediately before data block X, the data blocks are examined one after another in the reverse direction of the forward movement until it is determined in step e that an opening/closing command exists. Following step i, in order to continue the backward process from the data block (X-1),
X=X-1 (5TPl), and execute again from step a. Then, when X=1 is finally reached in step a, the backward stroke is completed.

The robot control method according to the present invention is basically carried out according to the steps described above. Next, a backward stroke from the data block 7 executed by applying this robot control method to the data block group shown in FIG. 1 will be explained. Note that the backward stroke to be described next is shown as a second backward stroke in FIG.

In this case, at position G, which is the final position of the forward movement,
Hands are open. First, since it is X-7, step b is executed following step a. data block 7
Since there is no opening/closing command, the judgment result in step b is NO.
and step i is executed. That is, the hand moves to position F of data block 6 while maintaining the open state of the hand. Following step i, X-6 is set in step l, and steps a and b are executed again. Since data block 6 has an opening/closing command, the determination result in step b is YES, and in step C, data instructing to open the hand of data block 6 is read into the first register. Next, through step d, it is determined in step e whether or not there is an open/close command in the data block 5. Since the result of this determination is YES, step f is executed. That is, the data instructing hand closure in data block 5 is read into the second register. and,
In step g, it is determined whether the open/close command for data block 6 and the open/close command for data block 5 match;
The result of this determination is No. Therefore, step h outputs the hand close command of data block 5, and the hand closes at position F. Next, the hand moves to position E of data block 5 in step i. Furthermore, X-5 is set in step 1, and steps a and b are executed.

Since data block 5 has an open/close command, step b
The result of the determination is YES, and in step C, the hand close command of data block 5 is read into the first register. Further, since data block 4 has an open/close command, the determination result in step e is YES, and step f reads the hand close command in data block 4 into the second register. Therefore, in step g, data block 5 is
It is determined whether the opening/closing command of the data block 4 matches or not, and the result of this determination is YES. Therefore, following step g, step i is executed. That is,
The hand moves from position E to position while remaining closed.

Thereafter, in step b, which is executed through steps l and a, the determination result is YES because there is an open/close command in data block 4, and step C is executed. Therefore, the hand close command of data block 4 is read into the first register. In step e, it is determined whether there is an open/close command in data block 3, and the result is NO. Subsequently, since the determination result in step j is NO, it is determined in step e that passes through step k that there is an open/close command in data block 2. Therefore, in step f, the hand close command for data block 2 is determined. is read into the second register. Following this, step g
Then, it is determined that the opening/closing commands of data block 4 and data block 2 do not match. Then, in step h, the hand closing command of data block 2 is executed, and the hand is opened at the position, and further, in step l, the data block is closed. The hand moves to position C of 3.

Next, in step b after passing through step β and step a, it is determined that there is no open/close command in the data block 3. As a result, the open hand moves from position C to position B by step i. Yet another step!
, after step a, step C is executed following step b because there is an open/close command in data block 2.

That is, the hand close command of data block 2 is read into the first register. In step e, it is detected that data block 1 has an open/close command. Next, step f reads the hand close instruction of data block 1 into the second register. Therefore, in step g, it is detected that the opening/closing commands of data block 2 and data block 1 do not match. Then, in step h, the hand close command of data block l is executed, so the hand is closed at position B.

Furthermore, by executing step i, the hand moves to position A of data block 1.

Next, step 2 becomes X-1, so step a
The judgment result is YES and the backward stroke is completed. From the above explanation, it will be easily understood that this backward stroke is the second backward stroke shown in FIG.

Therefore, the movement of the hand in the backward stroke to which the method of the present invention is applied follows the movement process in the forward stroke. Although the backward stroke explained above starts from data block 7, it goes without saying that a desired backward stroke can be obtained even if it starts from any data block.

By the way, the above is an explanation of the case where the control method based on the flowchart shown in Fig. 3 is applied to the data block group of Fig. 1 regarding the position and opening/closing of the robot hand. order"
If this flowchart is replaced with a predetermined function command for indicating an incorrect state of the robot, this flowchart can be used for a group of data blocks related to various changes in the state of the robot.

Therefore, the robot control method according to the present invention can also be applied to a data block group having basically the same configuration as the data block group shown in FIG. That is, movement data for instructing the position of the actuating part of the robot, and functional data including a functional command for instructing one of the binary states of the robot or data indicating the absence of the functional command. If this control method is applied to a group of data blocks for the forward stroke of a robot, which consists of a plurality of consecutive data blocks, it is possible to achieve a backward stroke in which the state change process in the forward stroke is performed in the opposite direction. .

Note that even when the above-described data block group is used for an operating part other than the robot's hand, the operating process of the forward stroke and backward stroke may be different. For example, if two robots on a production line are placed close to each other and there is an interference area where the work spaces of each robot overlap, if the two robots move into the interference area within the same time, the robots will collide. Therefore, an interlock permission signal is used to prevent two robots from moving into the interference area within the same time period. The method of the present invention is also used when reading the permission signal for this interlock,
Therefore, it goes without saying that it can also be used to avoid collisions caused by interference between robots.

According to the present invention, as described above, the functional command that instructs the state of the robot in the backward stroke is determined while looking ahead from the data block group for the forward stroke, and as a result, the change process of the robot in the forward stroke is determined. It becomes possible to realize a backward stroke. That is, since the backward stroke along the forward stroke can be performed using the data block group for the forward stroke, there is an advantage that there is no need to create a data block group for the backward stroke.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to these embodiments (various improvements and changes in design are possible without departing from the gist of the present invention). Of course.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a data block group for performing a forward stroke of the robot's hand, FIG. 2 is an explanatory diagram of the operation process of the hand in the forward stroke and backward stroke based on the data block group shown in FIG. 1, FIG. 3 is a flowchart showing a subroutine for implementing the robot control method according to the present invention.

Claims (2)

[Claims] (1) Contains movement data for instructing the position of the actuating part of the robot, and a function command for instructing which state the actuating part of the robot is in, or data meaning that there is no said functional command. When performing a backward stroke of the robot by using a data block group for the forward stroke of the robot, which consists of multiple consecutive data blocks consisting of function data, if there is no function command in the first data block, the state of the operating part of the robot execute an instruction based on the moving data in a second data block immediately before the first data block without changing the first data block; Determine whether a second functional instruction in a data block that is earlier and closest to the first data block matches the first functional instruction, and if the first functional instruction and the second functional instruction match. executes the command based on the movement data in the second data block without changing the state of the operating part of the robot, and if the first function command and the second function command do not match, the second function command after executing an instruction based on the moving data in the second data block,
By sequentially repeating the above control, the data block group for the forward stroke is traced in the reverse direction, and finally, when the command based on the movement data in the first data block of the forward stroke is executed, the backward stroke is started. A robot control method characterized by completing the following steps. (2) In the method according to claim 1, the movement data is data for instructing the position of the hand of the robot, and the function data is an open/close command or an open/close command for instructing the open/close state of the hand. It consists of data that means no command, and if there is no opening/closing command in the first data block in the data block group for the forward process, the second data immediately before the first data block is read without changing the opening/closing state of the hand. Move the hand to the position indicated by the movement data within the block, and on the other hand, if the first data block has a first open/close command, the data block is located before the first data block and is closest to the first data block. It is determined whether or not the second opening/closing command located in Move the hand to the position indicated by the movement data in the data block, and if the first opening/closing command and the second opening/closing command do not match, move the hand within the second data block after executing the second opening/closing command. The hand is moved to the position specified by the data, and the data blocks for the forward process are followed in the reverse direction, repeating the above control sequentially, and finally the hand returns to the starting position of the forward process. A method of controlling a robot comprising completing a backward stroke at a point in time.