JPH0265994A - Preventing system for interference of robot - Google Patents

Abstract

PURPOSE:To monitor interference on each interpolation period, to await out of interference zone in case of a likely interference and to reduce interference by having a monitoring algorithm for interference in the interpolation control. CONSTITUTION:The monitoring as to whether or not a robot interferes each other during movement can be done at all times by assembling algorithm into a robot movement logic. Also, the arithmetic result operated for outputting to a servomotor can be done so as not to be output, in case of algorithm interfering, as the result of monitoring, by placing the succeeding moving position prior to the output to the servo. Namely, the robot can be stopped instantaneously accordingly and the succession of the previous operation is performed in case of the robot of the counterside being escaped out of the interference area.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to industrial robots, and is particularly suitable for preventing interference when multiple robots are placed in positions where their operating ranges overlap. Regarding the method.

[Conventional technology]

As described in the attached document, conventional devices were connected externally to the target robot, and their programs were automatically changed in the event of interference.

In addition, as a robot interference prevention method, Japanese Patent Application Laid-Open No. 52-5
The one described in No. 5764 is known.

[Problem to be solved by the invention]

In the prior art, monitoring to prevent interference was performed only before program execution or before execution of an interpolation operation to the next teaching point.

The problems of the prior art will be described below using FIG. 2. now,
Assuming that the working point of the robot 2 is at a teaching point P1 outside the interference area, the robot 2 first determines whether it is interfering or about to interfere at Pl. At this time, if the other robot 2' is at the teaching point PI' outside the interference area of the robot 2', then the robot 2'
It is determined that there is no interference. This is because the only issue for the robot 2 is whether or not the work point of the other robot 2'' is in the interference area.

For the above reason, if it is determined that the robot 2 does not interfere, the robot 2 moves to the next teaching point P2. However, similarly, robot 2' also moves to the next teaching point P2.
Robot 2 moved to ' and reached the next teaching point first.
If the robots 2' have already entered the interference area when the robots 2' and 2' determine interference at P2, they will interfere with each other at that point. Cases like this are not rare;
When interference occurs, the same program is often re-executed, resulting in the same phenomenon occurring at the same location each time. In this case, the reason is that it takes a long time from when the robot 2 checks whether the robot 2' has entered the interference region at Pl until the robot 2 enters the interference region. That is, it is considered that the closer the point at which the state of the robot 2° is checked is to the interference region, the less likely the above phenomenon will occur.

The purpose of the present invention is to use the interpolation period, which is expressed as
The purpose is to constantly monitor the status of the other robot at intervals of 0 [m5ec] to increase operational efficiency.

[Means for Solving the Problems] The above objective can be achieved by monitoring whether interference occurs at appropriately short intervals during the robot operation path. In operating the robot, the position of the next point to be moved is calculated until the next teaching point, and the moving operation is performed by outputting it to the servo by some means.

Therefore, as shown in Figure 1, before outputting a command to the servo, it is checked whether the robot is currently entering the interference area, and if it is, the other robot is in the interference area. Check whether When in the interference region, the robot can be stopped in place by returning to the beginning of the check, and at the same time it is also possible to perform these checks at very short intervals.

[Effect]

By incorporating the algorithm shown in FIG. 1 into the robot movement logic, while the robots are moving, it is possible to constantly monitor whether or not the robots will interfere with each other. In addition, by placing the above algorithm before outputting the next movement position to the servo, if there is interference as a result of monitoring, the calculation result that was calculated to be output to the servo will not be output. It can be done. That is, the robot can thereby immediately stop, and when the other robot escapes from the interference area, it will continue its previous operation.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 3, 4, and 5. As shown in Fig. 3, robot 2 and robot 2' are arranged so that a part of their respective operating ranges overlap, so that the signals output by this method are input to the other robot. Each is connected. Furthermore, each robot has a control structure shown in FIG. 4, and the servo control processing (SVP) 6 in the figure has an algorithm based on this method. Now, the area to be interfered with has been incorporated into the robot in some way, and the work point of robot 2 (2") is at PI (P1'), and P2
Trying to move in a straight line to (P2'). here,
If we follow the flow of interpolation in robot 2 according to Figure 4, we will first calculate the next point to move to, determine whether the current position of the robot is within the interference area, and send that information to the unit interface. (UiF) Write to RAM on 5. This information is stored in the sequence control processing unit (SCP)
Relay Interface (RYiF) 11 by 10
is transmitted to the relay through , and then to the other robot. The next interpolation point here is a coordinate calculated based on the interpolation period, movement speed, etc., and if the interpolation period here is 30 [m5ec], it means the point at which the robot must be moving after 30 [m5ec]. do.

Next, it is determined whether or not the next interpolation point is within the (interference area ±α), and if so, the human input signal is further checked. This signal is relay human power, RYiFll, 5CPIO, UiF
5, and is passed to 5VP6 in the opposite path to the signal output. In the processing up to this point, the robot 2' is within the interference area, and even if the robot 2 attempts to move into the same interference area, it will loop in the processing section of FIG. 5A, so the robot 2 will move to the point P3.
You can wait there. Also, when exiting from the processing section A, the command value is 5VP6, then the servo controller 7,
The signal is output to the robot body through the mechanical interface 8, and the robot moves. After the movement, if the next interpolation point has been reached, this process is repeated until the target position P2 is reached.

According to this embodiment, the interference between two robots is reduced to 30 [m5
ec] can be monitored and prevented.

〔Effect of the invention〕

Since this method incorporates an interference check into the interpolation algorithm, the check is performed at the same period as the interpolation period. Therefore, it is possible to monitor interference every interpolation period (several 10 m5ec) irrespective of position teaching, and to wait outside the area in advance if interference is likely to occur. This reduces interference.

[Brief explanation of the drawing]

Figure 1 shows the algorithm of this method, Figure 2 shows the relationship between the operating range and interference area, Figure 3 shows the connection between robots in an example of this method, and Figure 4 shows the example of this method. Control Structure: FIG. 5 is a flowchart of the interpolation algorithm in one embodiment of the present method. 1... Operating range of robot 2, 1'... Robot 2
' operating range, 2... robot, 2'... robot that is the other party to robot 2, 3... robot 2
interference range, Pl...teaching point outside the interference area of robot 2, PI'...teaching point outside the interference area of robot 2', P2
...Teaching point in the interference area of robot 2, P2'...Teaching point in the interference area of robot 2', P3...Pl and P2
The point outside the interference area that is closest to the interference area, i
...Signal input section of robot 2, i'...Robot 2
Signal input part of ゜, O...Signal output part of robot 2, ○
"... Signal output section of robot 2', α... Margin for stopping the robot outside the interference area. Used to ensure that the robot stops outside the interference area even when operating at maximum speed. 4... Magnetic bubble memory for storing control programs and teaching data, 5... Unit interface, 6... Servo control processing section, 7... Servo system controller, 8... Mechanical interface,
9...boat for accessing 4.5.6.7.10,
DESCRIPTION OF SYMBOLS 10...Sequence control processing unit, 11...Relay interface 2nd concave Figure P2'

Claims (1)

[Claims] 1. An interference prevention method for a robot, which is characterized by having an interference monitoring algorithm in interpolation control so as to monitor interference at each interpolation cycle, and to be able to stand by outside the interference area if interference is likely to occur.