JPH11165291A - Safety monitor and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid an accident by outputting an alarm when a man or an object intrudes a working range of a robot while the industrial robot works. SOLUTION: Positional information of a robot and an object existing in its circumference and a working range of the robot are previously memorized, a distance of the object in a detection range is measured by scanning a sensor 2 when monitoring is started, whether the object intrudes or not is judged by comparing its measurement information with an initial value, whether the object is in the working range of the robot or not is judged by converting information of the sensor 2 to information of a coordinate system around the robot as its center when the object intrudes, and an alarm is output when the object is in the working range of the robot.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety monitoring device for issuing an alarm and preventing an accident from occurring when a human or an object enters the operating range of an industrial robot while the industrial robot is operating.

[0002]

2. Description of the Related Art As one of conventional safety monitoring devices for industrial robots, a device has been devised which uses a camera to detect an object entering a robot operating range in a non-contact manner (Japanese Patent Publication No. 7-81677). ). The technique will be described with reference to FIG. In the drawing, reference numerals 51 to 54 denote cameras fixed to a ceiling or the like in a space above the welding robot 57 placed on the floor and the jig table 58, and 55 denotes cameras 51 to 54.
56 is a safety monitoring device that receives the signals of
Is a monitoring area that can be monitored. Although the measurement target surfaces of the cameras 51 to 54 are rectangular, the welding robot 57 and the jig
To monitor the area around 8, you need multiple cameras,
As shown, four cameras are provided at the top. The images of the monitoring area 56 monitored by the cameras 51 to 54 are taken into the safety monitoring device 55, subjected to image processing, and processed.
It is determined whether or not an object has invaded. Then, when an intrusion of an object is detected, alarm information for stopping the robot or taking an avoidance action is output.

[0003]

However, in the prior art, since the field of view is rectangular and narrow because a camera is used, a plurality of cameras must be installed to monitor a wide area, and the system is expensive. In addition, there is a problem that an installation space for installing the robot above the robot is required, and the installation work requires time and labor. Also, if you output an alarm when an object enters the field of view of the camera,
Since not everything in the camera's field of view is the robot's motion range, an alarm may be output even outside the motion range. However, no alarm is output, and the camera is installed in consideration of such a problem. Therefore, not only is the installation of the camera difficult, but also the reliability of the alarm output is insufficient. On the other hand, when a scanning type distance sensor described in Japanese Patent Application Laid-Open No. 7-98379 applied in the present invention is used to detect an intruder in the monitoring area, the sensor is simply installed at the same position as the robot. Therefore, there is a problem in that the operation rate of the robot must be stopped during the installation and maintenance of the sensor, so that the operation rate of the robot is reduced, and it is difficult to secure a space for installing the sensor. Accordingly, an object of the present invention is to provide an inexpensive and space-saving safety monitoring device that detects that an object has entered the operating range of a robot and outputs an alarm, in order to avoid the above-described problem.

[0004]

According to a first aspect of the present invention, there is provided a safety monitoring device for monitoring the intrusion of an object into an operating range of an industrial robot. A data input unit for inputting initial position data of the robot and objects around the robot, a sensor signal input unit for receiving information of a scanning distance sensor installed near the robot, and a data input unit. Information, information of the sensor signal input means, a memory for storing at least one of these secondary information in advance, and comparing the information of the memory with the information measured by the sensor or the secondary information thereof. Comparing and determining means, a coordinate converter for performing coordinate conversion of information of the data input means or the sensor signal input means, the data input means, and the sensor A signal input means, and said memory,
Controlling the comparison determining means and the coordinate converter to determine whether an object has entered the detection range of the sensor, and further determine whether or not the object has entered the operating range of the robot; It is characterized by comprising a central controller for outputting alarm information when an object has entered the operating range, and alarm output means for receiving information from the central controller and issuing an alarm. According to a second aspect of the present invention, there is provided a safety monitoring device for monitoring a scanning type distance sensor provided in the vicinity of an industrial robot and monitoring that an object has entered the operating range of the robot using the information. Storing the position information of the robot and the objects present around the robot and the operating range of the robot, and setting an initial value;
When monitoring starts, scan the sensor to measure the distance,
The measured information is compared with the initial value to determine whether an object has entered.If the object has not entered, the measurement is continued.If the object has entered, the sensor information is centered on the robot. To determine whether the object is within the operation range of the robot, continue the measurement if it is not within the operation range, and output an alarm if it is. A safety monitoring method for a safety monitoring device characterized by the following. In this way, the safety monitoring device of the present invention is installed at a position away from the robot,
Since it is monitored whether an object has entered the operation range of the robot, it is possible to reliably monitor entry into the operation range without imposing a load on the robot.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the safety monitoring device of the present invention, FIG. 2 is a perspective view showing a monitoring status of a robot, FIG. 3 is a flowchart showing a flow of processing of the safety monitoring device, and FIG. FIG. 3 is a diagram illustrating a positional relationship between a sensor and a robot. In the figure, reference numeral 2 denotes JP-A-7-98.
No. 379, which is installed in the vicinity of the robot so that the robot 3 and its operation range 4 are included in the measurement range 5, and outputs detected information to the safety monitoring device 1 of the present invention. . The sensor 2 scans the laser beam horizontally and vertically, and detects the position of the object based on the detection state of the reflected light, that is, the horizontal angle of the object viewed from the sensor 2 and the vertical angle, from the sensor 2 to the object. Can be quantitatively detected.
Reference numeral 13 denotes a data input interface as data input means for inputting data using a keyboard or a communication means. Reference numeral 11 denotes a sensor input / output interface as sensor signal input means for receiving information of the sensor 2. Reference numeral 14 denotes a data input interface. Information, information of the sensor input / output interface 11, and a memory in which at least one of these secondary information is stored in advance, 15 is information of the memory 14 and information measured by the sensor 2 or 2
A comparison / determination unit 16 serving as a comparison / determination unit for comparing the next information with the next information. Reference numeral 16 denotes a coordinate converter for performing coordinate conversion of information of the data input interface 13 or the sensor input / output interface 11. 10 controls the data input interface 13, the sensor input / output interface 11, the memory 14, the comparison / determination unit 15, and the coordinate conversion unit 16 to determine whether an object has entered the detection range of the sensor 2, Further, it is a central controller that determines whether or not the object has entered the operating range of the robot, and outputs alarm information if the object has entered the operating range. Reference numeral 12 denotes an alarm output interface as alarm output means for receiving the information and issuing an alarm, and has a function of generating an alarm sound, turning on or blinking an alarm lamp, and outputting an alarm signal. When this signal is input to the control panel of the robot 3, the operation of the robot can be stopped or the avoidance operation can be performed without hitting the object. The above components, that is, the data input interface 13, the sensor input / output interface 11, the memory 14, the comparison / determination unit 15, the coordinate converter 16, the central controller 10, and the alarm output interface 12 form the safety monitoring device 1. I have. The safety monitoring device 1 having such a configuration operates as follows. First, in the initial value setting step of S1, position information of the robot 3 is input. For this information, a value measured by a ruler or some distance measuring means may be input using input means such as a keyboard, or may be input using some communication means,
Further, information measured using the sensor 2 may be input. Then, the positions of all objects including the robot 3 and within the measurement range of the sensor 2 with respect to the sensor 2 and the robot 3
Enter the operation range of as the initial value. Next step S2
Now start monitoring. This monitoring may be started by manual input via the data input interface 13, may be started by a signal from an external device such as a control device of the robot 3, or may be started by another method. In step S3, the sensor 2 scans the laser beam, and the measurement range 5
The position of the object in the inside is measured, and the position information is taken in from the sensor input / output interface 11. In step S4, the information of the sensor 2 is compared with the position information of all objects within the measurement range 5 stored in the memory 14 in advance, and whether or not the information is different from the initial value, that is, there is something other than the existing object It is determined whether or not. If there is no object other than the existing object, the process returns to step S3, and the distance is measured repeatedly. The process proceeds to step S5 when it is determined in step S4 that there is an object other than the existing object. In this step, the information of the sensor 2 fetched through the sensor input / output interface 11 is converted by the coordinate converter 16. The conversion will be described with reference to FIG. In this figure, the angle θ between the installation position 7 of the robot 3 and the detected object 6 as viewed from the sensor 2 and the distance L are positional information of the detected object 6 detected by the sensor 2. Based on this information and the distance between the sensor 2 and the robot installation position 7 stored in the memory 14, the positional information of the detected object 6 viewed from the robot installation position 7 from the geometrical relationship, that is, from the robot installation position 7, Seen sensor 2 and detection object 6
And the distance R to the detection object 6 are obtained.
Since this relation can be easily obtained by those skilled in the art, the description of the calculation procedure will be omitted. In step S6, it is determined whether or not the detected object 6 is within the operation range 4 of the robot 3 stored in the memory 14 based on the coordinate-transformed information. If the detected object 6 is not within the operation range 4 of the robot 3, the process returns to step S3 and the measurement by the sensor 2 is continued. The process proceeds to step S7 when the detected object 6 is within the operation range 4 of the robot 3 in step S6. In this step, the central controller 10 outputs an alarm, and the alarm is output via the alarm output interface 12, and the alarm output interface 12 turns on, blinks, or generates an alarm sound. Select the necessary means such as to generate an alarm.
Then, the external device that has received the alarm, for example, the robot 3
Can stop the operation of the robot 3 or cause the robot 3 to avoid the collision with the detected object 6, thereby avoiding an accident. In step S8, it is determined whether or not to continue the monitoring. If the monitoring is to be continued, the process returns to step S3 to continue the measurement of the sensor 2, and if not, a series of operations of the safety monitoring device 1 is stopped. Whether or not to continue may be determined by giving a command from an external device via the data input interface 13 or by inputting from a keyboard or the like by a person.
As described above, an accident caused when a person such as a worker or another working device invades the operation range 4 of the robot 3 while the robot 3 is operating is avoided by quickly detecting the intrusion. be able to. The fact that the robot 3 operates freely within the operation range 4 and may differ from the initial value set in step S1 is as follows.
In any state, since the robot 3 is continuously connected from the base portion to the tip of the arm, the central controller 10 determines that the portion continuous from the base portion is regarded as the robot 3, The robot 3 may not be regarded as an intruding object in any state.
The virtual operation range 4 may be set slightly outside the physical operation range in which the arm tip of the robot 3 can move, and in step S6, the entire range in which the robot 3 can move may be set to be a dead zone. . Such measures can be used in any other way. With these hands,
The monitoring function described above is performed correctly. The above-described series of operations of the safety monitoring device 1 can be incorporated so as to continue monitoring even after an intruding object is detected and an alarm is output, and when it is determined that there is no object other than an existing object, The stopped state of the robot 3 or the avoidance operation can also be canceled. In the above description, the case where only one sensor is used is shown. However, according to the gist of the present invention, the number of sensors is not limited to one, and a plurality of sensors can be used. For example,
By arranging three sensors around the robot 3 and operating them at the same time and performing the same processing, the other sensors can cover the blind spot of the robot that occurs when only one sensor detects, and more reliable monitoring. Can be easily understood. In the above-described embodiment, the sensor 2 and the safety monitoring device 1 are shown as separate devices. However, it is obvious that these may be integrated.

[0006]

As described above, according to the present invention, it is possible to detect that a person, such as a worker, has entered the operating range of the robot, and to promptly output information for avoidance. Thus, there is an effect that an accident is not caused, and the operation rate of the robot 3 is not impaired by the accident and a person is not injured. Further, the safety monitoring device according to the present invention has an effect that a space for installation can be reduced as compared with a conventional monitoring device, and the safety monitoring device can be provided at a low cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a safety monitoring device according to the present invention.

FIG. 2 is a perspective view showing a use state of the safety monitoring device.

FIG. 3 is a flowchart showing a scanning procedure of the safety monitoring device.

FIG. 4 is a diagram showing a positional relationship between a robot and a sensor.

FIG. 5 is a perspective view showing a use state of a conventional safety monitoring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Safety monitoring device 10 Central controller 11 Sensor input / output interface 12 Alarm output interface 13 Data input interface 14 Memory 15 Comparison / determination unit 16 Coordinate converter 2 Scanning distance sensor 3 Robot 4 Robot operation range 5 Sensor measurement range 6 Detection Object 7 Robot installation position

Claims (2)

[Claims] 1. A safety monitoring device for monitoring that an object has entered the operating range of an industrial robot, wherein data for inputting initial position data of the robot and objects in the vicinity thereof using a keyboard or communication means. Input means, sensor signal input means for receiving information of a scanning distance sensor installed near the robot, information of the data input means, information of the sensor signal input means, and at least one of these secondary information A memory in which one is stored in advance, comparison determination means for determining by comparing information in the memory with information measured by the sensor or secondary information thereof, the data input means or the sensor signal input means A coordinate converter for performing coordinate conversion of the information of the above, the data input unit, the sensor signal input unit, the memory, the comparison determination unit, Controlling the coordinate converter to determine whether an object has entered the detection range of the sensor, and further determine whether the object has entered the operation range of the robot. A safety monitoring device, comprising: a central controller that outputs alarm information if the vehicle has entered, and alarm output means that receives information from the central controller and issues an alarm. 2. A safety monitoring device provided in the vicinity of an industrial robot and a monitoring device for monitoring that an object has entered the operating range of the robot using the information of the scanning distance sensor. Position information of the object existing in the
When the operation range of the robot is stored and an initial value is set, when monitoring is started, the sensor is scanned to measure a distance, and the measured information is compared with the initial value to determine whether an object has entered. If the object has not entered, the measurement is continued.If the object has entered, the sensor information is converted into information of a coordinate system centering on the robot, and the object enters the operation range of the robot. A safety monitoring method for the safety monitoring device, characterized in that it is determined whether or not the operation is within the operation range, and the measurement is continued if the operation is within the operation range, and an alarm is output if the operation is within the operation range.