JP5229902B2 - Safe position detector with intrusion detection function - Google Patents

Description

  The present invention relates to a safe position detection device with an intrusion detection function, and more particularly to a safe position detection device with an intrusion detection function that can enable an operator to work safely even when approaching a robot.

  The main cause of occupational accidents involving workers in industrial robots is contact accidents between robots and workers. In order to prevent this, safety protection measures based on safety guidelines have been established based on occupational safety and health rules based on the Industrial Safety and Health Act and international safety standards. In particular, it is necessary that there is no error in the position detection of workers in factories.

  For example, install a safeguard fence around a sufficient distance from the movable range of an industrial robot to surround it, and install a beam-type safety device or mat switch at the opening such as an entrance / exit to operate the robot. It is obliged to prevent workers from entering the movable range.

  In addition, as a definition of the movable range at that time, considering the possibility of robot runaway, it is determined that the area is limited by a mechanical or electrical stopper, not by the robot control program. ing.

  As described above, severe restrictions are imposed on the installation method of industrial robots, so there has been a mistake in the conventional robot automatic operation, or a series of operations have been completed and it has become necessary to change the setup or supply parts. In such a case, it is necessary to completely stop the operation of the robot in order for the worker to enter the movable range and work on the work table, which causes a significant reduction in the operation rate and work efficiency of the robot.

  In order to solve this, for example, the movable range of the robot is divided into a plurality of protected areas by a movable stopper, and when a person enters each protected area, the robot's entry into the corresponding protected area is stopped. In each protection section, a robot braking device and a braking method have been proposed that allow a robot and a person to work in a switched manner and minimize a decrease in the operation rate of the robot (Patent Literature). 1).

  However, in this method using the movable stopper, it is difficult to set the arbitrary movable range in two dimensions or three dimensions because the movable range of all the movable parts of the robot cannot be restricted collectively. .

  Also, for example, when the robot consists of many joints and the range of movement is difficult to understand, or when the work object is handled or the hand tool is changed, the actual size becomes larger than the original robot In some cases, the movable range of the robot is wider than expected, resulting in a disaster due to an unexpected collision with the worker.

  Moreover, there is a problem that it is not possible to prevent a disaster due to contact if the robot already exists and an operator enters the working area only by stopping the approach of the robot.

  As another method, when an intrusion detection sensor is provided in the work area of the robot to detect the operator's intrusion and stop the operation of the robot to make it safe, the robot movement range is similar to the above example. There was a risk of unexpected collisions when it was difficult to understand or when it was unexpectedly large.

  In order to prevent such unexpected collisions using the conventional method, it is necessary to estimate the expected range of movement of the robot considerably large and make the invasion prohibition area set by the sensor sufficiently wide. It is difficult to work in close proximity to each other, or to divide both work areas in three dimensions or in time, which hinders efficient work.

  In other words, in order to improve the operation rate and work efficiency of industrial robots, there is a need for a means to create a coexistence work environment that allows people and robots to coexist in close proximity and work safely even when they are replaced at any time. It was.

  In view of this, the present inventors have already proposed a human robot coexistence safety device that uses an intrusion detection sensor so that a human and a robot can coexist safely (see Patent Document 2). Regardless of the structure of the robot, this device reliably and easily sets the movable range of the robot and the invasion prohibited area of the worker to any two-dimensional or three-dimensional area by using the sensor and the safety controller. The prohibited area can be changed at any time. As a result, even in an environment in which the robot and the worker are close to each other or work in a time-shifted manner, a safe and efficient work can be performed.

  In addition, the present inventors have developed a high-speed vision safety area sensor that realizes next-generation production robots: detecting encoded light markers that blink at high speed in a vision system using high-speed cameras, and detecting errors in marker position and occlusion A highly reliable position detection system that performs detection has been proposed (see Non-Patent Document 1).

JP 63-28591 A JP 2007-283450 A

AIST press release (October 22, 2008), http: /www.aist.go.jp/aist j / press release / pr2008 / pr20081022 / pr20081022 / html

  The human robot coexistence safety device described in Patent Document 2 can detect the intrusion of the worker, but cannot detect the position of the worker. Therefore, it is impossible to work close enough to the robot in terms of ensuring safety.

  On the other hand, the position detection system described in Non-Patent Document 1 can detect a person's position and can work close enough, but cannot detect that a person without a marker approaches the robot. Therefore, it is necessary to combine with an intrusion detection sensor as described in Patent Document 2 and there is a problem that costs increase.

  In view of the above-described conventional problems, the present invention realizes a safe position detecting device with an intrusion detection function that can detect an operator's intrusion and can detect the position of the operator with an extremely simple configuration. Let it be an issue.

  In order to solve the above problems, the present invention provides a plurality of markers for intrusion detection sensors arranged along a boundary line separated from a robot by a predetermined distance and constituting a light curtain, and a human position detection sensor attached to a person. And a safe position detection device with an intrusion detection function comprising a light receiver that receives light from the marker for intrusion detection sensor and the marker for human position detection sensor, and the light from the marker is Provided is a safe position detection device with an intrusion detection function, which is a digitally encoded optical signal having a predetermined code pattern.

  The markers for the plurality of intrusion detection sensors constituting the light curtain are reflective markers that reflect the light projected from the lighting device, and the markers for the human position detection sensor attached to the person are reflective markers. Preferably there is.

  It is preferable that the plurality of markers for intrusion detection sensors and the markers for human position detection sensors attached to a person constituting the light curtain are respectively light emitting markers.

  The safety position detection device with an intrusion detection function according to the present invention can detect the intrusion of a worker with a simple configuration and can detect the position of the worker at the same time. Very useful for securing.

It is a figure explaining the structure of Example 1 of the safe position detection apparatus with an intrusion detection function of this invention. It is a figure explaining the structure of the processing apparatus of Example 1 of the safe position detection apparatus with an intrusion detection function of this invention. It is a figure explaining the structure of the modification of Example 1 of the safe position detection apparatus with an intrusion detection function of this invention. It is a figure explaining the whole structure of the safe position detection apparatus with an intrusion detection function which concerns on this invention. It is a figure explaining the structure of Example 2 of the safe position detection apparatus with an intrusion detection function of this invention.

  Embodiments of a safe position detection apparatus with an intrusion detection function according to the present invention will be described below with reference to the drawings based on the embodiments. In the present specification, the term “intrusion” means that a person (or an object) enters regardless of whether or not permission is granted.

  The safe position detection apparatus with an intrusion detection function of the present invention includes an intrusion detection optical sensor (light curtain, marker, etc.) and a human position detection sensor (human position detection marker, etc.), It is the structure which detects simultaneously a person's position while detecting.

  FIG. 1 is a diagram for explaining the overall configuration of Embodiment 1 of the safe position detecting apparatus with an intrusion detection function according to the present invention. In the first embodiment, a plurality of reflective markers 2 disposed along a boundary line (a line that delimits an entry detection area) that is a predetermined distance away from the robot 1 is disposed as an optical sensor for intrusion detection. The light curtain 3 is constructed. Moreover, the reflective marker 4 is attached to one or several places of a person's clothes as a human position detection sensor.

  The LED illumination device 5 that irradiates light to the reflection marker 2 and the site (place) where the robot 1 is installed is provided, and the reflected light of the reflection marker 2 for intrusion detection is received as an optical signal to be described later. 6 receives light. The optical signal received by the light receiver 6 is processed by a processing device 7 (a computer is used), and the presence / absence of a human intrusion, an intrusion position, and the like are analyzed by a light reception pattern. For example, when a person has entered, in order to block the reflected light of the reflection type marker 2 for intrusion detection, the presence / absence of intrusion and the intrusion position on the boundary line can be detected.

  Further, when a person has entered, the reflection marker 4 attached to the person's clothes reflects the irradiation light from the LED illumination device 5 and enters the light receiver 6 to detect the intrusion and intrusion position. Can do.

  If a plurality of combinations of the LED illumination devices 5 from a plurality of directions and the light receivers 6 corresponding to the LED illumination devices 5 are provided, the intrusion position of a person can be detected in three dimensions.

  In FIG. 1, the LED illumination device 5 and the light receiver 6 are installed at different locations. However, for example, a configuration in which a plurality of LEDs are provided around the light receiver 6 may be integrated. In that case, the reflective marker may be a marker using a retroreflecting material.

  The LED lighting device 5 is connected to the encoder 8. This encoder 8 is an LED light source of the LED illumination device 5 so that the light emitted from the LED illumination device 5 becomes an optical signal that is a code pattern obtained by digitally encoding a predetermined original signal by a predetermined encoding method. The light emission pattern is controlled.

  As an optical signal digitally encoded by a predetermined encoding method, for example, in addition to four signal blocks consisting of 4 bits of the original signal consisting of binary signals that are turned on and off, four signal blocks are used as a Reed-Solomon encoding method. A total of 32 code blocks consisting of 4 error correction code blocks generated in (1) is defined as one unit. Examples of the original signal include an ID number, a time signal, and a sequence number. The light from the LED illuminating device 5 projected in such a light-emitting pattern as a digitally encoded optical signal is reflected by the reflection marker, and the reflected light is received by the light receiver 6.

  By using such a light signal that is digitally encoded with the light emission pattern, the light received by the light receiver 6 includes noise (for example, reflected light or light hiding due to light projection other than the LED illumination device 5). The case can be detected by an error detection decoding process, and if the noise is small, it can be automatically corrected by the error correction decoding process.

  In the present invention, as described above, the code pattern in which the light of the LED light source of the LED lighting device 5 is controlled by the encoder 8 to be actively reduced, and a predetermined original signal is digitally encoded by a predetermined encoding method. The light signal is projected, and the reflected light is received by the light receiver 6, and is decoded by the processing device 7 as shown in FIG. It is possible to correct noise and the like.

  The processing device 7 includes decryption means 9 and analysis means 10, which are actually decrypted by the CPU according to software installed in a storage device (not shown) of the processing device 7 (computer). It is an operation means that performs the analysis function. Alternatively, these means may be means for exhibiting decoding and analysis functions in accordance with hardware logic configured by a digital circuit (eg, FPGA chip (XC3S250E) manufactured by XILINX).

  The decoding means 9 decodes the receiving side code block signal from the light receiver 6 based on a predetermined decoding method, detects an error in the decoded signal block or in the course of the decoding process, or corrects the error. Send to analysis means 10. The analysis means 10 compares the input signal block transmitted from the decoding means 9 with the original signal, analyzes the error detection result or error correction result, and analyzes the presence / absence of a human intrusion, the intrusion position, etc. It is possible.

(Modification)
FIG. 3 is a diagram illustrating an overall configuration of a modified example of the first embodiment. This modified example is substantially the same as the first embodiment, but not only the LED illuminating device 5 but also the laser illuminating device 11 is used as the illuminating device that projects light, and the projected laser beam object. The light curtain 12 is constituted by the light spot 13 by the reflected light from the light, and the reflection type marker 14 is attached to a person.

  In this modification, in addition to the LED illumination device 5, the laser illumination device 11 is also connected to the encoder 8, and not only the LED illumination device 5 but also the light emission pattern of the laser light source of the laser illumination device 11 is controlled, The optical signal is a digitally encoded optical signal having a predetermined code pattern.

  The projected laser light is irradiated along a boundary line separated from the robot 1 by a predetermined distance for intrusion detection, and reflected light from a plurality of light spots 13 constituting the light curtain 12 by reflected light from the object. Both of the reflected light reflected by the reflective marker 14 attached to the person by the light projected from the LED lighting device 5 are received by the light receiver 6. As a result, as in the first embodiment, it is possible to detect the entry of a person and simultaneously detect the position of the person.

  FIG. 4A is a diagram for explaining the overall configuration of a second embodiment of the safe position detection apparatus with an intrusion detection function according to the present invention. The second embodiment is substantially the same as the first embodiment, but is characterized by the following configuration.

  In the first embodiment, a plurality of reflective markers 2 are arranged along a boundary line that is a predetermined distance away from the robot 1 as the light curtain 3 of the photosensor for intrusion detection. The reflective marker 4 is attached to the clothes, and the LED illumination device 5 is configured to project light emitted with a light emission pattern that functions as a transmission signal, and receive the reflected light with the light receiver 6.

  However, in the second embodiment, as the light curtain 14 of the light sensor for intrusion detection, a substrate 16 on which a light emitting marker 15 (eg, LED light emitting device) is mounted is predetermined from the robot 1 as shown in FIG. A plurality of substrates 16 are arranged along a boundary line separated from each other, and a substrate 16 on which a similar light emitting marker 15 is mounted as a human position detection sensor is attached to a person's clothes.

  As shown in FIG. 4B, the light emitting type marker is a digitally encoded light that becomes a predetermined code pattern by a code generator 17 (eg, FPGA chip (XC3S250E) manufactured by XILINX) provided on the substrate 16. The light emission pattern is controlled to emit a signal. The emitted light is received by the light receiver 6. Thereby, it is possible to detect the intrusion of a person and simultaneously detect the position of the person.

  As mentioned above, although embodiment and the Example of the safe position detection apparatus with an intrusion detection function which concern on this invention were described with reference to drawings, this invention is not limited to such an Example, Claim It goes without saying that there are various embodiments within the scope of the technical matter described.

  INDUSTRIAL APPLICABILITY The safe position detection device with an intrusion detection function according to the present invention is extremely useful for safety protection of an operator in an environment where the operator works with a robot, and is not only used for a work robot but also for household use that is desired to be used in the future. It is suitable for environments using robots, robots in the field of nursing care and welfare.

DESCRIPTION OF SYMBOLS 1 Robot 2 Reflective marker 3, 12, 14 Light curtain 4 Reflective marker 5 LED illumination apparatus 6 Light receiver 7 Processing apparatus 8 Encoder 9 Decoding means 10 Analyzing means 11 Laser illumination apparatus 13 Light spot 15 Light emission type marker 16 Substrate 17 Code | symbol Generator 18 Lighting device

Claims (1)

Markers for a plurality of intrusion detection sensors that are arranged along a boundary line that defines an area for detecting entry at a predetermined distance from the robot and that constitute a light curtain, and markers for a human position detection sensor attached to a person A light receiver for receiving light from the marker for the intrusion detection sensor and the marker for the human position detection sensor, and the light from the marker for the intrusion detection sensor and the marker for the human position detection sensor is: In a safe position detection device with an intrusion detection function, which is a digitally encoded optical signal having a predetermined code pattern ,
Marker for human position detection sensor attached to the marker and human for multiple intrusion sensors constituting the light curtain, I Oh each emitting marker,
Each of the light emitting type markers has a light emitting device mounted on a substrate, and by a code generator provided on the substrate, at least an original signal consisting of a binary signal that is turned on and off, an original signal consisting of an ID number, and a time A safe position detecting device with an intrusion detection function , wherein a light emission pattern is controlled so as to emit an optical signal obtained by digitally encoding an original signal composed of a signal into a predetermined code pattern .

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