JPS61226289A - Diagnostic device for robot-manipulator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a diagnostic device capable of diagnosing failures in robots and manipulators, particularly those that appear on the outside.

``Prior art'' Conventional failure detection in robots and manipulators has mainly been based on electrical and software failure detection, such as detecting abnormalities in computers and memory, and detecting disconnections in drive devices and position detectors. There are no abnormalities in terms of target performance or drive force transmission, but there is little development in detecting external failures such as thin parts or damage to mechanical parts.

``Problems with conventional technology'' For example, devices that require force such as extreme work robots and manipulators are exposed to the risk of damaging the wrist during work, and that some parts may become tax-excluded. In many cases, it may not be possible to stop work midway and return to the waiting area for repairs. It is necessary to perform detection, pinpoint the location of the failure, and promptly perform necessary actions on the spot, such as replacing the wrist or replacing parts, to continue work.

However, the conventional robot failure detection device as described above cannot detect the mechanical failure as described above.

``Object of the Invention'' Therefore, the object of the present invention is to quickly detect failures that appear on the appearance of robots, manipulators, etc.
The goal is to ensure that appropriate treatment can be taken.

"Structure of the Invention" In order to achieve the above object, the main means adopted by the present invention are a television camera attached to a robot manipulator, and a reference attitude control that causes the robot manipulator to assume a reference attitude. means, a figure storage means for capturing an image of the robot manipulator in a reference posture using the television camera and storing the two-dimensional image pattern; and a figure of the robot manipulator that has been imaged and stored in the past by the figure memory means; This is a diagnostic device for a robot manipulator, which includes a failure processing means that compares the appearance of the robot manipulator that was imaged this time and performs failure processing if it is determined that the two images are not the same.

Among the above components, a so-called ITV camera is used as the television camera, and the reference attitude control means is achieved by an attitude control device using a normal servo positioning mechanism. This varies depending on the type of work and the type of work, so the operator can
Operate robots and manipulators with 11 works,
This is done by storing the operating position of the actuator, such as joint angles and cylinder lengths of each robot arm and wrist, and the figure storage means stores the brightness information, color information, distance information, etc. captured by the television camera. The information is stored in a memory as two-dimensional image information (two-dimensional image pattern) digitized by a /D converter of about 4 to 10 bits. Furthermore, the failure handling means may use a posture control device to make the robot/manipulator take a reference posture in advance before the robot/manipulator or the like starts work, take an image of the robot/manipulator in that posture using a television camera, and store the image. This fixed memorized image may then be compared with the appearance of the robot/manipulator that is captured as needed.Also, the robot may be asked to take a reference posture periodically or irregularly during the work. Alternatively, the appearance at that time may be captured and stored, and the appearance in the previous reference posture and the appearance in the current reference posture may be compared each time.

``Example'' Next, examples embodying the present invention will be described with reference to the attached drawings to provide an understanding of the present invention. here the first
The figure is a block diagram showing the signal flow of a diagnostic device according to an embodiment of the present invention, FIG. 2 is a flowchart showing the processing procedure in the diagnostic device, and FIG. 3 is an example of a robot in which the diagnostic device is used. FIG. 4(a) is a perspective view showing an example of an undamaged robot, and FIG. 4(b) is a perspective view showing an example of an undamaged robot.
Plan view of the wrist in the reference posture shown in a), FIG.
4(a) is a perspective view showing the wrist shown in FIG. 4(a) in a damaged state, and FIG. 4(b) is a view corresponding to FIG. 4(b) of the same damaged wrist.

The following examples are merely specific examples of the present invention, and are not intended to limit the technical scope of the present invention.

First, in FIG. 1, the robot control device 10 includes a control panel for remotely operating the robot R to perform teaching work, and a wrist H of the robot R obtained through the teaching work.
a storage device for storing the coordinates of the trajectory, and an arithmetic device for retrieving target value data from the storage device during playback work, performing interpolation calculations and coordinate conversion calculations on this data, and calculating the target angle of each joint. and a control section that servo-controls the robot R according to the target angle output from the arithmetic device. It is composed of a normal robot control device, and in particular, when an operator operates the control panel to guide the robot R to a desired reference posture, the work is performed by attaching it to the main body of the robot L-H and its wrist H in that reference posture. It has the function of storing each joint angle, position image, direction cosine, etc. of the hand T in the storage device as reference posture data, but such a function is simply a storage device of a conventional robot control device. This is achieved by securing an area for holding reference posture data in the area.

In Figure 1, 11 is an ITV camera, which is normally used by robot R.
This is for photographing the elements of the robot (H) fixed to the swivel base S and assuming a reference posture, such as the wrist B and the working hand T.

The image information obtained by the ITV camera is converted into a digital signal of, for example, about 4 to 10 bits by the A/D converter 13, and is converted into an image memory area 1 in the storage device.
4 is stored. Here, the data stored in the image memory area 14 is close to raw information, such as a three-dimensional diagram, captured by the ITV camera 11.

In the present invention, such appropriately captured image information is compared with image information in the standard posture, and the robot l-H
This is to detect the appearance of damage to the exterior of the vehicle, but normally the raw information above is complex and the judgment is unreliable, so the raw information is converted to a pattern such as a plan view or side view. Or, the image is simplified by applying so-called patterning processing to convert it into a pattern for each color.

On the other hand, the reference posture data stored in the storage device is digital data corresponding to a reference pattern obtained by previously performing the patterning process described above on image information in the robot's reference posture, and these reference posture data is compared with the patterned image information in the current standard posture of the robot, and the result is sent to the robot control device 10.
is input.

When the robot control device 10 receives this comparison signal and determines that the current image information is different from the reference posture data, it performs processing such as replacing the work hand T, for example.

For example, when applying the feeding/disconnecting device according to the present invention to a robot R as shown in FIG. -ti image.

If the actual image at this time is, for example, an image as shown in FIG. 4(a), the image memory area 14 will first contain a digital image corresponding to the two-dimensional image shown in FIG. 4(a). Data is stored. This data is further processed through a well-known pattern processing process into digital reference posture data corresponding to a plan view as shown in FIG. 4(b), for example, and stored in another memory area. In this way, patterned reference posture data in the reference posture is collected before actual work is performed.

Next, the procedure for self-diagnosis by the robot in the actual work process will be explained with reference to FIG.

In the actual work process, for example, the program shown in FIG. 2 is run periodically. As shown in FIG. 2, this program includes the robot control device 1
A reference attitude target value for guiding the robot to the reference attitude from 0 is sent, and the robot R is guided to the previously taught reference attitude.

In this state, the robot R remains stopped for a certain period of time, but at this time, the ■Tv camera 11 is
Take an image of the figure. The ITV camera 11 is set in a position direction such that the work hand T of the robot R inevitably comes into its field of view when the robot R assumes the standard posture.

When the two-dimensional image data in the current reference posture is input in this way, this is stored in the image memory area 14, and then patterning processing is performed on this two-dimensional data, for example, an image corresponding to a plan view of the working hand is generated. Information can be obtained. Here, the already patterned reference posture data is searched and compared with the patterned imaging data in the current reference posture, and a comparison signal that is the result is sent to the robot control device 10. In the robot control device 10, when the comparison signal indicates an emergency state, that is, when there is a difference between the reference posture data and the current patterned posture data, the robot control device 10 takes action such as replacing the work hand T, for example. An abnormal signal that causes the robot R to perform the operation is output, and if there is no difference between the two posture data, the robot R is released from the standard posture and proceeds to the next work procedure.

An example of a case where the above-mentioned abnormality signal is output is when the grip part T' of the work hand T is partially deformed or chipped, as shown in FIGS. 5(a) and 5(b). This is the case.

"Effects of the Invention" As described above, the present invention includes a television camera attached to a robot manipulator, a reference posture control means for causing the robot manipulator to take a reference posture, and a robot manipulator that displays the appearance of the robot manipulator in the reference posture. A figure memory means for capturing an image with a television camera and storing the two-dimensional image pattern;
A diagnostic device for a robot manipulator, comprising a failure processing means that compares the memorized appearance of the robot manipulator with the currently imaged appearance of the robot manipulator, and performs failure processing when it is determined that the two are not the same. Therefore, the appearance of robots and manipulators, for example,
This is an extreme work robot that cannot stop work midway through, as it can accurately detect damage that could damage the appearance or fall off of parts, such as the wrists and hands, which are particularly susceptible to damage. It is suitable for many applications, and is particularly useful for diagnosing specific damage that does not cause electrical disconnection or an increase in load.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the signal flow of a diagnostic device according to an embodiment of the present invention, FIG. 2 is a flowchart showing the processing procedure in the diagnostic device, and FIG. 3 is a diagram of a robot in which the diagnostic device is commonly used. FIG. 4(a) is a perspective view showing an example of an undamaged robot; FIG. 4(b) is a plan view of the wrist in the standard posture shown in FIG. 4(a);
FIG. 4(a) is a perspective view of the wrist shown in FIG. 4(a) in a damaged state, and FIG. 4(b) is a view corresponding to FIG. 4(b) of the damaged wrist. (Explanation of symbols) 10... Robot control device 11... ITV camera 13... A/D converter 14... Image memory area R... Robot H.
・・Wrist T・Working hand S・・
・Swivel base.

Claims (1)

[Claims] (1) a. a television camera attached to the robot manipulator; b. a reference posture control means for causing the robot manipulator to assume a standard posture; and c. an image of the robot manipulator in the standard posture taken by the television camera. d. Compare the appearance of the robot/manipulator that was imaged and stored in the past by the above-mentioned image storage means with the appearance of the robot/manipulator that was imaged this time, and confirm that the two images are the same. A diagnostic device for a robot manipulator, comprising: a failure handling means that performs failure handling when it is determined that the robot/manipulator is not present.