JPH06344293A - Trouble diagnosing device for industrial robot - Google Patents

Abstract

PURPOSE:To provide a trouble diagnosing device for an industrial robot, which is constituted to automatically and rapidly diagnose the trouble cause of an amplifier incorporated in a robot body. CONSTITUTION:In a system wherein a robot body 2 having an amplifier 1 to store an operation content is connected to an external computer 10 through a controller 3, the external computer 10 is provided with a controller trouble diagnosing part 15 to detect the occurrence of the trouble of the amplifier 1; and an amplifier data acquiring part 12 to input data of the amplifier 1 during the occurrence of a trouble. Further, the external computer is provided with an analysis simulating part 13 to produce a simulation waveform by means of machine system and control system parameters; a waveform comparing part 14 to compare a simulation waveform and a trouble waveform with each other by means of a neural network; and a waveform cause diagnosing part 16 which looks up a built-in parameter cause relation table 17 when the simulation waveform coincides with the trouble waveform to diagnose a trouble cause.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fault diagnosing device for an industrial robot, and more particularly to a device capable of diagnosing the cause of a fault.

[0002]

2. Description of the Related Art Conventionally, an amplifier in an industrial robot (hereinafter simply referred to as a robot) having a servo amplifier (hereinafter simply referred to as an amplifier) capable of storing operation contents such as a position command, a speed command, a position feedback, a speed feedback, and a current value. The failure diagnosing device is constructed as shown in FIG. 5, for example. That is, the robot main body 2 incorporating the amplifier 1 is connected to the external computer 4 via the controller 3, and the computer 4 includes a failure diagnosis section 5 for diagnosing whether or not a failure has occurred in the amplifier 1, and an amplifier 1
And an amplifier data acquisition unit 6 for reading the state of When a failure occurs in the amplifier 1, the failure diagnosis section 5 of the computer 4 detects that the failure has occurred in the amplifier 1 by an abnormal signal from the controller 3, and the amplifier data acquisition section 6 receives the notification and the amplifier data acquisition section 6 receives the failure signal. Read state 1 from memory. Then, based on this data, the operator presumed the cause of the failure by trial and error.

[0003]

However, in such a conventional failure diagnosis device, since the operator eventually finds out the cause of the failure by trial and error, it generally takes time to repair the failure. . Moreover, since the experience and knowledge of the operator are largely responsible for inferring the cause, the failure recovery time greatly depends on the experience and knowledge of the operator.

The present invention has been made in view of the above problems of the prior art, and it is an object of the present invention to provide a failure diagnostic apparatus for an industrial robot capable of automatically diagnosing the cause of an amplifier failure in a short time. To aim.

[0005]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a robot main body having an amplifier for storing operation contents, a controller for controlling the robot main body, and a failure of the amplifier. An amplifier failure occurrence detecting means for detecting, an amplifier data input means for inputting data relating to the state of the amplifier, a simulation waveform generating means for generating a simulation waveform by a parameter related to the cause of the failure, the simulation waveform and the failure waveform. Waveform comparing means for comparing, data table storing means for storing a data table showing a correspondence relationship between the preset parameters and the cause of failure, and the data table when the simulation waveform and the failure waveform match. Failure cause inference that looks up and infers the cause of failure And having a means.

[0006]

In the present invention thus constituted, when the occurrence of an amplifier failure is detected by the amplifier failure occurrence detection means, the amplifier data input means inputs data relating to the state of the amplifier at the time of occurrence of failure, The simulation waveform generation means generates a simulation waveform from the parameters, and the waveform comparison means compares the simulation waveform and the failure waveform to determine whether they are the same. If they are not the same, the simulation waveform generation means changes the parameters so that the simulation waveform is the same as the failure waveform. If the simulation waveform and the failure waveform match, the failure cause inferring means looks up the data table stored in the data table storage means to infer the failure cause.

[0007]

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 schematic configuration diagram of a failure diagnosis device for an industrial robot according to this embodiment, FIG. 2 is a diagram showing an example of a parameter / cause relation table, FIG. 3 is a flowchart showing a processing procedure of this embodiment, and FIG. FIG. 3 is a block diagram showing an example of a configuration of a servo mechanism of a mobile robot. In addition, in FIG.
The same parts as those in FIG. 5 are designated by the same reference numerals.

In the failure diagnosis apparatus shown in FIG. 1, the robot body 2 incorporating an amplifier 1 (servo amplifier) for storing operation contents such as a position command, a speed command, a position feedback, a speed feedback, and a current value, as in the conventional case. The external computer 1 via the controller 3 which controls this
It is connected to 0.

The computer 10 is associated with a failure diagnosis section 11 for diagnosing the presence or absence of a failure of the amplifier 1, an amplifier data acquisition section 12 as an amplifier data input means for reading data regarding the state of the amplifier 1, and a failure cause. The simulation simulation unit 13 as a simulation waveform generation unit that generates a simulation waveform based on the parameters of the mechanical system and the control system, and the simulation waveform generated by the analysis simulation unit 13 and the amplifier data acquisition unit 12 are acquired. Further, it has a waveform comparing section 14 as a waveform comparing means for comparing a fault waveform such as a speed command or a current value when a fault occurs using a so-called neural network. And
The failure diagnosing unit 11 further includes a controller failure diagnosing unit 15 as an amplifier failure occurrence detecting unit that detects occurrence of a failure of the amplifier 1, and a failure cause inferring unit that looks up a data table described later to infer the cause of the failure. The waveform cause diagnosis unit 16 of FIG. The controller failure diagnosis unit 15 is the failure diagnosis unit 5 in the conventional system.
(See FIG. 5). Further, the waveform cause diagnosis unit 16 is provided with a parameter / cause relation table 17 as a data table storage means in which the parameters and the cause of failure are associated with each other and the corresponding relationship between them is set. The parameter / cause relation table 17 is appropriately set in advance based on experiments.

An example of the parameter / cause relation table 17 is shown in FIG. Here, for example, the seizure of the motor and the mechanical interference are taken as examples of the cause of the failure, and this is associated with the values of various parameters.
As will be described later, the cause of the failure of the amplifier 1 is diagnosed by looking up this table 17. In addition, various parameters (1 / R, Jl, J
m, Ke, etc.) correspond to the symbols appearing in the block diagram shown in FIG. The block diagram of FIG. 4 is a configuration example of the servo mechanism of the robot, which is used by the analysis simulation unit 13. In the figure, for example, "1 / R" is winding resistance, "Jl" is load inertia, "Jm" is rotor inertia, "Ke" is counter electromotive force coefficient, and "Kp" is
"i" is position integral gain, "Kpp" is position proportional gain,
"Kv" is a speed gain, "Kω" is a speed feedback coefficient, "Kt" is a torque constant, "D + sJl" is resistance + load inertia, and "1 / s" is an integral.

The present apparatus thus constructed operates according to the flowchart of FIG. First, when a failure occurs in the amplifier 1, the computer 10 detects that the failure has occurred in the amplifier 1 in the controller failure diagnosis unit 15 of the failure diagnosis unit 11 based on the abnormal signal from the controller 3 (S1). In response, the amplifier data acquisition unit 12
Captures data relating to the state of the amplifier 1 at the time of failure (S2).

Then, in the analysis simulation section 13, a reference simulation waveform is generated in advance by a characteristic parameter (see FIG. 4) of the mechanical system / control system, and then the waveform comparison section 14 compares the simulation waveform and the failure waveform. A neural network is used for comparison (S3), and it is determined whether the two are the same (S3).
4). If the result of this determination is that they are the same, the process immediately proceeds to step 6, but if they are not the same, the analysis simulation unit 13 selects the simulation waveform closest to the failure waveform as a result of the comparison in step 3, and selects the simulation waveform of the reference simulation waveform. By finely adjusting the parameters, the parameters are changed so that the waveform becomes the same as the fault waveform (S
5).

Then, the waveform cause diagnosis section 16 diagnoses the cause of the failure by looking up the built-in parameter / cause relation table 17 based on the parameter information when the failure waveform and the simulation waveform are the same ( S6). For example, various parameters that give the same simulation waveform as the fault waveform at the time of motor burn-in 1 /
The values of R, Jl, Jm, Ke, etc. are 5 or less and 100, respectively.
If the number is 2 or less, 1000 or more, it is diagnosed that the cause of the failure is motor burn-in by referring to the table in FIG.

Therefore, according to this embodiment, the amplifier 1
The cause of the failure can be automatically diagnosed in a short time, and the failure repair time can be greatly shortened.

[0015]

As described above, according to the present invention, the cause of the failure of the amplifier can be automatically diagnosed in a short time, so that the failure repair time can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a fault diagnosis device for an industrial robot according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a parameter / cause relation table according to the present embodiment.

FIG. 3 is a flowchart showing a processing procedure of this embodiment.

FIG. 4 is a block diagram showing an example of a configuration of a servo mechanism of an industrial robot.

FIG. 5 is a schematic configuration diagram of a conventional fault diagnosis device for an industrial robot.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Amplifier 2 ... Robot main body 3 ... Controller 10 ... Computer 11 ... Failure diagnosis part 12 ... Amplifier data acquisition part (amplifier data input means) 13 ... Analysis simulation part (simulation waveform generation means) 14 ... Waveform comparison part (waveform comparison 15) Controller failure diagnosis section (amplifier failure occurrence detection section) 16 ... Waveform cause diagnosis section (fault cause inference section) 17 ... Parameter / cause relation table (data table storage section)

Claims (1)

[Claims] 1. A robot main body provided with an amplifier for storing operation contents, a controller for controlling the robot main body, an amplifier failure occurrence detecting means for detecting occurrence of a failure of the amplifier, and data relating to the status of the amplifier. Amplifier data input means for inputting, simulation waveform generating means for generating a simulation waveform by parameters related to the cause of failure, waveform comparing means for comparing the simulation waveform and the failure waveform, the preset parameter and cause of failure A data table storage means for storing a data table showing a correspondence relationship between the simulation waveform and the failure waveform, and a failure cause inference means for inferring a failure cause by looking up the data table. An industrial robot characterized by having Of the failure diagnosis device.