Method and device for automatically generating a production machine or machine tool control program which is solely designed for diagnostic purposes

Abstract

A method and a device operating according to the method automatically generate a control program designed for diagnostic purposes of a production machine or machine tool. The control program is generated using freely selectable parameters and/or machine-specific parameters by an algorithm which defines a movement profile. The movement profile incorporates at least one test run for at least one axis of the respective production machine or machine tool, wherein the at least one test run produces an axis excitation which is suitable for determining at least one mechatronic characteristic variable of the respective axis.

Claims

1. A method for automatically generating a control program, which is designed for diagnostic purposes, for a production machine or machine tool, the method comprising: generating the control program with an algorithm which comprises freely selectable parameters or machine-specific parameters, or both; defining with the automatically generated control program a movement profile for at least one test run for at least one axis of the respective production machine or machine tool: producing with the at least one test run an axis excitation of the at least one axis suitable for determining at least one mechatronic characteristic variable of the at least one axis, and determining a number of acceleration jumps along a predetermined limited travel distance for the at least one test run; wherein the at least one test run comprises the determined number of acceleration jumps and a constant speed travel before and after each acceleration jump.

2. The method of claim 1, wherein the at least one test run comprises travel movements having a maximum machine-specific speed or a maximum machine-specific acceleration.

3. The method of claim 1, wherein the movement profile comprises a plurality of test runs for determining different mechatronic characteristic variables.

4. The method of claim 3, wherein the movement profile comprises different sections having each at least one test run for determining a respective mechatronic characteristic variable.

5. A processing unit designed to automatically generate a control program for diagnostic purposes of a production machine or machine tool, comprising: a microprocessor, and a memory, wherein a computer program, when loaded into the memory and executed by the microprocessor, causes the processing unit to receive freely selectable parameters or machine-specific parameters, or both, and generate therefrom the control program which defines a movement profile with at least one test run for at least one axis of the respective production machine or machine tool; produces with the at least one test run an axis excitation of the at least one axis suitable for determining at least one mechatronic characteristic variable of the at least one axis, and determines a number of acceleration jumps along a predetermined limited travel distance for the at least one test run; wherein the at least one test run comprises the determined number of acceleration jumps and a constant speed travel before and after each acceleration jump.

6. A computer program embedded in a non-transitory storage medium and having program code, which when loaded into a memory of a processing unit of a production machine or machine tool and executed by a microprocessor of the processing unit, causes the processing unit to receive freely selectable parameters or machine-specific parameters, or both, and generate therefrom the control program which defines a movement profile with at least one test run for at least one axis of the respective production machine or machine tool; produces with the at least one test run an axis excitation of the at least one axis suitable for determining at least one mechatronic characteristic variable of the at least one axis, and determines a number of acceleration jumps along a predetermined limited travel distance for the at least one test run; wherein the at least one test run comprises the determined number of acceleration jumps and a constant speed travel before and after each acceleration jump.

7. A computer program product comprising program code embedded in a non-transitory storage medium, which program code, when loaded into a memory of a processing unit of a production machine or machine tool and executed by a microprocessor of the processing unit, causes the processing unit to receive freely selectable parameters or machine-specific parameters, or both, and generate therefrom the control program which defines a movement profile with at least one test run for at least one axis of the respective production machine or machine tool; produces with the at least one test run an axis excitation of the at least one axis suitable for determining at least one mechatronic characteristic variable of the at least one axis, and determines a number of acceleration jumps along a predetermined limited travel distance for the at least one test run; wherein the at least one test run comprises the determined number of acceleration jumps and a constant speed travel before and after each acceleration jump.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) In the drawings:

(2) FIG. 1 shows a movement profile of a machine axis of a production machine or machine tool,

(3) FIG. 2 shows a schematically simplified overview of the approach proposed here,

(4) FIG. 3 shows an acceleration jump, and

(5) FIG. 4 shows a movement curve with acceleration jumps and constant speed runs.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(6) The illustration in FIG. 1 shows by way of example a movement profile 10 of an axis of, in principle, any production machine or machine tool not shown itself and known per se, in particular, of such a machine in the form of a machine tool, an industrial robot and the like (as aforementioned). The movement profile 10 comprises individual test runs 12 for the purpose of determining or evaluating mechatronic characteristic variables of the respective axis of the production machine or machine tool.

(7) Such movement profiles 10 are currently being created manually if necessary. Individual sections of the movement profile 10, with the respective test runs 12 there, form the basis for determining different mechatronic characteristic variables of the axis or axes moved during the test run 12. In the example shown in FIG. 1, the movement profile 10 comprises a plurality of sections (I, II, III, IV), wherein in each section a test run 12 for determining a mechatronic characteristic variable or essentially a mechatronic characteristic variable takes place. The illustration of the test runs 12 shown is only to be understood as an example and in this respect the illustration in each section only shows one “outward journey” (plus run) and one “return journey” (minus run) of the respective feed axis.

(8) In the situation shown in FIG. 1, the movement profile 10 comprises four sections by way of example. In principle, a movement profile 10 intended for determining mechatronic characteristic variables may comprise more or fewer than four sections. The movement profile 10 preferably comprises one section for each mechatronic characteristic variable to be determined, namely one section in which, by means of the test run 12 defined there, an excitation of the respective feed axis which is particularly favorable for determining the respective mechatronic characteristic variable takes place.

(9) In practice, the design of such test runs 12 is dependent on the mechatronic characteristic variables to be determined and individual axis properties. This relationship is shown schematically simplified in FIG. 2.

(10) The mechatronic characteristic variables to be determined are, in particular, the characteristic variable “friction”, the characteristic variable “rigidity” and the characteristic variable “slack”. An optional further mechatronic characteristic variable describes a fault in a ball screw drive (KGT).

(11) The illustration in FIG. 2 shows freely selectable parameters 20 and machine-specific parameters 21 as input data for an algorithm 22 for generating a control program 23 for a respective machine, in particular, for generating a control program 23 in the form of an NC program.

(12) In order to execute the algorithm 22 and to generate the control program 23 in the context of the execution of the algorithm 22, a processing unit 24 is provided. In a manner in principle known per se, this comprises a microprocessor 25 or the like and a memory 26 into which the algorithm 22 can be loaded in the form of or as part of a computer program 22 and is loaded during operation of the processing unit 24. The processing unit 24 may be part of the machine control of the respective machine, such that the processing unit 24 uses a microprocessor or the like of the machine control for the execution of the algorithm 22 and a part of a memory of the machine control of the production machine or machine tool as the memory. The processing unit 24 may also be independent of the respective machine and its machine control, such that by means of the processing unit 24, a control program 23 is occasionally generated or modified for the respective machine and this is loaded into the memory of the machine control of the machine in a manner which is in principle known per se.

(13) The freely selectable parameters 20 include, for example, a duration of a run at constant speed (constant speed run) symbolically denoted by t.sub.vrun. The duration is given in seconds, for example. Furthermore, in the illustration in FIG. 2 a duration of a run at constant acceleration (constant acceleration run) symbolically denoted by t.sub.arun, a speed of a constant speed run symbolically denoted by v.sub.vrun and an acceleration of a constant acceleration run symbolically denoted by a.sub.arun are shown as freely selectable parameters 20. The duration (t.sub.vrun, t.sub.arun) is given in seconds. The speed (v.sub.vrun) is given in m/s (meters per second). The acceleration (a.sub.arun) is given in m/s.sup.2. The freely selectable and thus predeterminable parameters 20 also include an initial speed V.sub.0 given in m/s (meters per second) at the time t=0. The freely selectable parameters 20 are determined, for example, by specialists, in particular by specialists of a manufacturer of a respective machine or machine axis.

(14) Optionally, the machine-specific parameters 21 are automatically read from a machine control (not shown) of the respective machine (production machine or machine tool). The machine-specific parameters 21 include, in particular, the travel limits of the respective machine axis symbolically denoted by x.sub.min, x.sub.max: maximum values with regard to speed, acceleration and jerk (v.sub.max, a.sub.max, j.sub.max), an active zero offset x.sub.0 and a respective active tool W.

(15) In brief, a control program 23 for a respective machine is automatically generated by specifying at least one test run 12 based on the freely selectable parameters 20 and the machine-specific parameters 21 for each mechatronic characteristic variable to be determined, leading to an excitation of the respective machine axis which is particularly favorable for determining the respective mechatronic characteristic variable. In the automatically generated control program 23, a test run 12 for determining the mechatronic characteristic variable “rigidity” (test run 12 for rigidity determination) is defined, inter alia, for example by a maximum acceleration that occurs during the test run 12. Furthermore, such a test run 12 is defined in the automatically generated control program 23 by the path length to be travelled. These parameters of a test run 12 are the result of algebraic arithmetic operations which are part of the algorithm 22. By means of the algorithm 22, the aforementioned maximum acceleration during the test run 12 for rigidity determination and the path length to be travelled are thus determined on the basis of the freely selectable parameters 20 and/or the machine-specific parameters 21. Furthermore, the determined results are converted into program code instructions of the automatically generated control program 23 by means of the algorithm 22 so that when the control program 23 is executed on a machine suitable for this purpose, a test run 12 with the determined path length and the determined acceleration results. For other mechatronic characteristic variables this applies accordingly, for example, for determining a maximum path length of a test run 12 for friction determination or determination of a maximum possible number of acceleration jumps of a test run 12 for rigidity determination.

(16) By way of example, the determination of a maximum possible number of acceleration jumps during a test run 12 is described hereinafter with reference to the illustrations in FIG. 3 and FIG. 4.

(17) For an individual acceleration jump—reference number 30—, as shown by way of example in FIG. 3, and from short, constant returns with the maximum possible jerk J (J=j.sub.max) of the respective axis (in m/s.sup.3) and an acceleration phase of the length T (T=t.sub.arun), the path X.sub.jump is produced:
X.sub.jump=((A+JT).Math.(2A.sup.2+JAT+2JV.sub.0))/J.sup.2

(18) In addition to the acceleration jump 30, the illustration in FIG. 3 shows—in each case plotted over the time t—the underlying jerk profile 32 as well as a resulting speed profile 34 and the movement curve 36 of an individual acceleration jump.

(19) Overall, however, a predetermined or predeterminable number N of acceleration jumps of the type shown in FIG. 3 are to be moved one after the other, wherein before and after each acceleration jump a constant speed run, in particular, a slow constant speed run, takes place for the purpose of obtaining the prestressing of the drive train. A resulting movement curve 40 (FIG. 4) therefore comprises N acceleration jumps and N+1 constant speed runs in total.

(20) With the movement curve 40, the illustration in FIG. 4 shows an enlarged section from the movement profile 10 according to FIG. 1, the time being plotted on the abscissa and the path in millimeters on the ordinate. In the further illustrations in FIG. 4, the speed V—reference number 42—in mm/s and the acceleration A—reference number 44—in mm/s.sup.2 are shown below the movement curve 40 and above the same time base.

(21) The total displacement X.sub.total path for N acceleration jumps is:

(22) $\begin{array}{c}{X}_{\mathrm{total}\mathrm{path}}=\left(t_{\mathrm{vrun}}.Math.v_{\mathrm{vrun}}.Math.\left(N+1\right)\right)+N.Math.X_{\mathrm{jump}}\\ =\left(t_{\mathrm{vrun}}.Math.v_{\mathrm{vrun}}.Math.\left(N+1\right)\right)+N\left(\left(A+\mathrm{JT}\right).Math.\left(2A^2+\mathrm{JAT}+2{\mathrm{JV}}_0\right)\right)/J^2\end{array}$

(23) Solved for N, a maximum number N.sub.max of possible acceleration jumps for a limited travel distance X.sub.max of a specific machine axis is obtained:
N.sub.max=(X.sub.max−t.sub.vrun.Math.v.sub.vrun)/(t.sub.vrun.Math.v.sub.vrun+((A+JT).Math.(2A.sup.2+JAT+2JV.sub.0))/J.sup.2)

(24) If N.sub.max is not an integer, rounding off takes place.

(25) The calculations described as well as the final determination of the maximum possible number N.sub.max of possible acceleration jumps within the given travel distance X.sub.max are executed according to the algorithm 22 by means of a processing unit 24 executing the algorithm 22 and the processing unit 24 is designed and set up by means of the algorithm 22/computer program 22 loaded into the memory 26 to carry out these calculations and determinations.

(26) With the data thus calculated by means of the algorithm 22—likewise by means of the algorithm 22—a control program 23 for a machine axis of a production machine and/or machine tool can be generated. In the case of a production or machine tool having a plurality of machine axes, the algorithm 22 can of course be performed for each individual machine axis or individual machine axes or a group of machine axes.

(27) When executing a control program 23 automatically generated by means of the algorithm 22 on a respective machine (production machine or machine tool), measured values are recorded by means of a sensor system in principle known per se and/or by reading out characteristic values, for example current and/or voltage, from a drive control of the machine or a machine axis on the basis of which the determination of at least one mechatronic characteristic variable is possible.

(28) Although the invention has been illustrated and described in detail by the exemplary embodiment, the invention is not limited by the disclosed examples and other variations can be derived therefrom by a person skilled hi the art without departing from the scope of protection of the invention.

(29) Prominent individual aspects of the description submitted here can thus be summarized briefly as follows: a method and a device which operates according to the method for automatically generating a control program 23 for a production machine or machine tool which is designed for diagnostic purposes is disclosed. The control program 23 is generated by means of an algorithm 22 using freely selectable parameters 20 and/or machine-specific parameters 21. The resulting, automatically generated control program 23 defines a movement profile 10, namely a movement profile 10 with at least one test run 12, for at least one axis of the respective production machine or machine tool. The at least one test run 12 produces an excitation of this axis which is suitable for determining at least one mechatronic characteristic variable of the respective axis. The automatically generated control program 23 is thus the basis for a mechatronic machine analysis which is practically not able to be performed, at least not able to be performed in an economically reasonable manner, without such automatically generated control programs 23 and the mechatronic characteristic variables obtainable thereby.