WO2006045480A1

WO2006045480A1 - Method and device for evaluating machine states in step chains

Info

Publication number: WO2006045480A1
Application number: PCT/EP2005/011178
Authority: WO
Inventors: Michael Hulsch; Jürgen Mothsche; Simon Rützler
Original assignee: Bosch Rexroth Ag
Priority date: 2004-10-27
Filing date: 2005-10-18
Publication date: 2006-05-04
Also published as: DE102004052343A1

Abstract

The invention relates to a method for carrying out step chains and a criteria analysis of errors occurring in a programmable control system for a machine control system, machine steps in the step chain being additionally recorded and continuously monitored. The invention also relates to a device for carrying out step chains and a criteria analysis of errors occurring in a programmable control system for a machine control system, said device being provided with inputs for detecting machine states. This enables the diagnosis and operating behaviour programming of an SPS and an automatic consideration of the operating state of the control system to be simplified.

Description

Method and device for evaluating machine diameters in step sequences

State of the art

The invention relates to a method for performing step sequences and a criteria analysis of occurred errors in a programmable controller for a machine control.

The invention further relates to an apparatus for performing step sequences and criteria analysis of occurred errors in a programmable controller for a machine control.

Numerous industrial processes are controlled in programmable controllers by means of so-called step sequences, as described for example in DE 4134811 A1. In these methods signals to be output to devices and signals generated by devices are each assigned to functional elements. The functional elements interact in the context of steps which form the step sequences. The sequence of steps are associated with the instructions to be executed by the individual devices during the process. The smallest units of the step sequences are actions or the steps which, in the automatic mode of a process without manual intervention, only function in dependence on the input conditions (transition conditions). In general, a so-called manual operation is still provided, in which the transition from a step to a subsequent step is only performed when additionally a touch button is pressed. This is used to set up the machine and error analysis. Examples of such controllers with sequencers are Programmable Logic Controllers (PLC) from SIEMENS (eg STEP 7), BOSCH REKROTH (Madap or IndraStep) or 3S (CoDeSys).

The disadvantage is that in conventional sequencers diagnostic functions can be achieved only with great effort. For example, conditions for the machine states must be programmed in several places, some of which are also negated. For maintenance and enhancements, changes often have to be made in several places. This can cause errors in the program, which must be searched with great effort. If different systems are linked, it can happen that similar errors can not be treated with a uniform diagnosis since they are issued by different message systems. Furthermore, it may happen that auxiliary criteria are displayed in the criteria analysis, which are not linked to the actual cause of the error.

It is an object of the invention to provide a method for performing step sequences and criteria analysis of occurred faults in a programmable controller for a machine control, which simplifies maintenance and troubleshooting. It is a further object of the invention to provide a device for this purpose.

Advantages of the invention

The object relating to the method is achieved by additionally recording and constantly monitoring machine states in the step sequence. This ensures that the error rate of program creation is reduced during expansion and maintenance. In a preferred embodiment, the machine states are fed to additional inputs of the sequencer. 'This allows permanent monitoring of machine conditions in all operating modes.

If the machine states are defined at a single point in the controller, the conditions for these machine states need only be programmed in one place, and a consistent diagnosis of all the step messages is enabled.

Quick troubleshooting is made possible by the criteria analysis in an error case lists all relevant faulty machine states.

If the criteria analysis lists the relevant faulty machine states for a diagnostic message, the diagnostic messages are particularly meaningful.

Safe operation of the machine control system and rapid error analysis are achieved by the fact that the criteria analysis supplies the relevant faulty machine states for an automatic error detection and an error message is generated, whereby the step sequence can be stopped. If the machine states lead to diagnostic messages or a status change, depending on the status of the sequencer, an error analysis is simplified, as only messages relevant to the current status are generated.

If the machine status is missing in a state when diagnostic messages or a status change occur, an error analysis can be performed when the machine is stopped due to the messages.

In a preferred embodiment, in a state automatic missing machine states lead to diagnostic messages or a state change. This ensures that when an error occurs during operation the - A -

Machine can be stopped and the error due to the diagnostic message can be detected.

An analysis of the program sequence of the sequencer is made possible by manually missing machine states in a state leading to diagnostic messages or a state change.

An analysis of the first start of the program for the machine control is made possible if, in the state Automatic start conditions and / or when leaving an Init step monitors a home position and lead to a diagnostic messages or a state change in the absence.

The object relating to the device is achieved by providing inputs for detecting machine conditions. As a result, they are only recorded in one place. Changes and extensions of the detection have the same effect on all parts of the device; Errors are avoided.

If the management of the sequencers is structured in the form of a state machine, it is possible to achieve a clear representation of the device and its behavior, and deviations from the correct function can be quickly analyzed and eliminated.

An error analysis and correction is simplified when the controller for the stop mode is designed so that in a missing machine state sin machine state error reported and start conditions are displayed and / or on successful query of the state manual a setup diagnosis is reported.

Ξ A faulty start of the machine is avoided if the control for the operating mode Auto is designed so that in case of a missing start condition Machine status error is reported and / or when leaving the init step, a missing basic position is monitored and / or transferred to the basic position branch if the basic position is missing.

If the control for the manual operating mode is designed such that a machine state error is reported in the event of a missing machine state, an error analysis and rectification can be carried out in the individual step mode.

drawing

The invention will be explained in more detail below with reference to an embodiment shown in FIGS. Show it:

Figure 1 is a schematic flow chart in which the starting conditions and the basic position are evaluated in the stop state;

Figure 2 is a schematic flowchart in the state of car;

Figure 3 is a schematic flowchart in the hand state;

Figure 4 is a schematic representation of the management of the sequencers in the form of a state machine

Description of the embodiments

1 shows an exemplary embodiment of the invention for the "stop" state, in which starting conditions and the basic position are evaluated, in which case the term machine states describes the starting conditions and the basic position. Depending on the state, the machine states are evaluated and lead to corresponding diagnostic messages or to a state change. Depending on the operating mode, missing machine states are issued as different messages. When leaving the Stop state, missing machine states are evaluated and possibly lead to an error message and the transition to the error state.

In the concrete example, starting from a state Start 10, first a machine state is read in. 20. The query "Start?" 1O1 follows. If this query is negated, a query "Missing machine state?" Follows. 102. When Ver¬ connection is followed by a return to the state start 10. If a missing Maschinen¬ state detected, followed by a query "hand?" 103. In the mode of operation is followed by action as a process report Einrichtdiagnose 50. Otherwise follows a process Start¬ Report requirements 40. Can the query "Start?" 101 is answered in the affirmative, is another query "missing machine state?" 102. If so, then an action report machine state error 30 occurs, after which an error 120 state is reached. 1.O2 is not the case, a further query "manual?" 103 is made, with which a distinction can then be made between a state Auto 130 or a state Manual 140. With this procedure, missing machine states can already be detected and analyzed in the Stop state.

Figure 2 shows a schematic flow chart in the state Auto 130. In addition to the conventional error detections timeout and monitor error here are the Maschinenenzμstände evaluated and possibly lead to an error message and the transition to the state Error 120. The basic condition is only when leaving the Init step evaluated. Switching to the basic position branch is possible in this case despite missing basic condition. The schematic flowchart in the state Auto 130 initially provides a query "Stop?" 111. If this query is affirmative, the transition to the state Stop 150 takes place. If the answer is negative, a query "Timeout?" 112. If yes, then a step 70 will report a time error, after which the error 120 state will be taken. Otherwise, a query follows "Monitor Error?" 113. If there is a monitor error, a Report Monitor Error 60 occurs, which in turn returns to Error 120. If there is no monitor error, the Read Machine Status 20 action follows, followed by a poll "Missing start requirement?" 114. If this query is answered in the affirmative, a jump is made to the action step Report Machine State Error 30, after which the state Error 120 is again reached.

If there is no missing start condition, a query "Leave init step?" 115. If this query is denied, there is a return to the state Auto 130th If this is true, then a query "missing basic position?" 116. If this query is rejected, the system returns to the state Auto 130. If this is the case, a query "Basic setting branch?" 117 is made. The basic branch can therefore also be reached if the basic setting is missing. If this is not true, the state error 120 is reached, wherein previously in one action step the machine state error 30 is reported.

FIG. 3 schematically shows a flowchart for the state of the hand 140. In addition to the conventional error detection of the monitor error, the machine states are evaluated here and possibly lead to an error message and the transition to the error 120 state.

Starting from the state of hand 140, the query is first made, - "Stop?" 111. If this applies, the transition to the state Stop 150 takes place immediately. If this is not true, a query "Monitor error?" 113 queried whether a monitor error is present. If this is the case, the state error 120 is activated after the Action Step Report Monitor Error 60 has been executed. If there is no monitor error, the machine state parameters are read in in step Read Machine State. If these are missing, which is detected in a subsequent query "missing machine state?" 102, the state error 120 is also reached after a corresponding display is made in the step Report machine state error 30.

FIG. 4 shows the management of the operating modes of the step sequence in the form of a state machine. The state machine has the states Auto 130, Error 120, Stop 150 and Hand 140.

From the state Stop 150, the state Auto 130, as shown in FIG. 1, is reached via Start 10 with a negative query "Hand?" 103. Is the query "Hand?" 103 affirmatively, the state of the hand 140 is reached by the state 150. Both the state Auto 130 and 140, the state stop 150 is reached on the successful query stop 111. If a machine state error 30 is reported in the state Stop 150, the state Error12O is transited.

If a machine state error 30 is reported in state Auto 130, the state Error 120 is transited. This is also done when reporting a monitor error 60 or a time error 70th

From the state of hand 140 is transferred to the state error 120 when reporting a monitor error 60 or a missing machine state 30.

From state error 120, the transition clear error condition 31 leads to state stop 150.

In the shown /! For example, the sequencer receives additional inputs on which the conditions for the machine states, eg start prerequisite, basic position, etc., can be created. These conditions evaluate the sequence of steps automatically, so they do not need to be programmed elsewhere. The reaction to the machine states depends on the operating mode and the active steps of the sequencer.

There are basically two types of evaluation:

1. Diagnostic messages and

2. automatic error detection.

For diagnostic messages, missing conditions are provided as message of the sequencer. For example, a missing basic position in the automatic mode (state Auto 130) is reported as a message of the type Starvoräussetzung. In manual mode (manual mode 140), on the other hand, a missing basic position is mixed as a message of the type setup diagnostics.

For these messages, a criteria analysis is also available, so that the machine operator can directly recognize which condition, eg. B. for Grund¬ position is still missing.

With automatic error detection, the sequencer automatically detects missing conditions. The sequencer, and thus also the machine, is stopped and an error message is triggered. The criteria analysis is again available for this error message so that the machine operator can immediately know the cause of the error. An automatic error detection can be designed, for example, such that when leaving the init step, the basic position is monitored. If the machine is not in the basic position, the sequencer goes into the error 120 state. After leaving the init step, the basic position is no longer checked and no longer results in an error. The start requirements are constantly monitored during operation and, in the absence of conditions, lead directly to the step sequence changing to the error 120 state. Such a method can generally find use in automation and plant automation, for example in packaging and welding technology, as well as in general in drive and control technology.

Claims

claims

1-. Method for carrying out step sequences and a criteria analysis of errors that have occurred in a programmable controller for a machine control system, characterized in that machine states are additionally recorded and continuously monitored in the step sequence.

2. The method according to claim 1, characterized in that the machine states are fed to additional inputs of the step sequence.

3. The method according to claim 1 or 2, characterized in that the machine states are defined at a single point of the controller.

4. The method according to any one of claims 1 to 3, characterized in that the criteria analysis lists all relevant faulty machine states in an error case.

5. The method according to any one of claims 1 to 4, characterized in that the criteria analysis lists the relevant faulty machine states for a diagnostic message.

6. The method according to any one of claims 1 to 5, characterized in that for an automatic error detection, the criteria analysis provides the relevant faulty machine states and an error message is generated.

7. The method according to any one of claims 1 to 6, characterized in that the machine states, depending on the state of the sequencer, lead to diagnostic messages or a state change.

8. The method according to any one of claims 1 to 7, characterized in that in a state stop missing machine states lead to diagnostic messages or a state change.

9. The method according to any one of claims 1 to 7, characterized in that in a state automatic missing machine states lead to diagnostic messages or a state change.

10. The method according to any one of claims 1 to 7, characterized in that in a state hand missing machine conditions lead to diagnostic messages or a state change.

11.A method according to any one of claims 1 to 7 and 9, characterized in that in the state automatic start conditions and / or when leaving an init step monitored a basic position and lead to the absence of diagnostic messages or a state change.

12. An apparatus for performing step sequences and a criteria analysis of errors occurred in a programmable controller for a machine control, characterized in that inputs are provided for detecting machine conditions.

13. The apparatus according to claim 12, characterized in that the management of the step sequences is constructed in the form of a state machine.

14. Device according to one of claims 12 or 13, characterized in that the control for the stop mode is designed so that in a missing machine state reported a machine state error and start conditions are displayed and / or successful completion of the state hand a setup diagnosis is reported ,

15. The device according to any one of claims 12 or 13, characterized in that the control for the operating mode Auto is designed so that at a missing start requirement, a machine state error is reported and / or monitors a missing basic position when leaving the init step and / or is transferred in the absence of basic position in the basic position branch.

16. Device according to one of claims 12 or 13, characterized in that the control for the operating mode hand is designed so that when a machine condition is missing, a machine condition error is reported.

LIST OF REFERENCES

10 start

20 Read machine status

30 Report machine condition error

31 Delete error condition

40 Report start requirement

50 Report setup diagnostics

30 Report a monitor error

70 Report a time error

101 Query "Start?"

102 Query "Missing machine state?"

103 Query "Hand?"

111 Query "Stop?" 12 Query "Timeout?" 13 Query "Monitor error?" 14 Query "missing start requirement?" 15 Query "Exit init step?" 16 Query "missing basic setting?" 17 Query "Startup branch?"

20 State Error 30 State Auto 40 State Manual 50 State Stop