DE102008043100A1 - Fault diagnosing device for optimizing maintenance procedures in system, comprises logic unit, computation unit and storage unit for storing diagnosis regulations, where fault condition indicates fault - Google Patents

Abstract

The fault diagnosing device (2) comprises a logic unit (2B), a computation unit (2C) and a storage unit (2A) for storing diagnosis regulations. The computation unit is provided for computing a probability of occurrence for each cause of fault hypothesis of the logical diagnosis results. A fault condition indicates the fault which is formed by a logical operation of the causes. Independent claims are included for the following: (1) a method for optimizing maintenance procedures in an object of a system; (2) a computer program with a data medium for executing a maintenance procedures optimizing method; and (3) a maintenance device for maintenance of a flying object.

Description

The The invention relates to a fault diagnosis device and a method to optimize maintenance activities in technical systems, such as vehicles, ships, machinery, Computers, robots, vending machines, industrial equipment and in particular Aircraft. The invention is described below using the example of an aircraft explained.

One Flying object, such as an airplane or a helicopter exists from a variety of components or components, some of them networked with each other. These aircraft components may for example, actuators, sensors, data or power lines, Data transmission units and computing devices, such as computers or servers, act. These structural components of the aircraft are partially interchangeable and are referred to as Line Replaceable Units (LRU) components. Such LRU units are over Data lines or buses connected to data processing units or arithmetic units. A flying object, for example a passenger plane, can be a Have a variety of different aircraft systems. Examples of such flight systems are the chassis, the air conditioning or a pressure control. each Flight system may have one or more control computer. such Control computers are also called CPIOM units (Central Processing Input Output Module). For security reasons in many aircraft systems several control computers provided so the aircraft system has some redundancy over failures. On the control computers the Various aircraft systems are programs for carrying out the control operations executed.

The different components of the various aircraft systems can during flight operations Have errors. An error is a deviation from one Normal function of the respective aircraft system component. An error occurs when the behavior of a function of a given Behavior deviates. This is usually by comparing signal measurements with thresholds or detected by an error detection logic. The different aircraft system components can through monitoring programs or be monitored by electronic logic circuits.

kick an error event during of the flight operations, be first to guarantee the safety of the flying object or the aircraft measures taken to restore the failed or faulty function, For example, by activating redundant components. Furthermore The pilot of the aircraft is dysfunctional, in particular in case of failure of a function by means of a flight warning system of the aircraft, warned especially in case of failure of critical functions, so the pilot takes the necessary measures to guarantee the safety of the aircraft. The occurrence of a Error event results about that in addition to conventional Systems for generating error messages via an on-board maintenance system of the aircraft in preparation for repair of faulty components or faulty devices are transmitted.

These conventional However, there are some disadvantages to this approach. The number of predefined Error messages are limited and incomplete. In contrast, can the number of possible Error events or error event combinations for all potential ones Causes of errors within an aircraft to be very high. By the high number of possible Error events increase the number of possible error event combinations exponential and thus also the number of necessary error messages. Because the predefined error messages and their link with the error events are predefined or written by a developer, There is a considerable programming and configuration effort. About that In addition, this conventional offers Procedure no flexibility during the term or the Flight operations.

It It is therefore an object of the present invention to provide a fault diagnosis device and a method for optimizing maintenance on a system create that allows it while The error occurring during operation is flexible for preparation and initiation of maintenance evaluate with little effort.

These The object is achieved by a Fault diagnosis device with the specified in claim 1 Characteristics solved.

• – einer Speichereinheit zum Speichern von Diagnoseregeln, die jeweils eine Fehlerbedingung, welche das Vorhandensein eines Fehlers angibt, und eine Fehlerschlussfolgerung aufweisen, welche durch logische Verknüpfungen von potenziellen Fehlerursachen des jeweiligen Fehlers gebildet wird;
• – einer Logikeinheit, die diejenigen gespeicherten Fehlerschlussfolgerungen deren zugehörige Fehlerbedingungen erfüllt sind, logisch verknüpft und auf Grundlage der verknüpften Fehlerschlussfolgerungen ein logisches Diagnoseergebnis ermittelt, das mindestens eine Fehlerursachenhypothese aufweist; und
• – mit einer Berechnungseinheit, die eine Auftrittswahrscheinlichkeit für jede Fehlerursachenhypothese des logischen Diagnoseergebnisses berechnet.

The invention provides a fault diagnosis device for optimizing maintenance measures in a technical system, for example an aircraft, with:

• A memory unit for storing diagnostic rules each having an error condition indicating the presence of an error and a fault conclusion formed by logically linking potential causes of failure of the respective error;
• A logical unit that logically matches those stored fault conclusions whose associated fault conditions and, based on the linked fault inference, determines a logical diagnostic result that has at least one fault cause hypo having; and
• With a calculation unit which calculates an occurrence probability for each cause of error hypothesis of the logical diagnosis result.

at an embodiment the fault diagnosis device according to the invention transmits the calculation unit the calculated occurrence probabilities of the error cause hypotheses of the logical diagnostic result via an interface to a Maintenance device.

at a possible embodiment the maintenance device has a maintenance unit which maintenance procedures, each predetermined to a fault cause hypothesis of the diagnosis result are, depending from the calculated occurrence probabilities of the fault cause hypotheses one after the other, until the error is corrected.

at an embodiment the fault diagnosis device according to the invention the calculation unit sorts the error cause hypotheses of the logical diagnostic result according to the calculated occurrence probabilities the root cause hypothesis.

at an embodiment the fault diagnosis device according to the invention is the fault diagnosis device in an object of the system, for example a flying object, provided.

at an embodiment the fault diagnosis device according to the invention have some or all of the flying object components of the flying object or of the aircraft on an integrated fault diagnosis device.

at a possible embodiment are the diagnostic devices of flying object components or of devices of the aircraft, which belong to the same aircraft system, interconnected.

at an embodiment the fault diagnosis device according to the invention transmits the fault diagnosis device the calculated occurrence probabilities of the fault cause hypotheses over a Radio interface in a flying operation of the flying object to the maintenance device, which is located at a destination airport of the flying object for maintenance measures prepare.

These embodiment offers the advantage that maintenance during flight operations the Flight object at the destination airport can be prepared purposefully so that the implementation of maintenance can be carried out quickly after landing of the aircraft or flying object. hereby is the necessary maintenance time of the flying object or the aircraft minimized, so especially during a stopover of the aircraft no delay occurs.

at a possible embodiment the fault diagnosis device according to the invention connected the logic unit the stored fault conclusions of the Diagnostic rules logical AND together.

at an embodiment the fault diagnosis device according to the invention Determines the logic unit using logical Boolean calculation rules based on the linked Fault conclusions of the diagnostic rules the logical diagnostic result automatically.

at an embodiment the fault diagnosis device according to the invention will be the fulfillment an error condition of a diagnostic rule by an error detector a flying object component detected within the flying object.

at an embodiment the fault diagnosis device according to the invention If a diagnostic rule consists of logical links of flying object components, that could have caused the error.

at an embodiment the fault diagnosis device according to the invention is for every fault cause in a hypothesis of the diagnosis at least one associated Maintenance procedure exists that includes multiple maintenance actions includes.

at an embodiment the fault diagnosis device according to the invention Maintenance procedures are performed by the maintenance unit in order the sorted occurrence probabilities of the associated error cause hypotheses executed.

at an embodiment the fault diagnosis device according to the invention each potential cause of failure has a flying object component and a functional state of this flying object component.

at an embodiment the fault diagnosis device according to the invention have the flying object components of the flying object actuators, sensors, Lines, data exchange units and data processing units on.

• – Bereitstellen von Diagnoseregeln, die jeweils eine Fehlerbedingung, welche das Vorhandensein eines Fehlers angibt, und eine Fehlerschlussfolgerung aufweisen, welche aus einer logischen Verknüpfung von potenziellen Fehlerursachen des Fehlers besteht;
• – logisches Verknüpfen von denjenigen Fehlerschlussfolgerungen deren zugehörige Fehlerbedingung erfüllt ist;
• – Ermitteln eines logischen Diagnoseergebnisses, welches mindestens eine Fehlerursachenhypothese aufweist, auf Basis der verknüpften Fehlerschlussfolgerungen;
• – Berechnen einer Auftrittswahrscheinlichkeit für jede Fehlerursachenhypothese des logischen Diagnoseergebnisses.

The invention further provides a method for optimizing maintenance measures for an object of a system, in particular a flying object, comprising the steps:

• Providing diagnostic rules each having an error condition indicating the presence of an error and a fault conclusion consisting of a logical association of potential causes of the error;
• - logical linking of those fault conclusions whose associated error condition is met;
• Determining a logical diagnostic result having at least one cause of error hypothesis based on the linked fault inferences;
• Calculate a probability of occurrence for each error cause hypothesis of the logical diagnosis result.

at an embodiment the method according to the invention the fault cause hypotheses are calculated according to the calculated Appearance probabilities sorted and the error cause hypotheses associated Maintenance procedures in the order of sorted fault cause hypotheses executed.

at an embodiment the method according to the invention is the presence of an error by an error detector while a flight operation of the flying object detected.

at an embodiment the method according to the invention the order of the sorted fault cause hypotheses becomes Detecting a fault at a destination airport of the flying object via a Radio interface for preparing appropriate maintenance procedures Posted.

• – Bereitstellen von Diagnoseregeln, die jeweils eine Fehlerbedingung, welche das Vorhandensein eines Fehlers angibt, und eine Fehlerschlussfolgerung aufweist, welche aus einer logischen Verknüpfung von potenziellen Fehlerursachen des Fehlers besteht;
• – logisches Verknüpfen von denjenigen Fehlerschlussfolgerungen deren zugehörige Fehlerbedingung erfüllt ist;
• – Ermitteln eines logischen Diagnoseergebnisses, welches mindestens eine Fehlerursachenhypothese aufweist, auf Basis der verknüpften Fehlerschlussfolgerungen;
• – Berechnen einer Auftrittswahrscheinlichkeit für jede Fehlerursachenhypothese des logischen Diagnoseergebnisses.

The invention further provides a computer program for carrying out a method for optimizing maintenance measures in a flying object with the following steps:

• Providing diagnostic rules each having an error condition indicating the presence of an error and an error conclusion consisting of a logical association of potential causes of the error;
• - logical linking of those fault conclusions whose associated error condition is met;
• Determining a logical diagnostic result having at least one cause of error hypothesis based on the linked fault inferences;
• Calculate a probability of occurrence for each error cause hypothesis of the logical diagnosis result.

The The invention further provides a data carrier comprising such a computer program stores.

• – einer Speichereinheit zum Speichern von Diagnoseregeln, die jeweils eine Fehlerbedingung, welche das Vorhandensein eines Fehlers angibt, und eine Fehlerschlussfolgerung aufweisen, welche durch logische Verknüpfungen von potenziellen Fehlerursachen des jeweiligen Fehlers gebildet wird;
• – einer Logikeinheit, die diejenigen gespeicherten Fehlerschlussfolgerungen deren zugehörige Fehlerbedingungen erfüllt sind, logisch verknüpft und auf Grundlage der verknüpften Fehlerschlussfolgerungen ein logisches Diagnoseergebnis ermittelt, das mindestens eine Fehlerursachenhypothese aufweist; und
• – mit einer Berechnungseinheit, die eine Auftrittswahrscheinlichkeit für jede Fehlerursachenhypothese des logischen Diagnoseergebnisses berechnet.

The invention further provides a flying object component of a flying object, in particular of an aircraft, having a fault diagnosis device for optimizing maintenance measures in the flying object with:

• A memory unit for storing diagnostic rules each having an error condition indicating the presence of an error and a fault conclusion formed by logically linking potential causes of failure of the respective error;
• A logic unit that logically matches those stored fault conclusions whose associated fault conditions and, based on the linked fault inference, determines a logical diagnostic result having at least one fault cause hypothesis; and
• With a calculation unit which calculates an occurrence probability for each cause of error hypothesis of the logical diagnosis result.

• – einer Speichereinheit zum Speichern von Diagnoseregeln, die jeweils eine Fehlerbedingung, welche das Vorhandensein eines Fehlers angibt, und eine Fehlerschlussfolgerung aufweisen, welche durch logische Verknüpfungen von potenziellen Fehlerursachen des jeweiligen Fehlers gebildet wird;
• – einer Logikeinheit, die diejenigen gespeicherten Fehlerschlussfolgerungen deren zugehörige Fehlerbedingungen erfüllt sind, logisch verknüpft und auf Grundlage der verknüpften Fehlerschlussfolgerungen ein logisches Diagnoseergebnis ermittelt, das mindestens eine Fehlerursachenhypothese aufweist; und
• – mit einer Berechnungseinheit, die eine Auftrittswahrscheinlichkeit für jede Fehlerursachenhypothese des logischen Diagnoseergebnisses berechnet.

The invention further provides a flying object, in particular an aircraft, having at least one flying object component which has a fault diagnosis device for optimizing maintenance measures on the flying object:

• A memory unit for storing diagnostic rules each having an error condition indicating the presence of an error and a fault conclusion formed by logically linking potential causes of failure of the respective error;
• A logic unit that logically matches those stored fault conclusions whose associated fault conditions and, based on the linked fault inference, determines a logical diagnostic result having at least one fault cause hypothesis; and
• With a calculation unit which calculates an occurrence probability for each cause of error hypothesis of the logical diagnosis result.

• – einer Funkschnittstelle zum Empfangen von Fehlerursachenhypothesen-Auftrittswahrscheinlichkeiten von einem Flugobjekt; und mit
• – einer Wartungseinheit, die zu den Fehlerursachenhypothesen zugehörige Wartungsprozeduren entsprechend den empfangenen Fehlerursachenhypothesen-Auftrittswahrscheinlichkeiten vorbereitet und nach Landen des Flugobjektes an dem Zielflughafen nacheinander automatisch ausführt.

The invention further provides a maintenance device for servicing flying objects at a destination airport, comprising:

• A radio interface for receiving fault hypothesis occurrence probabilities from a flying object; and with
• A maintenance unit preparing the maintenance procedures associated with the fault cause hypotheses according to the received fault hypothesis occurrence probabilities, and automatically after landing the flying object at the destination airport successively performs.

in the Further will be embodiments the fault diagnosis device according to the invention the method according to the invention to optimize maintenance in a flying object with reference to the attached figures In order to explain Features essential to the invention described:

1 a flying object with a fault diagnosis device according to the invention;

2 a block diagram of a system for optimizing maintenance measures, which contains the fault diagnosis device according to the invention;

3 a flowchart of a possible embodiment of the method according to the invention for optimizing maintenance measures in a flying object;

4 a diagram illustrating a simple example of the inventive method for optimizing maintenance measures in a flying object;

5 an application example for explaining the method according to the invention for optimizing maintenance measures in a flying object;

6 an embodiment of diagnostic rules in the in 5 illustrated application example;

7A - 7E Examples for explaining the method according to the invention for optimizing maintenance measures in a flying object;

8A - 8C various display options for diagnostic knowledge, which is used in the method according to the invention for optimizing maintenance measures.

How to get out 1 can detect contains a flying object 1 For example, a passenger plane, at least one fault diagnosis device 2 according to the invention for optimizing maintenance of the flying object 1 , The fault diagnosis device 2 can over a network 3 with other aircraft components of the aircraft 1 be connected. The fault diagnosis device 2 has a radio interface to, for example, probabilities of occurrence of identified cause of fault hypotheses to a maintenance device 4 to transfer, for example, to a destination airport of the aircraft 1 located.

2 shows a block diagram for explaining the error diagnostic device according to the invention 2 , The fault diagnosis device 2 receives from one or more error detectors 5 Information about whether fault conditions have been met by several aircraft components or whether an error event has occurred. The fault detectors 5 may be integrated with other aircraft components or form independent aircraft components, such as sensors. The fault diagnosis device 2 contains a storage unit 2A for storing diagnostic rules each having an error condition indicating the presence of an error and a fault conclusion formed by logically linking potential causes of failure of the respective error.

In addition, the fault diagnosis device according to the invention contains 2 as they are in 2 is shown, a logic unit 2 B , those stored fault conclusions whose associated error conditions are met, logically linked together and determined on the basis of the linked fault conclusions a logical diagnosis result having at least one error cause hypothesis. The logic unit 2 B delivers the logical diagnostic result to a calculation unit 2C the fault diagnosis device 2 , The calculation unit 2C calculates a probability of occurrence for each error cause hypothesis of the logical diagnosis result. In one possible embodiment, the logic unit links 2 B those in the store 2A stored fault conclusions of those diagnostic rules logically AND their error conditions are met. The fulfillment of an error condition becomes the logic unit 2 B through the associated error detector 5 reported. The logic unit then determines 2 B automatically using logical Boolean calculation rules or simplification rules based on the linked error conclusions of the diagnostic rules, the logical diagnostic result. The determined logical diagnostic result contains at least one error cause hypothesis. The calculation unit 2C then calculates an associated occurrence probability for each error cause hypothesis of the logical diagnosis result. In one possible embodiment, the probability of occurrence for each error cause hypothesis is calculated on the basis of the individual failure probabilities of the aircraft components linked together in the error cause hypothesis.

In one possible embodiment, the calculation unit sorts 2C the error cause hypotheses of the logical diagnosis result corresponding to the calculated occurrence probabilities of the respective cause-of-error hypotheses. at According to a possible embodiment, the cause-of-error hypotheses are sorted into a list according to decreasing occurrence probability, with the cause-of-error hypothesis with the highest probability of occurrence occupying first place in the list.

At the in 2 illustrated embodiment, the flying object, ie the aircraft, 1 via a radio interface 6 , The calculation unit 2C transmits the calculated occurrence probabilities of the cause-of-error hypotheses of the logical diagnosis result via the radio interface 6 to the maintenance device 4 , The maintenance device 4 is for this purpose also to a radio interface 7 connected. A maintenance unit 4A maintains stored within the maintenance device maintenance procedures that in egg nem memory 4B are stored and are provided in each case to a fault cause hypothesis of a diagnosis result, depending on the calculated occurrence probabilities of the transmitted error cause hypotheses successively from until the reported error is corrected. In one possible embodiment, the flying object sends 1 still in flight mode or during the flight, the error hypotheses with the associated occurrence probabilities via the radio interface 6 to the bottom of the maintenance device 4 , Before the landing of the plane 1 Then the necessary maintenance procedures are prepared and after the landing of the flying object 1 automatically executed until the displayed error in the affected flight system is resolved. As the maintenance procedures already during flight operations of the aircraft 1 can be prepared, thereby the necessary maintenance times are significantly reduced. At the maintenance device 4 It can be a portable device after landing the aircraft 1 Can be connected via an interface with the respective affected flight system.

In one possible embodiment, each flight system of the aircraft 1 a separate fault diagnosis device 2 on. In an alternative embodiment, the flying object components of a flight system each have their own integrated fault diagnosis device 2 on.

at A flying object component may be any electrical or electronically monitored Construction component act in which an error may occur. Examples for flying object components are actuators, sensors, data or power lines, data transmission or switching units and data processing units, such as Computer or server.

In one possible embodiment, the data content of the storage unit 2A the fault diagnosis device 2 configurable via an interface.

3 shows a simple flowchart of a possible embodiment of the method according to the invention for optimizing maintenance measures in a flying object 1 , In a step S1, first of all elementary diagnostic rules are provided, for example by the manufacturer of the respective aircraft components, and the memory unit 2A the fault diagnosis device 2 configured accordingly.

in the Step S2, the error conditions are checked, i. H. it is stated whether one or more error conditions of configured diagnostic rules Fulfills or the corresponding error has occurred.

each Diagnostic rule consists of an error condition which indicates the presence indicates an error and from a fault conclusion which from a logical link of potential causes of the error.

In one possible embodiment, each potential cause of failure includes a flying object component and a functional state of that flying object component. If an error detector 5 In step S2, the fulfillment of an error condition or the occurrence of an error event is reported, the logic unit determines 2 B the fault diagnosis device 2 in step S3, a logical diagnostic result by ANDing together the fault conclusions of those diagnostic rules that have the fulfilled error condition. In this case, preferably by means of logical Boolean calculation or compression rules based on the linked fault conclusions, a logical diagnosis result, which has one or more fault cause hypotheses, by the logic unit 2 B automatically determined.

Subsequently, the calculation unit calculates 2C in step S4, the occurrence probabilities of all error causes hypotheses of the logical diagnosis result. This can be done on the basis of the logically linked together in the error cause hypothesis individual components. If, for example, two aircraft components are connected in series with one another and the error cause hypothesis is that both units connected in series are faulty, the probability of occurrence for this error cause hypothesis is given by multiplying the individual error probabilities of both series-connected units.

In a further step S5, the calculation unit sorts 2C the determined error causes hypotheses on the amount of the calculated occurrence probabilities and transmits these calculation results, for example via a radio interface to the maintenance device 4 , The maintenance device 4 then executes the maintenance procedures stored in the corresponding sorted sequence for the error cause hypotheses. In this case, preferably that maintenance procedure is carried out, which is solved to that error hypothesis, which has the greatest probability of occurrence. This has the advantage that the maintenance measure is targeted based on the most likely fault cause hypothesis as a basis. As a result, there is a high statistical probability that the duration for the required maintenance is minimized.

At the logic unit 2 B it can be a wired logic unit or logic software. The calculation unit 2C is z. A microprocessor, which may have access to stored individual fault probabilities of flight system components.

4 shows a diagram for explaining the method according to the invention for optimizing maintenance measures. In the in 4 Example shown are by error detectors 5 the fulfillment of three error conditions or the appearance of N different error events displayed. For each of these error conditions, an associated error conclusion of suspect or contemplated aircraft components or causes of errors in the memory unit 2A stored. In the in 4 In the example shown, the first error conclusion, which is formed by logical associations of potential error causes of the respective error, for the error condition "fault detection 1 is true": "A ∨ B", ie the error conclusion indicates that the potential cause of the error is the flying object component A or the flying object component B is.

The error conclusion for the second fault condition "Fault detection 2 is true" is at the in 2 illustrated simple example that the potential cause of failure by the flying object component A is formed.

The error conclusion and the Nth error condition "Fault detection N is true" is in the in 4 example shown the assumption that the flying object component C is faulty.

The logic unit 2 B the diagnostic device 2 linked to those stored fault conclusions whose logical error conditions are met logically with each other AND as in 4 shown. Subsequently, by means of predetermined Boolscher or compression rules based on linked error conclusions by the logic unit 2 B a logical diagnosis result is determined and sent to the calculation unit 2C issued. At the in 4 is shown as a logical diagnosis result (A ∧ C) to the calculation unit 2C issued. At the in 4 As shown in the simple example, the logical diagnosis result has only one error cause hypothesis, namely that either the flying object component A or the flying object component C is faulty.

5 shows a somewhat more complex application example for explaining the method according to the invention for optimizing maintenance measures in a flying object 1 , At the in 5 illustrated example includes a flight system of the aircraft 1 two replaceable components, for example, sensors L1, L2 as Line Replaceable Units LRU. These are connected via data lines (wires) W7, W8, W9 to data switching units or Remote Data Concentrators R1, R2. The data concentrator R1 in turn outputs the data via lines W1, W2, W3 to two control computers or central data processing input / output modules CPIOM C1, C2 provided in parallel. Furthermore, the data concentrator and the data concentrator R2 are connected via lines W4, W5, W6 to another CPIOM C3. Corresponding diagnostic rules in the diagnostic memory unit can be used for such a flight system 2A the fault diagnosis device 2 saved as in 6 is shown by way of example. An observing unit (Observer), for example a CPIOM or a control computer, executes application programs and observes various error conditions or elementary fault cases, with an error conclusion in memory for each error condition 2A is stored and is formed by logical links of potential causes of error of each observed error. An error conclusion, for example, consists of logical links of potentially suspected object components of the aircraft 1 which may be the cause of the error. At the in 6 The simple example shown are in the memory 2A stored six different elementary diagnostic rules.

For example, observe the in 5 shown CPIOM C1 or control computer C1 that he no longer receives data from both sensors L1 and L2 is the fault conclusion or suspected flight components: R1 or W1 or W2 or (L1 and L2) or (W2 and W8). If neither of the two sensors L1, L2 supplies more data to the control computer C1, there is thus the possibility that either the data concentrator R1 or the line W1 or the line W2 is faulty or de are perfect. Furthermore, there is the possibility that both L1 and L2 have failed at the same time or that at the same time the lines W7 and W8 have failed.

observed the control computer C2 that he no longer receives data from the sensors L1, L2 receives exists the possibility, that the data concentrator R1 or the line W3 or the line W2 is defective. Furthermore, there is a possibility that both the both sensors L1, L2 are defective or that both the line W7 and the line W8 are defective.

In this way, various diagnostic rules can be created and stored based on the existing in the flight system signal paths. In one possible embodiment, a fault conclusion of a diagnostic rule consists of logical operations of flying object components lying in a signal path leading to that flying object component which has an error detector for detecting the fault condition of the respective diagnosis rule. At the in 6 example shown has z. B. the control computer C1 via at least one error detector 5 to see if it receives data from the sensors L1, L2. Reports the error detector 5 the occurrence of the error condition, the corresponding error conclusion, which includes the logical linkage of potential error causes, from memory 2A read.

In one possible embodiment, all error conclusions are read out whose error conditions are met, and by the logic unit 2 B logically ANDed together. At the in 6 shown simple example performs the logic unit 2 B first, logical AND operations of the read-out error conclusions of the occurred error conditions. In the given example, if all six error conditions of the in 6 are met, the six different error conclusions read ANDed together.

The logical expression is:
(R1 or W1 or W2 or (L1 and L2) or (W7 and W8)) and (R1 or W3 or W2 or (L1 and L2) or (W7 and W8)) and (R1 or L1 or W7 or W4 or W5 ) and (R1 or W1 or W2) and (R1 or W2 or W3) and (R1 or W4 or W5)

Subsequently, the logic unit determines 2 B using predetermined Boolean calculation or compression rules, the logical expression linked to a logical diagnostic result that has at least one error cause hypothesis:
R1 or (W2 and W4) or (W2 and W5) or (W1 and W3 and W4) or (W1 and W3 and W5)

In one possible embodiment, the logic unit 2 B the logical diagnostic result is still converted into an EXOR form, in which various cause-of-error hypotheses are logically connected with each other via EXOR links.

At the in 5 . 6 Thus, a simple error-cause hypothesis appears when all six error conditions occur for the six different diagnostic rules that exist in the memory 2A are stored that the data concentrator R1 is defective. Another error cause hypothesis is that both the line W2 and the line W4 are defective. The third failure cause hypothesis is that both the W2 and W5 are defective. Another error cause hypothesis is that the line W1, the line W3 and the line W4 are defective. Another error cause hypothesis of the diagnostic result is that both the line W1 and the lines W3 and W5 are defective.

The different fault cause hypotheses found have different occurrence probabilities. For example, the likelihood of multiple system components failing simultaneously is typically less than the likelihood that a single system component will fail. In one possible embodiment, the calculation unit calculates 2C For each error cause hypothesis of the determined logical diagnosis result, a probability of occurrence, the probability of occurrence of a cause error hypothesis being calculated on the basis of the failure probabilities of the individual components. In one possible embodiment, the calculation unit 2C Access to a table that stores the probabilities of default for the various individual flying object components of the particular flight system. For example, the probability of failure for the data concentrator R1 is 0.1 and the probability of failure for the various lines W1-W8 is 0.01. In this case, the probability of occurrence for the error cause hypothesis R1 of the diagnosis result is identical to the probability of failure of the component R1, ie 0.1.

On the other hand, the occurrence probability for the second cause-of-error hypothesis W2 and W4, that is, both the line W2 and the line W4 has failed, is 0.01 × 0.01 = 0.0001 and thus much lower than the occurrence probability of the first cause-of-error hypothesis. At the in 6 In the example shown, the determined logical diagnostic result comprises five fault cause hypotheses F1, F2, F3, F4, F5. Is the probability of occurrence or error likely For the data concentrator R1 10 ^-1 and the failure probability of each line W 10 ^-2 , the following occurrence probabilities P result for the various error cause hypotheses F as follows:
F1: 10 ^-1
F2: 10 ^-4
F3: 10 ^-4
Q4: 10 ^-6
Q5: 10 ^-6

In this scenario, the probability of occurrence for the first cause of error hypothesis F1, ie, the data concentrator R1 is erroneous, thus highest. The calculation unit 2C transfers the calculated occurrence probabilities of the various cause-of-error hypotheses, for example the cause-of-error hypotheses F1-F5 of the logical diagnosis result, via the interface to the maintenance unit 4A which first executes the maintenance procedure provided for the fault occurrence hypothesis with the highest probability of occurrence. In this case, the maintenance unit performs 4A the maintenance procedure provided for the fault cause hypothesis F1. Subsequently, the further maintenance procedures for the further cause-of-error hypotheses F2-F5 are executed in accordance with the height of the calculated occurrence probability.

7A - 7F show simple examples to explain different scenarios. At the in 7A As shown, the flying object component A is defective, and this is observed by the two components B, C. The logical diagnostic result is: A ∧ A = A. This means that multiple instances or observations of the same causes of error can be reduced by a diagnostic result and thus the observations of different functions to be monitored can be compressed or observations can be corrected.

7B shows a faulty component B within a series connection, wherein the occurrence of a fault condition by a component A is observed. For example, component A observes the occurrence of an error with the simple diagnostic rule or error inference (A ∨ B ∨ C) and component B observes the occurrence of the error with diagnostic rule or error conclusion B.

This results in the following diagnostic result: (A ∨ B ∨ C) ∧ B = B For the in 7C example shown, the component B and the component C is defective. Component A observes the occurrence of the error of the corresponding diagnostic rule (A ∨ B ∨ C), component B observes the error with the diagnostic rule (B ∨ C) and component C observes the error with diagnostic rule C.

The the corresponding diagnostic result is: (A ∨ B ∨ C) ∧ (B ∨ C) ∧ (C = C).

At the in 7D the components B, C are also defective, with component B carrying out a different error conclusion according to the corresponding diagnostic rules, namely the conclusion B.

The corresponding logical diagnostic result is: (A ∨ B ∨ C) ∧ B ∧ C = B ∧ C

Storing the error diagnosis rules, in particular the associated error conclusions, can thus have an influence on the error diagnosis result. While in the case of 7C the diagnostic result is C, the error diagnosis result for the case is 7D (B ∧ C)

The 7B . 7C . 7D show the influence of the Boolean adaptation law A ∧ (A ∨ B) = A in the determination of a fault diagnosis result.

The 7E shows the influence of the Boolean distributive law for the determination of a diagnosis result: (A ∨ B) ∧ (A ∨ C) = A ∨ (B ∧ C).

Both in 7E As shown, a flying object component C is defective, and this is observed by the two components A and B (A ∨ B). The error conclusion of the diagnostic rules in the case of an error is for component A: (A ∨ C) and for component B: (B ∨ C).

The result of the diagnosis is as follows: (A ∨ C) ∧ (B ∨ C) = C ∨ (A ∧ B)

kick thus an error on the component C, is a fault cause hypothesis, that actually the component C has failed. The alternative fault cause hypothesis is that both observational components A, B have failed and thus a double error is present. Using the probabilities For example, the individual components can be used to prove that the probability of occurrence of the error cause hypothesis "Fail the error component C alone "more likely is.

7F shows the influence of the Boolean Associative Law in the calculation of a fault diagnosis result: (A ∧ B) ∧ C = A ∧ (B ∧ C))

At the in 7F As illustrated, three different aircraft systems are considered that may be interconnected. The aircraft system Sys1 contains the components A, B the aircraft system Sys2 contains the component C and the aircraft system Sys3 contains the component D. In the in 7F As shown, the component C and the component D is defective. An error in the component C in the system Sys2 leads to a given predefined fault condition PFC _C , which is observed, for example, by the components B, D of the other systems Sys1, Sys3. The overall diagnosis result of the entire system, which consists of the three subsystems Sys1, Sys2, Sys3, is: (A ∧ PFC C ) ∧ (C) ∧ (D ∧ PFC C ) = A ∧ C ∧ D

Based on the in 7F As illustrated, it can be seen that sub-diagnostic results of subsystems can be linked together to determine a diagnostic result for a whole system.

at a possible embodiment are maintenance procedures TSP (Trouble Shooting Procedures) for failure causes or groups of failure causes provided the same maintenance require. In one possible embodiment is for each fault cause hypothesis provided an associated maintenance procedure.

The Diagnostic knowledge or the error diagnosis rules are preferred based on specifications of the various system manufacturers or available from these posed.

8A . 8B . 8C show different display options for diagnostic knowledge or a diagnostic database. Diagnostic rules can, as in 8A represented, logically represented, but also graphically as in 8B shown. Furthermore, diagnostic rules can also be tabulated as in 8C shown, wherein such a configuration table, for example, in a memory 2A can be stored.

at the method according to the invention can Maintenance procedures of different causes or different Error cause hypotheses are prepared or provided, which the same maintenance require.

The Inventive diagnostic method for Optimization of maintenance measures in an aircraft is capable of all possible error events and To consider event combinations the possible ones Error causes of flight operations to combine and due to the Diagnostic result to prepare the appropriate maintenance procedures or to initiate directly. Due to the possible preparation of the maintenance measures and the targeted preparation of the maintenance procedures initially for the most likely Error cause hypotheses become, the maintenance times significantly reduced.

The inventive method for the diagnosis of causes of errors and for the optimization of maintenance measures be dynamic and automatic during the life of the various flight systems executed. It can therefore also flexibly evaluate fault scenarios that are a development engineer not in the development or design of the respective flight system considered Has. This will in addition increased the safety of flight operations. The use of Booleans Calculation and compression rules allow a secure and fast evaluation of the diagnostic results. The inventive method uses logical inferences to efficiently detect errors in flight systems to possible faulty Close system components.

1

Flying object plane

2

The diagnostic device

2A

Storage, Diagnosis storage unit

2 B

logic unit

2C

calculation unit

3

network

4

maintenance device

4A

maintenance unit

4B

maintenance procedures

5

error detectors

6 7

Radio interface

C1

tax calculator

C2

tax calculator

CPIOM C1, C2, C3

Data processing unit / output modules

L1, L2

sensors

R1, R2

Data concentrator

W1-W8

cables

Sys1

system 1

Sys2

system 2

Sys3

system 3

Claims (23)

Fault diagnosis device ( 2 ) For optimizing maintenance actions in a system comprising: (a) a memory unit ( 2A ) for storing diagnostic rules, each indicating an error condition indicating the presence of an error, and have an error conclusion, which is formed by logical connections of potential causes of error of the respective error; (b) a logic unit ( 2 B ) logically associating those stored fault conclusions with their associated fault conditions, and determining a logical diagnostic result having at least one fault cause hypothesis based on the linked fault inferences; and (c) with a calculation unit ( 2C ) which calculates an occurrence probability for each error cause hypothesis of the logical diagnosis result. Fault diagnostic device according to claim 1, wherein the calculation unit ( 2C ) the calculated occurrence probabilities of the error cause hypotheses of the logical diagnosis result via an interface ( 6 . 7 ) to a maintenance device ( 4 ) transmits. Fault diagnostic device according to claim 2, wherein the maintenance device ( 4 ) a maintenance unit ( 4A ), which maintenance procedures, which are provided in each case to a fault cause hypothesis of the diagnosis result, in succession executes in dependence on the calculated occurrence probabilities of the cause of error hypothesis until the error is corrected. Fault diagnostic device according to claim 1, wherein the calculation unit ( 2C ) sorts the cause-of-error hypotheses of the logical diagnosis result according to the calculated occurrence probabilities of the cause-of-error hypotheses. Fault diagnostic device according to claim 1, wherein the fault diagnosis device ( 2 ) in an object ( 1 ) of the system, in particular a flying object, is provided. Fault diagnostic device according to claim 5, wherein the fault diagnosis device ( 2 ) the calculated occurrence probabilities of the fault cause hypotheses via a radio interface in a flight operation of the flying object ( 1 ) to the maintenance device ( 4 ) located at a destination airport of the flying object ( 1 ) to prepare maintenance measures. Fault diagnostic device according to claim 1, wherein the logic unit ( 2 B ) logically ANDs the stored fault conclusions of the diagnostic rules. Fault diagnostic device according to claim 7, wherein the logic unit ( 2 B ) automatically determines the logical diagnostic result by means of logical Boolean calculation rules on the basis of the linked error conclusions of the diagnostic rules. Fault diagnostic device according to claim 5, wherein to fulfill an error condition, a diagnostic rule by an error detector ( 5 ) of a flying object component within the flying object ( 1 ) is detected. Fault diagnostic apparatus according to claim 9, wherein a diagnostic rule consists of logical links of flying object components lying in a signal path leading to the flying object component comprising the fault detector ( 5 ) for detecting the error condition of the diagnostic rule. Fault diagnostic apparatus according to claim 1, wherein for every Root cause hypothesis at least one associated maintenance procedure (TSP) is present, which includes several maintenance activities. Fault diagnostic device according to claims 3, 11, wherein the maintenance procedures (TSP) by the maintenance unit sorted in the order of occurrence probabilities of associated root cause hypotheses accomplished become. Fault diagnostic apparatus according to claim 10, wherein the potential causes of failure are each a flying object component and have a functional state of this flying object component. Fault diagnostic device according to claim 9, wherein the flying object components of the flying object ( 1 ) Actuators, sensors, lines, data switching units and data processing units. Method for optimizing maintenance activities for an object of a system, with the following steps: (A) Providing (S1) diagnostic rules, each having an error condition, which indicates the presence of an error and has a fault conclusion, which from a logical link of potential causes of the error; (b) logical Link (S3) of those fault conclusions their associated error condition Fulfills (S2) is for determining a logical diagnosis result, which has at least one cause of error hypothesis. (c) Calculate (S4) a probability of occurrence for each error cause hypothesis the determined logical diagnosis result. The method of claim 15, wherein the error cause hypotheses are calculated according to the the probability of occurrence is sorted (S5) and maintenance procedures associated with the cause-of-error hypotheses are executed in the order of the sorted cause-of-error hypotheses. Method according to claim 15, wherein the presence of an error by an error detector ( 5 ) during operation of the object ( 1 ), in particular a flying object, is detected. The method of claim 17, wherein the order of the sorted fault cause hypotheses after detection of a fault at a destination airport of the flying object ( 1 ) is sent via a radio interface for the preparation of appropriate maintenance procedures. Computer program for carrying out a method according to the claims 15 to 18. disk, which stores the computer program of claim 19. Flying object component with a fault diagnosis device according to claim 1 to 14. Flying object with at least one flying object component according to claim 21. Maintenance device ( 4 ) for the maintenance of flying objects ( 1 ) at a destination airport, comprising: (a) a radio interface ( 7 ) for receiving fault hypothesis occurrence probabilities from a flying object ( 1 ); and (b) a maintenance unit ( 4A ) prepares the maintenance procedures (TSP) associated with the cause-of-error hypotheses according to the received cause-of-error hypothesis occurrence probabilities and after landing the flying object ( 1 ) automatically runs one after the other at the destination airport.