# US 10,481,989 B2 · Method and apparatus for generating a fault tree for a failure mode of a multi-mode system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,989 B2 - Document ID: US10481989B2 - Status: Granted - Kind: B2 - Application number: 15/249,685 - Filed: 2016-08-29 - Published: 2017-05-11 - Granted: 2019-11-19 - Earliest claimed: 2015-10-02 - Assignees: Siemens Aktiengesellschaft - Applicants: Siemens Aktiengesellschaft - Inventors: Kai Höfig; Marc Zeller - Web page: https://patentgrep.com/patent/US10481989B2 ## CPC - G06F 11/2257: {using expert systems} - G05B 23/0248: {Causal models, e.g. fault tree; digraphs; qualitative physics} - G06F 11/004: {Error avoidance (G06F11/07 and subgroups take precedence)} - G06F 11/008: {Reliability or availability analysis} - G06F 11/0736: {in functional embedded systems, i.e. in a data processing system designed as a combination of hardware and software dedicated to performing a certain function (testing or monitoring of automated control systems G05B23/02)} - G06F 11/0751: {Error or fault detection not based on redundancy (power supply failures G06F1/30; network fault management H04L41/06)} - G06F 11/079: {Root cause analysis, i.e. error or fault diagnosis (in a hardware test environment G06F11/22; in a software test environment G06F11/36)} - G06F 11/2252: {using fault dictionaries} - G06F 16/2246: {Trees, e.g. B+trees} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract A method and apparatus for generating a fault tree for a failure mode of a multi-mode system which includes a plurality of system components, the method includes the steps of providing component fault tree elements of the system components, wherein each component fault tree element includes at least one component fault tree mode element, representing a failure-relevant operation mode of the respective system component; selecting at least one component fault tree mode element representing a system state of the system; and generating the fault tree by incorporating the selected component fault tree mode elements the generated fault tree representing a failure behaviour of a system state of the system. ## Claims ### Claim 1 A method for generating a fault tree for a failure mode of a multi-mode system comprising a plurality of system components, said method comprising the steps of: (a) providing component fault tree elements of the system components, wherein each component fault tree element includes at least one component fault tree mode element representing a failure-relevant operation mode of the respective system component, and at least one component fault tree element comprises a plurality of component fault tree mode elements, wherein each component fault tree mode element of the plurality of component fault tree mode elements of the at least one component fault tree element receives the same output from a previous component fault tree element and each component fault tree mode element results in failure at a single outport; (b) selecting at least one component fault tree mode element representing a system state of said system; and (c) generating the fault tree by incorporating the at least one selected component fault tree mode element, said generated fault tree representing a failure behaviour of a system state of said system. ### Claim 2 (depends on 1) The method according to claim 1, wherein the generated fault tree is reduced by applying a Boolean logic to create a reduced fault tree for a selected output failure mode of the fault tree. ### Claim 3 (depends on 1) The method according to claim 1, wherein the method is performed in a normal operation mode of said system during runtime. ### Claim 4 (depends on 1) The method according to claim 1, wherein the method is performed in a separate operation mode of said system, during deployment of components, during configuration or reconfiguration of a component of said system and/or during maintenance or repair of a component of said system. ### Claim 5 (depends on 1) The method according to claim 1, wherein the failure-relevant operation mode of the system comprises a start-up operation mode, a calibration operation mode, a degraded operation mode and/or an emergency operation mode. ### Claim 6 (depends on 1) The method according to claim 1, wherein the system components comprise hardware components and/or software components. ### Claim 7 (depends on 1) The method according to claim 1, wherein the component fault tree elements and the component fault tree mode elements of the system components are loaded from a library stored in a database. ### Claim 8 (depends on 2) The method according to claim 2, wherein the reduced fault tree is evaluated to quantify and/or qualify the failure behaviour of the respective system state. ### Claim 9 (depends on 1) The method according to claim 1, wherein each component fault tree mode element of the plurality of component fault tree mode elements of the at least one component fault tree element models an operating mode specific failure behaviour of a component of the system of the components. ### Claim 10 An apparatus for generating a fault tree for a failure mode of a multi-mode system, the apparatus connected to the multi-mode system and adapted to: input a plurality of component fault tree elements of system components of the multi-mode system, wherein each component fault tree element includes at least one component fault tree mode element representing a failure-relevant operation mode of the respective system component, and at least one component fault tree element includes a single inport from a previous component fault tree element and a plurality of component fault tree mode elements that receive the same input through the single inport and result in failure at a single outport of the at least one component fault tree element; select at least one component fault tree mode element representing a system state of the multi-mode system; and generate the fault tree by incorporating the at least one selected component fault tree mode element wherein the generated fault tree represents a failure behaviour of a system state of the multi-mode system. ### Claim 11 (depends on 10) The apparatus according to claim 10, wherein each component fault tree mode element of the plurality of component fault tree mode elements models an operating mode specific failure behaviour of a component of the system of the components.