Diagnostic method and system

• US 7,409,317 B2
• Filed: 11/22/2005
• Issued: 08/05/2008
• Est. Priority Date: 12/21/2004
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Neyt, Jean-Lois, Cousin, Benoit
• Primary Examiner(s): Barbee; Manuel L
• Application Number:
  US11/285,627
• Publication Number:
  US 20060150018A1
• Time in Patent Office: 987 Days
• Field of Search: 702/58, 702/59, 702182-185, 702/188, 701/29, 701 31- 35, 706911-918
• US Class Current: 702/183
• CPC Class Codes: G05B 23/0248 Causal models, e.g. fault tree; digraphs; qualitative physics
• CPC Class Codes: G05B 23/0278 Qualitative, e.g. if-then rules; Fuzzy logic; Lookup tables; Symptomatic search; FMEA
• CPC Class Codes: G06F 11/2257 using expert systems

Abstract

A method and system comprising a diagnostic symptom tree system for diagnosing a failing system element causing a symptom in a system-under-test. A diagnostic symptom tree comprises symptom roots and dependent lower function nodes and sub-function nodes. Element nodes depend from the function or sub-function nodes, and a plurality of penultimate failure mode leaves depend from the element nodes. The function and sub-function nodes and the failure mode leaves comprise test information. Responsive to positive test results, the diagnostic symptom tree is configured to identify a function or sub-function or element node associated to a lowest symptom tree node or failure mode leaf for which a test is positive, or advise that no failing function or sub-function or element is found. In one aspect of the invention, nodes may include parameter values allowing successive selections of the nodes of the symptom tree for test iterations according to the parameter values.

Claims

1. A method for diagnosing a failing replaceable element causing a symptom in a vehicle, said method comprising:

a programmable device operating a diagnostic application in communication with at least one database component and a vehicle reading a unique vehicle identification number from the vehicle and diagnosing a failing replaceable element by;

generating a list of plurality electronic control units associated with the vehicle identification number from data residing in the at least one database component;

sending a communication protocol request to each of the listed vehicle electronic control units and detecting a plurality of the listed vehicle electronic control units responding with a positive answer;

retrieving vehicle configuration data comprising parameters and diagnostic trouble codes from the responding plurality of electronic control units;

building a configuration image of the vehicle by consolidating the vehicle configuration data with as-built material data from the at least one database component, the as-built material data associated with the vehicle identification number;

building a pruned failure symptom diagnostic tree adapted to the configuration image by extracting a symptom tree comprising a tree root associated with a selected vehicle failure symptom from a diagnostic tree database in the at least one database component, the extracted tree comprising a plurality of function nodes depending from the tree root, pruning function nodes not corresponding to the configuration image, the pruned tree further comprising a plurality of replaceable-element nodes depending from the function nodes, a plurality of penultimate failure mode leaves depending from the replaceable-element nodes, and a node plurality of automatic tests and a plurality of manual confirmation tests associated with each of the nodes;

storing a node value in each of the nodes, the node value a test cost value or a failure mode occurrence frequency value;

ordering the pruned tree by selecting nodes having a first node value and prioritizing the manual confirmation tests in response to a manual confirmation test value associated with each of the manual tests;

executing at least one of the associated automatic node tests and at least one of the associated manual confirmation tests for selected nodes of the depending nodes by putting the vehicle into a context, prioritizing and selecting automatic tests associated with each of the pruned tree nodes in response to the vehicle context and to the vehicle configuration data parameters, executing selected prioritized automatic tests by building logical expressions from the parameters and the diagnostic trouble codes, and if a built logical expression associated with a one of the pruned tree nodes is true, and asking an operator to perform at least one of the manual tests associated with the true pruned tree node as prioritized; and

reporting an element associated to a one of the leaves depending from the selected nodes as the replaceable element responsive to positive test results of a selected node performed automatic test and a selected node performed manual confirmation test if the performed manual confirmation test returns a confirmed answer;

or

if no performed manual confirmation test returns a confirmed answer, ordering a second diagnostic symptom tree comprising pruned tree nodes each having a second node value, and if a second diagnostic symptom tree manual-node test result is positive, performing lower second diagnostic symptom tree depending node manual-node tests and reporting an element associated to a lowest node in the second diagnostic symptom tree for which an associated manual-node test is positive as the failing part;

or

ordering a third diagnostic symptom tree comprising pruned tree nodes each having a third node value and, if a third diagnostic symptom tree manual-node test result is positive, then performing lower third diagnostic symptom tree depending node manual-node tests and reporting an element associated to a lowest node in the third diagnostic symptom tree for which an associated manual-node test is positive as the failing part, wherein the first, second and third parameter values are divergent;

or

reporting that no failing part is found in response to a negative test result from each of the performed tests;

wherein prioritizing the automatic tests or the manual confirmation tests comprises prioritizing by applying an algorithm to the node values.

2. The method of claim 1 wherein the retrieved vehicle configuration data parameters and the stored node values comprise a feature model value;

wherein consolidating the vehicle configuration data comprises validating a feature model value in response to the vehicle identification number; and

wherein building the pruned failure symptom diagnostic tree comprises selecting nodes having the validated feature model value.

3. The method of claim 2 wherein ordering the pruned tree, the second diagnostic symptom tree and third diagnostic symptom tree comprises prioritizing node tests in lists responsive to:

a test difficulty value;

at least one of a test occurrence frequency value or a test failure likelihood value; and

a test truth weight value;

wherein the pruned tree node test difficulty values, test occurrence frequency values, test failure likelihood values or test truth weight values each have a lower test context than a corresponding node second diagnostic symptom tree test difficulty value, test occurrence frequency value, test failure likelihood value or test truth weight value; and

wherein the third diagnostic symptom tree node manual confirmation tests each require replacing a replaceable element to determine element functioning.

4. A method for deploying an application for diagnosing a failing replaceable element causing a symptom in a vehicle, the method comprising:

providing a computer infrastructure being operable to communicate with at least one database component and a vehicle, the computer infrastructure operable to read a unique vehicle identification number from the vehicle and diagnose a failing replaceable element by;

generating a list of a plurality of electronic control units associated with the vehicle identification number from data residing in the at least one database component;

sending a communication protocol request to each of the listed vehicle electronic control units and detecting a plurality of the listed vehicle electronic control units responding with a positive answer;

retrieving vehicle configuration data comprising parameters and diagnostic trouble codes from the responding plurality of electronic control units;

building a configuration image of the vehicle by consolidating the vehicle configuration data with as-built material data from the at least one database component, the as-built material data associated with the vehicle identification number;

building a pruned failure symptom diagnostic tree adapted to the configuration image by extracting a symptom tree comprising a tree root associated with a selected vehicle failure symptom from a diagnostic tree database in the at least one database component, the extracted tree comprising a plurality of function nodes depending from the tree root, pruning function nodes not corresponding to the configuration image, the pruned tree further comprising a plurality of replaceable-element nodes depending from the function nodes, a plurality of penultimate failure mode leaves depending from the replaceable-element nodes and a node plurality of automatic tests and a plurality of manual confirmation tests associated with each of the nodes;

storing a node value in each of the nodes the node value a test cost value or a failure mode occurrence frequency value;

ordering the pruned tree by selecting nodes having a first node value and prioritizing the manual confirmation tests in response to a manual confirmation test value associated with each of the manual tests;

executing at least one of the associated automatic node tests and at least one of the associated manual confirmation tests for selected nodes of the depending nodes by putting the vehicle into a context, prioritizing, and selecting automatic tests associated with each of the pruned tree nodes in response to the vehicle context and to the vehicle configuration data parameters, execution selected prioritized automatic tests by building logical expressions from the parameters and the diagnostic trouble codes, and if a built logical expression associated with a one of the pruned tree nodes is true, and asking an operator to perform at least one of the manual tests associated with the true pruned tree node as prioritized; and

reporting an element associated to a one of the leaves depending from the selected nodes as the replaceable element responsive to positive test results of a selected node performed automatic test and a selected node performed manual confirmation test if the performed manual confirmation test returns a confirmed answer;

or

if no performed manual confirmation test returns a confirmed answer, ordering a second diagnostic symptom tree comprising pruned tree nodes each having a second node value, and if a second diagnostic symptom tree manual-node test result is positive, performing lower second diagnostic symptom tree depending node manual-node tests, and reporting an element associated to a lowest node in the second diagnostic symptom tree for which an associated manual-node test is positive as the failing part;

or

ordering a third diagnostic symptom tree comprising pruned tree nodes each having a third node value and, if a third diagnostic symptom tree manual-node test result is positive, then performing lower third diagnostic symptom tree depending node manual-node tests and reporting an element associated to a lowest node in the third diagnostic symptom tree for which an associated manual-node test is positive as the failing part, wherein the first, second and third node values are divergent;

or

reporting that no failing part is found in response to a negative test result from each of the performed tests;

wherein prioritizing the automatic tests or the manual confirmation tests comprises prioritizing by applying an algorithm to the node values.

5. The method of claim 4 wherein the retrieved vehicle configuration data parameters and the stored node values comprise a feature model value;

wherein the computer infrastructure is further operable to consolidate the vehicle configuration data by validating a feature model value in response to the vehicle identification number, and building the pruned failure symptom diagnostic tree by selecting nodes having the validated feature model value.

6. The method of claim 5 wherein the computer infrastructure is further operable to order the pruned tree, the second diagnostic symptom tree and the third diagnostic symptom tree by prioritizing node tests in lists responsive to:

a test difficulty value;

at least one of a test occurrence frequency value or a test failure likelihood value; and

a test truth weight value;

wherein the pruned tree node test difficulty values, test occurrence frequency values, test failure likelihood values or test truth weight values each have a lower test context than a corresponding node second diagnostic symptom tree test difficulty value, test occurrence frequency value, test failure likelihood value or test truth weight value; and

wherein the third diagnostic symptom tree node manual confirmation tests each require replacing a replaceable element to determine element functioning.

7. A method for diagnosing a failing replaceable element causing a symptom in a vehicle, the method comprising:

producing computer executable program code;

storing the code on a computer readable medium; and

providing the program code to be deployed and executed on a computer system in communication with at least one database component and a vehicle;

the program code comprising instructions which, when executed on the computer system, cause the computer system to read a unique vehicle identification number from the vehicle and diagnose a failing replaceable element by;

generating a list of a plurality of electronic control units associated with the vehicle identification number from data residing in the at least one database component;

sending a communication protocol request to each of the listed vehicle electronic control units and detecting a plurality of the listed vehicle electronic control units responding with a positive answer;

retrieving vehicle configuration data comprising parameters and diagnostic trouble codes from the responding plurality of electronic control units;

building a configuration image of the vehicle by consolidating the vehicle configuration data with as-built material data from the at least one database component, the as-built material data associated with the vehicle identification number;

building a pruned failure symptom diagnostic tree adapted to the configuration image by extracting a symptom tree comprising a tree root associated with a selected vehicle failure symptom from a diagnostic tree database in the at least one database component, the extracted tree comprising a plurality of function nodes depending the tree root, pruning function nodes not corresponding to the configuration image, the pruned tree further comprising a plurality of replaceable-element nodes depending from the function nodes, a plurality of penultimate failure mode leaves depending from the replaceable-element nodes, and a node plurality of automatic tests and a plurality of manual confirmation tests associated with each of the nodes;

storing a node value in each of the nodes, the node value a test cost value or a failure mode occurrence frequency value;

ordering the pruned tree by selecting nodes having a first node value and prioritizing the manual confirmation tests in response to a manual confirmation test value associated with each of the manual tests;

executing at least one of the associated automatic node tests and at least one of the associated manual confirmation tests for selected nodes of the depending nodes by putting the vehicle into a context, prioritizing and selecting automatic tests associated with each of the pruned tree nodes in response to the vehicle context and to the vehicle configuration data parameters, executing selected prioritized automatic tests by building logical expressions from the parameters and the diagnostic trouble codes and if a built logical expression associated with a one of the pruned tree nodes is true, and asking an operator to perform at least one of the manual tests associated with the true pruned tree node as prioritized; and

reporting an element associated to a one of the leaves depending from the selected nodes as the replaceable element responsive to positive test results of a selected node performed automatic test and a selected node performed manual confirmation test if the performed manual confirmation test returns a confirmed answer;

or

if no performed manual confirmation test returns a confirmed answer, ordering a second diagnostic symptom tree comprising pruned tree nodes each having a second node value and if a second diagnostic symptom tree manual-node test result is positive, performing lower second diagnostic symptom tree depending node manual-node tests, and reporting an element associated to a lowest node in the second diagnostic symptom tree for which an associated manual-node test is positive as the failing part;

or

ordering a third diagnostic symptom tree comprising pruned tree nodes each having a third node value and, if a third diagnostic symptom tree manual-node test result is positive, then performing lower third diagnostic symptom tree depending node manual-node tests and reporting an element associated to a lowest node in the third diagnostic symptom tree for which an associated manual-node test is positive as the failing part, wherein the first, second and third node values are divergent;

or

reporting that no failing part is found in response to a negative test result from each of the performed tests;

wherein prioritizing the automatic tests or the manual confirmation tests comprises prioritizing by applying an algorithm to the node values.

8. The method of claim 7 wherein the retrieved vehicle configuration data parameters and the stored node values comprise a feature model value;

the program code further comprising instructions which, when executed on the computer system, cause the computer system to consolidate the vehicle configuration data by validating a feature model value in response to the vehicle identification number, and building the pruned failure symptom diagnostic tree by selecting nodes having the validated feature model value.

9. The method of claim 8, the program code further comprising instructions which, when executed on the computer system, cause the computer system to order the pruned tree, the second diagnostic symptom tree and the third diagnostic symptom tree by prioritizing node tests in lists responsive to:

a test difficulty value;

at least one of a test occurrence frequency value or a test failure likelihood value; and

a test truth weight value;

wherein the pruned tree node test difficulty values, test occurrence frequency values, test failure likelihood values or test truth weight values each have a lower test context than a corresponding node second diagnostic symptom tree test difficulty value, test occurrence frequency value, test failure likelihood value or test truth weight value; and

wherein the third diagnostic symptom tree node manual confirmation tests each require replacing a replaceable element to determine element functioning.