Method of fault diagnosis in an apparatus having sensors
First Claim
1. A fault diagnosis method for diagnosing an apparatus comprising a plurality of sensor nodes and a plurality of part nodes which are directly or indirectly associated with said plurality of sensor nodes, comprising the steps of:
- a) before fault diagnosis,a1) setting linkages based on deliveries of signals among said plurality of sensor nodes and said plurality of part nodes, and establishing weighing factors indicating correlations between said plurality of sensor nodes and said plurality of part nodes forming the linkages;
a2) classifying said plurality of sensor nodes and said plurality of part nodes into a plurality of subsystems;
b) during fault diagnosis;
b1) collecting output signals of said plurality of sensor nodes;
b2) converting the collected output signals of the plurality of sensor nodes to state quantities indicating degree of abnormal operation of the plurality of sensor nodes;
b3) calculating state quantities indicating an abnormal operation of respective part nodes having a linkage with respective sensor nodes;
b4) consolidating the state quantities for the plurality of sensor nodes and the plurality of part nodes obtained at steps b2 and b3 for each of said plurality of subsystems; and
b5) performing fault diagnosis on said plurality of sensor nodes and the plurality of part nodes on the basis of the consolidated results of step b4, wherein a state quantity value is used as a basis for fault diagnosis.
1 Assignment
0 Petitions
Accused Products
Abstract
The relationships between part nodes, including all sensor nodes in an apparatus system are expressed by connecting relations and weighing factors indicating the correlation. Output signals of all the sensor nodes in the system are converted to a state quantity by a membership function using fuzzy reasoning. With a sensor as a starting point, the nodes which are sequentially connected are traced and state quantities of each node are determined. The state quantities of each node are unified in a subsystem comprising this apparatus system and the subsystem in which the value of the state quantity is large is inferred to be faulty.
-
Citations
16 Claims
-
1. A fault diagnosis method for diagnosing an apparatus comprising a plurality of sensor nodes and a plurality of part nodes which are directly or indirectly associated with said plurality of sensor nodes, comprising the steps of:
-
a) before fault diagnosis, a1) setting linkages based on deliveries of signals among said plurality of sensor nodes and said plurality of part nodes, and establishing weighing factors indicating correlations between said plurality of sensor nodes and said plurality of part nodes forming the linkages; a2) classifying said plurality of sensor nodes and said plurality of part nodes into a plurality of subsystems; b) during fault diagnosis; b1) collecting output signals of said plurality of sensor nodes; b2) converting the collected output signals of the plurality of sensor nodes to state quantities indicating degree of abnormal operation of the plurality of sensor nodes; b3) calculating state quantities indicating an abnormal operation of respective part nodes having a linkage with respective sensor nodes; b4) consolidating the state quantities for the plurality of sensor nodes and the plurality of part nodes obtained at steps b2 and b3 for each of said plurality of subsystems; and b5) performing fault diagnosis on said plurality of sensor nodes and the plurality of part nodes on the basis of the consolidated results of step b4, wherein a state quantity value is used as a basis for fault diagnosis. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A fault diagnosis method for diagnosing an apparatus system which comprises a plurality of sensor nodes and a plurality of part nodes which are directly or indirectly associated with the plurality of sensor nodes, comprising the steps of:
-
a) before fault diagnosis, a1) setting linkages based on deliveries of signals among said plurality of sensor nodes and said plurality of part nodes, establishing weighing factors indicating correlations between any of the plurality of sensor nodes and plurality of part nodes forming the linkages, and assigning fault information on the basis of experiences to each sensor and part node; a2) classifying said plurality of sensor nodes and said plurality of part nodes into a plurality of subsystems; b) at fault diagnosis time; b1) collecting output signals of said plurality of sensor nodes; b2) converting the collected output signals of the sensor nodes to state quantities indicating a degree of abnormality of the sensor nodes; b3) inferring a faulty state of a sensor node by calculating a state quantity indicating a state of abnormality for every sensor node along with the linkages, while calculating a state quantity for part nodes on the basis of said sensor state quantity indicating the state of abnormality; b4) processing the two results, obtained in step b3 for their respective subsystems; and b5) performing fault diagnosis on said plurality of sensor nodes and part nodes on the basis of the processed results of step b4. - View Dependent Claims (14, 15, 16)
-
Specification