Multivariate analysis of wireless sensor network data for machine condition monitoring
View Patent ↗Machine condition monitoring on a system utilizes a wireless sensor network to gather data from a large number of sensors. The data is processed using a multivariate statistical model to determine whether the system has deviated from a normal condition. The wireless sensor network permits the acquisition of a large number of distributed data points from plural system modalities, which, in turn, yields enhanced prediction accuracy and a reduction in false alarms.
1. A method for performing maintenance on a system, the method comprising:
measuring data using a plurality of wireless sensors in a wireless sensor network, the data representing a plurality of modalities of the system;
transmitting the data via wireless radio signals from the wireless sensors to one or more base stations;
comparing the data to a multivariate statistical model representing normal machine conditions, wherein relationships among sensor data representing plural modalities are considered; and
performing maintenance on the system according to results of the comparing;
wherein transmitting the data via wireless radio signals from the wireless sensors to one or more base stations further comprises:
creating a routing topology wherein wireless radio signals are routed from wireless sensors through other wireless sensors to the one or more base stations;
identifying at least one wireless sensor having a degraded signal; and
altering the routing topology to avoid routing wireless radio signals through the one identified wireless sensor.
2. The method of claim 1 , wherein the step of transmitting the data via wireless radio signals from the wireless sensors to one or more base stations includes:
utilizing ZIGBEE wireless protocol.
3. The method of claim 1 , wherein transmitting the data via wireless radio signals from the wireless sensors to one or more base stations includes:
transmitting the data through a mesh network.
4. The method of claim 3 , wherein at least one of the wireless sensors also functions as a router.
5. The method of claim 1 , further comprising:
processing the data in the base station using middleware implementing a service-oriented architecture (SOA); and
transmitting the processed data to a remote location for performing the comparing step.
6. The method of claim 1 , further comprising creating the multivariate statistical model by:
measuring training data during normal operation of the system using the plurality of wireless sensors in the wireless sensor network;
transmitting the training data via the wireless radio signals from the wireless sensors to one or more base stations; and
creating the multivariate statistical model representing normal machine conditions by representing a normal condition of the system as a region in a multidimensional sensor space.
7. The method of claim 6 ,:
wherein the comparing comprises determining whether the measured data falls within the normal region.
8. The method of claim 6 , wherein the region representing a normal condition is determined using a regression-based algorithm.
9. The method of claim 1 , wherein the plurality of wireless sensors in the wireless sensor network includes redundant wireless sensors measuring a same modality.
10. The method of claim 1 , wherein the plurality of wireless sensors in the wireless sensor network includes wireless sensors measuring a same modality at different locations, and wherein the results of the comparing include a location of a fault in the system.
11. A computer-usable medium having computer readable instructions stored thereon for execution by a processor to perform a method for performing maintenance on a system, the method comprising:
measuring data using a plurality of wireless sensors in a wireless sensor network, the data representing a plurality of modalities of the system;
transmitting the data via wireless radio signals from the wireless sensors to one or more base stations;
comparing the data to a multivariate statistical model representing normal machine conditions, wherein relationships among sensor data representing plural modalities are considered; and
performing maintenance on the system according to results of the comparing;
wherein transmitting the data via wireless radio signals from the wireless sensors to one or more base stations further comprises:
creating a routing topology wherein wireless radio signals are routed from wireless sensors through other wireless sensors to the one or more base stations;
identifying at least one wireless sensor having a degraded signal; and
altering the routing topology to avoid routing wireless radio signals through the one identified wireless sensor.
12. The computer-usable medium of claim 11 , wherein transmitting the data via wireless radio signals from the wireless sensors to one or more base stations includes:
utilizing ZIGBEE wireless protocol.
13. The computer-usable medium of claim 11 , wherein transmitting the data via wireless radio signals from the wireless sensors to one or more base stations includes:
transmitting the data through a mesh network.
14. The computer-usable medium of claim 13 , wherein at least one of the wireless sensors also functions as a router.
15. The computer-usable medium of claim 11 , wherein the method further comprises:
processing the data in the base station using middleware implementing a service-oriented architecture (SOA); and
transmitting the processed data to a remote location for performing the comparing.
16. The computer-usable medium of claim 11 , wherein the method further comprises creating the multivariate statistical model by:
measuring training data during normal operation of the system using the plurality of wireless sensors in the wireless sensor network;
transmitting the training data via the wireless radio signals from the wireless sensors to one or more base stations; and
representing a normal condition of the system as a region in a multidimensional sensor space.
17. The computer-usable medium of claim 16 , wherein the method further comprises:
wherein the comparing comprises determining whether the measured data falls within the normal region.
18. The computer-usable medium of claim 16 , wherein the region representing a normal condition is determined using a regression-based algorithm.
19. The computer-usable medium of claim 11 , wherein the plurality of wireless sensors in the wireless sensor network includes redundant wireless sensors measuring a same modality.
20. The computer-usable medium of claim 11 , wherein the plurality of wireless sensors in the wireless sensor network includes wireless sensors measuring a same modality at different locations, and wherein the results of the comparing include a location of a fault in the system.