Quality control engine for complex physical systems

Patent metadata

Field	Value
Publication number	US-2016154802-A1
Application number	US-201514956352-A
Country	US
Kind code	A1
Filing date	Dec 1, 2015
Priority date	Dec 2, 2014
Publication date	Jun 2, 2016
Grant date	—

Abstract

Systems and methods for quality control for physical systems, including a quality control engine for transforming raw time series data collected from each of a plurality of sensors in the physical system into one or more sets of feature series by extracting features from the raw time series. Feature ranking scores are generated for each of the sensors by ranking each of the features using an ensemble of feature rankers, and fused importance scores are generated by aggregating the feature ranking scores for each of the sensors and combining ranking scores from each ranker in the ensemble. System quality is controlled by identifying sensors responsible for quality degradation based on the fused importance scores.

First claim

What is claimed is:

1 . A method for quality control for a physical system, comprising:
transforming raw time series data collected from each of a plurality of sensors in the physical system into one or more sets of feature series by extracting features from the raw time series; generating feature ranking scores for each of the sensors by ranking each of the features using an ensemble of feature rankers; generating fused importance scores by aggregating the feature ranking scores for each of the sensors and combining ranking scores from each ranker in the ensemble; and controlling system quality by identifying sensors responsible for quality degradation based on the fused importance scores.

2 . The method as recited in claim 1 , wherein the ensemble of feature rankers considers a plurality of aspects of feature interactions and their dependencies to generate the feature ranking scores for each of the sensors.

3 . The method as recited in claim 1 , wherein the ensemble of feature rankers includes at least one of a regularization-based ranker, a tree-based ranker, or a nonlinear ranker.

4 . The method as recited in claim 1 , wherein the physical system is a physical manufacturing system.

5 . The method as recited in claim 1 , wherein a sliding window technique is employed during the transforming to extract the features while preserving continuity along a time axis.

6 . The method as recited in claim 1 , wherein the features are stored in a pre-defined library, the library including a plurality of feature definitions describing different aspects of signal dynamics.

7 . The method as recited in claim 6 , wherein the different aspects include at least one of characteristics of time series in a temporal domain, characteristics of time series in a frequency domain, temporal dependencies of individual time series, or temporal dependencies across different time series.

8 . The method as recited in claim 1 , wherein the feature ranking scores are normalized using a sigmoid function before generating the fused importance scores.

9 . A quality control engine for a physical system, comprising:
a time series transformer for transforming raw time series data collected from each of a plurality of sensors in the physical system into one or more sets of feature series by extracting features from the raw time series; an ensemble of feature rankers configured to rank each of the features to generate feature ranking scores for each of the sensors; a combiner for generating fused importance scores by aggregating the feature ranking scores for each of the sensors and fusing ranking scores from each ranker in the ensemble; and a controller for managing system quality by identifying sensors responsible for quality degradation based on the fused importance scores.

10 . The system as recited in claim 9 , wherein the ensemble of feature rankers considers a plurality of aspects of feature interactions and their dependencies to generate the feature ranking scores for each of the sensors.

11 . The system as recited in claim 9 , wherein the ensemble of feature rankers includes at least one of a regularization-based ranker, a tree-based ranker, or a nonlinear ranker.

12 . The system as recited in claim 9 , wherein the physical system is a physical manufacturing system.

13 . The system as recited in claim 9 , wherein a sliding window technique is employed during the transforming to extract the features while preserving continuity along a time axis.

14 . The system as recited in claim 9 , wherein the features are stored in a pre-defined library, the library including a plurality of feature definitions describing different aspects of signal dynamics.

15 . The system as recited in claim 14 , wherein the different aspects include at least one of characteristics of time series in a temporal domain, characteristics of time series in a frequency domain, temporal dependencies of individual time series, or temporal dependencies across different time series.

16 . The system as recited in claim 9 , wherein the feature ranking scores are normalized using a sigmoid function before generating the fused importance scores.

17 . A computer-readable storage medium including a computer-readable program, wherein the computer-readable program when executed on a computer causes the computer to perform the steps of:
transforming raw time series data collected from each of a plurality of sensors in the physical system into one or more sets of feature series by extracting features from the raw time series; generating feature ranking scores for each of the sensors by ranking each of the features using an ensemble of feature rankers; generating fused importance scores by aggregating the feature ranking scores for each of the sensors and combining ranking scores from each ranker in the ensemble; and controlling system quality by identifying sensors responsible for quality degradation based on the fused importance scores.

18 . The computer-readable storage medium as recited in claim 17 , wherein the ensemble of feature rankers considers a plurality of aspects of feature interactions and their dependencies to generate the feature ranking scores for each of the sensors

19 . The computer-readable storage medium as recited in claim 17 , wherein the ensemble of feature rankers includes at least one of a regularization-based ranker, a tree-based ranker, or a nonlinear ranker.

20 . The computer-readable storage medium as recited in claim 17 , wherein a sliding window technique is employed during the transforming to extract the features while preserving continuity along a time axis.

Assignees

• Nec Lab America Inc

Inventors

• Yan Tan
• Jiang Guofei
• Chen Haifeng
• Takehiko Mizoguchi

Classifications

• G05B2219/32179

  Quality control, monitor production tool with multiple sensors · CPC title

• G05B19/4184 Primary

  characterised by fault tolerance, reliability of production system · CPC title

• G06F17/30551

  Physics · mapped topic

• G06F17/30554

  Physics · mapped topic

• G06F17/3053 Primary

  Physics · mapped topic