Method and system of machine fault classification using label-consistent convolutional dictionary learning
Existing Convolutional Dictionary Learning (CDL) based machine fault classification do not utilize label information while learning the dictionary, hence the representation learned are not class-discriminative. Method and system disclosed herein provide a label-consistent convolutional dictionary learning approach for machine fault classification. The approach involves generating a training data for a classifier, wherein coefficients forming a plurality of class-discriminative features form the training data. The training data is then used to train a classifier, which is then used to perform machine fault classification for a given test data.
1 . A processor implemented method, comprising:
receiving, via one or more hardware processors, a training sensor data (S) and a set of classification labels (Q) associated with the training sensor data, as input data;
performing, via the one or more hardware processors, a joint optimization on the input data to learn a plurality of parameters comprising a) one or more dictionary atoms {D m }, one or more coefficients {X m } associated with each of the one or more dictionary atoms, and weights {W m } associated with a label consistency term for each of the one or more coefficients for m th filter in a sequence of filters, wherein performing the joint optimization comprises iteratively updating the parameters {D m }, {X m }, and {W m }, till an objective function represented in the joint optimization is converged, wherein a plurality of class-discriminative dictionaries are learnt for each of a plurality of filters, by performing the joint optimization, wherein the joint optimization is represented as
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where, Q∈R C×K represents one hot encoded classification labels for C-classes, and K is the total number of training samples;
generating, via the one or more hardware processors, a plurality of coefficients forming a plurality of class-discriminative features, from the plurality of learnt class-discriminative dictionaries and the training sensor data (S); concatenating, via the one or more hardware processors, the plurality of coefficients of the plurality of filters to obtain a concatenated matrix of coefficients wherein the concatenated matrix of coefficients form a training data for a classifier, wherein the classifier is trained using the concatenated matrix of coefficients forming the plurality of class-discriminative features and the set of classification labels; and
using, via the one or more hardware processors, the trained classifier for performing machine fault classification.
2 . The method of claim 1 , wherein performing the joint optimization comprises:
learning one or more coefficients of each of the plurality of filters based on the training sensor data, the set of classification labels and a dictionary comprising the plurality of filters, and weights associated with a label consistency term comprising the plurality of filters;
learning one or more weights associated with a label consistency term of each of the plurality of filters based on the set of classification labels and the coefficients ({X m }) comprising the plurality of filters; and
learning the one or more dictionary atoms of each of the plurality of filters, based on the training sensor data and the coefficients comprising the plurality of filters.
3 . The method of claim 1 , wherein the classifier is used for classification of test data, comprising:
obtaining a test input comprising a test sensor data;
computing a plurality of test coefficients for each of the plurality of filters, using the test sensor data and learnt dictionary associated with each of the plurality of filters;
concatenating the plurality of test coefficients of the plurality of filters to obtain a concatenated matrix of test coefficients; and
estimating a set of output labels for the test sensor data using the concatenated matrix of test coefficients and the trained classifier.
4 . The method of claim 1 , wherein the training sensor data comprises one of a time series data and an image data.
5 . A system, comprising:
one or more hardware processors;
a communication interface; and
a memory storing a plurality of instructions, wherein the plurality of instructions cause the one or more hardware processors to:
receive a training sensor data (S) and a set of classification labels (Q) associated with the training sensor data, as input data;
perform a joint optimization on the input data to learn a plurality of parameters comprising a) one or more dictionary atoms {D m }, one or more coefficients {X m } associated with each of the one or more dictionary atoms, and weights {W m } associated with a label consistency term for each of the one or more coefficients for m th filter in a sequence of filters, wherein performing the joint optimization comprises iteratively updating the parameters {D m }, {X m }, and {W m }, till an objective function represented in the joint optimization is converged, wherein a plurality of class-discriminative dictionaries are learnt for each of a plurality of filters, by performing the joint optimization, wherein the joint optimization is represented as
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min
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D
m
}
{
X
m
}
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}
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2
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=
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where, Q∈R C×K represents one hot encoded classification labels for C-classes, and K is the total number of training samples;
generate a plurality of coefficients forming a plurality of class-discriminative features, from the plurality of learnt class-discriminative dictionaries and the training sensor data (S);
concatenate the plurality of coefficients of the plurality of filters to obtain a concatenated matrix of coefficients wherein the concatenated matrix of coefficients form a training data for a classifier, wherein the classifier is trained using the concatenated matrix of coefficients forming the plurality of class-discriminative features and the set of classification labels; and
use the trained classifier for performing machine fault classification.
6 . The system of claim 5 , wherein the one or more hardware processors are configured to perform the joint optimization by:
learning one or more coefficients of each of the plurality of filters based on the training sensor data, the set of classification labels and a dictionary comprising the plurality of filters, and weights associated with a label consistency term comprising the plurality of filters;
learning one or more weights associated with a label consistency term of each of the plurality of filters based on the set of classification labels and the coefficients ({X m }) comprising the plurality of filters; and
learning the one or more dictionary atoms of each of the plurality of filters, based on the training sensor data and the coefficients comprising the plurality of filters.
7 . The system of claim 5 , wherein the one or more hardware processors are configured to use the classifier for classification of test data, by:
obtaining a test input comprising a test sensor data;
computing a plurality of test coefficients for each of the plurality of filters, using the test sensor data and learnt dictionary associated with each of the plurality of filters;
concatenating the plurality of test coefficients of the plurality of filters to obtain a concatenated matrix of test coefficients; and
estimating a set of output labels for the test sensor data using the concatenated matrix of test coefficients and the trained classifier.
8 . The system of claim 5 , wherein the training sensor data comprises one of a time series data and an image data.
9 . One or more non-transitory machine-readable information storage mediums comprising one or more instructions which when executed by one or more hardware processors cause:
receiving a training sensor data (S) and a set of classification labels (Q) associated with the training sensor data, as input data;
performing, via the one or more hardware processors, a joint optimization on the input data to learn a plurality of parameters comprising a) one or more dictionary atoms {D m }, one or more coefficients {X m } associated with each of the one or more dictionary atoms, and weights {W m } associated with a label consistency term for each of the one or more coefficients for m th filter in a sequence of filters, wherein performing the joint optimization comprises iteratively updating the parameters {D m }, {X m }, and {W m }, till an objective function represented in the joint optimization is converged, wherein a plurality of class-discriminative dictionaries are learnt for each of a plurality of filters, by performing the joint optimization, wherein the joint optimization is represented as
arg
min
{
D
m
}
{
X
m
}
{
W
m
}
1
2
∑
m
=
1
M
D
m
X
m
-
S
F
2
+
λ
∑
m
=
1
M
X
m
1
+
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Q
-
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m
=
1
M
W
m
X
m
F
2
s
.
t
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m
2
=
1
∀
m
,
where, Q∈R C×K represents one hot encoded classification labels for C-classes, and K is the total number of training samples;
generating a plurality of coefficients forming a plurality of class-discriminative features, from the plurality of learnt class-discriminative dictionaries and the training sensor data (S);
concatenating the plurality of coefficients of the plurality of filters to obtain a concatenated matrix of coefficients wherein the concatenated matrix of coefficients form a training data for a classifier, wherein the classifier is trained using the concatenated matrix of coefficients forming the plurality of class-discriminative features and the set of classification labels; and
using the trained classifier for performing machine fault classification.
10 . The one or more non-transitory machine-readable information storage mediums of claim 9 , wherein performing the joint optimization comprises:
learning one or more coefficients of each of the plurality of filters based on the training sensor data, the set of classification labels and a dictionary comprising the plurality of filters, and weights associated with a label consistency term comprising the plurality of filters;
learning one or more weights associated with a label consistency term of each of the plurality of filters based on the set of classification labels and the coefficients ({X m }) comprising the plurality of filters; and
learning the one or more dictionary atoms of each of the plurality of filters, based on the training sensor data and the coefficients comprising the plurality of filters.
11 . The one or more non-transitory machine-readable information storage mediums of claim 9 , wherein the one or more instructions which when executed by the one or more hardware processors cause the classifier to perform classification of test data, by:
obtaining a test input comprising a test sensor data;
computing a plurality of test coefficients for each of the plurality of filters, using the test sensor data and learnt dictionary associated with each of the plurality of filters;
concatenating the plurality of test coefficients of the plurality of filters to obtain a concatenated matrix of test coefficients; and
estimating a set of output labels for the test sensor data using the concatenated matrix of test coefficients and the trained classifier.
12 . The one or more non-transitory machine-readable information storage mediums of claim 9 , wherein the training sensor data comprises one of a time series data and an image data.