Process Anomaly Diagnosis Using Hierarchical Color Maps

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In manufacturing processes like iron steel, diagnosing anomalies is challenging due to high variance and complex phenomena, leading to noise in prediction accuracy when using statistical models, making it difficult to distinguish true anomalies from noise.

Innovation Solution

A process anomalous state diagnostic device that uses a hierarchical matrix structure for color mapping and displays deviation indices over time, allowing for easy recognition of true anomalies by visualizing temporal changes in color maps and scatter diagrams.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If comprehensive determination with a large number of statistical models is performed, then the diagnostic coverage is improved, but the noise in prediction accuracy increases making it difficult to determine true anomalies

Engineering Contradiction:
Improvediagnostic coverageVSAvoidprediction accuracy
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The patent segments the large number of statistical models into multiple groups based on their prediction accuracy characteristics. By dividing the models into groups (e.g., high-accuracy group, medium-accuracy group, low-accuracy group), the system can selectively apply different evaluation strategies to each group, thereby maintaining comprehensive diagnostic coverage while reducing the noise impact from low-accuracy models on the overall prediction result.

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If variance in prediction accuracy among statistical models is reduced, then the noise is decreased, but the ability to handle complex manufacturing processes with high variance is limited

Engineering Contradiction:
Improveprediction accuracy consistencyVSAvoidprocess complexity handling
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent applies local quality by evaluating and weighting different statistical models based on their local performance characteristics. Each model is assessed individually for its prediction accuracy and reliability, and weights are assigned accordingly. This allows high-accuracy models to have greater influence on the final diagnosis while low-accuracy models contribute less, thereby reducing noise without limiting the system's ability to handle complex processes with diverse characteristics.

Inventive Principle:
Principle #3Local quality

3Ease of operation

If a hierarchical matrix structure with multiple layers is used for color mapping, then the visual recognition of anomalies is improved, but the device complexity increases

Engineering Contradiction:
Improveanomaly recognition easeVSAvoidcolor mapping structure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The patent introduces a hierarchical dimension to the color mapping structure by organizing statistical models and their prediction results into multiple layers. The first layer provides an overview of all models, while subsequent layers provide progressively more detailed information. This dimensional organization allows operators to navigate from general to specific anomaly information systematically, improving visual recognition without requiring an overly complex flat structure.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP3644152B1Process abnormal state diagnosing device and abnormal state diagnosing method
Publication Date: 2024.10.23 JFE STEEL CORP
  • EP3644152B1 patent drawingFigure 1
  • EP3644152B1 patent drawingFigure 2
  • EP3644152B1 patent drawingFigure 3

AI summary

An anomalous state diagnostic device 1A diagnoses an anomalous state of a process based on a plurality of deviation indexes for the magnitude of deviation from a reference that is the normal state of the process, and includes: a color mapping unit 64 configured to configure a two-dimensional matrix that has a first axis as an axis of a temporal factor including time and that has a second axis as an axis of an item of each deviation index, associate each cell of the matrix with data for an item of the deviation index and a temporal factor, and allocate a color in accordance with the magnitude of the deviation index to each cell of the matrix; and a color map display unit 65 configured to display a color map produced by the color mapping unit.