Root Cause Analysis Using Granger Causality for Failure Onset

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional root cause analysis of mechanical system failures often fails to accurately identify the onset of failures due to the propagation of malfunctions, requiring human expertise and being inefficient in determining Granger causalities between time series data variables.

Innovation Solution

A system employing a greedy hill climbing process to perform a polynomial number of conditional independence tests to determine Granger causality between variables from time series data, facilitating autonomous root cause analysis and onset detection in mechanical systems.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional analyses are used to identify root cause, then human expertise can fix the system after failure, but it is impossible to accurately identify when the root cause initiated

Engineering Contradiction:
Improveaccuracy of identifying root cause onset timeVSAvoiddelay between root cause event and system failure
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by performing Granger causality analysis on time series data to identify potential root causes and their onset times before actual system failure occurs. The system continuously monitors variables and detects causal relationships that precede failures, enabling early intervention rather than post-failure analysis by human experts.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent replaces the mechanical system of human expert analysis with an automated computational system that uses Granger causality tests and greedy hill climbing algorithms to identify root causes and their onset times. This substitution enables precise temporal identification of root causes that was previously impossible for human experts.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If exhaustive causal discovery algorithms are used to determine Granger causality, then complete causal relationships can be identified, but the computational complexity becomes exponential

Engineering Contradiction:
Improvecompleteness of causal relationship identificationVSAvoidcomputational complexity of causal discovery algorithm
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies segmentation by dividing the causal discovery process into manageable components: (1) selecting candidate variables, (2) performing greedy hill climbing to identify parent variables, (3) conducting conditional independence tests, and (4) determining Granger causality. This segmentation reduces the problem from exponential complexity to polynomial complexity while maintaining reliability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent uses partial action by implementing a greedy hill climbing approach that performs conditional independence tests only for necessary variable pairs rather than all possible combinations. This partial testing strategy reduces computational complexity from exponential to polynomial while still identifying the essential causal relationships needed for root cause analysis.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentUS11816178B2Root cause analysis using granger causality
Publication Date: 2023.11.14 INTERNATIONAL BUSINESS MACHINE CORPORATION
  • US11816178B2 patent drawing
  • US11816178B2 patent drawing
  • US11816178B2 patent drawing

AI summary

Techniques regarding root cause analyses based on time series data are provided. For example, one or more embodiments described herein can comprise a system, which can comprise a memory that can store computer executable components. The system can also comprise a processor, operably coupled to the memory, and that can execute the computer executable components stored in the memory. The computer executable components can comprise maintenance component that can detect a cause of failure for a mechanical system by employing a greedy hill climbing process to perform a polynomial number of conditional independence tests to determine a Granger causality between variables from time series data of the mechanical system given a conditioning set.