RNN Failure Prediction Using Memory Depth Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods, such as hidden Markov models and genetic algorithms, struggle to accurately predict machine failures with long inter-failure gaps, typically beyond 15 time steps, due to the vanishing or exploding gradient problem, and specialized architectures increase complexity without universal applicability.

Innovation Solution

A method using a standard Back Propagation Through Time (BPTT) trained Recurrent Neural Network (RNN) with an iterative approach to ascertain weight values for basic memory depth values, allowing for predictions across very large time gaps by relating weight values from smaller memory depth sequences, thus avoiding gradient issues.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If standard RNN with BPTT is used for machine failure prediction, then the method is simple and generalizable, but it cannot handle long inter-failure gaps due to vanishing or exploding gradient problem

Engineering Contradiction:
Improvegeneralizability of standard RNNVSAvoidprediction accuracy for long inter-failure gaps
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent segments the long inter-failure gap prediction problem into multiple smaller sub-problems by dividing the time gap into segments. Each segment is processed by the RNN separately, avoiding the need to process the entire long sequence at once. This segmentation allows the standard RNN to handle long gaps effectively by breaking down the vanishing gradient problem into manageable chunks that can be processed sequentially.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary actions by pre-processing the failure history data and preparing segmented sequences before feeding them to the RNN. The system pre-calculates and stores intermediate results for different segment lengths, which are then reused during prediction. This preliminary preparation enables the standard RNN to efficiently handle long inter-failure gaps without requiring specialized architecture modifications.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If specialized architectures are used to handle long inter-failure gaps, then prediction accuracy for long gaps improves, but device complexity increases

Engineering Contradiction:
Improveprediction accuracy for long inter-failure gapsVSAvoidcomplexity of specialized RNN architectures
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent makes the standard RNN architecture universal by demonstrating its ability to handle both short and long inter-failure gaps through the segmentation approach. The same basic RNN structure and training procedure are used regardless of the gap length, eliminating the need for different specialized architectures. This multi-functionality allows a single simple model to serve multiple prediction scenarios effectively.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the parameter of sequence length segmentation rather than modifying the fundamental RNN architecture. By adjusting how the input sequence is divided into segments and the corresponding processing parameters, the system adapts to different gap lengths using the same underlying model. This parameter-based adaptation avoids the complexity of architectural modifications while maintaining prediction accuracy.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If existing statistical or AI methods are used for short time gap prediction, then prediction is easier and more accurate, but these methods fail for long inter-failure gaps beyond 15 time steps

Engineering Contradiction:
Improveprediction accuracy for short time gapsVSAvoidprediction capability for long inter-failure gaps
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent introduces dynamics by making the segmentation strategy adaptive to the specific gap length being predicted. For shorter gaps, the system uses fewer or no segments, while for longer gaps, it automatically increases the number of segments. This dynamic adjustment allows the system to maintain high prediction accuracy across the full range of gap lengths, transitioning smoothly from short-gap to long-gap prediction modes.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS11494654B2Method for machine failure prediction using memory depth values
Publication Date: 2022.11.08 ACCENTURE GLOBAL SOLUTIONS LTD
  • US11494654B2 patent drawing
  • US11494654B2 patent drawing
  • US11494654B2 patent drawing

AI summary

Embodiments of the invention provide a method and system for machine failure prediction. The method comprises: identifying a plurality of basic memory depth values based on a composite sequence of machine failure history; ascertaining weight values for at least one of the identified basic memory depth values according to a pre-stored table which includes a plurality of mappings wherein each mapping relates a basic memory depth value to one set of weight values; and predicting a future failure using a Back Propagation Through Time (BPTT) trained Recurrent Neural Network (RNN) based on the ascertained weight values, wherein weight values related to a first basic memory depth value in the pre-stored table is ascertained based on a second set of weight values related to a second basic memory depth value which is less than the first basic memory depth value by a predetermined value.