Waveform Classification With Harmonic-Band Learning for Product Inspection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing non-defective product inspection methods face challenges due to individual differences in products and facilities, leading to inaccurate evaluations and decreased determination accuracy, particularly when using frequency analysis methods like FFT, which fail to account for harmonic components and noise levels.

Innovation Solution

A classification device and method that utilize a learning model to analyze time-axis waveform data, convert it into frequency characteristic data, divide it into sections, calculate maximum values, and approximate these sections to classify products based on learned data, thereby accounting for individual differences and improving accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Extent of automation

If frequency analysis methods like FFT are used for non-defective product inspection, then the inspection process can be automated, but the determination accuracy decreases due to individual differences in products and facilities

Engineering Contradiction:
Improveautomation of inspection processVSAvoiddetermination accuracy
Core Design Contradiction:
Extent of automationVSMeasurement precision

Solution Approach 1:

The patent transforms the raw vibration waveform into frequency domain data through FFT analysis, then extracts specific frequency components (harmonic components) as features. By changing the parameter representation from time-domain to frequency-domain and selecting specific frequency bands, the system achieves accurate classification despite individual differences in products and facilities

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces a learning model (classification device) as an intermediary between the vibration data and the non-defective product determination. This learning model learns the relationship between frequency characteristics and product quality from training data, enabling accurate determination while accounting for individual differences without requiring manual threshold setting

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of manufacture

If conventional frequency analysis is used, then the inspection method is simple to implement, but it fails to account for harmonic components and noise levels, reducing accuracy

Engineering Contradiction:
Improveease of implementationVSAvoidinspection accuracy
Core Design Contradiction:
Ease of manufactureVSMeasurement precision

Solution Approach 1:

The patent divides the frequency spectrum into multiple frequency bands and extracts harmonic components at different frequencies separately. By segmenting the frequency analysis into specific bands and identifying harmonic components in each band, the system captures detailed vibration characteristics that conventional methods miss, improving accuracy while maintaining implementation simplicity

Inventive Principle:
Principle #1Segmentation

Data Source

PatentUS20250290789A1Classification device, learning-model generation device, classification method, and learning-model generation method
Publication Date: 2025.09.18 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD
  • US20250290789A1 patent drawing
  • US20250290789A1 patent drawing
  • US20250290789A1 patent drawing

AI summary

A classification device includes: an acquisition unit that acquires time-axis waveform data of an object; a conversion unit that converts the time-axis waveform data into first frequency characteristic data; a spectrum calculator that divides the first frequency characteristic data into division sections by a predetermined bandwidth and calculates a maximum value of a spectrum for each of the division sections; an approximation processing unit that outputs second frequency characteristic data obtained by approximating the first frequency characteristic data on the basis of the maximum value of the spectrum for each of the division sections; a generator that generates third frequency characteristic data from the second frequency characteristic data by using a learning model; and a classification unit that classifies the object on the basis of the second frequency characteristic data and the third frequency characteristic data, in which the learning model is a model that has learned approximated learning data.