Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox

This paper studies the relevance of CWT (continuous wavelet transform) processing of vibration signals for improving the performance of CNN-based models that detect certain types of helical gearbox faults. Gear tooth damages, such as incipient and localized pitting and localized wear on helical pini...

Full description

Saved in:
Bibliographic Details
Main Authors: Iulian Lupea, Mihaiela Lupea
Format: Article
Language:English
Published: MDPI AG 2025-01-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/2/950
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832589226349166592
author Iulian Lupea
Mihaiela Lupea
author_facet Iulian Lupea
Mihaiela Lupea
author_sort Iulian Lupea
collection DOAJ
description This paper studies the relevance of CWT (continuous wavelet transform) processing of vibration signals for improving the performance of CNN-based models that detect certain types of helical gearbox faults. Gear tooth damages, such as incipient and localized pitting and localized wear on helical pinion tooth flanks, combined with improper lubrication, are the faults under observation. Vibrations at the housing level for three rotating velocities of the AC motor and three load levels (for each velocity) are acquired with a triaxial accelerometer. Through CWT, the vibration signal is decomposed into 2D time-frequency grayscale images, with a filter bank of ten voices per octave in the frequency band of interest. Three 2D-CNN-based models trained on the CWT-based representation of the vibration signals measured on individual accelerometer axes (<i>X</i>, <i>Y</i>, and <i>Z</i>) are proposed to detect the four health states (one normal and three faulty) of the helical gearbox, regardless of the selected load level or speed on the test rig. These models achieve an accuracy higher than 99%. By fusing the CWT-based representations of the signals on individual axes for use as input to a 2D-CNN, the best-performing model for the proposed defect detection task is generated, reaching an accuracy of 99.91%.
format Article
id doaj-art-eb669ab65637464da7e02b8b19aac776
institution Kabale University
issn 2076-3417
language English
publishDate 2025-01-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-eb669ab65637464da7e02b8b19aac7762025-01-24T13:21:27ZengMDPI AGApplied Sciences2076-34172025-01-0115295010.3390/app15020950Continuous Wavelet Transform and CNN for Fault Detection in a Helical GearboxIulian Lupea0Mihaiela Lupea1Faculty of Industrial Engineering, Robotics and Production Management, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, RomaniaFaculty of Mathematics and Computer Science, Babes-Bolyai University, 400084 Cluj-Napoca, RomaniaThis paper studies the relevance of CWT (continuous wavelet transform) processing of vibration signals for improving the performance of CNN-based models that detect certain types of helical gearbox faults. Gear tooth damages, such as incipient and localized pitting and localized wear on helical pinion tooth flanks, combined with improper lubrication, are the faults under observation. Vibrations at the housing level for three rotating velocities of the AC motor and three load levels (for each velocity) are acquired with a triaxial accelerometer. Through CWT, the vibration signal is decomposed into 2D time-frequency grayscale images, with a filter bank of ten voices per octave in the frequency band of interest. Three 2D-CNN-based models trained on the CWT-based representation of the vibration signals measured on individual accelerometer axes (<i>X</i>, <i>Y</i>, and <i>Z</i>) are proposed to detect the four health states (one normal and three faulty) of the helical gearbox, regardless of the selected load level or speed on the test rig. These models achieve an accuracy higher than 99%. By fusing the CWT-based representations of the signals on individual axes for use as input to a 2D-CNN, the best-performing model for the proposed defect detection task is generated, reaching an accuracy of 99.91%.https://www.mdpi.com/2076-3417/15/2/950helical gearboxcontinuous wavelet transformtriaxial accelerometer sensorvibration signalfault detectionconvolutional neural network
spellingShingle Iulian Lupea
Mihaiela Lupea
Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox
Applied Sciences
helical gearbox
continuous wavelet transform
triaxial accelerometer sensor
vibration signal
fault detection
convolutional neural network
title Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox
title_full Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox
title_fullStr Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox
title_full_unstemmed Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox
title_short Continuous Wavelet Transform and CNN for Fault Detection in a Helical Gearbox
title_sort continuous wavelet transform and cnn for fault detection in a helical gearbox
topic helical gearbox
continuous wavelet transform
triaxial accelerometer sensor
vibration signal
fault detection
convolutional neural network
url https://www.mdpi.com/2076-3417/15/2/950
work_keys_str_mv AT iulianlupea continuouswavelettransformandcnnforfaultdetectioninahelicalgearbox
AT mihaielalupea continuouswavelettransformandcnnforfaultdetectioninahelicalgearbox