{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T12:02:24Z","timestamp":1774008144875,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T00:00:00Z","timestamp":1773964800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Siemens Mobility GmbH"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, the task of detecting bearing faults in railway vehicles during regular operation by analyzing acoustic (airborne sound) data is addressed. To that end, various features are studied, among which the Mel Frequency Cepstral Coefficients (MFCCs) are best suited for detecting bearing faults by analyzing airborne sound. The MFCCs are used to train a Multi-Layer Perceptron (MLP) classifier. The proposed method is evaluated with real-world data for a state-of-the-art commuter railway vehicle in a dedicated measurement campaign. Classification results demonstrate that the chosen MFCC features allow for reliable detection of bearing damages, even for damages that were not included in training.<\/jats:p>","DOI":"10.3390\/s26061947","type":"journal-article","created":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T09:44:41Z","timestamp":1773999881000},"page":"1947","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Real-World Airborne Sound Analysis for Health Monitoring of Bearings in Railway Vehicles"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-9419-5917","authenticated-orcid":false,"given":"Matthias","family":"Kreuzer","sequence":"first","affiliation":[{"name":"Multimedia Communications and Signal Processing, Friedrich-Alexander-Universit\u00e4t Erlangen\u2013N\u00fcrnberg (FAU), 91058 Erlangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6564-8907","authenticated-orcid":false,"given":"David","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Siemens Mobility GmbH, 90441 N\u00fcrnberg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-8973-3494","authenticated-orcid":false,"given":"Simon","family":"Wokusch","sequence":"additional","affiliation":[{"name":"Siemens Mobility GmbH, 90441 N\u00fcrnberg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6501-3174","authenticated-orcid":false,"given":"Walter","family":"Kellermann","sequence":"additional","affiliation":[{"name":"Multimedia Communications and Signal Processing, Friedrich-Alexander-Universit\u00e4t Erlangen\u2013N\u00fcrnberg (FAU), 91058 Erlangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1016\/j.ymssp.2010.07.017","article-title":"Rolling element bearing diagnostics\u2014A tutorial","volume":"25","author":"Randall","year":"2011","journal-title":"Mech. 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