{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T23:23:26Z","timestamp":1785194606799,"version":"3.55.0"},"reference-count":122,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T00:00:00Z","timestamp":1626912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["EP\/R021031\/1"],"award-info":[{"award-number":["EP\/R021031\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>To create products that are better fit for purpose, manufacturers require new methods for gaining insights into product experience in the wild at scale. \u201cChatty Factories\u201d is a concept that explores the transformative potential of placing IoT-enabled data-driven systems at the core of design and manufacturing processes, aligned to the Industry 4.0 paradigm. In this paper, we propose a model that enables new forms of agile engineering product development via \u201cchatty\u201d products. Products relay their \u201cexperiences\u201d from the consumer world back to designers and product engineers through the mediation provided by embedded sensors, IoT, and data-driven design tools. Our model aims to identify product \u201cexperiences\u201d to support the insights into product use. To this end, we create an experiment to: (i) collect sensor data at 100 Hz sampling rate from a \u201cChatty device\u201d (device with sensors) for six common everyday activities that drive produce experience: standing, walking, sitting, dropping and picking up of the device, placing the device stationary on a side table, and a vibrating surface; (ii) pre-process and manually label the product use activity data; (iii) compare a total of four Unsupervised Machine Learning models (three classic and the fuzzy C-means algorithm) for product use activity recognition for each unique sensor; and (iv) present and discuss our findings. The empirical results demonstrate the feasibility of applying unsupervised machine learning algorithms for clustering product use activity. The highest obtained F-measure is 0.87, and MCC of 0.84, when the Fuzzy C-means algorithm is applied for clustering, outperforming the other three algorithms applied.<\/jats:p>","DOI":"10.3390\/s21154991","type":"journal-article","created":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T22:37:14Z","timestamp":1626993434000},"page":"4991","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Unsupervised Learning for Product Use Activity Recognition: An Exploratory Study of a \u201cChatty Device\u201d"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1534-4709","authenticated-orcid":false,"given":"Mike","family":"Lakoju","sequence":"first","affiliation":[{"name":"Cardiff School of Technologies, Cardiff Metropolitan University, Western Avenue, Cardiff CF5 2YB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nemitari","family":"Ajienka","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Nottingham Trent University, Nottingham NG11 8NS, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5583-7295","authenticated-orcid":false,"given":"M. Ahmadieh","family":"Khanesar","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, The University of Nottingham, University Park, Nottingham NG7 2RD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pete","family":"Burnap","sequence":"additional","affiliation":[{"name":"School of Computer Science & Informatics, Cardiff University, Wales CF10 3AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David T.","family":"Branson","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, The University of Nottingham, University Park, Nottingham NG7 2RD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"166","DOI":"10.14488\/BJOPM.2019.v16.n2.a1","article-title":"Theoretical proposal of steps for the implementation of the Industry 4.0 concept","volume":"16","author":"Cordeiro","year":"2019","journal-title":"Braz. 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