{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T19:09:22Z","timestamp":1775848162598,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,4,26]],"date-time":"2019-04-26T00:00:00Z","timestamp":1556236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/linproxy.fan.workers.dev:443\/https\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["DPI2017-89827-R"],"award-info":[{"award-number":["DPI2017-89827-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["BES-2015-071698"],"award-info":[{"award-number":["BES-2015-071698"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2014-59229-R"],"award-info":[{"award-number":["TEC2014-59229-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["H2020-780262-SHARE4RARE"],"award-info":[{"award-number":["H2020-780262-SHARE4RARE"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]},{"name":"ACCI\u00d2","award":["INNOTECRD18-1-0054"],"award-info":[{"award-number":["INNOTECRD18-1-0054"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper proposes the application of a low-cost gas sensor array in an assistant personal robot (APR) in order to extend the capabilities of the mobile robot as an early gas leak detector for safety purposes. The gas sensor array is composed of 16 low-cost metal-oxide (MOX) gas sensors, which are continuously in operation. The mobile robot was modified to keep the gas sensor array always switched on, even in the case of battery recharge. The gas sensor array provides 16 individual gas measurements and one output that is a cumulative summary of all measurements, used as an overall indicator of a gas concentration change. The results of preliminary experiments were used to train a partial least squares discriminant analysis (PLS-DA) classifier with air, ethanol, and acetone as output classes. Then, the mobile robot gas leak detection capabilities were experimentally evaluated in a public facility, by forcing the evaporation of (1) ethanol, (2) acetone, and (3) ethanol and acetone at different locations. The positive results obtained in different operation conditions over the course of one month confirmed the early detection capabilities of the proposed mobile system. For example, the APR was able to detect a gas leak produced inside a closed room from the external corridor due to small leakages under the door induced by the forced ventilation system of the building. <\/jats:p>","DOI":"10.3390\/s19091957","type":"journal-article","created":{"date-parts":[[2019,4,26]],"date-time":"2019-04-26T02:04:13Z","timestamp":1556244253000},"page":"1957","update-policy":"https:\/\/linproxy.fan.workers.dev:443\/https\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":69,"title":["Application of an Array of Metal-Oxide Semiconductor Gas Sensors in an Assistant Personal Robot for Early Gas Leak Detection"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/linproxy.fan.workers.dev:443\/https\/orcid.org\/0000-0001-8210-3262","authenticated-orcid":false,"given":"Jordi","family":"Palac\u00edn","sequence":"first","affiliation":[{"name":"Universitat de Lleida, Jaume II, 69, 25001 Lleida, Spain"}]},{"given":"David","family":"Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Universitat de Lleida, Jaume II, 69, 25001 Lleida, Spain"}]},{"given":"Eduard","family":"Clotet","sequence":"additional","affiliation":[{"name":"Universitat de Lleida, Jaume II, 69, 25001 Lleida, Spain"}]},{"given":"Tom\u00e0s","family":"Pallej\u00e0","sequence":"additional","affiliation":[{"name":"Universitat de Lleida, Jaume II, 69, 25001 Lleida, Spain"}]},{"ORCID":"https:\/\/linproxy.fan.workers.dev:443\/https\/orcid.org\/0000-0002-7327-6396","authenticated-orcid":false,"given":"Javier","family":"Burgu\u00e9s","sequence":"additional","affiliation":[{"name":"Department of Electronics and Biomedical Engineering, Universitat de Barcelona, Marti i Franqu\u00e9s 1, 08028 Barcelona, Spain"},{"name":"Signal and Information Processing for Sensing Systems, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10\u201312, 08028 Barcelona, Spain"}]},{"ORCID":"https:\/\/linproxy.fan.workers.dev:443\/https\/orcid.org\/0000-0001-8854-8588","authenticated-orcid":false,"given":"Jordi","family":"Fonollosa","sequence":"additional","affiliation":[{"name":"Centre de Recerca en Enginyeria Biom\u00e8dica, CREB. Enginyeria de Sistemes, Autom\u00e0tica i Inform\u00e0tica Industrial, Universitat Polit\u00e8cnica de Catalunya, 08028 Barcelona, Spain"},{"name":"Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine CIBER-BBN, 28029 Madrid, Spain"},{"name":"Institut de Recerca Pedi\u00e0trica Hospital Sant Joan de D\u00e9u, 08950 Esplugues de Llobregat, Spain"}]},{"ORCID":"https:\/\/linproxy.fan.workers.dev:443\/https\/orcid.org\/0000-0003-4369-544X","authenticated-orcid":false,"given":"Antonio","family":"Pardo","sequence":"additional","affiliation":[{"name":"Department of Electronics and Biomedical Engineering, Universitat de Barcelona, Marti i Franqu\u00e9s 1, 08028 Barcelona, Spain"}]},{"ORCID":"https:\/\/linproxy.fan.workers.dev:443\/https\/orcid.org\/0000-0003-2663-2965","authenticated-orcid":false,"given":"Santiago","family":"Marco","sequence":"additional","affiliation":[{"name":"Department of Electronics and Biomedical Engineering, Universitat de Barcelona, Marti i Franqu\u00e9s 1, 08028 Barcelona, Spain"},{"name":"Signal and Information Processing for Sensing Systems, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10\u201312, 08028 Barcelona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6045","DOI":"10.3390\/s140406045","article-title":"Ambient intelligence application based on environmental measurements performed with an assistant mobile robot","volume":"14","author":"Martinez","year":"2014","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Palac\u00edn, J., Clotet, E., Mart\u00ednez, D., Moreno, J., and Tresanchez, M. 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