{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T16:47:53Z","timestamp":1778258873005,"version":"3.51.4"},"reference-count":82,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2020,8,21]],"date-time":"2020-08-21T00:00:00Z","timestamp":1597968000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014132","name":"European Metrology Programme for Innovation and Research","doi-asserted-by":"publisher","award":["17IND02"],"award-info":[{"award-number":["17IND02"]}],"id":[{"id":"10.13039\/100014132","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>IoT systems based on collaborative sensor networks are becoming increasingly common in various industries owing to the increased availability of low-cost sensors. The quality of the data provided by these sensors may be unknown. For these reasons, advanced data processing and sensor network self-calibration methods have become popular research topics. In terms of metrology, the self-calibration methods lack the traceability to the established measurement standards of National Metrology Institutes (NMIs) through an unbroken chain-link of calibration. This problem can be solved by the ongoing digitalization of the metrology infrastructure. We propose a conceptual solution based on Digital Calibration Certificates (DCCs), Digital SI (D-SI), and cryptographic digital identifiers, for validation of data quality and trustworthiness. The data that enable validation and traceability can be used to improve analytics, decision-making, and security in industrial applications. We discuss the applicability and benefits of our solutions in a selection of industrial use cases, where collaborative sensing has already been introduced. We present the remaining challenges in the digitization and standardization processes regarding digital metrology and the future work required to address them.<\/jats:p>","DOI":"10.3390\/s20174730","type":"journal-article","created":{"date-parts":[[2020,8,21]],"date-time":"2020-08-21T09:21:51Z","timestamp":1598001711000},"page":"4730","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Metrological Challenges in Collaborative Sensing: Applicability of Digital Calibration Certificates"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4249-5705","authenticated-orcid":false,"given":"Tuukka","family":"Mustap\u00e4\u00e4","sequence":"first","affiliation":[{"name":"School of Engineering, Aalto University, 02150 Espoo, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2941-9545","authenticated-orcid":false,"given":"Pekka","family":"Nikander","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Aalto University, 02150 Espoo, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9095-0063","authenticated-orcid":false,"given":"Daniel","family":"Hutzschenreuter","sequence":"additional","affiliation":[{"name":"Physikalisch-Technische Bundesanstalt (PTB), Division 1\u2013Mechanics and Acoustics, 38116 Braunschweig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1672-1921","authenticated-orcid":false,"given":"Raine","family":"Viitala","sequence":"additional","affiliation":[{"name":"School of Engineering, Aalto University, 02150 Espoo, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1016\/j.adhoc.2019.01.008","article-title":"Self-calibration methods for uncontrolled environments in sensor networks: A reference survey","volume":"88","author":"Doudou","year":"2019","journal-title":"Ad Hoc Netw."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1193","DOI":"10.1109\/ACCESS.2019.2950507","article-title":"A Feature-Based Framework for Structuring Industrial Digital Twins","volume":"8","author":"Autiosalo","year":"2020","journal-title":"IEEE Access"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1515\/teme-2019-0073","article-title":"Metrologie f\u00fcr heterogene Sensornetzwerke und Industrie 4.0","volume":"86","author":"Ludwig","year":"2019","journal-title":"tm Tech. 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