{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T17:09:03Z","timestamp":1774804143710,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,8,26]],"date-time":"2021-08-26T00:00:00Z","timestamp":1629936000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Electronics"],"abstract":"<jats:p>The automation of agricultural processes is expected to positively impact the environment by reducing waste and increasing food security, maximising resource use. Precision spraying is a method used to reduce the losses during pesticides application, reducing chemical residues in the soil. In this work, we developed a smart and novel electric sprayer that can be assembled on a robot. The sprayer has a crop perception system that calculates the leaf density based on a support vector machine (SVM) classifier using image histograms (local binary pattern (LBP), vegetation index, average, and hue). This density can then be used as a reference value to feed a controller that determines the air flow, the water rate, and the water density of the sprayer. This perception system was developed and tested with a created dataset available to the scientific community and represents a significant contribution. The results of the leaf density classifier show an accuracy score that varies between 80% and 85%. The conducted tests prove that the solution has the potential to increase the spraying accuracy and precision.<\/jats:p>","DOI":"10.3390\/electronics10172061","type":"journal-article","created":{"date-parts":[[2021,8,26]],"date-time":"2021-08-26T09:27:57Z","timestamp":1629970077000},"page":"2061","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["Smarter Robotic Sprayer System for Precision Agriculture"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4047-1395","authenticated-orcid":false,"given":"Andr\u00e9 Rodrigues","family":"Baltazar","sequence":"first","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, 4200-465 Porto, Portugal"},{"name":"ECT\u2014School of Sciences and Technologies, UTAD\u2014University of Tr\u00e1s-os-Montes and Alto Douro, 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8486-6113","authenticated-orcid":false,"given":"Filipe Neves dos","family":"Santos","sequence":"additional","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8573-3147","authenticated-orcid":false,"given":"Ant\u00f3nio Paulo","family":"Moreira","sequence":"additional","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, 4200-465 Porto, Portugal"},{"name":"FEUP\u2014Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5798-1298","authenticated-orcid":false,"given":"Ant\u00f3nio","family":"Valente","sequence":"additional","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, 4200-465 Porto, Portugal"},{"name":"ECT\u2014School of Sciences and Technologies, UTAD\u2014University of Tr\u00e1s-os-Montes and Alto Douro, 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8406-0064","authenticated-orcid":false,"given":"Jos\u00e9 Boaventura","family":"Cunha","sequence":"additional","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, 4200-465 Porto, Portugal"},{"name":"ECT\u2014School of Sciences and Technologies, UTAD\u2014University of Tr\u00e1s-os-Montes and Alto Douro, 5000-801 Vila Real, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1007\/s10846-016-0340-5","article-title":"Towards a Reliable Robot for Steep Slope Vineyards Monitoring","volume":"83","author":"Sobreira","year":"2016","journal-title":"J. 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