{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T18:55:17Z","timestamp":1768416917469,"version":"3.49.0"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2012,11,9]],"date-time":"2012-11-09T00:00:00Z","timestamp":1352419200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This research demonstrates the basic elements of a prototype automated orchard sprayer which delivers pesticide spray selectively with respect to the characteristics of the targets. The density of an apple tree canopy was detected by PROWAVE 400EP250 ultrasound sensors controlled by a Cypress PSOC CY8C29466 microcontroller. The ultrasound signal was processed with an embedded computer built around a LPC1343 microcontroller and fed in real time to electro-magnetic valves which open\/close spraying nozzles in relation to the canopy structure. The analysis focuses on the detection of appropriate thresholds on 15 cm ultrasound bands, which correspond to maximal response to tree density, and this was selected for accurate spraying guidance. Evaluation of the system was performed in an apple orchard by detecting deposits of tartrazine dye (TD) on apple leaves. The employment of programmable microcontrollers and electro-magnetic valves decreased the amount of spray delivered by up to 48.15%. In contrast, the reduction of TD was only up to 37.7% at some positions within the tree crown and 65.1% in the gaps between trees. For all these reasons, this concept of precise orchard spraying can contribute to a reduction of costs and environmental pollution, while obtaining similar or even better leaf deposits.<\/jats:p>","DOI":"10.3390\/s121115500","type":"journal-article","created":{"date-parts":[[2012,11,9]],"date-time":"2012-11-09T11:18:29Z","timestamp":1352459909000},"page":"15500-15519","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Programmable Ultrasonic Sensing System for Targeted Spraying in Orchards"],"prefix":"10.3390","volume":"12","author":[{"given":"Denis","family":"Stajnko","sequence":"first","affiliation":[{"name":"Faculty of Agriculture and Life Sciences, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Berk","sequence":"additional","affiliation":[{"name":"Faculty of Agriculture and Life Sciences, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mario","family":"Le\u0161nik","sequence":"additional","affiliation":[{"name":"Faculty of Agriculture and Life Sciences, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Viktor","family":"Jej\u010di\u010d","sequence":"additional","affiliation":[{"name":"Agricultural Institute of Slovenia, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miran","family":"Lakota","sequence":"additional","affiliation":[{"name":"Faculty of Agriculture and Life Sciences, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrej","family":"\u0160trancar","sequence":"additional","affiliation":[{"name":"Faculty of Computer and Information Science, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marko","family":"Ho\u010devar","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jurij","family":"Rakun","sequence":"additional","affiliation":[{"name":"Faculty of Agriculture and Life Sciences, University of Maribor, 2000 Maribor, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,11,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/S0261-2194(00)00046-6","article-title":"Spray deposits and losses in different sized apple trees from an axial fan orchard sprayer: 1. Effects of spray liquid flow rate","volume":"20","author":"Cross","year":"2001","journal-title":"Crop Prot."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1094\/PD-72-0629","article-title":"Evaluation Of the tree-row-volume model for full-season pesticide application on apples","volume":"72","author":"Sutton","year":"1988","journal-title":"Plant Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1016\/j.biosystemseng.2006.08.004","article-title":"An electronic control system for pesticide application proportional to the canopy width of tree crops","volume":"95","author":"Solanelles","year":"2006","journal-title":"Biosyst. Eng."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1117\/12.144035","article-title":"Application of smart submunition technology to agribusiness","volume":"1836","author":"Wangler","year":"1993","journal-title":"SPIE Proc."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1006\/bioe.2002.0082","article-title":"Comparison of different spray volume deposition models using Lidar measurements of apple orchards","volume":"82","author":"Walklate","year":"2002","journal-title":"Biosyst. Eng."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"999","DOI":"10.1243\/095440705X34667","article-title":"Hough-transform-based vision algorithm for crop row detection of an automated agricultural vehicle","volume":"219","author":"Zhang","year":"2005","journal-title":"Proc. Inst. Mech. Eng. D: J. Automob. Eng."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1287","DOI":"10.1016\/j.cropro.2006.11.003","article-title":"Variable rate application of plant protection products in vineyard using ultrasonic sensors","volume":"26","author":"Gil","year":"2007","journal-title":"Crop Prot."},{"key":"ref_8","first-page":"85","article-title":"Electronic measurement of tree row volume","volume":"1","author":"McConnell","year":"1983","journal-title":"Agric. Electron."},{"key":"ref_9","first-page":"35","article-title":"Pesticide loss reduction by automatic adoption of spraying on globular trees","volume":"78","year":"2001","journal-title":"J. Agric. Eng. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1016\/j.cropro.2009.12.022","article-title":"Variable rate dosing in precision viticulture: Use of electronic devices to improve application efficiency","volume":"29","author":"Llorens","year":"2010","journal-title":"Crop Prot."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"367","DOI":"10.13031\/2013.8587","article-title":"Investigation of laser and ultrasonic ranging sensors for measurements of citrus canopy volume","volume":"18","author":"Tumbo","year":"2002","journal-title":"Appl. Eng. Agric."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2459","DOI":"10.3390\/s110302459","article-title":"Performance of an ultrasonic ranging sensor in apple tree canopies","volume":"11","author":"Planas","year":"2011","journal-title":"Sensors"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"173","DOI":"10.13031\/2013.15887","article-title":"Effects of foliage density and ground speed on ultrasonic measurement of citrus tree volume","volume":"20","author":"Zaman","year":"2004","journal-title":"Appl. Eng. Agric."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/j.compag.2010.11.007","article-title":"Evaluation of ultrasonic sensor for variable-rate spray applications","volume":"75","author":"Jeon","year":"2011","journal-title":"Comput. Electron. Agric."},{"key":"ref_15","unstructured":"SparkFun Electronics Available online: http:\/\/www.sparkfun.com\/products\/8687 (accessed on 20 May 2012)."},{"key":"ref_16","unstructured":"The MathWorks Inc. (2011). MATLAB Version 7.12, The MathWorks Inc."},{"key":"ref_17","first-page":"587","article-title":"Design and testing of an ultrasound system for targeted spraying in orchards","volume":"57","author":"Stajnko","year":"2011","journal-title":"J. Mech. Eng."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/S0261-2194(96)00054-3","article-title":"Foliar deposition and pesticide losses from three air-assisted sprayers in a hedgerow vineyard","volume":"16","author":"Pergher","year":"1997","journal-title":"Crop Prot."},{"key":"ref_19","first-page":"1","article-title":"Pesticide dose adjustment in vineyard spraying and potential for dose reduction","volume":"X","author":"Pergher","year":"2008","journal-title":"Agr. Eng. Int. CIGR J."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"787","DOI":"10.13031\/2013.6240","article-title":"Recovery rate of the tracer days used for spray deposit assessment","volume":"44","author":"Pergher","year":"2001","journal-title":"Trans. ASABE"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.cropro.2006.04.002","article-title":"Dosage of plant protection products adapted to leaf area index in viticulture","volume":"26","author":"Siegfried","year":"2007","journal-title":"Crop Prot."},{"key":"ref_22","first-page":"357","article-title":"Sensor equipped orchard spraying\u2014Efficacy, savings and drift reduction","volume":"57","author":"Koch","year":"2000","journal-title":"Aspects Appl. Biol."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/11\/15500\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:53:27Z","timestamp":1760219607000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/11\/15500"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,11,9]]},"references-count":22,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2012,11]]}},"alternative-id":["s121115500"],"URL":"https:\/\/doi.org\/10.3390\/s121115500","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,11,9]]}}}