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1.
Design and testing of an ultrasound system for targeted spraying in orchards
Denis Stajnko, Marko Hočevar, Tone Godeša, Mario Lešnik, Andrej Štrancar, Brane Širok, Viktor Jejčič, Aleš Malneršič, 2011, original scientific article

Abstract: The research aims to demonstrate the basic system elements of a prototype automated orchard sprayer, which can deliver pesticide spray selectively withrespect to the characteristics of the targets. The contour of the apple tree canopy was detected by ultra sound sensors Prowave 400EP14D and appropriate electronics. Ultra sound signal was processed by a personal computer and fed in real-time to spraying nozzles which open and close in relation to the canopy structure. The current project focuses on developing the system components for spraying an individual tree. The evaluation was performed in field experiments by detecting deposits on leaves and water sensitive papers (WSP). The demonstrated concept of precise application of pesticide sprays supports a decrease in the amount of delivered spray, thereby reducing both costs and environmental pollution by plant protection products.
Keywords: pršilniki, ultrazvok, razporeditev škropiva, sadovnjaki, air-assisted sprayer, ultra sound, algorithm, spray distribution, orchard
Published: 10.07.2015; Views: 382; Downloads: 12
URL Full text (0,00 KB)

2.
Programmable ultrasonic sensing system for targeted spraying in orchards
Denis Stajnko, Peter Berk, Mario Lešnik, Viktor Jejčič, Miran Lakota, Andrej Štrancar, Marko Hočevar, Jurij Rakun, 2012, original scientific article

Abstract: 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. Evaluationof 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 amountof spray delivered by up to 48.15%. In contrast, the reduction of TD wasonly 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.
Keywords: air-assisted sprayer, ultrasound, algorithm, programmable, microcontroller, spray distribution, orchard
Published: 22.06.2017; Views: 283; Downloads: 24
.pdf Full text (890,30 KB)

3.
DOLOČANJE ODMERKA FITOFARMACEVTSKEGA SREDSTVA Z UPORABO MEHKEGA ODLOČITVENEGA MODELA
Peter Berk, 2018, doctoral dissertation

Abstract: Pri procesu nanašanja fitofarmacevtskega sredstva, pomešanega z vodo (škropilna brozga) v predpisani koncentraciji, s klasičnimi pršilniki za kemično varstvo krošenj dreves v sadovnjaku se uporabljajo standardni modeli za izražanje odmerkov fitofarmacevtskega sredstva in se pri tem ne upoštevajo karakteristične lastnosti krošenj dreves v sadovnjaku. Rezultat takšnih modelov je nekontrolirano krmiljenje količine škropilne brozge skozi posamezne šobe na krošnjo drevesa. V doktorski disertaciji predstavljamo avtonomni sistem, ki omogoča nadzorovano krmiljenje količin brozge skozi šobe na različnih segmentih krošnje drevesa. Avtonomni sistem temelji na mehkem odločitvenem modelu, v katerega smo, zaradi preciznejšega krmiljenja količin brozge, vključili informacijo o ocenjeni vrednosti listne površine. Ocenjeno vrednost listne površine na segmentih krošnje drevesa smo ovrednotili na osnovi ročnih meritev, laserskega merilnega sistema in programskega algoritma, s katerim smo omogočili tridimenzionalno rekonstrukcijo krošnje drevesa. V eksperimentu v sadovnjaku smo za ovrednotenje listne površine zajeli različne starosti in sorte jablan ('zlati delišes', 'jonagold' in 'gala'). Z uporabo regresijske metode smo ocenili zvezo med dvema odvisnima spremenljivkama (digitalno število zadetkov odbitih laserskih žarkov in digitalna prostornina krošnje drevesa) in eno neodvisno spremenljivko (listna površina, ročno izmerjena). Glede na razmerje med številom oblakov točk in listne površine smo ugotovili, da znaša maksimalna vrednost korelacijskega koeficienta 0,878. Sestavni del mehkega odločitvenega modela je predstavljal mehki logični algoritem za krmiljenje tripoložajnih elektromagnetnih ventilov v pulznoširinskem načinu, ki smo jih namestili na prototip aksialnega pršilnika. Rezultati so pokazali, da lahko z mehkim odločitvenim modelom omogočimo krmiljenje količin škropilne brozge v točno določenem območju glede na ocenjeno vrednost listne površine, zato bo ta model v bližnji prihodnosti predstavljal močno orodje pri zmanjševanju porabe fitofarmacevtskih sredstev za varstvo rastlin.
Keywords: fitofarmacevtsko sredstvo, merjenje, krmiljenje, algoritem, krošnja drevesa
Published: 26.07.2018; Views: 175; Downloads: 17
.pdf Full text (12,84 MB)

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