Measurement of spray drift with a specifically designed lidar system

Field measurements of spray drift are usually carried out by passive collectors and tracers. However, these methods are labour- and time-intensive and only provide point- and time-integrated measurements. Unlike these methods, the light detection and ranging (lidar) technique allows real-time measurements, obtaining information with temporal and spatial resolution. Recently, the authors have developed the first eye-safe lidar system specifically designed for spray drift monitoring. This prototype is based on a 1534 erbium-doped glass laser and an 80 mm diameter telescope, has scanning capability, and is easily transportable. This paper presents the results of the first experimental campaign carried out with this instrument. High coefficient of determination (R2>0.85) were observed by comparing lidar measurements of the spray drift with those obtained by horizontal collectors. Furthermore, the lidar system allowed an assessment of the drift reduction potential (DRP) when comparing low-drift nozzles with standard ones, resulting in a DRP of 57%(preliminaryresult) for the tested nozzles. The lidar system was also used for monitoring the evolution of the spray flux over the canopy and to generate 2-D images of these plumes. The developed instrument is an advantageous alternative to passive collectors and opens the possibility of new methods for field measurement of spray drift.Peer ReviewedPostprint (published version

Real-time tree foliage surface estimation using a ground laser scanner.

The optimization of most pesticide and fertilizer applications is based on overall grove conditions. In this paper, we propose a measurement system to estimate the foliage surface of a tree crop. The system is based on a ground laser scanner that estimates the volume of the trees and then extrapolates their leaf area using simple and fast algorithms to allow true real-time operation. Tests with pear trees demonstrated that the relation between the volume and the foliage can be interpreted as linear with a coefficient of correlation (R) of 0.81, and the foliage surface can be estimated from this volume with an average error less than 6%.Postprint (published version

Real-Time tree foliage estimation using a ground laser scanner

Postprint (published version

First results of a non destructive LIDAR system for the characterisation of tree crops as a support for the optimisation of pesticide treatments

Preprin

Idoneidad y manejo de los datos de un escáner láser (LIDAR) para la caracterización de determinados parámetros vegetativos de interés en frutales y viña

Preprin

Innovative LIDAR 3D Dynamic Measurement System to Estimate Fruit-Tree Leaf Area

In this work, a LIDAR-based 3D Dynamic Measurement System is presented and evaluated for the geometric characterization of tree crops. Using this measurement system, trees were scanned from two opposing sides to obtain two three-dimensional point clouds. After registration of the point clouds, a simple and easily obtainable parameter is the number of impacts received by the scanned vegetation. The work in this study is based on the hypothesis of the existence of a linear relationship between the number of impacts of the LIDAR sensor laser beam on the vegetation and the tree leaf area. Tests performed under laboratory conditions using an ornamental tree and, subsequently, in a pear tree orchard demonstrate the correct operation of the measurement system presented in this paper. The results from both the laboratory and field tests confirm the initial hypothesis and the 3D Dynamic Measurement System is validated in field operation. This opens the door to new lines of research centred on the geometric characterization of tree crops in the field of agriculture and, more specifically, in precision fruit growing

Review. Precision Viticulture.: Research topics, challengesand opportunities in site-specific vineyard management

Precision Viticulture (PV) is a concept that is beginning to have an impact on the wine-growing sector. Its practical implementation is dependant on various technological developments: crop sensors and yield monitors, local and remote sensors, Global Positioning Systems (GPS), VRA (Variable-Rate Application) equipment and machinery, Geographic Information Systems (GIS) and systems for data analysis and interpretation. This paper reviews a number of research lines related to PV. These areas of research have focused on four very specific fields: 1) quantification and evaluation of within-field variability, 2) delineation of zones of differential treatment at parcel level, based on the analysis and interpretation of this variability, 3) development of Variable-Rate Technologies (VRT) and, finally, 4) evaluation of the opportunities for site-specific vineyard management. Research in these fields should allow winegrowers and enologists to know and understand why yield variability exists within the same parcel, what the causes of this variability are, how the yield and its quality are interrelated and, if spatial variability exists, whether site-specific vineyard management is justifiable on a technical and economic basis.La Viticultura de Precisión (VP) es un concepto que empieza a tener un cierto impacto en el sector vitivinícola. Su implementación práctica está ligada al desarrollo de cierta tecnología: sensores y monitores de cosecha, sensores locales y remotos, Sistemas de Posicionamiento Global (SPG), equipos y maquinaria de aplicación variable, Sistemas de Información Geográfica (SIG) y sistemas para el análisis y la interpretación de la información. En este trabajo se ha llevado a cabo una revisión de las diferentes líneas de investigación relacionadas con la VP. Dichas áreas de investigación se han centrado en cuatro ámbitos muy concretos: 1) cuantificación y evaluación de la variabilidad intraparcelaria, 2) delimitación a nivel de parcela de zonas de tratamiento diferencial, en base al análisis y la interpretación de dicha variabilidad, 3) desarrollo de tecnologías para la actuación variable en campo (variable-rate technologies, VRT) y, finalmente, 4) evaluación de la oportunidad del manejo sitio-específico en viticultura. La investigación en estos ámbitos debe permitir a viticultores y enólogos conocer y comprender por qué la cosecha varía dentro de una misma parcela, cúales son las causas de dicha variación, cómo están interrelacionadas la cosecha y su calidad y, ante la existencia de variabilidad espacial, si está justificado técnica y económicamente el manejo diferencial de los viñedos

Lidar: towards a new methodology for field measurement of spray drift

Lidar technology is becoming a promising alternative for spray drift measurement to the labour and time-expensive methodologies based on the ISO 22866 standard. This paper presents last advancements in an eye-safe lidar system specifically designed for drift monitoring. The lidar system was tested with an air-assisted sprayer in two cases: with standard hollow cone and air induction low-drift nozzles. The remaining variables (flow rate, environmental conditions,…) were similar. Lidar measurements allowed to know the time evolution of spray drift clouds and showed a much higher droplet concentration, dwelling time and dimensions for the cloud generated by standard nozzles. Also, the ability of the lidar system to distinguish different nozzle types according to their drift potential was proved. Finally, staring (laser beam stationary through the drift cloud) and 2D scanning measurements are discussed as starting points for an alternative spray drift measurement methodology

Ground laser scanner data analysis for Leaf Area Index (LAI) prediction in orchards and vineyards.

Preprin