Volume foliar de plantas arbóreas com sensor laser na aplicação de agrotóxico

• Autor(a) principal: Quirino, André Luís da Silva
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/785
• topic: Produtos químicos agrícolas - Aplicação; Tecnologia de aplicação; Sensor laser; Automação; Agricultural chemicals - Application; Application technology; Laser sensor; Automation; CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA

Plants measurement using the TRV method considers each plant row to be sprayed as a foliage wall, and the spraying volume should be enough to cover it. This consideration does not take into account an uneven canopy, with respect to the height, the depth and the plant foliar density. Considering the spatial variability of the plant canopy, as the height, depth and density, it becomes necessary to individualize the pesticides application on the plants crown. The LIDAR system is a remote sensing technique based on measuring the time that a laser pulse takes between its transmission and reception. The aim of this study was to evaluate the use of LMS (Laser Measurement System), 111 model, as a tool to determine, in real time, the canopy volume of woody plants in different working speed, as evaluate its performance in characterize the canopy of woody plants. First of all, it was evaluated the performance of MatLab software, as mediator of the interaction and the data transfer between the LMS and the computer, in order to represent the real environment virtually. To determine the canopy volume in real time, it was used the areas method and the convex hull methodology. Data of number of impacts in relation to the depth, the height and the width of the canopy were also extracted. The communication between the computer and the LMS was done by an Ethernet connection, which allowed data transfer in real time. The LMS was coupled to a mobile bridge, with the ability to control the working speed at a height of 0.97 m and 1.52 m from the plants row. It was used the working speed of 0.5, 1, 2, 3, 5 and 6 km h-1. This configuration was used to study the system performance, working in controlled conditions, with constant speed and predetermined route. The manual measurement of canopy volume was performed with the Whitney volume determination, also considering the canopy volume as a prolate spheroid, and the stratified height method. Generated the pattern of a simple slice measured by the LMS, the surface area perpendicular to the laser travel line was obtained by applying the surface coordinate method. With the data of the cloud of points, it was applied the convex hull function on the corresponding point of each plant to obtain its volume. It was evaluated the ability of the used method for determining the canopy height (Am) and the width (Lm) by analyzing the 3D cloud of points generated. Once the pattern of a simple slice measured by the LMS was known, the surface area perpendicular to the LMS travel line was obtained. The canopy volume was calculated by summing the volume of each simple slice, so all of the slices in the total length of the travel line were included. It was possible to use the MatLab software as a mediator of messages sending in order to configure and use the LMS. The methodology for measuring the canopy volume with the LMS was able to determine the canopy volume in real time. The measurement of canopy volume of woody plants with the LMS sensor is an important tool to save spray solution volume. The determination of canopy volume by the convex hull method is indicated when the working speed is higher than 3 km h-1. Under the conditions of this study, the LMS showed being a tool that is able to collect data from height and width of woody plants, making a less arduous procedure and reducing the need for the work to be performed manually.