22 research outputs found
Evaluación y análisis de la recolección del olivar por vibración
En esta tesis se aborda la mejora de las máquinas de derribo por vibración de la aceituna, que es el único método viable para la recolección mecanizada en la mayor parte de nuestro olivar. Para ello, se ha desarrollado una metodología de ensayo válida para investigación y para su transferencia a los fabricantes basada en un sistema electrónico de medida compuso por un PC portátil con una tarjeta de adquisición de datos de 32 canales y su soporte lógico para la adquisición y análisis de datos a alta velocidad, incluyendo el análisis espectral de las señales dinámica
INCLISAFE RGIS1 específico para vehículos militares
l INCLISAFE RGIS1 es un dispositivo de aviso de riesgo de vuelco para vehículos militares. Está pensado y diseñado para avisaral conductor de una situación de inestabilidad del vehículo que conduce, de modo que la señal de aviso será más insistente conforme el riesgo de vuelco aumente. Se encuentra patentado en Estados Unidos (nº 3IPDT1.0002WO). Surge a partir del INCLISAFE para vehículos agroforestales desarrollado por el G.I. AGR 126 “Mecanización y Tecnología Rural” para la empresa EGMASA (Junta de Andalucía) en colaboración con la empresa Desarrollo Tecnológico Agroindustrial (DTA
Frequency response of Valencia oranges to selective harvesting by vibration
Citrus mechanical harvesting has been investigated since the 1960’s. Even though mechanical harvesting could significantly lower production costs, the implementation by the private sector has been slow. The current harvesting technologies detach the fruits with trunk, canopy or branch vibration. For late-season sweet orange varieties which simultaneously bear mature fruit, immature fruitlets and flowers shaker harvesting decreases the subsequent year’s yield. This study, investigated the frequency response of mature fruits and immature fruitlets to determine the optimum frequency range for an efficient and selective harvest. Laboratory vibration transmission tests were conducted with 14 branches bearing 76 mature fruits and 151 immature ‘Valencia’ fruitlets. The fruit and branch response to the forced vibration was measured by several sets of five triaxial accelerometers with a dynamic signal analyser. Three frequency ranges with the highest vibration transmission values were identified for mechanical harvesting lower than 10 Hz. The first frequency range (1.5-2.5 Hz) corresponded best with the most efficient vibration transmission, involving more than 90% of fruit. The second frequency range (4.5-5 Hz) successfully discriminated between mature fruit and immature fruitlets. In this frequency range, 53.4% of mature fruit amplified the acceleration a mean value of 2.2 times, while only 7.3% of immature fruitlets amplified the acceleration with a mean value of 4.4 times. The lowest third frequency range had a vibration transmission value of 7-8 Hz. The frequency response of mature citrus fruits, and their markedly higher fruit mass, were significant factors in efficient selective mechanical harvesting
Effects of an integrated harvest system on the quality of olive fruit for small producers
Small producers confront specific challenges when they opt to produce high-quality olive fruit. Limited resources for investing in harvest machinery and manpower are the main reasons for continuing a traditional harvest method that puts the final product and its economic value at risk. This paper discusses the efficiency of an integrated harvest system as a possible solution to these specific challenges. The system is formed by a newly designed manual harvesting device and the use of a cooling room near the olive grove. Both systems were evaluated to assess their feasibility for optimum conditions before processing. The combined effect of the harvesting method and cold storage on the fruit characteristics (incidence of decay, skin color, weight loss, firmness, respiration, and ethylene production) was evaluated on three different varieties (‘Arbequina’, ‘Picual’ and ‘Verdial’) and four different storage times (0, 4, 8, and 14 days). The results indicate that the proposed harvesting method in combination with an appropriate cooling system offers an affordable alternative for obtaining fruit with the best physiological characteristics.Efectos de un sistema integrado de recolección para pequeños productores en la calidad de la aceituna recogida. Los pequeños productores se enfrentan a retos específicos, cuando optan por producir aceitunas de alta calidad. La imposibilidad económica de invertir, tanto en maquinaria de cosecha, como en mano de obra es la razón principal que obliga a continuar una recolección tradicio-nal que pone en riesgo el producto final y su valor económico. Este estudio analiza la eficiencia de un sistema de recolección integrado como una posible solución a estos desafíos específicos. El sistema está formado por un dispositivo de recogida manual de nuevo diseño y el uso de una cámara de frío en la finca. El efecto combinado del método de recolección presentado y el almacenamiento en frío sobre las características de la fruta (incidencia de podredumbre, color de piel, pérdida de peso, firmeza, respiración y producción de etileno) se evaluó en tres variedades diferentes (‘Arbequina’, ‘Picual’ y ‘ Verdial’) y diferentes tiempos de almacenamiento (0, 4, 8, 14 días). Los re-sultados indican que la combinación de un método de recolección mecánica y un sistema de enfriamiento adecuado ofrece una alternativa económicamente asequible para obtener frutos con las mejores características fisiológicas.Spanish Ministry of Science and Innovation AGL2015-71585-
Assessment of Spray Deposit and Loss in Traditional and Intensive Olive Orchards with Conventional and Crop-Adapted Sprayers
Plant protection product (PPP) applications to isolated olive trees are commonly performed with regular air-assisted sprayers, which are not adapted to their particular characteristics. Whilst strong efforts have been undertaken over the last years to improve technical aspects like canopy detection and automated proportional dosing, nearly no efforts have been made regarding the sprayer adaption to the crop. For this reason, three prototype sprayers were developed for traditional and intensive olive cultivations systems (P1: centrifugal fan; P2: six small side axial fans; P3: two axial fans in tower structure) with the purpose to improve the application efficiency. The main goal of the present study was to check spray quality and efficiency in comparison with the conventional sprayer in both cultivation systems. The sprayers were tested in two different olive groves and properly calibrated according to the tree dimensions. The spray deposition, coverage, drift, and losses to the ground were measured in five trees per cultivation system by placing the appropriate collectors. The sprayers performed very differently in both cultivation systems. In the intensive system, the spray deposition did not present significant differences (p = 0.105). However, it did in the traditional system (p = 0.003), with P3 obtaining the best results. The spray coverage followed the same trend, with significant differences only in the traditional orchard (p = 0.011), with the prototypes leading. The conventional equipment generated the highest spray losses in both cultivation systems. Crop adapted spraying can significantly improve the spray quality and efficiency in difficult crops like olive. This topic may have a key importance to match the environmentally sustainable use of PPP
Olive Crown Porosity Measurement Based on Radiation Transmittance: An Assessment of Pruning Effect
Crown porosity influences radiation interception, air movement through the fruit orchard,
spray penetration, and harvesting operation in fruit crops. The aim of the present study was to develop
an accurate and reliable methodology based on transmitted radiation measurements to assess the
porosity of traditional olive trees under different pruning treatments. Transmitted radiation was
employed as an indirect method to measure crown porosity in two olive orchards of the Picual
and Hojiblanca cultivars. Additionally, three different pruning treatments were considered to
determine if the pruning system influences crown porosity. This study evaluated the accuracy
and repeatability of four algorithms in measuring crown porosity under different solar zenith angles.
From a 14 to 30 solar zenith angle, the selected algorithm produced an absolute error of less
than 5% and a repeatability higher than 0.9. The described method and selected algorithm proved
satisfactory in field results, making it possible to measure crown porosity at different solar zenith
angles. However, pruning fresh weight did not show any relationship with crown porosity due
to the great differences between removed branches. A robust and accurate algorithm was selected
for crown porosity measurements in traditional olive trees, making it possible to discern between
different pruning treatments
Development of a Telemetry and Yield-Mapping System of Olive Harvester
Sensors, communication systems and geo-reference units are required to achieve
an optimized management of agricultural inputs with respect to the economic and
environmental aspects of olive groves. In this study, three commercial olive harvesters
were tracked during two harvesting seasons in Spain and Chile using remote and autonomous
equipment that was developed to determine their time efficiency and effective based on
canopy shaking for fruit detachment. These harvesters work in intensive/high-density (HD)
and super-high-density (SHD) olive orchards. A GNSS (Global Navigation Satellite System)
and GSM (Global System for Mobile Communications) device was installed to track these
harvesters. The GNSS receiver did not affect the driver’s work schedule. Time elements
methodology was adapted to the remote data acquisition system. The effective field
capacity and field efficiency were investigated. In addition, the field shape, row length,
angle between headland alley and row, and row alley width were measured to determinate
the optimum orchard design parameters value. The SHD olive harvester showed significant
lower effective field capacity values when alley width was less than 4 m. In addition, a
yield monitor was developed and installed on a traditional olive harvester to obtain a yield
map from the harvested area. The hedge straddle harvester stood out for its highly effective
field capacity; nevertheless, a higher field efficiency was provided by a non-integral lateral canopy shaker. All of the measured orchard parameters have influenced machinery yields,
whether effective field capacity or field efficiency. A saving of 40% in effective field
capacity was achieved with a reduction from 4 m or higher to 3.5 m in alley width for SHD
olive harvester. A yield map was plotted using data that were acquired by a yield monitor,
reflecting the yield gradient in spite of the larger differences between tree yield
Methodology for Olive Pruning Windrow Assessment Using 3D Time-of-Flight Camera
The management of olive pruning residue has shifted from burning to shredding, laying residues on soil, or harvesting residues for use as a derivative. The objective of this research is to develop, test, and validate a methodology to measure the dimensions, outline, and bulk volume of pruning residue windrows in olive orchards using both a manual and a 3D Time-of-Flight (ToF) camera. Trees were pruned using trunk shaker targeted pruning, from which two different branch sizes were selected to build two separate windrow treatments with the same pruning residue dose. Four windrows were built for each treatment, and four sampling points were selected along each windrow to take measurements using both manual and 3D ToF measurements. Windrow section outline could be defined using a polynomial or a triangular function, although manual measurement required processing with a polynomial function, especially for high windrow volumes. Different branch sizes provided to be significant differences for polynomial function coefficients, while no significant differences were found for windrow width. Bigger branches provided less bulk volume, which implied that these branches formed less porous windrows that smaller ones. Finally, manual and 3D ToF camera measurements were validated, giving an adequate performance for olive pruning residue windrow in-field assessment
The mock up as a learning tool for developing agricultural machinery
Se propone la introducción de un ejercicio basado en proyectos en la asignatura de “Diseño de maquinaria agraria. Automática agraria”. Para resolver el problema los alumnos han de pasar por todas las fases de las metodologías de desarrollo de productos: búsqueda de información, planificación del trabajo, diseño, cálculo, fabricación, etc. Al final, los alumnos deberán obtener una maqueta que modele el trabajo de una máquina agrícola con funciones cargadora o manipuladora. Los alumnos eligieron una metodología de trabajo en grupo por ingeniería secuencial, en lugar de la aconsejada por ingeniería concurrente, dado que requiere menor interacción entre ellos, pero al final del ejercicio expusieron los problemas encontrados habiendo aprendido de los pros y contras de ambas. Los indicadores finales de la práctica muestran la mejora de la calidad docente con mayor participación del alumnado y con mejores resultados académicos. Sin embargo, se requiere del profesorado una dedicación y tiempo extra en la asignatura, así como mayores recursos, por lo que en el futuro se debería intentar la coordinación de la práctica con otras materias similares o con cursos de formación permanente.An exercise based on project is proposed in lesson “Agricultural machinery design. Automation”. To solve the problem, students must go through all phases of product development methodologies: information search, work planning, design, calculation, manufacturing…Finally, they must obtain a model which simulates the work performed by a agricultural machinery with loader or manipulator functions. This year, the students chose a methodology of work sequentially, instead of the one recommended, concurrent engineering. This choice required less interaction among them but at the end they exposed the cons and pros of using it. The teaching indicator show improvement of the quality of the teaching with greater participation of students, and better academic results. However, teachers are required an extra dedication and time, as well as more resources. So, in the future should be coordinated the practice with other similar subjects or extra courses
Assessment of aerial and underground vibration transmission in mechanically trunk shaken olive trees
The present study analyses the transmission of vibrations generated from a multidirectional trunk shaker to olive tree structure considering both the aerial zone (trunk and branches) and the underground zone (the coarse root). The vibration characterization was conducted by measuring acceleration on several points of the tree during harvesting operations. The influence of two different heights of shaker head clamping was analysed. In addition, a dynamic probing was performed in order to evaluate soil compaction. The results showed that the vibration performed by the trunk shaker head, corresponding to an acceleration resultant of approximately 77 ms–2 with a dominant vibration frequency of 18 Hz, increased up to 106% in branches and decreased up to 90% in trunks. At root level, where the analysis was carried out at 1/3 and 2/3 of the coarse root length, the acceleration values diminished significantly to 17 ms–2 and 12 ms–2, respectively. Soil dynamic resistance was lower (36 kg cm–2) near the trees than between the trees (53 kg cm–2). The vibration transmission to the aerial and the underground parts diversely influences the dynamic behaviour of the olive tree, considering an operational frequency of a commercial trunk shaker. The assessment of vibration transmission to the aerial part could contribute to improve fruit detachment and reduce branch breaking and leaf detachment. While vibration transmission to the underground part rises new challenges considering soil compaction in olive groves