Field Operation Planning for Agricultural Vehicles: A Hierarchical Modeling Framework

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Field Operation Planning for Agricultural Vehicles: A Hierarchical Modeling Framework. Manuscript PM 06 021. Vol. IX. February, 2007

Optimal Dynamic Motion Sequence Generation for Multiple Harvesters

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Optimal Dynamic Motion Sequence Generation for Multiple Harvesters. Manuscript ATOE 07 001. Vol. IX. July, 2007

Analysis of the detachment of citrus fruits by vibration using artificial vision

The vibratory behaviour of citrus fruits is studied using slow-motion cameras in order to gain a better understanding of the parameters involved in fruit detachment when mechanical harvesting is done using shakers. Single citrus fruits with a small portion of stem were vibrated using strokes from 60 mm to 180 mm and frequencies from 3 Hz to 18 Hz. The movement was recorded at 300 fps and the main parameters considered for fruit detachment were determined through the analysis of the video sequences. Image-processing algorithms created for this purpose were applied to the automated estimation of the centroid of the fruit, the angle of the stem pistil axis, and the position of some selected points in the fruit in each frame of the video sequences to obtain dynamic parameters such as the position, speed and acceleration of the fruit during the movement until it is detached. The signals obtained from the image processing were filtered, providing results in accordance with the calibration systems. In general, results suggest that the inertial forces transmitted to the fruit were lower than the tensile forces required to detach the fruit by pulling it in the stem pistil direction. The largest peaks were observed using long strokes that required fewer cycles for detachment. On the other hand, short strokes combined with high frequencies needed more cycles, and thus a fatigue phenomenon was present. Short strokes and low frequencies were unable to detach some fruit. (C) 2014 IAgrE. Published by Elsevier Ltd. All rights reserved.This work was founded by the Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA) through the projects RTA2009-00118-C02-01 and RTA2009-00118-C02-02, and co-founded by European FEDER founds.Torregrosa Mira, A.; Albert Gil, FE.; Aleixos Borrás, MN.; Ortiz Sánchez, MC.; Blasco Ivars, J. (2014). Analysis of the detachment of citrus fruits by vibration using artificial vision. Biosystems Engineering. 119:1-12. https://doi.org/10.1016/j.biosystemseng.2013.12.010S11211

Energy flow for integrated apple production in Greece

Integrated production requires constant improvement of methods employed to achieve high fruit quality and yield with minimal inputs. This work was undertaken to evaluate the energy inputs for apple production, to identify the highest energy consuming operations and propose ways to improve them. Integrated production methods were employed during 1999 and 2000 at 26 apple (Malus domestica Borkh.) orchards in Zagora Pelion (Central Greece). The inputs and outputs of major nutrients (only five farms) as well as energy were calculated and mean values are presented. N inputs were five times higher than outputs and reduction in N fertilization can be considered. Total energy inputs were 50.7 GJ ha(-1) and outputs 118.5 GJ ha(-1) (51.6 GJ ha(-1) from fruit). Chemicals (pesticides, fertilizers), use of machinery and fuel were the most important inputs for apple production, while human labor, although intensively used, accounted for small energy inputs due to conversion factor used. Energy outputs could be improved, as the potential for fruit production is higher compared to fruit production of the study years. Energy productivity was calculated (average of the 2 years) as 0.42 kg MJ(-1), energy intensity as 2.50 MJ kg(-1) and energy efficiency (only fruit considered) as 1.0. Thus, energy savings could be obtained without significant yield reduction, mainly through reducing fertilizer inputs (especially N), diminishing pest control applications through proper techniques and improving the farm road network. (c) 2006 Elsevier B.V. All rights reserved