Trajectory tracking is one of the key technologies for tractor automatic navigation. Its main purpose is to adjust the steering mechanism of the tractor to follow the planned trajectory. Thus, in ...this paper a trajectory tracking control system is designed for an agricultural tractor with the electric power steering mechanism. A DC brush motor is added on the steering column of the tractor and the hardware circuits for the steering controller are designed to control the front wheel angel. The three degrees of freedom model of the tractor is established, and a trajectory tracking control system is proposed including a fuzzy sliding mode controller and a steering angle tracking controller designed according to the internal mode control and minimized sensitivity theory. The effectiveness of the designed trajectory tracking control system is demonstrated by simulation analyses in reference to the planed trajectory.
Research on autonomous driving technology is actively underway to solve the facing problems in the agricultural field. Combine harvesters used in East Asian countries, including Korea, are ...tracked-type vehicles. The steering control system of the tracked vehicle has different characteristics from the wheeled vehicle used in the agricultural tractor. In this paper, a dual GPS antenna-based autonomous driving system and path tracking algorithm were developed for a robot combine harvester. An α-turn-type work path generation algorithm and a path tracking algorithm were developed. The developed system and algorithm were verified through experiments using actual combine harvesters. The experiment consisted of an experiment with harvesting work and an experiment without harvesting work. In the experiment without harvesting work, an error of 0.052 m occurred during working driving and 0.207 m during turning driving. In the experiment where the harvesting work was carried out, an error of 0.038 m occurred during work driving and 0.195 m during turning driving. As a result of comparing the non-work area and driving time to the results of manual driving, the self-driving experiment with harvesting work showed an efficiency of 76.7%.
The current multi-row planter always leads to uneven seeding spacing between rows while seeding in curve paths, which causes uneven growth, a cost increase of production and management, and reduced ...yield. With the development of smart farming technology, a curve seeding compensation and precise positioning model is proposed in the paper to calculate the real-time speed and position of each seeding unit based on the information from multisensors, such as GNSS and IMU, and to predict the next seeding position to achieve uniform seeding on the curve and improve the unit yield of crops. MATLAB Simulink simulation experiments show that the seeding pass rate of the model is 99.97% when the positioning accuracy is ±0.01 m and the traction speed is 1 m/s, and the seeding pass rate of the five-row seeder is as high as 99.81% when the traction speed is 3 m/s, which verifies the effectiveness and practicality of the model.
In recent years, operations research in agriculture has improved the harvested yield, reduced the cost and time required for field operations, and maintained economic and environmental ...sustainability. The heuristics method, named Evolutionary neighborhood discovery algorithm (ENDA), is applied to minimize the inter-field and intra-field distance of the routing planning of machines in multiple agricultural fields. The problem is an extended version of the Agricultural Routing Planning (ARP) that takes into consideration the different capacity of the machines and multiple agricultural fields. This research also describes the mathematical model to represent the proposed problem formulated as an integer program. The experimental results show that ENDA successfully solves ARP instances, giving the best results and the fastest running time compared to those obtained by Genetic Algorithms and Tabu Search. The results also show that ENDA can save an average of 11.72% of the distance traveled by the machines outside the working path (when making maneuvers, going to or from the entrances and going from and returning to the Depot).
•Driver self-reported passing was related with perception of others’ passing behavior.•FE experienced males had higher odds of passing FE than non-experienced males.•FE experienced females had lower ...odds of passing FE than non-experienced females.•Among experienced FE drivers, males had higher odds of passing FE than females.
Crashes involving farm equipment (FE) are a major safety concern for farmers as well as all other users of the public road system in both rural and urban areas. These crashes often involve passenger vehicle drivers striking the farm equipment from behind or attempting to pass, but little is known about drivers’ perceived norms and self-reported passing behaviors. The objective of this study is to examine factors influencing drivers' farm equipment passing frequencies and their perceptions about the passing behaviors of other drivers.
Data were collected via intercept surveys with adult drivers at local gas stations in two small rural towns in Iowa. The survey asked drivers about their demographic information, frequency of passing farm equipment, and perceptions of other drivers' passing behavior in their community and state when approaching farm equipment (proximal and distal descriptive norms). A multinomial logistic regression model was used to estimate the relationship between descriptive norms and self-reported passing behavior.
Survey data from 201 adult drivers showed that only 10% of respondents considered farm equipment crashes to be a top road safety concern. Respondents who perceived others passing farm equipment frequently in their community were more likely to report that they also frequently pass farm equipment. The results also showed interactions between gender and experience operating farm equipment in terms of self-reported passing behavior.
Results from this study suggest local and state-level norms and perceptions of those norms may be important targets for intervention to improve individual driving behaviors around farm equipment.
With the gradual increase in the annual production of citrus, the efficiency of human labor has become the bottleneck limiting production. To achieve an unmanned citrus picking technology, the ...detection accuracy, prediction speed, and lightweight deployment of the model are important issues. Traditional object detection methods often fail to achieve balanced effects in all aspects. Therefore, an improved YOLOv7 network model is proposed, which introduces a small object detection layer, lightweight convolution, and a CBAM (Convolutional Block Attention Module) attention mechanism to achieve multi-scale feature extraction and fusion and reduce the number of parameters of the model. The performance of the model was tested on the test set of citrus fruit. The average accuracy (mAP
) reached 97.29%, the average prediction time was 69.38 ms, and the number of parameters and computation costs were reduced by 11.21 M and 28.71 G compared with the original YOLOv7. At the same time, the Citrus-YOLOv7 model's results show that it performs better compared with the current state-of-the-art network models. Therefore, the proposed Citrus-YOLOv7 model can contribute to solving the problem of citrus detection.
The area grown with processing potato crops in the Argentinian Pampas has been increasing steadily since 1995. The aim of this work was to assess the effects of N, P and S upon yield and tuber ...quality and their impact on CO.sub.2 emissions assessed with the Cool Farm Tool-Potato. During the spring-summer growing seasons 2008/2009 and 2009/2010, ten fertilization experiments to individually assess N, P and S effects were carried out in the southeast region of the Argentinian Pampas. Nitrogen (four N rates), phosphorus (four P rates) and sulfur (three S rates) were applied at planting and tuber initiation; at combined rates of 0, 50, 100 and 150 kg N ha.sup.-1, and at rates of 0, 25, 50 and 100 kg P ha.sup.-1 and 0, 10 and 20 kg S ha.sup.-1. N and P had a positive effect on total tuber yield, but tuber dry matter concentration (DMC) decreased at higher N rates. The fraction of marketable tubers suitable for processing into French fries increased with the addition of N, showed no variations with P fertilization, and decreased when S was applied. French fry colour, length/width (L:W) ratio and tuber defects were not affected by N, P and S fertilization. With regard to CO.sub.2 emissions assessed with the Cool Farm Tool-Potato, results showed that the higher the N rates the higher the CO.sub.2 emissions, but they decreased at higher yields. P and S rates did not have an impact on the CO.sub.2 emissions, which also decreased at higher yields. Under the production system of the Pampas, N should be split between planting and tuber initiation, and intermediate P rates should be applied all at planting, in order to improve crop yield and quality and to reduce CO.sub.2 emissions.
Sampling plans are an essential part of integrated pest management programs. Sequential sampling plans enable rapid and low-cost assessment of pest densities. Thrips are emerging pests in soybean ...crops, and the main method used in pest control is chemical. In soybean crops, insecticides are applied mainly using tractors or airplanes. Thus, this work aimed to determine sequential sampling plans for thrips in soybean crops with insecticide applications using a tractor or airplane. Data were collected in 56 soybean fields, and each field was 20 ha. Sampling plans were determined and validated. The lower (m0) and upper (m1) limits of the sequential sampling plans were: m0 = 1.72 and m1 = 3.43 (by tractor applications) and, m0 = 2.27 and m1 = 4.53 thrips. sample–1 (by airplane applications). The slope (S) and the lower (h0) and upper (h1) intercepts of the sequential sampling plans were: S = 2.42, h0 = –5.79, and h1 = 5.79 (by tractor applications) and, S = 3.19, h0 = –6.83, and h1 = 6.83 (by airplane applications). Sequential sampling plans allowed for correct decisions to be made in all situations using a maximum of 10 samples. The sequential plan reduced the sampling effort by over 87% compared to conventional sampling plans. Therefore, these control decision-making systems have proven feasible and advantageous for implementing integrated pest management programs for controlling thrips species in soybean crops. Graphical Abstract
This paper is about the performance of the base-cutter BONEM blades in the sugar cane harvester machine CASE-IH 7000, by means of a flaw analysis and experimental field test in real condition of work ...by mass loss method, for determination of the tools wear. As fundamental results, it was obtained that the base cutter blades are responsible for more than 50% of the system flaw and that the magnitude of the wear during 48 hours of working period provokes that the tool losses its total capacity of work.
The present work was developed with the objective of analyzing work efficiency indicators of agricultural aggregates formed with a YTO x1204 tractor, harrows and a land plane, in order to establish ...them partially for the future planning of agricultural works in the Agroindustrial Company of Grains "Fernando Echenique" from Granma Province. To carry out the research, Cuban standards were used as well as instructions and methodologies referred on specialized literature. The results showed that most of the values of the efficiency indicators of these agricultural groups are below the technical possibilities. However, the utilization coefficient of the working width (epsilonbeta) for the land plane, the utilization coefficient of the working speed (epsilonV) of the 52-disc heavy harrow and the utilization coefficient of work shift (tau) of the three aggregates are classified as acceptable. It is concluded that the magnitudes of real productivity (Wr) obtained behaved below the real possibilities of the set with magnitudes of 14.65; 17.71 and 29.1 ha shift.sup.-1, respectively, which is due to violations of the kinematic parameters during work. Keywords: Working Width, Working Speed, Working Depth, Shift Time and Productivity. El presente trabajo se desarrollo con el objetivo de analizar mediante el calculo de indicadores de eficiencia del trabajo de los agregados agricolas formados con tractor YTO x1204, gradas y alisador, estableciendo de forma parcial estos para la planificacion futura de los trabajos agricolas en la Empresa Agroindustrial de Granos Fernando Echenique de la provincia Granma. Para la realizacion de la investigacion se utilizaron las normas cubanas. Tambien se tuvieron en cuenta las instrucciones y metodologias expuestas por libros sobre el tema. Los resultaros mostraron que la mayoria de los valores de los indicadores de eficiencia de estos conjuntos agricolas se encuentran por debajo de las posibilidades tecnicas. Sin embargo, el coeficiente de aprovechamiento del ancho de trabajo (epsilonbeta) para el nivelador del suelo, el coeficiente de aprovechamiento de la velocidad de trabajo (epsilonV) de la grada pesada de 52 discos y el coeficiente de aprovechamiento del tiempo de turno (tau) de los tres agregados se catalogan de aceptables. Se concluye que las magnitudes de productividad real (Wr) obtenidas se comportaron por debajo de las posibilidades reales del conjunto con magnitudes 14,65; 17,71 y 29,1 ha turno.sup.-1 respectivamente. Lo cual se debe a violaciones de los parametros cinematicos durante el trabajo. Palabras clave: ancho de trabajo, velocidad de trabajo, profundidad de trabajo, tiempo de turno y productividad.
