1,215 research outputs found

    Chapter Hybrid-Powered Autonomous Robots for Reducing Both Fuel Consumption and Pollution in Precision Agriculture Tasks

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    Environmental contamination and the resulting climate change are major concerns worldwide. Agricultural vehicles that use fossil fuels emit significant amounts of atmospheric pollutants. Thus, this study investigates techniques to reduce fuel consumption in robotic vehicles used for agricultural tasks and therefore reduce atmospheric emissions from these automated systems. A hybrid energy system for autonomous robots devoted to weed and pest control in agriculture is modeled and evaluated, and its exhaust emissions are compared with those of an internal combustion engine-powered system. Agricultural implements require power for hydraulic pumps and fans; this energy is conventionally provided by power take-off (PTO) systems, which waste substantial amounts of energy. In this work, we examine a solution by designing and assessing a hybrid energy system that omits the alternators from the original vehicle and modifies the agricultural implements to replace the PTO power with electrical power. The hybrid energy system uses the original combustion engine of the tractor in combination with a new electrical energy system based on a hydrogen fuel cell. We analyze and compare the exhaust gases resulting from the use of (1) an internal combustion engine as the single power source and (2) the hybrid energy system. The results demonstrate that the hybrid energy system reduced emissions by up to approximately 50%

    Hybrid-Powered Autonomous Robots for Reducing Both Fuel Consumption and Pollution in Precision Agriculture Tasks

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    Environmental contamination and the resulting climate change are major concerns worldwide. Agricultural vehicles that use fossil fuels emit significant amounts of atmospheric pollutants. Thus, this study investigates techniques to reduce fuel consumption in robotic vehicles used for agricultural tasks and therefore reduce atmospheric emissions from these automated systems. A hybrid energy system for autonomous robots devoted to weed and pest control in agriculture is modeled and evaluated, and its exhaust emissions are compared with those of an internal combustion engine-powered system. Agricultural implements require power for hydraulic pumps and fans; this energy is conventionally provided by power take-off (PTO) systems, which waste substantial amounts of energy. In this work, we examine a solution by designing and assessing a hybrid energy system that omits the alternators from the original vehicle and modifies the agricultural implements to replace the PTO power with electrical power. The hybrid energy system uses the original combustion engine of the tractor in combination with a new electrical energy system based on a hydrogen fuel cell. We analyze and compare the exhaust gases resulting from the use of (1) an internal combustion engine as the single power source and (2) the hybrid energy system. The results demonstrate that the hybrid energy system reduced emissions by up to approximately 50%

    Detailed Study of Amplitude Nonlinearity in Piezoresistive Force Sensors

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    This article upgrades the RC linear model presented for piezoresistive force sensors. Amplitude nonlinearity is found in sensor conductance, and a characteristic equation is formulated for modeling its response under DC-driving voltages below 1 V. The feasibility of such equation is tested on four FlexiForce model A201-100 piezoresistive sensors by varying the sourcing voltage and the applied forces. Since the characteristic equation proves to be valid, a method is presented for obtaining a specific sensitivity in sensor response by calculating the appropriate sourcing voltage and feedback resistor in the driving circuit; this provides plug-and-play capabilities to the device and reduces the start-up time of new applications where piezoresistive devices are to be used. Finally, a method for bypassing the amplitude nonlinearity is presented with the aim of reading sensor capacitance

    Unmanned Ground Vehicles for Smart Farms

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    Forecasts of world population increases in the coming decades demand new production processes that are more efficient, safer, and less destructive to the environment. Industries are working to fulfill this mission by developing the smart factory concept. The agriculture world should follow industry leadership and develop approaches to implement the smart farm concept. One of the most vital elements that must be configured to meet the requirements of the new smart farms is the unmanned ground vehicles (UGV). Thus, this chapter focuses on the characteristics that the UGVs must have to function efficiently in this type of future farm. Two main approaches are discussed: automating conventional vehicles and developing specifically designed mobile platforms. The latter includes both wheeled and wheel-legged robots and an analysis of their adaptability to terrain and crops

    Cucumber Detection For Precision Agriculture Applications

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    The objective of this research was to explore the feasibility of detecting cucumber fruits in field conditions for autonomous robotic harvesting applications. A high resolution colour camera and a time-of-flight camera are proposed as primary sensors for the design of the sensory system. The preliminary detection algorithm includes a pixel-based classifier that labels areas of interest that belong to cucumber fruits and a registration procedure that combines the results of the aforementioned classifier with the range data provided by the time-of-flight camera. The detection algorithm is extremely simple and efficient, and provides a satisfactory discrimination of the cucumbers fruits with respect to the rest of the elements of the scene. Several experimental tests have been carried out in outdoor conditions in order to evaluate and demonstrate the capabilities of the proposed approach

    On the Biomimetic Design of Agile-Robot Legs

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    The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented

    A gene signature derived from the loss of cdkn1a (P21) is associated with CMS4 colorectal cancer

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    The epithelial–mesenchymal transition (EMT) is associated with tumor aggressiveness and increased invasion, migration, metastasis, angiogenesis, and drug resistance. Although the HCT116 p21-/- cell line is well known for its EMT-associated phenotype, with high Vimentin and low E-cadherin protein levels, the gene signature of this rather intermediate EMT-like cell line has not been determined so far. In this work, we present a robust molecular and bioinformatics analysis, to reveal the associated gene expression profile and its correlation with different types of colorectal cancer tumors. We compared the quantitative signature obtained with the NanoString platform with the expression profiles of colorectal cancer (CRC) Consensus Molecular Subtypes (CMS) as identified, and validated the results in a large independent cohort of human tumor samples. The expression signature derived from the p21-/- cells showed consistent and reliable numbers of upregulated and downregulated genes, as evaluated with two machine learning methods against the four CRC subtypes (i.e., CMS1, 2, 3, and 4). High concordance was found between the upregulated gene signature of HCT116 p21-/- cells and the signature of the CMS4 mesenchymal subtype. At the same time, the upregulated gene signature of the native HCT116 cells was similar to that of CMS1. Using a multivariate Cox regression model to analyze the survival data in the CRC tumor cohort, we selected genes that have a predictive risk power (with a significant gene risk incidence score). A set of genes of the mesenchymal signature was proven to be significantly associated with poor survival, specifically in the CMS4 CRC human cohort. We suggest that the gene signature of HCT116 p21-/- cells could be a suitable metric for mechanistic studies regarding the CMS4 signature and its functional consequences in CRC. Moreover, this model could help to discover the molecular mechanisms of intermediate EMT, which is known to be associated with extraordinarily high stemness and drug resistance.R.S.-S. was supported by the Emerging Fields Initiative ‘Cell Cycle in Disease and Regeneration’ (CYDER) of the Friedrich Alexander University (Erlangen-Nürnberg, Germany). This article is partly based upon work from COST Action CA17118 TRANSCOLONCAN, supported by COST (European Cooperation in Science and Technology, www.cost.eu, last accessed 20 December 2021). The JDLR research group is supported by the Spanish Government, Instituto de Salud Carlos III (ISCiii, AES project PI18/00591) co-funded by FEDER/ERDF (European Regional Development Fund)

    Proyecto de Innovación Docente “MarWatching”

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    Hay a disposición una serie de videos públicos que complementan el tutorial de MyOcean del Capítulo 4 (https://www.youtube.com/playlist?list=PLd7A9IeroEZgAnLudkqbXRAA8bxJrPXJe).El presente documento, financiado por el Programa de Investigación en Docencia Universitaria de la Universidad 2021-22 (Xarxa 5543) tiene el objetivo de facilitar el uso de una serie de herramientas que permitan el estudio y análisis del cambio climático en el ámbito universitario de forma transversal. La base de datos de Copernicus, Programa de Observación de la Tierra de la Unión Europea, en su sección marina (Copernicus Marine Service; https://marine.copernicus.eu/) alberga una infinidad de datos que pueden ser difíciles de manejar por docentes y estudiantes. En concreto, se pretende facilitar el empleo de la herramienta MyOcean de Copernicus (https://marine.copernicus.eu/access-data/ocean-visualisation-tools) a través de este manual y de un curso Moodle y Mooc que estarán disponibles en la web de la UA.REDES DE CALIDAD, INNOVACIÓN E INVESTIGACIÓN EN DOCENCIA UNIVERSITARIA. CONVOCATORIA 2021-22 Vicerrectorat de Transformació Digital. Institut de Ciències de l'Educació

    Fleets of robots for environmentally-safe pest control in agriculture

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    Feeding the growing global population requires an annual increase in food production. This requirement suggests an increase in the use of pesticides, which represents an unsustainable chemical load for the environment. To reduce pesticide input and preserve the environment while maintaining the necessary level of food production, the efficiency of relevant processes must be drastically improved. Within this context, this research strived to design, develop, test and assess a new generation of automatic and robotic systems for effective weed and pest control aimed at diminishing the use of agricultural chemical inputs, increasing crop quality and improving the health and safety of production operators. To achieve this overall objective, a fleet of heterogeneous ground and aerial robots was developed and equipped with innovative sensors, enhanced end-effectors and improved decision control algorithms to cover a large variety of agricultural situations. This article describes the scientific and technical objectives, challenges and outcomes achieved in three common crops

    Systemic Embolism in Amyloid Transthyretin Cardiomyopathy

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    Aims: Although systemic embolism is a potential complication in transthyretin amyloid cardiomyopathy (ATTR-CM), data about its incidence and prevalence are scarce. We studied the incidence, prevalence and factors associated with embolic events in ATTR-CM. Additionally, we evaluated embolic events according to the type of oral anticoagulation (OAC) and the performance of the CHA2DS2-VASc score in this setting. Methods and results: Clinical characteristics, history of atrial fibrillation (AF) and embolic events were retrospectively collected from ATTR-CM patients evaluated at four international amyloid centres. Overall, 1191 ATTR-CM patients (87% men, median age 77.1 years [interquartile range-IQR 71.4–82], 83% ATTRwt) were studied. A total of 162 (13.6%) have had an embolic event before initial evaluation. Over a median follow-up of 19.9 months (IQR 9.9–35.5), 41 additional patients (3.44%) had an embolic event. Incidence rate (per 100 patient-years) was 0 among patients in sinus rhythm with OAC, 1.3 in sinus rhythm without OAC, 1.7 in AF with OAC, and 4.8 in AF without OAC. CHA2DS2-VASc did not predict embolic events in patients in sinus rhythm whereas in patients with AF without OAC, only those with a score ≥4 had embolic events. There was no difference in the incidence rate of embolism between patients with AF treated with vitamin K antagonists (VKAs) (n = 322) and those treated with direct oral anticoagulants (DOACs) (n = 239) (p = 0.66). Conclusions: Embolic events were a frequent complication in ATTR-CM. OAC reduced the risk of systemic embolism. Embolic rates did not differ with VKAs and DOACs. The CHA2DS2-VASc score did not correlate well with clinical outcome in ATTR-CM and should not be used to assess thromboembolic risk in this population
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