Distributed approach for coverage and patrolling missions with a team of heterogeneous aerial robots under communication constraints

Using aerial robots in area coverage applications is an emerging topic. These applications need a coverage path planning algorithm and a coordinated patrolling plan. This paper proposes a distributed approach to coordinate a team of heterogeneous UAVs cooperating efficiently in patrolling missions around irregular areas, with low communication ranges and memory storage requirements. Hence it can be used with small‐scale UAVs with limited and different capabilities. The presented system uses a modular architecture and solves the problem by dividing the area between all the robots according to their capabilities. Each aerial robot performs a decomposition based algorithm to create covering paths and a ’one‐to‐one’ coordination strategy to decide the path segment to patrol. The system is decentralized and fault‐tolerant. It ensures a finite time to share information between all the robots and guarantees convergence to the desired steady state, based on the maximal minimum frequency criteria. A set of simulations with a team of quad‐rotors is used to validate the approach

An efficient distributed area division method for cooperative monitoring applications with multiple uavs

This article addresses the area division problem in a distributed manner providing a solution for cooperative monitoring missions with multiple UAVs. Starting from a sub-optimal area division, a distributed online algorithm is presented to accelerate the convergence of the system to the optimal solution, following a frequency-based approach. Based on the “coordination variables” concept and on a strict neighborhood relation to share information (left, right, above and below neighbors), this technique defines a distributed division protocol to determine coherently the size and shape of the sub-area assigned to each UAV. Theoretically, the convergence time of the proposed solution depends linearly on the number of UAVs. Validation results, comparing the proposed approach with other distributed techniques, are provided to evaluate and analyze its performance following a convergence time criterion.European Union’s Horizon 2020 AERIAL-CORE Project Grant 871479CDTI (sPAIN) “Red Cervera” Programme iMOV3D Spanish R&D projec

Morphological quality in moringa (Moringa oleifera Lam.) Seedlings produced in substrates composed of soil and animal manure

With the objective of evaluating the morphological quality of moringa seedlings produced in substrates composed of soil with a sandy loam texture and dry and sifted manure of cattle, sheep, pigs, horses, cunicultural, chicken and hen manure, mixed in a 2: 1 ratio (v/v), respectively, and previously characterized physically and chemically, an experiment was conducted in the cultivation house, in the design of randomized blocks with seven treatments, three repetitions, 18 seedlings per experimental unit and four useful seedlings. The speed index (IVE) and total emergency percentage (PE), the evolution of the slenderness index and final slenderness index in the seedlings and other quality indices corresponding to fresh aerial and root biomass at 42 days after sowing were quantified. The quantified variables were processed by Friedman's test and analysis of variance and compared by sum of orthogonal ranges and contrasts at 5% significance. The quantified variables were processed by Friedman's test and analysis of variance and compared by sum of orthogonal ranges and contrasts at 5% significance. For both the IV and the PE, the substrates based on pig, equine and bovine manure had the highest values, while the substrates with chicken and hen manure were not adequate. The evolutionary curves of the slenderness index in the substrates with pig and cunicultural manure maintained a sustained air growth rate. The soil - pig manure substrate was the best option for raising moringa in nursery conditions. The Dickson index, allowed to indicate quality for moringa seedlings in nursery conditions.Con el objetivo de evaluar la calidad morfológica de plántulas de moringa producidas en sustratos compuestos por suelo de textura areno francosa y estiércol seco y tamizado de bovino, ovino, porcino, equino, cunícola, pollinaza y gallinaza, mezclados en proporción 2:1 (v/v), respectivamente, y previamente caracterizados física y químicamente; se condujo un experimento en casa de cultivo, en el diseño de bloques al azar con siete tratamientos, tres repeticiones, 18 plántulas por unidad experimental y cuatro plántulas útiles. Se cuantificó el índice de velocidad y el porcentaje total de emergencia (IVE y PE respectivamente), la evolución del índice de esbeltez e índice de esbeltez final en las plántulas y otros índices de calidad correspondiente a biomasa fresca aérea y radicular a los 42 días después de la siembra. Las variables cuantificadas fueron procesadas por prueba de Friedman y análisis de varianza y comparadas mediante suma de rangos y contrastes ortogonales al 5% de significancia. Tanto para el IVE como para el PE, los sustratos a base de estiércol porcino, equino y bovino presentaron los valores más elevados, mientras los sustratos con pollinaza y gallinaza no resultaron adecuados. Las curvas evolutivas del índice de esbeltez en los sustratos con estiércol porcino y cunícola mantuvieron ritmo de crecimiento aéreo sostenido. El sustrato suelo - estiércol porcino resultó la mejor opción para la crianza de moringa en condiciones de vivero. El índice de Dickson, permitió indicar calidad para las plántulas de moringa en condiciones de vivero

Ten years of cooperation between mobile robots and sensor networks

This paper presents an overview of the work carried out by the Group of Robotics, Vision and Control (GRVC) at the University of Seville on the cooperation between mobile robots and sensor networks. The GRVC, led by Professor Anibal Ollero, has been working over the last ten years on techniques where robots and sensor networks exploit synergies and collaborate tightly, developing numerous research projects on the topic. In this paper, based on our research, we introduce what we consider some relevant challenges when combining sensor networks with mobile robots. Then, we describe our developed techniques and main results for these challenges. In particular, the paper focuses on autonomous self-deployment of sensor networks; cooperative localization and tracking; self-localization and mapping; and large-scale scenarios. Extensive experimental results and lessons learnt are also discussed in the paper

An aerial robot path follower based on the ’Carrot chasing’ algorithm

This paper presents a three-dimensional path follower implementation for an aerial robot based on the carrot-chasing algorithm. The main objective was to improve the performance of the position controller of the PX4 autopilot when following a list of waypoints. This autopilot is widely used in the aerial robotics community, but we needed to improve its performance for navigation in cluttered environments. Different simulations have been carried out under the ROS (Robotic Operating System) environment for the comparison between the position controller of the PX4 and the proposed path follower. In addition, we have implemented different modes to generate the path from the input list of waypoints that are also analyzed in our simulation environment

Aplicación de las nuevas tecnologías de la información y comunicaciones en la educación del S. XXI

This communication summarizes the ambitious project developed by the University of Cantabria in order to make Information and Communications Technologies (ICT) available to the whole academic community in Spain. The development of the European Higher Education Area, and the adaptations that this directive implies, will demand some changes and additional efforts within the usual teaching methods and techniques, where ICT will play a prominent role for users and developers namely students and teachers. Elearning platforms, complemented with distance learning communication devices like videoconferencing systems, and ongoing training of all involved sectors, will be the key for a successful convergence of the European Higher Educational Systems

Las TICs aplicadas a la enseñanza universitaria del EEES

This paper outlines the background of a long term project developed by the University of Cantabria during eight consecutive years, in order to make the Information and Communications Technologies (ICTs) available to Spanish academic community. The development of a European higher education space, and the adaptations that this implies, and demands some changes within the teaching methods and planning, where the ICTs has a prominent role for both students and teachers. E-learning platforms, complemented with nonpresential communication technologies, like videoconferencing and a constant formation of all the involved sectors, will be the key for a successful convergence of the imminent European Higher Education Area (EHEA)

Towards a relevant set of state variables to describe static granular packings

We analyze, experimentally and numerically, the steady states, obtained by tapping, of a two-dimensional granular layer. Contrary to the usual assumption, we show that the reversible (steady state branch) of the density-acceleration curve is nonmonotonous. Accordingly, steady states with the same mean volume can be reached by tapping the system with very different intensities. Simulations of dissipative frictional disks show that equal volume steady states have different values of the force moment tensor. Additionally, we find that steady states of equal stress can be obtained by changing the duration of the taps; however, these states present distinct mean volumes. These results confirm previous speculations that the volume and the force moment tensor are both needed to describe univocally equilibrium states in static granular assemblies

Procedures for the Integration of Drones into the Airspace Based on U-Space Services

A safe integration of drones into the airspace is fundamental to unblock the potential of drone applications. U-space is the drone traffic management solution for Europe, intended to handle a large number of drones in the airspace, especially at very low level (VLL). This paper presents the procedures we have designed and tested in real flights in the SAFEDRONE European project to pave the way for a safe integration of drones into the airspace using U-space services. We include three important aspects: Design of procedures related to no-fly zones, ensure separation with manned aircraft, and autonomous non-cooperative detect-and-avoid (DAA) technologies. A specific U-space architecture has been designed and implemented for flight campaigns with up to eight drones with different configurations and a manned aircraft. From this experience, specific recommendations about procedures to exit and avoiding no-fly zones are presented. Additionally, it has been concluded that the use of surveillance information of manned aircraft will allow a more efficient use of the airspace while maintaining a proper safety level, avoiding the creation of large geofence areas.Programa Horizonte 2020. Unión Europea 78321

Evaluación de la calidad microbiológica y niveles de nitratos y nitritos en las aguas del río Guarapiche, estado Monagas, Venezuela | Evaluation of microbiological quality and levels of nitrates and nitrites in the Guarapiche River, Monagas state, Venezuela

El objetivo fue determinar la calidad microbiológica y los niveles de nitratos y nitritos en las aguas del Río Guarapiche entre Febrero y Julio del 2011. Se analizaron mensualmente a lo largo del río siete estaciones o puntos de muestreos, donde se recolectaron las muestras de aguas. La metodología que se utilizó para la determinación de los microorganismos fue el recuento total de colonias en placas y la técnica del número más probable. Para la determinación de nitrato y nitrito se utilizó un fotómetro multiparamétrico de sobremesa. El río presentó niveles de microorganismos (mesofilos, coliformes totales y fecales), que superan el umbral de la norma vigente del país, en los puntos cercanos a la planta de tratamiento del agua potable del Bajo Guarapiche, producto del crecimiento de los establecimientos poblacionales e incumplimientos de la Ley de Ordenamiento del territorio. Los niveles de nitritos y nitratos en la estación de Merecure estuvieron muy por encima del umbral crítico señalado en el Decreto 883. La mayor problemática ambiental con niveles por encima de los umbrales establecidos para los diferentes parámetros se presenta en la cuenca baja del Río Guarapiche (Maturín y La Pica). Palabras clave: mesófilos, coliformes totales, coliformes fecales, agua de consumo. ABSTRACT The objective was to determine the microbiological quality and levels of nitrates and nitrites in the waters of Guarapiche River between February and July, 2011, water was collected monthly along the river for analysis from seven stations or sampling points. The methodology used for the determination of microorganisms was a combination of total plate counts and the most probable number technique and the determination of nitrate and nitrite was carried out using a multiparameter photometer desktop. The river has levels of microorganisms (mesophiles, total and fecal coliforms) that exceed the current standard of the country, in the sampling points near to the treatment plant of drinking water of Bajo Guarapiche, as a consequence of the growth of local population and breaches of the Land Ordinance Act. The levels of nitrites and nitrates in Merecure station were higher than the critical threshold indicated by the local regulation (Decree 883). The major environmental problem with levels above thresholds for the different parameters was detected in the lower basin of the Guarapiche River (Maturin and La Pica). Key words: mesophiles, total coliforms, fecal coliforms, drinking water