Facultad de Ingeniería Electrónica

El conteo de vehículos es una tarea fundamental en los DIRURV GH WUi¿FR WDQWR SDUD HO GLVHxR GH QXHYDV YtDV FRPR SDUD HO FRQWURO \ OD RSWLPL]DFLyQ GHO WUi¿FR XUEDno. En ciudades como Bogotá, este conteo actualmente se realiza en forma manual, pero puede hacerse automáticamente empleando técnicas de visión por computador. El presente artículo muestra el desarrollo de un algoritmo de detección y seguimiento de vehículos en tiempo real a partir de video, el cual permite el conteo de vehículos en la vía y la estimación del volumen de

Leaf nitrogen (N) directly correlates to chlorophyll production, affecting crop growth and yield. Farmers use soil plant analysis development (SPAD) devices to calculate the amount of chlorophyll present in plants. However, monitoring large-scale crops using SPAD is prohibitively time-consuming and demanding. This paper presents an unmanned aerial vehicle (UAV) solution for estimating leaf N content in rice crops, from multispectral imagery. Our contribution is twofold: (i) a novel trajectory control strategy to reduce the angular wind-induced perturbations that affect image sampling accuracy during UAV flight, and (ii) machine learning models to estimate the canopy N via vegetation indices (VIs) obtained from the aerial imagery. This approach integrates an image processing algorithm using the GrabCut segmentation method with a guided filtering refinement process, to calculate the VIs according to the plots of interest. Three machine learning methods based on multivariable linear re...

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Traditional methods to measure spatio-temporal variations in above-ground biomass dynamics (AGBD) predominantly rely on the extraction of several vegetation-index features highly associated with AGBD variations through the phenological crop cycle. This work presents a comprehensive comparison between two different approaches for feature extraction for non-destructive biomass estimation using aerial multispectral imagery. The first method is called GFKuts, an approach that optimally labels the plot canopy based on a Gaussian mixture model, a Montecarlo-based K-means, and a guided image filtering for the extraction of canopy vegetation indices associated with biomass yield. The second method is based on a Graph-Based Data Fusion (GBF) approach that does not depend on calculating vegetation-index image reflectances. Both methods are experimentally tested and compared through rice growth stages: vegetative, reproductive, and ripening. Biomass estimation correlations are calculated and c...

Non-invasive crop phenotyping is essential for crop modeling, which relies on image processing techniques. This research presents a plant-scale vision system that can acquire multispectral plant data in agricultural fields. This paper proposes a sensory fusion method that uses three cameras, Two multispectral and a RGB depth camera. The sensory fusion method applies pattern recognition and statistical optimization to produce a single multispectral 3D image that combines thermal and near-infrared (NIR) images from crops. A multi-camera sensory fusion method incorporates five multispectral bands: three from the visible range and two from the non-visible range, namely NIR and mid-infrared. The object recognition method examines about 7000 features in each image and runs only once during calibration. The outcome of the sensory fusion process is a homographic transformation model that integrates multispectral and RGB data into a coherent 3D representation. This approach can handle occlusions, allowing an accurate extraction of crop features. The result is a 3D point cloud that contains thermal and NIR multispectral data that were initially obtained separately in 2D.

En el siguiente artículo de investigación se expone de manera académica la conceptualización y diferenciación de términos tales como: cuarta revolución industrial, industria 4.0, industria 5.0 y tecnologías 5G. Los cuales, por el pasar de los años, han sido confundidos y generalizados por su procedencia tecnológica. De esta manera, en primer lugar se desarrolla una contextualización histórica con respecto a las etapas que han acontecido sobre la revolución industrial, seguido de una explicación teórica fundamentada con una revisión de literatura para explicar el significado de cada concepto. Luego se realiza una consideración de cómo estos componentes de orden tecnológico aportan y crean un ambiente más dinámico en aspectos claves como la competitividad, defensa y seguridad en las naciones. Se concluye que la tecnología articulada en la industria y las comunicaciones son un factor importante al equiparar y enfrentar el desarrollo del poder militar como una de las necesidades de prim...

En el siguiente artículo de investigación se expone de manera académica la conceptualización y diferenciación de términos tales como: cuarta revolución industrial, industria 4.0, industria 5.0 y tecnologías 5G. Los cuales, por el pasar de los años, han sido confundidos y generalizados por su procedencia tecnológica. De esta manera, en primer lugar se desarrolla una contextualización histórica con respecto a las etapas que han acontecido sobre la revolución industrial, seguido de una explicación teórica fundamentada con una revisión de literatura para explicar el significado de cada concepto. Luego se realiza una consideración de cómo estos componentes de orden tecnológico aportan y crean un ambiente más dinámico en aspectos claves como la competitividad, defensa y seguridad en las naciones. Se concluye que la tecnología articulada en la industria y las comunicaciones son un factor importante al equiparar y enfrentar el desarrollo del poder militar como una de las necesidades de prim...

En el siguiente artículo de investigación se expone de manera académica la conceptualización y diferenciación de términos tales como: cuarta revolución industrial, industria 4.0, industria 5.0 y tecnologías 5G. Los cuales, por el pasar de los años, han sido confundidos y generalizados por su procedencia tecnológica. De esta manera, en primer lugar se desarrolla una contextualización histórica con respecto a las etapas que han acontecido sobre la revolución industrial, seguido de una explicación teórica fundamentada con una revisión de literatura para explicar el significado de cada concepto. Luego se realiza una consideración de cómo estos componentes de orden tecnológico aportan y crean un ambiente más dinámico en aspectos claves como la competitividad, defensa y seguridad en las naciones. Se concluye que la tecnología articulada en la industria y las comunicaciones son un factor importante al equiparar y enfrentar el desarrollo del poder militar como una de las necesidades de prim...

— This paper describes charging of mobile phones by making use of sound. Basically here the sound energy is converted into electrical energy; the main principle involved in this project is piezoelectric effect which is the conversion of mechanical force or stress into electrical energy. The Zinc Oxide strands are interceded between two electrodes in this system. The sound absorption pad is placed upon the interceded zinc oxide electrodes. When the generated mechanical waves in the form of sound waves strike the sound absorption pad, vibration occurs. This results in the flexing of the zinc oxide wires. The compressions and rare fractions are due to the sensitivity of the Zno. A nano generator is placed between the sandwiched zinc oxide electrodes. The compressions and rare fractions are given to the nano generator. The nanogenerator converts the given mechanical energy into electrical energy. The generated electrical energy is used to charge the battery. Index Terms— sound energy, electrical energy, nanogenrator, zinc oxide nanowires, zinc oxide electrodes, piezoelectric effect.

The recovery of hand motion is one of the most challenging aspects in stroke rehabilitation. This paper presents an initial approach to robot-assisted hand-motion therapies. Our goal was twofold: firstly, we have applied machine learning methods to identify and characterize finger motion patterns from healthy individuals. To this purpose, Electromyographic (EMG) signals have been acquired from flexor and extensor muscles in the forearm using surface electrodes. Time and frequency features were used as inputs to machine learning algorithms for recognition of six hand gestures. In particular, we compared the performance of Artificial Neural Networks (ANN), Support Vector Machines (SVM) and k-Nearest Neighbor (k-NN) algorithms for classification. Secondly, each identified gesture was turned into a joint reference trajectory by applying interpolation methods. This allowed us to reconstruct the hand/finger motion kinematics and to simulate the dynamics of each motion pattern. Experiments were carried out to create an EMG database from 20 control subjects, and a VICON camera tracking system was used to validate the accuracy of the proposed system. The average correlation between the EMG-based generated joint trajectories and the tracked hand-motion was 0.91. Furthermore, statistical analysis applied to 14 different SVM, ANN and k-NN configurations showed that Fine k-NN and Weighted k-NN have a better performance for the classification of gestures (98% of accuracy). In a future, the trajectories controlled by EMG signals could be applied to an exoskeleton or hand-robotic prosthesis for rehabilitation.

This paper presents the design of a bat-like micro aerial vehicle with actuated morphing wings. NiTi shape memory alloys (SMAs) acting as artificial biceps and triceps muscles are used for mimicking the morphing wing mechanism of the bat flight apparatus. Our objective is twofold. Firstly, we have implemented a control architecture that allows an accurate and fast SMA actuation. This control makes use of the electrical resistance measurements of SMAs to adjust morphing wing motions. Secondly, the feasibility of using SMA actuation technology is evaluated for the application at hand. To this purpose, experiments are conducted to analyze the control performance in terms of nominal and overloaded operation modes of the SMAs. This analysis includes: (i) inertial forces regarding the stretchable wing membrane and aerodynamic loads, and (ii) uncertainties due to impact of airflow conditions over the resistance-motion relationship of SMAs. With the proposed control, morphing actuation speed can be increased up to 2.5 Hz, being sufficient to generate lift forces at a cruising speed of 5 m s −1 .

In this paper, we describe our research on bio-inspired locomotion systems using deformable structures and smart materials, concretely shape memory alloys (SMAs). These types of materials allow us to explore the possibility of building motor-less and gear-less robots. A swimming underwater fish-like robot has been developed whose movements are generated using SMAs. These actuators are suitable for bending the continuous backbone of the fish, which in turn causes a change in the curvature of the body. This type of structural arrangement is inspired by fish red muscles, which are mainly recruited during steady swimming for the bending of a flexible but nearly incompressible structure such as the fishbone. This paper reviews the design process of these bio-inspired structures, from the motivations and physiological inspiration to the mechatronics design, control and simulations, leading to actual experimental trials and results. The focus of this work is to present the mechanisms by which standard swimming patterns can be reproduced with the proposed design. Moreover, the performance of the SMA-based actuators' control in terms of actuation speed and position accuracy is also addressed.

In this paper, a system that allows applying precision agriculture techniques is described. The application is based on the deployment of a team of unmanned aerial vehicles that are able to take georeferenced pictures in order to create a full map by applying mosaicking procedures for postprocessing. The main contribution of this work is practical experimentation with an integrated tool. Contributions in different fields are also reported. Among them is a new one-phase automatic task partitioning manager, which is based on negotiation among the aerial vehicles, considering their state and capabilities. Once the individual tasks are assigned, an optimal path planning algorithm is in charge of determining the best path for each vehicle to follow. Also, a robust flight control based on the use of a control law that improves the maneuverability of the quadrotors has been designed. A set of field tests was performed in order to analyze all the capabilities of the system, from task negotiations to final performance. These experiments also allowed testing control robustness under different weather conditions.

Explosive landmines have cost the lives of hundreds in several countries. This paper presents a field report of a low cost unmanned aerial vehicle-ARdrone 2.0-used as a complemented tool for landmine visual detection in rural scenarios. The main contribution of this work is the practical experimentation with an integrated tool. This tool is composed by the ARdrone quadrotor and a base station for monitoring the mission. Based on visual feedback from the onboard camera, algorithms for landmine detection are applied. Experiments have been carried out to quantify the performance of the platform by means of measuring the percentage of the detection at different set of flight speeds and altitudes. The goal is not only to detect fully visible landmines but also those partially buried. It has been observed an effective percentage of the detection over 80% when flying at low altitudes about 1m from the ground at speeds up to 2.2ms −1. The visual methods introduced herein might enable the ARdrone quadrotor to be used as a low-cost autonomous platform for safe area coverage applied to landmine detection in real scenarios.