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Mainly due to the benefits it provides to the distribution systems and also to the environment, the Distributed Photovoltaic Generation (DPVG) is growing in the international energy context. In such promising scenario, is essential to study the positive and negative effects that may be caused by the integration of photovoltaic systems in power distribution grids. This paper aims to propose a generic methodology for analyzing such effects by studying the impacts of the integration of a DPVG into the power distribution grid of one of the campuses of the Federal University of Espirito Santo (Ufes). Parameters such as bus voltage rise or fall, current level, technical losses and power factor changes were verified. An improvement in the voltage profile of the grid and in its operation levels was observed.

The offshore wind power industry is an emerging and exponentially growing sector, which calls to a necessity for a cyclical monitoring and inspection to ensure the safety and efficiency of the wind farm facilities. Thus, the multiple domains of the environment must be reconstructed, namely the emersed (aerial) and immersed (underwater) domains, to depict as much as possible the offshore structures from the wind turbines to the cable arrays. This work proposes the use of an Autonomous Surface Vehicle (ASV) to map both environments simultaneously producing a multi-domain map through the fusion of navigational sensors, GPS and IMU, to localize the vehicle and aid the registration process for the perception sensors, 3D Lidar and Multibeam echosounder sonar.The performed experiments demonstrate the ability of the multi-domain mapping architecture to provide an accurate reconstruction of both scenarios into a single representation using the odometry system as the initial seed to further improve the map with data filtering and registration processes.

The Federal University of Espirito Santo (UFES) has acquired a 5.441 kWp solar photovoltaic distributed generator, which will be installed over the roofs of the buildings of the Goiabeiras Campus in the city of Vitoria, Espirito Santo, Brazil. Knowing that a big amount of active power will be injected in the Goiabeiras Campus’ feeder, while the consumed reactive power will remain the same, the influence of the solar plant over the power factor has been studied. This paper employed data from a meteorological automatic station located in the campus and metering record data to estimate the power factor. Results allow to state that a significant decrease in power factor may be observed in hour intervals with big generation. Nevertheless, results show that possible charges due to extra reactive power are not significant.

This paper presents a new algorithm for a real-time obstacle avoidance for autonomous surface vehicles (ASV) that is capable of undertaking preemptive actions in complex and challenging scenarios. The algorithm is called adaptive velocity obstacle avoidance (AVOA) and takes into consideration the kinematic and dynamic constraints of autonomous vessels along with a protective zone concept to determine the safe crossing distance to obstacles. A configuration space that includes both the position and velocity of static or dynamic elements within the field-of-view of the ASV is supporting a particle swarm optimization procedure that minimizes the risk of harm and the deviation towards a predefined course while generating a navigation path with capabilities to prevent potential collisions.Extensive experiments demonstrate the ability of AVOA to select a velocity estimative for ASVs that originates a smoother, safer and, at least, two times more effective collision-free path when compared to existing techniques.

In this paper, we present an airbag fabrication machine and its process to make airbags which can be utilized for human-machine interaction. The proposed machine uses a CNC-style gantry with XYZ axes to seal layers of thermoplastic sheets in intricate patterns. A custom designed ball transfer is mounted on this machine to control temperature to press, heat, and fuse the thermoplastic sheets. We also implemented a path planning algorithm for heat sealing based on user's drawing. Using the developed machine and process, we demonstrate fabricated airbags can be pressed more than our target pressure and durable to be used in multiple applications over time.

Shipping transportation mode needs to be even more efficient, profitable and secure as more than 80 % of the world's trade is done by sea. Autonomous ships will provide the possibility to eliminate the likelihood of human error, reduce unnecessary crew costs and increase the efficiency of the cargo spaces. Although a significant work is being made, and new algorithms are arising, they are still a mirage and still have some problems regarding safety, autonomy and reliability. This paper proposes an online obstacle avoidance algorithm for Autonomous Surfaces Vehicles (ASVs) introducing the reachability with the protective zone concepts. This method estimates a collision-free velocity based on inner and outer constraints such as, current velocity, direction, maximum speed and turning radius of the vehicle, position and dimensions of the surround obstacles as well as a movement prediction in a close future. A non-restrictive estimative for the speed and direction of the ASV is calculated by mapping a conflict zone, determined by the course of the vehicle and the distance to obstacles that is used to avoid imminent dangerous situations. A set of simulations demonstrates the ability of this method to safely circumvent obstacles in several scenarios with different weather conditions.

The use of telemetry applied to electric power metering systems has made it possible to analyze the phasor behavior of consumers. This analysis not only allows the detection of irregular behavior such as fraud and metering failures, but also helps to identify unexpected effects on the power supply. The register of reverse active power flow in consumers without any installed generating capacity is one such effect. When a facility presents negative active power without having any mini or microgeneration contract drawn up, it is commonly believed that some irregularity is going on. However, after the analysis of some installations with this phasor behavior, it was observed that negative active power can result from authentic passive three-phase loads, causing undue displacements and commitment of resources for the inspection of false positive occurrences of irregularity. This paper demonstrates by means of mathematical modeling of the electric power supply that, under certain circumstances, passive three-phase loads can cause reverse active power flow in one or two of its phases. The circumstances under which such behavior can be observed are described and it is demonstrated that the total active power of a passive facility must always be positive.

Crop monitoring and harvesting by ground robots on mountain vineyards is an intrinsically complex challenge, due to two main reasons: harsh conditions of the terrain and reduced time availability and unstable localization accuracy of the GPS system. In this paper is presented a cost effective robot that can be used on these mountain vineyards for crop monitoring tasks. Also it is explored a natural vineyard feature as the input of a standard 2D simultaneous localization and mapping approach (SLAM) for feature-based map extraction. In order to be possible to evaluate these natural features for mapping and localization purposes, a virtual scenario under ROS/Gazebo has been built and described. A low cost artificial landmark and an hybrid SLAM is proposed to increase the localization accuracy, robustness and redundancy on these mountain vineyards. The obtained results, on the simulation framework, validates the use of a localization system based on natural mountain vineyard features.

This paper describes the development of a prototype of an enclosure for a fuse cutout, for distribution networks of class 15 kV and 36.2 kV. The purpose of the enclosure is to protect the fuse cutout against third party intervention and ensure that only linemen will be able to perform maneuvers and maintenance. Besides protecting the fuse cutout, the enclosure should allow the proper operation of the device while still ensuring signaling the occurrence of events in the distribution network. The enclosure may be used in any fuse cutout, even in operation, with certain nominal characteristics and can still be installed with the line energized.