Quantifying Robotic Swarm Coverage

In the field of swarm robotics, the design and implementation of spatial density control laws has received much attention, with less emphasis being placed on performance evaluation. This work fills that gap by introducing an error metric that provides a quantitative measure of coverage for use with any control scheme. The proposed error metric is continuously sensitive to changes in the swarm distribution, unlike commonly used discretization methods. We analyze the theoretical and computational properties of the error metric and propose two benchmarks to which error metric values can be compared. The first uses the realizable extrema of the error metric to compute the relative error of an observed swarm distribution. We also show that the error metric extrema can be used to help choose the swarm size and effective radius of each robot required to achieve a desired level of coverage. The second benchmark compares the observed distribution of error metric values to the probability density function of the error metric when robot positions are randomly sampled from the target distribution. We demonstrate the utility of this benchmark in assessing the performance of stochastic control algorithms. We prove that the error metric obeys a central limit theorem, develop a streamlined method for performing computations, and place the standard statistical tests used here on a firm theoretical footing. We provide rigorous theoretical development, computational methodologies, numerical examples, and MATLAB code for both benchmarks.Comment: To appear in Springer series Lecture Notes in Electrical Engineering (LNEE). This book contribution is an extension of our ICINCO 2018 conference paper arXiv:1806.02488. 27 pages, 8 figures, 2 table

Electro-Deposition of Carbon Structures at Mid Voltage and Room Temperature Using Ethanol/Aqueous Solutions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Direct syntheses of carbon structures including nanodiamond, microdiamond and diamond-like carbon (DLC) on silicon wafers by liquid phase electro-deposition are presented. The solution (ethanol/water) was employed as electrolyte at different concentration levels. Assays were carried out maintaining constant the electric potential between the silicon electrodes in the range of (80-300 V) at current density of approximately 2.0 mA/cm(2). Scanning electron microscopy showed that non-uniform, smooth and heterogeneous structures were produced. The structural composition was evaluated by micro-Raman spectroscopy. A mechanism for the formation of sp(3) and sp(2) hybridizations is proposed. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.066203jes] All rights reserved.1593D159D161Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Interbasin Water Transfers: The Brazilian Experience and International Case Comparisons

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)This paper critically examines Brazil's transbasin diversion experiences and two select, large-scale transbasin projects outside of Brazil. Rather than simply compare Brazil's experiences with international cases, the authors explore the historical context of the projects, focusing on the water resources and environmental regulatory and institutional frameworks in place during the initial proposals and how they influenced the projects' development and completion rates. Huge investments, the lengthy time span between the date of the initial project proposals and the start of construction, the need to garner public and political support, and more recently, the need to fulfill national and regional environmental laws are major factors underlying heated public debates about the proposed projects. After a broad discussion about the subject, the authors examine a recently approved large-scale Brazilian project, the Sao Francisco river transbasin diversion. This river diversion project is considered crucial to the economic development of Brazil's semi-arid northeastern region. Despite the fact that this government-funded project was debated for several decades among the various stakeholders, it was approved under Brazil's newly formed water resources regulatory and environmental framework, which enabled improvements in various key technical aspects of the project, and greater involvement of various key social players.25819151934Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2008/58508-1