Today, robotic systems are bridging the gaps between global economy, social needs, and logistics focusing on sustainable development solutions. Everyday new robotic applications can be found in literature and media. Some of them are basically entertainment toys. Nevertheless, the great majority of them is used inside industries, performing several tasks (painting, welding, moving materials, etc.). In a scenario of global economy growth, any sustainable solution that can reduce the product final cost is welcome. This article presents researches on robotic forklifts for intelligent warehouses developed at the Mechatronics Lab at USP-EESC in Brazil. We show three keyroutines that determine the Automated Guided Vehicle (AGV) behavior: the routing algorithm (that computes the overall task execution time and the minimum global path of each AGV using a topological map of the warehouse), the local path planning algorithm (based on A* it searches for the local minimum path between two nodes of the warehouse topological map), and an auto-localization algorithm (that applies an Extended Kalman Filter -EKF -to estimate the AGVs actual positions). In order to validate the algorithms developed, several tests were carried out using the simulation software Player/Stage. The results obtained were encouraging and the router developed was able to solve traffic jams and collisions, before sending the final paths to the robots. In a near future all algorithms will be implemented using mini-robotic forklifts and a scaled environment built in our lab.

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Articles you may be interested inMössbauer study of magnetic structure of cation-deficient iron sulfide Fe 0.92 S

The effect of plasma nitrogenation on the structural and magnetic properties of Pr 2 Fe 17 and Sm 2 Fe 17 compounds was investigated by Mössbauer spectroscopy, thermomagnetic measurements, optical metallography, and electronic microprobe analysis. Samples were prepared starting from Pr 2 Fe 17 and Sm 2 Fe 17 commercial powders with 20 m granulometry, submitted to nitrogenation treatment at 400°C in 10 Torr atmosphere of 80%H 2-20%N 2 during periods up to 8 h. Our results show the formation of R 2 Fe 17 N 3 and metallic Fe and indicate the existence of two other phases. The Mössbauer parameters of the latter are characterized by magnetic hyperfine fields ͑peak values͒ of 21 ͑24͒ and 3 ͑4͒ T and isomer shifts of 0.17 and 0.24 ͑0.24 and 0.29͒ mm/s for Pr ͑Sm͒. Their magnetic-phase transitions were determined to be close to 250 and 90°C. Our results suggest that these 2:17 phases present stoichiometries close to R 2 Fe 17 N 8 and R 2 Fe 17 N 11 , respectively.

A proposta deste trabalho visa promover o desenvolvimento intelectual dos educandos, ao passo que desperte nos mesmos a consciência dos benefícios ambientais e socioeconômicos, provenientes do uso de materiais alternativos e de baixo custo, destacando-se a garrafa pet como principal matéria prima a ser usada na realização e desenvolvimento das atividades propostas aos alunos. Este trabalho baseia-se na Base Orientadora de Ação (BOA III), conforme a Teoria do desenvolvimento das ações mentais de Galperin. Portanto, o educador deve dispor de ações planejadas, objetivas, que possibilitem aos educandos certa organização mental lógica com o intuito de realizar as atividades propostas pelo professor no decorrer do processo de ensino e aprendizagem. Nesse sentido, a escola busca dar uma resposta à comunidade local sugerindo alternativas que venham a colaborar com o desenvolvimento social, econômico e educacional. Logo, a partir do contexto exposto, se faz necessário levar para a sala de aula situações práticas dentro dos conteúdos que venham a somar com o processo de ensino e aprendizagem dos educandos, levando em consideração a realidade da comunidade escolar e suas particularidades.