Gripper with Average Continuous Reconfigurability for Industrial Robots

Anthropomorphic grippers for robots are used increasingly in robotic applications for handling and assembly. Currently there are several versions of anthropomorphic grippers as projects, prototypes or commercial variants that due to high prices or even for very high ones, are not available for current applications. Among them, high functionality at a relatively low complexity can be noticed in the case of reconfigurable grippers with high reconfigurability, Barrett Hand type. In this context, it is justified finding alternative solutions at lower prices at a lower reconfigurability, with acceptable functionality for current robotic operations. The paper presents an original version of modular anthropomorphic gripper continuous average reconfigurability, with three fingers. There are mentioned, briefly, major structural, kinematic and static issues, a CAD model and CAD simulation for gripping several types of pieces. Furthermore, we intend to achieve a prototype and test it by mounting on an industrial robot.

A 64-year study of a Pied Flycatcher Ficedula hypoleuca population

A nestbox breeding population of Pied Flycatchers Ficedula hypoleuca was monitored during 64 years in a mixed coniferous-deciduous forest area near Örebro, South Central Sweden. The population showed a continuous average decline of c. 0.5 pairs per year, from c. 50% to c. 20% occupancy. There was a strong negative correlation between flycatcher numbers and those of other hole-nesters, but it is doubtful whether any causal relationship existed. Mean laying date was 24 May (17 May—3 June) and showed a negative correlation with mean May temperatures, yet no significant trend over the six decades. Mean laying date did, however, show an increased variation during the last 20 years. Mean clutch size varied between 5.76 and 7.08, with a mean of 6.34. It varied more during the last 30 years but without any significant relationship with mean laying date. A mean of 5.96 young fledged from broods that produced at least one fledgling vs 5.34 for all broods; the lower figure was mainly a consequence of nest predation by Pine Marten Martes martes, particularly after the early 1980s.

EFICIÊNCIA DE DIFERENTES ELEMENTOS FILTRANTES NA PREVENÇÃO DE OBSTRUÇÃO DE GOTEJADORES

EFICIÊNCIA DE DIFERENTES ELEMENTOS FILTRANTES NA PREVENÇÃO DE OBSTRUÇÃO DE GOTEJADORES José Euclides Stipp Paterniani Marcos Eduardo ScatoliniFaculdade de Engenharia Agrícola, Universidade Estadual de Campinas, Campinas, SP. CP 6011, CEP 13083-970, E-mail: [email protected] 1 RESUMO Durante ensaios para verificação de eficiência de retenção de algas em filtros de discos 120 MESH, tela 120 MESH e manta sintética não tecida, foram avaliados o grau de obstrução de gotejadores de labirinto com fluxo turbulento e vazão nominal de 4 L.h-1 e 8 L.h-1. Para determinação da obstrução causada por impurezas não retidas no meio filtrante foram avaliadas a evolução da vazão e da uniformidade estatística dos gotejadores submetidos aos diferentes meios filtrantes durante um período de 22 semanas durante 4 horas diárias e comparadas com uma parcela testemunha sem elemento filtrante. Os resultados mostraram que houve diferença significativa entre o elemento de discos, que apresentou maior uniformidade estatística, os filtros de manta e tela com valores intermediários e a testemunha que apresentou menor uniformidade estatística. No entanto, para caracterizar de maneira definida a diferença no desempenho dos elementos filtrantes, estes valores deveriam vir acompanhados de uma redução contínua na vazão média dos tratamentos, o que foi observado apenas para o elemento de tela com o gotejador de 4 L.h-1. As demais variações da uniformidade estatística foram temporais, provavelmente devido a obstruções temporárias ocasionadas por variações da concentração de sólidos suspensos na água de irrigação. UNITERMOS: Filtragem, Gotejamento, Qualidade da água. PATERNIANI, J.E.S.; SCATOLINI, M.E. EFFICIENCY OF DIFFERENT FILTER ELEMENTS TO PREVENT TRICKLE CLOGGING 2 ABSTRACT This work aimed to verify the efficiency of algae removal in disks 120 mesh, screen 120 mesh, and non woven synthetic fabric filters. It was evaluated the degree of clogging of turbulent flow drippers on 4 L.h-1 and 8 L.h-1 outflow. For blockage determination the outflow evolution and statistics uniformity (Us) of the dripper have been evaluated when submitted to different filter media over 22 weeks, 4 daily hours compared to a control without the filter element. The results indicated significant differences among the elements. The disk element presented greater statistic uniformity. The screen filter and the non woven synthetic fabric element presented intermediate values whereas the parcel with no filter element (control) presented minor statistic uniformity. However, in order to characterize performance differences among them, values should be presented along with a continuous average outflow reduction in all treatments. This pattern was observed only for the screen filter and 4 L.h-1 drippers. The statistics uniformity variation has been probably caused by temporary blockages due to variation in suspended solid concentration in irrigation water. KEYWORDS: filtration, drip irrigation, water quality.