43 research outputs found
A variable stiffness soft gripper using granular jamming and biologically inspired pneumatic muscles
As the domains in which robots operate change the objects a robot may be required to grasp and manipulate are likely to vary significantly and often. Furthermore there is increasing likelihood that in the future robots will work collaboratively alongside people. There has therefore been interest in the development of biologically inspired robot designs which take inspiration from nature. This paper presents the design and testing of a variable stiffness, three fingered soft gripper which uses pneumatic muscles to actuate the fingers and granular jamming to vary their stiffness. This gripper is able to adjust its stiffness depending upon how fragile/deformable the object being grasped is. It is also lightweight and low inertia making it better suited to operation near people. Each finger is formed from a cylindrical rubber bladder filled with a granular material. It is shown how decreasing the pressure inside the finger increases the jamming effect and raises finger stiffness. The paper shows experimentally how the finger stiffness can be increased from 21 to 71 N/m. The paper also describes the kinematics of the fingers and demonstrates how they can be position-controlled at a range of different stiffness values
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Conservation assessments and Red Listing of the endemic Moroccan flora (monocotyledons)
Morocco constitutes an important centre of plant diversity and speciation in the Mediterranean Basin. However, numerous species are threatened by issues ranging from human activities to global climatic change. In this study,
we present the conservation assessments and Red Listing of the endemic Moroccan monocotyledons according to
International Union for Conservation of Nature (IUCN) criteria and categories. For each species, we include basic
taxonomic information, local names and synonyms, uses, a distribution map, extent of occurrence, area of
occupancy, population size and trend, a description of habitats and ecological requirements, and a discussion of the
threats affecting the species and habitats. We assessed the threatened status of the endemic Moroccan monocotyledons
at the species level (59 species) using the IUCN Red List criteria and categories (Version 3.1). This study
shows the high extinction risk to the Moroccan monocotyledon flora, with 95% of threatened species (20% Critically
Endangered, 50% Endangered, 25% Vulnerable) and only 5% not threatened (2% Near Threatened and 3% Least
Concern). The flora is thus of conservation concern, which is poorly recognized, both nationally and internationally.
The study presents the first part and so far the only national IUCN Red Data List for a large group of Moroccan
plants, and thus provides an overview of the threatened Moroccan flora. This IUCN Red List is an important first
step towards the recognition of the danger to Moroccan biodiversity hotspots, conservation of threatened species
and the raising of public awareness at national and international levels
Detektion asymptomatischer SARS-CoV-2 Infektionen in KindertagesstÀtten, Schulen und Unternehmen zur regionalen PandemieeindÀmmung durch ein genossenschaftliches PCR-Testlabor im Zeitraum Juli 2021 bis Juni 2022
As an important element in the regional containment of the COVID-19 pandemic a PCR testing laboratory with a cooperative character was founded in spring 2021 to screen for SARS-CoV-2 in the Nuremberg region, Germany. The aim was to detect asymptomatic infections in day care facilities for children, schools, and companies. The laboratory used an established RT-PCR protocol and analyzed approximately 18,500 pools of up to 25 pooled samples each from gargles or swabs ("lollipops") from up to 135 facilities between July 2021 and June 2022. Usually, the participating facilities were informed about positive pools within a few hours. Retention samples from positive pools were usually analyzed on the same day, and the results were reported to the facilities as well as the German Electronic Reporting and Information System (DEMIS). In the laboratory results, both the local incidences and the transition from the Delta- to the Omicron surge in early 2022 were well reflected. It is plausible that about 4,800 secondary infections could be prevented from the approximately 1,570 positive individual samples detected in conjunction with appropriate isolation measures. Such a PCR laboratory, which is characterized by short response times and high flexibility, can thus provide valuable services for regional surveillance of infection incidence.Als ein wichtiger Baustein zur regionalen EindĂ€mmung der COVID-19 Pandemie wurde im FrĂŒhjahr 2021 ein PCR-Testlabor mit genossenschaftlichem Charakter zum Screening auf SARS-CoV-2 in der Region NĂŒrnberger Land gegrĂŒndet. Ziel war die Detektion asymptomatischer Infektionen in KindertagesstĂ€tten, Schulen und Unternehmen. Das Labor nutzte ein etabliertes RT-PCR Verfahren und analysierte zwischen Juli 2021 und Juni 2022 aus bis zu 135 Einrichtungen rund 18.500 Pools mit je bis zu 25 vereinigten Proben aus Gurgelaten bzw. Abstrichtupfern ("Lollis"). In der Regel wurden die teilnehmenden Einrichtungen innerhalb weniger Stunden ĂŒber positive Pools informiert, RĂŒckstellproben positiver Pools wurden meist noch am selben Tag analysiert und die Ergebnisse an die Einrichtungen sowie das Deutsche Elektronische Melde- und Informationssystem (DEMIS) gemeldet. In den Laborergebnissen bildeten sich ĂŒber den Zeitraum Juli 2021 bis Juni 2022 sowohl die lokalen Inzidenzen als auch der Ăbergang von der Delta- zur Omikron-Welle Anfang 2022 gut ab. Es ist plausibel, dass sich bei den ca. 1.570 detektierten positiven Einzelproben in Verbindung mit geeigneten IsolationsmaĂnahmen etwa 4.800 SekundĂ€rinfektionen verhindern lieĂen. Ein solches PCR-Labor, das sich durch kurze Antwortzeiten und hohe FlexibilitĂ€t auszeichnet, kann somit wertvolle Dienste fĂŒr die regionale Ăberwachung des Infektionsgeschehens leisten