134 research outputs found

    Discrimination of social tactile gestures using biomimetic skin

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    The implementation of novel tactile sensors has yielded original mechanisms for human-robot interaction that support the interpretation of complex social scenarios. For instance, the recognition of social tactile gestures is an important requirement in the design of robot companions because it enables the android to engage with human drives. We are interested on implementing such a functionality upon the biomimetic skin of the iCub android

    Soft eSkin:distributed touch sensing with harmonized energy and computing

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    Inspired by biology, significant advances have been made in the field of electronic skin (eSkin) or tactile skin. Many of these advances have come through mimicking the morphology of human skin and by distributing few touch sensors in an area. However, the complexity of human skin goes beyond mimicking few morphological features or using few sensors. For example, embedded computing (e.g. processing of tactile data at the point of contact) is centric to the human skin as some neuroscience studies show. Likewise, distributed cell or molecular energy is a key feature of human skin. The eSkin with such features, along with distributed and embedded sensors/electronics on soft substrates, is an interesting topic to explore. These features also make eSkin significantly different from conventional computing. For example, unlike conventional centralized computing enabled by miniaturized chips, the eSkin could be seen as a flexible and wearable large area computer with distributed sensors and harmonized energy. This paper discusses these advanced features in eSkin, particularly the distributed sensing harmoniously integrated with energy harvesters, storage devices and distributed computing to read and locally process the tactile sensory data. Rapid advances in neuromorphic hardware, flexible energy generation, energy-conscious electronics, flexible and printed electronics are also discussed. This article is part of the theme issue β€˜Harmonizing energy-autonomous computing and intelligence’

    Elastomer-based touch sensor: Visualization of tactile pressure distribution

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    Β© Springer Nature Switzerland AG 2019. This paper presents an elastomer-based tactile sensor that can sense the tactile information in the form of pressure distribution. Our proposed sensor uses a piece of coated elastomer with thin conical pins underneath as the touch medium. The elastomer consists of 91 pins arranged in a honeycomb pattern, each pin can be regarded as a tactile sensing element. They are spaced at 1.5 mm in x and y direction. Each tactile element transfers the applied pressure value into a circular image pattern which can be captured by a camera placed at the end of the sensor structure. The applied pressure over the sensing array can be computed by processing the area of each sensing element. MATLAB is used to process the received images relating the applied pressure to the activated pixels in each circular pattern of the tactile element, and further visualizing the pressure distribution on a reconstructed surface of the sensor. This paper presents the development principle and fabrication process of the proposed sensor. The experimental results have proven the viability of the sensing concept; the prototype sensor can effectively detect single-point touch caused by objects with different dimensions and multi-point touch interactions with a spacing of more than 2.5 mm

    iCLAP: Shape Recognition by Combining Proprioception and Touch Sensing

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    The work presented in this paper was partially supported by the Engineering and Physical Sciences Council (EPSRC) Grant (Ref: EP/N020421/1) and the King’s-China Scholarship Council Ph.D. scholarship

    Rapid Assessment of SARS-CoV-2 Transmission Risk for Fecally Contaminated River Water

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    This is the final version. Available on open access from the American Chemical Society via the DOI in this recordData availability: All software and data used within this study are available free of charge at https://github.com/JamieLab/CoV2-wastewaterFollowing the outbreak of severe acute respiratory syndrome coronavirus (SARS-CoV-2), airborne water droplets have been identified as the main transmission route. Identifying and breaking all viable transmission routes are critical to stop future outbreaks, and the potential of transmission by water has been highlighted. By modifying established approaches, we provide a method for the rapid assessment of the risk of transmission posed by fecally contaminated river water and give example results for 39 countries. The country relative risk of transmission posed by fecally contaminated river water is related to the environment and the populations’ infection rate and water usage. On the basis of in vitro data and using temperature as the primary controller of survival, we then demonstrate how viral loads likely decrease after a spill. These methods using readily available data suggest that sewage spills into rivers within countries with high infection rates could provide infectious doses of >40 copies per 100 mL of water. The approach, implemented in the supplementary spreadsheet, can provide a fast estimate of the upper and lower viral load ranges following a riverine spill. The results enable evidence-based research recommendations for wastewater epidemiology and could be used to evaluate the significance of fecal–oral transmission within freshwater systems.European Union Horizon 2020Engineering and Physical Sciences Research Council (EPSRC

    Haptic Edge Detection Through Shear

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    Most tactile sensors are based on the assumption that touch depends on measuring pressure. However, the pressure distribution at the surface of a tactile sensor cannot be acquired directly and must be inferred from the deformation field induced by the touched object in the sensor medium. Currently, there is no consensus as to which components of strain are most informative for tactile sensing. Here, we propose that shape-related tactile information is more suitably recovered from shear strain than normal strain. Based on a contact mechanics analysis, we demonstrate that the elastic behavior of a haptic probe provides a robust edge detection mechanism when shear strain is sensed. We used a jamming-based robot gripper as a tactile sensor to empirically validate that shear strain processing gives accurate edge information that is invariant to changes in pressure, as predicted by the contact mechanics study. This result has implications for the design of effective tactile sensors as well as for the understanding of the early somatosensory processing in mammals

    The Universal One-Loop Effective Action

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    We present the universal one-loop effective action for all operators of dimension up to six obtained by integrating out massive, non-degenerate multiplets. Our general expression may be applied to loops of heavy fermions or bosons, and has been checked against partial results available in the literature. The broad applicability of this approach simplifies one-loop matching from an ultraviolet model to a lower-energy effective field theory (EFT), a procedure which is now reduced to the evaluation of a combination of matrices in our universal expression, without any loop integrals to evaluate. We illustrate the relationship of our results to the Standard Model (SM) EFT, using as an example the supersymmetric stop and sbottom squark Lagrangian and extracting from our universal expression the Wilson coefficients of dimension-six operators composed of SM fields.Comment: 30 pages, v2 contains additional comments and corrects typos, version accepted for publication in JHE

    A 3β€²-Untranslated Region (3β€²UTR) Induces Organ Adhesion by Regulating miR-199a* Functions

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    Mature microRNAs (miRNAs) are single-stranded RNAs of 18–24 nucleotides that repress post-transcriptional gene expression. However, it is unknown whether the functions of mature miRNAs can be regulated. Here we report that expression of versican 3β€²UTR induces organ adhesion in transgenic mice by modulating miR-199a* activities. The study was initiated by the hypothesis that the non-coding 3β€²UTR plays a role in the regulation of miRNA function. Transgenic mice expressing a construct harboring the 3β€²UTR of versican exhibits the adhesion of organs. Computational analysis indicated that a large number of microRNAs could bind to this fragment potentially including miR-199a*. Expression of versican and fibronectin, two targets of miR-199a*, are up-regulated in transgenic mice, suggesting that the 3β€²UTR binds and modulates miR-199a* activities, freeing mRNAs of versican and fibronectin from being repressed by miR-199a*. Confirmation of the binding was performed by PCR using mature miR-199a* as a primer and the targeting was performed by luciferase assays. Enhanced adhesion by expression of the 3β€²UTR was confirmed by in vitro assays. Our results demonstrated that upon arrival in cytoplasm, miRNA activities can be modulated locally by the 3β€²UTR. Our assay may be developed as sophisticated approaches for studying the mutual regulation of miRNAs and mRNAs in vitro and in vivo. We anticipate that expression of the 3β€²UTR may be an approach in the development of gene therapy

    Evidence for the Complexity of MicroRNA-Mediated Regulation in Ovarian Cancer: A Systems Approach

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    MicroRNAs (miRNAs) are short (∼22 nucleotides) regulatory RNAs that can modulate gene expression and are aberrantly expressed in many diseases including cancer. Previous studies have shown that miRNAs inhibit the translation and facilitate the degradation of their targeted messenger RNAs (mRNAs) making them attractive candidates for use in cancer therapy. However, the potential clinical utility of miRNAs in cancer therapy rests heavily upon our ability to understand and accurately predict the consequences of fluctuations in levels of miRNAs within the context of complex tumor cells. To evaluate the predictive power of current models, levels of miRNAs and their targeted mRNAs were measured in laser captured micro-dissected (LCM) ovarian cancer epithelial cells (CEPI) and compared with levels present in ovarian surface epithelial cells (OSE). We found that the predicted inverse correlation between changes in levels of miRNAs and levels of their mRNA targets held for only ∼11% of predicted target mRNAs. We demonstrate that this low inverse correlation between changes in levels of miRNAs and their target mRNAs in vivo is not merely an artifact of inaccurate miRNA target predictions but the likely consequence of indirect cellular processes that modulate the regulatory effects of miRNAs in vivo. Our findings underscore the complexities of miRNA-mediated regulation in vivo and the necessity of understanding the basis of these complexities in cancer cells before the therapeutic potential of miRNAs can be fully realized
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