Nanowerk April 10, 2024 Existing tactile sensing gloves fall short in terms of user comfort and are ill-suited for underwater applications. Researchers in China proposed and constructed a flexible hand gesture recognition glove (GRG) that contained high-performance micropillar tactile sensors (MPTSs) inspired by the flexible tube foot of a starfish. The sensor has a wide working range, superfast response time, reliable repeatability, and a low limit of detection and they were waterproof. When integrated with machine learning algorithm, the GRG system achieved intelligent recognition of 16 hand gestures under water, extending real-time and effective communication capabilities for divers. According to […]
Tag Archives: Biomimetics
Backyard insect inspires invisibility devices, next gen tech
Phys.org March 18, 2024 The leafhoppers cover their body surfaces with brochosomes, buckyball-shaped, nanoscopic spheroids with through-holes distributed across their surfaces, representing a class of deployable optical materials that are rare in nature. A team of researchers in the US (University of Pennsylvania, Carnegie Mellon University) investigated the optical form-to-function relationship of brochosomes and demonstrated that the hierarchical geometries of brochosomes are engineered within a narrow size range with through-hole architecture to significantly reduce light reflection. They showed that the diameters of brochosomes are engineered to maximize broadband light scattering, while the secondary through-holes are designed to function as short-wavelength, […]
Unveiling the invisible: A bioinspired CMOS-integrated polarization imaging sensor
Phys.org September 18, 2023 Chip-integrated, fast, cost-effective, and accurate full-Stokes polarimetric imaging sensors are highly desirable in many applications, but they remain elusive due to fundamental material limitations. Researchers at the State University of Arizona have developed a chip-integrated Metasurface-based Full-Stokes Polarimetric Imaging sensor (MetaPolarIm) by integrating an ultrathin (~600 nm) metasurface polarization filter array (MPFA) onto a visible imaging sensor with CMOS compatible fabrication processes. The MPFA has broadband dielectric-metal hybrid chiral metasurfaces and double-layer nanograting polarizers. This chip-integrated polarimetric imaging sensor enabled single-shot full-Stokes imaging (speed limited by the CMOS imager) with the most compact form factor, recorded high […]
New textile unravels warmth-trapping secrets of polar bear fur
Science Daily April 10, 2023 There are evidence that polar-dwelling animals have evolved a different mechanism of thermoregulation by using optical polymer materials to achieve an on-body “greenhouse” effect. Researchers at UMass Amherst designed a bilayer textile to mimic these adaptations. They showed that two ultralightweight fabrics with complementary optical functions, a polypropylene visible-transparent insulator and a nylon visible-absorber–infrared-reflector coated with a conjugated polymer, performed the same putative function as polar bear hair and skin, respectively. While retaining familiar textile qualities, these layers suppressed dissipation of body heat and maximized radiative absorption of visible light. Under moderate illumination of 130 […]
Tiny biobattery with potential 100-year shelf life runs on bacteria
Phys.org April 12, 2023 Controllable microbial electrocatalytic activity in a miniaturized microbial fuel cells (MFCs) with unlimited biodegradable energy resources would enable simple power generation in various environmental settings. However, the short shelf-life of living biocatalysts, few ways to activate the stored biocatalysts, and extremely low electrocatalytic capabilities render the miniature MFCs unsuitable for practical use. Researchers at State University of New York at Binghamton used heat-activated Bacillus subtilis spores as a dormant biocatalyst that could survive storage and rapidly germinate when exposed to special nutrients that are preloaded in the device. A microporous, graphene hydrogel allowed the adsorption of […]
Resilient bug-sized robots keep flying even after wing damage
Science Daily March 15, 2023 Although robots driven by rigid actuators have demonstrated agile locomotion and manipulation, most of them lack animal-like robustness against unexpected damage. Dielectric elastomer actuators (DEAs), a class of muscle-like soft transducers, have enabled nimble aerial, terrestrial, and aquatic robotic locomotion. However, unlike muscles, DEAs suffer local dielectric breakdowns that often cause global device failure. Researchers at MIT developed DEAs that can endure more than 100 punctures while maintaining high bandwidth and power density sufficient for supporting energetically expensive locomotion such as flight. They fabricated electroluminescent DEAs for visualizing electrode connectivity under actuator damage. When the […]
Designing advanced ‘BTS’ materials for temperature and long-wave infrared sensing
Phys.org February 20, 2023 Replicating the molecular structure and functional motifs of biological compounds often provide clues to advance material designs and offers a blueprint for unprecedented functionalities. An international team of researchers (USA – Caltech, South Korea) has developed a flexible biomimetic thermal sensing (BTS) polymer that was designed to emulate the ion transport dynamics of a plant cell wall component, pectin. Using a simple yet versatile synthetic procedure, they engineered the physicochemical properties of the polymer by inserting elastic fragments in a block copolymer architecture, making it flexible and stretchable. The thermal response of the flexible polymer outperformed […]
A liquid laser that is robust in air and tunable by wind
Phys.org February 10, 2023 Lasers made solely from liquids are promising toward flexible lasers, but they are intrinsically unstable and have been inapplicable to steady operation under ambient conditions unless they are enclosed in a tailored container or a matrix to prevent the evaporation of the liquid. To simulate the near-perfect water droplets that form on the lotus leaves and roll off, an international team of researchers (Japan, Germany) mixed 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4) with a dye that allowed it to become a laser. The droplets were highly robust and worked as efficient long-lasting laser oscillators. The lasing wavelength was sensitively […]
Recreating the natural light-harvesting nanorings in photosynthetic bacteria
Science Daily January 31, 2023 Photosynthesis in plants and some bacteria relies on light-harvesting (LH) supramolecules which come in different structures. So far, these LH molecules have not been artificially prepared. Researchers in Japan demonstrated that mixing a chlorophyll derivative with naphthalenediamide in an organic solvent leads to the formation of dimers that spontaneously self-assembled into ring-shaped structures, each several hundred nanometers in diameter. They observed that chlorophyll dimers, molecules composed of two chlorophyll units linked by naphthalene, initially self-assembled into stable wavy nanofibers. Upon heating these nanofibers at 50°C, they disassembled into smaller nanoring precursors whose ends eventually joined […]
Breathing supercapacitor
Nanowerk January 13, 2023 Currently commercialized supercapacitors still suffer from limited energy densities. Taking inspiration from anolis lizard, an international team of researchers (UK, China) has developed a supercapacitor with a “breathing” electrode. To breathe underwater the lizard brings along an air bubble that is attached to a layer of scales on their head. Under water, it repeatedly breathes this bubble in and out. The researchers used chlorine gas which iteratively reinspires in porous carbon materials, that improves the energy density by orders of magnitude. They showed that porous carbon with pore size around 3 nm delivers the best chlorine […]