Sunday, December 10, 2017
welcome ! I need this upfront any operation, boolean tribe: Human climbing with efficiently scaled gecko-inspired dry adhesives Since the discovery of the mechanism of adhesion in geckos, many synthetic dry adhesives have been developed with desirable gecko-like properties such as reusability, directionality, self-cleaning ability, rough surface adhesion and high adhesive stress. However, fully exploiting these adhesives in practical applications at different length scales requires efficient scaling (i.e. with little loss in adhesion as area grows). Just as natural gecko adhesives have been used as a benchmark for synthetic materials, so can gecko adhesion systems provide a baseline for scaling efficiency. In the tokay gecko (Gekko gecko), a scaling power law has been reported relating the maximum shear stress σmax to the area A: σmax ∝ A−1/4. We present a mechanical concept which improves upon the gecko's non-uniform load-sharing and results in a nearly even load distribution over multiple patches of gecko-inspired adhesive. We created a synthetic adhesion system incorporating this concept which shows efficient scaling across four orders of magnitude of area, yielding an improved scaling power law: σmax ∝ A−1/50. Furthermore, we found that the synthetic adhesion system does not fail catastrophically when a simulated failure is induced on a portion of the adhesive. In a practical demonstration, the synthetic adhesion system enabled a 70 kg human to climb vertical glass with 140 cm2 of adhesive per hand.
The length scale on which we focus in this work is the human scale, motivated by the challenge of human climbing with a gecko-inspired dry adhesive. The adhesive chosen for this task consists of polydimethylsiloxane (PDMS) slanted microwedges (roughly 100 μm tall), which adhere well to glass and can be repositioned many times without degradation [4,5] (figure 1, inset). While other dry adhesive materials produce larger adhesive stresses, PDMS microwedges are especially suitable for climbing because they exhibit controllable adhesion that can be effectively switched on or off in a fraction of a second by applying a shear stress. Therefore, a climber can attach PDMS microwedges simply by transferring weight to the adhesive, and can detach by removing the weight, requiring nearly-zero added effort. However, this work, on efficient scaling, is not specific to PDMS microwedges and may be applicable to a wide range of other adhesive materials.
Figure 1.
The red squares (n = 5) indicate the maximum adhesive shear stress σmax that can be achieved on a flat, smooth surface by tokay gecko adhesion systems as the adhesive area A increases [6]. From left, these data correspond to a single seta, a setal array, a toe and two feet. The red line shows the least-squares power law fit to the data (log σmax = –0.24 log A + 1.1). Similarly, for the PDMS microwedge synthetic adhesion system, the blue diamonds (n = 6) represent the maximum adhesive stress produced by a 1.5 mm2 patch, a 12 mm2 patch, a 6.5 cm2 tile and a 24-tile system. The least-squares power law is plotted as a blue dashed line (log σmax = –0.02 log A + 1.8).
There have been notable efforts to scale adhesives beyond small laboratory tests, but there has been little work dealing specifically with scaling efficiency. Researchers have created small robots that climb well with dry adhesives [7–11], yet these systems cannot support as large a load as predicted by their total area of adhesive. For instance, Stickybot had an area of adhesive that should have supported 5 kg based on small-scale tests, but could only support 500 g owing to inefficient scaling [11]. In other work, adhesive anchors capable of holding impressive loads have been created [12,13], but the scaling efficiency of these adhesion systems has not been reported. Additionally, a demonstration of human climbing with gecko-inspired adhesives has been recently revealed by the Defense Advanced Research Projects Agency (DARPA) Z-Man programme [14], but details of the adhesive material, climbing device and total area of adhesive remain undisclosed.
Without scaling efficiency numbers in the literature, it is useful to set a scaling efficiency benchmark by turning towards the adhesion systems of geckos, as designers of dry adhesives have done previously to judge the relative merits of their synthetic materials. In the tokay gecko (Gekko gecko), the adhesion decreases as the length scale increases from the seta-scale to the toe- and foot-scale [6]. This adhesion system has been found to approximately follow a scaling power law, σmax ∝ A−1/4, where σmax is the maximum shear stress supported by the adhesive and A is the adhesive area (figure 1, red squares).
If the benchmark power law of the tokay gecko were applied to the PDMS microwedge adhesive, an impractically large area of more than 1200 cm2 of adhesive per hand would be required to support a 70 kg human climber with no safety factor (a modern tennis racket is approx. 675 cm2). This is partly because the area of adhesive required for climbing increases disproportionately as the scale increases (even with perfectly efficient scaling) owing to the climber's surface area and mass following a square-cube law.
Therefore, to allow a human to climb with a practical area of controllable dry adhesive, it is necessary to attain significantly more efficient scaling than that of the gecko's adhesion system. To achieve this goal, we developed a synthetic adhesion system which ensures that the load distribution across a large adhesive area is nearly uniform, using a concept referred to as degressive load-sharing. In degressive load-sharing, elastic elements which have decreasing stiffness with increasing displacement support independent patches of adhesive and help equalize the load on all patches. The synthetic adhesion system was found to sustain adhesive stress with little decrease across four orders of magnitude of area, approximately following the power law σmax ∝ A−1/50 (figure 1, blue diamonds). Furthermore, the system was found to resist catastrophic failure by preventing stress concentrations when a simulated failure was induced on a portion of the adhesive (see §2.3), and the system also requires little effort to attach or detach (see §2.5). Thus, with efficient scaling, robustness to failure and controllable adhesion, the synthetic adhesion system enables a human to ascend a vertical glass surface with a hand-sized1 area of adhesive (figure 2).
Figure 2.
Three frames from a video (electronic supplementary material, movie S1) showing a 70 kg climber ascending a 3.7 m vertical glass surface using a synthetic adhesion system with degressive load-sharing and gecko-inspired adhesives. The time between (a) and (c) is about 90 s and includes six steps.
Saturday, December 9, 2017
Diffraction Grating, Transmission Hologram MI6 glasses ----- difrattion grating and how transmission of holograms...their glasses just shine a laser on "any "lens" material, and the hologram is transmitted...next part, the laser is up on your right side up, on the lens , it has a coupler nano transmitter with wifi and microphone
so, actually the lens from the MI6 movies are these product
Hamamatsu LCOS Spatial Light Modulator
The LCOS-SLM is a reflective type of pure phase Spatial Light Modulators (SLMs), based on Liquid Crystal on Silicon (LCOS) technology in which liquid crystal (LC) is controlled by a direct and accurate voltage, and can modulate a wavefront of light beam. The LCOS-SLMs are carefully designed to achieve high light utilization efficiency from various points of view, such as reflectivity, aperture ratio and diffraction noise due to the pixel structure.
http://eqdb.nrf.ac.za/equipment/other/hamamatsu-lcos-spatial-light-modulator
welcome! The Revolution means you destroy every mean of their warfare apparatus. This "polymer support layer with acoustic impedance" and "piezoelectric film" when strategic implanted on the surface, will active deny F-35's electronics systems. And ...bye bye 120 million dollars, if its only one making recognition.
Friday, December 8, 2017
let's move to the plan. fingerprints ...20.º degrees, iris recognition
Light Shaping Diffusers (LSDs)
1. What Is a Light Shaping Diffuser?
Light Shaping Diffusers are micro-structures pseudo randomly embedded on a substrate (such as film). When applied to a lighting structure, the LSD can manipulate light by changing the direction of its energy. This allows our Light Shaping Diffusers to clean up and shape a light beam to suit a particular purpose.
2. Where are LSDs used?
LSD are often applied in architectural lighting, can lights, decorative lighting, pool lighting, set/event lighting and wall wash lighting where the effects of LSD can be quite dramatic. LSDs are also used in illumination systems such as aircraft inspection lights; backlit systems such as cellphone and PDA displays; LCD screens and more.
3. What sizes of LED light diffusers are available?
Thin film LSDs are available in rolls, sheets or parts cut to your specifications. Standard rolls are 20” wide and 500’ long. Strip rolls are also available in your specified width.
4. Are the diffusers available for smaller applications?
Yes, Luminit Light Shaping Diffusers are available in various circular and elliptical angles in pre-cut sheet format for lower volume applications.
5. What angles are available ?
Luminit light diffusers are available in a variety of circular and elliptical angles from 1° to 100° on thin film or rigid substrates.
6. What is the transmission efficiency of Luminit diffusers?
The transmission efficiencies of Luminit LSDs are rated between 85-92% (depending on the angle). This very high-efficiency rating is due to the fact that our technology is based on diffractive microstructures. Smaller angle diffusers have the highest transmission.
7. Is the angle of diffusion and transmission wavelength dependent?
Since our microstructures are random and non-periodic, the LSD is not wavelength dependent, so it works well from 400nm to 1500nm.
8. Can Luminit LED lighting diffusers reduce hotspots with LED lights?
Yes, Luminit Light Shaping Diffusers eliminate the hotspots without a significant reduction in the amount of the light, provided that the diffuser is placed a sufficient distance from the LEDs. A rule of thumb is that the diffuser must be at least as far away from the LEDs as the LEDs are spaced apart.
9. Can Light Shaping Diffusers shape light beams?
Yes, Luminit LSD are so precise that beam shaping is possible. Our patented holographic master recording process allows a variety of circular and elliptical light patterns. Standard circular angles range from 0.5˚ to 100˚ FWHM. A wide variety of standard elliptical angles, ranging from 10˚x0.2˚ to 95˚x35˚, are available.
10. What does FWHM mean?
FWHM is an abbreviation for Full-Width Half-Maximum which is the angle of diffusion that would be seen after a collimated laser passes through the diffuser.
Actually most handy James Bond's tool...for electronic lockpicking
The Rotary Encoder LED Ring is a position indicator for rotary encoders. Traditional knobs with indicator lines do not give accurate representation of an encoder’s value since rotary encoders have no start or end point. The Rotary Encoder LED Ring has thru-hole or shaft mounting for most standard encoders and uses a Texas Instruments TLC5925 shift register to interface 16 blue LEDs to any microcontroller through SPI. A microcontroller can be programmed to output any desired sequence on the LEDs.
https://www.riecktron.co.za/en/product/1359
welcome.... energy blackouts! This is a device, that works on thermal emissions and radio waves. Its a russian manafucter, and no one else has this product. this will work on the electricity grid has a emission of "impurities" to the cable lines. Something I learned form Physics class, electricity does not go along with "impurities"
Thursday, December 7, 2017
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