Double-stub loaded microstrip line reader for very high data density microwave encoders

Compact and high-data density microwave encoders useful for motion control and near-field chipless radio frequency identification (chipless-RFID) applications are proposed in this paper. The encoders are chains of metallic strips etched on a dielectric substrate. The reader consists of a microstrip line loaded with a pair of identical open-ended folded stubs located at different positions and oriented face-to-face by their extremes. By displacing the encoder over the extremes of the stubs, interstub coupling arises when a strip is located on top of the stubs, thereby generating two transmission zeros (rather than one) in the frequency response of the line. Thus, the presence of a strip on top of the face-to-face stubs produces a variation in the transmission coefficient of the line, which in turn can be detected by feeding the line with a harmonic signal, conveniently tuned. Encoder motion generates an amplitude modulated (AM) signal at the output port of the line with peaks, or dips, separated by a time distance dictated by the relative velocity between the reader and the encoder. Moreover, by making certain strips of the chain inoperative (e.g., by cutting them), it is possible to encode information that can be read as the absence (logic state "1") or presence (logic state "0") of peaks, or dips, at predefined positions in the output AM signal of the reader line. Since short strips suffice to generate interstub coupling, unprecedented data density per surface (DPS = 26.04 bit/cm 2 ) is obtained, as revealed by the implementation of 6.4 mm × 60 mm 100-bit encoder

3D-printed all-dielectric electromagnetic encoders with synchronous reading for measuring displacements and velocities

Altres ajuts: ICREAIn this paper, 3D-printed electromagnetic (or microwave) encoders with synchronous reading based on permittivity contrast, and devoted to the measurement of displacements and velocities, are reported for the first time. The considered encoders are based on two chains of linearly shaped apertures made on a 3D-printed high-permittivity dielectric material. One such aperture chain contains the identification (ID) code, whereas the other chain provides the clock signal. Synchronous reading is necessary in order to determine the absolute position if the velocity between the encoder and the sensitive part of the reader is not constant. Such absolute position can be determined as long as the whole encoder is encoded with the so-called de Bruijn sequence. For encoder reading, a splitter/combiner structure with each branch loaded with a series gap and a slot resonator (each one tuned to a different frequency) is considered. Such a structure is able to detect the presence of the apertures when the encoder is displaced, at short distance, over the slots. Thus, by injecting two harmonic signals, conveniently tuned, at the input port of the splitter/combiner structure, two amplitude modulated (AM) signals are generated by tag motion at the output port of the sensitive part of the reader. One of the AM envelope functions provides the absolute position, whereas the other one provides the clock signal and the velocity of the encoder. These synchronous 3D-printed all-dielectric encoders based on permittivity contrast are a good alternative to microwave encoders based on metallic inclusions in those applications where low cost as well as major robustness against mechanical wearing and aging effects are the main concerns

Unity GOAP Tool

Unity is the most used real-time 3D (​RT3D​) engine all over the world, with more than 4.5M registered developers. Nowadays Unity engine still don’t have an officially supported tool for the development of artificial intelligence (​AI​) using the goal oriented action planning (​GOAP​) system. In order to solve this lack, some developers have created its own tools to generate GOAP based AI. Some of this tools are initially developed to create videogames or any AI related project and laterpublished on a git platform when the project is released. Some others are directly published on the assets store of unity. What all these mentioned tools have in common is the limited userinterface(​UI​) interactions. In this kind of tools a limitation of UI elements can be an important usability barrier, because uses need UI elements that let them modify and generate all kind of planning data (conditions, action, effects,...) and UI elements that display a clear out put of the resultant behavior. Otherwise,users will no thave enough information about why the AIis not having the desired behavior and will immediately stop using the tool.The objective of this project is to compete with the existing unofficial tools, with a completely new one that let users generate GOAP based AIeasily and fast. This tool will support a worked system of visual editors, with all the necessary UI elements to generate and modify every thing related with the AI planning, and a friendly clean code easy to work with. In order to achieve all the mentioned objectives, we will use an agile methodology that will let us prototype and test all the project functionalities

Strategies to enhance the data density in synchronous electromagnetic encoders

Altres ajuts: ICREA awardIn this paper, we report two different strategies to enhance the data density in electromagnetic encoders with synchronous reading. One approach uses a periodic chain of rectangular metallic patches (clock chain) that determines the encoder velocity, and dictates the instants of time for retrieving the bits of the identification (ID) code. However, contrary to previous electromagnetic encoders, the ID is inferred at both the rising and the falling edges of the clock signal generated by the clock chain. Moreover, the bits of information are not given by the presence or absence of metallic patches at their predefined positions in the so-called ID code chain. With this novel encoding system, a bit state corresponding to a certain instant of time is identical to the previous bit state, unless there is a change in the envelope function of the ID code signal, determined by the additional non-periodic ID code chain. The other encoding strategy utilizes a single chain of C-shaped resonators, and encoding is achieved by considering four different resonator dimensions, corresponding to four states and, hence, to two bits per resonator of the chain. Thus, with these two strategies, the data density is twice the one achievable in previously reported synchronous electromagnetic encoders

Subaqueous barchans and plane beds from deposition of quartz silt

The suspension flow of quartz silt (geometric mean grain size of 4.15 µm), in unfavorable conditions for deposition, is the motivation for the development of different bed morphologies. Particles deposit over a plane nonerodible surface and develop well-defined barchan ripples, barchanoids, and plane beds in flume experiments. Bedload transport of quartz silt by bedform migration is several orders of magnitude smaller than the suspended transport. The final bed morphology is controlled by the suspended sediment concentration and running time of the experiment. The average dimensions of the bedforms after 1-day experiments are 4.93 cm wide, 10.33 cm long, and 0.45 cm high. Cohesive plane beds appear after 2-day and 3-day experiments with very high sediment concentrations (= 22.5 kg=m3). Viscous effects are deemed relevant for the formation of the beds.Peer ReviewedPostprint (author's final draft

Spectral signature barcodes based on S-shaped split ring resonators (S-SRRs)

In this paper, it is shown that S-shaped split ring resonators (S-SRRs) are useful particles for the implementation of spectral signature (i.e., a class of radiofrequency) barcodes based on coplanar waveguide (CPW) transmission lines loaded with such resonant elements. By virtue of its S shape, these resonators are electrically small. Hence S-SRRs are of interest for the miniaturization of the barcodes, since multiple resonators, each tuned at a different frequency, are used for encoding purposes. In particular, a 10-bit barcode occupying 1 GHz spectral bandwidth centered at 2.5 GHz, with dimensions of 9 cm2, is presented in this paper

Angular displacement and velocity sensors based on electric-LC (ELC) loaded microstrip lines

Planar microwave angular displacement and angular velocity sensors implemented in microstrip technology are proposed. The transducer element is a circularly shaped divider/combiner, whereas the sensing element is an electricLC resonator, attached to the rotating object and magnetically coupled to the circular (active) region of the transducer. The angular variables are measured by inspection of the transmission characteristics, which are modulated by the magnetic coupling between the resonator and the divider/combiner. The degree of coupling is hence sensitive to the angular position of the resonator. As compared with coplanar waveguide angular displacement and velocity sensors, the proposed microstrip sensors do not require air bridges, and the ground plane provides backside isolation

Mechanically reconfigurable microstrip lines loaded with stepped impedance resonators and potential applications

This paper is focused on exploring the possibilities and potential applications of microstrip transmission lines loaded with stepped impedance resonators (SIRs) etched on top of the signal strip, in a separated substrate. It is shown that if the symmetry plane of the line (a magnetic wall) is perfectly aligned with the electric wall of the SIR at the fundamental resonance, the line is transparent. However, if symmetry is somehow ruptured, a notch in the transmission coefficient appears. The notch frequency and depth can thus be mechanically controlled, and this property can be of interest for the implementation of sensors and barcodes, as it is discussed

Application of RF-MEMS-Based Split Ring Resonators (SRRs) to the Implementation of Reconfigurable Stopband Filters : a Review

In this review paper, several strategies for the implementation of reconfigurable split ring resonators (SRRs) based on RF-MEMS switches are presented. Essentially three types of RF-MEMS combined with split rings are considered: (i) bridge-type RF-MEMS on top of complementary split ring resonators CSRRs; (ii) cantilever-type RF-MEMS on top of SRRs; and (iii) cantilever-type RF-MEMS integrated with SRRs (or RF-MEMS SRRs). Advantages and limitations of these different configurations from the point of view of their potential applications for reconfigurable stopband filter design are discussed, and several prototype devices are presented

Microwave sensors based on symmetry properties of resonator-loaded transmission lines

This review paper is focused on the design of microwave sensors using symmetry properties of transmission lines loaded with symmetric resonators. The operating principle of these sensors is presented and then several prototype devices are reported, including linear and angular displacement sensors and rotation speed sensors. The main advantage of the proposed sensors is the robustness against changing environmental conditions