42 research outputs found
Comparison between new families of Double-Layer Tensegrity Grids
Rot-Umbela manipulations permit conventional double-layer grids (DLG) to be transformed into tensegrity grids. By means of this method, two new tensegrity modules (Quastrut and Sixstrut) were already discovered. The aim of this work is to compare the behavior of the new family of Double-Layer Tensegrity Grids (DLTG) obtained by the juxtaposition of the Quastrut in some of its variations depending on enantiomorphic variants (e.g. monogyre Vs. racemic), orientations (e.g. 0º Vs. 90º) and configurations (e.g. open Vs. closed). It will be possible to determine which DLTG performs better taking into account their resistance, structural efficiency, deflection, etc. Furthermore, analysis of their mechanisms and states of self-stress could help to understand their structural characteristics better. Deployability will be revealed as one of the most challenging and interesting potentials of these DLTGs
Double-layer tensegrity grids and Rot-Umbela manipulations
RESUMEN.
Las mallas tensegríticas de doble capa
(MTDC) son estructuras de Tensegridad
que contiene dos mallas traccionadas
paralelas, unidas por otra capa intermedia
compuesta por elementos comprimidos y
traccionados verticales y/o diagonales.
Este trabajo presenta inicialmente un
breve repaso sobre las propuestas de
MTDC que se han realizado hasta el
momento, exponiendo luego una nueva
metodología, eminentemente geométrica,
para la generación de este tipo de
estructuras tensegríticas.
Tras aplicar la propuesta de Otero para
generar mallas de doble capa (MDC)
convencionales, se procede a realizar
Manipulaciones de Rot-Umbela en las
capas inferior y/o superior para convertir
dicha estructura en una MTDC. Las
Manipulaciones de Rot-Umbela consisten
en la apertura de cada vértice en un
cierto polígono, al cual se le aplica una
rotación o giro particular. Se consigue así
un potente sistema para “tensegritizar”
MDC convencionales y abrir una línea
de investigación muy interesante en el
campo de la Tensegridad.ABSTRACT. Double-layer tensegrity grids (DLTGs)
are tensegrity spatial systems containing
two parallel networks of members
in tension forming the top and bottom
chords, whose nodes are linked by vertical
and/or inclined web members under
compression and tension.
This paper presents, as an introduction,
a brief perspective of the historical
proposals for DLTGs over the last years,
describing later a new approach for generating
these kinds of structures, mainly
in geometrical terms.
After applying Otero’s proposal for
designing conventional double-layer
grids (DLGs), a new technique, known
as Rot-Umbela Manipulation, is applied
to their upper and/or lower layers for
generating DLTGs. Rot-Umbela Manipulation
consists of opening a vertex in the
plane for obtaining a certain polygon,
which is then rotated by a determined
angle. This powerful operation opens an
endless catalogue of DLTGs and a very
interesting line of research in the field of
Tensegrity
Habidite: viviendas modulares industrializadas
RESUMEN. En este artículo se realiza una breve introducción
a uno de los sistemas constructivos que
más auge está teniendo en los últimos años: la
edificación industrializada integral. Realizado
a base de módulos tridimensionales, es éste un
método de construcción en el cual los edificios
se conforman básicamente por medio de células
espaciales de grandes dimensiones; estos módulos
tridimensionales se elaboran íntegramente en
fábrica y, una vez están totalmente terminados,
se transportan a obra, donde son montados de
forma sencilla y rápida. Aunque no es un sistema
totalmente novedoso (de hecho sus antecedentes
también serán tratados brevemente en este
texto), Habidite apuesta fuertemente por esta
tendencia y aporta su grano de arena para conseguir
edificios modulares de hormigón armado
de extraordinaria calidad, con implementos domóticos
totalmente integrados en la vivienda y
un alto grado de sostenibilidad, eco-tecnología
y eficiencia energética. Se abordan, a lo largo
de la exposición, las ventajas que aporta este
sistema, con la optimización de los procesos
productivos en el sector de la construcción por
medio de la implementación de las más avanzadas
tecnologías.ABSTRACT. This paper is an introduction to one of the most
relevant constructive systems of the last years:
The integral industrialized construction. This method,
based on three-dimensional modules, produces
buildings made mainly from spatial cells of
big dimensions; these three-dimensional modules
are fabricated entirely in factory and, once they
are finished, they are carried out to the site, where
they are assembled in an easy manner. Even
though it’s not a totally new system (in fact, the
precedents will also be mentioned in this essay),
Habidite is very confident in backing this tendency
and doing its part in order to obtain modular
reinforced concrete buildings of extraordinary
quality, with domotic implements totally integrated
in the dwellings and a high degree of sustainability,
eco-technology and energetic efficiency.
Many advantages are exposed and explained,
dealing with the optimization of the productive
processes in construction by means of the most
advanced technologies
Information Management and Improvement of Citation Indices
Bibliometrics and citation analysis have become an important set of methods for library and information science, as well as an exceptional source of information and knowledge for many other areas. Their main sources are citation indices, which are bibliographic databases like Web of Science, Scopus, Google Scholar, etc. However, bibliographical databases lack perfection and standardization. There are several software tools that perform useful information management and bibliometric analysis importing data from them. A comparison has been carried out to identify which of them perform certain pre-processing tasks. Usually, they are not strong enough to detect all the duplications, mistakes, misspellings and variant names, leaving to the user the tedious and time-consuming task of correcting the data. Furthermore, some of them do not import datasets from different citation indices, but mainly from Web of Science (WoS).
A new software tool, called STICCI.eu (Software Tool for Improving and Converting Citation Indices - enhancing uniformity), which is freely available online, has been created to solve these problems. STICCI.eu is able to do conversions between bibliographical citation formats (WoS, Scopus, CSV, BibTex, RIS), correct the usual mistakes appearing in those databases, detect duplications, misspellings, etc., identify and transform the full or abbreviated titles of the journals, homogenize toponymical names of countries and relevant cities or regions and list the processed data in terms of the most cited authors, journals, references, etc
GomJau-Hogg´s Notation for Automatic Generation of k-Uniform Tessellations with ANTWERP v3.0
ABSTRACT: Euclidean tilings are constantly applied to many fields of engineering (mechanical, civil, chemical, etc.). These tessellations are usually named after Cundy & Rollett’s notation. However, this notation has two main problems related to ambiguous conformation and uniqueness. This communication explains the GomJau-Hogg’s notation for generating all the regular, semi-regular (uniform) and demi-regular (k-uniform, up to at least k = 3) in a consistent, unique and unequivocal manner. Moreover, it presents Antwerp v3.0, a free online application, which is publicly shared to prove that all the basic tilings can be obtained directly from the GomJau-Hogg’s notation
Structural analysis of a deployable double-layer tensegrity grid
Congreso celebrado en la Escuela de Arquitectura de la Universidad de Sevilla desde el 24 hasta el 26 de junio de 2015.Different methods have been used recently to discover new families of a type of space frame: Double-
Layer Tensegrity Grids (DLTGs). The main objective of this work is analyzing the process for the design
and calculation of a specific deployable DLTG (DDLTG) at full scale (4x4x1 m) composed by 16 modules
of 1x1x1 m.
Three CAD/CAE tools were used for these purposes: ToyGL, Matlab/Octave, and Midas Civil. It was
necessary to create an intermediate platform to exchange data and information between both tools,
the ToyGL Processor, based on user-defined functions written in VBA for Microsoft Excel.
The methodology was validated by comparing the results obtained by the first two software tools with
those provided by Midas Civil. As a conclusion, ToyGL is reliable and accurate in terms of the definition
of geometry, distribution of stresses and forces, reactions, states of self-stress, mechanisms, etc
Novel Technique for Obtaining Double-Layer Tensegrity Grids
Double-layer tensegrity grids (DLTGs) may be defined as
tensegrity spatial systems containing two parallel horizontal networks of
members in tension forming the top and bottom layers, whose nodes are linked
by vertical and/or inclined bracing members in compression and/or tension.
In this paper, a new approach is described. Conventional double-layer grids
(DLGs) are composed of three layers: top, bottom and bracing members. This
paper shows new rules for generating original DLGs following a recent
methodology for their composition, from the mosaic of the bracing members
and additional laws. Finally, from them, a new technique, known as Rot-
Umbela manipulation, is applied to obtain their tensegrity form, opening and
endless catalogue of DLTGs
Generation and nomenclature of tessellations and double-layer grids
The aim of this work is to establish a systematic methodology for generating automatically different tessellations and double-layer grids (DLGs) following a defined and specific nomenclature proposed originally for such a task. This particular nomenclature defines the notation of mosaics and DLGs in a synthesized and unique manner, with the advantage that it shows how to generate and design them after the parameters expressed on their own names. As a result, by means of an algorithm and some computational codes, it is possible to recreate in 3D any of those grids directly from their own names.
Current nomenclature for tessellations is also analyzed, finding severe disadvantages, such as the excessive length of their notations or their non-uniqueness character. A new nomenclature is proposed in order to define and generate consistently and unequivocally n-uniform mosaics in a consistent manner with the current nomenclature used for the Archimedean (regular and semiregular) tessellations
Quantitative evaluation of overlaying discrepancies in mobile augmented reality applications for AEC/FM
Augmented Reality (AR) is a trending technology that provides a live view of the real and physical environment augmented by virtual elements, enhancing the information of the scene with digital information (sound, video, graphics, text or geo-location). Its application to architecture, engineering and construction, and facility management (AEC/FM) is straightforward and can be very useful to improve the on-site work at different stages of the projects. However, one of the most important limitations of Mobile Augmented Reality (MAR) is the lack of accuracy when the screen overlays the virtual models on the real images captured by the camera. The main reasons are errors related to tracking (positioning and orientation of the mobile device) and image capture and processing (projection and distortion issues). This paper shows a new methodology to mathematically perform a quantitative evaluation, in world coordinates, of those overlaying discrepancies on the screen, obtaining the real-scale distances from any real point to the sightlines of its virtual projections for any AR application. Additionally, a new utility for filtering built-in sensor signals in mobile devices is presented: the Drift-Vibration-Threshold function (DVT), a straightforward tool to filter the drift suffered by most sensor-based tracking systems