Computational tools for designing shape- changing architectures

Smart materials or systems are characterized by having built-in sensors and actuators, adjusting their properties in response to external stimulus. The rapid development of these technologies presents an immense opportunity for designers and architects to provide innovative and creative solutions for adaptive buildings. However, there are several challenges for the incorporation of smart materials in the toolbox of architects in design practice: The lack of an overlap in knowledge between material science fields and design practices; the addition of time as a condition that renders these materials inherently dynamic; and the general disconnect between material issues in typical design settings. This paper discusses the challenges for designing shape-changing architecture and examines the way in which computational tools or digital technologies can help overcome those limitations in design practice. Finally, we discuss an approach for designing shape changing architectures with the aid of digital technologies, highlighting the different considerations that must be taken into account

Características higroscópicas de ocho maderas mexicanas

The objective of the research was to determine the basic density, the initial moisture content, the maximum moisture content, the fiber saturation point, the cell wall percentage and the void space percentage of eight Mexican woods: Cupressus lindleyi, Cedrela odorata, Swietenia macrophylla, Tabebuia donnell-smithii, Fraxinus uhdei, Fagus mexicana, Dalbergia palo-escrito and Guazuma ulmifolia. The variability of the hygroscopic characteristics of the woods studied can be explained by the differences in the anatomical characteristics of each species. However, their magnitudes are within the ranges reported in the bibliography.El objetivo de la investigación fue determinar la densidad básica, el contenido de humedad inicial, el máximo contenido de humedad, el punto de saturación de la fibra, el porciento de pared celular y el porciento de espacios vacíos de ocho maderas mexicanas: Cupressus lindleyi, Cedrela odorata, Swietenia macrophylla, Tabebuia donnell-smithii, Fraxinus uhdei, Fagus mexicana, Dalbergia palo-escrito y Guazuma ulmifolia. La variabilidad de las características higroscópicas de las maderas estudiadas puede explicarse por las diferencias en las particularidades anatómicas propias de cada especie. Sin embargo, sus correlaciones estadísticas, así como sus magnitudes se sitúan en los rangos reportados en la bibliografía

SMP Prototype Design and Fabrication for Thermo-responsive Façade Elements

The aim to attain sustainability in the built environment introduced the innovative application of advanced material technologies for low-energy, but aesthetically intriguing, building design strategies. Adaptive and responsive building skins as embedded and intrinsic control systems can be delivered with smart materials, and thus have the potential to minimise the energy consumption of buildings by maximising the natural and passive adjustment of façade components for shading, air-flow, daylight, and view. The dynamic smart material façade, adaptable to changing outdoor environments, is considered to be a holistic design approach that integrates the behavioural performance effects with the appearance and aesthetics of kinetic ability provided by smart materials acting as actuators, by adjusting their properties according to external stimuli. Of the various environmental inputs sensed by, and actuating, active and dynamic building façade systems, this research focuses on temperature as the stimulus to activate a dynamic shading device with the mechanism of opening and closing, specifically considering Seoul’s climate. Among currently available thermo-responsive smart materials, the shape memory polymer (SMP) is investigated as an activator of shading devices to be implemented to adaptive building skin strategies. As the first stage of SMP prototype design and fabrication study toward the thermo-responsive building façade elements, SMP prototypes are proposed in cell types. Among the general thermo-mechanical cycle of thermo-responsive SMP, only programming of the permanent shape via additive manufacturing and recovery at the activation temperature are focused upon in this research. This study proposes a design-to-fabrication workflow integrating computational tools, 3d printing and recalibration of relevant variables in digital design process, G code generation, and manufacturing using commercially available SMP filaments. To verify the 3d printing process, and to demonstrate the shape-changing behaviour of SMP actuators, reproduction of a referenced prototype was conducted, in addition to fabrication experiments of SMP surfaces with various thicknesses and SMP hinges with customised rotating angles. In addition, a base-line prototype combining the static ABS plate and the active SMP hinge is developed to set up the heat test and a digital motion simulation from data of shape changing behaviour acquired from a hands-on model test. After the demonstration of the baseline prototype in design and additive manufacturing process, various SMP prototypes were designed with reference to kinetic prototype researches, but with the consistent 100mm-diameter circular surface, in a scale of 1:3. They were also fabricated with a 3d printer for both open and closed positions to testify to their constructability, and thus to comparatively evaluate the design and fabrication outcomes. Furthermore, after conducting radiation and thermal simulation analysis, shading performance validation is noted for selecting potential prototypes. Lastly, the needs to further develop reversible reiterative shape-changing materials or systems are briefly discussed

Shape-changing architectural skins: a review on materials, design and fabrication strategies and performance analysis

In recent years, there has been an increasing interest in shape-changing smart materials in design fields. The ability to design responsive architectures that adapt to different climatic conditions is, without doubt, an appealing idea. One area in which shape-changing materials are applied is in the design of building skins or envelopes. This paper presents a systematic review of the literature on the use of shape-changing materials in the development of active skin systems, identifying patterns in design and manufacturing strategies. We also note the stage of development of the proposed designs and whether performance analysis was conducted to predict their behaviour. The results show that the most commonly used materials are SMA (Shape Memory Alloys) and wood-based bio-composites. Other shape-changing materials used for developing skin systems are, in order of popularity, thermo bimetals, electroactive polymers, composite bimetals, shape memory polymers, and hydrogels. The patterns identified among the studies are (1) design strategies: smart material as the skin, smart material as the actuator, combination with other non-responsive materials, responsive structures, geometric amplification; and (2) manufacturing strategies: bilayer systems and additive manufacturing.   Finally, while the argument for the development of responsive skin systems is often based on the idea of efficiency and improved performance, we found that few studies can predict the performance of such skin systems

Higroexpansión, higrocontracción y sus relaciones de anisotropía de ocho maderas mexicanas

El objetivo de la investigación fue determinar los coeficientes de higroexpansión, de higrocontracción y sus relaciones de anisotropía de ocho maderas mexicanas: Cupressus lindleyi, Cedrela odorata, Swietenia macrophylla, Tabebuia donnell-smithii, Fraxinus uhdei, Fagus mexicana, Dalbergia palo-escrito y Guazuma ulmifolia. Se realizaron pruebas de higroscopía con un procedimiento de humidificación y secado de probetas de pequeñas dimensiones. Las magnitudes de las higroexpansiones e higrocontracciones son similares a las de otras especies mexicanas reportadas en la literatura. Los coeficientes denotan un carácter anisotrópico en las direcciones radial y tangencial. La densidad de la madera es un buen predictor de los coeficientes. Sin embargo, las correlaciones de las relaciones de anisotropía son diferentes a las reportadas en trabajos anteriores. DOI: https://doi.org/10.54167/tecnociencia.v16i1.86

A multi-physics approach for modeling hygroscopic behavior in wood low-tech architectural adaptive systems

Wood is a natural engineering material that has traditionally been exploited in design for a wide variety of applications. The recent demand for sustainable material and construction processes in the construction industry has triggered a renewed interest and research in the inherent properties of wood and their derived applications, and specifically for developing low-tech architectural adaptive systems. This paper focuses on the physical and computational modeling of the morphing behavior of wood through hygroscopic expansion or contraction to a high degree of precision. The amount of stress related to the hygroscopic shrinking or swelling ranges from almost zero to high values, and its prediction is fundamental to alleviate any fatigue challenges. The capability of designing wood composite whose stress state remains limited under changes of the environmental humidity is beneficial for any engineering application subjected to a repeated reversal of loading such as adaptive systems. In this paper, a mechanical model, together with its numerical implementation, is presented; the model is benchmarked against some prototypical experiments, performed by using real material parameters. The control parameter in the model is the relative moisture change in wood that determines the orthotropic swelling/de-swelling phenomenon, and is coupled with the elastic behavior of wood. This model is integrated into a programmable matter design approach that combines physical and computational exploration. The approach is illustrated for a hygro-morphic building façade panel. The approaches and algorithms presented in this paper have further applications for computer-aided design of smart materials and systems with interchanging functionalities

Adaptación de un sistema de fachada multicapas utilizando como componente de revestimiento madera tratada térmicamente a una edificación con tipología constructiva BALLOON FRAME para mejorar su eficiencia energética y habitabilidad en la ciudad de Mollendo, Arequipa - Perú 2021

La eficiencia energética en la proyección de edificios es una variable poco desarrollada y valorada en la arquitectura peruana del día a día, esto sumado a una normativa nacional aún incipiente, genera una poca comprensión sobre la importancia de la habitabilidad y confort térmico, el consumo energético y los materiales biodegradables. Por ello la presente investigación tiene como objetivo comparar la aplicación de un sistema de fachada multicapas con un sistema balloon frame típico de la arquitectura costera de la ciudad de Mollendo, a través del análisis de variables como el coeficiente de transmisión térmica de los muros opacos de la edificación, la investigación del micro y macro clima y el estudio de las propiedades físicas de un material biodegradable como la madera tratada térmicamente. A través de un diseño metodológico de tipo experimental, se identificó los agentes atmosféricos de la ciudad de Mollendo a través del método de Scheffer, el grado de conservación del sistema balloon frame original mediante los estándares de la norma europea UNE-EN 335:2013, se determinó las propiedades físicas de la madera tratada térmicamente mediante normas ASTM e ISO, se establecieron variables de diseño del sistema de fachada multicapas (geometría del elemento, componentes de capas y resistencias térmicas) para finalmente validar el sistema propuesto a través de la metodología del Código Técnico de Edificación DB-HE y el software THERM. Los resultados mostraron que el factor de severidad climática para la casa de estudio en Mollendo se clasifica como “Severo”, significando la necesidad de una rehabilitación del edificio, respecto a la madera tratada térmicamente de la especie Tornillo, el coeficiente de absorción de agua se redujo en 73 % (lo que significa una mayor facilidad al momento de emplearlo), sus niveles de anisotropía se redujeron en un 26 % (representando una categoría de “muy estable” para trabajos de construcción); asimismo se observó una mejor textura y color y finalmente el v valor de transmitancia térmica del muro opaco del sistema balloon frame propuesto fue de 0.50 W/m2K. Este valor es más que adecuado a lo solicitado por el Código Técnico de Edificación para una zona climática como la de Mollendo, significando la mejora en el confort térmico dentro de la vivienda en temporadas lluviosas o de invierno.Tesi

Proceedings of the 9th Arab Society for Computer Aided Architectural Design (ASCAAD) international conference 2021 (ASCAAD 2021): architecture in the age of disruptive technologies: transformation and challenges.

The ASCAAD 2021 conference theme is Architecture in the age of disruptive technologies: transformation and challenges. The theme addresses the gradual shift in computational design from prototypical morphogenetic-centered associations in the architectural discourse. This imminent shift of focus is increasingly stirring a debate in the architectural community and is provoking a much needed critical questioning of the role of computation in architecture as a sole embodiment and enactment of technical dimensions, into one that rather deliberately pursues and embraces the humanities as an ultimate aspiration