Advances in modelling of biomimetic fluid flow at different scales

The biomimetic flow at different scales has been discussed at length. The need of looking into the biological surfaces and morphologies and both geometrical and physical similarities to imitate the technological products and processes has been emphasized. The complex fluid flow and heat transfer problems, the fluid-interface and the physics involved at multiscale and macro-, meso-, micro- and nano-scales have been discussed. The flow and heat transfer simulation is done by various CFD solvers including Navier-Stokes and energy equations, lattice Boltzmann method and molecular dynamics method. Combined continuum-molecular dynamics method is also reviewed

Three-dimensional printing of neuron-inspired structures by direct laser writing

Neuron-inspired structures are 2D or 3D artificial structures that emulate the structural features in biological neural networks (BNNs). Due to their inherent varied characteristics, such as geometrical characteristics, mechanical properties and biocompatibility, these neuron-inspired structures not only provide structural supports and direct neuron shapes and affect neuron differentiation, migration and proliferation in the field of neuron tissue culturing but have proved to reflect their involvement in different neuron functional tasks in neuroelectronic interfacing applications and neuromorphic computing purposes. The design, fabrication and characterisation of neuron-inspired structures has received considerable attention over the past decades, with many fabrication techniques, including electron beam lithography (EBL) and three-dimensional (3D) additive printing, utilised in fabrication of two-dimensional (2D) or 3D neuron-inspired structures. In addition, future applications of neuron-inspired structures require development in the fabrication of 3D neuron-inspired structures at the sub-micrometre scale with high biocompatibility as well as emulation of the structural features in BNNs. However, owing to the fact that BNNs possess extraordinary complexity and connectivity at the sub-micrometre scale in 3D space, traditional fabrication of neuron-inspired structures cannot emulate the complexity in BNNs. One reason is the constraints rooted in the fabrication technologies used in the fabrication of neuron-inspired structures, such as EBL, mask lithography and other recent developments in 3D fabrication techniques. These techniques are generally limited to fabrication in either 2D substrate or 3D space lacking resolution. Another reason is the lack of emulation of the structural features in BNNs. Neuron-inspired structures that have been fabricated are generally very simple, such as microholes or micro-grooves. These structures cannot emulate geometrical features such as the branching structures in BNNs. The solution lies in the combination of 3D direct laser writing (DLW), biomimetics and recently developed biocompatible hydrogel materials. 3D DLW based on two-photon absorption (TPA) is a cost-effective fabrication technique that can fabricate 3D arbitrary structures down to the 9 nm feature size. Biomimetics is a multidisciplinary field that has provided numerous solutions in the fields of physics, chemistry and engineering. In this PhD project, we propose and demonstrate the use of 3D DLW to fabricate biomimetic neuron-inspired structures with a sub-micrometre feature size. In the main, we focus on four aspects of research: 1. discovery of unique structural features in BNNs networks and mathematical definition of the corresponding structures based on biomimetics 2. investigating the challenges in the fabrication of these structures and identifying solutions to tackle these challenges using 3D DLW 3. understanding the relationship between structure and properties (such as mechanical properties) based on experimental and theoretical study, revealing the physics principles and underlying mechanisms 4. developing a biocompatible photosensitive material suitable for 3D DLW. 3D biomimetic neuron-tracing structures can be directly fabricated using 3D DLW with a sub-micrometre feature size, tenfold smaller than biological counterparts. By introducing the mathematical model behind the elastic-capillary phenomenon, stable 3D biomimetic neuron-tracing structures can be fabricated by tuning fabrication conditions such as laser power and writing speed. This work solves the fabrication challenge faced in the fabrication of 3D neuron-tracing structures at the sub-micrometre scale. Inspired by the mathematical formula for the `shortest connection distance' in BNNs, biomimetic 3D Steiner tree microstructures were introduced and fabricated using galvo-dithering DLW. The mechanical properties of the fabricated 3D Steiner tree microstructures are theoretically and experimentally studied, and the power-law scaling relationships between relative density and Young's modulus / yield strength confirmed. 3D Steiner tree microstructures have the smallest relative density compared with traditional low-density structures, rendering them potential candidates in many fields, including biomedical engineering and mechanical metamaterials. A novel biocompatible hydrogel suitable for 3D DLW for future applications in biomedical science was developed. Demonstration of the properties of our selected components were performed using z-scan methods. The range of the Young's modulus of the hydrogel material was studied by fabricating hydrogel microcubic structures with different laser powers. Further experimental fabrication and theoretical study showed the reversibility of the hydrogel microstructures resulted from the swelling and shrinking effect of hydrogels. A series of neuron-inspired fractal tree structures were fabricated using optimised conditions in the hydrogel. This chapter demonstrated the properties of the biocompatible hydrogel for 3D DLW

Towards a bio-shading system concept design methodology

Cities and buildings play a critical role in setting the conditions for human well-being while contributing to more just and environmentally conscious societies and economies. The design of environmentally and socially meaningful buildings has benefitted, in the past two decades, from scientific progress in the fields of computation and materials, as well as from a new way of looking into Nature as an inspirational example. This research focuses on the design of shading systems for building façades, assuming that biomimetics and computational design are a valid and proved combination. The main research question is how to develop architectural shading systems mimicking the adaptation strategies of Nature. The challenge is addressed by developing a design methodology for the creation and optimization of solar control systems based on the biological adaptive systems of terrestrial plants; creating a transfer and interpretation process of biological concepts to an architectural lexicon; and creating a universal methodology applicable to a diverse set of climatic, functional and local contexts. The research proposes a bioshading system design methodology, developed on a problem-based approach. Starting with the architectural challenge of design, solutions are sought in Nature to solve specific performance requirements of shading systems. The development of the methodology rests upon an informed process that integrates and interrelates three domains: architecture, Nature, and artifact. The ‘architecture’ domain is based on the conceptual process, the computational and parametric environmental analysis, and a diagnosis that informs the understanding of the performance requirements that need to be fulfilled. The ‘Nature’ domain is defined through an abstraction process: sustained by a mapping of plants’ features and adaptation strategies, the creation of a meme semantics triggers a performance-based design process. The ‘artifact’ domain is the physical materialization of the design concept, enabling its evaluation and emulation. The Nature-inspired design methodology developed in this research makes it possible for architects to solve the challenges of shading building façades, integrating local climate-related performance requirements with formal architectural criteria, using biomimicry as a mediator. In a step-by-step path, the user identifies specific project-related requirements, discovers and explores natural processes that guide inspiration, and conceptualizes a design proposal that is further simulated and prototyped.As cidades e os edifícios desempenham um papel crítico na definição das condições para o bem-estar humano, contribuindo para sociedades e economias mais justas e ambientalmente conscientes. O projeto de edifícios com significado ambiental e social beneficiou, nas últimas duas décadas, do progresso científico nos campos da computação e dos materiais, bem como de uma nova forma de encarar a natureza enquanto modelo inspirador. Esta investigação centra-se no design de sistemas de sombreamento para fachadas de edifícios, assumindo que a biomimética e o design computacional são uma combinação válida e comprovada. A principal questão de investigação é como desenvolver sistemas de sombreamento arquitetónicos mimetizando as estratégias de adaptação da natureza. O desafio é abordado através do desenvolvimento de uma metodologia de projeto para a criação e otimização de sistemas de controlo solar tendo por base os sistemas de adaptação biológicos das plantas vasculares terrestres; criação de um processo de transferência e interpretação de conceitos biológicos para um léxico arquitetónico; e criação uma metodologia universal aplicável a um conjunto diversificado de contextos climáticos, funcionais e locais. A presente investigação propõe uma metodologia de projeto de sistema bioshading, desenvolvida através de uma abordagem problem-based. Partindo do desafio arquitetónico de projeto, são procuradas soluções na natureza para resolver requisitos de desempenho específicos de sistemas de sombreamento. O desenvolvimento da metodologia tem por base um processo informado que integra e interrelaciona três domínios: arquitetura, Natureza e artefacto. O domínio 'arquitetura' tem por base o processo conceptual, na análise ambiental computacional e paramétrica e num diagnóstico que informa o entendimento dos requisitos de desempenho a serem cumpridos. O domínio 'Natureza' é definido por meio de um processo de abstração: sustentado por um mapeamento de recursos e estratégias de adaptação das plantas, a criação de uma semântica de memes desencadeia um processo de design com base no desempenho. O domínio "artefacto" é a materialização física do conceito de design, permitindo a sua avaliação e emulação. A metodologia de design inspirada na natureza desenvolvida neste trabalho de investigação possibilita aos arquitetos resolverem os desafios de sombreamento de fachadas de edifícios, integrando os requisitos locais de desempenho relacionados com o clima com critérios formais de arquitetura, usando a biomimética como mediadora. Num percurso progressivo evolutivo, o utilizador identifica requisitos específicos do projeto, descobre e explora processos naturais que orientam a inspiração e conceptualiza uma proposta de projeto que é simulada e prototipada

Three-dimensional printing of neuron-inspired structures by direct laser writing

Neuron-inspired structures are 2D or 3D artificial structures that emulate the structural features in biological neural networks (BNNs). Due to their inherent varied characteristics, such as geometrical characteristics, mechanical properties and biocompatibility, these neuron-inspired structures not only provide structural supports and direct neuron shapes and affect neuron differentiation, migration and proliferation in the field of neuron tissue culturing but have proved to reflect their involvement in different neuron functional tasks in neuroelectronic interfacing applications and neuromorphic computing purposes. The design, fabrication and characterisation of neuron-inspired structures has received considerable attention over the past decades, with many fabrication techniques, including electron beam lithography (EBL) and three-dimensional (3D) additive printing, utilised in fabrication of two-dimensional (2D) or 3D neuron-inspired structures. In addition, future applications of neuron-inspired structures require development in the fabrication of 3D neuron-inspired structures at the sub-micrometre scale with high biocompatibility as well as emulation of the structural features in BNNs. However, owing to the fact that BNNs possess extraordinary complexity and connectivity at the sub-micrometre scale in 3D space, traditional fabrication of neuron-inspired structures cannot emulate the complexity in BNNs. One reason is the constraints rooted in the fabrication technologies used in the fabrication of neuron-inspired structures, such as EBL, mask lithography and other recent developments in 3D fabrication techniques. These techniques are generally limited to fabrication in either 2D substrate or 3D space lacking resolution. Another reason is the lack of emulation of the structural features in BNNs. Neuron-inspired structures that have been fabricated are generally very simple, such as microholes or micro-grooves. These structures cannot emulate geometrical features such as the branching structures in BNNs. The solution lies in the combination of 3D direct laser writing (DLW), biomimetics and recently developed biocompatible hydrogel materials. 3D DLW based on two-photon absorption (TPA) is a cost-effective fabrication technique that can fabricate 3D arbitrary structures down to the 9 nm feature size. Biomimetics is a multidisciplinary field that has provided numerous solutions in the fields of physics, chemistry and engineering. In this PhD project, we propose and demonstrate the use of 3D DLW to fabricate biomimetic neuron-inspired structures with a sub-micrometre feature size. In the main, we focus on four aspects of research: 1. discovery of unique structural features in BNNs networks and mathematical definition of the corresponding structures based on biomimetics 2. investigating the challenges in the fabrication of these structures and identifying solutions to tackle these challenges using 3D DLW 3. understanding the relationship between structure and properties (such as mechanical properties) based on experimental and theoretical study, revealing the physics principles and underlying mechanisms 4. developing a biocompatible photosensitive material suitable for 3D DLW. 3D biomimetic neuron-tracing structures can be directly fabricated using 3D DLW with a sub-micrometre feature size, tenfold smaller than biological counterparts. By introducing the mathematical model behind the elastic-capillary phenomenon, stable 3D biomimetic neuron-tracing structures can be fabricated by tuning fabrication conditions such as laser power and writing speed. This work solves the fabrication challenge faced in the fabrication of 3D neuron-tracing structures at the sub-micrometre scale. Inspired by the mathematical formula for the `shortest connection distance' in BNNs, biomimetic 3D Steiner tree microstructures were introduced and fabricated using galvo-dithering DLW. The mechanical properties of the fabricated 3D Steiner tree microstructures are theoretically and experimentally studied, and the power-law scaling relationships between relative density and Young's modulus / yield strength confirmed. 3D Steiner tree microstructures have the smallest relative density compared with traditional low-density structures, rendering them potential candidates in many fields, including biomedical engineering and mechanical metamaterials. A novel biocompatible hydrogel suitable for 3D DLW for future applications in biomedical science was developed. Demonstration of the properties of our selected components were performed using z-scan methods. The range of the Young's modulus of the hydrogel material was studied by fabricating hydrogel microcubic structures with different laser powers. Further experimental fabrication and theoretical study showed the reversibility of the hydrogel microstructures resulted from the swelling and shrinking effect of hydrogels. A series of neuron-inspired fractal tree structures were fabricated using optimised conditions in the hydrogel. This chapter demonstrated the properties of the biocompatible hydrogel for 3D DLW

ICS Materials. Towards a re-Interpretation of material qualities through interactive, connected, and smart materials.

The domain of materials for design is changing under the influence of an increased technological advancement, miniaturization and democratization. Materials are becoming connected, augmented, computational, interactive, active, responsive, and dynamic. These are ICS Materials, an acronym that stands for Interactive, Connected and Smart. While labs around the world are experimenting with these new materials, there is the need to reflect on their potentials and impact on design. This paper is a first step in this direction: to interpret and describe the qualities of ICS materials, considering their experiential pattern, their expressive sensorial dimension, and their aesthetic of interaction. Through case studies, we analyse and classify these emerging ICS Materials and identified common characteristics, and challenges, e.g. the ability to change over time or their programmability by the designers and users. On that basis, we argue there is the need to reframe and redesign existing models to describe ICS materials, making their qualities emerge

Exploring the role of digital technology in enhancing an environmentally responsive architecture: toward a fog water harvesting and visitors centre on Signal Hill

Master of Architecture. University of KwaZulu-Natal, DurbanThe development and progression of architecture throughout the ages has been for the most part as a result of the influence of new technologies. Today, more environmentally responsible and innovative buildings are being constructed thanks to research and developments in technology. As the information age transforms into the digital age, the trend for digital integration into every-day life is becoming the norm. Concurrently, the promotion of sustainable living in our society has been facilitated by digital technology. While digital technology and sustainable living might seem like completely different fields, they are more interconnected than we may believe. This dissertation explores how digital technology can enhance an environmentally responsive architecture. The thesis provides principles for developing a connection between digital technology and environmental architecture in order to facilitate a sustainable approach toward sourcing water

Meta-parametric design: Developing a computational approach for early stage collaborative practice

Computational design is the study of how programmable computers can be integrated into the process of design. It is not simply the use of pre-compiled computer aided design software that aims to replicate the drawing board, but rather the development of computer algorithms as an integral part of the design process. Programmable machines have begun to challenge traditional modes of thinking in architecture and engineering, placing further emphasis on process ahead of the final result. Just as Darwin and Wallace had to think beyond form and inquire into the development of biological organisms to understand evolution, so computational methods enable us to rethink how we approach the design process itself. The subject is broad and multidisciplinary, with influences from design, computer science, mathematics, biology and engineering. This thesis begins similarly wide in its scope, addressing both the technological aspects of computational design and its application on several case study projects in professional practice. By learning through participant observation in combination with secondary research, it is found that design teams can be most effective at the early stage of projects by engaging with the additional complexity this entails. At this concept stage, computational tools such as parametric models are found to have insufficient flexibility for wide design exploration. In response, an approach called Meta-Parametric Design is proposed, inspired by developments in genetic programming (GP). By moving to a higher level of abstraction as computational designers, a Meta-Parametric approach is able to adapt to changing constraints and requirements whilst maintaining an explicit record of process for collaborative working

Two decades of Martini:Better beads, broader scope

The Martini model, a coarse-grained force field for molecular dynamics simulations, has been around for nearly two decades. Originally developed for lipid-based systems by the groups of Marrink and Tieleman, the Martini model has over the years been extended as a community effort to the current level of a general-purpose force field. Apart from the obvious benefit of a reduction in computational cost, the popularity of the model is largely due to the systematic yet intuitive building-block approach that underlies the model, as well as the open nature of the development and its continuous validation. The easy implementation in the widely used Gromacs software suite has also been instrumental. Since its conception in 2002, the Martini model underwent a gradual refinement of the bead interactions and a widening scope of applications. In this review, we look back at this development, culminating with the release of the Martini 3 version in 2021. The power of the model is illustrated with key examples of recent important findings in biological and material sciences enabled with Martini, as well as examples from areas where coarse-grained resolution is essential, namely high-throughput applications, systems with large complexity, and simulations approaching the scale of whole cells. This article is categorized under: Software > Molecular Modeling Molecular and Statistical Mechanics > Molecular Dynamics and Monte-Carlo Methods Structure and Mechanism > Computational Materials Science Structure and Mechanism > Computational Biochemistry and Biophysics

An Exploration into Biomimicry and its Application in Digital & Parametric [Architectural] Design

Biomimicry is an applied science that derives inspiration for solutions to human problems through the study of natural designs, systems and processes. This thesis represents an investigation into biomimicry and includes the development of a design method based on biomimetic principles that is applied to the design of curved building surfaces whose derived integral structure lends itself to ease of manufacture and construction. Three design concepts are produced that utilize a selection of natural principles of design outlined in the initial biomimetic investigation. The first design visualizes the human genome as a template on which the process of architectural design and construction can be paralleled. This approach utilizes an organizational structure for design instructions, the adherence to an economy of means, and a holistic linking of all aspects of a design characteristic of the genetic parallel. The advancement of the first design concept is illustrated through the use of a particular form of parametric design software known as GenerativeComponents. The second design concept applies the biomimetic design approach outlined in concept one to the development of ruled surfaces with an integral structure in the form of developable flat sheets. The final concept documents the creation of arbitrary curved surfaces consisting of an integral reinforcing structure in the form of folded sheet chevrons

Design behaviors : programming the material world for responsive architecture

The advances of material science, coupled with computation and digital technologies, and applied to the architectural discipline have brought to life unprecedented possibilities for the design and making of responsive, collectively created and intelligent environments. Over the last two decades, research and applications of novel active materials, together with digital technologies such as Ubiquitous Computing, Human-Computer Interaction, and Artificial Intelligence, have introduced a model of Materially Responsive Architecture that presents unique possibilities for designing novel performances and behaviors of the architectural Beyond the use of mechanical systems, sensors, actuators or wires, often plugged into traditional materials to animate space, this dissertation proves that matter itself, can be the agent to achieve monitoring, reaction or adaptation with no need of any additional mechanics, electrical or motorized systems. Materials, therefore, become bits and information uniting with the digital world, while computational processes, such as algorithmic control, circular feedback, input or output, both drive and are driven by the morphogenetic capacities of matter, uniting, therefore, with the material world. Through the applications and implications of Materially Responsive Architecture we are crossing a threshold in design where physicality follows and reveals information through time and through dynamic configurations. Design is not limited to a finalised form but rather associated to a performance, where the final formal outcome consists in a series of animated and organic topologies rather than static geometries and structures. This new paradigm, is referred to, in this thesis, as the Design Behaviors paradigm (in the double sense of "behaviors of design" and "designing behaviors"), and is characterized by unique exchanges and dialogues between users and the environment, facilitated by the conjunction of human, material and computational intelligence. Buildings, objects and spaces are able to reconfigure themselves, in both atomic and macro scale, to support environmental changes and users' needs, behavioral and occupational patterns. At the same time the Design Behaviors paradigm places not only matter and the environment at the center of design and morphogenesis, but also the users, that become active participants of their built environment and play the final creative role. This paradigm shift, boosts new relations among the human's perception and body and the inhabited space. The new design paradigm is also a new cultural one, in which statics, repetition and Cartesian grids, traditionally related with safety, orientation and comfort, give way to motion, unpredictability and organic principles of evolution. Materially Responsive Architecture and the Design Behaviors paradigm define uniquely enhanced "environments" and "ecologies" where human, nature, artifice and technology collectively and evolutionally co-exist within a framework of increased consciousness and awareness. This thesis argues that, while there is no doubt that our future cities will consist in an extensive layer of distributed sensors, actuators and digital interfaces, they will also consist in an additional layer of novel materials, that are dynamic and soft, rather than rigid and hard, able to sense as sensors, actuate as motors, and be programmed as a software. The new materiality of our cities relies on the advances of material science, coupled with the cybernetic and computational power, and can be actuated by the environment to change states (Re-Active Matter), can be controlled by the users to respond (Co-Active Matter), and eventually can be designed and programmed to learn and evolve as living organisms do (Self-Active Matter). The physical space of the city is, thus, the seamless intertwining of digital and material content, becoming an active agent in the dynamic relationship between the environment and humans.Los avances en la ciencia de los materiales, junto con la computación y las tecnologías digitales, y aplicados a la disciplina arquitectónica, han dado vida a posibilidades sin precedentes para el diseño y la realización de entornos responsivos, inteligentes y creados de forma colectiva. En las últimas dos décadas, la investigación y aplicación de nuevos materiales activos junto con tecnologías digitales como la Computación Ubicua, la Interacción Hombre-Ordenador y la Inteligencia Artificial, han introducido el modelo de Materially Responsive Architecture (Arquitectura Materialmente Responsiva), que presenta posibilidades únicas para el diseño de nuevas actuaciones y comportamientos del espacio arquitectónico. Más allá del uso de sistemas mecánicos, sensores, o motores, a menudo conectados a materiales tradicionales para activar el espacio, esta disertación demuestra que la materia en sí misma puede ser el agente que consiga monitoreo o reactividad sin necesidad de añadir ningún sistema mecánico o eléctrico. Los materiales, en este caso, se convierten en bits e información fundiéndose con el mundo digital, mientras que los procesos computacionales, como el feedback circular y el input o output, a la vez impulsan y son impulsados por la capacidad morfogenética de la materia, uniéndose, por lo tanto, con el mundo material. A través de las aplicaciones y las implicaciones de la Materially Responsive Architecture, estamos cruzando un umbral en el diseño donde el mundo físico sigue y revela información a través de configuraciones dinámicas en el tiempo. El diseño no se limita a una forma finalizada, sino se relaciona a una performance, donde el resultado formal final consiste en una serie de topologías orgánicas y animadas en lugar de estructuras y geometrías estáticas. En esta tesis doctoral, este nuevo paradigma se denomina paradigma de Design Behaviours (en el doble sentido de "comportamientos de diseño" y de "diseño de comportamientos") y se caracteriza por intercambios únicos entre el usuario y el entorno, facilitados por la conjunción de inteligencia humana, material y computacional. Los edificios, objetos y espacios pueden reconfigurarse a sí mismos, tanto a nivél atómico como a macro escala, para responder a los cambios ambientales y a las necesidades de los usuarios. Al mismo tiempo, el paradigma Design Behaviors coloca en el centro del diseño y la morfogénesis no solo la materia y el medio ambiente, sino también a los usuarios, que se convierten en participantes de su entorno construido y desempeñan el papel creativo final. El nuevo paradigma define "entornos" y "ecologías" aumentados de manera singular, donde el ser humano, la naturaleza, el artificio y la tecnología coexisten de manera colectiva y evolutiva dentro de un marco de mayor conciencia consciente. El nuevo paradigma de diseño es también un nuevo paradigma cultural, en el que las redes estáticas, repetitivas y cartesianas, tradicionalmente relacionadas con la seguridad, la orientación y el confort, dan paso al movimiento, la imprevisibilidad y la evolución orgánica. Esta tesis sostiene que, si bien no hay duda de que nuestras ciudades futuras consistirán en una capa extensa de sensores distribuidos e interfaces digitales, también contarán con una capa adicional de materiales dinámicos y suaves, en lugar de rígidos y duros, capaces de sentir como sensores, actuar como motores y ser programados como un software. La nueva materialidad de nuestras ciudades puede ser activada por el medio ambiente para cambiar su estado (Re-Active Matter), puede ser controlada por los usuarios para responderles (Co-Active Matter), y eventualmente puede diseñarse y programarse para aprender y evolucionar por sí misma así como lo hacen los organismos vivos (Self-Active Matter). El espacio físico de la ciudad es, por lo tanto, el entrelazado holístico entre contenido digital y material, convirtiéndose en un agente activo en la relación dinámica entre el medio ambiente y los humanos