Hygro_responsive structure humidity responsive material system design

Responsive system is a method that is used to enhance buildings' environmental performance and ensure user comfort by enabling the buildings to adjust to changeable environmental circumstances. The system detects environmental changes via specific sensors, determines the action to be taken against current conditions via its control mechanism and responds to environmental changes through its actuators by changing the physical form of system components. In current use, responsive systems utilize energy-activated mechanical components such as sensors, actuators and microcontrollers; the dependency to which births the need for continuous energy supply and periodical maintenance. Motivated from the problems that are probable to be encountered at the use of mechanical responsive systems, this thesis researches how responsiveness can be achieved without the utilization of mechanical components. In nature, responsiveness is acquired in material level without any energy consumption. Wood for instance, a natural material, responds to humidity alterations without any mechanical support. The design of mechanical systems however, tends not to take the potential of natural material into consideration. Thus, this thesis study focuses on ways through which responsiveness can be achieved via a material based design. Material based responsive design employs material-inherent properties in ensuring system responsiveness and eliminates the utilization of mechanical components. Concentrating on wood as a natural material, this thesis study aims to explore the material based responsive system design through examining the inherent properties of wood material. Wood transforms its shape in response to humidity changes: It swells or shrinks in grain direction. Hygroscope and Anisotropy are the keywords in this scope; these terms represent the inherent material properties that provide responsiveness. Therefore, towards taking advantage of material properties in ensuring responsiveness, this study develops a specific composite material that possesses the hygromorphic properties of wood. The composite material employs wood as the active layer and polymer as the passive layer. The active wood layer responds to humidity and elongates due to its hygroscope-derived characteristics. The passive polymer on the other hand does not respond to humidity and remains stable. The polymer layer provides a constraint for the hygroscopic elongation of the wood layer and results the wood to bend. In this thesis study, the responsive behavior of the composite material is examined in a controlled environment through material experiments. The main objective of these experiments is to evaluate the humidity-driven behavior of the material and to improve the material performance through calibration of specific parameters such as wood types, polymer types, grain direction, fiber frequency in polymer and layer thickness. Conducted experiments are analyzed through empirical (observational) and numerical (quantitative) analysis methods. The empirical method observes the curvature change of the composite material and conducts a responsiveness comparison through a response graph. The numerical method on the other hand, enables the observational analysis results to be justified through calculations. The material experiments are carried out in a collaborative work. The collaboration of the two methods ensures the development of simplified humidity box, the production of composite material and the numerical evaluation of material experiments. The material based responsive system, introduced as the "Hygro_Responsive Structure" integrates responsive material with 'parametric structure'. The parametric structure is included in the approach considering the sunlight as a specific parameter, since sunlight has influence on relative humidity. The parametric design and the construction process of the structure are achieved through computational design tools. The sunlight analysis is conducted via Ladybug and the form development, which actually is based on sunlight analysis, is carried out via Grasshopper. The responsive material design experiments both the form of the system and the material itself; on the basis of environmental parameters. Humidity is the response driver for the material and sunlight is the design driver for the system's parametric form generation. The composite material, the main actor of the structure, is utilized in form of humidity-responsive panels. The responsive panels adapt to alterations in humidity by changing shape. The composite material utilize hygroscope in the wood material to achieve responsiveness, thus the responsive material system needs neither energy nor mechanical components to work. As a result, the material based responsive system developed in this thesis study can be introduced as an energy-efficient system. The main objective of this study is to employ material behavior in responsive architecture. Material based responsive systems can consist of an alternative to mechanically responsive systems in scope of design strategies.