THE SWIVEL DIAPHRAGM: a geometrical examination of an alternative retractable ring structure
ABSTRACT
Since ancient times, deployable structures have been applied in architecture for a wide range of purposes. Over the last four decades, substantial scientific research regarding the structural and kinematical characteristics of these structures has been carried out. With advances in technology and the invention of stronger materials, new applications, for example retractable roofs and transformable enclosures have become possible. Several systems come under the classification of deployable structures. The present research focuses on the study of one group of structures named deployable lattice structures with rigid links [DLSRL]. These structures are formed mainly by rigid elements (i.e. bars or plates) linked by hinges that allow them to transmit movement from one element to the next. R indicates that the demand for buildings with deployable structures such as DLSRL appears to be on the increase, particularly in applications like retractable roofs or transformable enclosures. However, to date, built architectural projects have been quite limited. Possible reasons for this are, that there may be a of these type of structures, specialised literature on the subject is not widely available within the design sphere,
the existing systems may be very complex and not completely appropriate for architectural purposes. This thesis seeks to explore the last two possible reasons mentioned above. One of the main aims of this work is to develop alternative simpler systems, based on those already existing, that could potentially be easier to use within architecture.
Since ancient times, deployable structures have been applied in architecture for a wide range of purposes. Over the last four decades, substantial scientific research regarding the structural and kinematical characteristics of these structures has been carried out. With advances in technology and the invention of stronger materials, new applications, for example retractable roofs and transformable enclosures have become possible. Several systems come under the classification of deployable structures. The present research focuses on the study of one group of structures named deployable lattice structures with rigid links [DLSRL]. These structures are formed mainly by rigid elements (i.e. bars or plates) linked by hinges that allow them to transmit movement from one element to the next. R indicates that the demand for buildings with deployable structures such as DLSRL appears to be on the increase, particularly in applications like retractable roofs or transformable enclosures. However, to date, built architectural projects have been quite limited. Possible reasons for this are, that there may be a of these type of structures, specialised literature on the subject is not widely available within the design sphere,
the existing systems may be very complex and not completely appropriate for architectural purposes. This thesis seeks to explore the last two possible reasons mentioned above. One of the main aims of this work is to develop alternative simpler systems, based on those already existing, that could potentially be easier to use within architecture.
This work includes a historical background of the existing DLSRL systems, followed by a more detailed exploration of retractable ring structures. Retractable ring structures were chosen for further study since they showed more possibilities of variations that could potentially serve to create new systems. Computer generated and physical models were used to experiment with different morphological and geometrical configurations and retractable ring structures. As a result of this exploration, a new type of retractable ring structure, named: the ‘Swivel Diaphragm’, was proposed. Compared with existing DLSRL systems, the Swivel Diaphragm showed
improved characteristics, such as the option of fixed in position supports and interconnection between components. The Swivel Diaphragm was developed further, thus yielding two sub-systems: the ‘peripheral swivel diaphragm’ and the ‘central swivel diaphragm’. It was found that by interconnecting a series of swivel diaphragms within grids, a large range of designs with different deployment qualities were possible. In so doing, five methods of interconnecting in two and three dimensions, based on geometrical tessellations, were proposed. The resulted grid structures showed to have great potential for application within transformable devices for building
surfaces. To illustrate this potential, five hypothetical design solutions using the swivel diaphragm within kinetic canopies, transformable enclosures and a retractable roof were suggested.
It is considered by the author that the present thesis contributes to the existing knowledge of deployable structures by offering an alternative type of retractable ring structure that shows applicability for architectural purposes. This work presents a detailed explanation of how to manipulate the geometrical and morphological characteristics of the swivel diaphragm in order to adapt it to desired design conditions. Showing the flexibility and simplicity of the proposed systems aims to motivate or inspire designers and clients to consider their use in architecture. This work seeks to be of particular interest for audiences related with architecture, industrial design, civil engineering, mechanical engineering and geometry.
Key words: transformable, kinetic, retractable, foldable, unfoldable, dismountable and
convertible structures.
convertible structures.
