The Architecture of the Future: Kinetic Structures and Mashrabiya-Based Facade Design

Mashrabiya Tabanlı Cephe Tasarımı

Abstract

Advances in robotics, materials science, computer science, and building technology have begun to change architecture. With kinetic architecture beginning to shape the future of architecture, flexible and adaptive design solutions have been developed to respond to the changing spatial needs and climatic conditions. There is a dynamic interaction between people and space in kinetic architecture, whereas the movement in conventional buildings is limited to the space we are in. Kinetic structures allow the reshaping of space according to user movement or need.

Kinetic structures can be integrated into existing buildings as roof or façade elements or used in temporary functions as self-standing structures. Because they can transform from a compact state to an expanded form, they can be moved to different locations at their compact configurations and reused for various functions. Facade systems that can change their shapes in response to weather conditions, shelters that are rapidly assembled and removed in emergencies, movable pedestrian bridges, and retractable roofs of large-span structures such as stadiums and concert halls are among the application areas. Kinetic structures provide many advantages compared to conventional systems as they can change their shapes rapidly according to the changing climatic conditions and user needs, reduce the cooling loads of buildings, and easily be transported to different places. Therefore, the application areas of kinetic structures have increased in recent years.

Kinetic structures can move by rotating, sliding, folding or deforming, which can be reviewed under five categories: rigid bar structures (scissor and bar structures), foldable plate structures, membrane structures, pneumatic structures and material-based systems. When those are compared, it can be said that scissor structures and pneumatic structures are widely used for temporary functions because they can be assembled and removed quickly and be easily transported to the desired locations in their compact forms. Membrane structures can offer practical solutions for large-span. On the other hand, foldable plate structures and material-based systems are often encountered in kinetic facades. Although different structural systems and geometric methods are used when developing kinetic structures, the main aim is to respond rapidly to changing conditions and needs.

In kinetic architecture, which is at the interface between engineering and architecture, the structure is shaped according to the movement; therefore, the geometry of motion and corresponding mechanism must be designed first to obtain the desired form at the final geometric configuration of the structure. Within this context, first, the types of motion and the joints used in kinetic structures have been introduced in this paper. Then, the examples of kinetic structures have been examined for their morphological and kinematic properties, and how they shape the space according to the changing circumstances has been discussed. Finally, the kinetic façade developed based on the geometric tessellation method has been presented.

Regular, semi-regular and demi-regular tessellations or Mashrabiya patterns frequently encountered in Islamic architecture can be used in kinetic façade design. In this paper, the Mashrabiya pattern with a hexagonal based star shape has been chosen for the kinetic façade design. First, the hexagonal-shaped sub-module consisting of isosceles triangular elements has been created. The sub-module can retract from the center to the periphery with single-degree-of-freedom. To investigate the potentials of the Mashrabiya pattern, the sub-module has been replicated by linear iteration along -x and -y directions and by radial iteration around the sub-module. Each module can move independently of the other modules. This is because of the increased number of elements and joints in the kinetic system. The kinematic behavior of the system allows generating of different geometric configurations with the same module. While some of the modules can remain at their fully closed configurations, others can move alternately.

After presenting alternative geometric configurations of the kinetic systems generated by linear and radial iterations and discussing their movement capabilities, the proposed kinetic façade system has been introduced, which is composed of hexagonal modules moving separately on a grid frame structure. Transforming from a star-like shape to a hexagonal shape and then to a circular form, the hexagonal module can open and close to control daylight and reduce solar heat gain. Since the elements of the module retract by making linear movement along the diagonals of the hexagon, the independent movement of the modules can easily be controlled using linear actuators attached to the frame structure.

Because the proposed kinetic system has form flexibility, it can be applied to any glazed façade as a second layer to respond to changing conditions and fulfill the functions such as shading and natural ventilation. The kinetic façade proposal can be used as a guide for the development of alternative design solutions based on the tessellation method. Since kinetic facades play a significant role in energy-efficient building design, they will become more applicable in the near future with the developments in technology.