Software defines Hardware – Topology of control systems for retractable roofs

Abstract

The scientific understanding of tensile technology in late XX century has arguably revolutionized the engineering design and the construction methods of structures with cables, ropes and tension rods. Adding envelope cladding with modern materials like membranes or ETFE foils large wide span structures are now achievable. The sheer size of wide span structures impacts also the electrical control systems required, as the digital world also is moving forward. While the electrical concepts of light systems are already commonly used for wide span structures, the drive systems for retractable roofs are still considered conservative as safety aspects have a high impact on these special drive systems. Nevertheless, the development of sophisticated communication languages, enhanced safety protocols in combination with outdoor suited hardware allows new control designs for drive systems of retractable roofs. Furthermore, the use of state of the art components like the latest generation of frequency controller and sensors using bus communication allow the development of safe and economical control systems on wide span structures. Two examples of different control system topologies are presented here with decentralized control topology of the retractable roofs at the SOFI stadium in Inglewood, US and the centralized control system topology at the Al Janoub Stadium in Al Wakrah, Qatar. SOFI Stadium uses a complete decentralized control system topology. With “Net” based co mmunication protocols and electrical components with “Net” interface” a communication network can be introduced between the active elements on the wide span structure. The freedom provided by the software of choosing the right hardware allows the optimization of the whole system under different topics like available space for electrical components, wiring, accessibility, maintenance and fast installation. The Al