Structural Optimization of Deploying Structures Composed of Linkages

Abstract

Determining the global shape of a deploying structure and the section profiles of its members is a challenging design problem. Geometry, meaning the lengths and relative angles of members, is critical to achieving stable deployment to a desired span, while the design must also satisfy structural capacity demands at each stage of deployment. This paper explores the potential role of formal structural optimization in designing feasible and structurally efficient deploying steel structures composed of linkage elements. Both stochastic search and gradient-based algorithms are used to explore the design space and identify minimum weight solutions that satisfy kinematic and structural constraints. The proposed methodology is tested on the case study of a deploying pantograph. This strategy has the potential to be implemented for a wide range of deploying structures, including retractable roofs, rapidly expandable shelters, deploying space structures, and movable bridges. (C) 2014 American Society of Civil Engineers.