A multi-step force–density method and surface-fitting approach for the preliminary shape design of tensile structures

The aim of this paper is to introduce a new method for the conceptual design of fabric tensile structures. The proposed method combines a structural form-finding technique with a surface-fitting approach to obtain preliminary shapes of tensile structures in real time. Currently, there is a lack of adequate computer-based tools for designers involved in the first stages of the design of tensile structures. Easy graphic interfaces are needed in which the designer has the possibility of varying the shape of the membrane and the environment around it in real time to obtain different design alternatives rapidly. The paper presents a multi-step force–density method which allows the possibility of equilibrium shapes with smooth stress distribution to be obtained. Moreover, the use of parametric surfaces (NURBS) to represent tensile structures provides a significant contribution to the real-time objective. A computer application has been built to test the proposed methods, and the results are shown in this paper through different examples.