Implementation of bending-active elements in kinematic form-active structures - Part I : design of a representative case study

Due to their low self-weight and their inherently high flexibility, technical textiles offer great possibilities for the integration in kinematic structures. Furthermore, the implementation of active bending in a transformable design creates new challenging perspectives. The paper describes an integrated approach for transformable textile hybrids where an improved design is obtained through a parameter study, performing a structural analysis in the different phases of the deployment. The studied parameters include (i) the form-finding position, (ii) the prestress (ratio), (iii) the used materials and sections (including the fibre directions) and (iv) the number of bending-active elements. This research confirms the feasibility of realizing kinematic form-active structures with integrated bending active elements, where both the membrane and the supporting structure are stable in the different configurations. Due to the high interaction between the bending-active supporting system and the pretensioned membrane, the different parameters influence each other significantly. In a next step, an experimental verification of the designed pringle-shaped textile hybrid is carried out in order to both confirm the possibilities and reveal the remaining challenges