Evaluation of design parameters for deployable planar scissor arches

Deployable scissor structures can transform from a compact bundle of elements to a fully expanded configuration. Due to this transformational capacity there is a mutual relation between the geometry, the kinematics and the structural response of the scissor system, resulting in a relatively complex design process. In order to understand how geometrical parameters influence the structural performance, it is beneficial to evaluate these structures at a pre-design stage. To reach this goal, we developed an integrated framework for pre-design evaluation using the parametric finite element tool Karamba in combination with Matlab. By doing so an automatic and immediate preliminary structural evaluation can be established that guides the designer in making efficient geometrical design decisions. This paper evaluates design parameters for deployable scissor arches using this framework. More specifically, the influence of the most important geometrical inputs - scissor type, number of scissor units, structural thickness and height of the arch - on structural performance (i.e. stress, deflection and mass) is determined. Results indicate the sensitivity of the considered parameters and their importance in the design of scissor arches. With this knowledge in an early design stage, the subsequent design optimisation, detailed analysis and realisation are enhanced.