Design Optimization of a Shape Memory Alloy Actuated Morphing Aerostructure

Interest in shape memory alloys (SMAs) as lightweight actuators has motivated research into finding optimal morphing structure designs to replace conventional mechanisms in aerospace control systems. Prior to the development of robust constitutive modeling tools for these alloys, application design was based on trial-and-error studies conducted using an array of physical prototypes. Using this approach, a significant amount of time and materials were expended to produce each trial design. However, constitutive models now exist, implemented within a finite element analysis (FEA) framework, that can accurately and consistently predict the thermomechanical response of SMAs. This study considers the use of ModelCenter, a tool for automating simulation processes, coupled with the Abaqus FEA suite and a constitutive model to iteratively converge upon optimal designs in an automated fashion. The engineering design problem posed involves determining the configuration of a morphing aerostructure assembly with attached SMA flexures. Design inputs include material properties and component geometries. The objective is minimization of a cost function that quantifies the deviation of the computed actuation deflection from some target deflection. This paper presents a method for constructing this optimization problem, outlines the modeling tools used to execute each analysis, and highlights the results from the optimal design solution.