Effective component design synthesis using structural and shape optimization methods

Abstract

An efficient optimization-based component design synthesis methodology is developed to expedite the mechanical design of complex mechanical systems that contain several components. This method offers a modular design approach wherein the system design is obtained by representing all the components using lumped properties first and then synthesizing each component shape later to achieve those pre-optimized lumped properties. Methodology consists of four steps: (1) develop a lumped parameter analysis model of the component, (2) determine those lumped parameters such as stiffness and mass using structural optimization methods, (3) parameterize the component shape using pre-selected topology, and (4) optimize the component shape as a separate problem to achieve predetermined stiffness/mass characteristics. A new shape optimization software Optshape was developed using MSC/ Nastran's grid sensitivity capability to facilitate component shape optimization. Design of a spring joint for an automotive exhaust system is presented to demonstrate the effectiveness of the method and the Optshape software.