Synthesis of Shape Morphing Compliant Mechanisms Using Load Path Representation

Abstract

Synthesis of shape morphing compliant mechanism is inherently different from typical single output problems, due to the multiple output points along the morphing boundary. Two synthesis approaches, using a fixed initial discretization mesh and using a load path representation, have been developed previously to simultaneously address the topology, size, and geometry aspects of a compliant mechanism. Due to insufficient diversity in later generations, pre-matured convergence to sub-optimal solution is observed in the load path approach. In this paper, additional genetic operation strategies are introduced to enhance the design diversity in each Genetic Algorithm population. The capabilities and limitations of the fixed mesh approach and the improved load path approach are studied through several examples. The results show that the load path approach can achieve better quality solution with less computation time than the fixed mesh approach. The load path representation can potentially lead to a fully systematic synthesis approach due to the absence of a prespecified initial discretization mesh. Boundary conditions are currently being incorporated into the design variable to understand their importance in structural topology.