Synthesis of Superelastic Compliant Mechanisms for Target Shape Matching

Abstract

The design freedom of the additive manufacturing (AM) process has created new avenues for compliant mechanisms to have more complex geometries, functionality, and mechanical behavior than conventional manufacturing methods offer. However, the challenge in the assumption of 'free complexity' in AM is the trial-and-error often involved in creating a design that behaves as intended. To address this problem, a synthesis method incorporating nonlinear-elastic materials and large deformations as geometric nonlinearity is proposed, using an assembly of building blocks to construct a compliant mechanism. Designs generated by the model illustrate the optimization of the building block selection, size, shape, and topology to achieve different deflected states. The combination of the superelastic behavior of shape memory alloys such as Nitinol, and the exploration of different building block geometries, has been shown to enhance the flexibility of the optimized mechanism to reach such target shapes.