Topology optimization of compliant mechanisms with multiple outputs

Multiobjective Optimization for the Aero-Structural Design of Adaptive Compliant Wing Devices

The design of morphing structures must combine conflicting structural requirements and multiple load conditions that are related to the aerodynamic shapes aimed at optimizing aircraft performance. This article proposes a multilevel approach for the design of adaptive compliant wing devices. A set of aerodynamic shapes, and associated their loads, is defined by a shape optimization, coupled with a three-dimensional parametric technique, that can identify only feasible shape changes due to the morphing. A topology and sizing multiobjective optimization drives the Pareto-optimal structural design of the compliant structure, which is able to deform itself to match, once actuated, all of the previously defined aerodynamic shapes. Next two design levels produce a more detailed solution which is extended until the definition of the complete device. A 90 pax, twin prop green regional aircraft is used as an innovative aircraft demonstration platform for the design of the morphing droop nose to be installed on the wing. The results show the structural capabilities of this device in terms of the external shape quality and the strain requirements. This work enables the validation of the design method and prove the functionality of compliant structures when accounting for the aeroelastic effects due to the interaction with the wing-box.

Design and Analysis of Compliant Rotary Joint

Unlike rigid-body mechanisms, compliant mechanisms (CMs) gain some or all of their motion from relative flexibility of their joints. This paper presents a pseudo-rigid-body model (PRBM) method and virtual work to design and analyze kinematics and dynamics for compliant rotary joints or flexure hinges in the processing of compliant mechanisms. The stress at flexible pivot, the nonlinear-large deflection of flexure hinge, the relationship between displacement and force and/or torque, stress were taken into account in this work based on PRBM. A numerical software package, ANSYS, was exploited to illustrate schematic diagram of the stress versus to horizontal displacement of free end AB of flexure hinge. A mechanism with the desired structure is that one of the most popular aspects, which is needed to take into account in the design phase in advance. The results revealed that the proposed effective approach can be further easily applied in compliant mechanism structures. Future work will focus on multi-objective structural optimization of the flexure hinge.