Reliability-Based Optimal Design of Thermal Actuated Compliant Valves
Year: 2012
Editor: Assoc. Prof. Poul Kyvsgaard Hansen, Professor John Rasmussen, Assoc. Prof. Kaj A. Jřrgensen, Assoc. Prof. Christian Tollestrup
Author: Kobayashi, Masakazu; Fukui, Yamato; Higashi, Masatake
Series: NordDESIGN
Institution: 1: Aalborg University, Denmark; 2: Design Society, United Kingdom
ISBN: 978-87-91831-51-5
Abstract
In recent years, compliant mechanisms have been paid to attention as new mechanisms to replace traditional rigid link mechanisms. Compliant mechanisms achieve a specified motion by deforming the structure elastically instead of relying on joint movements. Compared to traditional mechanisms, compliant mechanisms have several merits due to their monolithic structure without joints. Thus, the use of compliant mechanisms in mechanical products, medical instruments and MEMS can be expected to increase. For such promising compliant mechanisms, although many design methods have been developed, their reliability is not sufficiently considered. Since compliant mechanisms are quite different from traditional mechanisms, it is difficult to configure safety factor empirically. Thus, in this research, optimal safety factor, one of reliability-based design optimization (RBDO), is introduced into compliant mechanism design. In compliant mechanism design, there are two important criteria: output displacement and stress, but traditional OSF considers only single reliability. Thus, existing OSF is extended to allow for considering multiple reliabilities. In the case study, the proposed method is applied to a design of a thermal actuated compliant valve used for a micro water cooling system.
Keywords: Robust Design, Reliability-Based Optimization, Compliant Mechanism.