Design of Heat-activated Compliant Mechanisms and Its Application to Product-Embedded Disassembly

Thermal transducers, which can be interpreted as thermally actuated compliant mechanisms, have found a wide range of applications, due to the reason of accessible source, easy controllability and reliability. During the past decade topology optimization techniques have been developed as efficient tools to design distributed type of complaint mechanisms. The generated results have been accepted and applied in practical applications. There has been research done to synthesize design of thermal actuation embedded electrical-thermal-compliant mechanisms, in which the non-uniform joule heating was generated through non-uniform electric current. In this research, time transient effect of heat transfer is proposed to produce the localized thermal actuation, while only simple forms of boundary heating is considered. Therefore non-uniform temperature distribution can be achieved by controlling the heating time before steady state is reached. This technique can be applied to design a novel type of integral attachment mechanisms to realized product-embedded disassembly. Design of heat-activated reversible snap-fit is posed as a topology optimization problem of compliant mechanism actuated with localized thermal expansion of materials through time transient heat transfer within the structure. Homogenization Design Method is utilized to calculate the effective material properties during the material distribution. Optimal configuration is presented, and in order to enhance manufacturability, simplification scheme and adjustment are applied to obtain realizable model. Final design is further verified with commercial FEA software. Ying Li, Kazuhiro Saitou, Noboru Kikuchi