Abstract
This study applies multi-physics concurrent multiscale topology optimization to develop a lightweight porous linear actuation mechanism activated by laser energy. It meticulously explores thermal dissipation mechanisms, incorporating conduction, convection, and radiation dynamics. By examining various numerical cases, the study reveals a substantial 45% performance improvement in porous designs compared to solid actuators. The investigation extends to simultaneous optimization of multiscale porous displacement actuators, achieving a remarkable 75% weight reduction and demonstrating significant performance enhancements over single-scale designs. The increased freedom in micro-scale design allows more efficient material distribution, optimizing both macro and overall layouts. Sequential optimization of macro and micro-scale actuators is contrasted with concurrent multiscale optimization, showing inferior performance for separate optimizations. The study also delves into topology optimization under energy dissipation, focusing on multiple-rate thermal convection and revealing adaptive design behaviors in response to thermal stresses. Macro-scale designs influenced by convection exhibit perpendicular links and adaptive microstructures to enhance resilience and elasticity. The investigation also includes thermal radiation and convection, highlighting intricate design considerations for effective thermal dissipation. Ultimately, this study advances the understanding of multiscale effects in topology optimization, paving the way for more efficient and lightweight laser-activated porous actuators.