During the project, we embarked on a multifaceted exploration centered on microscale encapsulated bubbles and their potential applications for acoustically actuated microrobots. We had four objectives that we were able to achieve, as detailed hereafter.
Understanding Fluid-Structure Interaction on the Microscale
Our initial goal was ambitious: predict the thrust generated by encapsulated microbubbles. We combined three approaches: developing an analytical model, validating it through experiments and numerical simulations, and finally disseminating our findings. These efforts resulted in publications in leading journals and conference presentations. We also shared a MATLAB code to benefit the wider community.
Crafting Multi-Material Microscale Machines
Creating complex microscale machines requires bondable materials with unique properties. We explored different materials, and various printing parameters, and evaluated the different material compatibility, culminating in a refined fabrication protocol. We presented our progress at international conferences and have publications under review, highlighting our contribution to this field.
Predictive Design for acoustically actuated Micro-Robots
Initially, we aimed to induce shape modification through structural instabilities such as buckling. However, challenges led us to pivot towards exploring different nonlinear acoustic forces, like secondary acoustic radiation forces. These act between oscillating microbubbles, and can be controlled through bubble geometry and excitation signals. Collaborative experiments and extensive modeling led us to develop a predictive tool for specific micro-machine designs, a significant leap in our understanding of these systems.
Autonomous Response via Acoustic Forces
Though our initial goal of inducing buckling wasn't realized, our exploration of nonlinear acoustic forces bore fruit. We designed controlled, acoustically actuated micro-machines, each carefully characterized and modeled. These machines can serve as building blocks comprising complex acoustically actuated and 3D-nanoprinted robots. Our work culminated in presentations at international conferences and a journal paper, marking a notable achievement in this domain.
This project encompassed diverse explorations and adaptations, ultimately advancing our understanding of micro-machines influenced by acoustic forces, showcased through our publications and presentations. The project’s outcomes have reached far and wide, connecting with both academic and industry circles while engaging the broader public.
Dissemination to Academic and Industry audiences
The core findings from our research found their way to academic communities via esteemed peer-reviewed journals and key international conferences. Beyond academia, we interacted with industry experts during four pivotal events: two CMi days in 2022 and 2023 in Lausanne, and two Swiss Robotics Days in 2022 and 2023 in Lausanne and Zurich.
Outreach to Diverse Audiences
Sharing our project wasn’t confined to academic circles. We leveraged social media platforms and the MICROBS laboratory website to disseminate project products. Additionally, we opened our doors to the general public through key events. At the Swiss Robotics Day in 2022 in Lausanne, we set up a booth and interacted with visitors. Similarly, during the EPFL open-door event in 2023, we showcased our research to the public across two informative days. We also hosted visits from high school students from Lausanne, broadening our reach to inspire the next generation of scientists and engineers.
