Force through transpiration: biomimetic nanomechanical actuation
This work will develop a new class of bio-mimetic actuators which harness the energy in evaporating water to generate distributed forces across nano / microscale materials. Inspired by hygroscopic spore dispersal mechanisms in plants, the proposed mechanism would enable the infusion of common materials with distributed and programmable force generation. Specifically, we will: 1) design, fabricate and test a family of transpiration actuators with feature sizes ranging from 10-1000 nm, 2) develop a predictive model for the sub-micron scale interactions between water and elastomer, 3) employ the model to design and fabricate materials with embedded actuation which self-actuate and self-assemble into stable configurations by 'adding water'. As part of this last task, transient surface tension forces generated during evaporation will be used to shift the actuated materials between different stable shapes. Synthetic, distributed nano-actuation capable of scavenging energy from water to generate mN/mm2 force densities will also be demonstrated.
