Towards microrobotics: new liquid crystalline elastomer based photoactive microstructures

The thesis work concerns the development of microscopic structures able to perform robotic tasks entirely powered and controlled by light. The two main aspects addressed are the constituent material as well as the technique used for its microstructuring. The materials chosen for the fabrication are Liquid Crystalline Elastomers (LCEs), a type of shape-changing polymers that have attracted scientists and engineers for their ability to translate small molecular movement, triggered by an external stimulus, into large mechanical motion. Regarding the fabrication of microstructures, we chose the Direct Laser Writing (DLW), a technique based on a point-by-point polymerization induced by two photon absorption in the focus of a laser beam, where a tiny voxel is polymerized with high precision. Direct Laser Writing allows a rapid, cheap and flexible fabrication of microscale objects with nanoscale precision. The successful fabrication of LCE microstructures able to deform under light irradiation is demonstrated open to a new technology for the realization of complex microrobots.