Laser Controlled 65 Micrometer Long Microrobot Made of Ni-Ti Shape Memory Alloy

Microrobotics has many potential applications, such as environmental remediation, in the biomedical arena. However, existing microrobots exhibit practical limitations including inadequate biocompatibility and imprecise control. Here, a microrobot made of shape memory alloy (SMA) actuator which can be driven by laser scanning to perform microscale motions is introduced. The 65 mu m long microrobot having crawling-like motion can demonstrate the movement with 10.0 mu m s(-1) of the maximum speed. The microrobot is controlled by a laser affording wireless, spatiotemporally selective capabilities. During actuation, the robot exhibits crawling-like motions including trigger via the SMA as removal of adhesion to surface, propulsion induced by optothermal and optical trapping effects. Both theoretical predictions and experimental results confirm that the SMA microrobot can be actuated and controlled via laser scanning. The principle of SMA microrobots, and the optical actuation method, can be broadened to other applications that require deformable microscale structures suitable for mass production.