A Two Degrees of Freedom Optically Controlled Levitating Microactuator

This article presents the design and analysis of a two degrees of freedom microactuator, optically controlled by a laser source. The actuator consists of an array of permanent magnets and a diamagnetic levitating pyrolytic graphite sheet (PGS) that achieves discrete, stable, and frictionless motion above the array without the need for feedback control. The actuation mechanism relies on the temperature dependent susceptibility of the PGS, where laser induced heating creates a localized imbalance in levitation forces, enabling controlled movement. The stable levitation positions were analytically determined using the zero-torque minimum potential energy method, and the system response to laser power was validated through both simulations and experiments. Results demonstrate that the actuator achieves reliable motion with submicron positioning accuracy, an average velocity of 7 mm/s, a 5% settling time of 1.80 s, and an energy efficiency of 2.86 mm/J. This work demonstrates the potential of optical, wireless control for precise, and noncontact actuation in microscale systems, with applications in micromanufacturing and automated microassembly.