Abstract
This paper presents the design, simulation, fabrication and testing of novel, untethered SU-8 polymer microrobots based on scratch drive actuators (SDAs). The design consists of two 100x120x10 mu m linked SDAs, individually operated close to their resonant frequencies. The resonant frequency and deflection behavior of an individual SDA can be controlled by its shape, thickness, and features. As a result, paired SDAs can be actuated individually or simultaneously by a multifrequency driving signal, allowing for two-dimensional displacement.
The fabrication process uses SU-8 as structural material and PMGI as sacrificial material. The SU-8 provides a flexible material for the SDA's plates as well as the bushing. Finally, a Cr/Au layer is blanket deposited to provide electrical conductivity.