3D-Printed Adaptive Microgripper Driven by Thin-Film NiTi Actuators

Creating microscale actuated mechanisms in 3D space is extremely challenging due to limitations in microfabrication processes. In this work, we present a 3D-printed adaptive microgripper that is driven by thin-film NiTi microactuators with 3D-printed linkage mechanisms. The microgripper's fingers are passively adaptive so that the microgripper can provide conformal gripping on 3D objects. The microgripper can move its fingers by $\mathbf{225}\ \boldsymbol{\mu} \mathbf{m}$ and apply a blocking force of $\mathbf{30}\ \boldsymbol{\mu} \mathbf{N}$ per one finger when 20 mA was applied to the NiTi actuators. The microgripper was also integrated onto a printed circuit board with a current regulating circuit and a 9 V battery. Since the NiTi actuator requires a low voltage for actuation, the microgripper could be integrated with simple and affordable electronics. The fully integrated microgripper system was demonstrated playing with a shape sorting box at the microscale for the first time.