A Bioinspired Dual-Finger Micro Manipulator with Rubbing and Gripping Operations

In response to the growing demand for micromanipulation in ultra-precision fields, this work presents a novel 2-degree-of-freedom (DOF) dual-finger micro manipulator with large strokes and high resolution, inspired by the gripping and rubbing motions of human dual-finger. Interestingly, only a single bending piezoelectric actuator (BPEA) is used to drive the 2-DOF motion of the dual-finger manipulator, and a bolt-spring mechanism is incorporated to provide an adjustable gripping range with enhanced adaptability. Besides, structural optimization and simulations are conducted, and the performance is tested with a manufactured manipulator prototype. The micro manipulator achieves a gripping stroke of 216.8 µm with a displacement resolution of 66.3 nm, and a rubbing stroke of 552.6 µm with a resolution of 119.5 nm. It can rotate a 250 µm optical fiber by over 180°. The gripping range spans from 0 to 2108.4 µm. The proposed micro manipulator offers 2-DOF output with large strokes and nanometer-level resolution, showing great potential for advanced micromanipulation.