High-Precise Metallic Helical Microstructure Fabrication by Rotational Nanorobotic Manipulation System With Tilted Mandrel Compensation

Metallic helical microstructures are significant components applied in many fields, such as mechatronics, photonics, microelectromechanical systems, and biomedical engineering, but their fabrication with high precision remains a challenge. Herein, we report a general controllable approach for high-precise micro metallic helical structure fabrication by a self-developed rotational nanorobotic manipulation system. To reduce the fabrication error induced from the tilted mandrel, first, we propose an end-effector trajectory planning method to precompensate the tilted angle during rotation. Further, a hybrid vision and position feedback strategy is also developed to automate the fabrication process for obtaining a helical structure with uniform pitch distance consequently. The experimental results verify that our method is able to fabricate various micro helical structures with different dimensions with high precision up to 6 $\bm {\mu }$m (less than two pixel equivalent). The potential application of the helical structure as high-precise force sensor is also demonstrated for soft biomaterial (hemostatic sponges) characterization. This research paves an effective solution for the high-precise 3-D helical structure fabrication, which would prompt their applications in engineering and inspire other microstructure manufacturing as well.