Dual Rotating Microsphere Using Robotic Feedforward Compensation Control of Cooperative Flexible Micropipettes

High flexible and high precise manipulation is one of the most critical technique for complex microsystem’s measurement, manufacture, and assembly. Although recent advances in microrobotics have successfully realized the automatic manipulation and positioning of tiny objects, their flexible manipulation in 3-D free space remains a challenge, such as the wide-angle rotation manipulation of microsize sphere, due to the complicate surface forces. Herein, this article proposed a feedforward model and realized the precise rotation for microsized sphere by two cooperative flexible micropipettes. Firstly, a microrobotic manipulation system with six degrees-of-freedom (DOFs) was developed and integrated with the microscope. Then, a feedforward compensation control strategy involving dual rotation was proposed for the precise manipulation of microsized sphere (
${\sim }90~\mu \text {m}$
) based on the analysis of contact forces. As a result, the rotation of the microsized sphere in two different planes was realized and the microsized sphere release procedure was also accomplished after rotation. Compared with existing techniques only allowing limited amplitudes rotation, this article realizes wide-angle rotation manipulation of microsized sphere in 3-D free space. This research opens new prospects for the microsized object accurate manipulation, which is expected to give a long-term impact for complex microsystem’s manufacture and assembly.
Note to Practitioners
—This article is motivated by the problem of the flexible manipulation of tiny object in 3-D space. The proposed nanorobotic manipulation system, two micropipettes and feedforward compensation model control strategy could realize the precise translational and rotational manipulation of microbeads in 3-D space, which offers obvious advantages of existing techniques. The proposed system and method could be a general solution for precise and flexible micromanipulation. Thus, it could find wide applications ranging from fundamental research to industrial applications, such as biological cell positioning, characterization of a particular micro/nanoregion, microassembly, and manufacturing.