Feedback Control of an Achiral Robotic Microswimmer

作     者：U Kei Cheang Hoyeon Kim Dejan Milutinovic Jongeun Choi Min Jun Kim 

作者机构：Department of Mechanical Engineering and Mechanics Drexel University Philadelphia PA 19104 USA Department of Mechanical Engineering Southern Methodist University Dallas TX75275 USA Department of Computer Engineering University of California Santa Cruz Santa Cruz California 95064 USA School of Mechanical Engineering Yonsei University Seoul South Korea 

出 版 物：《Journal of Bionic Engineering》 (仿生工程学报（英文版）)

年 卷 期：2017年第14卷第2期

页      面：245-259页

核心收录：

学科分类：0710[理学-生物学] 0831[工学-生物医学工程（可授工学、理学、医学学位）] 081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术] 0802[工学-机械工程] 0835[工学-软件工程] 0836[工学-生物工程] 0702[理学-物理学] 080201[工学-机械制造及其自动化] 

基　　金：This work was funded by National Science Foundation (DMR 1306794)  Korea Institute of Science Technology (K-GRL program)  Army Research Office (W911NF- 11-1-0490)  and Ministry of Trade  Industry  and Energy (MOTIE) (NO. 10052980) awards to Min Jun Kim 

主　　题：microrobotics magnetic control low Reynold number chirality feedback control 

摘      要：Magnetic microswimmers are useful for navigating and performing tasks at small scales. To demonstrate effective control over such microswimmers, we implemented feedback control of the three-bead achiral microswimmers in both simulation and experiment. The achiral microswimmers with the ability to swim in bulk fluid are controlled wirelessly using magnetic fields generated from electromagnetic coils. The achirality of the microswimmers introduces unknown handedness resulting in uncertainty in swimming direction. We use a combination of rotating and static magnetic fields generated from an approximate Helmholtz coil system to overcome such uncertainty. There are also movement uncertainties due to environmental factors such as unsteady flow conditions. A kinematic model based feedback controller was created based on data fitting of experimental data. However, the controller was unable to yield satisfactory performance due to uncertainties from environmental factors; i.e., the time to reach target pose under adverse flow condition is too long. Following the implementation of an integral controller to control the microswimmers＇ swimming velocity, the mieroswimmers were able to reach the target in roughly half the time. Through simulation and experiments, we show that the feedback control law can move an achiral microswimmer from any initial conditions to a target pose.