Investigation into Effect of Magnetic Moments to Swimming Behavior and Performance of the Soft Milli-Film Robots

Xiuzhen Tang#

Laliphat Manamanchaiyaporn#,Email

Center of Excellence in Creative Engineering Design and Development, Research Unit in Multi-Scale Robotics, Thammasat School of Engineering, Faculty of Engineering, Thammasat University, 12120, Thailand

Abstract

For years, soft swimming milli-robots have been developed by various techniques to fulfil medical therapy and treatment. Real-time remote controllability, small size, soft interface, and non-toxicity are critical requirements for them to cope with blind, unstructured, and fluidic conditions inside life. Theoretically, the magnetic response of the robot to actuation relies on magnetic moments that behave as a vector, and they consist of orientation and strength. In soft swimming robotics, they are employed as a motor-less mechanism for the swimming through a deformable structure with high degrees of freedom provided by compliance with minimal control of a magnetic field. Here, this work investigates how both aspects impact the swimming behavior and performance of the soft-structured milli-robots. Elastomer and NdFeB-microparticles are utilized to fabricate three robots with distinguishing aspects of magnetic moments (uniform/non-uniform orientation coupled with uniform/non-uniform strength). Under the same control parameters and testing conditions, the experimental results interestingly report that each aspect provides a mechanism and benefit of swimming performance for the robots differently. Non-uniform orientation mainly influences the pattern of body transformation, but non-uniform strength relates to how fast the body transforms. The robot with the aspect of both non-uniform orientation and strength is the best swimmer. If the scale of the robot is down in micrometers, non-uniform strength is highly recommended to define the swimming mechanism. These findings are useful for designing an individual robot to operate in life by choosing a proper aspect to fit medical tasks significantly.

Investigation into Effect of Magnetic Moments to Swimming Behavior and Performance of the Soft Milli-Film Robots