Two-dimensional locomotion of a microrobot with a novel stationary electromagneticactuation system

Abstract

In this paper, we study the locomotion of a microrobot for intravascular therapy. Asan intravascular microrobot has to be small, a conventional actuator, such asa micro-motor, and a battery cannot be integrated. To solve this integrationproblem, we analyze a microrobot with an electromagnetic actuation (EMA) system.Previously, an EMA system using two stationary coil pairs was proposed for the2-dimensional (D) planar locomotion of a microrobot. The EMA system used twostationary pairs of Helmholtz coils and two stationary pairs of Maxwell coils in thex- andy-direction, respectively. This paper proposes a novel stationary EMA system using twopairs of Helmholtz coils and one pair of Maxwell coils. The 2D locomotion of themicrorobot using the proposed EMA system is analyzed and verified by variousexperiments. The microrobot actuated by the proposed EMA system was able to move inthe desired direction on the desired path. The comparison between the proposed EMAsystem and the previous EMA system showed that the proposed system had an 18%smaller volume and used 91% less coil current for the same actuation force than theprevious EMA system. The proposed EMA system produced 2D locomotion of themicrorobot, while having a small volume and a lower power consumption than the previousEMA system.