Manipulation of micro-particles using a magnetically actuated microrobot

Recently, various micromanipulation methods using a microrobot have been studied in medicine and biology. In particular, the methods based on the use of a microrobot actuated by an electromagnetic actuation (EMA) system have received much attention because the microrobot using EMA system has free locomotion and precise controllability. These advantages of an electromagnetic actuated microrobot can be used to manipulate micro-particles. Previously, we proposed a 2-dimensional (2D) locomotive microrobot using EMA system and realized the free 2D locomotion of a microrobot of 10 mm length and 1 mm diameter. In this paper, we propose a microrobot for the manipulation of micro-particles. First, we fabricate a microrobot of desired shape and size by the conventional micro-molding technique. Second, we control the fabricated microrobot by using a 2D EMA system and test its basic performances such as directional controllability and velocity. The results of these basic tests confirmed that the microrobot had precise directionality with direction error from 1.52 deg. to 2.16 deg. and moving velocity range from 2.34 mm/s to 18.67 mm/s. In addition, the microrobot has the positioning errors in the 0.07-0.12 mm range and the propulsion force of the microrobot is continuously changed in proportional to the applied current in Maxwell coil. Finally, the proposed microrobot and its EMA system were tested for their ability to position a micro-particle. The results confirmed that the microrobot using the EMA could be used for the manipulation of various micro-particles.