As demands of microrobots increases, micro-actuators for lhe microrobots are actively studied. However, miniaturized motors cannot be easily applied 10 microrobots owing to lhe limitatioJ1s of lheir sizes antd generating forces. Therefore, a new smart material for microrobots should be developed. A mong various smart materials, such as PZT, SMA, Ferrofluid, we focused on a ferropaper actuator using ferrof1uid. The ferropaper actuator is regarded as a smart mater ial and can show large displacemenls, excellent repetilion perfonnances, and relative small actuation forces. In lhis paper, a cellulose is used 10 make a backbone membrane because il has superior properties compared with any others conventional papers. The cellulose paper backbone membrane is easily fabricated as complex shapes and shows a large displacement in a magnetic tield. In detail, patterned ferropaper actuator is made of cellulose acetate using general MEMs procedure and PDMS molding method. Finally, through EDS mapping and alignment experiments of the làbricated ferropaper actuator using an electromagnetic actuation (EMA) system, the patterned ferropaper actuator was characterized.

자성유체 유체씰에 사용할 수 있는 마그네타이트를 공침법에 의하여 합성하였다. 마그네타이트의 평균입자크기는 동적광산란 측정장치(DLS)에 의해 약 10-12 nm 로 측정되었다. XRD 측정결과, NH4OH 의 농도가 증가함에 따라 마그네타이트의 결정화도가 증가하였다. 수중 분산된 자성유체의 제타전위는 -49.3 mV 에서 -26.2 mV 까지 DLS에 의하여 측정되었다. 입자의 형상은 구형이었고, 수상과 유상 자성유체에서 스파이킹 효과를 확인하였다.

Magnetite powder for kerosene-based ferrofluid was synthesized by air oxidation of waste acid containing Fe2+ and Fe3+ ions in the pH=11 at 60℃. Stable kerosen-based ferrofluid was prepared by addition of polyoxyethylene nonylphenyl ether(POENPE) to the magnetite containing water. Dispersion mechanism of an addition POENPE to the magnetite was examined by means of the fraction of solid dispersed FT-IR spectrum. And magnetic properties of kerosen-based ferrofluid were examined by method of Vibrating Sample Magnetometer. In order to remove oil on the water surface by an addition of kerosen-based ferrofluid, the optimum conditions were examined.