Magnetically-driven self-moving microactuators

This paper describes new micro-magnetic actuators for self-moving (-walking, -flying, and -swimming) microrobots. Their actuation force is generated by the interaction between external magnetic fields and the magnetic materials used for actuators. Accordingly, they can move independently without power supply cables. The walking actuator, composed of magnetostrictive thin films and two inclined legs, is capable of a high velocity of 65 mm/s and a reversible motion with forward and backward. The flying actuator has a pair of hard magnetic film wings with two elastic hinges and a soft magnetic wire body for attitude control. It can successfully fly without any cable or guide. Two kinds of swimming actuators, composed of a small magnet with an elastic fin or a spiral wire, can swim in viscous silicone oil with low Reynolds numbers.