Swimming Properties of a Bending-Type Magnetic Micro-machine.

Basic swimming properties of a bending-type in-pipe micro-machine were investigated. The micro-machine consists of a permanent magnet attached to an elastic plate, and can be remotely driven by an external alternating magnetic field. The swimming velocity depends on the excitation conditions and the shape of the elastic plate. First, we examined the frequency dependence of the swimming velocity and found that two peaks occurred due to the mechanical resonance and a lack of the power required for swimming. Next, we examined the effect of the shape of the elastic plate, and found that the shape suitable for higher velocity changed markedly according to the intensity of the magnetic field.