Abstract
In this article, we describe an improved actuator for a cytology brush built into a capsule endoscope. The actuator is composed of a magnet with a rotating axis and a flexible material with a brush on the tip. The initial position housing the brush is latched by magnetic attractive force. When external DC magnetic field is applied, the latch is released due to magnetic torque and then the elastic force of the flexible material pushes out the brush. After that, the brush scrapes the surface of small intestine by AC magnetic field, and finally pulls back to the initial position by DC magnetic field. All these operations were checked within a cow's small intestine. In addition, we have proposed a novel stagnation function using rotating magnetic field for the capsule endoscope.