MEMS-based modular actuator for capsular endoscope applications

In this study, we propose and develop MEMS-based modular actuators for self-movable capsular endoscope applications. A structure of the micro actuator of 1 mm length and 350 μm width is optimized by using numerical analysis. The bottoms of the actuator legs are especially designed to achieve sufficient moving force of the actuator in smooth environment. The shape of the PDMS actuator is variously designed and it placed several positions to find the optimal position that provides a high transformation ratio. Five different types of design for the PDMS actuator are suggested and analyzed by numerical analysis. The fabricated micro actuator was heated by using a hot-plate and supplied with voltage by using a function generator. Displacement of the micro actuator was measured as a function of temperature from 27 to 300 °C. Each of V-groove shaped joints was actuated about 28 μm at 300 °C. Another design of the micro actuator had a maximum displacement of about 500 μm. The new concept was proven to be very useful for actuators that require a large displacement.