Concept of a micro finger using electro-conjugate fluid and fabrication of a large model prototype

Electro-conjugate fluid (ECF) is a kind of functional fluid, which produces jet flow (ECF jet) when subjected to high DC voltage. It is ascertained that a strong ECF jet is generated under nonuniform electric field, for example, around a pair of a needle-electrode and a ring-electrode (a needle-ring electrode pair). This study proposes and develops a novel micro finger with two-DOF motion using ECF jet. First, we propose a concept of novel micro finger driven by ECF jet (ECF micro finger). The ECF micro finger consists of a finger tube with three chambers along its axis and an ECF jet generator with three needle-electrodes and a plate-electrode with three holes. When the ECF jet generated at the ECF jet generator is applied to the chambers of the finger tube, the pressurized chambers expand and the other chambers shrink resulting in the finger tube bending. Next, a large model of the proposed ECF micro finger, with finger tube diameter of 4.5 mm, is fabricated in order to confirm our concept. Finally, we investigate the static characteristics of the large model by experiments.