Basic Study on Controlling Piezoelectric Motion of Chiral Polymeric Fiber

In order to control the bending motion of poly-L-lactic acid (PLLA) fiber, which is one type of chiral polymer, caused by its shear piezoelectricity upon applying electric field, we simulated the electric field distribution in the PLLA fiber by a finite-element method. As a result, we found that the electric field distribution depends strongly on the distance between the electrodes on the surface of the PLLA fiber. On the basis of the simulation results, we design some electrodes on the surface of the PLLA fiber. When we applied an electric field with a tangential component in the cross section perpendicular to the fiber axis, using one electrode, linear motion could be realized owing to its piezoelectricity. Furthermore, when we added a radial component of the electric field using another electrode, the motion could be changed from linear to elliptical.