A bending and expanding motion actuator

A new bending and expanding motion actuator has been developed. The actuator is composed of 40 sheets of PZT unimorph cells. Each PZT unimorph cell´s electrode is divided into three sections. These cells are piled vis-a-vis. The vertically located electrodes are connected to one another with copper wire of 50 /spl mu/m in diameter. The actuator is 12 mm in diameter, 20 mm in length and 6.4 g in weight. The bending angle is 3 degrees with no weight and 9.5 degrees with 115 g weight in six directions (one or two electrodes are charged), and the expansion displacement is 700 /spl mu/m with no weight when three electrodes on a cell are simultaneously charged with the 150 V driving voltage. Multi-directional bending is realized by independent driving of each electrode on a cell.<>