Simulation and Analysis of a Novel Micro/Nano Piezoelectric Actuator

Novel ideas in micro and nano technologies specially in micro/nano piezoelectric actuators that are extensively used in medical, automotive, robotics and other fields have improved the sensivity and accuracy of the instruments that work using these actuators [1]. The applications include chemical sensors, acceleration transducer, pressure transducer, micro and nano grippers and so on. Micro and nano grippers are important devices to be used as a micro/nano knife in bio research or assembly of components for micro machines. In this paper, a novel method to increase the displacement of the tip of cantilever piezoelectric as our model will be introduced. Applying this method, micro/nano sensors and actuators will have more sensivity and accuracy than traditional methods-based ones.The technology commonly used in MEMS/NEMS gripper can be described as four main fields which are thermal, Shape Memory Alloys (SMA), electrostatic and piezoelectric actuator. In general, most actuators execute well in some fields but poor in others. For example, electro-thermal actuators are known for their excellent large deflection and force. But traditionally the temperature of the structure is high and in bio research like in surgery operations, using of this method is very difficult and in some cases is impractical. Also, typical Shape Memory Alloys including combination of metal elements such as Ti Ni have advantages like high power density, but they are mainly affected by and greatly depend on the surrounding temperature conditions. So, both of electro-thermal actuator and SMA require cooling system to reverse their action. On the other hand, the advantages of electrostatic actuator are small actuation energy and high frequency response, and disadvantages are high driving voltage, large working area and low output force [2]. Piezoelectric actuators have excellent operating bandwidth and large forces, high power density, and well reversion, but the displacements generated are so small that the piezoelectric research focuses on developing an architecture that can generate high displacement. Hence in this work we make attempt to increase this displacement.