Study On Electrostatic Actuator Based On Triboelectric Nanogenerator

As we all know,triboelectrification is the result of electron transfer from one object to another,which causes two objects to carry the same amount of charge at the same time.For people in life,its existence usually is a kind of negative effect,especially in winter.However,the team of professor Zhong Lin Wang of Georgia Institute of Technology in the United states invented Triboelectric nanogenerator(TENG)to fully utilize this kind of effect.TENG can convert mechanical energy in the environment into electrical energy,which based on the principle of triboelectrification and charge induction,such as waves,sounds,muscle contractions,mechanical vibrations,etc.The charge separation between the two layers of polymer films will lead to the formation of potential difference.In addition,not only the fabrication process of TENG is simple and low cost,it also can be used in large-scale production.At the same time,it has excellent durability and plasticity,so TENG can be easily combined with other devices.Therefore,TENG and its applications are an important research direction of nanoenergy.Here we have designed TENG for different applications.The main research points in this dissertation are as follows:(?)Integrate a TENG with electrostatic actuation system(EAS)to manipulate the movement of micro-droplets and fine solids.The mechanical triggering of the TENG produces a very high electrostatic field inside the electrostatic actuator,producing a Coulomb force that drives tiny objects(liquid or solid)in the electrostatic actuator.Therefore,the tribomotion of TENG can be used as a driving source and control signals of electrostatic actuators.A TENG device with a 70 cm~2contact surface can drive water droplets to move within a 2 cm gap.At the same time,this self-powered electrostatic actuator can also control the convergence of two droplets which have the same charge polarity and different composition.In addition,based on the same principle of operation,the electrostatic actuator also verifies its ability to manipulate solid objects(such as a tiny steel ball).By sliding along the segmented ring electrode,the fine solid can follow the Kapton film for rotational motion very well.The concept of this self-powered electrostatic actuator has excellent applicability for a variety of micro/small actuation devices,electromechanical systems,human-computer interaction and more.(?)Based on dielectric elastomer actuator(DEA),tunable optical gratings(TOGs)and TENG combined so that the grating period can be controlled by dielectric elastomer actuator.Therefore,a self-powered TOGs system can be implemented,with TENG as the power and control module for its system.In combination with unique output performance of the TENG,three different TOGs systems were designed and used to compress or expand the spacing of the grating array by driving the dielectric elastomer actuator.The contact surface of 120 cm~2 of TENG,the separation of movement can reduce the grating period 16.5%or increase 9.4%.Both one-dimensional and two-dimensional grating matrices are designed into the TOGs system so that TENG can control both grating systems for multi-function modulations.At the same time,the system can realize fast,efficient and multi-function grating period modulation,and the main problem is that the maximum transfer charge of TENG device will be greatly suppressed under a limited value.Therefore,self-powered TOGs have been proved to have great application prospects,such as various display systems,optical fiber sensors,optical fiber communications and the like.(?)Researchers have made every effort to pursue the light weight and high flexibility of wearable electronic products,and require the related energy harvesting devices to have ultra-thin thickness and high scalability.Therefore,we experimentally proposed a flexible TENG,which can be used as the second skin of human body.The TENG has a total thickness of about 102?m and can work permanently with 100%strain.Carbon grease coated on the elastic film surface as a stretchable electrode,in order to achieve the fine geometry of the electrode control.This flexible TENG can even work on human fingers without interfering with body movements.The open-circuit voltages and short-circuit currents of devices with a contact area of 9 cm~2 can reach 115 V and 3?A,respectively.In this paper,two self-powered sensor systems with optimized identification strategy are designed,which verify the application prospect of this flexible TENG.The superior properties of ultra-thin thickness,high stretchability and fine control make it more potential applications in wearable self-sensing systems,electronic skin,artificial muscles and soft robotics.