Development And Typical Application Of 2-DOF Stick-slip Piezoelectric Actuator

Piezoelectric actuator is a kind of precise driving device which has the merit of high precision,compact structure,rapid response,free of electromagnetic interference,and high compatibility.It has become an indispensable carrier in the high-tech field,such as aerospace,micro manipulate and micro assemble,micro/nano mechanical testing,optical engineering,biological cell engineering,micro robot,ultra-precision processing.For piezoelectric actuators,scholars have also done quantities of researches on the structural design and optimization,mathematical modeling,theoretical analysis,experimental analysis.These researches have greatly extended the application in the high-tech fields of piezo-driven technology,and thus facilitated the progress of these fields.This paper revealed that the present two degrees of freedom(2-DOF)piezoelectric actuators don’t have all the merits of large stroke,small size,and high precision based on the comprehensive acknowledgement of the research status of the piezoelectric actuators home and abroad.These limit the application and development as a precise positioning stage.Aiming at this problem,this paper revolves around a 2-DOF piezoelectric actuator with the merit of lager working stroke and small size.The presented 2-DOF piezoelectric actuator has a small dimension of 55 mm×55 mm×30 mm and a large working stroke of 19 mm×19mm.It adopted the series structure combining with the stick-slip principle to ensure the working stroke.The amplification ratio of the LFHM was calculated as 3.49 by the elastic beam method.At the meantime,finite element simulation of LFHM was implemented by Abaqus.The difference of the amplification ratio of two methods is only 1%,which verified the precision of elastic beam method.And the maximum stress of the LFHM is 44.47 MPa which is far less than the yield stress of AL7075,and the first resonant frequency is 968.89 Hz which make sure that the presented actuator has a wide working bandwidth.Then,a protype was fabricated and an experimental system was established to test the performance of the presented actuator.Experimental results show that the presented actuator has a stable movement,and its maximum speed moving along positive x axis,negative x axis,positive y axis,negative y axis is 5.2 mm/s,5.1 mm/s,4.98 mm/s,5.18 mm/s,and the resolution is 42 nm,47 nm,38 nm,50 nm,respectively.The motion speed can be adjusted easily by changing the driving voltage frequency and amplitude.And it has a stable output ability when the vertical load is under 2 N and the horizontal load is under 1 N.Facing at the practical demand of the process of micro structure array,the application research of the present actuator was developed based on the works mentioned above.An independent piezo-driven device,which has the features of low-cost,simple structure,and easy control strategy for fabricating micro-array structures on material surface,was designed.And the micro-array structures with different shape and depth were generated on different material surface,which verified the feasibility of the design scheme.In conclusion,this paper presented a 2-DOF piezoelectric actuator which has the features of compact structure,large working stroke,and high precision and stability.And the structural design,theoretical analysis,experimental research,and typical application were developed.These works will give a reference to the design and application of the 2-DOF piezoelectric actuator.