压电柔顺x-y微夹持器的设计与分析

Design and analysis of a piezoelectric compliant x-y microgripper

针对微操作和微装配领域对微夹持器高位移放大比、多自由度和平动夹持的性能需求,采用双叶型桥式机构和平行四边形机构,设计了一种压电柔顺x-y微夹持器。利用有限元法建立了微夹持器的静力学与动力学模型,并通过ANSYS Workbench软件分析微夹持器的位移放大比、固有频率和输出耦合比。最后,搭建试验测试系统验证微夹持器的开环性能。试验结果表明:微夹持器x,y向的位移放大比分别为30.8和8.6,一阶固有频率为123.3 Hz;当施加10μm输入位移时,微夹持器x,y向的工作行程分别为0~616.6μm和0~51.0μm,夹持力范围为0~25.8 mN;微夹持器x,y向位移放大比与一阶固有频率的实验测试和仿真数值之间的相对误差分别为17.9%,19.8%,13.9%。试验结果验证了该理论模型和仿真分析的可行性。

Aiming at the performance requirements of high displacement amplification ratio,multiple degrees of freedom and translational clamping for microgrippers in the fields of micro-operation and micro-assembly,a double-leaf bridge mechanism and a parallelogram mechanism were used combinedly to design a piezoelectric compliant x-y microgripper.The statics and dynamics models of the microgripper were established by the finite-element method,and the displacement amplification ratio,the natural frequency,and the output coupling ratio of the microgripper were analyzed by the ANSYS Workbench software.Finally,an experimental test system was built to verify the open-loop performances of the microgripper.The experimental results show that the displacement amplification ratios of the microgripper in x-and y-directions are 30.8 and 8.6,and the first resonant frequency is 123.3 Hz.If an input displacement of 10μm is applied,the operating ranges in x-and y-directions are 0-616.6μm and 0-51.0μm,and the gripping force range is 0-25.8 mN.The relative errors of the x-and y-direction displacement amplification ratios and the first resonant frequency between experimental tests and simulation values are 17.9%,19.8%,and 13.9%,respectively.The experimental results verify the feasibility of the theoretical model and simulation analysis.