压电双轴驱动柔顺微夹钳设计与控制

Design and control of flexible microgripper with piezoelectric biaxial-driven

提出了一种压电双轴驱动对称结构的柔顺微夹钳。该微夹钳由2个对称分布的桥式放大器组成,每个桥式放大器分别连接到一个杠杆机构来放大输出位移。利用虚功原理和拉格朗日方程建立运动学和动力学模型。考虑到各参数对机械结构的影响,分析机构的静力学和动力学特性,同时采用有限元方法对建立的模型进行评估和验证。为了进一步揭示所设计的微夹钳的性能,利用线切割方法加工出了微夹钳样机。采用动态面控制算法对系统进行了一系列控制实验来说明微夹持器的运动特性。结果表明:微夹持器的左、右放大器的放大倍率分别为11.25和11.67,其位移跟踪性能好,通过夹持纸片,检测了末端微夹持力的大小,验证了前面设计分析的正确性和可行性。

A piezoelectric biaxial-driven flexible microgripper with symmetrical structure is proposed,which consists of two symmetrically distributed bridge-type amplifiers,each bridge amplifier is connected to a lever mechanism to amplify output displacement.The kinematic and dynamic models are established by using virtual work principle and Lagrange equation.Considering the influence of each parameter on the mechanical structure,the static and dynamic characteristics of the mechanism are also analyzed.The established models are evaluated and verified by finite element method.In order to further reveal the performance of the designed micro-gripper,a prototype of the micro-gripper is fabricated by linear cutting method.A series of control experiments are carried out to illustrate the motion characteristics of the micro-gripper by adopting the dynamic surface control algorithm on the system.The results show that the amplification ratios of the left and right amplifiers of the micro-gripper are 11.25 and 11.67,respectively,and its displacement tracking performance is good.By clamping the paper,the magnitude of end micro-gripper force is detected,which also verifies the correctness and feasibility of the previous design and analysis.