软体机器人的驱动一般由较硬的驱动元件与柔性介质复合而成，两相材料耦合大变形的精确描述是驱动部件结构设计与运动控制的关键.针对复合柔性板结构大变形的特点，基于绝对节点坐标方法，通过变形协调条件将梁和板单元进行耦合，同时引入压电驱动材料本构方程，建立带压电材料驱动器的复合柔性板结构动力学模型，并对其动力学特性进行分析，以研究不同参数对该动力学模型的影响.结果表明：柔性悬臂板结构在压电驱动作用下产生弯曲变形，变形量及板末端位移随驱动电压的增大呈近似线性增大规律，且板结构弹性模量越小则该变形量增大的程度越大；随着弹性模量减小，板结构产生的周期性振动幅度增大，周期变长.
Coupled flexible structures are widely applied on soft robots as actuators, which are combined with hard electric actuating material and flexible medium. The accurate description for the rigid-flexible coupling and large deformation is of great importance for the structure design and accurate control of the actuators and soft robots. In this paper, a flexible beam-plate coupled structure is established based on the deformation compatibility condition, the deformation of the structure is described with absolute nodal coordinate formulation, and the dynamic equations are developed based on Hamilton’s principle. To investigate the influence of actuation, piezoelectric material constitutive equations are imposed to the beam element as a piezoelectric actuator of the structure. The results indicate that the deformations of the coupled flexible structure under piezoelectric actuation increase linearly with the increase of input voltage. The structure conducts periodical vibrations under actuation, the amplitude and the period of the vibration increase nonlinearly with the decrease of Young’s modulus.
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