电机-智能材料复合型仿生鳍设计及分析

针对目前开发的仿生鱼鳍驱动方式及其功能单一等不足,提出一种电机-智能材料复合型仿生鳍。首先介绍仿生鳍机构原理及设计思路,对仿生鳍单元的运动关系进行建模;结合动力学仿真软件分析不同曲柄长度时鳍条运动角位移、角速度和角加速度随时间的变化情况;最后试验测试仿生鳍推进器的平均推进速度和平均推进力随鳍条运动频率的变化情况,并比较分析相同运动学参数下鳍条摆幅从根部至端部逐渐增大运动模式和鳍条摆幅从根部至端部等幅运动模式推进性能的差异。该研究充分利用机电系统响应速度快和驱动力大的优势,结合智能材料形状记忆合金功重比高和柔性驱动等优点,使仿生鳍不仅实现了两种驱动方式上的融合,而且通过仿生鳍的多种运动方式(波动、摆动以及复杂三维柔性运动),满足了巡游、转弯以及稳定性调节等多种需求。

Design and Analysis of a Motor-Intelligent Material Compounded Biomimetic Fin

According to the shortage such as single drive mode and function of the current development of biomimetic fin, we propose a motor-intelligent material compounded biomimetic fin. First, the principle of the structure especially the design solution was introduced. Then, the kinematic of biomimetic fin unit was established. In combination with dynamic simulation software, the change of the angular displacement, angular velocity and angle acceleration of fin ray was presented under the different cam speed and different crank length. Finally, the variety of averaged propulsion velocity and averaged thrust with frequency was experimentally tested. The propulsion performance between the two modes that the amplitude is fairly constant from roots to ends and the amplitude gradually increased from roots to ends with the same kinematic parameters was compared. The study takes the advantages of mechanical and electrical system such as high response speed and big driving force, as well as the high power to weight ratio and flexible drive of intelligent material SMA, which not only realizes the integration on the two different kinds of drive modes, but also satisfy the requirements of cruising, turning, stability control through undulating, oscillating and complex three dimensional flexible movement of biomimetic fin.