形状记忆合金丝驱动的仿生鲫鱼设计与研究

发布时间：2019-02-26 14:49

【摘要】：仿生机器鱼与传统螺旋桨推进的水下机器人相比,具有更高的游动效率以及更好机动性和稳定性。而目前仿生机器鱼广泛采用电机驱动,普遍存在噪音大、效率低、动作生硬以及柔性不高等缺点。随着智能材料科学的发展,采用与动物肌肉性能相似、具有传感功能的智能材料制成机器鱼的驱动结构,具有结构简易、柔性好、噪声低以及易于主动产生复杂运动等优点,因此逐步成为仿生机器鱼驱动器未来的发展趋势。首先,以鲫鱼为仿生对象,在对其形态结构以及游动机理进行研究的基础上,提出了研制一种形状记忆合金(Shape memory alloy,SMA)丝驱动仿生鲫鱼的设想。根据鲫鱼样本的肌肉驱动特征设计仿生鲫鱼的驱动结构,并在此基础上完成了柔性仿生鱼尾的设计。同时设计了仿生鲫鱼的刚性前身与控制系统。再者,对仿生鲫鱼尾部的摆动性能进行了分析,通过对柔性仿生鱼尾的摆动过程进行了力学分析获取了SMA丝的应力、应变与鱼尾的弯曲角度的关系方程。引入SMA丝电流加热的热力学方程以及描述SMA丝相变的本构模型方程,结合力学分析的结果,可获得鱼尾最大弯曲角度关于加热时间、加热电压和初始温度的函数关系方程,以用于其摆动性能分析。最后,完成柔性尾鳍的制作并搭建了试验平台用于测试柔性尾鳍的摆动性能,通过摆角试验、对称性试验、摆动和回摆试验、加热模式试验以及推进力试验,试验结果显示柔性仿生鱼尾在摆动角度为16°左右时,可达到最高1.4Hz的摆动频率。而在摆动角度为21°和最高摆动频率0.8Hz的条件下可获得最大的平均推进力0.041N。而仿生样机的游动试验中,通过不同摆动频率下游动性能的试验数据对比。在摆动角度25°,摆动频率0.3Hz下仿生样机具有较好的综合游动性能并实现了最高游动速度0.28BL/s。
[Abstract]:Compared with the traditional propeller-propelled underwater robot, the bionic robotic fish has higher swimming efficiency, better maneuverability and stability. At present, the biomimetic robot fish is widely driven by motor, which has many disadvantages, such as high noise, low efficiency, rigid motion and low flexibility and so on. With the development of intelligent material science, intelligent material, which is similar to animal muscle and has sensing function, is used to make the driving structure of robot fish. It has the advantages of simple structure, good flexibility, low noise, and easy to produce complex motion on its own initiative, and so on. Therefore, it has gradually become the future development trend of bionic robot fish driver. Firstly, taking crucian carp as biomimetic object, on the basis of studying its morphological structure and swimming mechanism, the idea of developing a shape memory alloy (Shape memory alloy,SMA) wire driven crucian carp is put forward. According to the muscle driving characteristics of crucian carp samples, the driving structure of biomimetic crucian carp is designed, and the flexible bionic fish tail is designed on this basis. At the same time, the rigid predecessor and control system of biomimetic crucian carp are designed. Furthermore, the swinging performance of the tail of the biomimetic crucian carp is analyzed. The relationship equation between the stress, strain and the bending angle of the fish tail is obtained through the mechanical analysis of the swinging process of the flexible biomimetic fish tail. The thermodynamic equation of the current heating of SMA wire and the constitutive model of describing the phase transition of SMA wire are introduced. Combined with the results of mechanical analysis, the functional equation of the maximum bending angle of the fish tail with respect to the heating time, heating voltage and initial temperature can be obtained. In order to analyze its swing performance. Finally, the flexible tail fin is made and the test platform is built to test the swing performance of the flexible tail fin. The swing angle test, symmetry test, swing and back swing test, heating model test and propulsion force test are used to test the swing performance of the flexible tail fin. The experimental results show that when the swing angle of the flexible bionic fish tail is about 16 掳, the maximum swing frequency of 1.4Hz can be achieved. When the swing angle is 21 掳and the maximum swing frequency is 0.8Hz, the maximum average propulsion force is 0.041 N. In the swimming test of the bionic prototype, the experimental data of the downstream dynamic performance of the bionic prototype are compared with each other at different swing frequencies. At the swing angle of 25 掳and the swing frequency of 0.3Hz, the bionic prototype has better comprehensive swimming performance and achieves the highest swimming speed of 0.28BL.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TP242

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