基于柔性特征的胸鳍摆动推进模式研究

Several advantages make the propulsion mode by oscillating pectoral foils be a new research hot pot and an important sub-topic in the research area of bionic under-water robot, such as high efficiency, good maneuverability, excellent stability, low swimming noise and relative high swim velocity. Form and function of the bionic prototypes developed are far behind their nature sample. Performance of them can not fulfill requirements of practical application. The object of this project is to find an effective way to improve comprehensive properties of the bionic pectoral foil utilizing oscillating propulsion mode, based on its flexible features. Firstly, characteristics of the active flexibility and passive flexibility of the nature sample are absorbed; secondly, virtual prototype of oscillating foil with various active flexibility and passive flexibility distribution is built, and influences of the flexible characteristics on the propulsion performance are calculated; thirdly, the real bionic oscillating pectoral foil with controllable active flexibility and passive flexibility are designed and developed, and the virtual model constructed are verified through experiments; then, relationship between movement of the flexible oscillating pectoral foil and the ground effect will be studied; finally, the influence model of flexible features of the oscillating pectoral foil on its performance will be constructed and a new swimming mode with high efficiency based on the influence of ground effect will be built. This application has positive impact on design optimization of the bionic robotic fish driven by oscillating pectoral foils, also on the process of breaking through the bottlenecks hindering this kind of bionic robotic fish moving onto the practical application.

胸鳍摆动推进模式以高效率、高机动性、高稳定性、低噪声，并可以实现较高运动速度等优点，成为水下仿生机器人研究领域的新兴热点和重要分支。现有仿生原理样机在形态和功能上均远逊于仿生原型，尚未达到实际应用需求。本申请旨在从柔性角度出发，探求提升仿生胸鳍摆动推进模式综合性能的有效途径。首先，量化提取仿生原型的主动柔性和被动柔性特征；其次，构建不同主动/被动柔性特征的摆动胸鳍虚拟样机，计算柔性特征对推进性能的影响；而后，基于复合柔性机构建立可控主动/被动柔性的摆动胸鳍，实验验证分析模型；进一步，研究柔性胸鳍摆动运动与地面效应间的相互作用规律；最终，提炼柔性特征对摆动胸鳍性能的影响模型，并建立胸鳍摆动推进模式基于地面效应的高效能运动模式。本申请对胸鳍摆动推进模式仿生机器鱼的优化设计，突破性能瓶颈并迈向实用化有积极意义。

摆动胸鳍的主被动复合柔性特征对实现胸鳍摆动推进模式运动鱼类的高效率、高机动性、高稳定性、低噪声等优势十分重要。同时，受益于胸鳍摆动推进模式鱼类运动垂直于地面且在觅食等活动时贴近水底面游动的习性，其可利用地面效应有效提升游动速度和推进效率。本项目针对仿生胸鳍摆动推进模式，对自然界中仿生原型摆动胸鳍的运动规律进行深入分析，量化提取了仿生原型胸鳍鳍面运动变形参数，建立了仿生摆动胸鳍的运动学、简化动力学计算模型，得出了基于展向/弦向柔性特征的胸鳍运动学模型，计算与实验分析了主/被动柔性特征对摆动胸鳍推进性能的影响，仿真与实验分析了地面效应对胸鳍摆动模式推进性能的影响。在上述分析的基础上，研发了三台胸鳍摆动推进模式仿生机器鱼原理样机（驱动方式分别为基于两自由度空间并联驱动机构结合柔性变形的摆动胸鳍骨架，基于柔性软轴驱动的具备主动控制弦向变形能力的仿生胸鳍和改进型的二级曲柄滑块机构构成的驱动胸鳍骨架），构建了大型拖曳水动力测试平台，并对所研发的原理样机进行了系统的实验分析。在理论分析与实验研究的基础上，对胸鳍摆动推进模式仿生机器鱼应用于工程实际进行了初步探索。