基于仿生鱼侧线与石墨烯传感的潜航器流场环境可测性机制与感知系统研究

In order to guarantee the safe operation and successful mission of underwater vehicles, the accurate flow sensing is necessary. As AUV operation environment becomes increasingly complex and the acoustic stealth performance of the detected object also improves quickly, the effect of traditional acoustic sensing technology is significantly affected. Inspired by the sensing basis of fish lateral line organ, the artificial lateral line sensing technology is highlighted as an effective way to achieve highly precise flow field sensing. But the latest performance of artificial lateral line is still not comparable to real fish when they are in the similar dimension. The root problem results from the ambiguous testability mechanism of lateral line system. Most research focus on fish macro structure and few people pay close attention to the sensing sensitivity, the layout and density of the sensing array and so on. This project aims to solve such a problem. First the relationship between the lateral line feature and sensing ability and how they work well will be thoroughly analyzed. Then, then testability mechanism of AUV flow filed will be explored. Characteristics, like required sensing element sensitivity, sensing array layout, layout density, will be determined so as to achieve an equivalent perception ability compared to fish. Supported by the testability mechanism, a highly sensitive and miniature sensor unit based on the nano material graphene and Atomic Point Contact electron tunnel effect will be designed. A sensing array information fusion algorithm based on space layout optimization will be proposed. Finally, a flow filed sensing system will be developed.

流场环境准确感知是潜航器安全运行、任务成功的必要条件。随着潜航器服役环境越来越复杂和目标声隐身性能的提高，传统声感知技术的效果受到较大影响。受鱼侧线感知原理的启发，基于仿生鱼侧线的流场环境感知技术被认为是解决该问题的一种有效途径。目前该方面的研究结果难以达到相应比例下鱼感知能力。究其根本原因，一个主要方面是目前的研究多为鱼侧线宏观形态的仿生，对准确感知流场环境所需的传感灵敏度、传感阵列分布形态、分布密度等可测性机制不够清晰，形似而神难似。本项目针对该问题，首先深入分析鱼侧线特性与感知能力的关联关系与作用机制；然后探索建立潜航器流场环境的可测性机制，提出实现潜航器尺寸下近鱼类感知能力所需的传感单元灵敏度、传感阵列布局形态、布局密度等特性；在此机制下，基于石墨烯纳米材料和原子点接触隧穿原理设计高灵敏度微型化传感单元，研究基于空间布局优化的传感阵列信息融合感知算法，设计一种新的流场环境感知系统。

流场环境准确感知是潜航器安全运行、任务成功的必要条件。本项目针对该技术需求，受鱼侧线感知原理的启发，开展了基于仿生鱼侧线的流场环境感知相关技术研究。项目主要研究内容与重要结果有：（1）分析了鱼侧线特性与流场感知能力的作用机制与关联关系。通过建立鱼侧线感知单元与结构的生物力学模型，分析了鱼侧线感知流场的时域敏感特性和频域敏感特性，建立了鱼侧线敏感特性与流场感知能力的关联关系。分析表明，鱼侧线的流场感知能力来源于其对局部流场水流速度和压力梯度信息的感知，感知的频率范围为几Hz至几十Hz。（2）探索建立了潜航器流场环境的可测性机制。从理论上给出了仿生鱼侧线流场感知可能达到的最远距离，即λ/2π（λ为水下声波波长），构建并分析了偶极子压力分布模型，建立了感知距离与阵列压力传感器差压灵敏度的关系。（3）基于石墨烯纳米材料设计了高灵敏度微型化压力传感单元。通过理论建模、有限元建模仿真和分子动力学建模仿真，研究了不同形状下Graphene薄膜的压阻效应，建立了薄膜尺寸、面积与传感器灵敏度关系的理论模型，设计了石墨烯薄膜压力传感器的结构、工艺流程和加工方案，制作得到了符合要求的石墨烯压力传感器单元。（4）提出了基于空间布局优化的传感阵列信息融合感知算法，集成设计了一种新的流场环境感知系统。提出了基于空间谱估计的传感阵列信息融合感知算法，设计了仿生鱼侧线传感阵列，集成传感阵列、信号采集与感知算法，设计实现了一种流场环境感知系统。该系统采集传感阵列感知的压力信息，利用基于空间谱估计的偶极子源定位方法，实现了不同阵列长度和密度下的偶极子源定位能力。结果表明，有效定位距离约为一倍阵列长度，感知阵列的长度影响能够达到的最大定位距离，感知阵列的密度则影响近距离范围内的定位精度。本项目研究为仿生鱼侧线感知系统设计提供了基础理论与方法，为潜航器避障、姿态控制等提供了一种流场环境感知实现手段。