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波动鳍推进水下作业机器人的研究旨在为集低噪声、环境友好、高运动稳定性以及高抗扰性等特性于一体的新一代水下机器人的设计与控制提供重要的理论基础和技术支撑。本文针对波动鳍推进水下作业机器人的模块化系统设计、基本运动控制、路径跟踪控制以及悬停控制等方面展开研究工作，论文的主要内容如下： 

一、以黑魔鬼刀鱼为仿生对象，设计了一种能实现多种波动模式的波动鳍水下推进器。基于长鳍波动运动学分析，设计开发了其驱动系统。波动鳍水下推进器具有独立的供电和控制组件，可作为标准推进模块安装在水下运动平台上。通过长鳍波动控制实验和水下游动实验验证了该波动鳍水下推进器系统设计的有效性。 

二、针对波动鳍推进水下作业机器人基本运动控制问题展开研究。基于波动鳍水下推进器构建了波动鳍推进水下作业机器人，并建立了波动鳍推进水下作业机器人系统模型。通过控制波动鳍推进水下作业机器人两侧长鳍行波参数，实现了进退、转向、浮潜等多模态运动以及航向和深度闭环运动控制，实验结果显示波动鳍推进水下作业机器人具有良好的运动能力。 

三、针对波动鳍推进水下作业机器人平面路径跟踪控制问题，提出一种基于反步法的路径跟踪控制方法。基于视线导航原理给出当前需要趋向的视线点，并根据视线点建立跟踪误差微分方程。基于反步法设计了非线性控制器，可输出水下作业机器人趋于视线点所需的推进力和力矩控制量，并基于李雅普诺夫稳定性判据证明了控制器全局渐进稳定性。通过仿真和实验对提出的路径跟踪控制方法进行了验证。 

四、针对波动鳍推进水下作业机器人三维螺旋线路径规划与跟踪控制问题展开研究，提出一种路径规划和路径跟踪协调控制框架。路径规划器根据目标位置及约束条件规划三维螺旋线路径。路径跟踪协调控制器根据水下作业机器人的当前位姿及规划路径实时协调游速、航向和深度三个控制通道设定值，并通过三个自抗扰控制器分别对游速、航向及深度进行闭环控制。实验结果验证了提出的路径规划和路径跟踪协调控制框架的有效性，实现了波动鳍推进水下作业机器人水下三维螺旋线路径跟踪控制。 

五、针对波动鳍推进水下作业机器人自主悬停控制问题，提出一种基于视觉伺服的悬停控制方法。该方法通过双目视觉图像处理获取目标图像特征并进行目标位置估计，基于图像雅可比矩阵将图像特征误差及距离误差映射为保持悬停位姿所需的期望运动速度，利用跟踪微分器对水下作业机器人运动速度进行估计，并设计速度控制器使水下作业机器人达到期望运动速度。数值仿真和实验结果显示所提悬停控制方法能够控制波动鳍推进水下作业机器人实现自主悬停。 

The research on the underwater vehicle-manipulator system (UVMS) propelled by undulatory fins aims to lay theoretical and technical foundations for design and control of a new generation of underwater robots with low noise, environmental friendliness, high motion stability, and high anti-disturbance performance. This thesis focuses on the modular system design, basic motion control, path following control and hovering control for an UVMS propelled by undulatory fins. The main contents of this thesis are as follows.

Firstly, mimicking the undulatory propulsion mode of knifefish, a biomimetic underwater propulsor with an undulatory fin is developed. Based on the kinematics analysis of the undulatory fin, a driver system is developed to achieve the motion control of the undulatory fin. The underwater propulsor has independent power supply and control components, allowing it to be installed as a standard propulsion module on underwater robotic platforms. The effectiveness of the system design is validated by undulatory fin control experiments and swimming experiments.

Secondly, we address the basic motion control problems for an UVMS propelled by undulatory fins. Based on modular underwater propulsors, an UVMS propelled by undulatory fins is fabricated. Then the system models of the UVMS are built. Multiple motion patterns such as marching, receding, turning, submerging and surfacing are achieved. Besides, heading and depth control experiments are performed. Experimental results show that the UVMS propelled by undulatory fins has good mobility.

Thirdly, in order to solve the problem of planar path following control for the UVMS propelled by undulatory fins, a backstepping-based path following control method is proposed. A line-of-sight guidance system is implemented to deduce the foresight point, followed by the establishment of the tracking error differential equation. A backstepping controller is design to output required propulsive force and torque. The stability of the backstepping controller is analyzed and guaranteed by the Lyapunov stability theory. Simulations and experimental results illustrate the performance of the proposed path following control method.

Fourthly, 3-D helical path planning and path following of the UVMS propelled by undulatory fins are studied. A path planner is designed to provide a 3-D helical path according to the target position and the specific constraint conditions. Furthermore, a path following coordination controller coordinates the reference speed, heading and depth according to current position and heading of the UVMS and the planned path. Three active disturbance rejection controllers are designed to force the UVMS to track the reference speed, heading, and depth, respectively. Experiments are given to show the validity of the proposed method.

Finally, aiming at the autonomous hovering control for the UVMS propelled by undulatory fins, a vision-based hovering control method is proposed. The target position and actual visual feature are obtained by binocular vision image processing. A hovering controller is proposed to map the visual feature error and distance error to the desired velocity based on image Jacobian. Furthermore, a tracking differentiator is used to output the velocity estimation of the UVMS. A velocity controller is designed so that the UVMS could reach the desired velocity. Simulations and experimental results demonstrate the validity of the proposed hovering control method.