摘要：水下机器人的工作环境一般都是复杂的海洋环境，由于海洋环境中存在各种不确定因素，会影响水下机器人的运动控制性能，从而影响完成水下任务的效率。因此，要对水下机器人进行稳定精确的控制，关键问题就是运动控制器的设计，这也是本文的主要研究内容。

首先，本论文通过借鉴与课题相关的国内外优秀的研究成果，确定了水下机器人的总体结构和推进器的数量；然后对水下机器人进行详细的受力分析，得出水下机器人在各方向的受力和力矩，之后利用机体坐标系和地面坐标系两个坐标系间的坐标变换，构建了水下机器人的非线性运动模型。在MATLAB环境中，使用S-函数实现模型，并进行了开环仿真验证。

然后对水下机器人的运动控制器进行设计和仿真。水下机器人的运动特性是非线性、强耦合的，其数学模型也是一个典型的非线性系统模型。而Backstepping（反步法）控制方法是一种强有力的工具，对非线性系统模型拥有较强的鲁棒性。因此，本文设计了一种基于Backstepping的运动控制器，实现对水下机器人垂直面的运动控制，并能够保证闭环系统稳定。最后通过仿真结果显示，该控制器能够对水下机器人进行有效的变深跟踪控制，同时具有良好的控制性能。

关键词：水下机器人；非线性运动模型；S-函数；Backstepping控制方法；垂直面运动控制

ABSTRACT：Generally,underwater vhicles are working in a complex marine environment.There are various uncertain factors in the marine environment, which will affect the motion control performance of underwater vehicles and the efficiency of underwater operation. In order to control the underwater vehicle accurately and stably, the key problem is the design of the motion controller.This is also the main research content of this paper.

Firstly,the general structure of the underwater vehicle and the number of the propeller are determined, after learning from the excellent research results related to the subject at home and abroad.Through the detailed force analysis of the underwater vehicle, the forces and torques of the underwater vehicle in all directions are obtained. Then we use the transformation between the body coordinate system and the ground coordinate system to build the underwater vehicle’s motion control model.The S-function of MATLAB software is used to realize the model.Meanwhile,open-loop simulations are carried out to verify the correction of the model.

Then the motion controller of the underwater vehicle is designed and simulated. The motion characteristics of the underwater vehicle are nonlinear and strongly coupled, and its mathematical model is also a typical nonlinear system model. The Backstepping control method is a powerful tool which has strong robustness to the nonlinear system.  Therefore, a Backstepping-based motion controller is designed in this paper to realize the variable depth control and to stabilize the closed-loop system.At last, the simulation results show that this controller can control the underwater vehicle’s depth tracking effectively and has good control performance at the same time.

Key words: Underwater Vehicles; Nonlinear motion model; S-function；Backstepping control method; vertical plane motion control

目录

第一章绪论 1

1.1引言 1

1.2水下机器人的研究概况及发展趋势 1

1.2.1水下机器人的研究概况 1

1.2.2水下机器人的发展趋势 3

1.3水下机器人运动控制方法概述 4

1.3.1传统PID控制