【作者】 高剑；

【导师】 徐德民；

【作者基本信息】 西北工业大学 ， 控制理论与控制工程， 2004， 硕士

【摘要】 本论文系统研究了自主式水下航行器的建模、非线性自适应滑模控制、以及深度调整和水平面导引方法等问题，具体成果和创新点如下 1、根据流体力学理论，建立了螺旋桨推进器的动态模型，它以螺旋桨来流速度v_p和螺旋桨转速n为状态变量，以电机施加转矩τ为输入，螺旋桨推力T和转矩Q为输出。 2、针对自主式水下航行器非线性强、模型参数获取困难的问题，提出了非线性自适应滑模控制，从理论上证明了它的全局渐近稳定性。其特点是在滑模控制的基础上引入自适应机制，在线估计不确定参数，从而消除参数不确定性对系统性能的影响，在保证鲁棒性的基础上减小了滑模控制附加项的幅值。考虑到可能出现的参数漂移，提出了自适应律的两点改进。 3、研究了自主式水下航行器的速度／位置跟踪控制问题。在推进器动态模型的基础上，采用滑模控制的方法，由速度／位置误差获得期望推力，再通过求解包括来流速度的二次方程得到期望螺旋桨转速。通过对比未考虑与考虑推进器动态模型两种情况的控制结果，说明该模型的重要性。 4、提出基于模糊推理系统的自主式水下航行器深度调整策略。该方法建立在对水下航行器的机动性能和水下环境等先验知识的基础上，突出优点是易于理解、操作和修改。 5、研究了自主式水下航行器水平面运动的“视线”导引算法，并考虑了广泛存在的定常海流对水平面导引轨迹的影响。在速度和位置测量的基础上，设计了海流速度的观测器，并对“视线”导引进行修正，使水下航行器能够沿“视线”航行。本论文还研究了一种基于极坐标变换的“视线”导引，并与前面的方法进行了对比。更多还原

【Abstract】 The continual development of computer technology has enabled the expansion of advanced control into the field of autonomous underwater vehicles (AUVs), where potential uses include oceanographic research, environmental monitoring and military mine countermeasures. In this dissertation, through computer simulation, the problems of modeling, control and guidance of AUVs are presented.The first part of this dissertation addresses the problem of dynamically modeling of AUVs, and derives thrusters’ two-dimension nonlinear dynamic model, which has axial flow speed and propeller rotational velocity as two state variables, voltage or current of motor as inputs, and thruster force and torque as output.The second part focuses on the nonlinear adaptive sliding mode control of AUVs in diving plane and steering plane. The requirement for having a simple controller which performs satisfactorily in the presence of dynamical uncertainties calls for a design using the sliding mode approach. In this controller, online parameters estimating algorithm is added to classical sliding mode controller to achieve both robustness and adaptability, to prevent noise and disturbances from causing parameter drift, a dead-zone is added to shut adaptation off for small tracking errors, and the adaptation law is modified to guarantee the estimated parameters in previously known ranges.The third part is devoted to the problem of speed/position’s tracking control using sliding mode control approach. A cascaded architecture is adopted, where desired propeller rate of revolution is generated by solving a static 2nd order equation with a parameter of desired thrust force, which is the input of the speed/position tracking control.In the last part, depth schedule strategy based on fuzzy inference system (FIS), and line-of-sight guidance in horizontal plane in the presence of unknown current are studied.更多还原