【作者】 戚增坤；

【导师】 孙尧；

【作者基本信息】 哈尔滨工程大学 ， 导航、制导与控制， 2010， 博士

【摘要】 人类对客观世界认知和改造的历史过程,是一个由低级到高级,由简单到复杂,由表及里的纵深发展过程,在控制领域中更是如此。由于人们对实际生产过程的精度要求越来越高以及受控对象的不断复杂化,原有的线性控制理论已不能满足需要,因此相继诞生了一系列的非线性控制方法,如变结构控制、自适应控制、鲁棒控制等。突变控制是非线性控制的一种,其主要目的在于控制系统在平稳输入情况下产生的输出跳变问题。本文将致力于探索如何使突变理论同控制技术相结合,形成一套突变控制的方法,并试探性地应用到船舶横摇运动及稳定性控制中去,主要成果如下:首先,对势函数具有多输入单输出形式的非线性系统,根据其输入变量的数目不同,分别提出了折叠突变建模、尖点突变建模、燕尾突变建模和蝴蝶突变建模的通用方法,并根据各个系统不同的突变特点,针对性的设计了线性控制器、非线性控制器与基于冲失滤波器辅助反馈的控制器对突变进行控制。其次,将折叠突变建模的通用方法引入到船舶非线性横摇运动中,在定性地得出船舶非线性横摇运动具有突变特性后,采用非线性振动分析中的多尺度法对横摇方程加以解析,得出了横摇运动的幅频响应方程,并以数值仿真验证了横摇突变特性的存在。最后分别用线性控制器和非线性控制器对船舶非线性横摇运动的突变特性进行了控制,仿真结果表明这两种控制方法效果明显,能有效抑制船舶横摇运动时突变现象的发生。然后,将尖点突变建模的通用方法引入到船舶无阻尼静水横摇运动中,详细地讨论了船舶倾覆的过程,并在对其突变流形解析的基础上得到了突变发生的临界条件。阐明了恢复力系数与横摇自然频率的改变是船舶无阻尼静水横摇运动突变发生的原因,并分别设计了非线性控制器和冲失滤波器进行突变控制,经仿真证明控制器效果明显。最后,将蝴蝶突变建模的通用方法引入到船舶在长峰波海浪中的参数横摇运动中,在用突变模型定性地证明了其突变特性之后,采用多尺度法对横摇方程进行解析,定量地得出了船舶参数横摇的突变特性,并设计了线性反馈控制器,在讨论了控制参数选取范围的情况下,对横摇运动进行突变控制,仿真结果表明控制器简单有效。更多还原

【Abstract】 The history course of human cognize and transform the objective world is a process which experience from lower to higher, simple to complex, outside to the inside, either the control area. For demanding higher accuracy in actual production process and the increasing complexity of the controlled object, the original linear control theory has been unable to meet the needs of people. So, a series of nonlinear control method were born in succession, such as variable structure control, adaptive control, robust control, etc.Catastrophe control theory is a kind of nonlinear control theory, which main purpose is to control the output’s jumping problem of the system when inputs are smooth. This article will explore how to make the catastrophe theory combined with the control technology to create a set of catastrophe control methods, and tentatively applied to the ship rolling motion and stability control.The main work are the as follows:First, for a nonlinear system which potential energy function has multi-input and single-output style, catastrophe model can be built according to the numbers of input variables.They are fold, cusp, swallowtail and butterfly catastrophe models. And in accordance with the different characteristics of each system, linear controller, nonlinear controller and washout controller were designed to control the catastrophe phenomena.Second, fold catastrophe model was introduced into the capsizing of nonlinear ship roll movement, then multi-scale method was used to get the amplitude frequency response equation, and the catastrohe characteristics were proved by numerical simulation. Finally, linear and nonlinear controllers were designed to control the catastrophe phenomena, and the effectiveness was proved by simulation.Third, cusp catastrophe model was made to analyse the course of ship roll motion without damping in hydrostatic water, and the process of ship capsize caused by parameters changes were discussed in detail. Critical conditions were also discussed and the catastrophe cause was clarified. Finally, nonlinear controller and washout controller were designed.At last, the ship’s nonlinear rolling motion under excition by longitudinal wave was fitted into butterfly catastrophe model, and the multi-scale method was used to get the catastrohe characteristics. Then the linear feedback controller was designed to restrain the catastrophe, and the result was great by simulation.更多还原