【作者】 李家宁；

【导师】 徐波；

【作者基本信息】 南京航空航天大学 ， 导航、制导与控制， 2009， 硕士

【摘要】 平流层飞艇具有很高的民用和军用价值,目前已成为各国新兴的研究热点。本论文主要研究了平流层飞艇的动力学模型和定点保持的相关问题,对飞艇的定点保持采用了滑模变结构和Backstepping两种不同的控制方法。所进行的研究与设计工作主要包括以下几个方面:1.对飞艇进行受力分析,着重分析了附加质量力、空气动力和力矩,分别给出了它们的一种近似的计算模型。推导了飞艇六自由度运动的动力学模型,然后结合运动学方程组,建立了飞艇完整的数学模型。2.针对平流层飞艇定点控制的特点,将飞艇模型按水平面和垂直面分别进行简化。因而,定点控制可以划分为水平面内的定位控制和垂直面内的定高控制。同时为了设计控制器的需要,采用反馈线性化的方法,将这两个非线性模型分别进行输入输出线性化。3.采用滑模变结构方法分别对飞艇水平面模型设计了定位控制器和对垂直面模型设计了定高控制器。考虑平流层风向和风速相对比较稳定,建立了水平风的扰动模型,在飞艇存在水平风干扰和不确定性模型参数干扰的情况下,设计了一种具有鲁棒性的滑模变结构的定位控制器和定高控制器来实现定点功能。4.采用Backstepping方法分别对飞艇水平面模型设计了定位控制器和对垂直面模型设计了定高控制器。在飞艇存在水平风干扰和不确定性模型参数干扰的情况下设计了一种基于Backstepping的定位控制器和定高控制器来实现定点功能。5.给出了两种控制方法的仿真结果并进行了比较分析。通过比较发现两种方法都可以实现控制目标。在水平面定位控制时滑模控制方法具有稳定时间短,消耗能量较少的优点,而Backstepping方法具有较好的动态性;在垂直面定高控制时,Backstepping方法则具有较短的稳定时间,能量消耗较少。6.结合Backstepping方法对飞艇的航迹跟踪作了初步研究。更多还原

【Abstract】 Presently, there is a strong interest in developing stratospheric airships. Stratospheric airships which are High-altitude long-range have wide applications in the fields of transportation, observation, and telecommunication services, etc. This paper researches some questions about dynamic model and station-keeping control. Variable structure control and Backstepping control method are applied to control of airship in stationkeeping mode. The works of study and design are as follow:1. Based on analysing the forces acting on the stratospheric airship, particularly, the added mass force, air force and buoyancy are studied and three computing models are presented. A nonlinear model which is a six degree-of-freedom dynamic equations together with motion equations compose the whole airship mathematical model.2. Considering characteristic of stratospheric airship station-keeping control, the airship model is simplified to horizontal and vertical model. Thus, station-keeping control could be divided into horizontal position control and vertical high control. Use feedback linearization to linearize both nonlinear models.3. Applying variable structure control to design position controller in horizontal model and high controller in vertical model. Considering stratospheric wind speed is both relative stable, horizontal wind disturbance model is established. In the existence of parameters uncertainty and wind disturbance, a sliding mode controller is designed to achieve position control and high control.4. Applying Backstepping control to design position controller in horizontal model and high controller in vertical model. In the existence of parameters uncertainty of the model and wind disturbance, a Backstepping controller is designed to achieve position control and high control.5. The simulation results of both control methods are given and compared. By comparing both methods can be found to achieve respective control goal. In the horizontal position control, sliding mode control method has a relative short stable time and less control energy, while Backstepping control has dynamic effect. In the vertical high control, Backstepping control method has a relative short stable time and less control energy.6. Utilize Backstepping method to design airship trajectory tracking controller.更多还原