【作者】 保宏；

【导师】 段宝岩；

【作者基本信息】 西安电子科技大学 ， 机械制造及其自动化， 2005， 博士

【摘要】 针对新一代大射电望远镜馈源支撑结构的特点,主要研究了舱索结构粗调系统的主动控制,舱内Stewart精调平台的动力学分析与优化,以及粗—精两级动力学耦合与复合控制问题。完成的主要工作和取得的研究结论归纳如下:1.针对舱索结构的大柔性、变结构、以及多输入多输出的特点,建立了粗调系统的控制模型,推导了六根大跨度柔索输入与输出间关系矩阵的递推公式,提出了基于神经网络的一步向前自适应控制策略与方法。将该方法应用于LT50 m模型的实际实验中,取得了满意的试验结果,验证了策略与方法的可行性、有效性。2.针对舱索系统的惯性主要集中在馈源舱上的特点,基于牛顿欧拉方程建立了馈源舱动力学模型,将模型误差视为外部对馈源舱的扰动,提出了具有多输入多输出和强鲁棒性自抗扰滑模控制算器,得到了馈源舱非稳态模型下各悬索的控制拉力,数值计算结果说明了该方法的有效性和合理性。3.针对复杂系统动力学方程的解不能显示表达,导致控制与结构设计同步优化时参数敏度分析困难这一问题,通过建立适当的控制器,将对复杂动力学方程的敏度分析转化为对简单线性方程的敏度分析,并以6自由度的Stewart平台为例,介绍了控制与结构设计同步优化的过程。4.基于牛顿欧拉方程,建立了柔性支撑下Stewart平台动力学模型,在已知动平台运动规划的条件下,对Stewart平台和舱索系统同时进行了动力学分析,研究了粗—精两级动力学耦合问题。并采用H∞优化理论,分析了下平台不同的质量对舱索系统振动所产生的影响,初步探讨了动平台质量和馈源舱质量最小质量比的条件。5.针对舱索系统滞后性的特点,建立了测量点的运动学数学模型,并采用H∞滤波器,有效的给出测量点状态变量的数值,通过与LT50m实验的实测数据比较,说明该模型的合理性。在此基础上,提出了柔性支撑下Stewart平台控制器,数值计算结果说明该方法可以有效的抑制馈源舱振动对Stewart动平台定位精度的影响。更多还原

【Abstract】 In this dissertation, considering the special character tics for the next generationlarge radio telescope (LT), active control of cable-cabin system, dynamical andoptimal analysis, dynamical couple between the coarse subsystem and the fine tuningsubsystem, and compound control are studied. In the follows, the main research workscan be described as.1, Considering the special characteristics of the large flexible of long-cablestructures, various structures, and the strong coupling among cables with multiple inputmultiple output (MIMO), control model first is developed. Then, a recursively algorithmof MIMO matrix between input cable and out cable is deduced. In addition,one-step-ahead adaptive control methodology with neural network of nonlinear systemsis presented. Finally, practical LT 50m-model experiment is executed to demonstrate thefeasibility and validity of the methodology.2, Based on Newton-Euler method a dynamic model for the cabin is built, sincemainly inertia of cable-cabin system is concentrated on the cabin. Model error includingwind is considered as an unknown disturbance to the cabin. An reject disturbance slidemode controller is proposed with high robust and MIMO and the forces of the cables isget based non-stationary model.3, Due to analytic solves of the complex dynamic model can not be obtain,integrated optimal design of structure and control system is very difficult using thesensitivities. Considering the problem, a method is developed based on buildingcontroller. The sensitivity analysis of the complex system is transformed into thesensitivity analysis of the linear system. The process of the simultaneous optimizationof control and structural for the Stewart platform is introduced to demonstrate thevalidity of the method.4, The dynamic model of the Stewart platform is presented with the flexiblesupporting based on the principle of Newton-Euler. An integrated dynamic analysis ofthe cable-cabin subsystem and the fine tuning Stewart platform and dynamic couplingbetween the two subsystems is studied. The effecting of the cabin-vibration on differentmasses of moving platform is discussed using H∞theory.5,Considering the special characteristic of the delay of long-cable structure , akinematical model of measurement-point is built to obtain exact states values ofmeasure points involves displacement, velocity, acceleration based on H∞filter theory.The comparison dates between LT50m experiment shows the measurement model isvalidity. A controller of the Stewart platform is presented with the flexible supporting.The simulation results shows that the effecting of the cabin vibration on trackingprecision of the Stewart platform is restrained effectively.更多还原