自适应变论域模糊控制器在结构振动控制中的应用

大挠性航天结构具有复杂的动力学特性,建立其精确的数学模型是很困难的,模糊控制不需要精确的数学模型,但是模糊控制的主要缺陷是精度不太高,自适应能力有限,易产生振荡现象。变论域自适应模糊控制是改变模糊控制性能的主要方法之一,针对自适应变论域模糊控制器的稳定性设计这一难题,将输入和输出的隶属度函数分别用论域值表示成解析形式,引进李亚谱诺夫函数,设计了输入和输出的隶属度函数论域值的自适应律,针对大型航天桁架结构振动控制的仿真,结果表明设计的变论域模糊控制器是可行的。

Active Control of Structural Vibration Using A Fuzzy Control Method Based on Adaptive Scaling Universes of Discourse

Large flexible space structures are complex in structural dynamic characteristics.Fuzzy control does not need an accurate mathematical model.But precision of a conventional fuzzy controller is not good,and its adaptive ability is limited.It can make the system surge.Scaling universes of disourse is an effective method to improve the performance of a fuzzy controller.The authors aim at a difficult problem of designing a stable adaptive controller based on scaling universes of discourse,let its input membership function and output membership function be denoted as input universes of discouvse and the center value of the output membership function,then adopt a kind of Lyapunov function,design a adaptive law of input universes of discourse and the center value of the output membership function.The structural vibration control of a truss is simulated.And the results show that the proposed method is feasible for vibration control of large flexible space structures.