飞机防滑刹车控制系统的结合系数研究

【作者】 徐丽；

【导师】 李玉忍；

【作者基本信息】 西北工业大学 ， 电力电子与电力传动， 2007， 硕士

【摘要】 防滑刹车系统是飞机重要的机载设备，对飞机的起飞、安全着陆起着重要的作用。本文分别采用了四种方法来对地面结合系数—滑移率的关系进行了分析研究。一、针对Pacejka模型讨论模型中参数B、C、D的取值范围，以及对Pacejka模型曲线形状的影响；二、用神经网络的BP算法解决地面结合系数—滑移率的非线性特性，通过对防滑惯性台测得的地面结合系数—滑移率的数据进行拟合，寻求最优的结合系数—滑移率的关系；三、采用模糊控制方法来处理结合系数与滑移率的非线性关系。进行在线识别，设计模糊控制器，确定模糊控制规则，从而寻求到最优的关系曲线；四、针对结合系数无法直接测量得到的问题，提出了一种利用最小二乘法对结合系数与滑移率关系式中的参数进行在线辨识的方法。 最后在MATLAB／SIMULINK下进行系统仿真，并将仿真结果进行分析比较。仿真结果表明，采用智能方法的系统在刹停时间、刹停距离以及刹车效率方面均优于采用数值计算方法的系统。更多还原

【Abstract】 In the modern aircraft, the anti-skid braking system is one of the main airborne devices and plays a very important role in safely takeoff and landing.The ground adhesion coefficient-slip relation is analysed and researched by four methods. Firstly,aiming at Pacejka model ,the range of the parameter B,C,D and effects on the Pacejka curves shapes is discussed . Secondly, non-linearity characteristic of ground adhesion coefficient-slip is resolved by the BP algdrithm of the neural network, the datum measured on the test-bed are drew up, and relation of coefficient-slip is sought finely.Thirdly,using fuzzy control to resolve the non-linearity characteristic of groud adhesion coefficient-slip.By identifying on line,designing a fuzzy controller and defining the rules of fuzzy control, the curve of the relationship of coefficient-slip is sought finely.Forthly,An on-line parameter identification method that is least-square is presented because the coefficient between tyre and runway hasn’t been got.Finally,simulating the system in the MATLAB/SEMULINK,then analyzing and comparing the results of simulating.The results indicate that the system which adopts the method of artificial intelligence and abilities is more excellent than the system that adopts the method of mathematic calculating.更多还原