Adaptive dynamic surface control of NSVs with input saturation using a disturbance observer

An adaptive dynamic surface control(DSC)scheme is proposed for the multi-input and multi-output(MIMO)attitude motion of near-space vehicles(NSVs)in the presence of external disturbance,system uncertainty and input saturation.The external disturbance and the system uncertainty are efficiently tackled using a Nussbaum disturbance observer(NDO),and the adaptive controller is constructed by combining the dynamic surface control technique to handle the problem of‘‘explosion of complexity’’inherent in the conventional backstepping method.For handling the input saturation,an auxiliary system is designed with the same order as that of the studied MIMO attitude system.Using the error between the saturation input and the desired control input as the input of the designed auxiliary system,a series of signals are generated to compensate for the effect of the saturation in the dynamic surface control design.It is proved that the developed control scheme can guarantee that all signals of the closed-loop control system are semi-globally uniformly bounded.Finally,simulation results illustrate that the proposed control scheme can achieve satisfactory tracking performance under the composite effects of the input saturation and the external disturbance.     

控制输入受限情况下卫星姿态的鲁棒自适应控制

卫星通常工作在各种扰动环境中,包括参数不确定性和非参数不确定性。工程实践中碰到的另一个重要问题是控制输入受限。考虑存在参数不确定性和非参数不确定性,研究控制输入受限情况下卫星的姿态控制问题,设计了一种鲁棒自适应控制器,证明了姿态控制系统是全局一致最终有界稳定。仿真结果验证了该控制器的有效性。     

检测和控制技术在钢管自动化生产中的应用

本文介绍了基于分布式控制方案的自动化生产线的设计,利用检测和控制技术,实现自动化生产的功能。实现钢板的卷制;完成钢管在不同工位的上料和下料,实现纵缝和环缝的焊接;应用传感器检测钢管的位置及长度,完成钢管在传送线上的自动传送,自动完成在存储区的存人与取出。应用表明,提高了生产效率,节省了人力物力,使得生产更加安全可靠。     

JMASS环境下的飞行仿真组件集成研究

简要介绍了联合建模与仿真系统(JMASS)的基本概念,分析了JMASS的结构和组成。进一步以一个飞行仿真组件的集成为实例,阐述了如何进行基于JMASS仿真环境的仿真子系统开发,特别研究了如何给已有仿真组件增加设计专门针对JMASS环境而的接口的技术,使现有组件能够顺利集成到JMASS环境下,并使之正确运行。     

基于自适应模糊输出观测器的非线性系统鲁棒故障检测

针对一般非线性系统的故障检测,从工程应用的角度提出了一种基于自适应模糊输出观测器的非线性系统鲁棒故障检测方法。该方法以自适应模糊系统构造未知非线性模型的输出观测器,在充分考虑外加噪声干扰和系统误差的情况下,通过对一般反向传播学习算法进行改进,提出采用鲁棒反向传播学习算法调整观测器参数以辩识系统输出,再结合阈值故障检测策略检测系统故障。为保证算法具有较快的收敛速度,本文给出了根据模糊规则确定算法初始参数的选择方法并证明了算法的收敛性。仿真结果表明,对一般非线性系统故障检测,该方法具有有效性和实时性,以及对噪声干扰和系统误差的鲁棒性。     

Disturbance observer-based robust guidance for Mars atmospheric entry with input saturation

With low-lifting capability taken into account,a robust guidance law for Mars entry vehicles with low lift-to-drag ratios,such as Mars Science Laboratory(MSL),is presented.Consider the nonlinear term in the drag dynamic equation and bounded disturbances as a lumped disturbance,and design a linear disturbance observer(DOB)to estimate it.With the consideration of the control input saturation,an innovative sliding surface and a virtual system are introduced to design the guidance law.Analyses of disturbance observer performance and Lyapunov-based transient performance are also presented.It is shown that the drag tracking error can be adjustable by explicit choices of design parameters.Simulation results confirm the effectiveness of the proposed guidance law.