海流干扰下的欠驱动AUV三维路径跟踪控制

为解决存在海流干扰和模型不确定性情况下欠驱动自主水下航行器(AUV)的三维路径跟踪控制问题,首先在Serret-Frenet坐标系下,基于虚拟向导建立了跟踪误差模型.然后,在运动学控制器中基于李雅普诺夫(Lyapunov)理论和反步法设计具有自适应律的虚拟向导和一种改进的积分视线法(ILOS)导引律,克服了海流的干扰并减少了超调.应用反步自适应滑模控制(BASMC)理论设计动力学控制器,保证了系统的稳定性和鲁棒性.最后,应用非线性级联理论证明了整个控制系统的闭环稳定性.仿真结果表明:基于AUV与流体的相对速度来实现的控制律,便于工程应用.该控制器能够有效克服海流和模型不确定的影响,实现对三维路径的跟踪.     

Trajectory tracking control for underactuated unmanned surface vehicles with dynamic uncertainties

The trajectory tracking control problem for underactuated unmanned surface vehicles(USV) was addressed, and the control system took account of the uncertain influences induced by model perturbation, external disturbance, etc. By introducing the reference, trajectory was generated by a virtual USV, and the error equation of trajectory tracking for USV was obtained, which transformed the tracking problem of underactuated USV into the stabilization problem of the trajectory tracking error equation. A backstepping adaptive sliding mode controller was proposed based on backstepping technology and method of dynamic slide model control. By means of theoretical analysis, it is proved that the proposed controller ensures that the solutions of closed loop system have the ultimate boundedness property. Simulation results are presented to illustrate the effectiveness of the proposed controller.     

基于Razumikhin方法的非线性时滞系统的自适应模糊控制设计

【中文摘要】 为研究一类单输入单输出非线性时滞系统的自适应跟踪控制问题,基于Lyapunov Razumikhin泛函方法给出了一种新的自适应模糊控制器设计方法,利用模糊逻辑系统来估计系统中未知的非线性函数,用backstepping方法来设计跟踪控制器。所设计的自适应模糊控制器能确保所有的闭环信号有界,同时系统输出收敛到所期望轨线的一个小邻域中。仿真例子表明文中所提出的控制方案能够有效地跟踪给定的参考信号。     

FDI攻击下非线性多智能体系统分布式无模型自适应控制

为研究受到虚假数据注入攻击的单输入单输出非线性多智能体系统的分布式无模型自适应控制问题,提出了一种新的分布式动态线性化方法, 以获得非线性多智能体的等效线性数据模型。与现有多智能体的分布式无模型自适应控制在控制器设计中有所不同, 本文设计的控制器不需要网络拓扑结构的信息, 仅使用系统的输入输出数据。仿真算例验证了所提出的分布式无模型自适应控制算法可以实现多智能体系统的均方有界趋同控制。算法保证了多智能体系统在受到网络攻击时可以实现趋同控制目标。     

Backstepping Adaptive Controller of Electro-Hydraulic Servo System of Continuous Rotary Motor

In order to consider the influence of the continuous rotary motor electro-hydraulic servo system parameters change on its performance,the design method of backstepping adaptive controller is put forward.The mathematical model of electro-hydraulic servo system of continuous rotary motor is established,and the whole system is decomposed into several lower order subsystems,and the virtual control signal is designed for each subsystem from the final subsystem with motor angular displacement to the subsystem with system control input voltage. Based on Lyapunov method and the backstepping theory,an adaptive backstepping controller is designed with the changed parameters adaptive law. It is proved that the system reaches the global asymptotic stability,and the system tracking error asymptotically tends to zero. The simulation results show that the backstepping adaptive controller based on the adaptive law of the changed parameters can improve the performance of continuous rotary motor,and the proposed control strategy is feasible.     

Bottom-following control for an underactuated unmanned undersea vehicle using integral-terminal sliding mode control

The bottom-following problem of an underactuated unmanned undersea vehicle(UUV) is addressed. A robust nonlinear controller is developed by using integral-terminal sliding mode control(ITSMC), which can exponentially drive an UUV onto a predefined path at a constant forward speed. The kinematic error equations are first derived in the Serret-Frenet frame. Using the line of sight(LOS) method, Lyapunov's direct technique and tracking differentiator, the guidance law is established. Then, the kinematic controller, the guidance law, is expanded to cope with vehicle dynamics by resorting to introduce two integral-terminal sliding surfaces. Robustness to parameter perturbation is addressed by incorporating the reaching laws associated with the upper bound of the parameter perturbation. The proposed control law can guarantee that all error signals globally exponentially converge to the origin. Finally, a series of numerical simulation results are presented and discussed. In these simulations, wave, constant unknown ocean currents(for the purposes of the controller) and the parameter perturbation are added to illustrate the robustness and effectiveness of the bottom-following control scheme.     

具有未知死区的SISO非仿射非线性系统间接自适应模糊控制

为了解决含有未知死区输入特性的SISO非仿射非线性系统的跟踪控制问题,提出了基于模糊自适应方法的控制器设计方案,把未知死区分解为一个线性项和一个扰动类似项,当系统状态可测时,利用模糊逻辑系统设计间接自适应模糊控制器,并结合跟踪误差信息设计自适应律;系统状态不可测时,通过引入误差观测器估计的状态变量,设计了间接自适应模糊输出反馈控制器．理论论证过程说明两种控制器能使系统的跟踪误差最终收敛到零的某一邻域,且闭环系统所有信号均有界. 仿真实验结果表明利用所设计控制方案可以使系统完成跟踪控制任务．     

具有参数不确定被动力伺服系统的反步控制

针对被动式力伺服系统的参数变化和多余力矩问题,在建立系统非线性模型的基础上,设计一种自适应反步控制器.并利用Lyapunov稳定性定理证明了设计控制器的稳定性.该控制器考虑了系统主要参数变化和承载系统的扰动,将系统方程重组成多个虚拟子系统,利用反步控制思想对每个虚拟系统设计虚拟控制量,通过反步递推得到含有参数变化与承载系统扰动的非线性控制器.仿真结果表明:与传统控制器相比,该自适应反步控制器能更好地抑制多余力矩,证明了所设计控制器的有效性.     

欠驱动AUV的鲁棒位置跟踪控制

为了实现具有参数不确定性和外界干扰的欠驱动AUV的水平面鲁棒位置跟踪,基于李雅普诺夫理论,使用反步法设计了一个非线性控制器,并利用滑模控制方法提高控制系统的鲁棒性;为了检验该控制器的性能,选择有时变参考速度的正弦曲线作为参考轨迹,在控制输入受限的情况下,对具有参数不确定性和外界干扰的欠驱动AUV系统进行了数值仿真,结果表明本文设计的控制器能很好地实现欠驱动AUV的水平面位置跟踪控制,具有很强的鲁棒性。     

非线性不确定系统的自适应模糊跟踪控制

针对一类带有未知非线性函数的非线性不确定系统,提出了一种新的自适应模糊跟踪控制方案。模糊逻辑系统用于系统中的未知的非线性函数建模,然后基于backstepping方法和自适应技术设计模糊自适应控制器。所设计的模糊自适应控制器确保闭环系统的所有信号是一致有界的,同时跟踪误差收敛到原点的一个充分小的邻域内。另外所设计的控制器不涉及模糊基向量函数,因此所提出的控制器用于控制系统时,将极大地降低系统的在线计算负担。仿真算例验证了所提出方法的有效性。     

Adaptive fuzzy tracking control for a class of switched MIMO nonlinear systems

An adaptive fuzzy tracking control scheme is presented for a class of switched multi-input-multi-output (MIMO) nonlinear systems with disturbances under arbitrary switching.Adaptive fuzzy systems are e...     

自主水下航行器轴向运动的自适应反演滑模控制

研究了自主水下航行器在未知海流作用下的轴向运动跟踪控制问题,采用非线性反演设计技术,引入自适应机制在线估计未知海流速度和模型参数,用滑模控制克服系统中的未建模动态特性,保证了轴向位置跟踪误差的全局渐近稳定性。仿真结果表明,该自适应反演滑模控制具有良好的鲁棒性和自适应性。     

一类非线性非严格反馈系统的间接自适应神经网络控制

针对一类非严格反馈非线性系统,本文提出了间接自适应神经网络控制器的设计方案,并基于系统函数界函数的单调递增性质,提出了变量分离方法,同时利用间接自适应神经网络控制技术和Backstepping(反推)相结合的方法,构造出间接自适应神经网络状态反馈控制器,所构造的间接自适应控制器,保证了闭环系统的所有信号是半全局有界的,并且系统的所有状态收敛到原点充分小的邻域内,有效地解决了一类非线性非严格反馈系统的自适应神经网络控制问题,并采用数值例子进行仿真实验。仿真结果表明,在本文所提出的控制律的作用下,不但保证了闭环系统的稳定,而且保证所有信号在闭环系统有界。该控制器为一类非严格反馈非线性系统的稳定性控制提供了理论参考。     

非匹配不确定非线性系统的反演变结构控制

讨论一类非匹配不确定的非线性系统的输出跟踪问题。结合反演(Backstepping)设计方法和变结构控制，提出了反演变结构控制策略。对存在非匹配不确定性和未知干扰的系统，设计的反演变结构控制器实现鲁棒输出跟踪，闭环系统在有限时间进入滑动模态。仿真算例证实理论结果。     

Terminal Angular Constraint Integrated Guidance and Control for Flexible Hypersonic Vehicle with Dead-Zone Input Nonlinearity

This paper presents an integrated guidance and control model for a flexible hypersonic vehicle with terminal angular constraints. The integrated guidance and control model is bounded and the dead-zone input nonlinearity is considered in the system dynamics. The line of sight angle, line of sight angle rate, attack angle and pitch rate are involved in the integrated guidance and control system. The controller is designed with a backstepping method, in which a first order filter is employed to avoid the differential explosion. The full tuned radial basis function(RBF) neural network(NN) is used to approximate the system dynamics with robust item coping with the reconstruction errors, the exactitude model requirement is reduced in the controller design. In the last step of backstepping method design, the adaptive control with Nussbaum function is used for the unknown dynamics with a time-varying control gain function. The uniform ultimate boundedness stability of the control system is proved. The simulation results validate the effectiveness of the controller design.     

一种智能反步控制方法及其应用

针对反作用射流导弹的非线性和参数不确定性严重的特点,提出一种鲁棒自适应反步智能控制(Backstepping)方法。通过非特定的Lyapunov函数,采用遗传算法优化Backstepping镇定系数,得到适当的函数降低了当镇定系数不当时跟踪误差对控制律的影响。结合模糊小脑模型(FC-MAC)神经网络,推出系统参数不确定时的鲁棒控制律,克服了传统自适应反步法对模型不确定性要求线性有界问题。仿真结果表明,这种结合Lyapunov函数选择和参数优化的Backstepping方法鲁棒性强,受参数变化影响小。     

Sliding-mode control of path following for underactuated ships based on high gain observer

A nonlinear robust control strategy is proposed to force an underactuated surface ship to follow a predefined path with uncertain environmental disturbance and parameters.In the controller design,a high-gain observer is used to estimate velocities,thus only position and yaw angle measurements are required.The control problem of underactuated system is transformed into a control of fully actuated system through adopting an improved line-of-sight(LOS) guidance law.A sliding-mode controller is designed to eliminate the yaw angle error,and provide the control system robustness.The control law is proved semi-globally exponentially stable(SGES) by applying Lyapunov stability theory,and numerical simulation using real data of a monohull ship illustrates the effectiveness and robustness of the proposed methodology.     

基于模糊干扰观测器的抗饱和自适应反步控制

针对一类输入受限的非匹配不确定非线性系统,提出了一种抗饱和自适应反步控制方法.利用模糊干扰观测器在线逼近系统的未知非匹配不确定及干扰,采用反步控制方法设计自适应控制器.控制系统设计中引入限幅滤波器,有效降低了控制输入饱和对系统稳定性的影响,并且控制器设计无需对虚拟控制律进行重复求导.利用李亚普诺夫稳定性定理,证明了闭环系统渐近稳定.仿真结果表明了该方法的有效性.     

考虑输入饱和的高超声速飞行器反步法控制

为解决输入饱和、参数不确定和气动弹性影响下的高超声速飞行器控制问题,提出一种基于反步法的非线性鲁棒自适应控制方法.针对高超声速飞行器纵向通道控制问题,将其分解为速度子系统和高度子系统分别进行控制器设计.首先,基于Lyapunov稳定原理设计了参数估计自适应律来处理输入受限情况的速度跟踪控制问题,即使出现推力饱和也能保证系统稳定性;然后,采用自适应反步法对高度子系统进行分层递推设计,通过引入自适应律对不确定参数进行在线实时估计,以提高控制器的鲁棒性,并且实现了高度的稳定跟踪;同时利用微分跟踪器来获取虚拟控制指令导数;采用鸭翼与升降舵联动控制策略,通过选取合适的联动控制增益可以同时消除控制面与升力耦合带来的非最小相位特性和控制输入对一阶弹性模态的激励;最后,基于LaSalle不变集原理证明了闭环控制系统的稳定性.仿真结果表明,所设计的控制器能够有效处理弹性高超声速飞行器的气动参数不确定和控制饱和问题,并且具有良好的闭环跟踪性能.     

模型不确定非线性系统的自适应模糊Backstepping预测控制

为解决一类模型不确定严格反馈非线性系统的跟踪控制问题,提出一种使闭环系统稳定且滚动时域性能指标在线最小化的自适应模糊反步预测控制策略。模糊系统用来逼近该设计过程中的未知非线性项,自适应参数直接用来估计最优逼近权值向量范数的平方,从而只有一个自适应参数需要在线调节;同时考虑模糊基函数的性质,所设计的控制律与自适应律均不含模糊基函数项,理论证明该方法设计的控制器保证闭环系统所有信号是半全局有界的,并且跟踪误差收敛于零的某一邻域。该方法所设计的控制器形式简单,计算量小,更易于实际应用,仿真算例验证提出算法的有效性。