欠驱动水下航行器三维直线航迹跟踪控制

针对欠驱动水下航行器的三维直线航迹跟踪控制问题,基于虚拟向导建立了三维航迹跟踪误差模型,采用反馈增益反步法设计航迹跟踪控制器,通过合理选择控制器参数消除了部分非线性项,与传统反步法设计相比简化了虚拟控制量的形式,并且能够避免基于视线法设计导引律时存在固有奇异值点的问题.基于李雅普诺夫稳定性理论分析了闭环跟踪误差系统的渐近稳定性.最后将设计的控制器应用于欠驱动水下航行器进行仿真实验,结果表明控制器具有精确的三维航迹的跟踪能力,并对外界干扰和模型参数不确定性具有较好的鲁棒性.     

基于反步法的欠驱动UUV的3维路径跟踪控制

研究了欠驱动无人水下航行器(unmanned underwater vehicle,UUV)在3维空间中的路径跟踪控制器设计及其稳定性分析问题.首先建立2阶积分器形式的欠驱动UUV空间6自由度运动模型和动力学模型.针对该运动模型,以位置误差作为虚拟控制变量,基于反步法(backstepping)设计路径跟踪控制器.根据李亚普诺夫理论,在理论上证明了所设计的路径跟踪控制系统是稳定的.该控制器实现了欠驱动UUV 3维空间的路径跟踪控制.仿真结果验证了控制器的有效性.     

基于反馈增益反步法欠驱动无人水下航行器三维路径跟踪控制

针对欠驱动无人水下航行器的三维空间路径跟踪控制问题.基于虚拟向导建立载体坐标系下的三维路径跟踪运动学误差模型,首先设计跟踪误差反馈增益形式的线性控制项镇定位置跟踪系统,避免计算虚拟控制量导数的复杂形式;然后基于反步法设计动力学控制器,通过合理的选择控制器参数消除了部分非线性项,简化了虚拟控制量的形式,同时避免了采用传统反步法设计控制器时存在的奇异值问题,基于李雅普诺夫稳定性理论设计鲁棒反馈补偿项,保证了闭环跟踪误差系统状态的一致最终有界.仿真实验表明本文设计控制器能够精确跟踪三维曲线路径,并对外界干扰具有较好的鲁棒性.     

基于高度计信息处理的欠驱动无人水下航行器地形跟踪控制

针对高度测量信息不准确情况下的欠驱动无人水下航行器(UUV)地形跟踪控制问题,结合欠驱动UUV的固有特性,提出了一种基于反步法的非线性海底地形跟踪控制方法。首先,针对高度计受海水温度和盐度等海洋环境的干扰而导致高度测量信息不准确的问题,采用卡尔曼滤波器对高度测量信息进行处理,提高高度信息的准确性;然后,基于Lyapunov稳定性理论和反步法设计了非线性地形跟踪控制器,并证明了控制系统的渐近稳定性;最后,分别通过仿真实验和海试实验对所提出的方法进行验证。结果表明,基于高度信息滤波处理的欠驱动UUV非线性地形跟踪控制器能够实现精确的地形跟踪控制。     

基于高度计信息处理的欠驱动无人水下航行器地形跟踪控制

针对高度测量信息不准确情况下的欠驱动无人水下航行器(UUV)地形跟踪控制问题,结合欠驱动UUV的固有特性,提出了一种基于反步法的非线性海底地形跟踪控制方法。首先,针对高度计受海水温度和盐度等海洋环境的干扰而导致高度测量信息不准确的问题,采用卡尔曼滤波器对高度测量信息进行处理,提高高度信息的准确性;然后,基于Lyapunov稳定性理论和反步法设计了非线性地形跟踪控制器,并证明了控制系统的渐近稳定性;最后,分别通过仿真实验和海试实验对所提出的方法进行验证。结果表明,基于高度信息滤波处理的欠驱动UUV非线性地形跟踪控制器能够实现精确的地形跟踪控制。     

基于非线性迭代滑模的欠驱动UUV三维航迹跟踪控制

为实现欠驱动无人水下航行器(Unmanned underwater vehicle, UUV)在未知海流干扰作用下的三维航迹跟踪控制, 提出一种基于工程解耦思想设计的非线性迭代滑模航迹跟踪控制器. 基于虚拟向导的方法,建立UUV空间航迹跟踪误差方程;采用迭代方法设计非线性滑模控制器, 无需对UUV模型参数不确定部分和海流干扰进行估计,避免了舵的抖振现象以及减小了稳态误差与超调问题. 仿真实验表明,设计的控制器对欠驱动UUV系统的模型参数摄动及海流干扰变化不敏感、 且设计参数易于调节,可以实现三维航迹的精确跟踪.     

面向动目标围捕的Multi-UUV编队协调控制研究

针对动目标围捕过程对Multi-UUV编队结构的灵活性要求较高的问题,基于欠驱动UUV的数学模型,在目标轨迹能够准确预测的前提下,改进了协调编队运动控制器。协调编队运动控制器的控制目标是在Multi-UUV编队跟踪并围捕动目标过程中,避免Multi-UUV之间,UUV与障碍物以及UUV与动目标之间的碰撞并以稳定的编队结构围捕动目标。将控制器设计过程分解为运动学控制和动力学控制。在运动学控制部分,实现动目标跟踪、UUV之间避撞及UUV偏航角误差为零的控制目标。在动力学控制部分,应用反步法设计实际的控制输入。仿真案例验证了协调运动控制器在动目标围捕中的有效性。     

欠驱动飞艇三维路径跟踪控制

针对欠驱动飞艇的路径跟踪控制问题,提出了一种基于制导向量场的三维路径跟踪控制方法.首先,引入向量场理论.接着基于牛顿–欧拉方程建立欠驱动飞艇动力学模型.基于所提模型和向量场理论构造制导向量场以获得期望姿态角和期望速度.然后结合反步法和PD控制设计路径跟踪控制器,用指令滤波器对控制器设计过程中虚拟控制的导数进行估计,避免了复杂的解析计算.所设计的控制器是由制导向量场子系统、姿态稳定环和速度跟踪环组成的内外环结构.稳定性分析证明了飞艇的路径跟踪误差最终一致有界.最后仿真结果验证了所提出方法的有效性.     

基于滤波反步法的欠驱动AUV三维路径跟踪控制

研究了欠驱动自主水下航行器 (Autonomous underwater vehicle, AUV)的三维空间路径跟踪控制问题.针对基于虚拟向导建立的三维路径跟踪误差模型, 采用滤波反步法设计跟踪控制器,通过二阶滤波过程获得虚拟控制量的导数, 避免了直接对虚拟控制量解析求导的复杂过程, 同时滤除了高频测量噪声, 增加了系统对噪声的鲁棒性.通过设计滤波误差补偿回路, 保证了滤波信号对虚拟控制量的逼近精度.基于李雅普诺夫稳定性理论设计鲁棒项, 保证了闭环跟踪误差系统状态的渐近稳定.仿真结果表明了该控制器对噪声干扰具有一定的鲁棒性, 能够实现对三维路径的精确跟踪.     

欠驱动UUV的空间直线路径跟踪控制

针对欠驱动无人水下航行器(UUV)设计了基于视距导航法的路径跟踪控制方法。采用视距导航法建立欠驱动UUV的路径跟踪误差模型将位置误差控制转换为航速控制、艏向角控制和纵倾角控制,使得路径跟踪问题的输出空间从6个自由度降为3个自由度。对简化的3个自由度设计控制器,并证明了控制器的稳定性。最后以空间平行于x轴的直线为参考路径进行了路径跟踪控制仿真,验证了该方法的有效性。     

Robust fuzzy 3D path following for autonomous underwater vehicle subject to uncertainties

This paper addresses a three-dimensional (3D) path following control problem for underactuated autonomous underwater vehicle (AUV) subject to both internal and external uncertainties. A two-layered framework synthesizing the 3D guidance law and heuristic fuzzy control is proposed to achieve robust adaptive following along a predefined path. In the first layer, a 3D guidance controller for underactuated AUV is presented to guarantee the stability of path following in the kinematics stage. In the second layer, a heuristic adaptive fuzzy algorithm based on the guidance command and feedback linearization Proportional-Integral-Derivative (PID) controller is developed in the dynamics stage to account for the nonlinear dynamics and system uncertainties, including inaccuracy modelling parameters and time-varying environmental disturbances. Furthermore, the sensitivity analysis of the heuristic fuzzy controller is presented. Against most existing methods for 3D path following, the proposed robust fuzzy control scheme reduces the design and implementation costs of complicated dynamics controller, and relaxes the knowledge of the accuracy dynamics modelling and environmental disturbances. Finally, numerical simulation results validate the effectiveness of the proposed control framework and illustrate the outperformance of the proposed controller as well.     

遗传优化的欠驱动船舶镇定控制

针对带有加速度非完整约束的三自由度欠驱动水面船舶镇定问题,提出了一种基于微分同胚等效变换和Lyapunov直接法的后推镇定控制算法,同时为了解决因系统输入固有饱和特性而导致控制不稳定问题,提出了基于遗传优化的欠驱动水面船舶镇定控制改进算法。并对风浪干扰进行了Lyapunov补偿,保证了控制器对外界干扰的鲁棒性。仿真实验表明了该算法的有效性,并且优化后的控制器有效地防止了因控制能量过大导致的系统不稳问题。     

基于离散滑模预测的欠驱动AUV三维航迹跟踪控制

针对欠驱动自主水下航行器（AUV）的模型不确定和外界海流干扰问题,为了实现欠驱动AUV的三维航迹跟踪控制,采用虚拟向导法建立空间运动误差离散化模型.基于递归滑模思想设计离散滑模预测控制器,利用滚动优化和反馈校正方法补偿了不确定项对滑模预测模型的影响.最后针对某欠驱动AUV进行了空间曲线跟踪控制仿真实验.结果表明,所设计的控制器可以较好地克服时变非线性水动力阻尼对系统的影响,并对外界海流干扰有较好的抑制作用,保证了欠驱动AUV三维航迹跟踪系统的鲁棒性,实现了三维航迹的精确跟踪.     

自主水下航行器的变质心跟踪控制

The trajectory-tracking control problem is investigated for an autonomous underwater vehicle (AUV) moving in the vertical plane using an internal point mass and a rear thruster as actuators. Combined with the dynamics of the point mass, the AUV is modeled as an underactuated system. A Lyapunov-based tracking controller is proposed by using backstepping approach to stabilize the error dynamics and force the position errors to a small neighborhood of the origin. Simulation results validate the proposed tracking approach.     

Trajectory Tracking Control for a Rotary Wing Vehicle Powered by Four Rotors

The present paper presents a trajectory tracking control scheme for an underactuated rotary wing vehicle. The translational controller is designed based on feedback linearization and saturated control. The rotational controller is designed based on the passivity properties of the rotational dynamics. The interconnection between the translational and the rotational controllers is inspired by the backstepping control technique. The final control structure allows to include an integral action that is able to compensate constant disturbances on the rotational dynamics. It is shown that the resulting closed–loop dynamics has a local asymptotic stability property. Numerical simulations show the performance of the proposed controller.     

Finite‐time geometric control for underactuated aerial manipulators with unknown disturbances

In this article, the finite‐time geometric control for underactuated aerial manipulators is investigated. The dynamics of the aerial manipulator with unknown disturbances is analyzed first. The dynamics of the system is decomposed into the locked subsystem and shape subsystem. The finite‐time controller for the aerial manipulator is then designed based on the analyzed dynamics. In the controller, the attitude tracking error of the aircraft base is expressed from the rotation matrix, which makes the controller continuous and almost globally stable on SO(3). A continuous adaptive term is added in the controller to compensate for the unknown disturbances. Finite‐time filters are designed to ensure the smoothness of the commands on each loop. The convergence of the entire controlled system is strictly proved using Lyapunov theory and the definition of finite‐time stability. The results show that the tracking error and the disturbance bound estimation error of the entire system are finite‐time bounded near origin. Finally, comparative simulation results are presented to show the performance of the proposed controller.     

一类非线性欠驱动移动系统的加速度反馈增强的H∞扰支抑制控制

In this paper, a generalized acceleration feedback control (AFC) design method, named AFC enhanced H∞ controller, is proposed for both fnllactuated and underactuated nonlinear autonomous vehicle systems. The AFC is designed as a robust enhancement to the normal control based on known dynamics. First, in order to reject the uncertainties and external disturbances, a linear prefilter is used in the new AFC design method to replace the high gain in the normal AFC. Then, backstepping algorithm is applied to the AFC design of underactuated systems. The analysis of both the disturbance attenuation in frequency domain and input-output finite gain L2 stability shows the new controller design method is applicable. In the end, simulations are conducted with respect to the tracking control of unmanned model helicopter. The results are compared with those obtained by the tracking control without AFC to verify the feasibility of the new method.     

Dynamic modeling and nonlinear tracking control of a novel modified quadrotor

In this article, a nonlinear tracking controller is designed based on Lyapunov stability for a novel aerial robot. The proposed 6‐rotor configuration improves stability and payload lifting capacity of the robot compared with conventional quadrotors while avoiding further complexities in the robot dynamics and steering principles. The dynamical model of the robot is derived using Newton‐Euler method. The model represents a nonlinear, coupled, and underactuated system. The proposed control strategy includes 2 main parts: an attitude controller and a position controller. Both the attitude and position controls are Lyapunov‐based nonlinear tracking controllers that guarantee the asymptotic convergence of the states' tracking errors to zero. Simulation results are presented to illustrate appropriate performance of the closed‐loop system in terms of position/attitude tracking even in the presence of wind disturbance.     

Control‐oriented modeling and deployment of tensegrity–membrane systems

This study addresses control‐oriented modeling and control design of tensegrity–membrane systems. Lagrange's method is used to develop a control‐oriented model for a generic system. The equations of motion are expressed as a set of differential‐algebraic equations (DAEs). For control design, the DAEs are converted into second‐order ordinary differential equations (ODEs) based on coordinate partitioning and coordinate mapping. Because the number of inputs is less than the number of state variables, the system belongs to the class of underactuated nonlinear systems. A nonlinear adaptive controller based on the collocated partial feedback linearization (PFL) technique is designed for system deployment. The stability of the closed‐loop system for the actuated coordinates is studied using the Lyapunov stability theory. Because of system complexity, numerical tests are used to conduct stability analysis for the dynamics of the underactuated coordinates, which represents the system's zero dynamics. For the tensegrity–membrane systems studied in this work, analytical proof of zero dynamics stability remains an open theoretical problem. An H_∞ controller is implemented for rapid stabilization of the system at the final deployed configuration. Simulations are conducted to test the performance of the two controllers. The simulation results are presented and discussed in detail. Copyright © 2016 John Wiley & Sons, Ltd.