非完整控制系统的理论与应用

本文综述了近年来在非完整控制系统（即带有不可积约束条件的控制系统）理论与应用方面的研究进展．总结了有关非完整控制系统的镇定、控制及规划等方面的主要成果与方法；并介绍了有关的应用；最后提出了若干待研究的问题．

动态非完整控制系统的指数镇定及其在一类车式机器人中的应用

本文研究了用动力学方程表示的双输入链式非完整系统的镇定问题，设计出了非连续的指数镇定律，并将其用于一类移动机器人的位姿镇定中．仿真结果表明了该控制律的有效性．

受非完整约束移动机器人的跟踪控制

讨论受非完整约束移动机器人运动学模型和动力学模型的跟踪控制问题.通过把它们化成统一的标准型,提出了新的动态跟踪控制器.这些控制器具有维数低和没有奇异点的优点.

不确定非完整动力学系统的指数镇定

研究具有未知惯性参数非完整动力学系统的镇定问题，基于非连续变换和动力学方程的性质，设计出两类非连续指数镇定律——鲁棒控制律和自适应控制律。将其用于一类移动机器人的位姿镇定，仿真结果验证了所提出控制方法的有效性。

用滑动模态实现一类非完整动力学系统的指数镇定

对于基变量具有对称性的一类确定非完整动力学系统 ,直接基于该系统模型 ,利用滑动模态的方法设计了指数镇定控制器 ,得到了状态空间中的一个区域 .当系统初始状态位于该区域内时 ,系统状态是指数收敛的 ,而当初始状态不在该区域内时 ,可用非零的开环常值控制使系统状态在有限时间内进入这一区域 .因此 ,它是一种简洁的全局镇定律 .最后 。

一类不确定非完整动力学系统的时变镇定

对于一类具有未知惯性参数的非完整动力学系统，提出了新的时变自适应镇定律，将其用于一类移动机器人的位姿镇定中．仿真结果验证了所提控制方法的有效性．

终端滑模的(1,2)型非完整机器人有限时间镇定

针对(1,2)型非完整轮式移动机器人动态反馈模型,通过状态-输入变换得到相应链式系统,运用终端滑模控制技术和切换控制策略,给出了一个不连续的有限时间状态反馈控制器,并根据有限时间稳定性理论证明了相应闭环系统的原点平衡点是全局有限时间稳定的,改善了现有方法渐近稳定的收敛时耗过长的设计缺点。最后,数值仿真验证了控制方法的有效性。

实际输入饱和的一类非完整运动学系统的镇定

对一类非完整移动机器人提出了实际输入饱和下镇定控制器的设计方案.这种设计不是基于链式系统而是基于原始系统的.控制器的设计使用了滑模控制和多步控制策略,并用Lyapunov的思想证明了闭环系统的收敛性.最后,用设计的控制器对一类机器人进行了仿真,验证了方法的有效性.

基于道路势场的智能车辆机动驾驶控制算法

受机器人基于人工势场的路径控制方法的启发,在文献[3]的基础上,提出了车辆机动行驶控制机制。首先,定义了基于停车视距的车辆机动行驶动态目标位置;其次,依据人工势场建模原理构建道路势场;为了平滑车辆行驶路线,采用了贝塞尔(Bezier)曲线车辆轨迹拟合的方法;最后,针对车辆系统是典型的非完整控制系统,将车辆运动学模型转换为链式系统模型,实现相对简化系统控制设计,增强系统实时性的目的。仿真控制实验说明这种方法对车辆的机动控制具有较好的轨迹跟踪效果和全局稳定性。

基于轨迹规划的自由漂浮空间机器人抓取运动物体的研究

针对空间机器人非完整性和冗余性 ,对笛卡尔空间下的轨迹规划问题进行了研究。在此基础上 ,分析了空间机器人抓取运动物体的策略 ,提出了基于轨迹规划的空间机器人路径规划方法 ,并以三自由度空间机器人为例 ,对空间机器人抓取运动目标体的问题进行了研究 ,该方法是开环控制方法 ,但由于在进行轨迹跟踪过程中 ,误差不累积 ,得到的实际曲线与理论曲线相近 。

Stabilization of discrete nonholonomic chained system

Aimed at the stabilization of the nonholonomic chained system under fixed sample control, two control laws were proposed. The discrete model of the nonholonomic chained system under zero-hold was obtained through the integrate method to the continuous model. And the discrete model was transformed to the form with two linear subsystems through coordinate transformation. Two feedback control laws, time-invariant control law and time-varying control law, were proposed; and the local stabilization and global stabilization were realized respectively. The simulation results show the effectiveness of the proposed control laws. The discrete nonholonomic chained system can converge to zero from any initial state exponentially, and the convergence rate can be changed through changing the parameters of the control laws.

Symmetries and Mei Conserved Quantities of Nonholonomic Controllable Mechanical Systems

This paper concentrates on studying the symmetries and a new type of conserved quantities called Mei conserved quantity. The criterions of the Mei symmetry, the Noether symmetry and the Lie symmetry are given. The conditions and the forms of the Mei conserved quantities deduced from these three symmetries are obtained. An example is given to illustrate the application of the result.

Adaptive output feedback control for uncertain nonholonomic chained systems

An adaptive output feedback control was proposed to deal with a class of nonholonomic systems in chained form with strong nonlinear disturbances and drift terms. The objective was to design adaptive nonlinear output feedback laws such that the closed-loop systems were globally asymptotically stable, while the estimated parameters remained bounded. The proposed systematic strategy combined input-state-scaling with backstepping technique. The adaptive output feedback controller was designed for a general case of uncertain chained system. Furthermore, one special case was considered. Simulation results demonstrate the effectiveness of the proposed controllers.

Finite Time Consensus Problem for Multiple Non-Holonomic Agents with Communication Delay

In this paper, finite time consensus problem is discussed for multiple non-holonomic mobile agents with constant communication delay. The objective is to design non-smooth distributed control laws such that multiple non-holonomic mobile agents can be all in agreement within any given finite time larger than communication delay. The authors propose a novel switching control strategy with the help of Lyapunov-based method and graph theory.

Integrated adaptive dynamic surface car-following control for nonholonomic autonomous electric vehicles

In this paper,the car-following control problem of nonholonomic autonomous electric vehicles in the curved highway is studied.Owing to the fact that the nonholonomic autonomous electric vehicles have the features of strong coupling,parametric uncertainties,nonlinearities and external disturbances,a novel integrated adaptive car-following control system is constructed to supervise the longitudinal and lateral motions of vehicles.Firstly,an adaptive fuzzy dynamic surface car-following control strategy is presented to determine a vector of total forces and torque of autonomous electric vehicles,which can guarantee the uniform ultimate boundedness of close-loop control signals.Then,an optimal tire forces distribution law is proposed to dynamically allocate the desired coupled tire longitudinal and lateral forces in real-time.Finally,simulation results illustrate the effectiveness and robustness of the proposed car-following control approach.

The Exponential Stabilization of Uncertain Chained Form Systems of Mobile Robots Based on Visual Servoing

A system for a type of nonholonomic wheeled mobile robots equipped with an uncalibrated camera fixed to the ceiling is investigated.Based on the visual feedback and the state-input transformation,models of uncertain chained form systems are presented for the robot-camera systems.Then,new smooth time-varying feedback controllers are proposed to exponentially stabilize the uncertain chained system by using state-scaling and control theories for two cases.The exponential stabilities of the closed-loop uncertain systems are rigorously proved.Simulation results demonstrate the effectiveness of the proposed strategies.

OUTPUT-FEEDBACK CONTROL FOR NONHOLONOMIC SYSTEMS WITH LINEAR GROWTH CONDITION

This paper deals with the stabilization of the nonholonomic systems with strongly nonlinear uncertainties. The objective is to design an output feedback law such that the closed-loop system is globally asymptotically regulated at the origin. The systematic strategy combines the input-state scaling technique with the backstepping technique. A novel switching control strategy based on the output measurement of the first subsystem is employed to make the subsystem far away from the origin. The simulation demonstrates the effectiveness of the proposed controller.