冯文莉 张东凯 王朝立 杜庆辉
摘要
随着随机非线性控制的发展,随机非完整系统的控制引起了学者们的注意.本文首先探讨了随机非完整控制系统的镇定问题,涉及严反馈链式系统的反馈镇定和不满足严反馈的移动机器人镇定等;其次,介绍了该系统跟踪控制及现状;最后,在总结现有结果的基础上,分析了随机非完整系统发展的趋势,给出了6个可能的研究方向.关键词
随机非完整系统;镇定;跟踪
中图分类号TP2732
文献标志码A
0引言
非完整系统控制问题的研究已有30余年的历史,它的主要难点在于不存在连续的时不变纯状态反馈镇定器[1],故需要新的控制和稳定性理论设计控制器.基于文献[1]的结论,Kolmanovsky等[2]给出了非完整系统能够转化为链式系统的结论,文献[3]探讨了非完整系统不连续反馈控制器的设计方法,这些工作为非完整系统的快速发展打下了坚实的基础.
随机控制的概念[4]始于1967年,可是由于随机稳定性理论和方法的匮乏,其控制问题的研究一直是一个难点.基于Backstepping方法,文献[5]首次设计了随机严反馈系统的控制器,它为随机控制的发展,特别是为随机严反馈系统控制的发展打下了坚实的基础,至此许多学者将精力投入到随机控制理论的研究中[68].
近10年来,随机控制理论的发展为非完整系统和随机控制的结合起了极大的推动作用,才有了随机非完整系统控制的可行性,并引起了学者们的注意[913].
1随机非完整系统镇定问题
目前的镇定问题的研究主要为严反馈整链式系统和不满足严反馈随机非完整机器人的镇定,涉及反馈镇定和有限时间镇定等问题.
11状态反馈镇定控制器设计
已有的确定性非完整系统镇定问题的结论,对解决随机非完整系统镇定问题有很大的指导意义.基于Backstepping方法,Ge等[14]设计了带有强非线性项和不确定参数的自适应状态反馈和输出反馈镇定控制器,Hong等[15]探讨了不确定非完整系统的有限时间镇定.
基于视觉伺服模型,文献[16]研究了移动机器人的有限时间镇定问题.基于Backstepping技术,文献[17]设计的自适应状态反馈镇定器能使系统状态以概率全局收敛.基于带有不确定参数的随机非完整系统,文献[1821]给出了自适应律的设计方案.基于文献[22]的结论,Du等[23]讨论了带有非线性参数的高阶非线性系统的自适应镇定反馈控制器,且该系统的第一个方程为随机微分方程.对于带有马尔科夫切换的随机非完整系统,Zhang等[24]和Du等[25]讨论了自适应镇定反馈控制器的设计.文献[2628]设计了随机非完整系统的有限时间镇定器.文献[29]给出了随机非完整变时滞系统的镇定控制器.
12输出反馈镇定控制器设计
文献[3031]设计了非完整链式系统的输出反馈控制律,其主要原因是系统状态只有部分可测.当随机非完整系统的第一个方程为常微分方程时,文献[32]讨论了其输出反馈镇定问题.如果系统满足线性增长条件,文献[33]给出了高增益观测器,设计了输出反馈控制器.Zhang等[34]将文献[33]的结果推广至带有马尔可夫切换的情形,设计了系统的输出反馈镇定控制器.
2随机非完整系统跟踪问题
文献[3540]讨论了非完整系统控制的跟踪问题.基于递归法,文献[4142]讨论了确定性非完整链式系统跟踪问题.由上面的讨论可知,随机非完整系统镇定问题研究的结果较多,但是跟踪问题一直是一个难点,主要的原因在于现存的镇定控制器的设计,需要用到状态变换[41].Zhang等[43]给出了一类随机非完整动力学的模型,设计了自适应跟踪控制器,该控制器能使跟踪误差任意小,最后给出了一个实际的例子.
3机器人镇定控制器的设计
基于文献[44]的模型,Wu等[45]将非完整机器人推广到随机的情形并给出了反馈镇定控制器设计方法,但是此类随机非完整机器人并不满足严格的下三角结构,传统的Backstepping方法很难用于这类系统.在文献[45]讨论的基础上,Shang等[46]和Gao等[47]分别给出了随机非完整机器人的指数状态反馈控制器和鲁棒状态反馈镇定控制器的设计方法.Zhang等[48]将基于视觉伺服的非完整机器人推广到随机的情形,给出了状态反馈镇定控制器的设计方法.Hespanha等[49]将文献[50]中基于不确定参数的非完整移动机器人推广到随机情形,设计的自适应反馈镇定控制器和切换策略能使闭环系统镇定到原点.
4总结与展望
综上所述,10余年来,随机非完整系统发展的较为迅速,涌现了一批结果,主要可分为镇定和跟踪两个方面.但是关于镇定的结果大都为基于不连续变换的运动学系统的控制器设计,而实际系统由于是物理驱动的,多为动力学系统,故还存在下列尚未解决的问题.
41动力学链式系统镇定控制器的设计
基于文献[42,5152]的结果,全部状态可测的满足下三角结构的随机非完整动力学系统可表述为
研究其反馈镇定问题,特别是系统包括不确定该参数和时变系数时自适应控制器的設计和稳定性分析.
3) 将系统(1)—(4)推广到含有马尔科夫切换和任意切换的情形,并讨论控制器的设计.
44有限时间镇定和饱和镇定
参考文献[2628]的结论,研究随机非完整下三角系统、随机前馈系统和随机移动机器人系统的自适应有限时间镇定问题.但是关于此系统饱和镇定问题的研究较少,基于文献[5761]的结论,讨论上述三类系统的饱和镇定问题,包含不确定的情形.
45随机非完整系统的跟踪控制问题
目前只有文献[43]给出了随机非完整系统的跟踪问题,并且第一个子系统还是确定性的,但是对于解决随机非完整系统的跟踪问题有很大的借鉴意义.那么,基于下三角结构和前馈型随机非完整系统的跟踪问题,特别是不确定系统和切换系统的跟踪问题的解决将是下一步工作的重点.
46随机非完整系统新的控制方法
现存的关于随机非完整系统镇定问题的文献大都是基于切换策略的,那么能不能找到新的控制方法解决此问题?
1)基于文献[6264]的结果,利用滑模变结构方法讨论上述三类随机不确定非完整系统的镇定问题,特别是连续滑模理论的应用.
2)结合文献[6567]中光滑时变镇定控制器的设计方法,设计上述三类系统的连续时变反馈控制器.
参考文献
References
[1]Brockett R W.Asymptotic stability and feedback stabilization[C]∥Differential Geometric Control Theory,Boston:Birkhauser,1983:181191
[2]Kolmanovsky I,Mcclamroch N.Developments in nonholonomic control problems[J].IEEE Control Systems,1995,15(6):2036
[3]Astolfi A.Discontinuous control of nonholonomic systems[J].Systems & Control Letters,1996,27(1):3745
[4]Kushner H J.Stochastic stability and control[M].New York:Academic Press,1967
[5]Pan Z G,Baar T.Backstepping controller design for nonlinear stochastic systems under a risksensitive cost criterion[J].SIAM Journal of Control and Optimization,1999,37(3):957995
[6]Deng H,Krstic M.Outputfeedback stochastic nonlinear stabilization[J].IEEE Transactions on Automatic Control,1999,44(2):328333
[7]Wu Z J,Yang J,Shi P.Adaptive tracking for stochastic nonlinear systems with Markovian switching[J].IEEE Transactions on Automatic Control,2010,55(9):21352141
[8]Liu L,Xie X J.State feedback stabilization for stochastic feedforward nonlinear systems with timevarying delay[J].Automatica,2013,49(4):936942
[9]Moshchuk N K,Sinitsyn I N.On stochastic nonholonomic systems[J].Journal of Applied Mathematics and Mechanics,1990,54(2):174182
[10]Shang M,Guo Y X.The meansquare exponential stability and instability of stochastic nonholonomic systems[J].Chinese Physics,2001,10(6):480485
[11]Liu S J,Krstic M.Stochastic source seeking for nonholonomic unicycle[J].Automatica,2010,46(9):14431453
[12]張东凯.随机非完整系统镇定问题研究[D].上海:上海理工大学管理学院,2013
ZHANG Dongkai.The satabilization of stochastic nonholonomic systems[D].Shanghai:Business School,University of Shanghai for Science and Technology,2013
[13]Do K D.Global inverse optimal stabilization of stochastic nonholonomic systems[J].Systems & Control Letters,2015,75:4155
[14]Ge S S,Wang Z,Lee T H.Adaptive stabilization of uncertain nonholonomic systems by state and output feedback[J].Automatica,2003,39(8):14511460
[15]Hong Y G,Wang J K,Xi Z R.Stabilization of uncertain chained form systems within finite settling time[J].IEEE Transactions on Automatic Control,2005,50(9):13791384
[16]Chen H,Ding S R,Chen X,et al.Global finitetime stabilization for nonholonomic mobile robots based on visual servoing[J].International Journal of Advanced Robotic Systems,2014,11:113
[17]Wang J,Gao H Q,Li H Y.Adaptive robust control of nonholonomic systems with stochastic disturbances[J].Science in China Series F(Information Sciences),2006,49(2):189207
[18]Zhang D K,Wang C L,Chen H,et al.Adaptive stabilization of stochastic nonholonomic systems with nonhomogeneous uncertainties[J].Transactions of the Institute of Measurement and Control,2013,35(5):648663
[19]Wang C L,Wei G L,Zhang H J.Adaptive stabilization of stochastic nonholonomic systems with uncertain parameters and timevarying coefficients[C]∥IFAC Proceedings Volumes,2014,47(3):57345739
[20]Gao F Z,Yuan F S,Yao H J.Adaptive stabilization for a class of stochastic nonholonomic systems with nonlinear parameterization[C]∥24th Chinese Control and Decision Conference,2012,23(1):13771382
[21]Gao F Z,Yuan F S,Wu Y Q.Adaptive stabilization for a class of stochastic nonlinearly parameterized nonholonomic systems with unknown control coefficients[J].Asian Journal of Control,2014,16(6):18291838
[22]Zhao Y,Yu J B,Wu Y Q.Statefeedback stabilization for a class of more general high order stochastic nonholonomic systems[J].International Journal of Adaptive Control and Signal Processing,2011,25(8):687706
[23]Du Q H,Wang C L,Wang G.Adaptive statefeedback stabilization of stochastic highorder nonholonomic systems with nonlinear parameterization[J].Transactions of the Institute of Measurement and Control,2015,37(4):536549
[24]Zhang D K,Wang C L,Qiu J Q.Statefeedback stabilization for stochastic nonholonomic systems with Markovian switching[J].International Journal of Modelling,Identification and Control,2012,16(3):221228
[25]Du Q H,Wang C L,Wang G,et al.Statefeedback stabilization for stochastic highorder nonholonomic systems with Markovian switching[J].Nonlinear Analysis(Hybrid Systems),2015,18:114
[26]Gao F Z,Yuan F S.Finitetime stabilization of stochastic nonholonomic systems and its application to mobile robot[J].Abstract and Applied Analysis,2012(4):118
[27]Gao F Z,Yuan F S,Yao H J.Finitetime stabilization of stochastic nonholonomic systems[C]∥The 31st Chinese Control Conference,2012(4):812817
[28]Gao F Z,Yuan F S,Zhang J,et al.Further result on finitetime stabilization of stochastic nonholonomic systems[J].Abstract and Applied Analysis,2013(5):551552
[29]Gao F Z,Yuan F S,Wu Y Q.Statefeedback stabilisation for stochastic nonholonomic systems with timevarying delays[J].IET Control Theory & Applications,2012,6 (17):25932600
[30]Xi Z R,Feng G,Jiang Z P,et al.Output feedback exponential stabilization of uncertain chained systems[J].Journal of the Franklin Institute,2007,344(1):3657
[31]Zheng X Y,Wu Y Q.Adaptive output feedback stabilization for nonholonomic systems with strong nonlinear drifts[J].Nonlinear Analysis,2009,70(2):904920
[32]Zheng X Y,Wu Y Q.Output feedback stabilization of stochastic nonholonomic systems[C]∥World Congress on Intelligent Control and Automation,2010:20912096
[33]Liu Y L,Wu Y Q.Output feedback control for stochastic nonholonomic systems with growth rate restriction[J].Asian Journal of Control,2011,13(1):177185
[34]Zhang D K,Wang C L,Wei G L,et al.Output feedback stabilization for stochastic nonholonomic systems with nonlinear drifts and Markovian switching[J].Asian Journal of Control,2014,16(6):16791692
[35]Do K D,Jiang Z P,Pan J.Simultaneous tracking and stabilization of mobile robots:an adaptive approach[J].IEEE Transactions on Automatic Control,2004,49(7):11471152
[36]Ma B L,Tso S K.Unified controller for both trajectory tracking and point regulation of secondorder nonholonomic chained systems[J].Robotics and Autonomous Systems,2008,56(4):317323
[37]Tian Y P,Cao K C.An LMI design of tracking controllers for nonholonomic chainedform system[C]∥American Control Conference,2007:45124517
[38]董文杰,霍偉.链式系统的轨迹跟踪控制[J].自动化学报,2000,26(13):310316
DONG Wenjie,HUO Wei.Trajectory tracking control of chained systems[J].Acta Automatica Sinica,2000,26(13):310316
[39]Park B S,Yoo S J,Jin B P,et al.A simple adaptive control approach for trajectory tracking of electrically driven nonholonomic mobile robots[J].IEEE Transactions on Control Systems Technology,2010,18(5):11991206
[40]Li Q X,Hu Y M,Pei H L,et al.Robust output tracking for mobile robot[J].Control Theory and Applications,1998,15(4):515524
[41]Jiang Z p,Nijmeijer H.Tracking control of mobile robots:A case study in backstepping[J].Automatica,1997,33(7):13931399
[42]Jiang Z P,Nijmeijer H.A recursive technique for tracking control of nonholonomic systems in chained form[J].IEEE Transactions on Automatic Control,1999,44(2):265279
[43]Zhang Z C,Wu Y Q.Modeling and adaptive tracking for stochastic nonholonomic constrained mechanical systems[J].Nonlinear Analysis(Modelling and Control),2016,21(2):166184
[44]Astolfi A.Exponential stabilization of a wheeled mobile robot via discontinuous control[J].Journal of Dynamic Systems(Measurement and Control),1999,121(1):121126
[45]Wu Z J,Liu Y H.Stochastic stabilization of nonholonomic mobile robot with headingangledependent disturbance[J].Mathematical Problems in Engineering,2012,DOI:101155/2012/870498
[46]Shang Y L,Meng H.Exponential stabilization of nonholonomic mobile robots subject to stochastic disturbance[J].Journal of Information & Computational Science,2012,9(9):26352642
[47]Gao F Z,Shang Y L.Robust state feedback stabilization for nonholonomic mobile robots with stochastic disturbances[J].International Journal of Applied Mathematics and Statistics,3013,40(10):259268
[48]Zhang D K,Wang C L,Wei G,et al.Statefeedback stabilization for stochastic nonholonomic mobile robots with uncertain visual servoing parameters[J].International Journal of Systems Science,2014,45(7):14511460
[49]Hespanha J,Liberzon D,Morse A S.Towards the supervisory control of uncertain nonholonomic systems[C]∥American Control Conference,1999,5:35203524
[50]Feng W L,Sun Q L,Cao Z J,et al.Adaptive statefeedback stabilization for stochastic nonholonomic mobile robots with unknown parameters[J].Discrete Dynamics in Nature and Society,2013(4):19
[51]Dong W J,Xu Y S,Huo W.On stabilization of uncertain dynamic nonholonomic systems[J].International Journal of Control,2000,73(4):349359
[52]Dong W J,Huo W.Adaptive stabilization of uncertain dynamic nonholonomic systems[J].International Journal of Control,1999,72(18):16891700
[53]Fang Y,Wang C L.Adaptive stabilization for uncertain nonholonomic dynamic mobile robots based on visual serving feedback[J].Acta Automatic Sinica,2011,37(7):857864
[54]Gao F Z,Wu Y Q,Zhang Z C.Finitetime stabilization of uncertain nonholonomic systems in feedforwardlike form by output feedback[J].ISA Transactions,2015,59:125132
[55]Wu Y Q,Gao F Z,Zhang Z C.Saturated finitetime stabilization of uncertain nonholonomic systems in feedforwardlike form and its application[J].Nonlinear Dynamics,2016,84(3):16091622
[56]Gao F Z,Yuan Y,Wu Y Q.Finitetime stabilization for a class of nonholonomic feedforward systems subject to inputs saturation[J].ISA Transactions,2016,64:193201
[57]Gao F Z,Wu Y Q.Finitetime output feedback stabilisation for a class of feedforward nonlinear systems with input saturation[J].International Journal of Systems Science,2017,48(6):12541265
[58]Bloch A,Drakunov S.Stabilization of a nonholonomic system via sliding models[C]∥IEEE Conference of Decision and Control,1995,3:29612963
[59]Jiang Z P,Lefeber E,Nijmeijer H.Saturated stabilization and tracking of a nonholonomic mobile robot[J].Systems & Control Letters,2001,42(5):327332
[60]Wang C L.Semiglobal practical stabilization of nonholonomic wheeled mobile robots with saturated inputs[J].Automatica,2008,44(3):816822
[61]Chen H,Wang C L,Liang Z Y,et al.Robust practical stabilization of nonholonomic mobile robots based on visual servoing feedback with inputs saturation[J].Asian Journal of Control,2014,16(3):692702.
[62]王朝立,霍伟.用滑动模态实现一类非完整动力学系统的指数镇定[J].自动化学报,2000,26(2):254257
WANG Chaoli,HUO Wei.Exponential stabilization of a nonholonomic dynamic system via sliding modes[J].Acta Automatica Sinica,2000,26(2):254257
[63]Hu Y,Ge S S,Su C Y.Stabilization of uncertain nonholonomic systems via timevarying sliding mode control[J].IEEE Transactions on Automatic Control,2004,49(5):757763
[64]Ferrara A,Giacomimi L,Vecchio C.Control of nonholonomic systems with uncertainties via secondorder sliding modes[J].International Journal of Robust and Nonlinear Control,2008,18(4/5):515528
[65]Tian Y P,Li S.Exponential stabilization of nonholonomic dynamic systems by smooth timevarying control[J].Automatica,2002,38(7):11391146
[66]馬保离,霍伟.非完整链式系统的时变光滑指数镇定[J].自动化学报,2003,29(2):301305
MA Baoli,HUO Wei.Smooth timevarying exponential stabilization of nonholonomic chained systems[J].Acta Automatica Sinica,2003,29(2):301305
[67]Samson C.Timevarying feedback stabilization of a carlike wheeled mobile robots[J].International Journal of Robotics Research,1993,12(1):5566