硕士学位论文基于梯度恢复算法的航天器基于梯度恢复算法的航天器基于梯度恢复算法的航天器基于梯度恢复算法的航天器追逃策追逃策追逃策追逃策略略略略研究研究研究研究RESEARCHRESEARCHRESEARCHRESEARCHOFOFOFOFSEQUENTIALSEQUENTIALSEQUENTIALSEQUENTIALGRADIENTGRADIENTGRADIENTGRADIENTRESTORATIONRESTORATIONRESTORATIONRESTORATIONAAAALGORITHMLGORITHMLGORITHMLGORITHMANDANDANDANDITSITSITSITSAPPLI-APPLI-APPLI-APPLI--CATION-CATION-CATION-CATIONININININPURSUIT-EVASIONPURSUIT-EVASIONPURSUIT-EVASIONPURSUIT-EVASIONGAMESGAMESGAMESGAMES姚志虎哈尔滨工业大学2020202012121212年7777月国内图书分类号:V412.4+1学校代码:10213国际图书分类号:533密级:公开工学硕士学位论文基于梯度恢复算法的航天器追逃基于梯度恢复算法的航天器追逃基于梯度恢复算法的航天器追逃基于梯度恢复算法的航天器追逃策略研究策略研究策略研究策略研究硕士研究生:姚志虎导师:张秋华教授申请学位:工学硕士学科:固体力学所在单位:航天学院答辩日期:2012年7月授予学位单位:哈尔滨工业大学ClassifiedIndex:V412.4+1U.D.C:533DissertationfortheMasterDegreeinEngineeringRESEARCHRESEARCHRESEARCHRESEARCHOFOFOFOFSSSSEQUENTIALEQUENTIALEQUENTIALEQUENTIALGGGGRADIENTRADIENTRADIENTRADIENTRRRRESTORATIONESTORATIONESTORATIONESTORATIONALGORITHMALGORITHMALGORITHMALGORITHMANDANDANDANDITSITSITSITSAPPLI-APPLI-APPLI-APPLI--CATION-CATION-CATION-CATIONININININPURSUIT-EVASIONPURSUIT-EVASIONPURSUIT-EVASIONPURSUIT-EVASIONGAMESGAMESGAMESGAMESCandidateCandidateCandidateCandidate::::YaozhihuSupervisorSupervisorSupervisorSupervisor::::Prof.ZhangQiuhuaAcademicAcademicAcademicAcademicDegreeDegreeDegreeDegreeAppliedAppliedAppliedAppliedforforforfor::::MasterofEngineeringSpecialitySpecialitySpecialitySpeciality::::SolidMechanicsAffiliationAffiliationAffiliationAffiliation::::SchoolofAstronauticsDateDateDateDateofofofofDefenceDefenceDefenceDefence::::July,2012Degree-Conferring-InstitutionDegree-Conferring-InstitutionDegree-Conferring-InstitutionDegree-Conferring-Institution::::HarbinInstituteofTechnology摘要I摘要本文的主要研究内容是梯度恢复算法及其在基于微分对策的两航天器追逃策略问题中的应用,并通过matlab软件对圆与椭圆参考轨道上的两航天器追逃最优策略问题进行仿真计算与分析。两航天器的追逃微分对策是典型的双边最优控制问题。这类问题一般计算量大,求解过程复杂。而基于求解单边最优问题的梯度恢复算法简单有效且适应性强。因此,为了能尝试用梯度恢复算法解决该类问题,在建立两航天器追逃对策模型时,本文应用双边控制转化为单边控制的等价转化方法。梯度恢复算法是米勒(A.Miele)等人为解决复杂模型的最优控制问题而提出的一种数值算法。该算法的主要思想是:通过不断地减小最优条件误差以及约束误差,最终得到满足要求的解。其中每一循环的过程分两步:梯度阶段,使指标函数尽量地接近最优值,同时控制约束误差的上限;恢复阶段,在不影响指标函数接近最优的前提下,使约束误差罚函数减小到零,之后,通过梯度恢复的不断循环,使最优控制误差罚函数接近到零,即得最优解。该算法适用于一阶微分方程约束之下的最优问题,并具有较好的收敛性。该算法的特点是:将梯度相与恢复相结合在同一迭代过程之内,使性能指标泛函和约束条件误差都保持逐渐下降,并且不致引起过大的变化。方法格式简单统一,便于实现,对于不同的最佳控制问题,代入不同的性能指标即可实现。本文以Matlab软件为工具,用梯度恢复算法分别计算了以距离为支付圆参考轨道的高轨道、低轨道算例和椭圆参考轨道的高轨道算例。得出,对于航天器追逃问题,本文所采用的先将双边控制转化为等价的单边控制形式再利用梯度恢复算法求解的过程是一个可行的方法,数值算法也具有较好的收敛性。关键词:航天器追逃;梯度恢复算法;微分对策;最优控制摘要IIAbstractAbstractAbstractAbstractThispaperstudiesthesequenceofgradientrecoveryalgorithm(SGRA)anditsapplicationinpursuit-evasiondifferentialgameanalysisoftwospacecraftsandthendosimulationanalysisonthepursuitoftwospacecraftinthecircularandellipticreferenceorbitinmatlabsoftware.Thispaperbrieflydescribesthedifferentialgameconceptsandmathematicaltheory,researchandanumericalmethodtosolvesuchproblems-theSequentialGradientRestorationAlgorithm.Thenwegivetheequivalentconversionmethodforthebilateralcontrolintounilateralcontrol,solvingtheproblemforlineartwo-pointboundaryvaluedifferentialequationswithparticularsolutionmethod.Thesequenceofgradientrecoveryalgorithmappliesontheoptimalcontrolproblemforfirstorderdifferentialequations.Whensolvingtheproblemofoptimalcontrol,theprocesscanbemadeintotwosteps,thegradientphaseandrestorationphase.Duringthecalculation,thegradientphaseisintendedtocontrolthevolumefortheoptimalstatequantityandoptimalcontrolequations,theobjectivefunctionalongtheoptimaldirectionisguaranteedduringthecorrection,whiletherestorationphaseisintendedtoreducetheerrorofconstraintequationswithinacertainrangewhichissufficientlysmall.Afterrepeatedanditerativeseveraltimesonecangetareasonableresult.Thesequenceofgradientrecoveryalgorithmisawidelyusedalgorithminoptimalcontrolproblems.Thispaperusesgradientrecoveryalgorithmtocalculatethepaymentofacircularreferenceorbittothedistancehighandloworbitoperatorcasesandellipticalreferenceorbittrackexample.Weconcludethat,forsolvingtheoptimalflightpathofthespacecraft,thegradientrecoveryalgorithmisamoreaccuratealgorithmandhasgoodconvergence.Keywords:Keywords:Keywords:Keywords:spacecrafts,Pursuit-evasiondifferentialgame,sequentialgradientrestorationalgorithm(SGRA),optimalcontrol哈尔滨工业大学工学硕士学位论文III目录摘要.................................................................................................................................IAbstractAbstractAbstractAbstract...........................................................................................................................II第1章绪论...................................................................................................................11.1课题背景..................................................................................................................11.2国内外综述..............................................................................................................21.3研究内容..................................................................................................................41.4本章小结..................................................................................................