【作者】 侯旭阳；

【导师】 阮晓钢；

【作者基本信息】 北京工业大学 ， 模式识别与智能系统， 2013， 博士

【摘要】 碟形飞行器是一种以内置旋翼为主要动力部件具有碟形外形的飞行器，其能够像直升机一样实现垂直起降和悬停与直升机相比，碟形飞行器因其特殊的内置旋翼结构，在气动效率安全性等方面具有独特优势对碟形飞行器的研究目前仍处在发展阶段，其结构设计气动优化和飞行控制等方面均存在较多的问题，飞行性能尚无法满足实际应用的要求，碟形飞行器的构型飞行控制算法等方面仍需进一步的研究和改进本文设计了具有磁悬浮双旋翼系统和下摆锤结构的新型双旋翼碟形飞行器，建立了飞行器的动力学和运动学模型，并在系统特性分析的基础上，进行了无约束飞行控制以及有约束优化控制的相关研究，取得了以下主要研究成果：1一种磁悬浮双旋翼碟形飞行器系统本文设计了一种磁悬浮双旋翼碟形飞行器系统，其主要的结构特征包括：旋翼末端安装有磁悬浮组件，构成磁悬浮旋翼，能够实现旋翼桨叶末端的轴向定位；上下置式的两个磁悬浮旋翼安置在涵道中，构成涵道式双旋翼系统，提供飞行升力和偏航扭矩；碟舱经两个相互垂直的正交关节与双旋翼系统连接，其作用类似摆锤，飞行器的俯仰角滚转角姿态通过关节扭矩进行调节所设计双旋翼碟形飞行器的电气系统为分层递阶结构：组织级以嵌入式工控机为核心，辅以各种人机接口，负责监测获取信息，决策和下达运动控制指令；协调级以DSP为核心，辅以状态感知传感器，主要负责基础的飞行控制；执行级为电机伺服系统，负责控制双旋翼及正交关节的驱动电机以完成指定运动所设计双旋翼碟形飞行器的总体参数包括物理系统参数和气动性能参数，通过对飞行器气动特性的分析，并基于选取的物理系统参数，计算了飞行器的最大负载飞行功率最大爬升速度等飞行性能参数2双旋翼碟形飞行器的建模与动力学分析本文借鉴双旋翼直升机以及涵道风扇飞行器飞行动力学的建模特点，基于直升机桨叶空气动力学原理建立了涵道式双旋翼系统的气动力模型进一步，基于凯恩方程建立了双旋翼碟形飞行器的动力学模型，对飞行器的动力学模型进行了实验验证，实验结果符合物理事实，验证了所建模型的正确性，验证实验也反映了双旋翼碟形飞行器的操稳特性：在零输入时水平姿态具有自稳定性；在零初态时控制响应快速平稳；横向和纵向的动力学特性具有对称性最后对系统的动力学模型进行了分析，建立了偏航通道纵向通道和横向通道子系统模型，并建立了系统的小扰动线性化模型，基于系统的线性化模型，研究了飞行器在定点悬停状态附近的能控能观性和稳定性，能控能观性分析为系统控制器设计提供了依据和指导，稳定性分析结果则验证了飞行器自稳定的特性3双旋翼碟形飞行器的无约束飞行控制本文基于双旋翼碟形飞行器的飞行动力学特点和控制需求设计了飞行器的飞行控制系统，为系统的线性模型非线性模型以及参数摄变的非线性模型分别设计了适用的无约束飞行控制器，完成了姿态控制定点悬停轨迹跟踪以及抗干扰飞行等飞行任务首先，利用双旋翼碟形飞行器的小扰动线性模型设计线性二次型调节器，根据系统模型的耦合特点，为上机身子系统设计了线性二次性最优控制器，实现了对飞行器的姿态控制定点悬停控制和轨迹跟踪控制；其次，设计了双闭环非线性PID控制方法，对横滚角俯仰角和偏航角的控制由内环非线性控制器（Inner NPID）实现，构成系统的内闭环控制，对惯性坐标及速度的控制由外环线性控制器（Outer PID）实现，内环横滚角和俯仰角的期望信号由外环线性控制器（Outer PID）产生，仿真实验检验了双闭环非线性PID控制器的鲁棒性和动态性能，结果表明双闭环非线性PID方法对飞行器非线性模型的控制是可行有效的；最后，针对无人飞行器气动干扰负载变化等因素引起参数变化的问题，为系统的参数摄变非线性模型设计了容错自适应算法，基于李雅普诺夫方法对算法稳定性进行了分析，由于引入的在线估计环节动态补偿了模型参数摄变带来的不利影响，因而保证了参数摄变系统的稳定性和控制精度，仿真实验验证了这一结论4双旋翼碟形飞行器的非线性约束优化控制问题研究针对双旋翼碟形飞行器的非线性约束优化控制问题，根据模型预测控制理论，设计了双旋翼碟形飞行器的非线性模型预测控制器模型预测控制闭环优化的特点保证了控制器具有一定的鲁棒性，稳定性实时性和最优性是双旋翼碟形飞行器模型预测控制器性能改进的主要方向首先，针对模型预测控制核心的有限域优化控制问题（FHOCP）求解问题，提出了一种近似有限域优化控制问题（AFHOCP）来近似代替FHOCP，对预测周期内每一个预测时刻的模型进行递归线性近似化，将复杂的非线性价值函数转化为二次型价值函数，相关理论分析和仿真实验表明，该方法大幅减少优化计算时间，并保证了计算过程的稳定性；其次，在AFHOCP模型预测控制（AFHOCP-MPC）的基础上，针对飞行器纵向通道模型半耦合特点以及模型预测控制预测优化特点，提出了串行预测解耦控制算法，对串行关系的两个子系统分别设计模型预测控制器，利用模型预测控制器的预测信息，建立两个模型预测控制器的串联关系，根据鲁棒模型预测控制理论，分析了串行预测控制器的稳定性，实验结果表明，所设计串行预测解耦控制方法满足了飞行控制实时性和跟踪精度的要求；最后，在串行预测解耦控制方法的基础上，整合李雅普诺夫方法和模型预测控制，设计了滑模模型预测控制算法，基于李雅普诺夫理论分析了算法的稳定性，为了提升算法的实时性，采用分段定值和预先计算控制量策略对算法进行改进，实验结果表明所设计的滑模模型预测控制方法满足了飞行器实时控制的要求，并且在稳定性和优化性能上也获得了预期效果课题获得国家自然科学基金项目(No.61075110)；国家863计划项目(No.2007AA04Z226)；北京市教委重点项目(No.KZ201210005001)；北京市自然科学基金项目(No.4102011)；高等学校博士学科点专项科研基金资助课题(No.20101103110007)的资助取得的科研成果，对于优化碟形飞行器的系统结构，分析碟形飞行器的动力学特性，研究碟形飞行器的飞行控制问题具有积极意义和一定的参考价值课题所设计的样机已获得多项国家专利，在无人机技术和控制科学的研究教学领域，以及军用民用无人机领域有广泛的应用价值更多还原

【Abstract】 Flying saucer is a kind of aircraft using inner rotor system as major power unit. Ithas the ability of VTOL (vertical take-off and landing) and hover, which is similar toa helicopter. Compared with helicopter, flying saucer has special advantages inaerodynamic efficiency and secutity for its built-in rotor system. The research on theflying saucer is still in the development stage, and there are still many problems to besolved about the structure design, aerodynamic optimization, flight control, and so on.The flight performance is unable to meet the needs of practical application, and theconfiguration design, flight control algorithm and other aspects need further researchand development.This dissertation studies and designs a Dual-Rotor Flying Saucer (DRFS), whichhas ducted dual-rotor system and under-mounted pendulum structure. The kinematicsmodel and dynamic model of the aircraft are developed respectively. Based on theanalysis of system characters, the research on the aircraft’s flight control is carried out.The main contributions are as follows:(1) A Maglev Dual-Rotor Flying Saucer SystemThis dissertation illustrates the design of a maglev dual-rotor flying saucer system(DRFS system), whose major structural features includes: the magnetic suspensionmodule is fixed in the end of the rotor, constituting a maglev rotor, and is able toachieve axially positioning the end of the blade; two maglev rotors are fixed up anddown in the duct, which constitute a ducted dual-rotor system, and provode the liftforce and the yawing moment; the cabin is connected with the dual-rotor system bytwo orthogonal joints which mutually vertical to each other, and the moment acting onthe orthogonal joints adjust the attitude of aircraft body. The electronic system of theaircraft is hierarchical architecture: the organization layer has an embeddedIC(Embedded Industrial Computer: EIC), supplemented by a variety ofhuman-machine interface, and it is responsible for monitoring, acquiring information,decision-making and flight control instructions issued; the coordinaton layer has aDSP(Digital Siginal Processor) as the core, supplemented by state sensors, and it ismainly responsible for basic flight control; the execution layer is the motor servosystem, and it is responsible for controlling the motors of the dual-rotor system andthe orthogonal joints. The general parameters of the DRFS include physical systemparameters and aerodynamic parameters. Based on the analysis of DRFS’saerodynamic characters and the choosen physical system parameters, the flyingperformance parameters, such as maximum payload, flying power, maximumclimbing velocity, etc., are calculated.(2) Dynamic Modeling and Analysis of DRFS In this dissertation, the modeling characters of dual-rotor helicopter andducted-fan aircraft are referred, and the aerodynamic model of the ducted dual-rotorsystem is built based on the helicopter blades aerodynamic principles. Furthermore,the dynamic model of DRFS is built based on Kane method, and the dynamic modelis verified by some simulation experiments. The verifying experiments also reveal thehandling and stability characteristics of DRFS: the aircraft has selt-stability with zeroinput; the control response is fast and smooth with zero initial state; the dynamiccharacteristics of longitudinal channel and lateral channel are symmetrical. Finally,the dynamic model of DRFS is analized. The subsystem models of yaw channel,longitudinal channel and lateral channel are built, and the small perturbation linearmodel of DRFS is built, too. Based on the linear model, the controllability,observablity and stability of DRFS in the position-fixed hover status are analized. Theanalysis of controllability and observablity provide foundation and guidance for thedesign of flight controller, and the stability analysis verifies the self-stability of DRFS.(3) Unconstrained Flight Control of DRFSThis dissertation design the flyng control system for DRFS based on the flyingdynamic characters of DRFS and the control requirements. The proper unconstrainedcontrol methods are respectively designed for the linear model, nonlinear model andnonlinear model with parameter disturbance, and accomplish the flight control tasksincluding attitude control, position-fixed hover, trajectory tracking and immunity test.Firstly, the quadratic optimal controller of DRFS is designed based on the smalldisturbance linear model of DRFS, and the linear quadratic regulator (LQR) of aircraftbody is designed according the coupling character of system model. The linearcontroller accomplishes attitude control, position-fixed hover control and trajectorytracking control. Secondly, the dual-loop nonlinear PID control algorithm is designedfor the nonlinear model of DRFS. The attitude control is achieved by inner nonlinearPID controller (Inner NPID), and position and velocity control is achieved by outlinear PID controller (Outer PID). The reference siginals of inner-loop roll and pitchattitude control are produced by Outer PID controller. The simulation verifies therobustness and dynamic performance of the dual-loop nonlinear PID controller, and itshows that the method is feasible and effective for flight control of DRFS. Finally,aiming at solving the parameter’s uncertain change problem caused by aerodynamicdisturbance or payload change, the fault-tolerant adaptive algorithm is designed forthe nonlinear model with parameter’s uncertain change. The stability of the alrorithmis verified based on the analysis of Lyapunov function. Since the on-linear estimationcompensates the bad influence brought by the model parameters’ uncertain change,the stability and control accuracy of the system with parameters’ uncertain change areguaranteed, and this is verified by the simulation results.(4) Research on the Nonlinear Constrained Optimal Control of DRFS This dissertation designs the nonlinear model predictive control (MPC) algorithmfor DRFS based on model predictive control theory. The close-loop optimization ofMPC guarantees the robustness of the algorithm, and the key points of MPC appliedto DRFS are the stability, instantaneity and optimality of the algorithm. Severalalgorithms based on MPC are designed for DRFS. Firstly, considering that thefinite horizon optimal control problem (FHOCP) affects the performance of MPC, anapproximate finite horizon optimal control problem (AFHOCP) is proposed tosubstitute the FHOCP. The method approximately estimates the state variablesequence, and turns the complex nonlinear cost function to a quadratic function. Therelative analysis and experiments show that the method greatly reduces the calculationtime, and keeps the stability of the optimization calculation. Secondly, the serialpredictive decoupling control (SPDC) algorithm is designed according to thehalf-coupling character of DRFS’s nonlinear model, in which MPC controllers arerespectively designed for two sub-systems with serial relation. The serial relation oftwo MPC controllers is built by using the predictive information of the MPCcontrollers. According to the robust MPC theory, the stability of the SPDC algorithmis analized. The simulation result shows that the calculation time is reduced, and theoptimality is improved. Finally, based on the SPDC algorithm, the slide-mode MPC(SMMPC) algorithm is proposed, and its stability is analysized according to theLyapunov stability theory. Piecewise-constant strategy and pre-calculated control areadopted to improve the instantaneity of SMMPC algorithm. The experiments showthat the proposed methods satisfy the requirement of real-time flight control, andachieve expected performance in the stability and optimality.This subject is supported by National Natural Science Foundation of China(No.61075110), China’s863Program (No.2007AA04Z226), Key Project(No.KZ201210005001) of S&T Plan of Beijing Municipal Commission of Education,Beijing Natural Science Foundation (No.4102011), and Specialized Research Fundfor the Doctoral Program of Higher Education (No.20101103110007). The researchresults have significance and reference-value to optimizing the system structure offlying saucer, the analysis of the flying saucer’s dymamic characteristics, and thestudy of flight control problems. Several patents have been granted to the proposedflying saucer, which has application value in the fields of research and education forUAV technology and control science, and military/civilian UAV development.更多还原