Dynamics_of_Flight_Stability_and_Control-MIT课件
Unified Theory for the Dynamics and Control of Maneuvering Flexible Aircraft
Unified Theory for the Dynamics and Control of Maneuvering Flexible Aircraft
Leonard Meirovitch∗ and Ilhan Tuzcu† Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061
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This work represents a new paradigm for the dynamics and control of maneuvering flexible aircraft. Using the system concept, the theory integrates seamlessly all the necessary material from the areas of analytical dynamics, structural dynamics, aerodynamics, and controls. It includes automatically all six rigid-body degrees of freedom and elastic deformations, as well as the gravity, propulsion, aerodynamic, and control forces, in addition to forces of an external nature, such as gusts. The seamless integration is achieved by using the same reference frame and the same variables to describe the aircraft motions and the forces acting on it, including the aerodynamic forces. The formulation is modular in nature, in the the sense that the structural model, the aerodynamic theory, and the controls method can be replaced by any other ones to better suit different types of aircraft, provided certain criteria are satisfied. A perturbation approach permits the separation of the equations of motion into a flight dynamics problem for the maneuvering aircraft rigid-body translations and rotations and an extended perturbation problem for the elastic deformations and perturbations in the rigid-body variables, where the second problem is subject to inputs from the maneuvering aircraft. The formulation is ideally suited for unmanned aerial vehicles (UAVs), and in particular for autonomous UAVs requiring autopilots. A numerical example presents a variety of time simulations of rigid-body perturbations and elastic deformations for two cases, 1) a steady level flight and 2) a level steady turn maneuver. All the time simulations were carried out on a 1-GHz personal computer, which is particularly important for autonomous UAVs, as the required onboard computer is likely to be much closer to a personal computer than to a multiprocessor supercomputer. The unified theory is expected to stimulate new interest in aeronautics research, ultimately providing a useful tool for the analysis and design of flexible aircraft.
第二章 Static Stability and Control
2.2 Introduction
How well an airplane flies and how easily it can be controlled are subjects studied in aircraft stability and control. By stability we mean the tendency of the airplane to return to its equilibrium position after it has been disturbed. An airplane must have sufficient stability that the pilot does not become fatigued by constantly having to control the airplane owing to external disturbances.
Static Stability Stability is a property of an equilibrium state of any dynamic systems. Equilibrium state: the resultant force and the moment about the center of gravity both are equal to zero. Static stability is the initial tendency of the vehicle to return to its equilibrium state after a disturbance while the controls are held fixed.
Through such experiments, it was quickly discovered that for a successful flight, the glider had to be inherently stable. 1893. Zahm concluded that the center of gravity had to be in front of the aerodynamic force and the vehicle would require what he referred to as "longitudinal dihedral" to have a stable equilibrium point. the Wright brothers concluded that powerful controls were essential for the pilot to maintain equilibrium and to prevent accidents.
飞行力学-N飞行动力学习题课一2014
Flight Dynamics3
1.3 说明零升阻力系数CD0、升致阻力系数因子 A 随马赫数 Ma 的变化规律。
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1. CD0随Ma的变化规律：
亚声速：主要是摩阻系数， 随 Ma 变化很小；
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跨声速：波阻出现，零升阻力系数急剧增大；Ma 超声速：激波随 Ma增加而减弱， CD0减小。
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1.5 简要说明涡轮喷气发动机的速度特性、高度 特性和转速特性。
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如何使飞机飞起来英语作文
Airplanes are marvels of engineering that allow us to traverse vast distances in a relatively short amount of time.The concept of making an airplane fly is rooted in a combination of physics,aerodynamics,and engineering principles.Heres an essay on how airplanes achieve flight:The Science of Flight:How Airplanes Take to the SkiesThe ability of an airplane to fly is a testament to human ingenuity and the understanding of natural forces.At the heart of this marvel lies the principle of lift,which is the force that counteracts gravity and allows the aircraft to rise into the air.This essay delves into the intricate processes that enable an airplane to take off,cruise,and land safely.1.The Role of AerodynamicsAerodynamics is the study of how air moves around an object,and in the case of airplanes,it is the science that allows them to fly.The shape and design of an airplanes wings are critical to its ability to generate lift.The wings are typically curved on top and flatter on the bottom,a design known as an airfoil.This shape causes air to move faster over the top of the wing,creating a lower pressure area compared to the higher pressure beneath the wing.This pressure difference results in an upward force,or lift.2.The Importance of ThrustThrust is the force that propels an airplane forward.It is generated by the engines,which can be either turboprops or jet engines.Turboprop engines use a propeller to push air backward,creating a forward thrust.Jet engines operate on the principle of Newtons third law of motion,which states that for every action,there is an equal and opposite reaction. By expelling air at high speed out of the engine,a forward thrust is produced.3.The Balance of Lift and WeightFor an airplane to take off,the lift generated by the wings must be greater than the weight of the aircraft.This is achieved by increasing the angle of attack,which is the angle between the wings chord line and the relative wind.As the airplane accelerates down the runway,the pilot adjusts the control surfaces to increase lift until it overcomes the force of gravity.4.The Control of FlightOnce airborne,an airplane must maintain control throughout its flight.This is managed through the use of control surfaces,which include the ailerons,elevators,and rudder. Ailerons control the roll of the airplane,allowing it to bank left or right.The elevators, located on the horizontal stabilizer,control pitch,enabling the aircraft to climb or descend.The rudder,on the vertical stabilizer,controls yaw,helping the airplane to turn left or right.5.The Role of Air Traffic ControlAir traffic control plays a crucial role in the safe operation of airplanes.Controllers provide pilots with information about weather,air traffic,and other relevant data.They also coordinate the takeoff and landing of aircraft to ensure that they maintain a safe distance from one another.6.The Science of LandingLanding an airplane is a complex process that requires precise control and coordination. As the airplane descends,the pilot reduces the throttle to decrease thrust,and the flaps and slats are extended to increase lift and slow the aircraft down.The pilot must also maintain a stable approach path and touchdown smoothly on the runway.In conclusion,the ability of an airplane to fly is a result of a harmonious blend of science, technology,and human skill.From the moment an airplane leaves the ground to the moment it touches down,a multitude of factors must be considered and controlled to ensure a safe and successful flight.Understanding these principles not only demystifies the art of flying but also highlights the incredible achievements of human innovation and engineering.。
飞行器稳定性与操纵性(英)_西北工业大学中国大学mooc课后章节答案期末考试题库2023年
飞行器稳定性与操纵性(英)_西北工业大学中国大学mooc课后章节答案期末考试题库2023年1.是飞机横向静稳定性的最大来源。
答案:机翼2.短周期自然频率主要取决于以下哪个参数？答案:3.对于无上反的后掠机翼来说，侧滑角会改变哪些参数？答案:弦向速度_局部动压_展向速度4.为降低操纵力，调整片应与操纵面同向偏转。
答案:错误5.右侧扰流板打开时，飞机会向右滚。
答案:正确6.升力系数越高，后掠角对横向静稳定性的贡献越小。
答案:7.同样的飞机，重心适当后移可使飞机的配平性能提高。
答案:8.对于后掠机翼，左侧滑情况下，右侧机翼动压大于左侧机翼动压。
答案:9.侧洗会垂尾前缘处的侧滑角。
Sidewash will the sideslip angle of the verticaltail leading edge.答案:增大increase10.按照本课程的符号定义习惯（国际坐标系），绕x轴向右滚转为，绕z轴向左偏航为。
According to the sign convention in this course (international coordinate system), roll to the right about the x-axis is , and yaw to the left about the z-axis is .答案:正，负positive, negative11.惯性轴系与地轴系之间相差了一个。
The difference between the Inertialsystem and Earth-fixed system is .答案:地球自转earth rotation12.方向舵偏为正，会产生偏航力矩 Rudder deflect to the is positive, and ayawing moment will be generated.答案:左，左left, left13.以下哪些角度是基础体轴系与风轴系间的夹角？Which of the followingangles are the angles between the basic body Axes System and the Wind Axes System?答案:迎角Angle of attack_侧滑角Sideslip angle14.舰载机在起飞离舰瞬间，升力会突然增加。
定常气动力英文
定常气动力英文Constant Aerodynamic ForceConstant aerodynamic force is an important physical concept in aerospace, which is related to the stable flight and performance of a vehicle. Simply put, constant aerodynamic force is the constant force generated by the flow of air over the surface of a vehicle in steady flight. This force plays a vital role in the maneuverability, stability, and overall safety of the aircraft.I. Generation of Constant Aerodynamic ForceWhen a vehicle flies through the air at a certain speed, its surface interacts with air molecules. Due to the special design of the shape of the aircraft, such as the profile shape of the wing, the fuselage of thestreamlined design, etc., the speed of the air flowing through these surfaces will change, which in turn generates pressure differences. These pressure differences are the source of aerodynamic forces, and constant aerodynamic forces are these forces that persist in a steady state of flight.II.Classification of constant aerodynamic forcesConstant aerodynamic forces are mainly categorized into lift and drag. Lift is mainly generated by the wings, enabling the vehicle to overcome gravity and maintain airborne buoyancy and altitude. Drag, on the other hand, is the obstruction force of air in the forward direction of the vehicle, which affects its speed and fuel efficiency. In the design of the vehicle, the balance of lift and drag needs to be considered comprehensively to achieve the best flight performance.III. Influencing factors of constant aerodynamic forceThe main factors affecting constant aerodynamic force include flight speed, air density, shape and size of the vehicle. An increase in flight speed usually leads to an increase in aerodynamic force, but it also increases drag. Changes in air density affect the amount of aerodynamic force, e.g., at high altitudes where the air is thin, the aerodynamic force decreases accordingly. The shape and size of the aircraft is also an important factor in determining the amount ofaerodynamic force, different designs will produce different aerodynamic characteristics.IV. Application of constant aerodynamic forceConstant aerodynamic force has a wide range of applications in the design and operation of aircraft. In aircraft design, engineers accurately calculate and optimize the shape of wings, fuselage and other components to obtain the desired lift and drag characteristics. In flight control systems, constant aerodynamic forces are an important basis for flight stability analysis, and pilots need to adjust their flight attitude and speed according to changes in aerodynamic forces. In addition, in aerospace research, constant aerodynamic force is also one of the important indexes for evaluating the performance of new vehicles.V. Challenges and future development of constant aerodynamic forcesWith the continuous progress of aerospace technology, the research and application of constant aerodynamic forces are facing new challenges and opportunities. On the one hand, with the increase of flight speed and the complexity of flight environment, the calculation and prediction of aerodynamic force become more difficult; on the other hand, the application of new materials, new technologies and new design concepts provides new possibilities for the optimization ofaerodynamic force. In the future, with the development of computational fluid dynamics, artificial intelligence and other technologies, we have reason to believe that the research on constant aerodynamic force will achieve more significant results and contribute more to the development of aerospace industry.In conclusion, the importance of constant aerodynamic force as one of the basic concepts in aerospace is self-evident. Through in-depth understanding and research on the generation, classification, influencing factors and application of constant aerodynamic force, we can better understand and master the flight principle of aircraft and provide more scientific and effective guidance for the design and operation of aircraft.译文：定常气动力在航空航天领域，定常气动力是一个重要的物理概念，它关乎飞行器的稳定飞行和性能表现。
Aerodynamics_of_Flight-1_教材[1]
![Aerodynamics_of_Flight-1_教材[1]](https://img.taocdn.com/s3/m/5732f32f10661ed9ad51f333.png)
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飞行空气动力学 Aerodynamics of Flight 作用在飞机上的力 Forces Acting on the Aircraft
• 推力 Thrust • 阻力 Drag • 重力 Weight • 升力 Lift
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飞行空气动力学 Aerodynamics of Flight
第5页
飞行空气动力学 Aerodynamics of Flight
作用在飞机上的力 Forces Acting on the Aircraft
• 作用于不加速、直线平飞的飞机上的四个力为推力、阻 力、升力和重力。 • The four forces acting on an aircraft in straight-and-level, unaccelerated flight are thrust, drag, lift, and weighmics of Flight
作用在飞机上的力 Forces Acting on the Aircraft
• 升力——抵抗向下的重力，由作用于机翼上的空气的动 力效应产生，作用方向垂直于飞行轨迹，且通过升力中 心。
• Lift - opposes the downward force of weight, is produced by the dynamic effect of the air acting on the airfoil, and acts perpendicular to the flightpath through the center of lift.
作用在飞机上的力 Forces Acting on the Aircraft
• 飞行中的所有飞机都会受到推力、阻力、升力和重力。 理解这些力如何起作用、了解如何使用动力和飞行操纵 来控制它们对飞行很重要。
飞机起飞着陆性能计算模型及其应用分析
飞机起飞着陆性能计算模型及其应用分析飞机的起飞和着陆是飞行过程中最关键的环节之一，其性能计算模型及其应用分析对飞机的飞行安全和效率起着重要作用。
本文将通过对飞机起飞着陆性能计算模型的研究和分析，探讨其在飞机设计和飞行实践中的应用，以及对飞机性能的影响。
一、起飞性能计算模型飞机的起飞性能计算模型主要涉及起飞距离、起飞速度、爬升性能等方面的计算。
起飞性能计算需要考虑飞机的重量、气温、地面条件等多个因素，因此通常采用数值模拟和实测数据相结合的方法进行计算。
起飞性能计算模型的基本原理是根据牵引力和阻力的平衡关系来确定最佳起飞速度和起飞距离。
在起飞性能计算模型中，有必要考虑飞机的动力性能、气动性能和重力因素，以及起飞场地的长度和条件等因素。
还需要考虑飞机在起飞过程中的安全余量和飞行员的操作技能等因素。
这些因素的综合影响使得起飞性能的计算变得相对复杂，通常需要采用计算机模拟的方法来进行分析。
飞机的着陆性能计算模型涉及到着陆距离、着陆速度、下降率等方面的计算。
着陆性能计算模型通常需要考虑飞机的重量、飞行速度、气象条件、着陆场地的长度和条件等因素。
在着陆性能计算中，航空公司和制造商通常会制定一定的标准和规范，以确保飞机着陆时的安全和可靠性。
着陆性能计算模型的基本原理是根据飞机的下降率和阻力的平衡关系来确定最佳着陆速度和着陆距离。
通过综合考虑飞机的构造特点、重心位置、着陆场地条件等因素，可以得出最佳的着陆性能参数。
三、应用分析飞机起飞着陆性能计算模型对飞行员的操作和飞行管理也具有重要的指导作用。
飞行员可以根据起飞和着陆性能计算模型提供的参数和数据，合理地安排起飞和着陆的速度和距离，提高飞行的安全性和效率。
飞机起飞着陆性能计算模型对航空公司的运营管理和飞机维护也有积极影响。
通过合理地识别和评估飞机的起飞着陆性能，航空公司可以优化飞机的飞行计划和安排，减少飞行成本和增加飞行效率。
参数不确定挠性航天器的姿态跟踪控制
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航天器姿态跟踪控制是使航天器的本体坐标系 跟踪惯性空间中的目标坐标系。与刚性航天器的姿 态跟踪控制问题不同…，挠性航天器的姿态控制器 不但要实现姿态跟踪，而且还要对柔性部件进行振 动抑制／控制旧－３１。Ｇｅｎｎａｍ【３叫１基于模态估计器研 究了挠性航天器的姿态跟踪控制问题，他假设描述 在本体系中的相对姿态角速度及其导数满足一定的 约束条件，但该约束条件包含了挠性航天器的状态
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高精度定位系统的摩擦力自适应前馈补偿
电气传动2021年第51卷第4期ELECTRIC DRIVE 2021Vol.51No.4摘要：为了有效抑制机电系统摩擦力等外部扰动对系统动态性能的影响，针对直驱伺服系统中往复定位存在的摩擦力，提出了一种基于自适应前馈控制器的摩擦力补偿策略，此方法能够有效利用参考模型与被控对象的位置跟踪误差等信息，在线实时确定自适应控制率，在保证系统稳定的条件下，能够有效克服系统摩擦力及模型慢时变等引起的系统动态性能异常。
针对直驱伺服系统建立其数学模型，根据数学模型确定自适应补偿环节的数学形式，并利用Lyapunov 函数证明了自适应控制率的稳定性。
最后通过试验表明，在跟踪正弦位置指令时，基于自适应前馈补偿的方法动态跟踪误差的均方根值为4.8μm ，与PID 无摩擦补偿控制方法相比，提高了47.3%，与传统模型参考自适应控制方法相比，提高了17.9%。
综上所述，所提方法可以有效抑制系统摩擦力干扰，提高系统动态跟踪精度。
关键词：自适应；前馈补偿；定位系统；摩擦力中图分类号：TP273+.5文献标识码：ADOI ：10.19457/j.1001-2095.dqcd20741Friction Adaptive Feedforward Compensation for High Precision Positioning SystemYANG Hong ，LI Shengming（College of Electromechanic and Automotive Engineering ，Qingyuan Polytechnic ，Qingyuan 511510，Guangdong ，China ）Abstract:In order to suppress the influence of external disturbances such as friction on the dynamic performance of electromechanical systems ，considering friction force for reciprocating positioning in direct drive servo system ，a friction compensation strategy based on adaptive feedforward controller was proposed.The method can effectively utilize the information of reference model and position tracking error of controlled object and determine the control rate on line.Under the condition of guaranteeing the stability of the system ，it can effectively overcome the abnormal dynamic performance of the system caused by system friction and slow time-varying model.The mathematical model of direct drive servo system and adaptive compensation component were established.Lyapunov function was adopted to guarantee the stability of the adaptive control rate.Finally ，experiments show that the root mean square value of dynamic tracking error based on adaptive feedforward compensation is 4.8μm when tracking sinusoidal position commands ，which is 47.3%higher than that of PID friction-free compensation control method and 17.9%higher than that of traditional model reference adaptive control method.In conclusion ，the proposed method can effectively suppress the friction interference and improve the dynamic tracking accuracy of the system.Key words:adaptive ；feedforward compensation ；positioning system ；friction高精度定位系统的摩擦力自适应前馈补偿杨红，李生明（清远职业技术学院机电与汽车工程学院，广东清远511510）基金项目：广东省高等职业教育教学改革研究与实践项目（GDJG2019380）作者简介：杨红（1969—），女，硕士，副教授，Email ：高精度定位系统广泛应用于航空航天、军工打印机、医疗器械及IC 装备等领域，定位系统的精度和响应速度等指标直接影响军用设备的加工精度及医疗器械的治疗效果等，因此研究有效提高定位系统的精度对国防军工、医疗卫生和生产生活的各领域有着重要意义。
Stability and Turbulence
1 Áwa wa (» ) = 2¼ ©wa wa (-) Ω = Z
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It is often assumed that wa (x) is a sample function from an ergodic random process [Bendat and Piersol, 1966]. An important measure associated with such sample functions is the autocorrelation function, defined as
Hess, R. A. “Stability and Turbulence” The Engineering Handbook. Ed. Richard C. Dorf Boca Raton: CRC Press LLC, 2000
© 1998 by CRC PRESS LLC
173
Stability and Turbulence
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Simplified Descriptions
Concentrating upon turbulence, it is often assumed in aircraft stability and control analyses that the statistical description of the turbulence field (e.g., the RMS velocity at a point) is not a function of time, the origin, or the orientation of the axis system used to describe the field. If, as is typically the case, the aircraft is moving through the field with a velocity that is significantly larger in magnitude than the RMS value of the turbulence velocity at any point along its path, then the
飞行器稳定性与操纵性(英)_西北工业大学中国大学mooc课后章节答案期末考试题库2023年
飞行器稳定性与操纵性(英)_西北工业大学中国大学mooc课后章节答案期末考试题库2023年1.某飞机纵向受扰动后的迎角响应如下图所示，该飞机纵向静，动。
答案:稳定，中立稳定2.A种、B种及C种飞行阶段中，总体来说对飞行品质要求最高的是哪个阶段？答案:A种3.机翼对纵向静稳定性的贡献取决于重心位置，重心前移，飞机纵向静稳定性将。
答案:4.加速飞行时，操纵是符合飞行员操纵习惯的。
答案:推杆5.在平均气动弦上，以下四个点中，位于最前面的是。
答案:松杆中性点6.按照本课程符号定义习惯，飞机感受到来流时侧滑角为正，如果飞机能产生偏航力矩，则飞机航向静稳定。
答案:右侧，右7.是飞机横向静稳定性的最大来源。
答案:8.惯性轴系与地轴系之间相差了一个。
答案:地球自转9.短周期自然频率主要取决于以下哪个参数？答案:10.对于欧拉法坐标变换来说，变换顺序的不同会导致完全不同的坐标，其正确的变换顺序是。
答案:先z轴，再y轴，最后x轴11.初始扰动不为0，操纵输入为0，对应的运动方程解即响应特性被称为，体现的是飞机的。
自由响应，动稳定性12.滚转收敛模态的特征根主要取决于以下哪个参数？答案:13.垂尾对横向静稳定性的贡献是：答案:小迎角时提高稳定性，大迎角时降低稳定性14.当飞机受到右侧滑时，垂尾会产生向的力和向偏航力矩。
答案:左，右15.飞机在做顺时针盘旋时，会由于内外侧机翼速度不等产生偏航力矩。
左16.当特征根是一对实部为负的共轭复根时，可用描述其响应特性。
答案:响应包线的半衰时17.由下图的曲线可以判断该飞机纵向。
答案:时静稳定，静不稳定18.螺旋模态特征根为负时，其飞行品质为。
答案:一级19.飞机的纵向静稳定性与以下哪些参数有关？答案:平尾尾容比重心位置20.战斗机可采用布局来保证大迎角和大M数下的航向静稳定性。
答案:单垂尾+腹鳍双垂尾21.对于常规布局飞机，以下哪些模态是横航向的运动模态？螺旋模态滚转收敛模态22.以下参数中，与荷兰滚模态特性相关的有哪些参数？答案:23.以下哪些操纵面能产生滚转力矩？答案:扰流板方向舵副翼24.以下哪些说法是对的？松杆机动点是单位过载所需杆力为0对应的重心位置握杆机动点是单位过载所需升降舵偏角为0对应的重心位置25.对于无上反的后掠机翼来说，侧滑角会改变哪些参数？答案:弦向速度局部动压展向速度26.对于实部为负的共轭复根，描述其对应模态的特征参数包括。
《飞行力学》8横侧近似开环操纵
2) 双自由度近似
在Mode1和Mode2中两模态的 变化都很小，可近似认为 0 ，并设
侧向气动力 Yp 0,Yr 0,Yv v 0
Dynamics of Flight -----Stability and Control 第十八讲
Nij (s) f (s)
纵向： f (s) (s2 2 phphs ph2 )(s2 2sss s2 )
横侧：
f
(s)
(s
s
)(s
R
)(s2
2 DRDR s
2 DR
)
Dynamics of Flight -----Stability and Control 第十八讲
其中
C u0 Nv , D u0 (Lv N p Lp Nv ) gLv
E g(Nr Lv NvLr )
对算例飞机和状态， 近似解： = -0.00734 =-0.597
S
R
（精确解：1 = -0.0072973 2 =-0.56248）
由此看出，这种近似结果较好，当 与 合成一个振荡模态时（ 12
-2-
类似于纵向模态分析的思路，通过简化分析，来突出各模态的物理性质。
1．Mode 1 螺旋模态
方法：根据特征根进行简化。螺旋模态的特征根比起其它两个模态的
根小得多（二个量级），因此特征方程中关于的高阶项可以忽略， 只取后两项： D E 0
得近似解 E / D 0.00725 （精确解：-0.0072937）
响，故近似方法不可能太简单。
动态定位相关指标
动态定位相关指标
动态定位（Dynamic Positioning，DP）是一种用于控制和稳定船舶或海洋结构物在海上位置的技术。
在动态定位中，一些关键指标用于评估系统的性能和效果。
以下是一些与动态定位相关的常见指标：
定位精度（Positioning Accuracy）：这是衡量动态定位系统性能的主要指标之一。
它表示系统能够将船舶或结构物定位在目标位置附近的精度。
定位精度通常以米（m）或厘米（cm）为单位表示。
响应时间（Response Time）：这是指从接收到指令到系统开始响应所需的时间。
响应时间越短，表示系统对指令的反应越迅速，动态定位的性能越好。
稳定性（Stability）：稳定性是指系统在受到外部干扰（如风、浪、流等）时，能够保持船舶或结构物位置稳定的能力。
稳定性好的系统能够更好地抵抗外部干扰，保持定位精度。
跟踪误差（Tracking Error）：这是指系统实际跟踪路径与目标路径之间的偏差。
跟踪误差越小，表示系统越能够准确地跟踪目标路径，动态定位的性能越好。
燃料效率（Fuel Efficiency）：对于需要长时间运行的动态定位系统，燃料效率是一个重要的指标。
它表示系统消耗燃料的效率，即单位燃料所能提供的定位服务量。
燃料效率高的系统能够降低运行成本，提高经济效益。
这些指标通常用于评估动态定位系统的性能、优化系统配置以及改进系统设计。
在实际应用中，根据不同的需求和场景，可能还需要考虑其他指标，如系统可靠性、维护成本等。
关于飞机起飞滑跑距离的外文文献
飞机起飞滑跑距离是指飞机从起飞开始到完全离地之间所需的距离。
这个距离受到许多因素的影响，包括飞机的重量、气温、气压、风向和速度等。
飞机起飞的滑跑距离对飞行安全至关重要，因此各国的民航管理机构都对飞机起飞滑跑距离做出了严格的规定和标准。
近年来，关于飞机起飞滑跑距离的研究不断深入，国际上有很多学者和研究机构对此进行了系统的研究。
以下是一些详细的外文文献，它们对飞机起飞滑跑距离的影响因素和计算方法进行了详细的分析和总结。
1. Anderson, John D. "Aircraft performance design." New York: McGraw-Hill (1999).本书对飞机性能和设计进行了全面的介绍，其中包括了飞机起飞滑跑距离的计算方法和影响因素。
该书对飞机的气动性能、发动机性能、重量和平衡等方面进行了深入研究，为飞机起飞滑跑距离的计算提供了重要的理论支持。
2. Roskam, Jan. "Airplane Design: Preliminary Calculation of Aerodynamic, Thrust and Power Characteristics." Lawrence, Kansas: Darcorporation (1990).该书主要介绍了飞机的气动特性、推力和动力特性的初步计算方法。
在此基础上，对飞机起飞滑跑距离的计算进行了详细的讨论，包括了在不同气候条件下的影响因素和修正方法。
3. Clancy, L. J. "Aerodynamics." John Wiley Sons (2005).本书是一本飞机空气动力学的经典教材，对飞机的气动性能进行了系统的介绍。
其中包括了飞机在不同条件下的起飞性能和滑跑距离的计算方法，为飞机设计和运行提供了重要的参考。
4. Torenbeek, Egbert. "Advanced 本人rcraft design: conceptual design, technology and optimization of subsonic civil 本人rplanes." John Wiley Sons (2013).该书介绍了现代飞机的概念设计、技术和优化方法。
737空速表的参考文献
标题：737空速表的参考文献
正文：
关于737空速表的参考文献，可以参考以下资料：
1.《波音737飞机飞行指南》-波音公司官方出版物，详细介绍了737飞机的各种系统，包括空速表系统。
2.《飞机仪表与控制系统》-航空类教材，详细介绍了各种飞机仪表和控制系统的工作原理，其中也包括空速表的原理和结构。
3.《航空仪表与传感器》-航空类教材，其中涉及空速表的工作原理和结构，以及其在飞行中的重要性和作用。
4.《航空电子与通信系统》-航空类教材，其中涉及空速表与飞行控制系统、导航系统等的接口和交互，以及其在飞行中的实际应用。
5.《航空器适航与安全》-航空类教材，其中涉及空速表等飞行仪表的适航要求和校准要求。
6.《民航飞机维护与排故技术》-民航类教材，其中涉及737飞机的各种系统和部件的维护和排故技术，包括空速表的维护和排故技术。
7.《空速表误差分析及其修正》-专业论文，深入探讨了空速表的误差来源、误差特性以及误差修正的方法和措施。
动态精度 英语
动态精度英语
动态精度英语：dynamic accuracy。
例句：
1、最后，设计了动态精度检测系统，并测量了其动态精度。
At the end, the dynamic precision detects system were designed and the dynamic precision was also measured.
2、火控系统精度试验包括检验火控系统的静态精度和动态精度。
The accuracy test of the fire control system consists of static accuracy test experiment and dynamic accuracy test.
3、动态精度已引起人们的高度重视，成为精度理论研究中迫切需要解决的课题。
Great attention has been aroused in dynamic accuracy, which becomes an urgent need to address issues in theoretical research on accuracy.
4、现代机电系统对各种极限工况条件下的动态精度和稳定性提出了越来越高的要求。
Nowadays, the Mechatronical Systems need stricter requirement of dynamic precision and stability in the utmost condition.。
无人机动力学特征和运动学特征
无人机动力学特征和运动学特征英文回答：Dynamics and kinematics are two important aspects of unmanned aerial vehicles (UAVs) that determine their behavior and capabilities.Dynamics refers to the study of forces and torques that affect the motion of UAVs. It involves understanding how the UAV responds to external forces and how it generatesits own forces for propulsion and control. The dynamics of a UAV can be described by its equations of motion, which take into account factors such as mass, inertia, aerodynamic forces, and control inputs. By analyzing the dynamics, we can predict the UAV's stability, maneuverability, and response to different flight conditions.For example, when a UAV is subjected to a gust of wind, its dynamics determine how it reacts to the sudden changein airflow. If the UAV has a stable and well-designed control system, it will be able to quickly adjust its control surfaces and maintain its intended flight path. On the other hand, if the dynamics are not properly understood or the control system is not robust, the UAV may experience instability or even lose control.Kinematics, on the other hand, deals with the motion of UAVs without considering the forces that cause the motion. It focuses on describing the position, velocity, and acceleration of the UAV without considering the underlying forces and torques. Kinematics is useful for understanding the motion of UAVs in a mathematical and geometric sense, without the need to consider the complex dynamics involved.For example, if we want to plan a trajectory for a UAV to fly from one point to another, we can use kinematics to determine the desired position, velocity, and acceleration at each point along the path. By considering the kinematic constraints of the UAV, such as its maximum speed and turning radius, we can design a trajectory that is feasible and optimal for the given mission.In conclusion, dynamics and kinematics are two fundamental aspects of UAVs that play a crucial role in their behavior and capabilities. Understanding the dynamics helps us predict and control the UAV's response to external forces, while kinematics allows us to describe and plan its motion without considering the underlying forces. By studying both aspects, we can design and operate UAVs that are safe, efficient, and capable of performing complex tasks.中文回答：动力学和运动学是无人机（UAV）的两个重要方面，它们决定了无人机的行为和能力。
典型飞行控制系统
典型飞行控制系统
Chen Yongliang
Nanjing University of Aeronautics and Astronautics Department of Aerodynamics
1
典型飞行控制系统的构成 典型的飞行控制系统一般由三个反馈回路构成，即舵回路、 稳定回路和控制（制导）回路. 舵回路:为了改善舵机的性能以满足飞行控制系统的要求，通 常将舵机的输出信号反馈到输入端形成负反馈回路（或称为 伺服回路）的随动系统（或称为伺服系统）.
控制增稳系统
11
俯仰控制增稳系统的方框图 当无操纵信号时，此控制增稳系统只起增稳的作用.
12
5
阻尼器与增稳系统
现代高性能飞机的典型飞行包线 为改善飞机的角运动性能，引入阻尼器和增稳系统.
6
阻尼器和增稳系统在飞机起飞时就已经接入，不像自动驾驶仪 那样，需要首先建立基准工作状态。这种增稳系统与驾驶员共 同操纵飞机的方式，是有人驾驶情况下的自动控制问题.
飞机纵向运动方程Leabharlann oror7
阻尼器
由自动控制理论可知，为了改善飞机角运动的阻尼特性，直 接引入姿态角的变化率，形成反馈回路就可以调节飞机角运 动的阻尼比，从而改善飞机的运动品质.有俯仰阻尼器、滚转 阻尼器和偏航阻尼器。
舵回路方框图
2
如果测量部件测量的是飞机的飞行姿态信息，则姿态测量部件 和舵回路就构成了自动驾驶仪；自动驾驶仪和被控对象（飞机） 又构成了稳定回路，主要起稳定和控制飞机姿态的作用。
3
由稳定回路和飞机重心位置测量部件以及描述飞机空间位置几 何关系的运动学环节构成了控制（制导）回路，主要起稳定和 控制飞机的运动轨迹的作用.
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Prof. Newman, 2004 Page 8
Design Elements
• Aspect Ratio (b2/S)
Prof. Newman, 2004 Page 2
Performance
• Note: Book errata pdf file • Speed: minimum and maximum? • Range: How far? • Endurance: How long? – Flight dynamics
Prof. Newman, 2004 Page 5
Aircraft Performance/Design Elements
• Second example: “Omega” high performance motor-glider
• ~ 1.8 m span, 300 grams weight
Prof. Newman, 2004 Page 6
Prof. Newman, 2004 Page 15
Examples
• Example 4.6, pg. 90, V-n Simulation • Problem 4.6 Calculate the thrust required for an aircraft, modeled after a Canadair Challenger Business Jet, to maintain steady level flight of 350 knots at an altitude of 6500 meters. Assume the following characteristics for the aircraft: Weight = 16,350 kg, Wing area = 48.31, Wing span = 19.61 m, Parasite drag = CDo = 0.02, Oswald efficiency factor = e = 0.8
Discussion Topic
• What are the differing aerodynamic design features providing the desired performance for each aircraft? • Common features: – Aero controls: elevator, ailerons, rudder – Electric motor: identical – Radio receiver and servo motors: identical
• Performance Parameters
– Aircraft components and examples
• Equations of Motion • Thrust-Velocity Curves
– Stall – Lift-to-Drag Ratio
• Endurance & Range • V-n Diagrams
Prof. Newman, 2004 Page 9
Equations of Motion
• 2-D model of aircraft • Lift, Drag, Weight and Thrust • Velocity, v • Flight path, q or g – Velocity & horizontal • Pitch angle – Nose & horizontal
Thrust-Velocity Simulation
• Simulations • Foil Sim
https:///16.00/www/3/03/index.html /WWW/K-12/airplane/foil2.html /simulators/atmospheric.htm
Aircraft Performance
Prof. Dava Newman Sr. Lecturer Pete Young 16.00: Introduction to Aerospace & Design 12 February 2004
Prof. Newman, 2004 Page 1
Lecture Outline
Prof. Newman, 2004 Page 13
• Endurance: total time a/c can stay aloft on a tank of fuel
Range & Endurance
Prof. Newman, 2004 Page 14
V-n Diagrams (Flight Envelope)
Prof. Newman, 2004 Page 16
Questions?
• Mud Cards
Prof. Newman, 2004 Page 17
• Operational Velocity-Load (in g’s, denoted by ‘n’) envelope • Aerodynamic • Structural • Simulator – Stall limit: aerodynamic – Corner Velocity or Maneuver point – Structural limit
Prof. Newman, 2004 Page 10
Thrust-Velocity Curves
• The relationship between the required thrust and the velocity can be calculated for any aircraft.
Prof. Newman, 2004 Page 11
• Air Density Simulator
• Stall • Maximum Lift/Drag
Prof. Newman, 2004 Page 12
Range & Endurance (Breguet)
• Aerodynamics & Engines (propeller, jets) – mo = a/c, kg – mf = mass of fuel, kg m= mo +mf – ˙mf = fuel mass flow rate, kg/s • Range: total distance on a tank of fuel – (L/D)max – (CL3/2/ CD)max (CL1/2/ CD)max or v(L/D) (L/D)max
Prof. Newman, 2004 Page 3
Aircraft Components
Prof. Newman, 2004 Page 4
Aircraft Performance/Design Elements
• First example: – Semi-scale Mustang “Reno Racer” – ~ 750 cm span, 450 grams weight
Prof. Newman, 2004 Page 7
Desired performance
• Reno Racer: high speed aerobatics and racing – 20-25 m/s velocityns and rolls
– Low or high? Why?
• Drag reduction: how attained? • Airfoils: low or high camber? Why? • Tail moment arm (horizontal stab area x tail length): high or low? Why? • Wing loading (wing area/weight) high or low? What effect on flight? • Any other differing design features?