无人机动态空中对准算法及性能仿真研究

关于无人机导航精度优化问题,高空长航无人机航行时间长,而惯导误差随时间积累,所以长航时无人机在进入目标区域进行SAR(合成孔径雷达)侦察时产生导航误差,不能满足匹配要求,所以必须进行空中对准,以提高导航系统精度。为了有效提高对准的精度,明确载体机动对对准效果的影响,设计了高空长航无人机机动对准方案,在建立SINS/GPS速度和位置组合模式的卡尔曼滤波器模型的基础上,综合分析比较了不同机动方式对对准效果的影响。仿真结果证明,在速度位置组合模式下,"S"机动方式对空中对准的效果改善最大,且机动强度对对准效果也有影响;仿真结论为后续研究无人机长航时保持惯导精度提供重要参考依据,对提高组合导航性能具有重大意义。     

基于知识库的无人机作战自主决策方法的研究

提高无人机的自主决策能力是提升无人机在现代战争中作战能力的重要手段。通过对无人机对地作战过程的研究,分析归纳影响无人机自主决策的相关因素,并将无法用数学模型描述的军事规则使用产生式规则来表达,建立作战规则库。然后提出一种基于知识库的自主决策方法,该方法通过动态贝叶斯网络模拟人对态势的认知,通过产生式规则进行决策,其中加入实体的状态描述来控制决策流程,以此来完成无人机的自主决策。仿真结果表明,该方法科学有效,可使无人机自主做出合理决策。     

Robust dynamic surface trajectory tracking control for a quadrotor UAV via extended state observer

In this paper, we present an extended state observer–based robust dynamic surface trajectory tracking controller for a quadrotor unmanned aerial vehicle subject to parametric uncertainties and external disturbances. First, the original cascaded dynamics of a quadrotor unmanned aerial vehicle is formulated in a strict form with lumped disturbances to facilitate the backstepping design. Second, based on the separate outer‐ and inner‐loop control methodologies, the extended state observers are constructed to online estimate the unmeasurable velocity states and lumped disturbances existed in translational and rotational dynamics, respectively. Third, to overcome the problem of “explosion of complexity” inherent in backstepping control, the technique of dynamic surface control is utilized for trajectory tracking and attitude stabilization, and with the velocity and disturbance estimates incorporated into the dynamic surface control, a robust dynamic surface flight controller that guarantees asymptotic tracking in the presence of lumped disturbances is synthesized. In addition, the stability analysis is given, showing that the present robust controller can ensure the ultimate boundedness of all signals in the closed‐loop system and make the tracking errors arbitrarily small. Finally, comparisons and extensive simulations under different flight scenarios are performed to validate the effectiveness and superiority of the proposed scheme in accurate tracking performance and enhanced antidisturbance capability.     

基于PID和LQR的四旋翼无人机控制系统研究

为提高四旋翼无人机的飞行稳定性、无人飞行器控制系统的鲁棒性和控制精度,以建立的四旋翼无人机飞行控制系统模型为基础,采用现代控制理论与传统控制论相结合的方法,针对姿态角速率、姿态角分别设计内环LQR(线性二次型调节器)控制器,及外环PID控制的双回路闲环控制器.充分利用PID控制器易于掌握且对模型要求精度低、LQR控制器能改善内回路的动态特性和稳态性能的特点,完成四旋翼无人机的飞行控制.通过实验遴选该双闭环控制器相关参数并进行优化,实验结果表明所设计的双回路控制器控制性能指标良好.     

基于神经网络的无人机滑模飞行控制设计

针对无人机受扰运动,基于Backstepping方法和非线性滑模控制提出了一种鲁棒神经网络飞行控制方案。对无人机姿态角速度层的系统不确定性项,采用径向基函数神经网络并对其权值进行在线调整,从而实现对其进行逼近。将回馈递推设计方法与滑模控制方法结合起来,基于神经网络的输出为无人机设计了一种回馈递推滑模飞行控制器。所设计的飞行控制器用于无人机的姿态控制,仿真结果表明所研究的无人机鲁棒神经网络飞行控制方案是有效的。     

基于无人机航拍的油气管道监管系统设计与实现

油气管线布设范围广、跨度大,对于安全性要求极高,日常检修工作繁重。为了提高检修效 率,该文提出并开发了一套基于无人机航拍的油气管道监管系统。系统采用浏览器/服务器架构,结合网络地理信息系统(WebGIS)和云平台技术,实现了轨迹规划、飞行任务管理、无人机飞行数据、飞行轨迹、航拍视频实时显示、检测识别预警、历史回放等功能。实验结果表明,该系统可靠实用,可使石化工作人员及时有效地了解管道情况,对管道损坏或灾情异常做出及时应对,达到了油气管道全面有效的远程监测和管理。     

基于网络的飞行传感器仿真系统研究

提出了一种基于TCP／IP协议的传感器仿真系统,模拟无人机实际飞行中各类传感器的信导和电气特性,解决了全数字无人机飞行仿真系统中对飞机传感器进行实时仿真的问题。     

低空无人机航空摄影高度自动测量方法研究

为控制低空无人机摄影高度,获得更加清晰的地理信息图像,需要对低空无人机摄影高度自动测量方法进行优化研究;当前方法主要利用射影几何知识的自动化标定方法实现低空无人机航空摄影高度的自动测量;该方法存在噪声影响严重,且测量误差较大的问题;为此,提出一种基于多传感器与卡尔曼滤波相结合的低空无人机航空摄影高度自动测量方法;该方法首先通过分析气压测量法计算各种气压因素对低空无人机航空摄影高度的影响,然后推导出大气对流层内气压随低空无人机航空摄影高度的变化;然后采用双GPS系统同时工作,对GPS、气压高度计和IMU测量获得的低空无人机航空摄影高度信号进行冗余备份;采用基于二阶多项式的修正方法对低空无人机航空摄影传感器输出值进行补偿和修正;根据动力学方程建立低空无人机航空摄影的动力学方程获得高度测量状态方程;最后采用卡尔曼滤波的线性最小方差估计准则对低空无人机航空摄影高度进行均方差估计计算,实现低空高度自动测量与校正。实验结果表明,所提方法具有精度高、收敛性好且滤波效果理想的优势。     

无人机飞控/导航系统便携式测试仪设计

针对当前某型无人机飞控/导航系统现场联调发生故障时无法快速定位故障点而造成调试周期过长的问题,根据有固定航姿参数输入的飞控/导航系统会产生固定输出的原理,提出并实现了一种基于现场测试仪的快速诊断方法;基于DSP和CPLD的便携式飞控/导航系统测试仪通过实验电缆把测试仪与被测设备相连,可以方便、直观、快捷、可靠地确定出被测设备是否存在故障。     

Transformable multirotor with two-dimensional multilinks: modeling,control, and motion planning for aerial transformation

In this study, we investigated a novel type of the multirotor aerial vehicle with two-dimensional multilinks to demonstrate stable aerial transformation for high mobility in three-dimensional environments. Our goal was to tackle the challenge of traversing narrow spaces or gaps, which is one of the difficulties for existing structure of multirotors, especially in the cluttered indoor environment of disaster sites. The research involved three steps. First, we developed the modeling of the link modules that compose a multirotor with two-dimensional multilinks and conducted a quadrotor prototype. Second, we derived a stable flight control method for aerial transformation on the basis of linear-quadratic-integral optimal control. Third, we investigated the motion planning for the aerial transformation using a state validation method and path optimization in the joint space to maintain the stability during transformation. Successful aerial transformation and the ability of the prototype to negotiate narrow gaps were demonstrated, confirming the feasibility and utility of our proposed transformable multirotor for aerial maneuvering in complex three-dimensional environments.     

油气田环境巡视小型无人飞行器航姿控制系统

针对小型无人飞行器在油气田现场采集信息时的高精度控制问题,提出一个自适应卡尔曼滤波算法来获得高精度姿态信息,并采用优化模糊控制方法构建航向控制算法．基于航向误差在线调整飞控参数,为远程控制中心提供精确的油气田现场信息来提高决策效率．最后,通过一系列的仿真和实际飞行试验验证了该方法的有效性．     

无人机感知-规避系统安全区域动态决策方法

为了解决无人机在空域交通中的感知-规避安全性需求问题,根据无人机的感知能力定义空域交通的安全边界,采用微分对策和生存能力理论对感知-规避问题进行描述和分析,提出一个理论框架和解决方案,给出了安全区域对无人机飞行策略和制导律的影响。只要无人机与冲突航线内的其他飞行器保持必要的间隔,所提出的方法就可采取有效的策略减小冲突航线上的不确定边界,并选择相应的规避决策调整航线,避免飞行冲突。     

Altitude control for flexible wing unmanned aerial vehicle based on active disturbance rejection control and feedforward compensation

For achieving the accurate trajectory tracking of the flexible wing unmanned aerial vehicle in the complicated missions, especially the vertical component, a feedforward compensation unit–based active disturbance rejection control (ADRC) is proposed. In ADRC, the internal dynamics and complicated influence of the total disturbance will be estimated and dynamically compensated by extended state observer (ESO). It puts a very high request on the observation ability of ESO with the unpredictable external disturbance, complex internal coupling influence, and the strong nonlinear characteristic of the proposed system. For this reason, by deeply analyzing the model of this system, the varying attitude influence on the altitude control will be deduced. Then, this influence will be compensated previously by a feedforward compensation unit. Through the previous compensation of the calculable part of the internal dynamics and total disturbance, the burden of ESO can be reduced largely. In this way, it improves the control effect of the ADRC with better observation precision of ESO. After that, based on the hardware‐in‐the‐loop simulation, the effectiveness of the proposed method is verified completely with the complicated flight missions. The robustness of the control effect and observation ability of ESO are also verified by the Monte Carlo simulation. At last, the results of actual flight experiment prove the advancement and practicability of the proposed ADRC method.     

Design and implementation of an autonomous flight control law for a UAV helicopter

In this paper, we present the design and implementation of an autonomous flight control law for a small-scale unmanned aerial vehicle (UAV) helicopter. The approach is decentralized in nature by incorporating a newly developed nonlinear control technique, namely the composite nonlinear feedback control, together with dynamic inversion. The overall control law consists of three hierarchical layers, namely, the kernel control, command generator and flight scheduling, and is implemented and verified in flight tests on the actual UAV helicopter. The flight test results demonstrate that the UAV helicopter is capable of carrying out complicated flight missions autonomously.     

小型无人机飞行控制器的硬件设计

以80C196KC单片机和可编程微控制器外围器件PSD813F1为核心设计了小型民用无人机飞行控制器的硬件，对设计中的关键技术进行了研究，系统具有设计精炼，可靠性高，开发性等特点。     

UUV侦察水雷作业模式效率评估仿真研究

侦察水雷是水雷战的一项重要内容,也是水下无人作战平台(UUV)的一项重要作业任务.经研究,提出了水下无人作战平台执行侦察水雷任务的二种作业模式,为对二种作业模式的效率进行评估,给出了作业区的水雷分布模型,在分析二种作业模式侦察水雷作业过程的基础上,利用贝叶斯定理和统计学方法,建立了水下无人作战平台使用二种作业模式侦察水雷作业效率的评估仿真模型,并结合简单想定进行了计算机仿真,得出了评估仿真结果.为水下无人作战平台选择作业模式提供了理论依据.     

基于ARM的某型无人机飞控计算机设计

作为无人机飞控系统的核心,飞控计算机通常采用基于嵌入式系统的实现方案;ARM嵌入式处理器及Linux嵌入式操作系统以其一系列优点在飞控计算机中具有广泛的应用前景;研究了基于ARM-Linux的某型无人机飞控计算机的实现方法,给出了系统总体设计方案,着重介绍了硬件电路的设计过程,列出了软件调试流程图,分析了调试结果;实践证明,该实现方法结构简单,功能强大,能够满足系统控制的要求,具有较好的实用性。     

基于拓扑优化的四旋翼无人机结构设计

为实现某四旋翼无人机的轻量化结构设计,采用Inspire进行拓扑优化设计,并对获得的拓扑优化结构进行静力分析和动力学分析。分析结果表明,通过拓扑优化方法获得的无人机结构应力分布合理,结构位移小且频率较高,满足静态和动态结构设计要求。研究结果可为实现低成本、轻量化的四旋翼无人机结构设计提供一条新的途径。     

Formation control of unmanned aerial vehicle swarms: A comprehensive review

The unmanned aerial vehicle formation plays a crucial role in numerous applications, such as reconnaissance, agricultural plant protection, and electric power inspection. This paper provides a comprehensive review and analysis of the unmanned aerial vehicle swarm communication networks and formation control strategies. First, the most commonly used unmanned aerial vehicles are introduced and compared. Next, the entire process of the formation task, from the formation assignment to the formation transformation, is detailed described. At last, the widely adopted communication networks are analyzed, and the existing formation control strategies of the UAV swarm are compared, which shows that the distributed formation control is superior to the centralized method and is the future development trend.     

无人机模糊飞行控制器设计

近年来,无人机凭借其各种优势,受到了各国越来越多的关注;飞行控制系统是现代无人机的核心,其控制律设计结果对无人机飞行特性的影响至关重要,决定无人机是否能够满足自主飞行要求;为了获得更好的控制效果,保证无人机能更好地适应复杂环境和任务,在常规模糊控制方法的基础上引入修正因子和积分抑制策略,设计出了一种模糊飞行控制器;仿真结果表明,该控制器具有较好的控制效果和较强的鲁棒性,较一般的模糊控制系统具有控制速度快、精度高、鲁棒性强等特点,更能适应无人机的特殊要求.