某型舰载直升机飞行模拟器飞行仿真系统设计

对某型舰载直升机飞行模拟器飞行仿真系统进行了设计研究.给出了某型舰载直升机飞行模拟器飞行仿真系统的模型框架.定义了建模过程中所涉及的主要坐标系,研究与分析了与主旋翼相关的诱导速度、挥舞角、拉力、扭矩的计算方法,给出了舰载直升机部件气动建模思路.最后,结合舰载直升机数据,对直升机飞行模拟器飞行仿真系统对舰载机飞行员的操纵响应进行了仿真分析.设计的舰载直升机飞行模拟器飞行仿真系统已经成功应用到了某型舰载直升机飞行模拟器上,具有仿真度高、实时性好等特点,起到了良好的训练效果,得到了舰载直升机飞行教员和学员的认可.     

近场记录光盘头盘间距控制的仿真研究

本文对波导锥尖近场记录方案中写入能量与头盘间距进行了建模与分析 ,通过仿真计算得出了它们之间的影响曲线 ,进而确定了飞行光学头飞行高度波动的允许范围 .     

飞行模拟器的结构设计与仿真研究

飞行模拟器具有真实飞行训练无法比拟的优势,其结构设计是优化飞机设计,改善飞行性能的关键问题,故飞行模拟器的建模与仿真研究工作是飞行器设计的难点。通过与液压缸驱动的六自由度飞行模拟器对比分析,以3-RPS机构为基础,以在UG环境下建立的电动缸驱动的三自由度飞行模拟器运动平台模型为研究对象,在ADAMS/View模块下,对其添加约束和驱动后,进行了运动学特性仿真。对于给定的运动学特性曲线,运用ADAMS/Post Processor模块,对测量结果进行后处理,得到各种飞行姿态下的运动学曲线。仿真实验结果验证了该设计可实现升降、横滚、俯仰三种姿态的运动,且符合民航飞行模拟器的技术指标要求。上述分析过程为飞行模拟器的设计提供了一套有效的研究方法。     

基于面向对象技术的飞行仿真研究

针对当前在飞行仿真建模领域遇到的模型重用性差,设计模式不统一,不能适应冠代军用飞行仿真需求的问题,尝试在工程实践中引入面向对象的设计方法,实现规范仿真建模过程的目的.通过研究面向对象技术在飞行仿真系统研制中的应用范围与应用方法,结合实际项目中飞机导航系统的仿真过程,使用面向对象技术对其进行分析与设计,并据此建立了仿真模型.利用这种方法建立的仿真模型清晰明了,易于理解,有效地增强了系统的可重用性和继承性,收到了良好的应用效果,证明了将面向对象技术应用于飞行仿真领域是可行的.     

高超声速飞行器飞行轨迹的模糊控制设计

针对高超声速飞行器飞行过程中因干扰造成的飞行轨迹散布问题,提出了采用飞行器飞行轨迹的模糊控制设计方法。方法以高超声速飞行器飞行轨迹线偏差和线偏差变化率作为模糊控制器输入,采用模糊推理设计飞行控制系统。在完成高超声速飞行轨迹控制系统数学建模的基础上,结合自动驾驶仪特点对飞行轨迹模糊控制系统进行了设计。结论通过仿真表明所设计的飞行控制系统满足飞行轨迹及攻角性能要求,验证了方法的正确性。     

飞行仿真中的TCAS建模方法

介绍了飞行仿真系统中空中交通警戒与防撞系统(TCAS)的一种仿真实现方法.对闯入飞机进行了运动方程建模,介绍了TCAS基本参数计算方法,分析了TCAS系统逻辑,利用全局处理模式设计了实时仿真中的完备的逻辑处理流程,完成了实时仿真系统中的TCAS仿真,该建模方法已在某项目中成功投入使用.     

基于模型驱动构件库的飞行控制软件工厂研究

针对飞行控制软件日趋紧张的型号进度和快速增长的代码规模,首先,提出了基于模型驱动构件库开发飞行控制软件的基本概念,并与传统软件开发方法进行了对比分析;然后,针对飞行控制软件快速开发的需求,根据构件的设计准则,对飞行控制软件功能、性能、软件和硬件组成、接口关系进行领域工程建模;对飞行控制软件的共性通用部分和型号定制部分解耦后进行分层和领域构件化分析,建立了软件工厂模式的开发平台框架;最后,详细讨论了基于模型驱动构件库的软件工厂实现和维护的关键技术。     

直升机贴地飞行模型跟踪控制器设计研究

为了设计直升机实施贴地飞行时的飞行控制系统,研究了基于内/外回路控制结构的直升机模型跟踪飞行控制器,引入了模型跟踪性能判据,分析了显模型的动态特性以及增益矩阵等参数的优化设计对控制系统模型跟踪性能的影响;对于贴地飞行中实施的鱼跃障碍机动飞行,设计了模型跟踪控制器,对于直升机对正弦形式垂向速率指令和俯仰指令的跟踪进行了仿真;通过对仿真结果的分析说明了模型跟踪控制技术在直升机贴地飞行控制中性能良好,有很好的应用前景.     

四旋翼无人机的室内自主飞行控制

为了解决四旋翼无人机在室内等无GPS信号的复杂环境中实现自主飞行的问题,在对四旋翼无人机进行非线性建模的基础上,分别设计了基于反步法结合滑模理论的姿态控制器和基于PID的位置控制器.考虑到激光测距仪高昂的价格,提出一种基于红外传感器和扩展卡尔曼算法(EKF)实现无人机室内自主飞行定位的方法,通过无人机的旋转运动弥补红外传感器每次只能测量单一点距的缺陷.最后,通过仿真验证所设计的控制器和定位算法的性能.Wyfh2结果证明了所设计的四旋翼无人机室内自主飞行方法的有效性和可靠性.     

基于DirectX的无人机三维虚拟飞行仿真系统开发

建立无人机三维虚拟飞行仿真系统对于无人机的设计、研制与操纵培训具有重要的意义.介绍了一种低成本的基于PC机的无尾式无人机实时三维虚拟飞行仿真系统,对建模与仿真、DirectX、数据库、面向对象编程等技术在可视化系统仿真领域的应用作出了积极的探索与尝试.介绍内容主要为三维仿真建模接口技术比较与采用、无人机飞行仿真系统模型组成与仿真算法采用以及如何运用软件工程概念开发无人机实时飞行仿真软件系统.     

采用数据驱动实现飞行仿真的一种实际方法

飞行数据记录器记录了大量的飞机飞行性能、飞行状态数据。从飞行数据中生成反映飞行过程的三维动画是飞行数据处理的一项重要任务。该文应用面向对象技术 ,给出了关系数据库驱动的飞行仿真动画系统的设计思想和实现方法 ,并把它用在了西南航空重庆公司飞行品质监控的实际工作中 ,取得了良好效果。     

Readout signal evaluation of optical flying head slider with visible light-wave guide flexure

 The need for both higher recording density and faster transfer rates continues to propel the research and development of high-performance storage equipment. The optical first-surface recording method promises to overcome tough optical diffraction limits and/or wavelength-shortening limits. We have already proposed a novel compact optical head suspension assembly combining a flying optical slider with a resin-based flexible light-wave guide flexure, and we have confirmed this assembly's stable flying performance during head-arm out-of-plane disturbances. Following this technical progress, we here describe the successful detection of optical signals of sub-micron-size bits by flying this slider above a metal patterned medium through spacing of several tens of nanometers. Signal amplitude dependencies upon both bit pattern lengths and spacings are evaluated in detail, and it is predicted that sub-micron-long and -wide bit will be able to detect increasing the incident laser power up to its maximum value of several mW in our system. Received: 22 June 2001/Accepted: 1 November 2001     

飞翼布局无人作战飞机自动着陆控制系统设计

飞翼飞机是一种先进的飞行结构.但由于气动外形的特殊,无垂直尾翼的飞翼飞机在着陆阶段,极易受到侧风的干扰,而使其偏离航线;根据飞翼飞机的气动参数,建立了飞翼飞机的非线性数学模型,设计了飞翼无人机的着陆轨迹和控制方案;针对飞翼飞机的特性,采用不同于常规飞机的控制律,设计了抗侧风自动着陆控制系统;设计的控制系统经过非线性仿真试验,结果显示,飞机抗侧风着陆性能达到了设计要求,从而验证了设计方案的可行性.     

Application of megasonic cleaner to sub-micron particles of SIL optical flying head

 As the demand for large capacity storage drives has increased, the flying height of near-field recording (NFR) sliders becomes as small as 100 nm for super high storage density. Accordingly contamination problems have been a concern of information storage industry because it may cause a serious damage to solid immersion lens (SIL) of optical flying head. Sub-micro contaminants in air bearing of the NFR slider may affect the flyability and stability of the optical slider. In addition, the cleaning of small particles becomes more difficult as the contaminant particle size decreases because the adhesion force increases very much as the particle size decreases. Recently developed high-frequency ultrasonic (megasonic) cleaning technique have made it possible to remove sub-micron particles less than 100 nm without surface erosion and many remarkable results have been reported. In this paper, the megasonic technique is applied and tested for the cleaning of the flying head of NFR drive. 1 MHz ultrasound with maximum 100 W was used to remove polystyrene latex (PSL) particles and alumina particles deposited on the surface of the slider. Effective cleaning performance was observed without any damages on the slider surface using optical microscope and AFM at different ultrasonic energy levels and cleaning times. Received: 20 June 2002 / Accepted: 9 September 2002     

基于视觉反馈的近场微型飞行头定位系统

近场光存储方案中,头盘间距动态测控技术是将近场光存储理论和技术实用化的一项关键技术。基于强度干涉原理的飞高检测方案中,微型飞行头位姿控制是影响测量误差的一项关键因素。提出一种基于视觉反馈的定位控制系统,重点介绍其系统结构,分析机械控制元件和图像处理算法精度。试验表明,微型飞行头定位系统精度优于11μm,引起飞高检测误差在1nm范围内,满足高精度头盘间距动态测试要求。     

Readout characteristics of a non-circular aperture mounted on an optical head slider flying above a medium having sub-100-nm-long patterns

The near-field principle combined with thin-film gas-lubricated slider bearing technology is thought to be one of the most promising breakthroughs to overcome the difficult optical diffraction limit (or wavelength shortening limit), which governs traditional optical recording performance. In light of this, we have demonstrated high linear density (150 nm pattern length) and high speed 10 MHz readout signals using the combination of a tapered circular aperture and a planar lens mounted on a quartz slider, flying above a metal patterned medium. In order to further improve both the spatial resolution and signal-to-noise ratio of this device, it is essential to minimize the spacing and laser power throughput of an aperture. Also investigated was the effectiveness of a non-circular aperture, which has approximately triangular configuration in combination with polarized light in simultaneously improving spatial resolution and increasing signal output. In this paper, we confirmed the predicted effectiveness on more practical condition of both high speed and compactness of head construction using a sub-micrometer size non-circular aperture, which was mounted on a 1.5-mm-long miniaturized optical head slider, flying above a ROM medium having sub-100-nm-long chromium patterns. The influence of the electric-field direction of the incident light and aperture to medium spacing on the readout signal are carefully evaluated by flying the aperture at spacing down to less than 50 nm.     

Design of suspension and swing arm for improved shock resistance in the micro optical disk drives

One of the trends on information storage device is focused on the development of micro optical disk with optical flying head (OFH). The OFH in the small form factor ODD consists of optical slider, suspension, swing arm, and so on. In order for a slider with OFH to be successfully implemented in the system, the shock performance of the head-gimbal assembly should be guaranteed for mobile applications. We design development model of suspension and swing arm for improved shock resistance using topology optimization and shape optimization. The objective of the suspension design is to decrease the equivalent mass with increasing first torsional frequency. The objective of the swing arm design is mass reduction for reducing power consumption and fast access time. In this paper, we suggest a design method for the improvement of the dynamic performance of suspension and swing arm for the OFH considering shock characteristics.     

一种飞翼布局飞行平台FADS系统应用方案研究

对于一些高性能飞行器(如飞翼布局飞行器),仅采用安装在机头表面的测压孔的FADS系统方案.某些情况下不一定能够给出较为准确的飞行姿态数据;针对飞翼布局飞行平台对高精度迎角、侧滑角的依赖性.给出了一种采用安装于机头表面的测压孔和机翼前缘的测压孔相结合的FADS系统方案,推导了其空气动力学模型,并用BP神经网络拟合出了迎角和侧滑角的修正曲线,结果表明该方案能够满足系统精度的要求。     

基于GNSS的编队卫星相对定位模糊度解算性能分析

模糊度解算性能是影响卫星导航系统相对定位精度的决定性因素之一。针对编队卫星的星间相对定位需求,对影响模糊度解算成功率的主要因素及其作用进行了分析。通过多种场景下模糊度解算成功率的定量仿真,说明组合多种GNSS星座、增加观测频率的个数以及选取与星间基线长度相适应的电离层模型,均有利于提高模糊度解算的成功率,该结果对于相对定位性能的预测与编队卫星系统优化设计具有参考意义。