基于模型的预警无人机飞控系统开发与验证

为应对城市低空预警任务对固定翼无人机飞控系统自主飞行需求,采用基于模型设计方法完成无人机飞控系统开发与验证;开发过程中以飞控算法模型为中心,逐级开展飞控算法模型设计与数学仿真、算法快速原型验证以及飞控系统硬件产品实现;飞控算法模型在Matlab/Simulink平台中完成了构建及数学仿真验证,结合Higale系统提供的实时仿真环境完成算法快速原型验证,基于代码自动生成方式将算法模型自动转换为可在DSP中运行的实时代码,下载到飞控计算机中,进行硬件在回路仿真验证,并进一步进行整机地面验证;经过实践,所提出的飞控系统开发与验证流程可以将系统设计中存在的问题缺陷在开发早期暴露出来并及时修正,保证了系统研制进度、成本和品质。     

基于ARM小型直升机飞控系统设计与实现

介绍基于ARM7某型直升机自主飞行控制系统的设计及实现;先简要说明飞控系统的ARM硬件实现和软件架构,然后在该INS基础上,设计并实现扩展卡尔曼滤波器,融合INS数据以准确获得飞机姿态角;进一步设计实现基于位置和速度跟踪的飞行控制器,通过对飞机位置和速度的规划,实现飞机的多任务、长距离飞行任务;地面测试和试飞表明该飞控系统达到设计的要求,性能稳定。     

一种飞控系统信号源仿真设备的设计与实现

设计和研制了一种飞控系统信号源仿真设备,用于模拟飞机运动参数传感器分系统、电子飞行仪表系统等飞控系统信号源,旨在替代实物满足飞机飞控系统在地面静态综合试验和动态半物理仿真试验中对相应设备的需求。介绍了仿真设备需求、硬件配置、软件设计和维修性设计。     

直升机神经网络模型辨识研究

研究直升机飞控系统的控制问题,直升机是强耦合的非线性系统,直升机的模型的建立是研究整个飞控系统的基础.为改善飞行姿态误差,提高稳定性,建立其较为精确的动力学模型对于设计、验证飞行控制系统具有重要意义.根据直升机动力学方程的形式,建立了一种基于BP神经网络的非线性辨识模型,利用典型状态下的试飞数据作为样本,采用LM优化学习算法对神经网络进行训练,并用其他飞行状态的数据对模型进行验证.计算结果表明,证明所建立的神经网络模型具有较好的拟合精度与泛化能力,能够较好地反映直升机的动态特性,并为设计提供依据.     

直升机光传操纵地面物理仿真平台的开发

该文基于某型武装直升机控制增稳飞控系统，建立了直升机光传操纵地面物理仿真平台，着重开发了两种典型的光传技术。并叙述了仿真平台的结构配置及主要组成部件开发实现。实现了具有人机交互功能的直升机光传操纵可视化仿真，并通过光传与电传的特性对比验证了两种光传技术的有效性。从而为我国直升机光传系统的实现，提供了有效的地面开发平台。     

某型直升机半物理仿真系统的设计

飞控计算机是现代直升机控制的不可缺少的部分。研制功能完善的高性能飞控计算机是直升机发展的重要一步;在飞控计算机应用到直升机上之前,需要对其进行较为全面的仿真测试;文章结合飞行控制律的设计,开发了用于对飞控计算机进行全面测试的半物理仿真系统;主要完成了模型的建立和仿真,研制了基于嵌入式操作系统VxWorks及仿真工具软件MATLAB的主仿真系统并进行了调试;通过对其开环和闭环的调试以及仿真结果的分析表明,该系统对发送的飞机姿态信息能够进行实时显示和处理。满足飞行品质技术指标要求。半物理仿真结果可真实可靠的反映直升机的飞行过程。     

8098单片机在转台控制系统中的应用

转台是航空航天工业中重要的地面仿真设备。本文利用８０９８的资源，设计了８０９８单片机系统的硬件和软件，应用于三轴液压转台控制系统中，从而提高了转台的动态特性和静态精度，并增加了转台位置数显功能。     

基于摩擦补偿观测器的转台控制器设计

以单轴转台为对象,设计PID控制器.通过硬件电路设计、转台模型辩识、控制律设计以及系统软件编制,构建了转速控制系统,实现了对转台的速度控制;针对转台低速存在的滞滑现象,建立带摩擦模型的转台系统,提出了基于摩擦补偿观测器的滞滑现象的抑制方法;试验结果表明,控制系统运行稳定,摩擦补偿效果令人满意,满足了给定的设计指标,证明了所用方案的可行性和有效性.     

基于故障检测的无人直升机作动器重构控制

提高直升机电传飞控系统的可靠性是保证无人直升机智能化的霞要方面,文中针对单旋翼加尾桨构型无人直升机的作动器故障,研究了倾斜器故障重构控制方法,重点提出了作动器的故障检测方法,运用模型的故障诊断技术,设计了基于倾斜器故障重构控制的无人直升机作动器故障时的重构控制策略,经过试飞证明此方法为作动器故障时的直升机安全飞行提供了一种可行方案,达到了设计目的.     

基于功能模型的飞控系统安全性设计技术研究

为了确保飞控系统的安全可靠,提出一种基于功能模型的飞控系统安全性设计方法.首先,以需求为牵引,结合飞机的使用场景和性能,实现飞控系统的功能设计;然后,基于安全性设计理念,从系统功能的失效出发实现系统架构的余度设计,同时针对传统方法仅关注系统本身的故障组合分析,存在局限性、滞后性等问题,提出了基于网络化方法开展飞控系统故障推演的功能模型方法;最后,通过应用结果表明了本文所提方法的有效性和可行性.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.