一种多模式全向移动机器人攀爬楼梯的步态

针对移动机器人在户外运动中所遇到的台阶、楼梯等复杂地形,设计了一种可攀爬楼梯的多模式全向移动机器人。通过切换运动模态,该机器人既能像传统移动机器人一样快速移动,又具备了足式机器人的越障能力。首先,分析并构建了多模式全向移动机器人的运动学模型;其次,研究了该机器人越障能力和质心位置之间的关系并计算了该机器人可以翻越台阶的...     

基于ADAMS的四轮驱动移动机器人越障预测

针对移动机器人越障问题,构建预测模型。对四轮驱动移动机器人在三类不同障碍物条件下的越障情况进行了分析。运用虚拟样机动力学仿真软件ADAMS构建四轮驱动移动机器人参数化模型,并构建矩形障碍、广义障碍和斜坡障碍的参数化模型,从而组成参数化预测平台。通过该平台可以在三维计算机仿真环境下观察并预测移动机器人在矩形障碍、广义障碍和斜坡障碍等不同障碍条件下的越障能力,结合绘制的速度、加速度及驱动转矩等曲线可以分析越障过程中可能出现的问题。     

智能移动机器人的研究

随着社会的发展和科学技术的不断进步,人们对智能移动机器人的研究也不断深入.本文在介绍了常见智能移动机器人的基本组成的基础上,提出了一种能够应用于智能移动机器人的越障机构,并阐述了其工作原理.本文还对智能移动机器人未来发展动向进行了预测.     

地面移动机器人越障动力学建模与分析

对采用轮—腿—履带复合型移动机构的地面移动机器人进行了研究,首先分别描述了机器人采用腿—履带、轮—腿—履带两种方式的越障过程,进而对腿—履带复合越障过程进行了动力学建模,分析了电机驱动力矩与机器人速度及障碍物高度等之间的关系,为确定机器人的复杂环境适应能力提供理论依据.     

基于ADAMS的输电线路移动机器人越障仿真

移动越障机构是输电线路移动机器人的基础,也是目前制约线路移动机器人发展的技术障碍之一.采用SolidWorks三维建模软件和ADAMS动力学仿真分析软件在虚拟环境中建立双臂移动机器人的仿真模型.通过避障路径规划生成运动仿真数据,在ADAMS虚拟环境中实现双臂移动机器人的稳定越障.仿真结果表明:双臂移动机器人的两臂交错滑移结构设计能够满足行走要求,且避障路径规划方法可行,仿真数据可为下一步双臂移动机器人物理样机的研制提供理论参考.     

地形自适应救援机器人设计

为实现机器人在复杂环境中快速灵活的运动要求,该文设计了一种轮履复合式快速移动机器人,并针对其3种不同运动模式进行分析.利用智能辅助控制策略,机器人运行中可根据地形不同而采取不同的运动模式,简化了操作难度.机器人采用基于ADXRS610的角度测量单元,STM32F103单片机实时处理角度变化情况来不断监测机器人姿态,在复杂地形中通过调整机器人结构使机器人保持最佳驱动状态.通过不断地调试,最终实现机器人地形自适应的要求,具有运动灵活、操作简单、越障能力强、功耗低的特点.     

机器人俯仰关节能耗特性分析

以降低架空线移动机器人能耗为目标,从结构设计角度出发提出一种基于平行四边形机构的机器人俯仰关节,由单电机配合柔索驱动。首先,在考虑摩擦因素的情况下进行了关节受力及能耗分析,分别给出本文关节与传统俯仰关节的能耗计算方法。再分别就多单元串联式机器人俯仰运动、以及架空线移动机器人越障运动的能耗特性,进行了本文关节和传统俯仰关...     

履带腿式非结构环境移动机器人特性分析

针对非结构环境的特点,提出一种适用于非结构环境的新型履带腿移动机器人.这种移动机器人结构简洁,实用,具有很好的环境适应能力.本文主要分析该移动机器人在非结构环境下的斜坡行走、越障、跨沟、阶梯地形行走、自动复位等功能.􀁱 􀁽     

一种新型轮腿式移动机器人的参数设计与实验研究

面向复杂未知环境探索作业对移动机器人的重大重要需求,借鉴3轮辐型轮腿越障能力强和弧形轮腿缓冲减振好的优势,提出一种新型轮腿式移动机器人.以攀爬楼梯为越障任务和设计目标,从静力学角度分析机器人轮腿与楼梯台阶不产生滑移的条件,得出机器人可跨越楼梯台阶的必要条件.从几何学角度规划一种机器人高效攀爬楼梯的轨迹,据此完成机器人轮腿结构的参数设计,并研究轮腿结构参数对机器人抗冲击能力和续航能力的影响规律.最后,通过软件仿真和爬楼梯实验验证上述工作的可行性和有效性.     

基于粒子滤波的欠驱动移动机器人多目标点跟踪控制

针对欠驱动移动机器人的多目标点跟踪问题,提出了一种基于粒子滤波的高精度跟踪控制方法;具体地,在考虑移动机器人采样噪声的情况下,首先利用粒子滤波对移动机器人的位置信息进行处理,得到精准可靠的移动机器人状态信息;在此基础上,根据欠驱动移动机器人的运动学模型以及目标点的分布状况,设计基于反馈控制的多目标点跟踪控制方法;相对于传统的欠驱动移动机器人目标点跟踪控制算法,改进了该控制方法中增益参数的约束条件,有效避免了移动机器人在接近目标点时产生的奇异现象,有效提高了移动机器人对目标点的跟踪精度;此外,分析了该目标点跟踪控制系统的稳定性,并通过数值仿真验证了所提方法的可行性与有效性.     

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

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.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

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。