基于DirectX地图编辑器的研究与设计

游戏开发引擎中地图编辑器的设计对于能否快捷、高效地实现高质量游戏地图至关重要.程序在.NET环境下设计,应用DirectX技术实现了游戏的地图编辑器.本文主要介绍了DirectX技术,详细论述了游戏地图编辑器主界面的设计及动画等技术的实现,并且对遮挡及半透效果的实现方法进行改进,设计了组合对象的复制、粘贴、移动技术.     

基于免疫自适应遗传算法的机器人栅格地图融合

融合各机器人独自创建的环境地图,实现信息共享,是提高分布式多移动机器人系统环境探索效率的关键.研究了在没有公共参考坐标系及机器人相对位置信息未知情况下的栅格地图融合问题,提出了一种基十免疫自适应遗传算法的栅格地图融合方法,该算法把反映两个栅格地图重叠区域相异程度的优化函数作为抗原,每个可能的平移、旋转平面转换对应一个抗体.仿真结果表明了该算法可以较快的收敛速度和较强的全局搜索能力,搜索到两个栅格地图的最佳重叠区域,实现地图融合.     

多机器人地图融合方法研究

多机器人建图是实现机器人自主导航,完成复杂智能任务的关键.其中如何将不同机器人采集的数据融合到全局地图中,成了多机器人建图中的一个核心问题.文中采用独立探索、集中建图的探索策略,提出一种基于改进差异进化算法的多机器人概率栅格地图的融合.该算法在地图相似度的概念基础上,建立相异度函数,利用改进的进化算法搜索策略快速地搜索各局部地图之间的最大重叠部分,实现了多机器人系统栅格地图的融合,有效的解决了相对位置未知情况下的地图创建问题.通过实验验证了该方法正确、可行.     

基于地图的移动机器人自定位与导航系统

针对地图已知情况下的移动机器人大范围导航问题,研制了一个由地图编辑器模块、地图匹配与定位模块以及多层递阶规划模块三部分组成的移动机器人导航系统．地图编辑器负责导航地图的编辑;地图匹配与定位模块利用里程计和激光雷达数据实现基于地图匹配的自定位;多层递阶规划模块将基于拓扑地图的全局规划、基于栅格地图的局部规划和底层的行为控制功能有机结合．通过室内定位和大范围导航实验评估了本系统的有效性和准确性．     

多机器人协同的SLAM算法研究

针对传统的室内多机器人SLAM算法存在探索任务分配灵活低,重叠度高,导致地图融合和建图精度不高的问题。设计一个基于PSO算法的多机器人协同建图与路径规划系统。首先,采用SLAM系统中的Gmapping算法作为基础算法,加入PSO算法将地图融合问题转化为最优求解问题,即找到两个地图重叠度最高的转换矩阵,实现地图融合和多机器人协同建图。结果表明,相同室内环境下,单机器人的平均探索时间为216 s,探索覆盖率为73..38%;而双机器人的平均探索时间仅为47 s,比单机器人的探索时间低了169 s;且双机器人的探索覆盖率为99.69%,比单机器人高出了26.31%。由此说明,双机器人的探索效率和探索覆盖率更高。对比于现有的EKF-CSLAM算法和基于因子图地图融合算法,本算法的建图精度高达99.75%。地图融合和建图精度明显更佳,进一步说明提出的融合算法可提升多机器人室内环境协同建图的效率和鲁棒性。     

全自主机器人足球系统的全局地图构建研究

研究和讨论了如何通过多机器人的协作,实现全局地图的构建．在单个机器人通过自身携带的多传感器进行局部地图构建的基础上,研究了前向单目视觉传感器的建模方法,在此观测模型的基础上,用极大似然融合算法对球的位置信息进行融合,而对于多机器人返回的对方机器人位置信息,使用基于密度的空间聚类算法（DBSCAN）进行信息融合,从而实现全局地图构建．实验结果表明,通过多机器人的协作,可以准确地构建出全局地图,弥补了单个机器人自身传感器的有限感知范围,本文研究的方法完全满足全自主机器人足球比赛中动态环境地图构建的需要．     

基于多传感信息融合的儿童教育机器人研究

针对当前儿童教育机器人地图构建、定位和路径规划效果不佳的问题,提出基于运动模型和观测模型融合的儿童教育机器人。通过改进RBPF-SLAM定位算法,实现地图构建和准确定位,利用混合路径规划算法实现全局寻优。实验结果表明,改进的RBPF-SLAM定位算法计算结果更接近于真实状态值,比改进前的算法更精确,算法性能更佳。且提出的混合路径规划算法可在复杂环境下找出最佳路径,由此可知,巡检机器人可实现地图构建和路径规划。     

自绘2D存档游戏的设计与实现

基于SQL Server2005数据库和Win32 Application,利用VC＋＋6．0设计开发一款自绘2D存档游戏,并给出核心算法。利用地图编辑器与数据库进行交互,用相对坐标实现画面的流畅移动,使用双缓冲区的方法解决画图时出现的闪烁问题。     

基于信息增益一致性的多机器人地图融合算法

针对多机器人协同SLAM(同步定位与地图构建)的地图融合中,由于通信距离受限或网络拓扑变化造成信息缺失、从而影响全局地图构建的问题,提出一种基于信息增益一致性原理的动态地图融合算法.该算法是完全分布式的,且不依赖于任何特殊的机器人通信网络结构.该算法利用机器人所测局部地图的历史数据和当前数据之间的新增信息,使每个机器人都能同步地获取一致的、最新的全局地图.在有限的网络连接条件下,所提出的地图融合算法能够通过渐近收敛的方式获得准确的全局地图.在每一次迭代中,每个机器人得到的全局地图都是无偏的.在实验中通过实际环境的RGB-D(彩色-深度)数据验证了算法的有效性.     

多机器人同步定位与地图构建的地图融合算法的改进

本文主要研究了多机器人同步定位与地图构建(SLAM)的地图实时融合问题.在本文中提出一种混合的SLAM算法(HybridSLAM)算法,可以同时观测和更新多个路标,并根据FastSLAM2.0思想利用选取的最准确的路标观测值来修正机器人位姿.然后,在改进HybridSLAM算法基础上,进一步提出一种改进的多机器人HybridSLAM算法(MR–IHybridSLAM).每个机器人在不同初始位置运行IHybridSLAM算法构建子地图,并将子地图信息实时发送到同一工作站中.根据卡尔曼滤波(KF)原理将每个机器人构建的子地图融合成全局地图.最后,通过仿真实验构建多机器人融合的特征地图并与单一机器人快速的SLAM算法(FastSLAM)和HybridSLAM算法构建的地图进行误差对比,进一步来验证该算法的准确性、快速性和可行性.     

Solid Texturing of Soft Objects

Since the shape of a soft object changes in response to its surroundings, it is difficult to give a single position in space as the location of the object. Indeed objects can and do break dynamically into subobjects. This means that you cannot map a solid texture onto such an object simply by using a function of the space coordinates. We have taken a different approach. Our soft objects are modeled as the volume enclosed by an isosurf ace of a field calculated from a set of key points. For each key point, we describe an abstract texture space. Any point on the surface of an object has, associated with each key point, a position in this space and a field contribution. A vector sum of these positions, weighted by the field contributions, is used to select a surface specification from the texture space. Textures mapped with this process retain their consistency during distortion and metamorphoses of objects, permitting a great variety of animation effects.     

Inferring transforms [computer graphics]

In simple two-dimensional texture mapping you take a 2D image and render it on the screen after some transformation or distortion. To accomplish this you will need to take each [X, Y] location on the screen and calculate a [U, V] texture coordinate to place there. A particularly common transformation is: U=(aX+bY+c)/(gX+hY+j), V=(dX+eY+f)/(gX+hY+j). By picking the proper values for the coefficients a…j, we can fly the 2D texture around to an arbitrary position, orientation, and perspective projection on the screen. You can, in fact, generate the coefficients by a concatenation of 3D rotation, translation, scale, and perspective matrices. However, the author discusses a more direct approach to finding a…j. It turns out that the 2D-to-2D mapping is completely specified if you give four arbitrary points in screen space and the four arbitrary points in texture space they must map to. The only restriction is that no three of the input or output points may be collinear. This method of transformation specification proves useful, for example, in taking flat objects digitized in perspective and processing them into orthographic views     

在Maplnfo电子地图中搜寻最短路径的实现

根据Maplnfo电子地图的特点，本文介绍了如何从电子地图中提取出交通道路及道路交汇点信息，并将其抽象成图，选择合适的结构进行存储．然后运用Dijkstra最短路径算法求解最短路径，根据求解结果在电子地图上绘制线路图。     

基于Supermap Objects的地图标绘系统的设计实现

地图标绘指在地图背景上标绘各种具有空间特征的事、物的分布状态或行动部署。而基于一种GIS组件实现地图标绘,是目前电子地图发展的需要。本文从用户需求出发,给出了系统实现的界面功能、数据组织与核心算法等设计思想,详细阐述了系统的软件结构,软件实现方法与过程。     

基于Supermap Objects的地图标绘系统的设计实现

地图标绘指在地图背景上标绘各种具有空间特征的事、物的分布状态或行动部署。而基于一种GIS组件实现地图标绘,是目前电子地图发展的需要。本文从用户需求出发,给出了系统实现的界面功能、数据组织与核心算法等设计思想,详细阐述了系统的软件结构．软件实现方法与过程。     

Real-Time Updating of 2D Map for Autonomous Robot Locomotion Based on Distinction Between Static and Semi-Static Objects

Autonomous mobile robots are increasingly being used in complex 2D environments such as factories, warehouses, and offices. For such environments, we propose a real-time technique for updating an environmental map for a robot’s self-localization using a bearing-range sensor in situations where a basis map can be preliminarily prepared. These environments include many semi-static objects such as cardboard boxes, and the locations of these objects change frequently. Therefore, the self-localization needs to reflect the changes in both the existence and position of semi-static objects in the map in real-time. However, if the robot uses a traditional technique that updates all objects and if it keeps updating the map for a long period, static objects such as walls will move slightly on the map due to errors of both measurement and self-localization, and the map will be distorted. Therefore, our technique distinguishes between static and semi-static objects on the map, and it defines the changeability of the occupancy probability of every spatial grid in order to update the map without changing the occupancy probabilities of grids around static objects. By doing so, we prevented the map from being distorted. In addition, by estimating the grids’ statuses during two observations of the same grids and by changing the probabilities of the objects’ fixedness based on the statuses, our technique can robustly distinguish the objects on the map even if the timing of observing grids is irregular.     

VRML adds a new dimension to Web browsing

One of the most exciting developments on the World Wide Web is the emergence of the Virtual Reality Modeling Language (VRML). While true cyberspace is quite a few years in the future, VRML (often pronounced `vermal') does offer some tantalizing previews of what is to come. VRML is away of compactly describing 3D objects and scenes, based on Silicon Graphics' Open Inventor file format. It lets authors embed links in and apply textures to objects. Authors can also set the levels of detail displayed to approximate real life, where objects in the distance seem less detailed than closer objects. VRML files can be smaller than fully rendered worlds because the format merely specifies what the client machine should render. In other words, your machine receives the VRML instructions, then renders the scene itself. The speed of your machine's graphics capabilities can sometimes have as much influence as the speed of your Internet connection on how long you wait to view files. The type of computer you have will also affect the quality of the graphics     

GPS/MM车载导航系统的研究与实现

车辆导航系统的一项重要功能是将GPS的定位数据在电子地图上精确显示。由于坐标系的差异,需进行坐标转换。定位数据因多种原因存在误差,因此需要合适的地图匹配算法来提高定位精度。依据道路网络的拓扑性,以及自适应加权匹配因子的计算,提出了一种实用的地图匹配算法,并在实践中得到了验证,能够提高定位数据的精度和可靠性。     

Tell less, say more: the power of implicitness

Implicitness is a very practical feature of OO development, as distinctive as anything that is routinely considered part of the definition. It is the constant refusal to say more than what we strictly need to say. The double refusal (refusal to close, refusal to assert completeness) requires some intellectual audacity, but yields a productive development process. In the end, what resolves the contradiction is the release of the software. The release process (the process of closing what was until now open) is the process of equating each type with the Cartesian product of its properties. So when everything has been said, the objects are indeed what they have. But only at the end. Until then, you always leave room for more properties. Everything is open until officially closed; and by telling less now you retain the possibility of saying more later     

带有位置修正的环境映射

由于没有考虑物体表面位置的影响,基本的环境映射技术在反射计算中存在一定的几何偏差,而且无法实现视差效果。本文通过引入位置修正对该技术进行了改进。首先,利用距离图来保存环境表面位置信息;然后,分两种情况利用距离图对环境贴图的查询矢量进行修正,以减小反射计算的几何偏差;最后,通过分层渲染的方法处理包含多个环境物体的场景。实验结果表明,位置修正的引入提高了环境映射光照计算的准确性;并且能获得因物体互相遮挡而产生的视差效果。