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31.
GNSS系统接收机自主完好性监测算法   总被引:2,自引:1,他引:1       下载免费PDF全文
提出一种适用于多星座情况的接收机自主完好性监测算法——基于完好性指标动态分配的完好性监测算法。该算法比传统算法更能适应多星座情况下不同星座观测量属性的差异,其可用性比传统算法提高2%~3%。在多星座和双频情况下,利用该算法分析完好性监测的性能,结果表明,该算法在LPV-200完好性要求下是适用的。  相似文献   
32.
随着众多科技成果产业化实践,路灯种类数量猛增;其中,嵌入式路灯凭借安装简便、外观一体化强、整体美感突出等诸多优点,被广大使用者所推崇;但是,传统嵌入式路灯监控系统存在多组灯系启动、关闭、维护、巡查困难,故障排除时效长、人力资源开销大的弊端;针对问题产生根源,提出针对嵌入式路灯远程监控系统的设计研究方法;采用高集成低频无线对接模块,对每个灯组进行编码桥接,采用网络大数据FGT-J5i处理单元,对灯组进行网络远程智能化监控,同时,搭建配套智能监控平台;通过仿真实验测试证明,提出针对嵌入式路灯远程监控系统的设计,满足日常使用与远程监控要求。  相似文献   
33.
This paper presents a novel approach to the design of globally asymptotically stable (GAS) position and velocity filters for Autonomous Underwater Vehicles (AUVs) based directly on the sensor readings of an Ultra-short Baseline (USBL) acoustic array system and a Doppler Velocity Log (DVL). The proposed methodology is based on an equivalent linear time-varying (LTV) system that fully captures the dynamics of the nonlinear system, allowing for the use of powerful linear system analysis and filtering design tools that yield GAS filter error dynamics. Numerical results using Monte Carlo simulations and comparison to the Bayesian Cramér Rao Bound (BCRB) reveal that the performance of the proposed filter is tight to this theoretical estimation error lower bound. In comparison with other approaches, the present solution achieves the same level of performance of the Extended Kalman Filter (EKF), which does not offer GAS guarantees, and outperforms other classical filtering approaches designed in inertial coordinates instead of the body-fixed coordinate frame.  相似文献   
34.
Tap-n-drag is a popular navigation method for small touch-screen interfaces. When an information space is too large compared to the touch-screen size, navigating the information space using tap-n-drag requires too many drags, resulting in poor usability such as long navigation time or fatigue. In this study, the effect of control-to-display gain on the usability of tap-n-drag was experimentally investigated to determine whether increasing the control-to-display gain can resolve this problem. The effect of movement direction of the information space relative to the drag direction was also investigated (push background vs. push viewport). In experiments, increasing control-to-display gain seemed to increase the usability of tap-n-drag, but excessively large gain seemed to have the opposite effect on some measures such as task completion time, ease of use and overall preference; as a result these measures-vs.-GAIN curves were U-shaped or inverted-U-shaped. Overall, both task completion time and number of touches required to locate a target were lower when using push viewport than when using push background, except at GAIN = 1.

Relevance to industry

The results of this study can be used to enhance the usability of tap-n-drag and other navigation methods in small touch-screen devices when users navigate a large information space.  相似文献   
35.
郑莹 《工业控制计算机》2011,24(12):104-104,106
设计的目的是通过传感器监测每个路口的车辆驶入和驶出的流量,利用单片机的计数器来记录传感器产生的车流脉冲,并通过GSM模块通过无线通信的方式,将系统中采集的车流量数据,沿着车辆通行的方向,按照相邻原则进行传递,让信号灯与其邻近的信号灯进行协调,实现车流量对交通信号灯的智能控制。  相似文献   
36.
介绍了一种由8031单片机控制的循环灯,说明了其硬件和软件的实现方法。  相似文献   
37.
There is huge diversity among navigation and path-planning problems in the real world because of the enormous number and great variety of assumptions about the environments, constraints, and tasks imposed on a robot. To deal with this diversity, we propose a new solution to the path-planning and navigation of a mobile robot. In our approach, we formulated the following two problems at each time-step as discrete optimization problems: (1) estimation of a robot's location, and (2) action decision. For the first problem, we minimize an objective function that includes a data term, a constraint term, and a prediction term. This approach is an approximation of Markov localization. For the second problem, we define and minimize another objective function that includes a goal term, a smoothness term, and a collision term. Simulation results show the effectiveness of our approach. This work was presented in part at the Fifth International Symposium on Artificial Life and Robotics, Oita, Japan, January 26–28, 2000  相似文献   
38.
建立适合于车载导航系统的路网数据是车载导航系统的关键。本文描述了如何表达真实世界的交通要素,并结合实际情况给出数据模型。  相似文献   
39.
40.
Autonomous and mobile robots are being expected to provide various services in human living environments. However, many problems remain to be solved in the development of autonomous robots that can work like humans. When a robot moves, it is important that it be able to have self-localization abilities and recognize obstacles. For a human, the present location can be correctly checked through a comparison between memorized information assuming, it is correct, and the present situation. In addition, the distance to an object and the perception of its size can be estimated by a sense of distance based on memory or experience. Therefore, the environment for robotic activity assumed in this study was a finite-space such as a family room, an office, or a hospital room. Because an accurate estimation of position is important to the success of a robot, we have developed a navigation system with self-localization ability which uses only a CCD camera that can detect whether the robot is moving accurately in a room or corridor. This article describes how this system has been implemented and tested with our developed robot.  相似文献   
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