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3D positioning scheme exploiting nano-scale IR-UWB orthogonal pulses  [cached]
Kim Nammoon,Kim Youngok
Nanoscale Research Letters , 2011,
Abstract: In these days, the development of positioning technology for realizing ubiquitous environments has become one of the most important issues. The Global Positioning System (GPS) is a well-known positioning scheme, but it is not suitable for positioning in in-door/building environments because it is difficult to maintain line-of-sight condition between satellites and a GPS receiver. To such problem, various positioning methods such as RFID, WLAN, ZigBee, and Bluetooth have been developed for indoor positioning scheme. However, the majority of positioning schemes are focused on the two-dimension positioning even though three-dimension (3D) positioning information is more useful especially in indoor applications, such as smart space, U-health service, context aware service, etc. In this paper, a 3D positioning system based on mutually orthogonal nano-scale impulse radio ultra-wideband (IR-UWB) signals and cross array antenna is proposed. The proposed scheme uses nano-scale IR-UWB signals providing fine time resolution and high-resolution multiple signal specification algorithm for the time-of-arrival and the angle-of-arrival estimation. The performance is evaluated over various IEEE 802.15.4a channel models, and simulation results show the effectiveness of proposed scheme.
On the Positioning of Objects in Space  [PDF]
D. M. Snyder
Physics , 1999,
Abstract: The personal spatial structure of an observer is introduced as a central element in the positioning of objects in space. The link between a reference frame used by an observer and his personal spatial structure is discussed. Research on inversion or reversal of incoming light in psychology indicates that the personal spatial structure of an individual, as well as a reference frame that he uses, depends on the internal coordination of sensory stimuli and that the position of objects in space depends in part on psychological factors that affect one's personal spatial structure. Other research in psychology demonstrating the flexibility for an observer in determining the direction of up-down relative to a particular figure, and indeed relative to the entire surround, is also noted and supports the thesis that the observer plays a role in the positioning of objects in space.
Zigbee Based Wireless Sensor and Actuator Network for Service Robot Intelligent Space  [PDF]
Baoye Song, Xiao Lu, Xingzhen Bai
Wireless Sensor Network (WSN) , 2012, DOI: 10.4236/wsn.2012.410034
Abstract: Wireless sensor and actuator network is the key technology of service robot intelligent space. This paper is concerned with design and implementation of a ZigBee based wireless sensor and actuator network (hereinafter referred to as ZWSAN), which has been applied in our service robot intelligent space successfully. Firstly, a simplified ZigBee stack applied to ZWSAN is proposed and the primitives of the stack are illustrated after a short overview of ZigBee protocols. Then the implementation of hardware module and software stack is introduced in detail as well as several representative devices integrated into ZWSAN, including environmental sensors for environmental perception, home devices controllers for device control, embedded speech recognition module for speech control, IMU module for abnormal behaviors detection and laser robot control for service robot navigation. An application example is described to demonstrate how the devices in ZWSAN to provide service cooperatively. Finally, we conclude this paper and discuss the future directions.
3D Tracking and Positioning of Surgical Instruments in Virtual Surgery Simulation  [cached]
Zhaoliang Duan,Zhiyong Yuan,Xiangyun Liao,Weixin Si
Journal of Multimedia , 2011, DOI: 10.4304/jmm.6.6.502-509
Abstract: 3D tracking and positioning of surgical instruments is an indispensable part of virtual Surgery training system, because it is the unique interface for trainee to communicate with virtual environment. A suit of 3D tracking and positioning of surgical instruments based on stereoscopic vision is proposed. It can capture spatial movements of simulated surgical instrument in real time, and provide 6 degree of freedom information with the absolute error of less than 1 mm. The experimental results show that the 3D tracking and positioning of surgical instruments is highly accurate, easily operated, and inexpensive. Combining with force sensor and embedded acquisition device, this 3D tracking and positioning method can be used as a measurement platform of physical parameters to realize the measurement of soft tissue parameters.
Positioning a Node of Wireless Sensor Networks in 3 Dimensional Space  [PDF]
Wenhui NIE, Shiguang JU, Anrong XUE, Feng LI
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2009, DOI: 10.4236/ijcns.2009.26059
Abstract: To know the location of nodes is very important and valuable for wireless sensor networks (WSN), we present an improved positioning model (3D-PMWSN) to locate the nodes in WSN. In this model, grid in space is presented. When one tag is detected by a certain reader whose position is known, the tag’s position can be known through certain algorithm. The error estimation is given. Emulation shows that the positioning speed is relatively fast and positioning precision is relatively high.
Development of an Indoor Location Based Service Test Bed and Geographic Information System with a Wireless Sensor Network  [PDF]
Shau-Shiun Jan,Li-Ta Hsu,Wen-Ming Tsai
Sensors , 2010, DOI: 10.3390/s100402957
Abstract: In order to provide the seamless navigation and positioning services for indoor environments, an indoor location based service (LBS) test bed is developed to integrate the indoor positioning system and the indoor three-dimensional (3D) geographic information system (GIS). A wireless sensor network (WSN) is used in the developed indoor positioning system. Considering the power consumption, in this paper the ZigBee radio is used as the wireless protocol, and the received signal strength (RSS) fingerprinting positioning method is applied as the primary indoor positioning algorithm. The matching processes of the user location include the nearest neighbor (NN) algorithm, the K-weighted nearest neighbors (KWNN) algorithm, and the probabilistic approach. To enhance the positioning accuracy for the dynamic user, the particle filter is used to improve the positioning performance. As part of this research, a 3D indoor GIS is developed to be used with the indoor positioning system. This involved using the computer-aided design (CAD) software and the virtual reality markup language (VRML) to implement a prototype indoor LBS test bed. Thus, a rapid and practical procedure for constructing a 3D indoor GIS is proposed, and this GIS is easy to update and maintenance for users. The building of the Department of Aeronautics and Astronautics at National Cheng Kung University in Taiwan is used as an example to assess the performance of various algorithms for the indoor positioning system.
Relativistic Positioning System in Perturbed Space-time  [PDF]
Uro? Kosti?,Martin Horvat,Andreja Gomboc
Physics , 2015, DOI: 10.1088/0264-9381/32/21/215004
Abstract: We present a variant of a Global Navigation Satellite System called a Relativistic Positioning System (RPS), which is based on emission coordinates. We modelled the RPS dynamics in a space-time around Earth, described by a perturbed Schwarzschild metric, where we included the perturbations due to Earth multipoles (up to the 6th), the Moon, the Sun, Venus, Jupiter, solid tide, ocean tide, and Kerr rotation effect. The exchange of signals between the satellites and a user was calculated using a ray-tracing method in the Schwarzschild space-time. We find that positioning in a perturbed space-time is feasible and is highly accurate already with standard numerical procedures: the positioning algorithms used to transform between the emission and the Schwarzschild coordinates of the user are very accurate and time efficient -- on a laptop it takes 0.04 s to determine the user's spatial and time coordinates with a relative accuracy of $10^{-28}-10^{-26}$ and $10^{-32}-10^{-30}$, respectively.
Relativistic space-time positioning: principles and strategies  [PDF]
Angelo Tartaglia
Physics , 2012,
Abstract: Starting from the description of space-time as a curved four-dimensional manifold, null Gaussian coordinates systems as appropriate for relativistic positioning will be discussed. Different approaches and strategies will be reviewed, implementing the null coordinates with both continuous and pulsating electromagnetic signals. In particular, methods based on purely local measurements of proper time intervals between pulses will be expounded and the various possible sources of uncertainty will be analyzed. As sources of pulses both artificial and natural emitters will be considered. The latter will concentrate on either radio- or X ray-emitting pulsars, discussing advantages and drawbacks. As for artificial emitters, various solutions will be presented, from satellites orbiting the Earth to broadcasting devices carried both by spacecrafts and celestial bodies of the solar system. In general the accuracy of the positioning is expected to be limited, besides the instabilities and drift of the sources, by the precision of the local clock, but in any case in long journeys systematic cumulated errors will tend to become dominant. The problem can be kept under control properly using a high level of redundancy in the procedure for the calculation of the coordinates of the receiver and by mixing a number of different and complementary strategies. Finally various possibilities for doing fundamental physics experiments by means of space-time topography techniques will shortly be presented and discussed.
MOS-2: A Two-Dimension Space for Positioning MAS Organizational Models  [PDF]
Hosny Abbas,Samir Shaheen
Computer Science , 2015,
Abstract: The increased complexity and dynamism of present and future Multi-Agent Systems (MAS) enforce the need for considering both of their static (design-time) and the dynamic (run-time) aspects. A type of balance between the two aspects can definitely give better results related to system stability and adaptivity. MAS organization is the research area that is concerned with these issues and it is currently a very active and interesting research area. Designing a MAS with an initial organization and giving it the ability to dynamically reorganize to adapt the dynamic changes of its unpredictable and uncertain environment, is the feasible way to survive and to run effectively. Normally, MAS organization is tackled by what is called, MAS organizational models, which are concerned with the description (formally or informally) of the structural and dynamical aspects of agent organizations. This paper proposes a two-dimension space, called MOS-2, for positioning and assessing MAS organizational models based on two dimensions: their adopted engineering viewpoint (agent-centered or organization-centered) as the vertical dimension and the agents awareness/unawareness of the existence of the organizational level as the horizontal dimension. The MOS-2 space is applied for positioning a number of familiar organizational models. Its future trends and possible improvements are highlighted. They include the following, (1) adding Time as a dimension, (2) increasing the considered dimensions, (3) providing a quantitative approach for positioning MAS organizational models.
3D DOPs for Positioning Applications Using Range Measurements  [PDF]
Binghao Li, Andrew G. Dempster, Jian Wang
Wireless Sensor Network (WSN) , 2011, DOI: 10.4236/wsn.2011.310037
Abstract: For terrestrial positioning, some applications require three dimensional coordinates. The Dilution of precisions (DOPs) for position systems using range measurement are reviewed and the average values of DOPs for different deployments of base station geometries are examined. It is shown that to obtain the lowest DOPs, the base stations for different types of positioning systems need to be deployed differently. Changing the N-sided regular polygon to an (N - 1)-sided polygon with one base station in the centre of the polygon can decrease the value of DOP in general for a pseudorange time of arrival (TOA) system but not for an absolute range TOA system. The height of the base station in the centre can also change the DOP significantly. The finding can be used to optimize the deployment of the base stations for range measurement positioning systems.
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