• Title, Summary, Keyword: three dimensional tracking

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Three-dimensional trajectory tracking for underactuated AUVs with bio-inspired velocity regulation

  • Zhou, Jiajia;Ye, Dingqi;Zhao, Junpeng;He, Dongxu
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.10 no.3
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    • pp.282-293
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    • 2018
  • This paper attempts to address the motion parameter skip problem associated with three-dimensional trajectory tracking of an underactuated Autonomous Underwater Vehicle (AUV) using backstepping-based control, due to the unsmoothness of tracking trajectory. Through kinematics concepts, a three-dimensional dynamic velocity regulation controller is derived. This controller makes use of the surge and angular velocity errors with bio-inspired models and backstepping techniques. It overcomes the frequently occurring problem of parameter skip at inflection point existing in backstepping tracking control method and increases system robustness. Moreover, the proposed method can effectively avoid the singularity problem in backstepping control of virtual velocity error. The control system is proved to be uniformly ultimately bounded using Lyapunov stability theory. Simulation results illustrate the effectiveness and efficiency of the developed controller, which can realize accurate three-dimensional trajectory tracking for an underactuated AUV with constant external disturbances.

A system for three-dimensional gaze fixation analysis using eye tracking glasses

  • Takahashi, Ryo;Suzuki, Hiromasa;Chew, Jouh Yeong;Ohtake, Yutaka;Nagai, Yukie;Ohtomi, Koichi
    • Journal of Computational Design and Engineering
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    • v.5 no.4
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    • pp.449-457
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    • 2018
  • Eye tracking is a technology that has quickly become a commonplace tool for evaluating package and webpage design. In such design processes, static two-dimensional images are shown on a computer screen while a subject's gaze where he or she looks is measured via an eye tracking device. The collected gaze fixation data are then visualized and analyzed via gaze plots and heat maps. Such evaluations using two-dimensional images are often too limited to analyze gaze on three-dimensional physical objects such as products because users look at them not from a single point of view but rather from various angles. Therefore in this study we propose methods for collecting gaze fixation data for a three-dimensional model of a given product and visualizing corresponding gaze plots and heat maps also in three dimensions. To achieve our goals, we used a wearable eye-tracking device, i.e., eye-tracking glasses. Further, we implemented a prototype system to demonstrate its advantages in comparison with twodimensional gaze fixation methods.

Particle tracking algorithm for the Lagrangian-Eulerian finite element method

  • 석희준
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.97-100
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    • 2004
  • Multivariate Newton Raphson method is developed to perform the particle tracking in the three dimensional area using four objective functions. In this method, three variables are solved to compute target point and actual and real tracking time. The simulated pathlines in various types of three dimensional elements are well matched with exact pathline.

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Design and Implementation of Real-time three dimensional Tracking system of gazing point (삼차원 응시 위치의 실 시간 추적 시스템 구현)

  • 김재한
    • Proceedings of the IEEK Conference
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    • pp.2605-2608
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    • 2003
  • This paper presents design and implementation methods of the real-time three dimensional tracking system of the gazing point. The proposed method is based on three dimensional data processing of eye images in the 3D world coordinates. The system hardware consists of two conventional CCD cameras for acquisition of stereoscopic image and computer for processing. And in this paper, the advantages of the proposed algorithm and test results ate described.

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NUMERICAL SIMULATION OF MULTIPHASE FLOW USING LEVEL CONTOUR RECONSTRUCTION METHOD (Level Contour Reconstruction 방법을 이용한 다상유동 수치해석)

  • Shin, Seung-Won
    • 한국전산유체공학회:학술대회논문집
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    • pp.193-200
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    • 2009
  • Recently, there have been efforts to construct hybrids among the existing methodologies for multiphase flow such as VOF, Level Set, and Front Tracking with the intention of facilitating simulations of general three-dimensional problems. As one of the hybrid method, we have developed the Level Contour Reconstruction Method (LCRM) for general three-dimensional multiphase flows including phase change. The main idea was focused on simplicity and a robust algorithm especially for the three-dimensional case. It combines characteristics of both Front Tracking and Level Set methods. While retaining an explicitly tracked interface using interfacial elements, the calculation of a vector distance function plays a crucial role in the periodic reconstruction of the interface elements in the LCRM method to maintain excellent mass conservation and interface fidelity. In addition, compact curvature formulation is incorporated for the calculation of the surface tension force thereby reducing parasitic currents to a negligible level.

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Implementation of eye-controlled mouse by real-time tracking of the three dimensional eye-gazing point (3차원 시선 추적에 의한 시각 제어 마우스 구현 연구)

  • Kim Jae-Han
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • pp.209-212
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    • 2006
  • This paper presents design and implementation methods of the eye-controlled mouse using the real-time tracking of the three dimensional gazing point. The proposed method is based on three dimensional data processing of eye images in the 3D world coordinates. The system hardware consists of two conventional CCD cameras for acquisition of stereoscopic image and computer for processing. And in this paper, the advantages of the proposed algorithm and test results are described.

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Location-aware visualization of VRML models in indoor location tracking system

  • Yang, Chi-Shian;Chung, Wan-Young
    • Journal of Sensor Science and Technology
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    • v.16 no.3
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    • pp.220-228
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    • 2007
  • For many applications particularly in navigation system, a three-dimensional representation improves the usability of information. This paper introduces 3D Graphical User Interface (GUI) of indoor location tracking system, 3D Navigation View. The application provides users a 3D visualization of the indoor environments they are exploring, synchronized with the physical world through spatial information obtained from indoor location tracking system. It adopts widely used Virtual Reality Modeling Language (VRML) to construct, represent, distribute and render 3D world of indoor environments over Internet. Java, an all-purpose programming language is integrated to comprehend spatial information received from indoor location tracking system. Both are connected through an interface called External Authoring Interface (EAI) provided by VRML. Via EAI, Java is given the authority to access and manipulate the 3D objects inside the 3D world that facilitates the indication of user's position and viewpoint in the constructed virtual indoor environments periodically.

A local-global scheme for tracking crack path in three-dimensional solids

  • Manzoli, O.L.;Claro, G.K.S.;Rodrigues, E.A.;Lopes, J.A. Jr.
    • Computers and Concrete
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    • v.12 no.3
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    • pp.261-283
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    • 2013
  • This paper aims to contribute to the three-dimensional generalization of numerical prediction of crack propagation through the formulation of finite elements with embedded discontinuities. The analysis of crack propagation in two-dimensional problems yields lines of discontinuity that can be tracked in a relatively simple way through the sequential construction of straight line segments oriented according to the direction of failure within each finite element in the solid. In three-dimensional analysis, the construction of the discontinuity path is more complex because it requires the creation of plane surfaces within each element, which must be continuous between the elements. In the method proposed by Chaves (2003) the crack is determined by solving a problem analogous to the heat conduction problem, established from local failure orientations, based on the stress state of the mechanical problem. To minimize the computational effort, in this paper a new strategy is proposed whereby the analysis for tracking the discontinuity path is restricted to the domain formed by some elements near the crack surface that develops along the loading process. The proposed methodology is validated by performing three-dimensional analyses of basic problems of experimental fractures and comparing their results with those reported in the literature.

Development of Convective Cell Identification and Tracking Algorithm using 3-Dimensional Radar Reflectivity Fields (3차원 레이더 반사도를 이용한 대류세포 판별과 추적 알고리즘의 개발)

  • Jung, Sung-Hwa;Lee, GyuWon;Kim, Hyung-Woo;Kuk, BongJae
    • Atmosphere
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    • v.21 no.3
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    • pp.243-256
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    • 2011
  • This paper presents the development of new algorithm for identifying and tracking the convective cells in three dimensional reflectivity fields in Cartesian coordinates. First, the radar volume data in spherical coordinate system has been converted into Cartesian coordinate system by the bilinear interpolation. The three-dimensional convective cell has then been identified as a group of spatially consecutive grid points using reflectivity and volume thresholds. The tracking algorithm utilizes a fuzzy logic with four membership functions and their weights. The four fuzzy parameters of speed, area change ratio, reflectivity change ratio, and axis transformation ratio have been newly defined. In order to make their membership functions, the normalized frequency distributions are calculated using the pairs of manually matched cells in the consecutive radar reflectivity fields. The algorithms have been verified for two convective events in summer season. Results show that the algorithms have properly identified storm cells and tracked the same cells successively. The developed algorithms may provide useful short-term forecasting or nowcasting capability of convective storm cells and provide the statistical characteristics of severe weather.

Three-dimensional Head Tracking Using Adaptive Local Binary Pattern in Depth Images

  • Kim, Joongrock;Yoon, Changyong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.16 no.2
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    • pp.131-139
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    • 2016
  • Recognition of human motions has become a main area of computer vision due to its potential human-computer interface (HCI) and surveillance. Among those existing recognition techniques for human motions, head detection and tracking is basis for all human motion recognitions. Various approaches have been tried to detect and trace the position of human head in two-dimensional (2D) images precisely. However, it is still a challenging problem because the human appearance is too changeable by pose, and images are affected by illumination change. To enhance the performance of head detection and tracking, the real-time three-dimensional (3D) data acquisition sensors such as time-of-flight and Kinect depth sensor are recently used. In this paper, we propose an effective feature extraction method, called adaptive local binary pattern (ALBP), for depth image based applications. Contrasting to well-known conventional local binary pattern (LBP), the proposed ALBP cannot only extract shape information without texture in depth images, but also is invariant distance change in range images. We apply the proposed ALBP for head detection and tracking in depth images to show its effectiveness and its usefulness.