19 research outputs found

    Intelligent vision-based navigation system for mobile robot: A technological review

    Get PDF
    Vision system is gradually becoming more important. As computing technology advances, it has been widely utilized in many industrial and service sectors. One of the critical applications for vision system is to navigate mobile robot safely. In order to do so, several technological elements are required. This article focuses on reviewing recent researches conducted on the intelligent vision-based navigation system for the mobile robot. These include the utilization of mobile robot in various sectors such as manufacturing, warehouse, agriculture, outdoor navigation and other service sectors. Multiple intelligent algorithms used in developing robot vision system were also reviewed

    Internationales Kolloquium über Anwendungen der Informatik und Mathematik in Architektur und Bauwesen : 20. bis 22.7. 2015, Bauhaus-Universität Weimar

    Get PDF
    The 20th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering will be held at the Bauhaus University Weimar from 20th till 22nd July 2015. Architects, computer scientists, mathematicians, and engineers from all over the world will meet in Weimar for an interdisciplinary exchange of experiences, to report on their results in research, development and practice and to discuss. The conference covers a broad range of research areas: numerical analysis, function theoretic methods, partial differential equations, continuum mechanics, engineering applications, coupled problems, computer sciences, and related topics. Several plenary lectures in aforementioned areas will take place during the conference. We invite architects, engineers, designers, computer scientists, mathematicians, planners, project managers, and software developers from business, science and research to participate in the conference

    Collaborative Perception From Data Association To Localization

    Get PDF
    During the last decade, visual sensors have become ubiquitous. One or more cameras can be found in devices ranging from smartphones to unmanned aerial vehicles and autonomous cars. During the same time, we have witnessed the emergence of large scale networks ranging from sensor networks to robotic swarms. Assume multiple visual sensors perceive the same scene from different viewpoints. In order to achieve consistent perception, the problem of correspondences between ob- served features must be first solved. Then, it is often necessary to perform distributed localization, i.e. to estimate the pose of each agent with respect to a global reference frame. Having everything set in the same coordinate system and everything having the same meaning for all agents, operation of the agents and interpretation of the jointly observed scene become possible. The questions we address in this thesis are the following: first, can a group of visual sensors agree on what they see, in a decentralized fashion? This is the problem of collaborative data association. Then, based on what they see, can the visual sensors agree on where they are, in a decentralized fashion as well? This is the problem of cooperative localization. The contributions of this work are five-fold. We are the first to address the problem of consistent multiway matching in a decentralized setting. Secondly, we propose an efficient decentralized dynamical systems approach for computing any number of smallest eigenvalues and the associated eigenvectors of a weighted graph with global convergence guarantees with direct applications in group synchronization problems, e.g. permutations or rotations synchronization. Thirdly, we propose a state-of-the art framework for decentralized collaborative localization for mobile agents under the presence of unknown cross-correlations by solving a minimax optimization prob- lem to account for the missing information. Fourthly, we are the first to present an approach to the 3-D rotation localization of a camera sensor network from relative bearing measurements. Lastly, we focus on the case of a group of three visual sensors. We propose a novel Riemannian geometric representation of the trifocal tensor which relates projections of points and lines in three overlapping views. The aforemen- tioned representation enables the use of the state-of-the-art optimization methods on Riemannian manifolds and the use of robust averaging techniques for estimating the trifocal tensor

    Visual Localization with Lines

    Get PDF
    Mobile robots must be able to derive their current location from sensor measurements in order to navigate fully autonomously. Positioning sensors like GPS output a global position but their precision is not sufficient for many applications; and indoors no GPS signal is received at all. Cameras provide information-rich data and are already used in many systems, e.g. for object detection and recognition. Therefore, this thesis investigates the possibility of additionally using cameras for localization. State-of-the-art methods are based on point observations but as man-made environments mostly consist of planar and linear structures which are perceived as lines, the focus in this thesis is on the use of image lines to derive the camera trajectory. To achieve this goal, multiple view geometry algorithms for line-based pose and structure estimation have to be developed. A prerequisite for these algorithms is that correspondences between line observations in multiple images which originate from the same spatial line are established. This thesis proposes a novel line matching algorithm for matching under small baseline motion which is designed with one-to-many matching in mind to tackle the issue of varying line segmentation. In contrast to other line matching solutions, the algorithm proposed leverages optical flow calculation and hence obviates the need for an expensive descriptor calculation. A two-view relative pose estimation algorithm is introduced which extracts the spatial line directions using parallel line clustering on the image lines in order to calculate the relative rotation. In lieu of the "Manhattan world" assumption, which is required by state-of-the-art methods, the approach proposed is less restrictive as it needs only lines of different directions; the angle between the directions is not relevant. In addition, the method proposed is in the order of one magnitude faster to compute. A novel line triangulation method is proposed to derive the scene structure from the images. The method is derived from the spatial transformation of Plücker lines and allows prior knowledge of the spatial line, like the precalculated directions from the parallel line clustering, to be integrated. The problem of degenerate configurations is analyzed, too, and a solution is developed which incorporates the optical flow vectors from the matching step as spatial points into the estimation. Lastly, all components are combined to a visual odometry pipeline for monocular cameras. The pipeline uses image-to-image motion estimation to calculate the camera trajectory. A scale adjustment based on the trifocal tensor is introduced which ensures the consistent scale of the trajectory. To increase the robustness, a sliding-window bundle adjustment is employed. All components and the visual odometry pipeline proposed are evaluated and compared to state-of-the-art methods on real world data of indoor and outdoor scenes. The evaluation shows that line-based visual localization is suitable to solve the localization task

    Internationales Kolloquium über Anwendungen der Informatik und Mathematik in Architektur und Bauwesen : 20. bis 22.7. 2015, Bauhaus-Universität Weimar

    Get PDF
    The 20th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering will be held at the Bauhaus University Weimar from 20th till 22nd July 2015. Architects, computer scientists, mathematicians, and engineers from all over the world will meet in Weimar for an interdisciplinary exchange of experiences, to report on their results in research, development and practice and to discuss. The conference covers a broad range of research areas: numerical analysis, function theoretic methods, partial differential equations, continuum mechanics, engineering applications, coupled problems, computer sciences, and related topics. Several plenary lectures in aforementioned areas will take place during the conference. We invite architects, engineers, designers, computer scientists, mathematicians, planners, project managers, and software developers from business, science and research to participate in the conference

    PID-based with Odometry for Trajectory Tracking Control on Four-wheel Omnidirectional Covid-19 Aromatherapy Robot

    Get PDF
    Inhalation therapy is one of the most popular treatments for many pulmonary conditions. The proposed Covid-19 aromatherapy robot is a type of Unmanned Ground Vehicle (UGV) mobile robot that delivers therapeutic vaporized essential oils or drugs needed to prevent or treat Covid-19 infections. It uses four omnidirectional wheels with a controlled speed to possibly move in all directions according to its trajectory. All motors for straight, left, or right directions need to be controlled, or the robot will be off-target. The paper presents omnidirectional four-wheeled robot trajectory tracking control based on PID and odometry. The odometry was used to obtain the robot's position and orientation, creating the global map. PID-based controls are used for three purposes: motor speed control, heading control, and position control. The omnidirectional robot had successfully controlled the movement of its four wheels at low speed on the trajectory tracking with a performance criterion value of 0.1 for the IAEH, 4.0 for MAEH, 0.01 for RMSEH, 0.00 for RMSEXY, and 0.06 for REBS. According to the experiment results, the robot's linear velocity error rate is 2%, with an average test value of 1.3 percent. The robot heading effective error value on all trajectories is 0.6%. The robot's direction can be monitored and be maintained at the planned trajectory. Doi: 10.28991/esj-2021-SPER-13 Full Text: PD

    Image Feature Information Extraction for Interest Point Detection: A Comprehensive Review

    Full text link
    Interest point detection is one of the most fundamental and critical problems in computer vision and image processing. In this paper, we carry out a comprehensive review on image feature information (IFI) extraction techniques for interest point detection. To systematically introduce how the existing interest point detection methods extract IFI from an input image, we propose a taxonomy of the IFI extraction techniques for interest point detection. According to this taxonomy, we discuss different types of IFI extraction techniques for interest point detection. Furthermore, we identify the main unresolved issues related to the existing IFI extraction techniques for interest point detection and any interest point detection methods that have not been discussed before. The existing popular datasets and evaluation standards are provided and the performances for eighteen state-of-the-art approaches are evaluated and discussed. Moreover, future research directions on IFI extraction techniques for interest point detection are elaborated

    Visuelle Detektion unabhängig bewegter Objekte durch einen bewegten monokularen Beobachter

    Get PDF
    The development of a driver assistant system supporting drivers in complex intersection situations would be a major achievement for traffic safety, since many traffic accidents happen in such situations. While this is a highly complex task, which is still not accomplished, this thesis focused on one important and obligatory aspect of such systems: The visual detection of independently moving objects. Information about moving objects can, for example, be used in an attention guidance system, which is a central component of any complete intersection assistant system. The decision to base such a system on visual input had two reasons: (i) Humans gather their information to a large extent visually and (ii) cameras are inexpensive and already widely used in luxury and professional vehicles for specific applications. Mimicking the articulated human head and eyes, agile camera systems are desirable. To avoid heavy and sensitive stereo rigs, a small and lightweight monocular camera system mounted on a pan-tilt unit has been chosen as input device. In this thesis information about moving objects has been used to develop a prototype of an attention guidance system. It is based on the analysis of sequences from a single freely moving camera and on measurements from inertial sensors rigidly coupled with the camera system.Die Entwicklung eines Fahrerassistenzsystems, welches den Fahrer in komplexen Kreuzungssituationen unterstützt, wäre ein wichtiger Beitrag zur Verkehrssicherheit, da sehr viele Unfälle in solchen Situationen passieren. Dies ist eine hochgradig komplexe Aufgabe und daher liegt der Fokus dieser Arbeit auf einen wichtigen und notwendigen Aspekt solcher Systeme: Die visuelle Detektion unabhängig bewegter Objekte. Informationen über bewegte Objekte können z.B. für ein System zur Aufmerksamkeitssteuerung verwendet werden. Solch ein System ist ein integraler Bestandteil eines jeden kompletten Kreuzungsassistenzssystems. Zwei Gründe haben zu der Entscheidung geführt, das System auf visuellen Daten zu stützen: (i) Der Mensch sammelt seine Informationen zum Großteil visuell und (ii) Kameras sind zum Einen günstig und zum Anderen bereits jetzt in vielen Fahrzeugen verfügbar. Agile Kamerasysteme sind nötig um den beweglichen menschlichen Kopf zu imitieren. Die Wahl einer kleinen und leichten monokularen Kamera, die auf einer Schwenk-Neige-Einheit montiert ist, vermeidet die Verwendung von schweren und empfindlichen Stereokamerasystemen. Mit den Informationen über bewegte Objekte ist in dieser Arbeit der Prototyp eines Fahrerassistenzsystems Aufmerksamkeitssteuerung entwickelt worden. Das System basiert auf der Analyse von Bildsequenzen einer frei bewegten Kamera und auf Messungen von der mit der Kamera starr gekoppelten Inertialsensorik

    Research on a modifeied RANSAC and its applications to ellipse detection from a static image and motion detection from active stereo video sequences

    Get PDF
    制度:新 ; 報告番号:甲3091号 ; 学位の種類:博士(国際情報通信学) ; 授与年月日:2010/2/24 ; 早大学位記番号:新535
    corecore