157 research outputs found

    Camera Marker Networks for Pose Estimation and Scene Understanding in Construction Automation and Robotics.

    Full text link
    The construction industry faces challenges that include high workplace injuries and fatalities, stagnant productivity, and skill shortage. Automation and Robotics in Construction (ARC) has been proposed in the literature as a potential solution that makes machinery easier to collaborate with, facilitates better decision-making, or enables autonomous behavior. However, there are two primary technical challenges in ARC: 1) unstructured and featureless environments; and 2) differences between the as-designed and the as-built. It is therefore impossible to directly replicate conventional automation methods adopted in industries such as manufacturing on construction sites. In particular, two fundamental problems, pose estimation and scene understanding, must be addressed to realize the full potential of ARC. This dissertation proposes a pose estimation and scene understanding framework that addresses the identified research gaps by exploiting cameras, markers, and planar structures to mitigate the identified technical challenges. A fast plane extraction algorithm is developed for efficient modeling and understanding of built environments. A marker registration algorithm is designed for robust, accurate, cost-efficient, and rapidly reconfigurable pose estimation in unstructured and featureless environments. Camera marker networks are then established for unified and systematic design, estimation, and uncertainty analysis in larger scale applications. The proposed algorithms' efficiency has been validated through comprehensive experiments. Specifically, the speed, accuracy and robustness of the fast plane extraction and the marker registration have been demonstrated to be superior to existing state-of-the-art algorithms. These algorithms have also been implemented in two groups of ARC applications to demonstrate the proposed framework's effectiveness, wherein the applications themselves have significant social and economic value. The first group is related to in-situ robotic machinery, including an autonomous manipulator for assembling digital architecture designs on construction sites to help improve productivity and quality; and an intelligent guidance and monitoring system for articulated machinery such as excavators to help improve safety. The second group emphasizes human-machine interaction to make ARC more effective, including a mobile Building Information Modeling and way-finding platform with discrete location recognition to increase indoor facility management efficiency; and a 3D scanning and modeling solution for rapid and cost-efficient dimension checking and concise as-built modeling.PHDCivil EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113481/1/cforrest_1.pd

    Design, Construction, Energy Modeling, and Navigation of a Six-Wheeled Differential Drive Robot to Deliver Medical Supplies inside Hospitals

    Get PDF
    Differential drive mobile robots have been the most ubiquitous kind of robots for the last few decades. As each of the wheels of a differential drive mobile robot can be controlled, it provides additional flexibility to the end-users in creating new applications. These applications include personal assistance, security, warehouse and distribution applications, ocean and space exploration, etc. In a clinic or hospital, the delivery of medicines and patients’ records are frequently needed activities. Medical personnel often find these activities repetitive and time-consuming. Our research was to design, construct, produce an energy model, and develop a navigation control method for a six-wheeled differential drive robot designed to deliver medical supplies inside the hospital. Such a robot is expected to lessen the workload of medical staff. Therefore, the design and implementation of a six-wheeled differential drive robot with a password-protected medicine carrier were presented. This password-protected medicine carrier ensures that only the authorized medical personnel can receive medical supplies. The low-cost robot base and the medicine carrier were built in real life. Besides the actual robot design and fabrication, a kinematic model for the robot was developed, and a navigation control algorithm to avoid obstacles was implemented using MATLAB/Simulink. The kinematic modeling is helpful for the robot to achieve better energy optimization. To develop the object avoidance algorithm, we investigated the use of the Robot Operating System (ROS) and the Simultaneous Localization and Mapping (SLAM) algorithm for the implementation of the mapping and navigation of a robotic platform named TurtleBot 2. Finally, using the Webot robot simulator, the navigation of the six-wheeled mobile robot was demonstrated in a hospital-like simulation environment

    Cooperative simultaneous localization and mapping framework

    Get PDF
    This research work is a contribution to develop a framework for cooperative simultaneous localization and mapping with multiple heterogeneous mobile robots. The presented research work contributes in two aspects of a team of heterogeneous mobile robots for cooperative map building. First it provides a mathematical framework for cooperative localization and geometric features based map building. Secondly it proposes a software framework for controlling, configuring and managing a team of heterogeneous mobile robots. Since mapping and pose estimation are very closely related to each other, therefore, two novel sensor data fusion techniques are also presented, furthermore, various state of the art localization and mapping techniques and mobile robot software frameworks are discussed for an overview of the current development in this research area. The mathematical cooperative SLAM formulation probabilistically solves the problem of estimating the robots state and the environment features using Kalman filter. The software framework is an effort toward the ongoing standardization process of the cooperative mobile robotics systems. To enhance the efficiency of a cooperative mobile robot system the proposed software framework addresses various issues such as different communication protocol structure for mobile robots, different sets of sensors for mobile robots, sensor data organization from different robots, monitoring and controlling robots from a single interface. The present work can be applied to number of applications in various domains where a priori map of the environment is not available and it is not possible to use global positioning devices to find the accurate position of the mobile robot. Therefore the mobile robot(s) has to rely on building the map of its environment and using the same map to find its position and orientation relative to the environment. The exemplary areas for applying the proposed SLAM technique are Indoor environments such as warehouse management, factory floors for parts assembly line, mapping abandoned tunnels, disaster struck environment which are missing maps, under see pipeline inspection, ocean surveying, military applications, planet exploration and many others. These applications are some of many and are only limited by the imagination.Diese Forschungsarbeit ist ein Beitrag zur Entwicklung eines Framework für kooperatives SLAM mit heterogenen, mobilen Robotern. Die präsentierte Forschungsarbeit trägt in zwei Aspekten in einem Team von heterogenen, mobilen Robotern bei. Erstens stellt es einen mathematischen Framework für kooperative Lokalisierung und geometrisch basierende Kartengenerierung bereit. Zweitens schlägt es einen Softwareframework zur Steuerung, Konfiguration und Management einer Gruppe von heterogenen mobilen Robotern vor. Da Kartenerstellung und Poseschätzung miteinander stark verbunden sind, werden zwei neuartige Techniken zur Sensordatenfusion präsentiert. Weiterhin werden zum Stand der Technik verschiedene Techniken zur Lokalisierung und Kartengenerierung sowie Softwareframeworks für die mobile Robotik diskutiert um einen Überblick über die aktuelle Entwicklung in diesem Forschungsbereich zu geben. Die mathematische Formulierung des SLAM Problems löst das Problem der Roboterzustandsschätzung und der Umgebungmerkmale durch Benutzung eines Kalman filters. Der Softwareframework ist ein Beitrag zum anhaltenden Standardisierungsprozess von kooperativen, mobilen Robotern. Um die Effektivität eines kooperativen mobilen Robotersystems zu verbessern enthält der vorgeschlagene Softwareframework die Möglichkeit die Kommunikationsprotokolle flexibel zu ändern, mit verschiedenen Sensoren zu arbeiten sowie die Möglichkeit die Sensordaten verschieden zu organisieren und verschiedene Roboter von einem Interface aus zu steuern. Die präsentierte Arbeit kann in einer Vielzahl von Applikationen in verschiedenen Domänen benutzt werden, wo eine Karte der Umgebung nicht vorhanden ist und es nicht möglich ist GPS Daten zur präzisen Lokalisierung eines mobilen Roboters zu nutzen. Daher müssen die mobilen Roboter sich auf die selbsterstellte Karte verlassen und die selbe Karte zur Bestimmung von Position und Orientierung relativ zur Umgebung verwenden. Die exemplarischen Anwendungen der vorgeschlagenen SLAM Technik sind Innenraumumgebungen wie Lagermanagement, Fabrikgebäude mit Produktionsstätten, verlassene Tunnel, Katastrophengebiete ohne aktuelle Karte, Inspektion von Unterseepipelines, Ozeanvermessung, Militäranwendungen, Planetenerforschung und viele andere. Diese Anwendungen sind einige von vielen und sind nur durch die Vorstellungskraft limitiert

    Development and evaluation of mixed reality-enhanced robotic systems for intuitive tele-manipulation and telemanufacturing tasks in hazardous conditions

    Get PDF
    In recent years, with the rapid development of space exploration, deep-sea discovery, nuclear rehabilitation and management, and robotic-assisted medical devices, there is an urgent need for humans to interactively control robotic systems to perform increasingly precise remote operations. The value of medical telerobotic applications during the recent coronavirus pandemic has also been demonstrated and will grow in the future. This thesis investigates novel approaches to the development and evaluation of a mixed reality-enhanced telerobotic platform for intuitive remote teleoperation applications in dangerous and difficult working conditions, such as contaminated sites and undersea or extreme welding scenarios. This research aims to remove human workers from the harmful working environments by equipping complex robotic systems with human intelligence and command/control via intuitive and natural human-robot- interaction, including the implementation of MR techniques to improve the user's situational awareness, depth perception, and spatial cognition, which are fundamental to effective and efficient teleoperation. The proposed robotic mobile manipulation platform consists of a UR5 industrial manipulator, 3D-printed parallel gripper, and customized mobile base, which is envisaged to be controlled by non-skilled operators who are physically separated from the robot working space through an MR-based vision/motion mapping approach. The platform development process involved CAD/CAE/CAM and rapid prototyping techniques, such as 3D printing and laser cutting. Robot Operating System (ROS) and Unity 3D are employed in the developing process to enable the embedded system to intuitively control the robotic system and ensure the implementation of immersive and natural human-robot interactive teleoperation. This research presents an integrated motion/vision retargeting scheme based on a mixed reality subspace approach for intuitive and immersive telemanipulation. An imitation-based velocity- centric motion mapping is implemented via the MR subspace to accurately track operator hand movements for robot motion control, and enables spatial velocity-based control of the robot tool center point (TCP). The proposed system allows precise manipulation of end-effector position and orientation to readily adjust the corresponding velocity of maneuvering. A mixed reality-based multi-view merging framework for immersive and intuitive telemanipulation of a complex mobile manipulator with integrated 3D/2D vision is presented. The proposed 3D immersive telerobotic schemes provide the users with depth perception through the merging of multiple 3D/2D views of the remote environment via MR subspace. The mobile manipulator platform can be effectively controlled by non-skilled operators who are physically separated from the robot working space through a velocity-based imitative motion mapping approach. Finally, this thesis presents an integrated mixed reality and haptic feedback scheme for intuitive and immersive teleoperation of robotic welding systems. By incorporating MR technology, the user is fully immersed in a virtual operating space augmented by real-time visual feedback from the robot working space. The proposed mixed reality virtual fixture integration approach implements hybrid haptic constraints to guide the operator’s hand movements following the conical guidance to effectively align the welding torch for welding and constrain the welding operation within a collision-free area. Overall, this thesis presents a complete tele-robotic application space technology using mixed reality and immersive elements to effectively translate the operator into the robot’s space in an intuitive and natural manner. The results are thus a step forward in cost-effective and computationally effective human-robot interaction research and technologies. The system presented is readily extensible to a range of potential applications beyond the robotic tele- welding and tele-manipulation tasks used to demonstrate, optimise, and prove the concepts

    Merging multi-modal information and cross-modal learning in artificial cognitive systems

    Get PDF
    Čezmodalno povezovanje je združevanje dveh ali več modalnih predstavitev lastnosti neke entitete v skupno predstavitev. Gre za eno temeljnih lastnosti spoznavnih sistemov, ki delujejo v kompleksnem okolju. Da bi se spoznavni sistemi uspešno prilagajali spremembam v dinamičnem okolju, je potrebno mehanizem čezmodalnega povezovanja nadgraditi s čezmodalnim učenjem. Morebiti še najtežja naloga pa je integracija obeh mehanizmov v spoznavni sistem. Njuna vloga v takem sistemu je dvojna: premoščanje semantičnih vrzeli med modalnostmi ter mediacija med nižjenivojskimi mehanizmi za obelavo senzorskih podatkov in višjenivojskimi spoznavnimi procesi, kot sta npr. motivacija in načrtovanje. V magistrski nalogi predstavljamo pristop k modeliranju verjetnostnega večmodalnega združevanja informacij v spoznavnih sistemih. S pomočjo mar-kov-skih logičnih omrežij formuliramo model čezmodalnega povezovanja in učenja ter opišemo načela njegovega vključevanja v spoznavne arhitekture. Prototip modela smo ovrednotili samostojno, z eksperimenti, ki simulirajo trimodalno spoznavno arhitekturo. Na podlagi našega pristopa oblikujemo, implementiramo in integriramo tudi podsistem prepričanj, ki premošča semantični prepad v prototipu spoznavnega sistema George. George je inteligenten robot, ki je sposoben zaznavanja in prepoznavanja predmetov iz okolice ter učenja njihovih lastnosti s pomočjo pogovora s človekom. Njegov poglavitni namen je preizkus različnih paradigem o interaktivnemu učenju konceptov. V ta namen smo izdelali in izvedli interaktivne eksperimente za vrednotenje Georgevih vedenjskih mehanizmov. S temi eksperimenti smo naš pristop k večmodalnemu združevanju informacij preizkusili in ovrednotili tudi kot del delujočega spoznavnega sistema.Cross-modal binding is the ability to merge two or more modal representations of the same entity into a single shared representation. This ability is one of the fundamental properties of any cognitive system operating in a complex environment. In order to adapt successfully to changes in a dynamic environment the binding mechanism has to be supplemented with cross-modal learning. But perhaps the most difficult task is the integration of both mechanisms into a cognitive system. Their role in such a system is two-fold: to bridge the semantic gap between modalities, and to mediate between the lower-level mechanisms for processing the sensory data, and the higher-level cognitive processes, such as motivation and planning. In this master thesis, we present an approach to probabilistic merging of multi-modal information in cognitive systems. By this approach, we formulate a model of binding and cross-modal learning in Markov logic networks, and describe the principles of its integration into a cognitive architecture. We implement a prototype of the model and evaluate it with off-line experiments that simulate a cognitive architecture with three modalities. Based on our approach, we design, implement and integrate the belief layer -- a subsystem that bridges the semantic gap in a prototype cognitive system named George. George is an intelligent robot that is able to detect and recognise objects in its surroundings, and learn about their properties in a situated dialogue with a human tutor. Its main purpose is to validate various paradigms of interactive learning. To this end, we have developed and performed on-line experiments that evaluate the mechanisms of robot\u27s behaviour. With these experiments, we were also able to test and evaluate our approach to merging multi-modal information as part of a functional cognitive system

    Laser-Based Detection and Tracking of Moving Obstacles to Improve Perception of Unmanned Ground Vehicles

    Get PDF
    El objetivo de esta tesis es desarrollar un sistema que mejore la etapa de percepción de vehículos terrestres no tripulados (UGVs) heterogéneos, consiguiendo con ello una navegación robusta en términos de seguridad y ahorro energético en diferentes entornos reales, tanto interiores como exteriores. La percepción debe tratar con obstáculos estáticos y dinámicos empleando sensores heterogéneos, tales como, odometría, sensor de distancia láser (LIDAR), unidad de medida inercial (IMU) y sistema de posicionamiento global (GPS), para obtener la información del entorno con la precisión más alta, permitiendo mejorar las etapas de planificación y evitación de obstáculos. Para conseguir este objetivo, se propone una etapa de mapeado de obstáculos dinámicos (DOMap) que contiene la información de los obstáculos estáticos y dinámicos. La propuesta se basa en una extensión del filtro de ocupación bayesiana (BOF) incluyendo velocidades no discretizadas. La detección de velocidades se obtiene con Flujo Óptico sobre una rejilla de medidas LIDAR discretizadas. Además, se gestionan las oclusiones entre obstáculos y se añade una etapa de seguimiento multi-hipótesis, mejorando la robustez de la propuesta (iDOMap). La propuesta ha sido probada en entornos simulados y reales con diferentes plataformas robóticas, incluyendo plataformas comerciales y la plataforma (PROPINA) desarrollada en esta tesis para mejorar la colaboración entre equipos de humanos y robots dentro del proyecto ABSYNTHE. Finalmente, se han propuesto métodos para calibrar la posición del LIDAR y mejorar la odometría con una IMU

    Development and testing of docking functions in industrial settings for an autonomous mobile robot based on ROS2

    Get PDF
    This dissertation is the result of a six-months internship at G.D S.p.A. for the preparation of the thesis project. The final goal is to develop algorithms on the ROS2 framework that could be used to control an Autonomous Mobile Robot during the operations of detection and approach of a docking station with high precision, needed to operate a recharge of the AMR itself or some operation on the host machines. The automation of these operations ensures a substantial increase in safety and productivity within a warehouse or host machine lines since it permits to the AMR to work without requiring an operator for longer time or even to substitute the operator itself. The presented method uses both lidars and an onboard camera. The trajectory from the starting position to the approximate area of the docking station is computed using data obtained from the three lidars around the AMR body. The final approach is implemented by detecting an ARUCO code positioned on the dock assembly through a camera. A sequence of intermediate positions is defined according to the pose estimations, and then reached with a mix of standard navigation and a proportional position control in the very last part of the movement trajectory. The precision of the docking position turned out to have less than one centimeter error around the desired target, the orientation error is a fraction of a degree. The docking times vary based on how far the AMR is from the docking station, but the last phase of the procedure is always completed in around seventeen seconds. The solution is implementable and will be evaluated on the real platform in the coming months

    Моделі, алгоритми та програмне забезпечення для планування шляху для навігації мобільних роботів з уникненням перешкод на основі дерева октантів

    Get PDF
    Об'єкт дослідження: процес оптимізації та покращення точності руху та уникнення перешкод для навігації мобільних роботів. Предмет дослідження: моделі та методи виявлення перешкод та навігації з метою уникнення виявлених перешкод. Мета магістерської роботи: підвищення ефективності системи розпізнавання перешкод мобільними роботами для навігації у середовищі, використовуючи датчики для забезпечення дороги без зіткнень з об’єктами, які не знаходяться на одному рівні з лазерами. Методи дослідження. Для вирішення поставлених задач використані методи: пошуку шляхів, порогового значення, обробки хмари точок, генерації дерева октантів. Наукова новизна полягає у тому, що удосконалено методи системи планування шляху для навігації мобільних роботів на основі дерева октантів для якісного та точного шляху від початкової точки до заданої у просторі

    Vega—A small, low cost, ground robot for nuclear decommissioning

    Get PDF
    From Wiley via Jisc Publications RouterHistory: received 2021-08-20, rev-recd 2021-11-03, accepted 2021-11-05, pub-electronic 2021-11-25Article version: VoRPublication status: PublishedFunder: Royal Academy of Engineering; Id: http://dx.doi.org/10.13039/501100000287Funder: Engineering and Physical Sciences Research Council; Id: http://dx.doi.org/10.13039/501100000266Abstract: This paper presents the Vega robot, which is a small, low cost, potentially disposable ground robot designed for nuclear decommissioning. Vega has been developed specifically to support characterization and inspection operations, such as 2D and 3D mapping, radiation scans and sample retrieval. The design and construction methodology that was followed to develop the robot is described and its capabilities detailed. Vega was designed to provide flexibility, both in software and hardware, is controlled via tele‐operation, although it can be extended to semi and full autonomy, and can be used in either tethered or untethered configurations. A version of the tethered robot was designed for extreme radiation tolerance, utilizing relay electronics and removing active electronic systems. Vega can be outfitted with a multitude of sensors and actuators, including gamma spectrometers, alpha/beta radiation sensors, LiDARs and robotic arms. To demonstrate its flexibility, a 5 degree‐of‐freedom manipulator has been successfully integrated onto Vega, facilitating deployments where handling is required. To assess the tolerance of Vega to the levels of ionizing radiation that may be found in decommissioning environments, its individual components were irradiated, allowing estimates to be made of the length of time Vega would be able to continue to operate in nuclear environments. Vega has been successfully deployed in an active environment at the Dounreay nuclear site in the UK, deployed in nonactive environments at the Atomic Weapons Establishment, and demonstrated to many other organizations in the UK nuclear industry including Sellafield Ltd, with the goal of moving to active deployments in the future
    corecore