To Örebro University

oru.seÖrebro University Publications
Change search
Refine search result
2345678 201 - 250 of 1393
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 201.
    Biro, Alexander
    Örebro University, School of Science and Technology.
    Combining adjustable autonomy and shared control as a new platform for controlling robotic systems with ROS on TurtleBot2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fully autonomous robotic systems can fulfill their functionality, without human interaction, but their efficiency is way lower, than a robotic system, which is teleoperated by a specialist. The teleoperation of robotic systems requires  continuously high attention from the operator, if this attention is taken away or reduced, the efficiency drops heavily. The combination of Adjustable Autonomy and Shared Control represent a promising approach, of how great efficiency could be maintained in a robotic system, with a minimum of human interaction.

     

    The goal of this project is the re-implementation of the utilitarian voting scheme for navigation for usage with modern robotic platforms, as proposed in the publication "Experiments in Adjustable Autonomy" by Jacob W. Crandall and Michael A. Goodrich. This voting scheme combines a proposed direction, which is given by a human operator, with environmental sensor data to determine the best direction for a robots next movement.

     

    The implemented prototype in this project was developed with ROS on TurtleBot and is processing the sensor data and calculating the best direction for the robot's movement in the same way, as the original prototype. Since the original setup consists of a Nomad SuperScout robot with sixteen sonar range finders, adjustments needed to be made, to run the same algorithm on a different setup. The  correct processing of the input data and estimation of the best direction was verified by pen and paper calculations. Finally, further ideas for improving the implemented prototype and usage in other scenarios were presented.

    Download full text (pdf)
    fulltext
  • 202.
    Biundo, Susanne
    et al.
    Universität Ulm, Ulm, Germany.
    Bidot, Julien
    Universität Ulm, Ulm, Germany.
    Schattenberg, Bernd
    Universität Ulm, Ulm, Germany.
    Planning in the real world2011In: Informatik-Spektrum, ISSN 0170-6012, E-ISSN 1432-122X, Vol. 34, no 5, p. 443-454Article in journal (Refereed)
    Abstract [en]

    In this article, we describe how real world planning problems can be solved by employing Artificial Intelligence planning techniques. We introduce the paradigm of hybrid planning, which is particularly suited for applications where plans are not intended to be automatically executed by systems, but are made for humans. Hybrid planning combines hierarchical planning – the stepwise refinement of complex tasks – with explicit reasoning about causal dependencies between actions, thereby reflecting exactly the kinds of reasoning humans perform when developing plans. We show how plans are generated and how failed plans are repaired in a way that guarantees stability. Our illustrating examples are taken from a domain model for disaster relief missions enforced upon extensive floods. Finally, we present a tool to support the challenging task of constructing planning domain models.

    The article ends with an overview of a wide varity of actual planning applications and outlines further such in the area of cognitive technical systems.

  • 203.
    Björnbom, Willie
    et al.
    Örebro University, School of Science and Technology.
    Eklöf, Alexander
    Örebro University, School of Science and Technology.
    VISUELL PRESENTATION AV VÄDERDATA OCH ELPRISERE TT ARBETE OM DATABASMODELLERING I MOLNET MED BUSINESS INTELLIGENCE2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In an environment where data flows everywhere and in all forms, it can be difficult to extract something valuable of it. Business Intelligence, also known as BI, is a technology used to transform information into a valuable resource for primarily companies with a lot of information. But what opportunities does BI offer? In this essay, we use standardized techniques, popular tools and cloud services to perform a pure BI project. We will generate a report in which we will analyze whether there is any correlation between electricity prices and different types of weather data. After the practical part of the work, we will use our experience of the cloud to dig deeper into how safe the cloud reallys is. We will compare the concerns that an ordinary user has to the cloud and compare with how the cloud service provider (CSP) Azure adapts to this.

    Download full text (pdf)
    fulltext
  • 204.
    Blanco, Jose Luis
    et al.
    University of Màlaga, Màlaga, Spain.
    Monroy, Javier G.
    University of Màlaga, Màlaga, Spain.
    Gonzalez-Jimenez, Javier
    University of Màlaga, Màlaga, Spain.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    A Kalman Filter Based Approach To Probabilistic Gas Distribution Mapping2013Conference paper (Refereed)
    Abstract [en]

    Building a model of gas concentrations has important indus-trial and environmental applications, and mobile robots ontheir own or in cooperation with stationary sensors play animportant role in this task. Since an exact analytical de-scription of turbulent flow remains an intractable problem,we propose an approximate approach which not only esti-mates the concentrations but also their variances for eachlocation. Our point of view is that of sequential Bayesianestimation given a lattice of 2D cells treated as hidden vari-ables. We first discuss how a simple Kalman filter pro-vides a solution to the estimation problem. To overcomethe quadratic computational complexity with the mappedarea exhibited by a straighforward application of Kalmanfiltering, we introduce a sparse implementation which runsin constant time. Experimental results for a real robot vali-date the proposed method.

    Download full text (pdf)
    fulltext
  • 205. Bloch, I.
    et al.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    On the representation of fuzzy spatial relations in robot maps2003In: Intelligent systems for information processing: from representation to applications / [ed] Bernadette Bouchon-Meunier, Laurent Foulloy, Ronald R. Yager, Amsterdam: Elsevier, 2003, p. 47-57Conference paper (Refereed)
    Abstract [en]

    Spatial directional relations, like "north of," play an important role in the modeling of the environment by an autonomous robot. We propose an approach to represent spatial relations grounded in fuzzy set theory and fuzzy mathematical morphology. We show how this approach can be applied to robot maps, and suggest that these relations can be used for self-localization and for reasoning about the environment. We illustrate our approach on real data collected by a mobile robot in an office environment

  • 206. Bloch, Isabelle
    et al.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Why robots should use fuzzy mathematical morphology2002Conference paper (Refereed)
    Abstract [en]

    Mobile robots must represent and reason about spatial knowledge acquired from sensor data which are inherently approximate and uncertain. While techniques based on fuzzy sets are increasingly used in this domain, the use of these techniques often rests on intuitive grounds. In this paper, we show that fuzzy mathematical morphology, a theory often used in image processing but mostly ignored in the robotic tradition, can provide a well grounded approach to the treatment of imprecise spatial knowledge in robotics

  • 207.
    Boldrin, Luca
    et al.
    University of Pauda.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    A modal logic for fusing partial belief of multiple reasoners1999In: Journal of logic and computation (Print), ISSN 0955-792X, E-ISSN 1465-363X, Vol. 9, no 1, p. 81-103Article in journal (Refereed)
    Abstract [en]

    We present PLn, a multi-agent epistemic logic in which each agent can perform uncertain (possibilistic) reasoning. The original feature of this logic is the presence of a distributed belief operator, with the purpose of merging the belief of different agents. Unlike the corresponding operator in the categorical (non-uncertain) case, our distributed belief operator accumulates support for the same fact coming from different agents. This means that opinions shared by different agents can be combined into a stronger distributed belief. This feature is useful in problems like pooling expert opinions and combining information from multiple unreliable sources. We provide a possible worlds semantics and an axiomatic calculus for our logic, and prove soundness, completeness and decidability results. We hint at some possible applications of PLn in the conclusions

  • 208.
    Bonaccorsi, Manuele
    et al.
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pontedera, Italy.
    Fiorini, L
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pontedera, Italy.
    Sathyakeerthy, Subhash
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Cavallo, Filippo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pontedera, Italy.
    Dario, Paolo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pontedera, Italy.
    Design of cloud robotic services for senior citizens to improve independent living in multiple environments2015In: Intelligenza Artificiale, ISSN 1724-8035, Vol. 9, no 1, p. 63-72Article in journal (Refereed)
    Abstract [en]

    The paper proposed a cloud robotic solution for the healthcare management of senior citizens, to demonstrate the opportunity to remotely provide continuous assistive robotic services to a number of seniors regardless to their position in the monitored environment. In particular, a medication reminding, a remote home monitoring and an user indoor localization service were outsourced in the cloud and provided to the robots, users and caregivers on request. The proposed system was composed of a number of robotic agents distributed over two smart environments: a flat at the Domocasa Lab (Peccioli, IT) and a condominium at the Angen site of the Orebro science park (Orebro, SE). The cloud acquired data from remote smart environments and enabled the local robots to provide advanced assistive services to a number of users. The proposed smart environments were able to collect raw data for the environmental monitoring and the localization of the users by means of wireless sensors, and provide such data to the cloud. On the cloud, specific algorithms improved the local robots, by providing event scheduling to accomplish assistive services and situation awareness on the users position and environments’ status. The indoor user localization service, was provided by means of commercial and ad-hoc sensors distributed over the environments and a sensor fusion algorithm on the cloud. The entire cloud solution was evaluated in terms of Quality of Service (QoS) to estimate the effectiveness of the architecture.

  • 209.
    Bonaccorsi, Manuele
    et al.
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Fiorini, Laura
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Cavallo, Filippo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Dario, Paolo
    The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy.
    A cloud robotics solution to improve social assistive robots for active and healthy aging2016In: International Journal of Social Robotics, ISSN 1875-4791, E-ISSN 1875-4805, Vol. 8, no 3, p. 393-408Article in journal (Refereed)
    Abstract [en]

    Technological innovation in robotics and ICT represents an effective solution to tackle the challenge of providing social sustainable care services for the ageing population. The recent introduction of cloud technologies is opening new opportunities for the provisioning of advanced robotic services based on the cooperation of a number of connected robots, smart environments and devices improved by the huge cloud computational and storage capability. In this context, this paper aims to investigate and assess the potentialities of a cloud robotic system for the provisioning of assistive services for the promotion of active and healthy ageing. The system comprised two different smart environments, located in Italy and Sweden, where a service robot is connected to a cloud platform for the provisioning of localization based services to the users. The cloud robotic services were tested in the two realistic environments to assess the general feasibility of the solution and demonstrate the ability to provide assistive location based services in a multiple environment framework. The results confirmed the validity of the solution but also suggested a deeper investigation on the dependability of the communication technologies adopted in such kind of systems.

  • 210.
    Bordignon, Mirko
    et al.
    Dept. of Information Engineering, University of Padova, Italy.
    Pagello, Enrico
    Dept. of Information Engineering, University of Padova, Italy.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    An inexpensive, off-the-shelf platform for networked embedded robotics2007In: Proceedings of the 1st international conference on Robot communication and coordination, RoboComm '07, Piscataway: IEEE press , 2007, p. Art no: 45-Conference paper (Refereed)
    Abstract [en]

    Recent years have witnessed the proliferation of a new class of devices, commonly referred to as Networked Embedded Devices. Their increasingly low cost and small size make them suited for large scale sensing applications. Likewise, they could be appealing as a means to embed intelligent actuation capabilities into the environment, turning simple artifacts into networked robotic appliances. The currently existing devices, however, are not suited for this development. In this paper, we present the PEIS-Mote: an open, general, small-size and inexpensive sensor-actuator node especially suited for networked robotics, and built from commonly available off-the-shelf components. This platform can run a popular operating system for sensor networks, TinyOS, which makes it interoperable with most commercially available sensor nodes.

  • 211.
    Borissov, Alexei
    et al.
    Örebro University, Örebro, Sweden.
    Janecek, Jakob
    Örebro University, Örebro, Sweden.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Towards a network robot system for object identification and localization in RoboCup@Home2008In: Proceedings of Workshop on Network Robot Systems at IROS'08, 2008Conference paper (Refereed)
    Abstract [en]

    This paper describes a realization of a network robot system for autonomous object localization and identification. Developing a ``Lost \& Found'' capability, the use of which can be envisaged in a wide range of applicative domains including domestic assistive scenarios, is a challenging task for current AI and robotic technology. Indeed, this task is currently one of the core challenges within the RoboCup@Home competition. A number of approaches for implementing a robust and general Lost \& Found functionality are feasible. In this paper we present a solution which integrates state-of-the-art intelligent software, robotic and sensory components in a distributed network of cooperating modules. This article describes the design and implementation of the system, provides a preliminary experimental evaluation and discusses the applicability of our approach to the RoboCup@Home challenge.

  • 212.
    Bothe, Hans-H.
    et al.
    Örebro University, Department of Technology.
    Persson, Martin
    Örebro University, Department of Technology.
    Biel, Lena
    Örebro University, Department of Technology.
    Rosenholm, Magnus
    Örebro University, Department of Technology.
    Multivariate sensor fusion by a neural network modelManuscript (preprint) (Other academic)
  • 213.
    Bouguerra, Abdel
    et al.
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    PC-SHOP: a probabilstic-conditional hierarchical task planner2005In: Intelligenza Artificiale, ISSN 1724-8035, Vol. 2, no 4, p. 44-50Article in journal (Refereed)
    Abstract [en]

    In this paper we report on the extension of the classical HTN planner SHOP to plan in partially observable domains with uncertainty. Our algorithm PC-SHOP uses belief states to handle situations involving incomplete and uncertain information about the state of the world. Sensing and acting are integrated in the primitive actions through the use of a stochastic model. PC-SHOP is showed to scale up well compared to some of the state-of-the-art planners. We outline the main characteristics of the algorithm, and present performance results on some problems found in the literature.

  • 214.
    Bouguerra, Abdelbaki
    Örebro University, Department of Technology.
    Robust execution of robot task-plans: a knowledge-based approach2008Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Autonomous mobile robots are being developed with the aim of accomplishing complex tasks in different environments, including human habitats as well as less friendly places, such as distant planets and underwater regions. A major challenge faced by such robots is to make sure that their actions are executed correctly and reliably, despite the dynamics and the uncertainty inherent in their working space. This thesis is concerned with the ability of a mobile robot to reliably monitor the execution of its plans and detect failures.

    Existing approaches for monitoring the execution of plans rely mainly on checking the explicit effects of plan actions, i.e., effects encoded in the action model. This supposedly means that the effects to monitor are directly observable, but that is not always the case in a real-world environment. In this thesis, we propose to use semantic domain-knowledge to derive and monitor implicit expectations about the effects of actions. For instance, a robot entering a room asserted to be an office should expect to see at least a desk, a chair, and possibly a PC. These expectations are derived from knowledge about the type of the room the robot is entering. If the robot enters a kitchen instead, then it should expect to see an oven, a sink, etc.

    The major contributions of this thesis are as follows.

    • We define the notion of Semantic Knowledge-based Execution Monitoring SKEMon, and we propose a general algorithm for it based on the use of description logics for representing knowledge.

    • We develop a probabilistic approach of semantic Knowledge-based execution monitoring to take into account uncertainty in both acting and sensing. Specifically, we allow for sensing to be unreliable and for action models to have more than one possible outcome. We also take into consideration uncertainty about the state of the world. This development is essential to the applicability of our technique, since uncertainty is a pervasive feature in robotics.

    • We present a general schema to deal with situations where perceptual information relevant to SKEMon is missing. The schema includes steps for modeling and generating a course of action to actively collect such information. We describe approaches based on planning and greedy action selection to generate the information-gathering solutions. The thesis also shows how such a schema can be applied to respond to failures occurring before or while an action is executed. The failures we address are ambiguous situations that arise when the robot attempts to anchor symbolic descriptions (relevant to a plan action) in perceptual information. The work reported in this thesis has been tested and verified using a mobile robot navigating in an indoor environment. In addition, simulation experiments were conducted to evaluate the performance of SKEMon using known metrics. The results show that using semantic knowledge can lead to high performance in monitoring the execution of robot plans.

    Download full text (pdf)
    FULLTEXT01
    Download (pdf)
    COVER01
    Download (pdf)
    ERRATA01
  • 215.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Åstrand, Björn
    Halmstad University, Halmstad, Sweden.
    Rögnvaldsson, Thorsteinn
    Halmstad University, Halmstad, Sweden.
    An autonomous robotic system for load transportation2009In: 2009 IEEE Conference on Emerging Technologies & Factory Automation (EFTA 2009), New York: IEEE conference proceedings, 2009, p. 1563-1566Conference paper (Refereed)
    Abstract [en]

    This paper presents an overview of an autonomous robotic material handling system. The goal of the system is to extend the functionalities of traditional AGVs to operate in highly dynamic environments. Traditionally, the reliable functioning of AGVs relies on the availability of adequate infrastructure to support navigation. In the target environments of our system, such infrastructure is difficult to setup in an efficient way. Additionally, the location of objects to handle are unknown, which requires that the system be able to detect and track object positions at runtime. Another requirement of the system is to be able to generate trajectories dynamically, which is uncommon in industrial AGV systems.

    Download full text (pdf)
    FULLTEXT01
  • 216.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Åstrand, Björn
    Halmstad University.
    Rögnvaldsson, Thorsteinn
    Halmstad University, Sweden.
    MALTA: a system of multiple autonomous trucks for load transportation2009In: Proceedings of the 4th European conference on mobile robots (ECMR) / [ed] Ivan Petrovic, Achim J. Lilienthal, 2009, p. 93-98Conference paper (Refereed)
    Abstract [en]

    This paper presents an overview of an autonomousrobotic material handling system. The goal of the system is toextend the functionalities of traditional AGVs to operate in highlydynamic environments. Traditionally, the reliable functioning ofAGVs relies on the availability of adequate infrastructure tosupport navigation. In the target environments of our system,such infrastructure is difficult to setup in an efficient way.Additionally, the location of objects to handle are unknown,which requires that the system be able to detect and track objectpositions at runtime. Another requirement of the system is to beable to generate trajectories dynamically, which is uncommon inindustrial AGV systems.

    Download full text (pdf)
    Fulltext
  • 217.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Hierarchical task planning under uncertainty2004Conference paper (Refereed)
    Abstract [en]

    In this paper we present an algorithm for planning in non-deterministic domains. Our algorithm C-SHOP extends the successful classical HTN planner SHOP, by introducing new mechanisms to handle situations where there is incomplete and uncertain information about the state of the environment. Being an HTN planner, C-SHOP supports coding domain-dependent knowledge in a powerful way that describes how to solve the planning problem.

    To handle uncertainty, belief states are used to represent incomplete information about the state of the world, and actions are allowed to have stochastic outcomes. This allows our algorithm to solve problems involving partial observability through feedback at execution time. We outline the main characteristics of the algorithm, and present performance results on some problems found in literature.

  • 218.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Symbolic probabilistic-conditional plans execution by a mobile robot2005Conference paper (Refereed)
    Abstract [en]

    In this paper we report on the integration of a high-level plan executor with a behavior-based architecture. The executor is designed to execute plans that solve problems in partially observable domains. We discuss the different modules of the overall architecture and how we made the different modules interact using a shared representation. We also give a detailed description of the hierarchical architecture of the executor and how execution-time failures are handled.

  • 219.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Synthesizing plans for multiple domains2005In: Abstraction, reformulation and approximation: Proceedings of the 6th international symposium, SARA 2005 / [ed] Jean-Daniel Zucker, Lorenza Saitta, Springer Berlin/Heidelberg, 2005, p. 30-43Conference paper (Refereed)
    Abstract [en]

    Intelligent agents acting in real world environments need to synthesize their course of action based on multiple sources of knowledge. They also need to generate plans that smoothly integrate actions from different domains. In this paper we present a generic approach to synthesize plans for solving planning problems involving multiple domains. The proposed approach performs search hierarchically by starting planning in one domain and considering subgoals related to the other domains as abstract tasks to be planned for later when their respective domains are considered. To plan in each domain, a domain-dependent planner can be used, making it possible to integrate different planners, possibly with different specializations. We outline the algorithm, and the assumptions underlying its functionality. We also demonstrate through a detailed example, how the proposed framework compares to planning in one global domain.

  • 220.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Handling uncertainty in semantic-knowledge based execution monitoring2007In: Intelligent Robots and Systems, 2007. IROS 2007. IEEE/RSJ International Conference on Oct. 29 2007-Nov. 2 2007, NEW YORK: IEEE , 2007, p. 443-449Chapter in book (Other academic)
    Abstract [en]

    Executing plans by mobile robots, in real world environments, faces the challenging issues of uncertainty and environment dynamics. Thus, execution monitoring is needed to verify that plan actions are executed as expected. Semantic domain-knowledge has lately been proposed as a source of information to derive and monitor implicit expectations of executing actions. For instance, when a robot moves into a room asserted to be an office, it would expect to see a desk and a chair. We propose to extend the semantic knowledge-based execution monitoring to take uncertainty in actions and sensing into account when verifying the expectations derived from semantic knowledge. We consider symbolic probabilistic action models, and show how semantic knowledge is used together with a probabilistic sensing model in the monitoring process of such actions. Our approach is illustrated by showing test scenarios ran in an indoor environment using a mobile robot

  • 221.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Handling uncertainty in semantic-knowledge based execution monitoring2007In: IEEE/RSJ international conference on intelligent robots and systems, IROS 2007 San Diego, CA, 2007, New York: IEEE , 2007, p. 437-443Conference paper (Refereed)
    Abstract [en]

    Executing plans by mobile robots, in real world environments, faces the challenging issues of uncertainty and environment dynamics. Thus, execution monitoring is needed to verify that plan actions are executed as expected. Semantic domain-knowledge has lately been proposed as a source of information to derive and monitor implicit expectations of executing actions. For instance, when a robot moves into a room asserted to be an office, it would expect to see a desk and a chair. We propose to extend the semantic knowledge-based execution monitoring to take uncertainty in actions and sensing into account when verifying the expectations derived from semantic knowledge. We consider symbolic probabilistic action models, and show how semantic knowledge is used together with a probabilistic sensing model in the monitoring process of such actions. Our approach is illustrated by showing test scenarios run in an indoor environment using a mobile robot.

  • 222.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Monitoring the execution of robot plans using semantic knowledge2008In: Robotics and Autonomous Systems, ISSN 0921-8890, E-ISSN 1872-793X, Vol. 56, no 11, p. 942-954Article in journal (Refereed)
    Abstract [en]

    Even the best laid plans can fail, and robot plans executed in real world domains tend to do so often. The ability of a robot to reliably monitor the execution of plans and detect failures is essential to its performance and its autonomy. In this paper, we propose a technique to increase the reliability of monitoring symbolic robot plans. We use semantic domain knowledge to derive implicit expectations of the execution of actions in the plan, and then match these expectations against observations. We present two realizations of this approach: a crisp one, which assumes deterministic actions and reliable sensing, and uses a standard knowledge representation system (LOOM); and a probabilistic one, which takes into account uncertainty in action effects, in sensing, and in world states. We perform an extensive validation of these realizations through experiments performed both in simulation and on real robots.

  • 223.
    Broxvall, Mathias
    et al.
    Örebro University, Department of Technology.
    Coradeschi, Silvia
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Have another look on failures and recovery planning in perceptual anchoring2004Conference paper (Refereed)
    Abstract [en]

    An important requirement for autonomous systems is the ability to detect and recover from exceptional situations such as failures in observations. In this paper we demonstrate how techniques for planning with sensing under uncertainty can play a major role in solving the problem of recovering from such situations. In this first step we concentrate on failures in perceptual anchoring, that is how to connect a symbol representing an object to the percepts of that object. We provide a classification of failures and present planning-based methods for recovering from them. We illustrate our approach by showing tests run on a mobile robot equipped with a color camera.

  • 224.
    Broxvall, Mathias
    et al.
    Örebro University, Department of Technology.
    Coradeschi, Silvia
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Recovery planning for ambiguous cases in perceptual anchoring2005In: Proceedings of the 20th national conference on Artificial intelligence, AAAI-05: volume 3, 2005, p. 1254-1260Conference paper (Refereed)
    Abstract [en]

    An autonomous robot using symbolic reasoning, sensing and acting in a real environment needs the ability to create and maintain the connection between symbols representing objects in the world and the corresponding perceptual representations given by its sensors. This connection has been named perceptual anchoring. In complex environments, anchoring is not always easy to establish: the situation may often be ambiguous as to which percept actually corresponds to a given symbol. In this paper, we extend perceptual anchoring to deal robustly with ambiguous situations by providing general methods for detecting them and recovering from them. We consider different kinds of ambiguous situations and present planning-based methods to recover from them. We illustrate our approach by showing experiments involving a mobile robot equipped with a color camera and an electronic nose.

  • 225.
    Broxvall, Mathias
    et al.
    Örebro University, School of Science and Technology.
    Daoutis, Marios
    Örebro University, School of Science and Technology.
    Developing Medical Image Processing Algorithms for GPU assisted parallel computation2013In: Computer Vision in Medical Imaging / [ed] C H Chen, World Scientific, 2013, p. 245-270Chapter in book (Refereed)
    Abstract [en]

    GPU’s have recently emerged as a significantly more powerful computing plat-form, capable of several orders of magnitude faster computations compared toCPU based approaches. However, they require significant changes in the algorithmic design compared to traditional programming paradigms. In this chapter we specifically introduce the reader to an overview of GPGPU development tools and the potential algorithmic pitfalls and bottlenecks when developing medical imaging algorithms for the GPU. We present a few general methodologies and building blocks for implementing fast image processing on GPUs. More specifically they include: methods for performing fast image convolutions and filtering;line detection, and bandwidth and memory considerations when processing volumetric datasets. Finally we conclude with a discourse on numerical precision as well as on mixing single floating-point versus double floating-point code.

  • 226.
    Broxvall, Mathias
    et al.
    Örebro University, School of Science and Technology. Centre of Biomedical Engineering Research (MTFC), Örebro University Hospital, Örebro, Sweden.
    Emilsson, Kent
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Clinical Physiology, Örebro University Hospital, Örebro, Sweden.
    Thunberg, Per
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Medical Physics and Centre of Biomedical Engineering Research (MTFC), Örebro University Hospital, Örebro, Sweden.
    Fast GPU based adaptive filtering of 4D echocardiography2012In: IEEE Transactions on Medical Imaging, ISSN 0278-0062, E-ISSN 1558-254X, Vol. 31, no 6, p. 1165-1172, article id 6099625Article in journal (Refereed)
    Abstract [en]

    Time resolved three-dimensional (3D) echocardiography generates four-dimensional (3D+time) data sets that bring new possibilities in clinical practice. Image quality of four-dimensional (4D) echocardiography is however regarded as poorer compared to conventional echocardiography where time-resolved 2D imaging is used. Advanced image processing filtering methods can be used to achieve image improvements but to the cost of heavy data processing. The recent development of graphics processing unit (GPUs) enables highly parallel general purpose computations, that considerably reduces the computational time of advanced image filtering methods. In this study multidimensional adaptive filtering of 4D echocardiography was performed using GPUs. Filtering was done using multiple kernels implemented in OpenCL (open computing language) working on multiple subsets of the data. Our results show a substantial speed increase of up to 74 times, resulting in a total filtering time less than 30 s on a common desktop. This implies that advanced adaptive image processing can be accomplished in conjunction with a clinical examination. Since the presented GPU processor method scales linearly with the number of processing elements, we expect it to continue scaling with the expected future increases in number of processing elements. This should be contrasted with the increases in data set sizes in the near future following the further improvements in ultrasound probes and measuring devices. It is concluded that GPUs facilitate the use of demanding adaptive image filtering techniques that in turn enhance 4D echocardiographic data sets. The presented general methodology of implementing parallelism using GPUs is also applicable for other medical modalities that generate multidimensional data.

  • 227.
    Broxvall, Mathias
    et al.
    Örebro University, Department of Technology.
    Karlsson, Lars
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Steps toward detecting and recovering from perceptual failures2004In: Proceedings of the 8th international conference on intelligent autonomous systems, 2004, p. 793-800Conference paper (Refereed)
    Abstract [en]

    An important requirement for autonomous systems is the ability to detect and recover from exceptional situations such as failures in observations. In this paper we investigate how traditional AI planning techniques can be used to reason about observations and to recover from these situations. In this first step we concentrate on failures in perceptual anchoring. We illustrate our approach by showing experiments run on a mobile robot equipped with a color camera.

  • 228.
    Broxvall, Mathias
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Interacting with a robot ecology using task templates2007In: 2007 RO-MAN: 16TH IEEE INTERNATIONAL SYMPOSIUM ON ROBOT AND HUMAN INTERACTIVE COMMUNICATION, VOLS 1-3, NEW YORK: IEEE , 2007, p. 486-491Chapter in book (Other academic)
    Abstract [en]

    Robot ecologies provide a new paradigm for assistive, service, industrial, and entertainment robotics which is quickly gaining popularity. These ecologies contain a large number of robotic components pervasively embedded in the environment and interacting with each other. Human users of such systems need to be able to interface with both the system as a whole and, if desired, which each individual component. The humans should be able to transmit, in a natural way, commands that range from basic ones, such as ''turn on the lights in the bedroom'', to abstract ones, such as ''bring me a cup of coffee''. Human users may also need to interact with task execution especially at decision points. In this paper, we introduce an approach to interface a human user to a specific type of robot ecology, called an ecology of Physically Embedded Intelligent Systems, or PEIS-Ecology. The ecology includes simple sensors and actuators and more complicated devices such as mobile robots. The proposed interface satisfies two requirements: 1) to easily and automatically generate component interfaces, and 2) to provide a simple mechanism by which to request and monitor the execution of tasks in the ecology.

  • 229.
    Bruno, Barbara
    et al.
    University of Genova, Genova, Italy.
    Chong, Nak Young
    Japan Advanced Institute of Science and Technology, Nomi [Ishikawa], Japan.
    Kamide, Hiroko
    Nagoya University, Nagoya, Japan.
    Kanoria, Sanjeev
    Advinia Health Care Limited LTD, London, UK.
    Lee, Jaeryoung
    Chubu University, Kasugai, Japan.
    Lim, Yuto
    Japan Advanced Institute of Science and Technology, Nomi [Ishikawa], Japan.
    Kumar Pandey, Amit
    SoftBank Robotics.
    Papadopoulos, Chris
    University of Bedfordshire, Luton, UK.
    Papadopoulos, Irena
    Middlesex University Higher Education Corporation, London, UK.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Sgorbissa, Antonio
    University of Genova, Genova, Italy.
    Paving the Way for Culturally Competent Robots: a Position Paper2017In: 2017 26th IEEE International Symposium on Robot and Human Interactive Communication (RO-MAN) / [ed] Howard, A; Suzuki, K; Zollo, L, New York: Institute of Electrical and Electronics Engineers (IEEE), 2017, p. 553-560Conference paper (Refereed)
    Abstract [en]

    Cultural competence is a well known requirementfor an effective healthcare, widely investigated in thenursing literature. We claim that personal assistive robotsshould likewise be culturally competent, aware of generalcultural characteristics and of the different forms they take indifferent individuals, and sensitive to cultural differences whileperceiving, reasoning, and acting. Drawing inspiration fromexisting guidelines for culturally competent healthcare and thestate-of-the-art in culturally competent robotics, we identifythe key robot capabilities which enable culturally competentbehaviours and discuss methodologies for their developmentand evaluation.

  • 230.
    Bruno, Barbara
    et al.
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Grosinger, Jasmin
    Örebro University, School of Science and Technology.
    Mastrogiovanni, Fulvio
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Sathyakeerthy, Subhash
    Örebro University, School of Science and Technology.
    Sgorbissa, Antonio
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Multi-modal sensing for human activity recognition2015In: Proceedings of the 24th IEEE International Symposium on Robot and Human Interactive Communication, Kobe, Japan, Aug 31 - Sept 4, 2015, New York: IEEE conference proceedings , 2015, p. 594-600Conference paper (Refereed)
    Abstract [en]

    Robots for the elderly are a particular category of home assistive robots, aiming at assisting the elderly inthe execution of daily life tasks to extend their independent life. To this aim, such robots should be able to determine the level of independence of the user and track its evolution over time, to adapt the assistance to the person capabilities and needs. Human Activity Recognition systems employ various sensing strategies, relying on environmental or wearable sensors,to recognize various daily life activities which provide insights on the health status of a person. The main contribution of the article is the design of an heterogeneous information management framework, allowing for the description of a wide variety of human activities in terms of multi-modal environmental and wearable sensing data and providing accurate knowledge about the user activity to any assistive robot.

  • 231.
    Bruno, Barbara
    et al.
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Mastrogiovanni, Fulvio
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Pecora, Federico
    Örebro University, School of Science and Technology.
    Sgorbissa, Antonio
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    A framework for Culture-aware Robots based on Fuzzy Logic2017In: 2017 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE), Institute of Electrical and Electronics Engineers (IEEE), 2017Conference paper (Refereed)
    Abstract [en]

    Cultural adaptation, i.e., the matching of a robot's behaviours to the cultural norms and preferences of its user, is a well known key requirement for the success of any assistive application. However, culture-dependent robot behaviours are often implicitly set by designers, thus not allowing for an easy and automatic adaptation to different cultures. This paper presents a method for the design of culture-aware robots, that can automatically adapt their behaviour to conform to a given culture. We propose a mapping from cultural factors to related parameters of robot behaviours which relies on linguistic variables to encode heterogeneous cultural factors in a uniform formalism, and on fuzzy rules to encode qualitative relations among multiple variables. We illustrate the approach in two practical case studies.

  • 232.
    Bruno, Barbara
    et al.
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Mastrogiovanni, Fulvio
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Sgorbissa, Antonio
    Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genova, Genova, Italy.
    Using fuzzy logic to enhance classification of human motion primitives2014In: Information processing and management of uncertainty in knowledge-based systems, PT II, Springer, 2014, p. 596-605Conference paper (Refereed)
    Abstract [en]

    The design of automated systems for the recognition of specific human activities is among the most promising research activities in Ambient Intelligence. The literature suggests the adoption of wearable devices, relying on acceleration information to model the activities of interest and distance metrics for the comparison of such models with the run-time data. Most current solutions do not explicitly model the uncertainty associated with the recognition, but rely on crisp thresholds and comparisons which introduce brittleness and inaccuracy in the system. We propose a framework for the recognition of simple activities in which recognition uncertainty is modelled using possibility distributions. We show that reasoning about this explicitly modelled uncertainty leads to a system with enhanced recognition accuracy and precision.

  • 233.
    Bucchiarone, Antonio
    et al.
    Fondazione Bruno Kessler, Trento, Italy.
    Dragoni, Nicola
    Örebro University, School of Science and Technology. DTU Compute, Distributed Syst & Secur, Technical University of Denmark, Lyngby, Denmark.
    Dustdar, Schahram
    TU Wien, Vienna, Austria.
    Larsen, Stephan T.
    Danske Bank, Copenhagen, Denmark.
    Mazzara, Manuel
    Innopolis University, Innopolis, Russia.
    From Monolithic to Microservices An Experience Report from the Banking Domain2018In: IEEE Software, ISSN 0740-7459, E-ISSN 1937-4194, Vol. 35, no 3, p. 50-55Article in journal (Refereed)
    Abstract [en]

    Microservices have seen their popularity blossoming with an explosion of concrete applications in real-life software. Several companies are currently involved in a major refactoring of their back-end systems in order to improve scalability. This article presents an experience report of a real-world case study, from the banking domain, in order to demonstrate how scalability is positively affected by reimplementing a monolithic architecture into microservices. The case study is based on the FX Core system for converting from one currency to another. FX Core is a mission-critical system of Danske Bank, the largest bank in Denmark and one of the leading financial institutions in Northern Europe.

  • 234.
    Bunz, Elsa
    et al.
    Örebro University, Örebro, Sweden.
    Chadalavada, Ravi Teja
    Örebro University, School of Science and Technology.
    Andreasson, Henrik
    Örebro University, School of Science and Technology.
    Krug, Robert
    Örebro University, School of Science and Technology.
    Schindler, Maike
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Spatial Augmented Reality and Eye Tracking for Evaluating Human Robot Interaction2016In: Proceedings of RO-MAN 2016 Workshop: Workshop on Communicating Intentions in Human-Robot Interaction, 2016Conference paper (Refereed)
    Abstract [en]

    Freely moving autonomous mobile robots may leadto anxiety when operating in workspaces shared with humans.Previous works have given evidence that communicating in-tentions using Spatial Augmented Reality (SAR) in the sharedworkspace will make humans more comfortable in the vicinity ofrobots. In this work, we conducted experiments with the robotprojecting various patterns in order to convey its movementintentions during encounters with humans. In these experiments,the trajectories of both humans and robot were recorded witha laser scanner. Human test subjects were also equipped withan eye tracker. We analyzed the eye gaze patterns and thelaser scan tracking data in order to understand how the robot’sintention communication affects the human movement behavior.Furthermore, we used retrospective recall interviews to aid inidentifying the reasons that lead to behavior changes.

    Download full text (pdf)
    fulltext
  • 235.
    Buschka, Pär
    Örebro University, Department of Technology.
    An investigation of hybrid maps for mobile robots2005Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Autonomous robots typically rely on internal representations of the environment, or maps, to plan and execute their tasks. Several types of maps have been proposed in the literature, and there is general consensus that different types have different advantages and limitations, and that each type is more suited to certain tasks and less to others. Because of these reasons, it is becoming common wisdom in the field of mobile robotics to use hybrid maps that integrate several representations, usually of different types. Hybrid maps provide scalability and multiple views, allowing for instance to combine robot-centered and human-centered representations. There is, however, little understanding of the general principles that can be used to combine different maps into a hybrid one, and to make it something more than the sum of its parts. There is no systematic analysis of the different ways in which different maps can be combined, and how they can be made to cooperate. This makes it difficult to evaluate and compare different systems, and precludes us from getting a clear understanding of how a hybrid map can be designed or improved.

    The investigation presented in this thesis aims to contribute to fill this foundational gap, and to get a clearer understanding of the nature of hybrid maps. To help in this investigation, we develop two tools: The first one is a conceptual tool, an analytical framework in which the main ingredients of a hybrid map are described; the second one is an empirical tool, a new hybrid map that allows us to experimentally verify our claims and hypotheses.

    While these tools are themselves important contributions of this thesis, our investigation has resulted in the following additional outcomes:

    • A set of concepts that allow us to better understand the structure and operation of hybrid maps, and that help us to design them, compare them, identify their problems, and possibly improve them;

    • The identification of the notion of synergy as the fundamental way in which component maps inside a hybrid map cooperate.

    To assess the significance of these outcomes, we make and validate the following claims:

    1. Our framework allows us to classify and describe existing maps in a uniform way. This claim is validated constructively by making a thorough classification of the hybrid maps reported in the literature.

    2. Our framework also allows us to enhance an existing hybrid map by identifying spots for improvement. This claim is verified experimentally by modifying an existing map and evaluating its performance against the original one.

    3. The notion of synergy plays an important role in hybrid maps. This claim is verified experimentally by testing the performance of a hybrid map with and without synergy.

    Download full text (pdf)
    FULLTEXT01
  • 236.
    Buschka, Pär
    et al.
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    A virtual sensor for room detection2002In: Proceedings of the IEEE/RSJ international conference on intelligent robots and systems: IROS - Lausanne, CH, 2002, 2002, p. 637-642Conference paper (Refereed)
    Abstract [en]

    Indoor environments typically consist of sets of connected room-like spaces. We present a local technique that uses range data to detect these spaces during navigation. Our technique includes two parts: segmentation, which isolates room-like spaces and detects when the robot has entered a new one; and feature extraction, which associates each space with a set of geometric features useful for navigation or recognition. Many such features can be considered: here we propose a new method to compute width and length of a rectangular room in a way which is largely invariant with respect to the configuration of the furniture. We report experimental results that show the performance of our technique, and hint at a possible use of this technique for coarse localization on a topological map

  • 237.
    Buschka, Pär
    et al.
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Room detection for topology-based map building2002In: Proceedings of the 2nd Swedish workshop on autonomous robots, 2002, p. 39-44Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Indoor environments typically consist of sets of connected room-like spaces. We present a local technique that uses range data to detect these spaces during navigation. This is done by a segmentation which isolates room-like spaces and detects when the robot has entered a new one. These spaces can be seen as nodes in a topological map and we show how to incrementally build such a map. We also report experimental results that show the performance of our technique

  • 238.
    Buschka, Pär
    et al.
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Some notes on the use of hybrid maps for mobile robots2004In: Proceedings of the 8th international conference on intelligent autonomous systems, 2004, p. 547-556Conference paper (Refereed)
    Abstract [en]

    Hybrid maps are quickly becoming popular in the field of mobile robotics. There is, however, little understanding of the general principles that can be used to combine different maps into a hybrid one, and to make these maps to cooperate. In this note, we propose a definition and a classification of hybrid maps, and discuss the synergies that can make a hybrid map something more than the sum of its parts. We illustrate these points with experimental results obtained on a metric-topological map.

  • 239.
    Buschka, Pär
    et al.
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Wasik, Zbigniew
    Örebro University, Department of Technology.
    Fuzzy landmark-based localization for a legged robot2000In: Proceedings, 2000 IEEE/RSJ International Conference on Intelligent Robots and Systems: IROS 2000 - Takamatsu, Japan, 2000, 2000, p. 1205-1210Conference paper (Refereed)
    Abstract [en]

    We describe a new technique for landmark-based self-localization which is suitable for robots with poor odometry. This technique uses fuzzy logic to account for errors and imprecision in visual recognition, and for extreme uncertainty in the estimate of the robot's motion. It only requires an approximate model of the sensor system and a qualitative estimate of the robot's displacement, and it has a moderate computational cost. We show examples of use of our technique on a Sony AIBO legged robot in the RoboCup domain.

  • 240.
    Bäck, Rasmus
    Örebro University, School of Science and Technology.
    Förstärkt verklighet på underjordiska gruvmaskiner2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Underground mining has for a long time been associated with an extremely dangerous professiondue to the nature of the work and the environment. Large efforts have been made to makemachines autonomous but there are situations and environments where manual operations areneeded. Teleoperation provides operators with the ability to supervise and operate the vehiclesin the mines from a remote location through visual and sensory feedback, immensely improvingtheir health and safety conditions. However, operators usually experience a decrease in vehicleto-environment awareness while operating remotely in opposition to operating on-board.Augmented reality has shown to be a great tool in many areas of application through its abilityto help users perform tasks through visualizing and displaying virtual information in real-time,in the real environment. This thesis was divided into two parts. The first part investigated themachine’s sensor capabilities to apply tracking technologies for augmented reality. As well asrelated studies on other implementations and systems that used and applied augmented reality.The second part investigated the Epiroc module’s hardware performance in regards to what anaugmented reality system requires, and evaluated the module’s processor performance througha system simulation test.In terms of applying augmented reality, the machine sensors provided the system with a greatplatform for a large range of applications and the ability to apply a variety of tracking technologiesto track the position and orientation of the operator’s view. The results from the investigationimplied that the Epiroc module lacks sufficient processing power to be able to provide the userwith a desired frame rate while applying augmented reality, without compromising other aspects.To overcome the module limitations, a proposal was made to implement a dedicated augmentedreality system that utilizes Epiroc’s network infrastructure.

    Download full text (pdf)
    fulltext
  • 241.
    Cajander, Åsa
    et al.
    Uppsala University, Uppsala, Sweden.
    Grünloh, Christiane
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Lind, Thomas
    Uppsala University, Uppsala, Sweden.
    Scandurra, Isabella
    Örebro University, Örebro University School of Business.
    Designing eHealth Services for Patients and Relatives: Critical Incidents and Lessons to Learn2016In: Proceedings of the NordiCHI '16: The 9th Nordic Conference on Human-Computer Interaction - game changing design, Association for Computing Machinery (ACM), 2016Conference paper (Refereed)
    Abstract [en]

    The number of eHealth services for patients and relatives is rapidly increasing as many countries are launching such services as a means to manage an ageing population, to increase efficiency in healthcare, and to empower patients. However, design and deployment of eHealth services for patients is challenging due to the complex setting and the multitude of affected stakeholders, which in turn make the task of eliciting and managing the needs and requirements equally challenging. Hence, this workshop(1) aims to make use of critical incident analysis as a method for collecting and jointly reflecting on practices, assumptions, and experiences in relation to the design, deployment, and use of eHealth services for patients and relatives. The goal of the workshop is to engage in joint reflection, and to find potential ways forward in relation to critical incidents as well as supporting the shaping and reshaping of eHealth design and development. This full day workshop invites researchers and practitioners to apply/provide their critical reflection in order to derive changed practices and theories about practice. We also especially invite the patients' perspective as this is crucial to achieve successful eHealth services. This workshop provides a venue for challenging the process of eHealth service design and development and is built around a concept of active participation, where the workshop participants will analyse and discuss the critical incidents together.

  • 242.
    Calatrava Nicolás, Francisco M.
    et al.
    Örebro University, School of Science and Technology.
    Martinez Mozos, Oscar
    Örebro University, School of Science and Technology.
    Light Residual Network for Human Activity Recognition using Wearable Sensor Data2023In: IEEE Sensors Letters, E-ISSN 2475-1472, Vol. 7, no 10, article id 7005304Article in journal (Refereed)
    Abstract [en]

    This letter addresses the problem of human activity recognition (HAR) of people wearing inertial sensors using data from the UCI-HAR dataset. We propose a light residual network, which obtains an F1-Score of 97.6% that outperforms previous works, while drastically reducing the number of parameters by a factor of 15, and thus the training complexity. In addition, we propose a new benchmark based on leave-one (person)-out cross-validation to standardize and unify future classifications on the same dataset, and to increase reliability and fairness in the comparisons.

  • 243.
    Can, Ozan Arkan
    et al.
    Koc University.
    Zuidberg Dos Martires, Pedro
    KU Leuven.
    Persson, Andreas
    Örebro University, School of Science and Technology.
    Gaal, Julian
    Osnabrück University.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    De Raedt, Luc
    KU Leuven.
    Yuret, Deniz
    Koc University.
    Saffiotti, Alessandro
    Örebro University, School of Science and Technology.
    Learning from Implicit Information in Natural Language Instructions for Robotic Manipulations2019In: Proceedings of the Combined Workshop on Spatial Language Understanding (SpLU) and Grounded Communication for Robotics (RoboNLP) / [ed] Archna Bhatia, Yonatan Bisk, Parisa Kordjamshidi, Jesse Thomason, Association for Computational Linguistics , 2019, p. 29-39, article id W19-1604Conference paper (Refereed)
    Abstract [en]

    Human-robot interaction often occurs in the form of instructions given from a human to a robot. For a robot to successfully follow instructions, a common representation of the world and objects in it should be shared between humans and the robot so that the instructions can be grounded. Achieving this representation can be done via learning, where both the world representation and the language grounding are learned simultaneously. However, in robotics this can be a difficult task due to the cost and scarcity of data. In this paper, we tackle the problem by separately learning the world representation of the robot and the language grounding. While this approach can address the challenges in getting sufficient data, it may give rise to inconsistencies between both learned components. Therefore, we further propose Bayesian learning to resolve such inconsistencies between the natural language grounding and a robot’s world representation by exploiting spatio-relational information that is implicitly present in instructions given by a human. Moreover, we demonstrate the feasibility of our approach on a scenario involving a robotic arm in the physical world.

  • 244.
    Canelhas, Daniel R.
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    From Feature Detection in Truncated Signed Distance Fields to Sparse Stable Scene Graphs2016In: IEEE Robotics and Automation Letters, ISSN 2377-3766, Vol. 1, no 2, p. 1148-1155Article in journal (Refereed)
    Abstract [en]

    With the increased availability of GPUs and multicore CPUs, volumetric map representations are an increasingly viable option for robotic applications. A particularly important representation is the truncated signed distance field (TSDF) that is at the core of recent advances in dense 3D mapping. However, there is relatively little literature exploring the characteristics of 3D feature detection in volumetric representations. In this paper we evaluate the performance of features extracted directly from a 3D TSDF representation. We compare the repeatability of Integral invariant features, specifically designed for volumetric images, to the 3D extensions of Harris and Shi & Tomasi corners. We also study the impact of different methods for obtaining gradients for their computation. We motivate our study with an example application for building sparse stable scene graphs, and present an efficient GPU-parallel algorithm to obtain the graphs, made possible by the combination of TSDF and 3D feature points. Our findings show that while the 3D extensions of 2D corner-detection perform as expected, integral invariants have shortcomings when applied to discrete TSDFs. We conclude with a discussion of the cause for these points of failure that sheds light on possible mitigation strategies.

    Download full text (pdf)
    fulltext
  • 245.
    Canelhas, Daniel R.
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Improved local shape feature stability through dense model tracking2013In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, 2013, p. 3203-3209Conference paper (Refereed)
    Abstract [en]

    In this work we propose a method to effectively remove noise from depth images obtained with a commodity structured light sensor. The proposed approach fuses data into a consistent frame of reference over time, thus utilizing prior depth measurements and viewpoint information in the noise removal process. The effectiveness of the approach is compared to two state of the art, single-frame denoising methods in the context of feature descriptor matching and keypoint detection stability. To make more general statements about the effect of noise removal in these applications, we extend a method for evaluating local image gradient feature descriptors to the domain of 3D shape descriptors. We perform a comparative study of three classes of such descriptors: Normal Aligned Radial Features, Fast Point Feature Histograms and Depth Kernel Descriptors; and evaluate their performance on a real-world industrial application data set. We demonstrate that noise removal enabled by the dense map representation results in major improvements in matching across all classes of descriptors as well as having a substantial positive impact on keypoint detection reliability

  • 246.
    Canelhas, Daniel R.
    et al.
    Örebro University, School of Science and Technology.
    Stoyanov, Todor
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    SDF tracker: a parallel algorithm for on-line pose estimation and scene reconstruction from depth images2013In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), IEEE, 2013, p. 3671-3676Conference paper (Refereed)
    Abstract [en]

    Ego-motion estimation and environment mapping are two recurring problems in the field of robotics. In this work we propose a simple on-line method for tracking the pose of a depth camera in six degrees of freedom and simultaneously maintaining an updated 3D map, represented as a truncated signed distance function. The distance function representation implicitly encodes surfaces in 3D-space and is used directly to define a cost function for accurate registration of new data. The proposed algorithm is highly parallel and achieves good accuracy compared to state of the art methods. It is suitable for reconstructing single household items, workspace environments and small rooms at near real-time rates, making it practical for use on modern CPU hardware

  • 247.
    Canelhas, Daniel Ricão
    Örebro University, School of Science and Technology.
    Truncated Signed Distance Fields Applied To Robotics2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis is concerned with topics related to dense mapping of large scale three-dimensional spaces. In particular, the motivating scenario of this work is one in which a mobile robot with limited computational resources explores an unknown environment using a depth-camera. To this end, low-level topics such as sensor noise, map representation, interpolation, bit-rates, compression are investigated, and their impacts on more complex tasks, such as feature detection and description, camera-tracking, and mapping are evaluated thoroughly. A central idea of this thesis is the use of truncated signed distance fields (TSDF) as a map representation and a comprehensive yet accessible treatise on this subject is the first major contribution of this dissertation. The TSDF is a voxel-based representation of 3D space that enables dense mapping with high surface quality and robustness to sensor noise, making it a good candidate for use in grasping, manipulation and collision avoidance scenarios.

    The second main contribution of this thesis deals with the way in which information can be efficiently encoded in TSDF maps. The redundant way in which voxels represent continuous surfaces and empty space is one of the main impediments to applying TSDF representations to large-scale mapping. This thesis proposes two algorithms for enabling large-scale 3D tracking and mapping: a fast on-the-fly compression method based on unsupervised learning, and a parallel algorithm for lifting a sparse scene-graph representation from the dense 3D map.

    The third major contribution of this work consists of thorough evaluations of the impacts of low-level choices on higher-level tasks. Examples of these are the relationships between gradient estimation methods and feature detector repeatability, voxel bit-rate, interpolation strategy and compression ratio on camera tracking performance. Each evaluation thus leads to a better understanding of the trade-offs involved, which translate to direct recommendations for future applications, depending on their particular resource constraints.

    Download full text (pdf)
    Truncated Signed Distance Fields Applied To Robotics
    Download (png)
    Bild
    Download (pdf)
    Spikblad
    Download (pdf)
    Cover
  • 248.
    Canovas, Juan-Pedro
    et al.
    University of Murcia, Spain.
    LeBlanc, Kevin
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Cooperative object localization using fuzzy logic2003In: Proceedings of the IEEE international conference on methods and models in automation and robotics: MMAR, 2003, p. 773-778Conference paper (Refereed)
    Abstract [en]

    Cooperative localization of objects is an important challenge in multi-robot systems. We propose a new approach to cooperative object localization by a group of communicating robots. In our approach we see each robot as an expert which provides unreliable information about the location of objects. The information provided by different robots is combined using fuzzy logic techniques, in order to reach agreement between the robots. This contrasts with current techniques, which average the information provided by different robots, and can incur well-known problems when information is unreliable. We have tested our technique on a team of Sony AIBO robots in the RoboCup domain. We present experimental results obtained by sharing information about the location of the ball

  • 249.
    Canovas, Juan-Pedro
    et al.
    University of Murcia, Spain.
    LeBlanc, Kevin
    Örebro University, Department of Technology.
    Saffiotti, Alessandro
    Örebro University, Department of Technology.
    Robust multi-robot object localization using fuzzy logic2005In: RoboCup 2004: robot soccer world cup VIII / [ed] Daniele Nardi, Martin Riedmiller, Claude Sammut, José Santos-Victor, Springer Berlin/Heidelberg, 2005, p. 247-261Conference paper (Refereed)
    Abstract [en]

    Cooperative localization of objects is an important challenge in multi-robot systems. We propose a new approach to this problem where we see each robot as an expert which shares unreliable information about object locations. The information provided by different robots is then combined using fuzzy logic techniques, in order to reach a consensus between the robots. This contrasts with most current probabilistic techniques, which average information from different robots in order to obtain a tradeoff, and can thus incur well-known problems when information is unreliable. In addition, our approach does not assume that the robots have accurate self-localization. Instead, uncertainty in the pose of the sensing robot is propagated to object position estimates. We present experimental results obtained on a team of Sony AIBO robots, where we share information about the location of the ball in the RoboCup domain

  • 250.
    Capuccini, Marco
    et al.
    Uppsala University, Uppsala, Sweden.
    Carlsson, Lars
    AstraZeneca R&D, Sweden.
    Norinder, Ulf
    Swedish Toxicology Sciences Research Center, Södertälje, Sweden.
    Spjuth, Ola
    Uppsala University, Uppsala, Sweden.
    Conformal prediction in Spark: Large-scale machine learning with confidence2015In: Proc. 2nd International Symposium on Big Data Computing / [ed] Raicu, I.; Rana, O.; Buyya, R., IEEE Computer Society , 2015, Vol. 1, p. 61-67Conference paper (Refereed)
2345678 201 - 250 of 1393
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf