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  • 151.
    Hernandez Bennetts, Victor
    et al.
    Örebro University, School of Science and Technology.
    Kamarudin, Kamarulzaman
    Center of Excellence for Advanced Sensor Technology, School of Mechatronics Engineering, Universiti Malaysia Perlis, Arau Perlis, Malaysia.
    Wiedemann, Thomas
    Institute of Communications and Navigation, German Aerospace Center, Oberpfaffenhofen, Germany.
    Kucner, Tomasz Piotr
    Örebro University, School of Science and Technology.
    Somisetty, Sai Lokesh
    Department of Mechatronics, Sastra University, Thanjavur, India.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Multi-Domain Airflow Modeling and Ventilation Characterization Using Mobile Robots, Stationary Sensors and Machine Learning2019In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, no 5, article id E1119Article in journal (Refereed)
    Abstract [en]

    Ventilation systems are critically important components of many public buildings and workspaces. Proper ventilation is often crucial for preventing accidents, such as explosions in mines and avoiding health issues, for example, through long-term exposure to harmful respirable matter. Validation and maintenance of ventilation systems is thus of key interest for plant operators and authorities. However, methods for ventilation characterization, which allow us to monitor whether the ventilation system in place works as desired, hardly exist. This article addresses the critical challenge of ventilation characterization-measuring and modelling air flow at micro-scales-that is, creating a high-resolution model of wind speed and direction from airflow measurements. Models of the near-surface micro-scale flow fields are not only useful for ventilation characterization, but they also provide critical information for planning energy-efficient paths for aerial robots and many applications in mobile robot olfaction. In this article we propose a heterogeneous measurement system composed of static, continuously sampling sensing nodes, complemented by localized measurements, collected during occasional sensing missions with a mobile robot. We introduce a novel, data-driven, multi-domain airflow modelling algorithm that estimates (1) fields of posterior distributions over wind direction and speed ("ventilation maps", spatial domain); (2) sets of ventilation calendars that capture the evolution of important airflow characteristics at measurement positions (temporal domain); and (3) a frequency domain analysis that can reveal periodic changes of airflow in the environment. The ventilation map and the ventilation calendars make use of an improved estimation pipeline that incorporates a wind sensor model and a transition model to better filter out sporadic, noisy airflow changes. These sudden changes may originate from turbulence or irregular activity in the surveyed environment and can, therefore, disturb modelling of the relevant airflow patterns. We tested the proposed multi-domain airflow modelling approach with simulated data and with experiments in a semi-controlled environment and present results that verify the accuracy of our approach and its sensitivity to different turbulence levels and other disturbances. Finally, we deployed the proposed system in two different real-world industrial environments (foundry halls) with different ventilation regimes for three weeks during full operation. Since airflow ground truth cannot be obtained, we present a qualitative discussion of the generated airflow models with plant operators, who concluded that the computed models accurately depicted the expected airflow patterns and are useful to understand how pollutants spread in the work environment. This analysis may then provide the basis for decisions about corrective actions to avoid long-term exposure of workers to harmful respirable matter.

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    Multi-Domain Airflow Modeling and Ventilation Characterization Using Mobile Robots, Stationary Sensors and Machine Learning
  • 152.
    Hernandez Bennetts, Victor
    et al.
    Örebro University, School of Science and Technology.
    Kucner, Tomasz Piotr
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany.
    Fan, Han
    Örebro University, School of Science and Technology.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Probabilistic Air Flow Modelling Using Turbulent and Laminar Characteristics for Ground and Aerial Robots2017In: IEEE Robotics and Automation Letters, ISSN 2377-3766, E-ISSN 1949-3045, Vol. 2, no 2, p. 1117-1123Article in journal (Refereed)
    Abstract [en]

    For mobile robots that operate in complex, uncontrolled environments, estimating air flow models can be of great importance. Aerial robots use air flow models to plan optimal navigation paths and to avoid turbulence-ridden areas. Search and rescue platforms use air flow models to infer the location of gas leaks. Environmental monitoring robots enrich pollution distribution maps by integrating the information conveyed by an air flow model. In this paper, we present an air flow modelling<?brk?> algorithm that uses wind data collected at a sparse number of locations to estimate joint probability distributions over wind speed and direction at given query locations. The algorithm uses a novel extrapolation approach that models the air flow as a linear combination of laminar and turbulent components. We evaluated the prediction capabilities of our algorithm with data collected with an aerial robot during several exploration runs. The results show that our algorithm has a high degree of stability with respect to parameter selection while outperforming conventional extrapolation approaches. In addition, we applied our proposed approach in an industrial application, where the characterization of a ventilation system is supported by a ground mobile robot. We compared multiple air flow maps recorded over several months by estimating stability maps using the Kullback&ndash;Leibler divergence between the distributions. The results show that, despite local differences, similar air flow patterns prevail over time. Moreover, we corroborated the validity of our results with knowledge from human experts.

  • 153.
    Hernandez Bennetts, Victor
    et al.
    Örebro University, School of Science and Technology.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Khaliq, Ali Abdul
    Örebro University, School of Science and Technology.
    Pomareda Sese, Victor
    Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.
    Trincavelli, Marco
    Örebro University, Örebro, Sweden..
    Gasbot: A Mobile Robotic Platform for Methane Leak Detection and Emission Monitoring2012In: Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Workshop on Robotics for Environmental Monitoring (WREM), Vilamoura, Portugal, October 7-12, 2012, 2012Conference paper (Refereed)
    Abstract [en]

    Due to its environmental, economical and safety implications, methane leak detection is a crucial task to address in the biogas production industry. In this paper, we introduce Gasbot, a robotic platform that aims to automatize methane emission monitoring in landfills and biogas production sites. The distinctive characteristic of the Gasbot platform is the use of a Tunable Laser Absorption Spectroscopy (TDLAS) sensor, along with a novel gas distribution algorithm to generate methane concentration maps of indoor and outdoor exploration areas. The Gasbot platform has been tested in two different scenarios: an underground corridor, where a pipeline leak was simulated and in a decommissioned landfill site, where an artificial methane emission source was introduced.

    Download full text (pdf)
    Gasbot: A mobile robotic platform for methane leak detection and emission monitoring
  • 154.
    Hoang, Dinh-Cuong
    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.
    Object-RPE: Dense 3D Reconstruction and Pose Estimation with Convolutional Neural Networks for Warehouse Robots2019In: 2019 European Conference on Mobile Robots, ECMR 2019: Proceedings, IEEE, 2019, article id 152970Conference paper (Refereed)
    Abstract [en]

    We present a system for accurate 3D instance-aware semantic reconstruction and 6D pose estimation, using an RGB-D camera. Our framework couples convolutional neural networks (CNNs) and a state-of-the-art dense Simultaneous Localisation and Mapping (SLAM) system, ElasticFusion, to achieve both high-quality semantic reconstruction as well as robust 6D pose estimation for relevant objects. The method presented in this paper extends a high-quality instance-aware semantic 3D Mapping system from previous work [1] by adding a 6D object pose estimator. While the main trend in CNN-based 6D pose estimation has been to infer object's position and orientation from single views of the scene, our approach explores performing pose estimation from multiple viewpoints, under the conjecture that combining multiple predictions can improve the robustness of an object detection system. The resulting system is capable of producing high-quality object-aware semantic reconstructions of room-sized environments, as well as accurately detecting objects and their 6D poses. The developed method has been verified through experimental validation on the YCB-Video dataset and a newly collected warehouse object dataset. Experimental results confirmed that the proposed system achieves improvements over state-of-the-art methods in terms of surface reconstruction and object pose prediction. Our code and video are available at https://sites.google.com/view/object-rpe.

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    Object-RPE: Dense 3D Reconstruction and Pose Estimation with Convolutional Neural Networks for Warehouse Robots
  • 155. Hristozov, Iasen
    et al.
    Iliev, Boyko
    Örebro University, Department of Technology.
    Eskiizmirliler, Selim
    A combined feature extraction method for an electronic nose2006In: Modern information processing: from theory to applications / [ed] Bernadette Bouchon-Meunier, Giulianella Coletti, Ronald Yager, Amsterdam: Elsevier, 2006, p. 453-466Chapter in book (Other academic)
  • 156.
    Hüllmann, Dino
    et al.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Kohlhoff, Harald
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Erdmann, Jessica
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Control of a spherical parallel manipulator with three degrees of freedom2018In: 35th Danubia-Adria Symposium on Advances in Experimental Mechanics: Extended abstracts / [ed] D. Ş. Pastramă, D. M. Constantinescu, Bukarest, Romania, 2018, p. 159-160Conference paper (Refereed)
    Abstract [en]

    In robotic applications, it is often necessary to orient a sensor quickly. Spherical parallel manipulators (SPM) are well suited for this purpose since they offer superior dynamics and structural stiffness as compared to serial manipulators. To control them, however, the kinematic equations have to be known. In this paper, a SPM with three degrees of freedom and the kinematic equations describing its mechanical properties are presented.

  • 157.
    Hüllmann, Dino
    et al.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Kohlhoff, Harald
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Erdmann, Jessica
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Current-independent torque control of permanent-magnet synchronous motors2017In: Materials Today: Proceedings, E-ISSN 2214-7853, Vol. 4, no 5, p. 5821-5826Article in journal (Refereed)
    Abstract [en]

    A current-independent torque equation for the permanent-magnet synchronous motor (PMSM) aiming at direct-drive servo applications is derived from a first principles model. Instead of measuring currents, all required control parameters are derived from optical incremental encoder measurements. The results are verified on a real system in test series showing the effect of static friction and proving the obtained torque model.

  • 158.
    Hüllmann, Dino
    et al.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Gas Dispersion Fluid Mechanics Simulation for Large Outdoor Environments2019In: 36th Danubia Adria Symposium on Advances in Experimental Mechanics: Extended Abstracts, Pilsen, Czech Republic: Danubia-Adria Symposium on Advances in Experimental Mechanics , 2019, p. 49-50Conference paper (Refereed)
    Abstract [en]

    The development of algorithms for mapping gas distributions and localising gas sources is a challenging task, because gas dispersion is a highly dynamic process and it is impossible to capture ground truth data. Fluid-mechanical simulations are a suitable way to support the development of these algorithms. Several tools for gas dispersion simulation have been developed, but they are not suitable for simulations of large outdoor environments. In this paper, we present a concept of how an existing simulator can be extended to handle both indoor and large outdoor scenarios.

  • 159.
    Hüllmann, Dino
    et al.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Monroy, Javier
    Machine Perception and Intelligent Robotics group (MAPIR), Universidad de Malaga, Spain.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    A Realistic Remote Gas Sensor Model for Three-Dimensional Olfaction Simulations2019In: ISOCS/IEEE International Symposium on Olfaction and Electronic Nose (ISOEN), IEEE, 2019, article id 8823330Conference paper (Refereed)
    Abstract [en]

    Remote gas sensors like those based on the Tunable Diode Laser Absorption Spectroscopy (TDLAS) enable mobile robots to scan huge areas for gas concentrations in reasonable time and are therefore well suited for tasks such as gas emission surveillance and environmental monitoring. A further advantage of remote sensors is that the gas distribution is not disturbed by the sensing platform itself if the measurements are carried out from a sufficient distance, which is particularly interesting when a rotary-wing platform is used. Since there is no possibility to obtain ground truth measurements of gas distributions, simulations are used to develop and evaluate suitable olfaction algorithms. For this purpose several models of in-situ gas sensors have been developed, but models of remote gas sensors are missing. In this paper we present two novel 3D ray-tracer-based TDLAS sensor models. While the first model simplifies the laser beam as a line, the second model takes the conical shape of the beam into account. Using a simulated gas plume, we compare the line model with the cone model in terms of accuracy and computational cost and show that the results generated by the cone model can differ significantly from those of the line model.

  • 160.
    Hüllmann, Dino
    et al.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Paul, Niels
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Kohlhoff, Harald
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Measuring rotor speed for wind vector estimation on multirotor aircraft2018In: Materials Today: Proceedings, E-ISSN 2214-7853, Vol. 5, no 13, p. 26703-26708Article in journal (Refereed)
    Abstract [en]

    For several applications involving multirotor aircraft, it is crucial to know both the direction and speed of the ambient wind. In this paper, an approach to wind vector estimation based on an equilibrium of the principal forces acting on the aircraft is shown. As the thrust force generated by the rotors depends on their rotational speed, a sensor to measure this quantity is required. Two concepts for such a sensor are presented: One is based on tapping the signal carrying the speed setpoint for the motor controllers, the other one uses phototransistors placed underneath the rotor blades. While some complications were encountered with the first approach, the second yields accurate measurement data. This is shown by an experiment comparing the proposed speed sensor to a commercial non-contact tachometer.

  • 161.
    Hüllmann, Dino
    et al.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Paul, Niels
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Neumann, Patrick P.
    Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany.
    Lilienthal, Achim
    Örebro University, School of Science and Technology.
    Motor Speed Transfer Function for Wind Vector Estimation on Multirotor Aircraft2017In: 34th Danubia-Adria Symposium on Advances in Experimental Mechanics: Book of proceedings / [ed] F. Cosmi, Trieste, Italy: EUT Edizioni Università di Trieste , 2017, p. 75-77Conference paper (Refereed)
    Abstract [en]

    A set of equations is derived to estimate the 3D wind vector with a multirotor aircraft using the aircraft itself as a flying anemometer. Since the thrust component is required to compute the wind vector, the PWM signal controlling the motors of the aircraft is measured and a transfer function describing the relation between the PWM signal and the rotational speed of the motors is derived.

  • 162.
    Iliev, Boyko
    Örebro University, Department of Technology.
    Minimum-time sliding mode control of robot manipulators2002Licentiate thesis, monograph (Other academic)
  • 163.
    Iliev, Boyko
    Örebro University, Department of Technology.
    Minimum-time sliding mode control of robot manipulators2004Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Robot manipulators have a complex and highly nonlinear dynamics, accompanied with a high degree of uncertainty. These properties make them difficult for time-optimal control. The theory of sliding mode control can provide methods, able to cope with the uncertainty and nonlinearity in the system. However, besides the chattering problem it does not provide

    time-optimal behavior. The optimal control theory provides the appropriate design methodology for minimum-time control, but the designed system lacks robustness. In this thesis we combine these two approaches to obtain new control techniques, which have the robust properties of the sliding mode control and a performance, close to the time-optimal control. Two methods for minimum-time sliding mode control based on the concept of maximum slope sliding line are developed with a theoretical proof of their properties.

    In the time-optimal sliding mode control we prove that the time-optimal switching line of a simple linear system (double integrator) can be used as a sliding surface for a complex second order nonlinear system (robot manipulator) if the control gain is sufficiently high. Optimal

    performance is achieved by scaling the surface in such way that the maximum control action is efficiently used.

    The fuzzy minimum-time sliding mode control is developed employing a Takagi-Sugeno

    fuzzy model for the sliding surface. We demonstrate that designs, based on a single sliding line tend to be conservative, due to the nonlinearities in the robot's dynamics. The Takagi-Sugeno model represents the maximum slope sliding lines for different values of the joint angles taking into account the variation in the gravity and inertia terms. This gives a convenient way to provide adaptation and incorporate additional knowledge in the controller design.

    Design procedures for all the methods are developed and evaluated in simulation and in experiments with real robot manipulators.

  • 164.
    Iliev, Boyko
    et al.
    Örebro University, Department of Technology.
    Kalaykov, Ivan
    Örebro University, Department of Technology.
    Minimum-time sliding mode control for second-order systems2004In: Proceedings of the 2004 American control conference, 2004: vol 1, 2004, p. 626-631Conference paper (Refereed)
    Abstract [en]

    Our approach for near time-optimal control is based on Takagi-Sugeno fuzzy model of the maximum slope SMC sliding surface as an adaptive technique for tuning the current slope of the sliding surface to the maximum feasible slope depending on the current state of system. The stability conditions of this method are proved and respective measures about the feasible maximum slope are presented. Experimental results demonstrate the system behaviour.

  • 165.
    Iliev, Boyko
    et al.
    Örebro University, Department of Technology.
    Lindquist, Malin
    Örebro University, Department of Technology.
    Robertsson, Linn
    Örebro University, Department of Technology.
    Wide, Peter
    Örebro University, Department of Technology.
    A fuzzy technique for food- and water quality assessment with an electronic tongue2006In: Fuzzy sets and systems (Print), ISSN 0165-0114, E-ISSN 1872-6801, Vol. 157, no 9, p. 1155-1168Article in journal (Refereed)
    Abstract [en]

    The problem of food- and water quality assessment is important for many practical applications, such as food industry and environmental monitoring. In this article we present a method for fast online quality assessment based on electronic tongue measurements. The idea is implemented in two steps. First we apply a fuzzy clustering technique to obtain prototypes corresponding to good and bad quality from a set of training data. During the second, online step we evaluate the membership of the current measurement to each cluster and make a decision about its quality. The result is presented to the user in a simple and understandable way, similar to the concept of traffic light signals. Namely, good quality is indicated with by a green light, bad quality with a red one, and a yellow light is a warning signal. The approach is demonstrated in two case studies: quality assessment of drinking water and baby food.

  • 166.
    Ishida, Hiroshi
    et al.
    Tokyo University of Agriculture and Technology, Tokyo, Japan.
    Lilienthal, Achim J.
    Örebro University, School of Science and Technology.
    Matsukura, Haruka
    Tokyo University of Agriculture and Technology, Tokyo, Japan.
    Hernandez Bennetts, Victor
    Örebro University, School of Science and Technology.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Using Chemical Sensors as 'Noses' for Mobile Robots2016In: Essentials of Machine Olfaction and Taste / [ed] Takamichi Nakamoto, Singapore: John Wiley & Sons, 2016, p. 219-246Chapter in book (Refereed)
    Abstract [en]

    Gas sensors detect the presence of gaseous chemical compounds in air. They are often used in the form of gas alarms for detecting dangerous or hazardous gases. However, a limited number of stationary gas alarms may not be always sufficient to cover a large industrial facility. Human workers having a portable gas detector in their hand needs to be sent to thoroughly check gas leaks in the areas not covered by stationary gas alarms. However, making repetitive measurements with a gas detector at a number of different locations is laborious. Moreover, the places where the gas concentration level needs to be checked are often potentially dangerous for human workers. If a portable gas detector is mounted on a mobile robot, the task of patrolling in an industrial facility for checking a gas leak can be automated. Robots are good at doing repetitive tasks, and can be sent into harsh environments.

  • 167.
    Jadidi, Maani Ghaffari
    et al.
    Fac Engn & IT, Univ Technol Sydney, Sydney NSW, Australia.
    Miro, Jaime Valls
    Fac Engn & IT, Univ Technol Sydney, Sydney NSW, Australia.
    Valencia, Rafael
    Örebro University, School of Science and Technology.
    Andrade-Cetto, Juan
    Inst Robot & Informat Ind, Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de Catalunya (UPC), Barcelona, Spain.
    Exploration on Continuous Gaussian Process Frontier Maps2014In: 2014 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), IEEE conference proceedings, 2014, p. 6077-6082Conference paper (Refereed)
    Abstract [en]

    An information-driven autonomous robotic exploration method on a continuous representation of unknown environments is proposed in this paper. The approach conveniently handles sparse sensor measurements to build a continuous model of the environment that exploits structural dependencies without the need to resort to a fixed resolution grid map. A gradient field of occupancy probability distribution is regressed from sensor data as a Gaussian process providing frontier boundaries for further exploration. The resulting continuous global frontier surface completely describes unexplored regions and, inherently, provides an automatic stop criterion for a desired sensitivity. The performance of the proposed approach is evaluated through simulation results in the well-known Freiburg and Cave maps.

  • 168.
    Jafari, Raheleh
    et al.
    Centre for Artificial Intelligence Research (CAIR), University of Agder, Grimstad, Norway.
    Razvarz, Sina
    Departamento de Control Automático, CINVESTAV-IPN (National Polytechnic Institute), Mexico City, Mexico.
    Gegov, Alexander
    School of Computing, University of Portsmouth, Portsmouth, UK.
    Paul, Satyam
    Örebro University, School of Science and Technology. School of Engineering and Sciences, Tecnológico de Monterrey, Monterrey, Mexico.
    Fuzzy Modeling for Uncertain Nonlinear Systems Using Fuzzy Equations and Z-Numbers2019In: Advances in Intelligent Systems and Computing / [ed] Lotfi, Ahmad; Bouchachia, Hamid; Gegov, Alexander; Langensiepen, Caroline; McGinnity, Martin, Springer, 2019, Vol. 840, p. 96-107Conference paper (Refereed)
    Abstract [en]

    In this paper, the uncertainty property is represented by Z-number as the coefficients and variables of the fuzzy equation. This modification for the fuzzy equation is suitable for nonlinear system modeling with uncertain parameters. Here, we use fuzzy equations as the models for the uncertain nonlinear systems. The modeling of the uncertain nonlinear systems is to find the coefficients of the fuzzy equation. However, it is very difficult to obtain Z-number coefficients of the fuzzy equations.

    Taking into consideration the modeling case at par with uncertain nonlinear systems, the implementation of neural network technique is contributed in the complex way of dealing the appropriate coefficients of the fuzzy equations. We use the neural network method to approximate Z-number coefficients of the fuzzy equations.

  • 169.
    Jafari, Raheleh
    et al.
    Agder University College, Grimstad, Norway.
    Razvarz, Sina
    National Polytechnic Institute, Mexico City, Mexico.
    Gegov, Alexander
    University of Portsmouth, Portsmouth, UK.
    Paul, Satyam
    National Polytechnic Institute, Mexico City, Mexico.
    Modeling and Control of Uncertain Nonlinear Systems2018Conference paper (Refereed)
    Abstract [en]

    A survey of the methodologies associated with the modeling and control of uncertain nonlinear systems has been given due importance in this paper. The basic criteria that highlights the work is relied on the various patterns of techniques incorporated for the solutions of fuzzy equations that corresponds to fuzzy controllability subject. The solutions which are generated by these equations are considered to be the controllers. Currently, numerical techniques have come out as superior techniques in order to solve these types of problems. The implementation of neural networks technique is contributed in the complex way of dealing the appropriate coefficients and solutions of the fuzzy systems.

  • 170.
    Johansson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    de Vin, Leo J.
    Centre for Intelligent Automation, University of Skövde, Sweden.
    A low cost video see-through head mounted display for increased situation awareness in an augmented environmentManuscript (preprint) (Other academic)
    Abstract [en]

    A head mounted display is developed for use in an augmented reality immersive simulator for virtual training. The simulator requires a video see-through parallax-free display to accurately mix the real and virtual worlds. High field of view is also required to allow use of peripheral vision in order to create a higher sense of awareness for the user. Due to high cost associated with commercial off-the-shelf display systems, a custom solution is designed and developed by combining hardware and software. It’s shown that it’s possible to build a low cost display system that provides the necessary attributes and acceptable compromises for the current type of application.

  • 171.
    Johansson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    de Vin, Leo J.
    Centre for Intelligent Automation, University of Skövde, Sweden.
    An augmented virtuality simulator with an intuitive interface: concept, design and implementationManuscript (preprint) (Other academic)
    Abstract [en]

    This paper describes the design and implementation of a simulator in which users can move untethered in a mixed reality where the boundary between real and virtual objects is minimal. A wide field of view, inexpensive, custom-built video see-through head-mounted display is used in combination with wireless image transfers, natural position displacement and software chroma keying. The result is a simulator that facilitates a high grade of presence with a user interface that allows a high degree of mobility.

  • 172.
    Johansson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    de Vin, Leo J.
    Centre for Intelligent Automation, University of Skövde, Sweden.
    Design and development of an augmented environment with high user mobility for training purposes2008In: Proceedings of the 11th Mechatronics Forum Biennial International Conference: 23 – 25 June2008, Universith of Limerick, Ireland / [ed] Toal D., Limerick: University of Limerick , 2008Conference paper (Other academic)
    Abstract [en]

    The paper describes the design and development of a novel cost effective simulator for training of situation awareness, strategy and co-operation. By mixing real and virtual realities in combination with wireless and body-mounted hardware, the result is an augmented environment that allows for high physical mobility against a relatively low cost.

  • 173.
    Johansson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    de Vin, Leo J.
    University of Skövde.
    Design and evaluation of an omnidirectional active floor for synthetic environmentsManuscript (preprint) (Other academic)
    Abstract [en]

    In the case of an application with a freely moving user it could be feasible that a simulator that facilitates real running, walking, and crawling can achieve a higher feeling of presence and situation awareness, and therefore potential training effect, compared to a simulator without such facilities. Omnidirectional walking is a research topic that has yielded a number of diverse solutions, but most are still within their prototype stages. Solutions can be expensive, mechanically complicated and in some cases unpractical. The complexity of existing solutions stems in the fact that they are two dimensional, given the normal two dimensional translation of human walking. If instead the problem is viewed upon from an angle of effect, another alternative is available. A two dimensional floor has the purpose to constantly allow translation in any direction, while it also transports the user towards its central region. This is to always have a marginal in all directions for changes in user translation direction or velocity. The effect of this is that a floor could be constructed to always facilitate transportation of the user towards its center, regardless of where on the floor’s surface the user is situated. This paper describes the design and evaluation of a powered omnidirectional floor that reduces the complexity of omnidirectional walking from two dimensions to one dimension. The floor is utilized to create a synthetic environment for training.

  • 174.
    Johansson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    de Vin, Leo J.
    Centre for Intelligent Automation University of Skövde, Skövde, Sweden.
    Omnidirectional robotic telepresence through augmented virtuality for increased situation awareness in hazardous environments2009In: Proceedings 2009 IEEE International Conference on  Systems, Man and Cybernetics, IEEE conference proceedings, 2009, p. 6-11Conference paper (Other academic)
    Abstract [en]

    This paper proposes a novel low-cost robotic telepresence approach to situation awareness, initially aimed for hazardous environments. The robot supports omnidirectional movement, wide field of vision, haptic feedback and binaural sound. It is controlled through an augmented virtuality environment with an intuitive position displacement scheme that supports physical mobility. The operator thereby can conduct work away from danger whilst retaining situation awareness of the real environment.

  • 175.
    Johansson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    de Vin, Leo J.
    University of Skövde.
    Towards convergence in a virtual environment: omnidirectional movement, physical feedback, social interaction and visionManuscript (preprint) (Other academic)
    Abstract [en]

    Movement, physical feedback, social interaction and vision are important factors for humans in the real world, and therefore also in a virtual world whose aim is to mimic the real world. The effect of a virtual environment application could increase through the use of a human-computer interface that can match natural human capability in such areas, and several novel components are presented herein. Here, movement and feedback is gained through an omnidirectional walking surface that enables untethered movement throughout a virtual world without imposing physical restrictions. Although several different approaches exist to the mechanical problem of two-dimensional translation, an alternative top-down approach can reduce complexity to one-dimensional space. Furthermore, interchange of subtle body language can be vital and achieved with a system that supports high fidelity in virtual texture representation of users, which can be more powerful in some cases than virtual geometry. Also, a new approach is taken to the design of a head mounted display with minimal weight through optics in the form of soft contact lenses, mounted directly on the eyes.

  • 176.
    Junges, Robert
    et al.
    Örebro University, School of Science and Technology.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Behavior modeling from learning agents: sensitivity to objective function details2012In: Proceedings of the 11th International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2012): volume 3 / [ed] Conitzer,Winikoff, Padgham, and van der Hoek, Richland SC: The International Foundation for Autonomous Agents and Multiagent Systems (IFAAMAS), 2012, p. 1335-1336Conference paper (Refereed)
    Abstract [en]

    The process of finding the appropriate agent behavior is a cumbersome task – no matter whether it is for agent-based software or simulation models. Machine Learning can help by generating partial or preliminary versions of the agent low-level behavior. However, for actually being useful for the human modeler the results should be interpretable, which may require some post-processing step after the actual behavior learning. In this contribution we test the sensitivity of the resulting, interpretable behavior program with respect to parameters and components of the function that describes the intended behavior.

  • 177.
    Junges, Robert
    et al.
    Örebro University, School of Science and Technology.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    How to design agent-based simulation models using agent learning2012In: Winter Simulation Conference Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2012, p. 1-10Conference paper (Refereed)
    Abstract [en]

    The question of what is the best way to develop an agent-based simulation model becomes more important as this paradigm is more and more used. Clearly, general model development processes can be used, but these do not solve the major problems of actually deciding about the agents' structure and behavior. In this contribution we introduce the MABLe methodology for analyzing and designing agent simulation models that relies on adaptive agents, where the agent helps the modeler by proposing a suitable behavior program. We test our methodology in a pedestrian evacuation scenario. Results demonstrate the agents can learn and report back to the modeler a behavior that is interestingly better than a hand-made model.

    Download full text (pdf)
    WCS2012 Design by Learning
  • 178.
    Junges, Robert
    et al.
    Örebro University, School of Science and Technology.
    Klügl, Franziska
    Örebro University, School of Science and Technology.
    Programming agent behavior by learning in simulation models2012In: Applied Artificial Intelligence, ISSN 0883-9514, E-ISSN 1087-6545, Vol. 26, no 4, p. 349-375Article in journal (Refereed)
    Abstract [en]

    Designing the proper agent behavior for a multiagent system is a complex task. Often it is not obvious which of the agents' actions, and the interactions among them and with their environment, can produce the intended macro-phenomenon. We assume that the modeler can benefit from using agent-learning techniques. There are several issues with which learning can help modeling; for example, by using self-adaptive agents for calibration. In this contribution we are dealing with another example: the usage of learning for supporting system analysis and model design. A candidate-learning architecture is the combination of reinforcement learning and decision tree learning. The former generates a policy for agent behavior and the latter is used for abstraction and interpretation purposes. Here, we focus on the relation between policy-learning convergence and the quality of the abstracted model produced from that.

  • 179.
    Kadmiry, Bourhane
    et al.
    Linköping University, Linköping, Sweden.
    Driankov, Dimiter
    Linköping University, Linköping, Sweden.
    Fuzzy control of an autonomous helicopter2001In: Joint 9th IFSA World Congress and 20th NAFIPS International Conference / [ed] Smith, M.H., Gruver, W.A. & Hall, L.O., New York, USA: IEEE conference proceedings, 2001, p. 2797-2802Conference paper (Refereed)
    Abstract [en]

    This work presents a horizontal velocity controller for the unmanned helicopter APID MK-III developed by Scandicraft AB in Sweden. We use a novel approach to the design consisting of two steps: 1) Mamdani-type of fuzzy rules to compute each of the desired horizontal velocity corresponding to the desired values for the attitude angles and the main rotor collective pitch; and 2) a Takagi-Sugeno controller is used to regulate the attitude angles so that the helicopter achieves its desired horizontal velocities at a desired altitude. The performance of the combined linguistic/model-based controller is evaluated in simulation and shows that the proposed design method achieves its intended purpose

  • 180.
    Kadmiry, Bourhane
    et al.
    Linköping University, Linköping, Sweden.
    Driankov, Dimiter
    Örebro University, School of Science and Technology.
    Takagi-Sugeno fuzzy gain scheduling with sampling-time uncertainties2004In: Proceedings 2004 IEEE International Conference on Fuzzy Systems, New York, USA: IEEE conference proceedings, 2004, Vol. 2, p. 1087-1091Conference paper (Refereed)
    Abstract [en]

    This paper addresses the robust fuzzy control problem for discrete-time nonlinear systems in the presence of sampling time uncertainties. The case of the discrete T-S fuzzy system with sampling-time uncertainty is considered and a robust controller design method is proposed. The sufficient conditions and the design procedure are formulated in the form of linear matrix inequalities (LMI). The effectiveness of the proposed controller design methodology is demonstrated of a visual-servoing control problem.

  • 181.
    Kajtazi, Miranda
    et al.
    Lund University, Lund, Sweden.
    Haftor, Darek
    Institutionen för datavetenskap, fysik och matematik (DFM), Linnéuniversitetet, Växjö, Sweden.
    Information Inadequacy: Instances that Causes the Lack of Needed Information2012In: The 5th Workshop on Information Logistics and Knowledge Supply (ILOG2012), at the 11th International Conference on Perspectives in Business Informatics Research (BIR2012): Nizhny Novgorod, Russia, September 24-26, 2012. Proceedings: “Satellite Workshops & Doctoral Consortium.”, Springer, 2012, p. 7-17Conference paper (Refereed)
  • 182.
    Kalaykov, Ivan
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Iliev, Boyko
    Örebro University, School of Science and Technology.
    SME robotics demand flexible grippers and fixtures2008In: Proc. 39th Int. Symposium on Robotics, Seoul, Korea, 2008, p. 62-65Conference paper (Refereed)
  • 183.
    Kalaykov, Ivan
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani
    Örebro University, School of Science and Technology.
    Iliev, Boykov
    Örebro University, School of Science and Technology.
    Flexible grippers and fixtures2008Conference paper (Refereed)
  • 184.
    Kaltenhaeuser, Robert
    et al.
    Ilmenau University of Technology, Ilmenau, Germany.
    Schaffernicht, Erik
    Örebro University, School of Science and Technology.
    Steege, Frank-Florian
    Ilmenau University of Technology, Ilmenau, Germany.
    Gross, Horst-Michael
    Ilmenau University of Technology, Ilmenau, Germany.
    Evolutionary computation based system decomposition with neural networks2013In: ESANN 2013 proceedings, European Symposium on Artificial Neural Networks, Computational Intelligenceand Machine Learning, Louvain-La-Neuve: ESANN , 2013, p. 191-196Conference paper (Refereed)
    Abstract [en]

    We present an evolutionary approach to divide a complex control system into smaller sub-systems with the help of neural networks.Thereto, measured channels are partitioned into several disjunct sets, rep-resenting possible sub-problems, while the networks are used to assessthe quality of the resulting decomposition. We show that this approach iswell suited to calculate correct decompositions of complex control systems.Furthermore, the obtained neural networks are used to predict importantprocess factors with considerable better approximation quality than mono-lithic approaches that have to deal with all input channels in parallel.

  • 185.
    Karlsson, Tobias
    et al.
    Örebro University, School of Science and Technology.
    Linnér, Jakob
    Örebro University, School of Science and Technology.
    Avfyrnings-/relälåda2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a report of our examination project in electronics carried out for Bofors Test Center in Karlskoga. The task was to construct an electronic devise for starting up different kinds of measuring systems in exact time during test sequences. The modules that are used today are old and unreliable. Our goal was to construct a prototype, which later on is supposed to be developed into a useful system.

    Download full text (pdf)
    FULLTEXT01
  • 186.
    KHALIQ, ALI ABDUL
    Örebro University, School of Science and Technology.
    Gas Dispersal Simulation in ROS2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work presents a 3-D gas dispersal simulation and olfactory detection system

    implemented in ROS. Gas dispersal simulation integrates OpenFOAMflow

    simulation and a filament-based gas propagation model to simulate gas dispersion

    for compressible flows with a realistic turbulence model. The olfactory

    detection system models the response of metal oxide gas sensor to the simulated

    gas.

    Olfaction related experiments in mobile robots can be highly complex and

    hazardous due to the involvement of flammable and toxic gases. Moreover, the

    results of mobile olfaction task depends on the characteristics of environment

    and on the characteristics of odor detection system. The precision of results of

    this task is usually effected due to the variability of interrelationships between

    these characteristics which can create complications to focus on task aspect.

    The motivation behind the development of this simulation package is to make

    environment and odor detection system controllable, where experiments can

    be repeated under identical conditions, bypassing the environmental hazards

    so that the research work can concentrate on task aspect.

    The simulation package is validated through the results obtained by various

    tests including constant concentrations in ideal conditions as well as changing

    concentration in turbulent environment.

    i

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    fulltext
  • 187.
    Khodadad, Davood
    Örebro University, School of Science and Technology. Experimental Mechanics, Luleå University of Technology, Luleå, Sweden .
    Phase-derivative-based estimation of a digital reference wave from a single off-axis digital hologram2016In: Applied Optics, ISSN 1559-128X, E-ISSN 2155-3165, Vol. 55, no 7, p. 1663-1669Article in journal (Refereed)
    Abstract [en]

    This paper describes a method to obtain an estimated digital reference wave from a single off-axis digital hologram that matches the actual experimental reference wave as closely as possible. The proposed method is independent of a reference flat plate and speckles. The digital reference wave parameters are estimated directly from the recorded phase information. The parameters include both the off-axis tilt angle and the curvature of the reference wave. Phase derivatives are used to extract the digital reference wave parameters without the need for a phase unwrapping process. Thus, problems associated with phase wrapping are avoided. Experimental results for the proposed method are provided. The simulated effect of the digital reference wave parameters on the reconstructed image phase distribution is shown. The pseudo phase gradient originating from incorrect estimation of the digital reference wave parameters and its effect on object reconstruction are discussed.

  • 188.
    Khodadad, Davood
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Amer, Eynas
    Luleå University of Technology, Luleå, Sweden.
    Gren, Per
    Luleå University of Technology, Luleå, Sweden.
    Melander, Emil
    Uppsala University, Uppsala, Sweden.
    Hällstig, Emil
    Fotonic, Stockholm, Sweden.
    Sjödahl, Mikael
    Luleå University of Technology, Luleå, Sweden.
    Single-shot dual-polarization holography: measurement of the polarization state of a magnetic sample2015In: VI International Conference on Speckle Metrology, SPIE - International Society for Optical Engineering, 2015, Vol. 9660, article id 96601EConference paper (Refereed)
    Abstract [en]

    In this paper a single-shot digital holographic set-up with two orthogonally polarized reference beams is proposed to achieve rapid acquisition of Magneto-Optical Kerr Effect images. Principles of the method and the background theory for dynamic state of polarization measurement by use of digital holography are presented. This system has no mechanically moving elements or active elements for polarization control and modulation. An object beam is combined with two reference beams at different off-axis angles and is guided to a detector. Then two complex fields (interference terms) representing two orthogonal polarizations are recorded in a single frame simultaneously. Thereafter the complex fields are numerically reconstructed and carrier frequency calibration is done to remove aberrations introduced in multiplexed digital holographic recordings. From the numerical values of amplitude and phase, a real time quantitative analysis of the polarization state is possible by use of Jones vectors. The technique is demonstrated on a magnetic sample that is a lithographically patterned magnetic microstructure consisting of thin permalloy parallel stripes.

  • 189.
    Khodadad, Davood
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Bergström, Per
    Luleå University of Technology, Luleå, Sweden.
    Hällstig, Emil
    Optronic, Skellefteå, Sweden.
    Sjödahl, Mikael
    Luleå University of Technology, Luleå, Sweden.
    Dual-wavelength digital holography: single shot calibration2014In: Interferometry XVII: Techniques and Analysis / [ed] Katherine Creath, Jan Burke & Joanna Schmit, SPIE - International Society for Optical Engineering, 2014, Vol. 9203, article id 920305Conference paper (Refereed)
    Abstract [en]

    In an on line shape measurement in disturbed environment, use of many wavelengths in order to avoid phase ambiguity may become a problem as it is necessary to acquire all holograms simultaneously due to environmental disturbances. Therefore to make the shape data available the different holograms have to be extracted from a single recorded image in spectral domain. Appropriate cut areas in the Fourier method are therefore of great importance for decoding information carried by different wavelengths. Furthermore using different laser sources, induces aberration and pseudo phase changes which must be compensated. To insure any phase change is only because of the object shape, calibration is therefore indispensable. For this purpose, effects of uncontrolled carrier frequency filtering are discussed. A registration procedure is applied using minimum speckle displacements to find the best cut area to extract and match the interference terms. Both holograms are numerically propagated to a focus plane to avoid any unknown errors. Deviations between a reference known plate and its measurement are found and used for calibration. We demonstrate that phase maps and speckle displacements can be recovered free of chromatic aberrations. To our knowledge, this is the first time that a single shot dual wavelength calibration is reported by defining a criteria to make the spatial filtering automatic avoiding the problems of manual methods. The procedure is shown to give shape accuracy of 35ÎŒm with negligible systematic errors using a synthetic wavelength of 1.1 mm.

  • 190.
    Khodadad, Davood
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Hallstig, Emil J.
    Optronic, Skellefteå, Sweden.
    Sjödahl, Mikael
    Luleå University of Technology, Luleå, Sweden.
    Dual-wavelength digital holographic shape measurement using speckle movements and phase gradients2013In: Optical Engineering: The Journal of SPIE, ISSN 0091-3286, E-ISSN 1560-2303, Vol. 52, no 10, article id 101912Article in journal (Refereed)
    Abstract [en]

    A new method to measure shape by analyzing the speckle movements in images generated by numerical propagation from dual-wavelength holograms is presented. The relationship of the speckle movements at different focal distances is formulated, and it is shown how this carries information about the surface position as well as the local slope of the object. It is experimentally verified that dual-wavelength holography and numerically generated speckle images can be used together with digital speckle correlation to retrieve the object shape. From a measurement on a cylindrical test object, the method is demonstrated to have a random error in the order of a few micrometers.

  • 191.
    Khodadad, Davood
    et al.
    Department of Physics and Electrical Engineering, Linnaeus University, Växjö, Sweden.
    Nordebo, Sven
    Department of Physics and Electrical Engineering, Linnaeus University, Växjö, Sweden.
    Seifnaraghi, Nima
    Faculty of science and technology, Middlesex University, Hendon campus, The Burroughs, London, United Kingdom.
    Waldmann, Andreas D.
    Swisstom AG, Landquart, Switzerland.
    Müller, Beat
    Swisstom AG, Landquart, Switzerland.
    Bayford, Richard
    Faculty of science and technology, Middlesex University, Hendon campus, The Burroughs, London, United Kingdom.
    Breath detection using short-time Fourier transform analysis in electrical impedance tomography2017In: 2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS), IEEE, 2017, p. 1-3Conference paper (Refereed)
    Abstract [en]

    Spectral analysis based on short-time Fourier transform (STFT) using Kaiser window is proposed to examine the frequency components of neonates EIT data. In this way, a simultaneous spatial-time-frequency analysis is achieved.

  • 192.
    Khodadad, Davood
    et al.
    Department of Physics and Electrical Engineering, Linnaeus University, Växjö, Sweden.
    Nordebo, Sven
    Department of Physics and Electrical Engineering, Linnaeus University, Växjö, Sweden.
    Seifnaraghi, Nima
    Department of Natural Sciences, Middlesex University, Hendon Campus, The Burroughs, London, United Kingdom.
    Yerworth, Rebecca
    Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.
    Waldmann, Andreas D.
    Swisstom AG, Landquart, Switzerland.
    Müller, Beat
    Swisstom AG, Landquart, Switzerland.
    Frerichs, Inéz
    Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre Schleswig-Holstein, Campus Kiel, Kiel, Germany.
    van Kaam, Anton
    Emma Children's Hospital, Academic Medical Center, Department of Neonatology, Amsterdam, The Netherlands.
    Miedema, Martijn
    Emma Children's Hospital, Academic Medical Center, Department of Neonatology, Amsterdam, The Netherlands.
    Bayford, Richard
    Department of Natural Sciences, Middlesex University, Hendon Campus, The Burroughs, London, United Kingdom.
    The Value of Phase Angle in Electrical Impedance Tomography Breath Detection2018In: 2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama), Electromagnetics Academy , 2018, p. 1040-1043Conference paper (Refereed)
    Abstract [en]

    The objective of this paper is to report our investigation demonstrating that the phase angle information of complex impedance could be a simple indicator of a breath cycle in chest Electrical Impedance Tomography (EIT). The study used clinical neonatal EIT data. The results show that measurement of the phase angle from complex EIT data can be used as a complementary information for improving the conventional breath detection algorithms.

  • 193.
    Khodadad, Davood
    et al.
    Department of Physics and Electrical Engineering, Linnaeus University, Växjö, Sweden.
    Tayebi, Behnam
    Department of Brain and Cognitive Engineering, Korea University, Seoul, South Korea.
    Shape Measurement Based on Combined Reduced Phase Dual-Directional Illumination Digital Holography and Speckle Displacements2018In: 2018 Progress in Electromagnetics Research Symposium (PIERS-Toyama), Electromagnetics Academy , 2018, p. 184-189Conference paper (Refereed)
    Abstract [en]

    We present a dual-directional illumination digital holographic method to increase height range measurement with a reduced phase ambiguity. Small change in the illumination angle of incident introduce phase difference between the recorded complex fields. We decrease relative phase difference between the recorded complex field 279 and 139 times by changing the angle of incident 0.5° and 1°, respectively. A two cent Euro coin edge groove is used to measure the shape. The groove depth is measured as ≈ 300μm. Further, numerical re-focusing and analysis of speckle displacements in two different planes are used to measure the depth without a use of phase unwrapping process.

  • 194.
    Kiselev, Andrey
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Sivakumar, Prasanna Kumar
    SASTRA University, Thanjavur, India.
    Swaminathan, Chittaranjan Srinivas
    SASTRA University, Thanjavur, India.
    Robot-human hand-overs in non-anthropomorphic robots2013In: Proceedings of the 8th ACM/IEEE International Conference on Human-Robot Interaction, HRI'13 / [ed] Hideaki Kuzuoka, Vanessa Evers, Michita Imai, Jodi Forlizzi, IEEE Press, 2013, p. 227-228Conference paper (Refereed)
    Abstract [en]

    Robots that assist and interact with humans will inevitably require to successfully achieve the task of handing over objects. Whether it is to deliver desired objects for the elderly living in their homes or hand tools to a worker in a factory, the process of robot hand-overs is one worthy study within the human robot interaction community. While the study of object hand-overs have been studied in previous works, these works have mainly considered anthropomorphic robots, that is, robots that appear and move similar to humans. However, recent trends within robotics, and in particular domestic robotics have witnessed an increase in non-anthropomorphic robotic platforms such as moving tables, teleconferencing robots and vacuum cleaners. The study of robot hand-over for nonanthropomorphic robots and in particular the study of what constitute a successful hand-over is at focus in this paper. For the purpose of investigation, the TurtleBot, which is a moving table like device is used in a home environment.

  • 195.
    Kiselev, Andrey
    et al.
    Örebro University, School of Science and Technology.
    Potenza, Andre
    Örebro University, School of Science and Technology.
    Bruno, Barbara
    DIBRIS, University Genova, Genova, Italy.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Towards Seamless Autonomous Function Handovers in Human-Robot Teams2017Conference paper (Refereed)
    Abstract [en]

    Various human-robot collaboration scenarios mayimpose different requirements on the robot’s autonomy, ranging from fully autonomous to fully manual operation. The paradigm of sliding autonomy has been introduced to allow adapting robots’ autonomy in real time, thus improving flexibility of a human-robot team. In sliding autonomy, functions can be handed over between the human and the robot to address environment changes and optimize performance and workload. This paper examines the process of handing over functions between humans by looking at a particular experiment scenario in which the same function has to be handed over multiple times during the experiment session. We hypothesize that the process of function handover is similar to already well-studied human-robot handovers which deal with physical objects. In the experiment, we attempt to discover natural similarities and differences between these two types of handovers and suggest further directions of work that are necessary to give the robot the ability to perform the function handover autonomously, without explicit instruction from the human counterpart.

  • 196.
    Kiselev, Andrey
    et al.
    Örebro University, School of Science and Technology.
    Scherlund, Mårten
    Giraff Technologies AB, Västerås, Sweden.
    Kristoffersson, Annica
    Örebro University, School of Science and Technology.
    Efremova, Natalia
    Plekhanom University, Moscow, Russia.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Auditory immersion with stereo sound in a mobile robotic telepresence system2015In: 10th ACM/IEEE International Conference on Human-Robot Interaction, 2015, Association for Computing Machinery (ACM), 2015Conference paper (Refereed)
    Abstract [en]

    Auditory immersion plays a significant role in generating a good feeling of presence for users driving a telepresence robot. In this paper, one of the key characteristics of auditory immersion - sound source localization (SSL) - is studied from the perspective of those who operate telepresence robots from remote locations. A prototype which is capable of delivering soundscape to the user through Interaural Time Difference (ITD) and Interaural Level Difference (ILD) using the ORTF stereo recording technique was developed. The prototype was evaluated in an experiment and the results suggest that the developed method is sufficient for sound source localization tasks.

    Download full text (pdf)
    Auditory Immersion with Stereo Sound in a Mobile Robotic Telepresence System
  • 197.
    Klügl, Franziska
    et al.
    Örebro University, School of Science and Technology.
    Bernon, Carole
    Paul Sabatier University, Toulouse, France.
    Self-Adaptive Agents for Debugging Multi-Agent Simulations2011In: Proc. of the 3rd ADAPTIVE 2011: The Third International Conference on Adaptive and Self-Adaptive Systems and Applications / [ed] J. Fox and A. Rausch, Xpert Publishing Services, 2011, p. 79-84Conference paper (Refereed)
    Abstract [en]

    In this contribution, we propose an adaptation-drivenmethodology for the technical design and implementation of multi-agent simulations that is inspired by the concept of "living design". The simulated agents are capable of evaluatingtheir behavior and self-adapt for improving the overall model.For this aim, the modeler describes critical, non valid situations in the life of an agent, or the complete agent system, and explicitly specifies repair knowledge for these situations.

    Download full text (pdf)
    ADAPTIVE2011_KluglBernon
  • 198.
    Klügl, Franziska
    et al.
    Örebro University, School of Science and Technology.
    Karlsson, Lars
    Örebro University, School of Science and Technology.
    Towards Pattern-Oriented Design of Agent-Based Simulation Models2009In: MULTI-AGENT SYSTEM TECHNOLOGIES, PROCEEDINGS / [ed] Braubach, L; VanderHoek, W; Petta, P; Pokahr, A, Berlin, Germany: Springer, 2009, p. 41-53Conference paper (Refereed)
    Abstract [en]

    The formalization and use of experiences in good model design would make an important contribution to increasing the efficiency of modeling as well as to supporting the knowledge transfer from experienced modelers to modeling novices. We propose to address this problem by providing a set of model design patterns inspired by patterns in Software Engineering for capturing the reusable essence of a solution to specific partial modeling problem. This contribution provides a First step formulating the vision and indicating how patterns and which types of patterns can play a role in agent-based model design.

  • 199.
    Klügl, Franziska
    et al.
    Örebro University, School of Science and Technology.
    Ossowski, SaschaUniversity Rey Juan Carlos, Madrid, Spain.
    Multiagent system technologies: 9th German Conference, MATES 2011, Berlin, Germany, October 6-7, 2011. Proceedings2011Conference proceedings (editor) (Refereed)
    Abstract [en]

    This book constitutes the proceedings of the 9th German Conference on Multiagent System Technologies held in Berlin, Germany, in October 2011. The 12 revised full papers presented together with 6 short parers were carefully reviewed and selected from 50 submissions. Providing an interdisciplinary forum for researchers, users, and developers to present and discuss latest advances in research work as well as prototyped or fielded systems of intelligent agents and multi-agent systems, the papers cover the whole range of this sector and promote its theory and applications.

  • 200.
    Klügl, Franziska
    et al.
    Örebro University, School of Science and Technology.
    Rindsfüser, Guido
    Emch&Berger AG, Bern, Switzerland.
    Agent-based route (and mode) choice simulation in real-world networks2011In: 2011 IEEE/WIC/ACM International Conference on  Web Intelligence and Intelligent Agent Technology (WI-IAT) / [ed] Jomi F. Hübner, Jean-Marc Petit, Einoshin Suzuki, IEEE, 2011, p. 22-29Conference paper (Refereed)
    Abstract [en]

    Mode and route choice are central elements of traffic simulations. Traditionally they form two subsequent steps in the four-step process where first, the simulated population distributes among available transportation modes and then their movement is assigned to the roads respectively other networks. However, these two phases are better dealt with simultaneously as choices are highly depending on each other. In this paper, we are suggesting an agent-based combined route and mode choice model that is not only able to resemble traditional simulations, but provides the means for new applications. As the simulated agents are active and situated while moving through the network, they are able to react to unforeseen events such as the closing of a link. Thus we can reproduce the self-organized re-distribution of travelers to new routes depending on when/where they are notified about the problem. We illustrate the feasibility and usefulness of our agent-based mode and route choice simulation using a real-world network of a small-size Swiss town.

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