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  • 51.
    Dimopoulos, A.
    et al.
    Natl Tech Univ Athens, Dept Mech Engn, Athens 15780, Greece.
    Papadopoulos, E.
    Natl Tech Univ Athens, Dept Mech Engn, Athens 15780, Greece.
    Iagnemma, Karl
    MIT, USA.
    Experimental tissue parameter identification for use in endoscopic urological haptic simulators2009Ingår i: Control and Automation, 2009. MED ’09. 17th Mediterranean Conference on, Piscataway, N.J.: IEEE Press, 2009, s. 1131-1136Konferensbidrag (Refereegranskat)
    Abstract [en]

    A method is developed for obtaining parameters for tube-like soft-tissues, to be used in urological haptic simulators. A device was designed and built that allows the acquisition of forces and displacements during endoscope insertion in a tubelike soft tissue. The device consists of a mechatronic ball screw mechanism, with a 6 DOF force/ torque sensor attached to it. The steel shaft representing the endoscope, is commanded to follow desired trajectories with micrometric accuracy under the application of an IPD controller, implemented on a dSpace 1103 system. The experimental data acquired is fitted to polynomials to yield a tissue model that can be used to predict insertion forces required for haptic simulator feedback.

  • 52.
    Dubowsky, S.
    et al.
    MIT, USA.
    Iagnemma, Karl
    MIT, USA.
    Liberatore, S.
    MIT, USA.
    Lambeth, D. M.
    MIT, USA.
    Plante, J. S.
    MIT, USA.
    Boston, P. J.
    New Mexico Tech. NM Institute of Mining and Technology, Socorro, NM 87801, United States.
    A concept mission: Microbots for large-scale planetary surface and subsurface exploration2005Ingår i: Space technology and applications international forum: STAIF 2005 / [ed] Mohamed S El-Genk, College Park, MD: American Institute of Physics (AIP), 2005, s. 1449-1458Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a new mission concept for planetary exploration, based on the deployment of a large number of small spherical mobile robots ("microbots") over vast areas of a planet's surface and subsurface, including structures such as caves and near-surface crevasses (see Figure 1). This would allow extremely large-scale in situ analysis of terrain composition and history. This approach represents an alternative to rover and lander-based planetary exploration, which is limited to studying small areas of a planet's surface at a small number of sites. The proposed approach is also distinct from balloon or aerial vehicle-based missions, in that it would allow direct in situ measurement. In the proposed mission, a large number (i.e. hundreds or thousands) of cm-scale, sub-kilogram microbots would be distributed over a planet's surface by an orbital craft and would employ hopping, bouncing and rolling as a locomotion mode to reach scientifically interesting artifacts in very rugged terrain. They would be powered by high energy-density polymer "muscle" actuators, and equipped with a suite of miniaturized imagers, spectrometers, sampling devices, and chemical detection sensors to conduct in situ measurements of terrain and rock composition, structure, etc. Multiple microbots would coordinate to share information, cooperatively analyze large portions of a planet's surface or subsurface, and provide context for scientific measurements. © 2005 American Institute of Physics.

  • 53.
    Durán, Boris
    et al.
    RISE Viktoria, Gothenburg, Sweden.
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). RISE Viktoria, Gothenburg, Sweden.
    Habobovic, Azra
    RISE Viktoria, Gothenburg, Sweden.
    Andersson, Jonas
    RISE Viktoria, Gothenburg, Sweden.
    Modeling vehicle behavior with neural dynamics2017Ingår i: Future Active Safety Technology - Towards zero traffic accidents, Nara, Japan, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Modeling the interaction of vehicles during certain traffic situations is the starting point for creating autonomous driving. Data collected from field trials where test subjects drive through a single-vehicle intersection was used to create behavioral models. The present work describes two implementations of models based on the dynamical systems approach and compares similarities and differences between them. The proposed models are designed to closely replicate the behavior selection in the intersection crossing experiment.

  • 54.
    Englund, Cristofer
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). Viktoria Swedish ICT, Gothenburg, Sweden.
    Chen, Lei
    Viktoria Swedish ICT, Gothenburg, Sweden.
    Ploeg, Jeroen
    Netherlands Organization for Applied Scientific Research TNO, Hague, Netherlands.
    Semsar-Kazerooni, Elham
    Netherlands Organization for Applied Scientific Research TNO, Hague, Netherlands.
    Voronov, Alexey
    Viktoria Swedish ICT, Gothenburg, Sweden.
    Hoang Bengtsson, Hoai
    Viktoria Swedish ICT, Gothenburg, Sweden.
    Didoff, Jonas
    Viktoria Swedish ICT, Gothenburg, Sweden.
    The Grand Cooperative Driving Challenge 2016: Boosting the Introduction of Cooperative Automated Vehicles2016Ingår i: IEEE wireless communications, ISSN 1536-1284, E-ISSN 1558-0687, Vol. 23, nr 4, s. 146-152Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Grand Cooperative Driving Challenge (GCDC), with the aim to boost the introduction of cooperative automated vehicles by means of wireless communication, is presented. Experiences from the previous edition of GCDC, which was held in Helmond in the Netherlands in 2011, are summarized, and an overview and expectations of the challenges in the 2016 edition are discussed. Two challenge scenarios, cooperative platoon merge and cooperative intersection passing, are specified and presented. One demonstration scenario for emergency vehicles is designed to showcase the benefits of cooperative driving. Communications closely follow the newly published cooperative intelligent transport system standards, while interaction protocols are designed for each of the scenarios. For the purpose of interoperability testing, an interactive testing tool is designed and presented. A general summary of the requirements on teams for participating in the challenge is also presented.

  • 55.
    Englund, Cristofer
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). RISE Viktoria, Gothenburg, Sweden.
    Didoff, Jonas
    RISE Viktoria, Gothenburg, Sweden.
    Wahlström, Björn
    Swedish Aviation Services, Norrköping, Sweden.
    A new method for ground vehicle access control and situation awareness: experiences from a real-life implementation at an airport2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    To improve safety in complex traffic situations, access control can be applied. This paper presents a generic vehicle access control method for improved situation awareness. The method concerns three main steps (i) zones definition (ii) rules to manage access and (iii) situation awareness based on realtime position monitoring. The proposed system consists of a server where the access zones and rules are stored and mobile units providing position data to the server and information to the driver. At the control center a client control unit is used to provide improved situation awareness by monitoring and visualizing the positions of the clients in the vehicles. The client in the control center is also utilized to give access to the clients in the vehicles that request access. The system has been demonstrated at an airport to grant access for ground vehicles to enter the runway and has since been developed into a commercial product by an industrial supplier. It was introduced at the World ATM Congress in Madrid in March of 2017. The server system is implemented as a cloud service in Microsoft Azure, the control client uses a WACOM CINTIQ touch screen computer for interaction and the vehicle clients are off-the-shelf Samsung Android units paired with Trimble R1GNSS receiver and 4G mobile communication between the server and the clients.

  • 56.
    Englund, Cristofer
    et al.
    RISE Viktoria, Göteborg, Sweden.
    Estrada, John
    eTrans Systems, Fairfax, USA.
    Jaaskelainen, Juhani
    MH Roine Consulting, Helsinki, Finland.
    Meisner, Jim
    Qualcomm Technologies Inc., San Diego, USA.
    Satyavolu, Surya
    Sirab Technologies Inc., Novato, USA.
    Serna, Frank
    Draper Laboratory, 555 Technology Square, Cambridge, USA.
    Sundararajan, Sudharson
    Booz Allen Hamilton Inc., Washington, USA.
    Enabling Technologies for Road Vehicle Automation2017Ingår i: Road Vehicle Automation 4 / [ed] Meyer G. & Beiker S., Leiden: VSP , 2017, s. 177-185Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Technology is to a large extent driving the development of road vehicle automation. This Chapter summarizes the general overall trends in the enabling technologies within this field that were discussed during the Enabling technologies for road vehicle automation breakout session at the Automated Vehicle Symposium 2016. With a starting point in six scenarios that have the potential to be deployed at an early stage, five different categories of emerging technologies are described: (a) positioning, localization and mapping (b) algorithms, deep learning techniques, sensor fusion guidance and control (c) hybrid communication (d) sensing and perception and (e) technologies for data ownership and privacy. It is found that reliability and extensive computational power are the two most common challenges within the emerging technologies. Furthermore, cybersecurity binds all technologies together as vehicles will be constantly connected. Connectivity allows both improved local awareness through vehicle-to-vehicle communication and it allows continuous deployment of new software and algorithms that constantly learns new unforeseen objects or scenarios. Finally, while five categories were individually considered, further holistic work to combine them in a systems concept would be the important next step toward implementation. © Springer International Publishing AG 2018

  • 57.
    Ericson, Stefan K.
    et al.
    University of Skövde, Skövde, Sweden.
    Åstrand, Björn
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Analysis of two visual odometry systems for use in an agricultural field environment2018Ingår i: Biosystems Engineering, ISSN 1537-5110, E-ISSN 1537-5129, Vol. 166, s. 116-125Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper analyses two visual odometry systems for use in an agricultural field environment. The impact of various design parameters and camera setups are evaluated in a simulation environment. Four real field experiments were conducted using a mobile robot operating in an agricultural field. The robot was controlled to travel in a regular back-and-forth pattern with headland turns. The experimental runs were 1.8–3.1 km long and consisted of 32–63,000 frames. The results indicate that a camera angle of 75° gives the best results with the least error. An increased camera resolution only improves the result slightly. The algorithm must be able to reduce error accumulation by adapting the frame rate to minimise error. The results also illustrate the difficulties of estimating roll and pitch using a downward-facing camera. The best results for full 6-DOF position estimation were obtained on a 1.8-km run using 6680 frames captured from the forward-facing cameras. The translation error (x, y, z) is 3.76% and the rotational error (i.e., roll, pitch, and yaw) is 0.0482 deg m−1. The main contributions of this paper are an analysis of design option impacts on visual odometry results and a comparison of two state-of-the-art visual odometry algorithms, applied to agricultural field data. © 2017 IAgrE

  • 58.
    Ericson, Stefan
    et al.
    School of Technology and Society, University of Skövde, Skövde.
    Åstrand, Björn
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Row-detection on an agricultural field using omnidirectional camera2010Ingår i: 2010 IEEE/RSJ international conference on intelligent robots and systems, Piscataway, N.J.: IEEE Press, 2010, s. 4982-4987Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes a method of detecting parallel rows on an agricultural field using an omnidirectional camera. The method works both on cameras with a fisheye lens and cameras with a catadioptric lens. A combination of an edge based method and a Hough transform method is suggested to find the rows. The vanishing point of several parallel rows is estimated using a second Hough transform. The method is evaluated on synthetic images generated with calibration data from real lenses. Scenes with several rows are produced, where each plant is positioned with a specified error. Experiments are performed on these synthetic images and on real field images. The result shows that good accuracy is obtained on the vanishing point once it is detected correctly. Further it shows that the edge based method works best when the rows consists of solid lines, and the Hough method works best when the rows consists of individual plants. The experiments also show that the combined method provides better detection than using the methods separately.

  • 59.
    Fan, Yuantao
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Aramrattana, Maytheewat
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Shahbandi, Saeed Gholami
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Nemati, Hassan Mashad
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Åstrand, Björn
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Infrastructure Mapping in Well-Structured Environments Using MAV2016Ingår i: Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349, Vol. 9716, s. 116-126Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we present a design of a surveying system for warehouse environment using low cost quadcopter. The system focus on mapping the infrastructure of surveyed environment. As a unique and essential parts of the warehouse, pillars from storing shelves are chosen as landmark objects for representing the environment. The map are generated based on fusing the outputs of two different methods, point cloud of corner features from Parallel Tracking and Mapping (PTAM) algorithm with estimated pillar position from a multi-stage image analysis method. Localization of the drone relies on PTAM algorithm. The system is implemented in Robot Operating System(ROS) and MATLAB, and has been successfully tested in real-world experiments. The result map after scaling has a metric error less than 20 cm. © Springer International Publishing Switzerland 2016.

  • 60.
    Fatnassi, Eddi
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Modväxlare2019Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta projekt handlar om att effektivisera EMC-testning genom att undersöka hur en modväxlare konstrueras samt hur denna styrs och ifall det behövs återkoppling för denna ska uppnå funktionell nivå. Syftet med modväxlare är att man enklare ska kunna testa emissions- och immunitetsnivåer av nya tekniska uppfinningar och på så sätt värna om framtidens elektromagnetiska milj¨o. Under arbetets g˚ang har en modv¨axlare designats med CAD varpå modellen har skalats ner för att testa positionsnogrannhet, acceleration och tidsåtgång för körning. Avslutningsvis har man dragit slutsatser baserat på testerna och med hjälp av dessa framfört anvisningar till hur en fullskalig modväxlare bör konstrueras.

  • 61.
    Gholami Shahbandi, Saeed
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Interpretation and Alignment of 2D Indoor Maps: Towards a Heterogeneous Map Representation2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Mobile robots are increasingly being used in automation solutions with notable examples in service robots, such as home-care, and warehouses. Autonomy of mobile robots is particularly challenging, since their work space is not deterministic, known a priori, or fully predictable. Accordingly, the ability to model the work space, that is robotic mapping, is among the core technologies that are the backbone of autonomous mobile robots. However, for some applications the abilities of mapping and localization do not meet all the requirements, and robots with an enhanced awareness of their surroundings are desired. For instance, a map augmented with semantic labels is instrumental to support Human-Robot Interaction and high-level task planning and reasoning.This thesis addresses this requirement through an interpretation and integration of multiple input maps into a semantically annotated heterogeneous representation. The heterogeneity of the representation should to contain different interpretations of an input map, establish and maintain associations among different input sources, and construct a hierarchy of abstraction through model-based representation. The structuring and construction of this representation are at the core of this thesis, and the main objectives are: a) modeling, interpretation, semantic annotation, and association of the different data sources into a heterogeneous representation, and b) improving the autonomy of the aforementioned processes by curtailing the dependency of the methods on human input, such as domain knowledge.This work proposes map interpretation techniques, such as abstract representation through modeling and semantic annotation, in an attempt to enrich the final representation. In order to associate multiple data sources, this work also proposes a map alignment method. The contributions and general observations that result from the studies included in this work could be summarized as: i) manner of structuring the heterogeneous representation, ii) underlining the advantages of modeling and abstract representations, iii) several approaches to semantic annotation, and iv) improved extensibility of methods by lessening their dependency on human input.The scope of the work has been focused on 2D maps of well-structured indoor environments, such as warehouses, home, and office buildings.

  • 62.
    Gholami Shahbandi, Saeed
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Semantic Mapping in Warehouses2016Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis and appended papers present the process of tacking the problem of environment modeling for autonomous agent. More specifically, the focus of the work has been semantic mapping of warehouses. A semantic map for such purpose is expected to be layout-like and support semantics of both open spaces and infrastructure of the environment. The representation of the semantic map is required to be understandable by all involved agents (humans, AGVs and WMS.) And the process of semantic mapping is desired to lean toward full-autonomy, with minimum input requirement from human user. To that end, we studied the problem of semantic annotation over two kinds of spatial map from different modalities. We identified properties, structure, and challenges of the problem. And we have developed representations and accompanied methods, while meeting the set criteria. The overall objective of the work is “to develop and construct a layer of abstraction (models and/or decomposition) for structuring and facilitate access to salient information in the sensory data. This layer of abstraction connects high level concepts to low-level sensory pattern.” Relying on modeling and decomposition of sensory data, we present our work on abstract representation for two modalities (laser scanner and camera) in three appended papers. Feasibility and the performance of the proposed methods are evaluated over data from real warehouse. The thesis conclude with summarizing the presented technical details, and drawing the outline for future work.

  • 63.
    Gholami Shahbandi, Saeed
    et al.
    University of Angers, Angers, France.
    Lucidarme, Philippe
    University of Angers, Angers, France.
    Object Recognition Based on Radial Basis Function Neural Networks: experiments with RGB-D camera embedded on mobile robots2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    An object recognition strategy based on artificial radial basis functions neural networks is presented in this paper. The general context of this work is to recognize object from captures made by a mobile robot. Unlike classical approaches which always select the closest object, our method outputs a set of potential candidates if the input information is not enough discriminant. There are three main steps in our approach: objects segmentation, signature extraction and classification. Segmentation is inspired from previous works and is shortly described. Signature extraction based on global geometric and color features is detailed. Classification based on artificial neural networks is also explained and architecture of the network is justified. Finally a real experiment made with a RGB-D camera mounted on a mobile robot is presented and classification results is criticized.

  • 64.
    Gholami Shahbandi, Saeed
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Magnusson, Martin
    Örebro University, Örebro, Sweden.
    2D Map Alignment With Region Decomposition2019Ingår i: Autonomous Robots, ISSN 0929-5593, E-ISSN 1573-7527, Vol. 43, nr 5, s. 1117-1136Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In many applications of autonomous mobile robots the following problem is encountered. Two maps of the same environment are available, one a prior map and the other a sensor map built by the robot. To benefit from all available information in both maps, the robot must find the correct alignment between the two maps. There exist many approaches to address this challenge, however, most of the previous methods rely on assumptions such as similar modalities of the maps, same scale, or existence of an initial guess for the alignment. In this work we propose a decomposition-based method for 2D spatial map alignment which does not rely on those assumptions. Our proposed method is validated and compared with other approaches, including generic data association approaches and map alignment algorithms. Real world examples of four different environments with thirty six sensor maps and four layout maps are used for this analysis. The maps, along with an implementation of the method, are made publicly available online. © 2018, The Author(s).

  • 65.
    Gholami Shahbandi, Saeed
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Magnusson, Martin
    Örebro University, Örebro, Sweden .
    Iagnemma, Karl
    Massachusetts Institute of Technology, Cambridge, MA, USA.
    Nonlinear Optimization of Multimodal Two-Dimensional Map Alignment With Application to Prior Knowledge Transfer2018Ingår i: IEEE Robotics and Automation Letters, ISSN 2377-3766, E-ISSN 1949-3045, Vol. 3, nr 3, s. 2040-2047Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose a method based on a nonlinear transformation for nonrigid alignment of maps of different modalities, exemplified with matching partial and deformed two-dimensional maps to layout maps. For two types of indoor environments, over a dataset of 40 maps, we have compared the method to state-of-the-art map matching and nonrigid image registration methods and demonstrate a success rate of 80.41% and a mean point-to-point alignment error of 1.78 m, compared to 31.9% and 10.7 m for the best alternative method. We also propose a fitness measure that can quite reliably detect bad alignments. Finally, we show a use case of transferring prior knowledge (labels/segmentation), demonstrating that map segmentation is more consistent when transferred from an aligned layout map than when operating directly on partial maps (95.97% vs. 81.56%). © 2018 IEEE.

  • 66.
    Gholami Shahbandi, Saeed
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Åstrand, Björn
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Philippsen, Roland
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Semi-Supervised Semantic Labeling of Adaptive Cell Decomposition Maps in Well-Structured Environments2015Ingår i: 2015 European Conference on Mobile Robots (ECMR), Piscataway, NJ: IEEE Press, 2015, artikel-id 7324207Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present a semi-supervised approach for semantic mapping, by introducing human knowledge after unsupervised place categorization has been combined with an adaptive cell decomposition of an occupancy map. Place categorization is based on clustering features extracted from raycasting in the occupancy map. The cell decomposition is provided by work we published previously, which is effective for the maps that could be abstracted by straight lines. Compared to related methods, our approach obviates the need for a low-level link between human knowledge and the perception and mapping sub-system, or the onerous preparation of training data for supervised learning. Application scenarios include intelligent warehouse robots which need a heightened awareness in order to operate with a higher degree of autonomy and flexibility, and integrate more fully with inventory management systems. The approach is shown to be robust and flexible with respect to different types of environments and sensor setups. © 2015 IEEE

  • 67.
    Gholami Shahbandi, Saeed
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Åstrand, Björn
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Philippsen, Roland
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Sensor Based Adaptive Metric-Topological Cell Decomposition Method for Semantic Annotation of Structured Environments2014Ingår i: 2014 13th International Conference on Control Automation Robotics & Vision (ICARCV), Piscataway, NJ: IEEE Press, 2014, s. 1771-1777, artikel-id 7064584Konferensbidrag (Refereegranskat)
    Abstract [en]

    A fundamental ingredient for semantic labeling is a reliable method for determining and representing the relevant spatial features of an environment. We address this challenge for planar metric-topological maps based on occupancy grids. Our method detects arbitrary dominant orientations in the presence of significant clutter, fits corresponding line features with tunable resolution, and extracts topological information by polygonal cell decomposition. Real-world case studies taken from the target application domain (autonomous forklift trucks in warehouses) demonstrate the performance and robustness of our method, while results from a preliminary algorithm to extract corridors, and junctions, demonstrate its expressiveness. Contribution of this work starts with the formulation of metric-topological surveying of environment, and a generic n-direction planar representation accompanied with a general method for extracting it from occupancy map. The implementation also includes some semantic labels specific to warehouse like environments. © 2014 IEEE.

  • 68.
    Gonzalez, Ramon
    et al.
    Massachusetts Institute of Technology, Cambridge, MA, USA.
    Byttner, Stefan
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab).
    Iagnemma, Karl
    Massachusetts Institute of Technology, Cambridge, MA, USA.
    Comparison of Machine Learning Approaches for Soil Embedding Detection of Planetary Exploration Rovers2016Ingår i: Proceedings of the 8th ISTVS Americas Conference, Detroit, September 12-14, 2016., 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper analyzes the advantages and limitations of known machine learning approaches to cope with the problem of incipient rover embedding detection based on propioceptive signals. In particular, two supervised learning approaches (Support Vector Machines and Feed-forward Neural Networks) are compared to two unsupervised learning approaches (K-means and Self-Organizing Maps) in order to identify various degrees of slip (e.g. low slip, moderate slip, high slip). A real dataset collected by a single-wheel testbed available at MIT has been used to validate each strategy. The SVM algorithm achieves the best performance (accuracy >95 %). However, the SOM algorithm represents a better solution in terms of accuracy and the need of hand-labeled data for training the classifier (accuracy >84 %).

  • 69.
    Grünwald, Norbert
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligenta system (IS-lab).
    A Mixed-Reality Platform for Robotics and Intelligent Vehicles2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Mixed Reality is the combination of the real world with a virtual one. In robotics thisopens many opportunities to improve the existing ways of development and testing. Thetools that Mixed Reality gives us, can speed up the development process and increasesafety during the testing stages. They can make prototyping faster and cheaper, and canboost the development and debugging process thanks to visualization and new opportunitiesfor automated testing.In this thesis the steps to build a working prototype demonstrator of a Mixed Realitysystem are covered. From selecting the required components, over integrating them intofunctional subsystems, to building a fully working demonstration system.The demonstrator uses optical tracking to gather information about the real world environment.It incorporates this data into a virtual representation of the world. This allowsthe simulation to let virtual and physical objects interact with each other. The results ofthe simulation are then visualized back into the real world.The presented system has been implemented and successfully tested at the HalmstadUniversity.

  • 70.
    Gustavsson, Martin
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Frimodig, Viktor
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Virtual Prototyping and Physical Validation of an Inverted Pendulum: "Sea-Calf Bot"2015Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Arbetet motiveras av målet att knyta samman verklighet och modell, samt att se om det finns möjlighet att utveckla ett billigt utbildningsverktyg för utbildning i cyberfysiska system.

    Detta projekt har undersökt möjligheter att bygga en billig inverterad pendel med regulator samt koppla samman denna med modelleringsspråket Acumen. I Acumen skapa en modell av systemet och jämföra den med en fysisk prototyp.

    För att lösa dessa problem har en 3D skrivare använts för att skapa hårdvara. Arduino UNO för styrning och Raspberry Pi för att möjligöra kommunikation med Acumen över WLAN.

    Resultatet blev en billig inverterad pendel, som kan byggas för en kostnad runt 750 kr. Grafer från Acumen, och från data samlad från sensorer kan analyseras.

    Med en modell av en inverterad pendel visar resultaten att Acumen kan användas i utveckling av cyberfysiska system. Skillnader finns mellan modell och verklighet men även likheter.

  • 71.
    Gülseven, Metin
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Davidsson, Viktor
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Dead reckoning using trigonometry in a dual robot system2017Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In this thesis fundamental pieces of multi robot systems have been discussed and researched, in order to develop and build a system with easily obtainable electronics and to answer how much communication is needed as well as which design choices are important to make it robust. Our work will hopefully contribute to others in the community who are working with Raspberry Pi and Windows 10 IoT Core by being open source. As a result a proof of concept system of two simple robots has been implemented.

    In this paper we have used trigonometry and dead-reckoning for localization, when coordinating our robots a leader/follower model has been applied. The communication has been developed using the AllJoyn framework to develop an interface that has IoT capabilities.

    The results show that our system has working communication and simulated localization, however the limitations in the hardware results in an error in localization which we present in this paper. To answer our research questions the amount of communication needed is dependent on the problem and how many robots you need to apply in order to solve it and the most important design choice for current multi robot systems is a controlled environment.

  • 72.
    Halatci, Ibrahim
    et al.
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, United States.
    Brooks, Christopher A.
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, United States.
    Iagnemma, Karl
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, United States.
    A study of visual and tactile terrain classification and classifier fusion for planetary exploration rovers2008Ingår i: Robotica (Cambridge. Print), ISSN 0263-5747, E-ISSN 1469-8668, Vol. 26, nr 6, s. 767-779Artikel i tidskrift (Refereegranskat)
  • 73.
    Halatci, Ibrahim
    et al.
    Massachusetts Institute of Technology, Department of Mechanical Engineering, 77 Massachusetts Avenue, Cambridge, MA 02139, United States.
    Brooks, Christopher A.
    Massachusetts Institute of Technology, Department of Mechanical Engineering, 77 Massachusetts Avenue, Cambridge, MA 02139, United States.
    Iagnemma, Karl
    Massachusetts Institute of Technology, Department of Mechanical Engineering, 77 Massachusetts Avenue, Cambridge, MA 02139, United States.
    Terrain Classification and Classifier Fusion for Planetary Exploration Rovers2007Ingår i: Aerospace Conference, 2007 IEEE, Piscataway: IEEE Press, 2007, s. 1-11Konferensbidrag (Refereegranskat)
    Abstract [en]

    Knowledge of the physical properties of terrain surrounding a planetary exploration rover can be used to allow a rover system to fully exploit its mobility capabilities. Here a study of multi-sensor terrain classification for planetary rovers in Mars and Mars-like environments is presented. Two classification algorithms for color, texture, and range features are presented based on maximum likelihood estimation and support vector machines. In addition, a classification method based on vibration features derived from rover wheel-terrain interaction is briefly described. Two techniques for merging the results of these "low-level" classifiers are presented that rely on Bayesian fusion and meta-classifier fusion. The performance of these algorithms is studied using images from NASA's Mars Exploration Rover mission and through experiments on a four-wheeled test-bed rover operating in Mars-analog terrain. It is shown that accurate terrain classification can be achieved via classifier fusion from visual and tactile features.

  • 74.
    Hasan, Meqdad
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligenta system (IS-lab).
    Kali, Rahul
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligenta system (IS-lab).
    Method for Autonomous picking of paper reels2011Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Autonomous forklift handling systems is one of the most interesting research in the last decades. While research fields such as path planning and map building are taking the most significant work for other type of autonomous vehicles, detecting objects that need to move and picking it up becomes one of the most important research fields in autonomous forklifts field.

    We in this research had provided an algorithm for detecting paper reels accurate position in paper reels warehouses giving a map of the warehouse itself. Another algorithm is provided for giving the priority of papers that want to be picked up. Finally two algorithms for choosing the most appropriate direction for picking the target reel and for choosing the safest path to reach the target reel without damage it are provided.

    While working on the last two algorithms shows very nice results, building map for unknown stake of papers by accumulating maps over time still tricky. In the following pages we will go in detail by the steps that we followed to provide these algorithms started from giving an over view to the problem background and moving through the method that we used or we developed and ending by result and the conclusion that we got from this work.

  • 75.
    Helmick, D.
    et al.
    Jet Propulsion Laboratory.
    Angelova, A.
    Jet Propulsion Laboratory.
    Matthies, L.
    Jet Propulsion Laboratory.
    Brooks, C.
    MIT.
    Halatci, I.
    MIT.
    Dubowsky, S.
    MIT.
    Iagnemma, Karl
    MIT.
    Experimental Results from a Terrain Adaptive Navigation System for Planetary Rovers2008Ingår i: Proceedings of the Ninth International Symposium on Artificial Intelligence, Robotics and Automation in Space, i-SAIRAS, 2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    Results from the experimental testing of a navigation system for planetary rovers called Terrain Adaptive Navigation (TANav) are shown here. This system was designed to enable greater access to and more robustoperations in terrains with widely varying slippage.The system achieves this goal by using onboard stereocameras to remotely classify terrain, predict the slippage of that terrain, and use this information in the planning of a path to the goal. An end-to-end onboard demonstration of the system in a Mars analog environment is shown with promising results.

  • 76.
    Henriksson, Kim
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Hellström, Patrik
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Vidareutveckling av granulat 3d-skrivare2017Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The average 3d-printer has a relatively small print surface which limits the sizeof the prints themselves and there is a void on the market for printers that can printparts as big as, for instance, a car bumper . This project aims to further advancethe construction of a large 3d-printer started by previous students at Halmstad University and focuses at print quality and accuracy.

  • 77.
    Hotze, Wolfgang
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Robotic First Aid: Using a mobile robot to localise and visualise points of interest for first aid2016Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Domestic robots developed to support human beings by performing daily tasks such as cleaning should also be able to help in emergencies by finding, analysing, and assisting persons in need of first aid. Here such a robot capable of performing some useful task related to first aid is referred to as a First Aid Mobile Robot (FAMR). One challenge which to the author's knowledge has not been solved is how such a FAMR can find a fallen person's pose within an environment, recognising locations of points of interest for first aid such as the mouth, nose, chin, chest and hands on a map. To overcome the challenge, a new approach is introduced based on leveraging a robot's capabilities (multiple sensors and mobility), called AHBL. AHBL comprises four steps: Anomaly detection, Human detection, Body part recognition, and Localisation on a map. It was broken down into four steps for modularity (e.g., a different way of detecting anomalies can be slipped in without changing the other modules) and because it was not clear which step is hardest to implement. As a result of evaluating AHBL, a FAMR developed for this work was able to find the pose of a fallen person (a mannequin) in a known environment with an average success rate of 83%, and an average localisation discrepancy of 1.47cm between estimated body part locations and ground truth. The presented approach can be adapted for use in other robots and contexts, and can act as a starting point toward designing systems for autonomous robotic first aid.

  • 78.
    Howard, A.
    et al.
    Space Exploration Technologies Corporation (SpaceX), CA, Unites States.
    Iagnemma, Karl
    Massachusetts Institute of Technology, Cambridge, Massachusetts, United States.
    Kelly, A.
    Carnegie Mellon University, Unites States.
    Seventh International Conference on Field and Service Robotics2010Ingår i: The international journal of robotics research, ISSN 0278-3649, E-ISSN 1741-3176, Vol. 29, nr 12, s. 1459-1460Artikel i tidskrift (Refereegranskat)
  • 79.
    Iagnemma, Karl
    Massachusetts Institute of Technology, Cambridge, Massachusetts, United States.
    Terrain Estimation Methods for Enhanced Autonomous Rover Mobility2006Ingår i: Intelligence for Space Robotics / [ed] Ayanna M. Howard & Edward W. Tunstel, San Antonio, Tex.: TSI Press , 2006Kapitel i bok, del av antologi (Refereegranskat)
  • 80.
    Iagnemma, Karl
    et al.
    Boston Dynamics, Boston, MA, United States.
    Buehler, M.
    Boston Dynamics, Boston, MA, United States.
    Editorial for Journal of Field Robotics: Special issue on the DARPA Grand Challenge2006Ingår i: Journal of Field Robotics, ISSN 1556-4959, Vol. 23, nr 9, s. 655-656Artikel i tidskrift (Refereegranskat)
  • 81.
    Iagnemma, Karl
    et al.
    Massachusetts Institute of Technology, Cambridge, Massachusetts, United States.
    Martinet, Philippe
    Blaise Pascal University, Clermont-Ferrand, France.
    Wang, Danwei
    Nanyang Technological University, Singapore.
    Introduction: Vehicle–Terrain Interaction for Mobile Robots2010Ingår i: Journal of Field Robotics, ISSN 1556-4959, Vol. 27, nr 2, s. 105-106Artikel i tidskrift (Refereegranskat)
  • 82.
    Iagnemma, Karl
    et al.
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.
    Peters, Steven
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.
    Stability Measurement of High Speed Vehicles on Sloped and Rough Terrain2009Ingår i: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 47, nr 6, s. 701-720Artikel i tidskrift (Refereegranskat)
  • 83.
    Iagnemma, Karl
    et al.
    MIT.
    Senatore, C.
    MIT.
    Trease, B.
    Caltech.
    Arvidson, R.
    MIT.
    Bennett, K.
    MIT.
    Shaw, A.
    MIT.
    Zhou, F.
    MIT.
    Van Dyke, L.
    MIT.
    Lindemann, R.
    Caltech.
    Terramechanics Modeling of Mars Surface Exploration Rovers for Simulation and Parameter Estimation2011Ingår i: Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference--2011: : presented at ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, August 28-31, 2011, Washington, D.C., New York: ASME Press, 2011, s. 805-812Konferensbidrag (Refereegranskat)
    Abstract [en]

    In 1997 and 2004, small wheeled robots ("rovers") landed on the surface of Mars to conduct scientific experiments focused on understanding the planet's climate history, surface geology, and potential for past or present life. Recently, the Mars Exploration Rover(MER)"Spirit"became deeply embedded in regolith at a site called Troy, ending its mission as a mobile science platform. The difficultyfaced in navigating mobile robots over sloped, rocky, and deformable terrain has highlighted the importance of developing accurate simulation tools for use in a predictive mobility modeling capacity. These simulation tools require accurate knowledge of terrain model parameters.This paperdescribes a terramechanics-based toolfor simulation of rover mobility. It also describes ongoing work toward estimation of terrain parameters of Mars soil. Copyright © 2011 by ASME.

  • 84.
    Iagnemma, Karl
    et al.
    Massachusetts Institute of Technology, Cambridge, MA, United States.
    Shibly, Hassan
    Birzeit University, Birzeit, Palestinian Territories.
    Dubowsky, Steven
    Massachusetts Institute of Technology, Cambridge, MA, United States.
    On-Line Terrain Parameter Estimation for Planetary Rovers2002Ingår i: Proceedings: 2002 IEEE International Conference on Robotics and Automation, May 11–15, Washington D.C., Piscataway, NJ: IEEE Press, 2002, Vol. 3, s. 3142-3147Konferensbidrag (Refereegranskat)
    Abstract [en]

    Future planetary exploration missions will require rovers to traverse very rough terrain with limited human supervision. Wheel-terrain interaction plays a critical role in rough-terrain mobility. In this paper an on-line estimation method that identifies key terrain parameters using on-board rover sensors is presented. These parameters can be used for accurate traversability prediction or in a traction control algorithm. These parameters are also valuable indicators of planetary surface soil composition. Simulation and experimental results show that the terrain estimation algorithm can accurately and efficiently identify key terrain parameters for loose sand.

  • 85.
    Iagnemma, Karl
    et al.
    MIT.
    Shimoda, Shingo
    RIKEN BSI, Japan.
    Shiller, Zvi
    Ariel University Center, Israel.
    Near-Optimal Navigation of High Speed Mobile Robots on Uneven Terrain2008Ingår i: 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS, Vols 1-3, Piscataway, N.J.: IEEE Press, 2008, s. 4098-4103Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper proposes a method for near-optimal navigation of high speed mobile robots on uneven terrain. The method relies on a layered control strategy. A high-level planning layer generates an optimal desired trajectory through uneven terrain. A low-level navigation layer guides a robot along the desired trajectory via a potential field-based control algorithm. The high-level planner is guaranteed to yield optimal trajectories but is computationally intensive. The low-level navigation layer is sub-optimal but computationally efficient. To guard against failures at the navigation layer, a model-based lookahead approach is employed that utilizes a reduced form of the optimal trajectory generation algorithm. Simulation results show that the proposed method can successfully navigate a mobile robot over uneven terrain while avoiding hazards. A comparison of the method's performance to a similar algorithm is also presented. ©2008 IEEE.

  • 86.
    Iagnemma, Karl
    et al.
    MIT.
    Udengaard, M.
    MIT.
    Ishigami, G.
    MIT.
    Spenko, M.
    Illinois Institute of Technology.
    Oncu, S.
    Illinois Institute of Technology.
    Khan, I.
    Illinois Institute of Technology.
    Overholt, J.
    U.S. Army Tank Automotive Research Development and Engineering Center (TARDEC).
    Hudas, G.
    U.S. Army Tank Automotive Research Development and Engineering Center (TARDEC).
    Design and Development of an Agile, Man Portable Unmanned Ground Vehicle2008Ingår i: Proceedings of the 26th Annual Army Science Conference, 2008, s. 1-8Konferensbidrag (Refereegranskat)
    Abstract [en]

    An omnidirectional unmanned ground vehicle (UGV)is able to move in any planar direction regardless of itscurrent pose. To date, nearly all designs and analyses ofomnidirectional robots have considered the case ofmotion on flat, smooth terrain. This paper presents thedesign, analysis, and prototype development of a manportable omnidirectional UGV designed for operation inrough terrain. Design guidelines are presented that arederived from geometric constraints on wheel and linkagesizes. The effects of terrain roughness and loss of wheelcontact on UGV mobility are also analyzed.Aframework for UGV design optimization is presented thatconsiders vehicle kinematic isotropy, wheel-terraininteraction properties, predicted obstacle traversability,and maximum traversable distance over various outdoorterrain types. The results are used to design two small(i.e. 1m characteristic length), lightweight (i.e.approximately 25 kg) UGV prototypes.

  • 87.
    Iagnemma, Karl
    et al.
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, USA.
    Ward, Chris C.
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, USA.
    Classification-based wheel slip detection and detector fusion for mobile robots on outdoor terrain2009Ingår i: Autonomous Robots, ISSN 0929-5593, E-ISSN 1573-7527, Vol. 26, nr 1, s. 33-46Artikel i tidskrift (Refereegranskat)
  • 88.
    Ishigami, G.
    et al.
    Japan Aerospace Exploration Agency, Sagamihara, Japan.
    Otsuki, M.
    Japan Aerospace Exploration Agency, Sagamihara, Japan.
    Kubota, T.
    Japan Aerospace Exploration Agency, Sagamihara, Japan.
    Iagnemma, Karl
    MIT.
    Modeling of Flexible and Rigid Wheels for Exploration Rover on Rough Terrain2011Ingår i: Proceedings of the 28th International Symposium on Space Technology and Science, 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a comprehensive wheel model that can quantitatively evaluate traction performance of flexible/rigid wheelsdriving on deformable terrain. The proposed model exploits a terramechanics-based approach with taking account of pressures generated by wheel elasticity as well as terrain stiffness. Deflection of a flexible wheel typically depends on a relative pressure between thewheel and terrain: the wheel will be significantly deformed on rigid terrain whereas it will be hardly deformed on soft terrain. Therefore, the wheel-terrain interaction in the proposed model is divided into three contact sections: wheel front section, wheel deflected(flat) section, and wheel rear section. The traction force of the wheel is obtained as an integral of normal and shear stresses generatedat each section. Simulation studies with varied wheel pressures, such as flexible, semi-flexible, and rigid wheels, are conducted tovalidate the proposed model. Also, traction performances of flexible/rigid wheels are compared based on a metric called tractiveefficiency. The comparison implies an optimal wheel pressure of flexible wheel for better traction performance.

  • 89.
    Ishigami, G.
    et al.
    Japan Aerospace Exploration Agency.
    Overholt, J.
    TARDEC.
    Iagnemma, Karl
    MIT.
    Multi-material Anisotropic Friction Wheels for Omnidirectional Ground Vehicles2010Ingår i: Proceedings of the ICAM 5th International Conference on Advanced Mechatronics, 2010, s. 658-662Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, a novel omnidirectional vehicle with anisotropic friction wheels is presented. The proposed wheel has a series of bendable “nodes” on its circumference, each of which is made of two materials with differing friction properties: one material exhibits high friction, and the other exhibits low friction. The high friction section of the node generates a high traction force, while the low friction section enables the wheel to passively slide. The wheels are arranged such that the robot wheel exhibits high traction in its driving direction (much like a conventional tire), but low traction when sliding laterally. Due to this “anisotropic friction” property, the proposed wheel enables a vehicle to realize omnidirectional motion (i.e. the vehicle can move any direction within the plane—forward, back, or laterally). While many other omnidirectional wheel drives exist, the proposed wheel is simpler than any other existing design because the wheel is composed of a single, moldable element. This paper summarizes the design of the proposed wheel and presents a comparison between a small omnidirectional vehicle that uses the proposed wheel and an omnidirectional vehicle that uses conventional wheels.

  • 90.
    Ishigami, G.
    et al.
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, 252-5210, Japan.
    Pineda, E.
    MIT.
    Overholt, J.
    U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC), Warren, MI 48397, United States.
    Hudas, G.
    U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC), Warren, MI 48397, United States.
    Iagnemma, Karl
    MIT.
    Performance analysis and odometry improvement of an omnidirectional mobile robot for outdoor terrain2011Ingår i: Proceedings: 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems : September 25-30, 2011, San Francisco, California, USA, Piscataway, N.J.: IEEE Press, 2011, s. 4091-4096Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper an omnidirectional mobile robot that possesses high mobility in rough terrain is presented. The omnidirectional robot has four active split offset caster (ASOC) modules, enabling the robot to move in any planar direction. It also possesses passive suspension articulation, allowing the robot to conform to uneven terrain. The agility of the robot is experimentally evaluated in various configurations. In addition, an odometry method that mitigates position estimation error due to wheel slippage is proposed. A key aspect of the proposed method is to utilize sensory data of wheel velocity, and turning rate around each ASOC pivot shaft, along with kinematic constraints of the robot configuration. Experimental odometry tests with different maneuvers in rough terrain are presented that confirm the utility of the proposed method. © 2011 IEEE.

  • 91.
    Ishigami, Genya
    et al.
    Massachusetts Institute of Technology, Cambridge, Massachusetts, United States.
    Kewlani, Gaurav
    Massachusetts Institute of Technology, Cambridge, Massachusetts, United States.
    Iagnemma, Karl
    Massachusetts Institute of Technology, Cambridge, Massachusetts, United States.
    Predictable Mobility: A Statistical Approach for Planetary Surface Exploration Rovers in Uncertain Terrain2009Ingår i: IEEE robotics & automation magazine, ISSN 1070-9932, E-ISSN 1558-223X, Vol. 16, nr 4, s. 61-70Artikel i tidskrift (Refereegranskat)
  • 92.
    Ishigami, Genya
    et al.
    MIT, USA.
    Kewlani, Gaurav
    MIT, USA.
    Iagnemma, Karl
    MIT, USA.
    Statistical Approach to Mobility Prediction for Planetary Surface Exploration Rovers in Uncertain Terrain2009Ingår i: IEEE robotics & automation magazine, ISSN 1070-9932, E-ISSN 1558-223X, Vol. 16, nr 4, s. 61-70Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Planetary surface exploration rovers must accurately and efficiently predict their mobility on natural, rough terrain. Most approaches to mobility prediction assume precise a priori knowledge of terrain physical parameters, however in practical scenarios knowledge of terrain parameters contains significant uncertainty. In this paper, a statistical method for mobility prediction that incorporates terrain uncertainty is presented. The proposed method consists of two techniques: a wheeled vehicle model for calculating vehicle dynamic motion and wheel-terrain interaction forces, and a stochastic response surface method (SRSM) for modeling of uncertainty. The proposed method generates a predicted motion path of the rover with confidence ellipses indicating the probable rover position due to uncertainty in terrain physical parameters. Rover orientations and wheel slippage are also predicted. The computational efficiency of SRSM as compared to conventional Monte Carlo methods is shown via numerical simulations. Experimental results of rover travel over sloped terrain in two different uncertain terrains are presented that confirms the utility of the proposed mobility prediction method. ©2010 IEEE.

  • 93.
    Ishigami, Genya
    et al.
    MIT, USA.
    Kewlani, Gaurav
    MIT, USA.
    Iagnemma, Karl
    MIT, USA.
    Statistical Mobility Prediction for Planetary Surface Exploration Rovers in Uncertain Terrain2010Ingår i: 2010 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), Piscataway, N.J.: IEEE Press, 2010, s. 588-593Konferensbidrag (Refereegranskat)
    Abstract [en]

    Planetary surface exploration rovers must accurately and efficiently predict their mobility on natural, rough terrain. Most approaches to mobility prediction assume precise a priori knowledge of terrain physical parameters, however in practical scenarios knowledge of terrain parameters contains significant uncertainty. In this paper, a statistical method for mobility prediction that incorporates terrain uncertainty is presented. The proposed method consists of two techniques: a wheeled vehicle model for calculating vehicle dynamic motion and wheel-terrain interaction forces, and a stochastic response surface method (SRSM) for modeling of uncertainty. The proposed method generates a predicted motion path of the rover with confidence ellipses indicating the probable rover position due to uncertainty in terrain physical parameters. Rover orientations and wheel slippage are also predicted. The computational efficiency of SRSM as compared to conventional Monte Carlo methods is shown via numerical simulations. Experimental results of rover travel over sloped terrain in two different uncertain terrains are presented that confirms the utility of the proposed mobility prediction method. ©2010 IEEE.

  • 94.
    Ishigami, Genya
    et al.
    Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 252-5210, Japan.
    Overholt, Jim
    United States Army TARDEC, 6501 E. 11 Mile Road, Warren, MI 48397, USA.
    Iagnemma, Karl
    Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA.
    Multi-material Anisotropic Friction Wheels for Omnidirectional Ground Vehicles2012Ingår i: Journal of Robotics and Mechatronics, ISSN 0915-3942, Vol. 24, nr 1, s. 261-267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, a novel wheel design utilizing the anisotropic friction property for omnidirectional vehicles is presented. The proposedwheel has a series of bendable "nodes" on its circumference, each of which is made of two materials with differing friction properties: onematerial exhibits high friction, and the other exhibits low friction. The high friction section of the node generates a high traction force, while the low friction section enables the wheel to passively skid. The wheels are arranged such that the robot wheel exhibits high traction in its drive direction (much like a conventional tire), but low traction when sliding laterally. Exploiting this "anisotropic friction" property, the proposed wheel enables a vehicle to realize omnidirectional motion (i.e., the vehicle can move any direction within the plane - forward, back, or laterally). While many other omnidirectional wheel drives exist, the proposed wheel is simpler than any other existing design because the wheel is composed of a single, moldable element. This paper summarizes the design of the proposed wheel and presents experimental comparisons between an omnidirectional robot using the proposed wheel and an omnidirectional robot using conventionalwheels.

  • 95.
    Joachimbauer, Florian
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Concise Modeling of Humanoid Dynamics2017Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Simulation of mechanical systems like walking robots, is an essential part in developingnew and more applicable solutions in robotics. The increasing complexity of methodsand technologies is a key challenge for common languages. That problem creates a needfor flexible and scalable languages. The thesis concludes that an equation-based toolusing the Euler-Lagrange can simplify the process cycle of modeling and simulation. Itcan minimize the development effort, if the tool supports derivatives. Regretfully, it isnot common to use equation-based tools with this ability for simulation of humanoidrobots.The research in this thesis illustrates the comparison of equation-based tools to commonused tools. The implementation uses the Euler-Lagrange method to model andsimulate nonlinear mechanical systems. The focus of this work is the comparison ofdifferent tools, respectively the development of a humanoid robot in a stepwise mannerbased on the principle of passive walking. Additionally, each developed model has givenan informal argument to its stability. To prove the correctness of the thesis statementthe equation-based tool called Acumen is evaluated in contrast to a common used tool,MATLAB.Based on the achieved results, it can be concluded that the use of equation-based toolsusing Euler-Lagrange formalism is convenient and scalable for humanoid robots. Additionally,the development process is significantly simplified by the advantages of suchtools. Due to the experimental nature of Acumen further research could investigatethe possibilities for different mechanical systems as well as other techniques.

  • 96.
    Johansson, Fredrik
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Dahl, Oskar
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Autonomous Validation through Visual Inspection2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The industrial testing phase of graphical user interfaces and the behaviour of screens, is still involving manual tests with human interaction. This type of testing is particularly difficult and time consuming to manually perform, due to time sensitive messages and information used within these interfaces. This thesis address this issue by introducing an approach to automate this process by utilizing high grade machine vision cameras and existing algorithm implementations from OpenCV 3.2.0. By knowing the expected graphical representation in advance, a comparison between the actual outcome and this expectation can be evaluated by applying image processing algorithms. It is found that this approach presents an Equal Error Rate of 6% while still maintaining a satisfactory time performance, in relation to the timeframe requirement of these time sensitive messages. Accuracy and time performance is profoundly affected by hardware equipment, partially due to the immense amount of image processing involved.

  • 97.
    Jouda, Fatma
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS).
    Mehdi, Sagar
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS).
    Safety Verification in Vehicle Test Applications: Using Reachability Analysis With the Focus on Reachability Tools2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 98.
    Karlsson, Patrick
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Johansson, Emil
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Object Identifier System for Autonomous UAV: A subsystem providing methods for detecting and descending to an object. The object is located in a specified area with a coverage algorithm.2018Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Användandet av UAVs i det vardagliga livet har ökat markant de senaste åren. En UAV är ett agilt fordon som ofta kommer integrerat med en kamera samt sensorer som gör det till ett lämpligt fordon för objektigenkänning och spårning. I den här avhandligen presenterar vi ett delsystem med en hårdvaruplattform endast bestående av en inbyggd dator och en kamera. Delsystemet tillhandahåller metoder som gör det möjligt för UAV:en att styras, känna igen objekt och landa på det detekterade objektet autonomt. Systemet implementeras i Robotic Operating System (ROS). Objektigenkänningen är implementerat som ett konvolutionellt neuralt nätverk tillhandahållt av TensorFlow Object Detection API. Avhandlingen omfattar stegen nödvändiga att ta för att anpassa en TensorFlow model till sina egna behov och gör jämförelser mellan tre olika Tensorflow modeller med avseende på precision, bildrutor per sekund och energi effektivitet. Dessutom presenteras metoder för att söka av ett fördefinierat område och positionering av ett objekt relativt komeran. Under experiment, både i simulering och verkliga världen, har lovande resultat framkommit.

  • 99.
    Karumanchi, Sisir
    et al.
    MIT.
    Iagnemma, Karl
    MIT.
    Reactive control in environments with hard and soft hazards2012Ingår i: Intelligent Robots and Systems (IROS), 2012 IEEE/RSJ International Conference on, Piscataway, N.J.: IEEE Press, 2012, s. 2863-2868Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we present a generalization of reactive obstacle avoidance algorithms for mobile robots operating among soft hazards such as off-road slopes and deformable terrain. A new hazard avoidance scheme generalizes constraint based reactive algorithms [1], [2] from hard to soft hazards. Reactive controllers operate by directly parameterizing the closedloop dynamics of the system with respect to the environment the robot is operating in. Traditionally, reactive controllers are parameterized by weighting virtual attraction and repulsion forces from goals and obstacles [3], [4]. One pitfall of such parameterizations is sensitivity of the tuning parameters to the operating environment. A reactive controller tuned in one set of conditions is not applicable in another (e.g. a different density of obstacles). The algorithm presented in this paper has two key properties which are significant i) Parameterization is environment independent. ii) It can deal with non-binary environments that contain soft hazards. © 2012 IEEE.

  • 100.
    Kewlani, Gaurav
    et al.
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
    Crawford, Justin
    Quantum Signal LLC, Ann Arbor, MI, USA.
    Iagnemma, Karl
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
    A polynomial chaos approach to the analysis of vehicle dynamics under uncertainty2012Ingår i: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 50, nr 5, s. 749-774Artikel i tidskrift (Refereegranskat)
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